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Sample records for anatomical variation effect

  1. Complex anatomic variation in the brachial region.

    Science.gov (United States)

    Troupis, Th; Michalinos, A; Protogerou, V; Mazarakis, A; Skandalakis, P

    2015-01-01

    Authors describe a case of a complex anatomic variation discovered during dissection of the humeral region. On the right side, brachial artery followed a superficial course. Musculocutaneous nerve did not pierce coracobrachialis muscle but instead passed below the muscle before continuing in the forearm. On the left side, a communication between musculocutaneous and median nerve was dissected. Those variations are analytically presented with a brief review on their anatomic and clinical implications. Considerations on their embryological origin are attempted.

  2. The effects of anatomic resolution, respiratory variations and dose calculation methods on lung dosimetry

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    Babcock, Kerry Kent Ronald

    2009-04-01

    The goal of this thesis was to explore the effects of dose resolution, respiratory variation and dose calculation method on dose accuracy. To achieve this, two models of lung were created. The first model, called TISSUE, approximated the connective alveolar tissues of the lung. The second model, called BRANCH, approximated the lungs bronchial, arterial and venous branching networks. Both models were varied to represent the full inhalation, full exhalation and midbreath phases of the respiration cycle. To explore the effects of dose resolution and respiratory variation on dose accuracy, each model was converted into a CT dataset and imported into a Monte Carlo simulation. The resulting dose distributions were compared and contrasted against dose distributions from Monte Carlo simulations which included the explicit model geometries. It was concluded that, regardless of respiratory phase, the exclusion of the connective tissue structures in the CT representation did not significantly effect the accuracy of dose calculations. However, the exclusion of the BRANCH structures resulted in dose underestimations as high as 14% local to the branching structures. As lung density decreased, the overall dose accuracy marginally decreased. To explore the effects of dose calculation method on dose accuracy, CT representations of the lung models were imported into the Pinnacle 3 treatment planning system. Dose distributions were calculated using the collapsed cone convolution method and compared to those derived using the Monte Carlo method. For both lung models, it was concluded that the accuracy of the collapsed cone algorithm decreased with decreasing density. At full inhalation lung density, the collapsed cone algorithm underestimated dose by as much as 15%. Also, the accuracy of the CCC method decreased with decreasing field size. Further work is needed to determine the source of the discrepancy.

  3. Mutagenic effects of aerospace on Poa pratensis L.. Pt.1: Observation of leaves anatomical variation

    International Nuclear Information System (INIS)

    The dry seeds of Poa pratensis L. 'Nassau' were carried by 'Shenzhou No.3' spaceship and three mutants were screened based on presentational characters from the treated plants and asexual reproduced them as PM1, PM2 and PM3. Observation and investigation were made on the mutants in anatomical characters of the leaves. The results showed that the leaf surface structure and the ultrastructure of the mesophyllous cells changed. Compared to CK, the stoma density increased, but the stoma size decreased with the proportions of total stoma area of leaf area remained unchanged. The chloroplast concentrated to the middle of the cell with volume increase and the shape more roundness. The chloroplast of the mesophyllous cells in the white part of the green-white leaf of PM3 were dissolving or had dissolved. The number of the starch grain also increased in these mutants. (authors)

  4. Introducing International Journal of Anatomical Variations

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    Tunali S

    2008-06-01

    Full Text Available Welcome to International Journal of Anatomical Variations (IJAV - an annual journal of anatomical variations and clinical anatomy case reports. After having a notable experience for eight years in NEUROANATOMY, we are pleased to introduce you IJAV. We are eventually announcing our new journal after three years of feasibility and background study period. We hope that IJAV will fill in the gap in anatomy journals’ bunch. IJAV is an annual, open access journal having electronic version only. Despite of unavailability of a budget for publishing IJAV, the evaluation of submissions and access to the full text articles is totally free of charge.Our vision for IJAV is to constitute an online compendium for anatomical variations in gross, radiological and surgical anatomy, neuroanatomy and case reports in clinical anatomy. We believe that cases have an important role in clinical anatomy education. In this aspect, we aim to serve as an open source of case reports. We hope that IJAV will be cited in most of the case reports related to clinical anatomy and anatomical variations in near future.In NEUROANATOMY, we encouraged the submission of case reports in the area of neuroanatomy. Whereas in IJAV, besides neuroanatomy, we will consider case reports in any area related to human anatomy. The scope of IJAV will encompass any anatomical variations in gross, radiological and surgical anatomy. Case reports in clinical anatomy are also welcome.All submitted articles will be peer-reviewed. No processing fee will be charged from authors. One of the most important features of IJAV will be speedy review and rapid publication. We strive to publish an accepted manuscript within three weeks of initial submission. Our young and dynamic Scientific Advisory Board will achieve this objective.A few remarks about our logo and page design: Prof. Dr. M. Mustafa ALDUR designed our logo, being inspired by a quadricuspid aortic valve case, reported by Francesco FORMICA et al

  5. Quantifying anatomical shape variations in neurological disorders.

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    Singh, Nikhil; Fletcher, P Thomas; Preston, J Samuel; King, Richard D; Marron, J S; Weiner, Michael W; Joshi, Sarang

    2014-04-01

    We develop a multivariate analysis of brain anatomy to identify the relevant shape deformation patterns and quantify the shape changes that explain corresponding variations in clinical neuropsychological measures. We use kernel Partial Least Squares (PLS) and formulate a regression model in the tangent space of the manifold of diffeomorphisms characterized by deformation momenta. The scalar deformation momenta completely encode the diffeomorphic changes in anatomical shape. In this model, the clinical measures are the response variables, while the anatomical variability is treated as the independent variable. To better understand the "shape-clinical response" relationship, we also control for demographic confounders, such as age, gender, and years of education in our regression model. We evaluate the proposed methodology on the Alzheimer's Disease Neuroimaging Initiative (ADNI) database using baseline structural MR imaging data and neuropsychological evaluation test scores. We demonstrate the ability of our model to quantify the anatomical deformations in units of clinical response. Our results also demonstrate that the proposed method is generic and generates reliable shape deformations both in terms of the extracted patterns and the amount of shape changes. We found that while the hippocampus and amygdala emerge as mainly responsible for changes in test scores for global measures of dementia and memory function, they are not a determinant factor for executive function. Another critical finding was the appearance of thalamus and putamen as most important regions that relate to executive function. These resulting anatomical regions were consistent with very high confidence irrespective of the size of the population used in the study. This data-driven global analysis of brain anatomy was able to reach similar conclusions as other studies in Alzheimer's disease based on predefined ROIs, together with the identification of other new patterns of deformation. The

  6. Pterion: An anatomical variation and surgical landmark

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    Prashant E Natekar

    2011-01-01

    Full Text Available Introduction : The frontal and the parietal bones superiorly and the greater wing of the sphenoid and the squamous temporal inferiorly of one side meet at an H-shaped sutural junction termed the pterion. This is an important anatomical and anthropological landmark as it overlies both the anterior branch of middle meningeal artery and the lateral fissure of the cerebral hemisphere. The knowledge of sutural joints between frontal, parietal, sphenoid and temporal bones at pterion is clinically, radiologically and surgically important during surgical interventions involving burr hole surgeries. Materials and Methods : Study performed on 150 dry temporal bones. The pterion, and its sutural articulations with frontal, parietal, sphenoid and temporal bones and also anatomical variations, if any, were studied. Results : Four types of pterion, i.e. sphenoparietal, frontotemporal, stellate and epipteric, were observed. Conclusions : The knowledge of the variations of pterion and its surgical anatomy, in Indian population are important for surgeons operating in the fieldThe present study will also contribute additional information of skull bone fractures in infancy and early childhood, which may be associated with large intersutural bones giving false appearance of fracture radiologically and also during surgical interventions involving burr hole surgeries, as their extensions may lead to continuation of fracture lines.

  7. Anatomical Variations of Cerebral MR Venography: Is Gender Matter?

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    Singh, Rambir; Bansal, Nikhil; Paliwal, Vimal Kumar

    2016-01-01

    Purpose Knowledge of variations in the cerebral dural venous sinus anatomy seen on magnetic resonance (MR) venography is essential to avoid over-diagnosis of cerebral venous sinus thrombosis (CVST). Very limited data is available on gender difference of the cerebral dural venous sinus anatomy variations. Materials and Methods A retrospective study was conducted to study the normal anatomy of the intracranial venous system and its normal variation, as depicted by 3D MR venography, in normal adults and any gender-related differences. Results A total of 1654 patients (582 men, 1072 women, age range 19 to 86 years, mean age: 37.98±13.83 years) were included in the study. Most common indication for MR venography was headache (75.4%). Hypoplastic left transverse sinus was the most common anatomical variation in 352 (21.3%) patients. Left transverse sinus was hypoplastic in more commonly in male in comparison to female (24.9% versus 19.3%, p = 0.009). Most common variation of superior sagittal sinus (SSS) was atresia of anterior one third SSS (15, 0.9%). Except hypoplastic left transverse sinus, rest of anatomical variations of the transverse and other sinuses were not significantly differ among both genders. Conclusion Hypoplastic left transverse sinus is the most common anatomical variation and more common in male compared to female in the present study. Other anatomical variations of dural venous sinuses are not significantly differ among both genders. PMID:27621945

  8. Anatomical variations of paranasal sinuses: what to inform the otolaryngologist?

    International Nuclear Information System (INIS)

    Anatomic variations of paranasal sinuses are common findings in daily practice. For a radiologist, to know these variations is necessary because of the pathological conditions related to them, and also because they are import for planning a functional endoscopic endonasal surgery, the procedure of choice for diagnosis, biopsy and treatment of various sinonasal diseases. To assure that this surgery is done safely, preventing iatrogenic injuries, it is essential that the surgeon has the mapping of these structures. Thus, a CT is indispensable for preoperative evaluation of paranasal sinuses. Since a general radiologist is expected to know these changes and their relationship to pathological conditions, a literature review and a iconographic essay were conducted with the aim of discussing the importance of major anatomic variations of paranasal sinuses. (author)

  9. Anatomic variation and orgasm: Could variations in anatomy explain differences in orgasmic success?

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    Emhardt, E; Siegel, J; Hoffman, L

    2016-07-01

    Though the public consciousness is typically focused on factors such as psychology, penis size, and the presence of the "G-spot," there are other anatomical and neuro-anatomic differences that could play an equal, or more important, role in the frequency and intensity of orgasms. Discovering these variations could direct further medical or procedural management to improve sexual satisfaction. The aim of this study is to review the available literature of anatomical sexual variation and to explain why this variation may predispose some patients toward a particular sexual experience. In this review, we explored the available literature on sexual anatomy and neuro-anatomy. We used PubMed and OVID Medline for search terms, including orgasm, penile size variation, clitoral variation, Grafenberg spot, and benefits of orgasm. First we review the basic anatomy and innervation of the reproductive organs. Then we describe several anatomical variations that likely play a superior role to popular known variation (penis size, presence of g-spot, etc). For males, the delicate play between the parasympathetic and sympathetic nervous systems is vital to achieve orgasm. For females, the autonomic component is more complex. The clitoris is the primary anatomical feature for female orgasm, including its migration toward the anterior vaginal wall. In conclusions, orgasms are complex phenomena involving psychological, physiological, and anatomic variation. While these variations predispose people to certain sexual function, future research should explore how to surgically or medically alter these. Clin. Anat. 29:665-672, 2016. © 2016 Wiley Periodicals, Inc. PMID:26916103

  10. Anatomic variations of anterior cerebral artery cortical branches.

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    Stefani, M A; Schneider, F L; Marrone, A C; Severino, A G; Jackowski, A P; Wallace, M C

    2000-01-01

    The anterior cerebral artery (ACA) is a major vessel responsible for the blood supply to the interhemispheric region. The ACA segment after the anterior communicating artery (AComA) origin is called the distal ACA and has central and cortical branches. The cortical branches are distributed in the different regions of the orbital and medial part of the brain. The objects of this study are the anatomical variations found in the distal ACA. In 76 hemispheres the ACA distal branches were injected with latex and dissected under microscope magnification. Vessel diameters and distances between vessel origins and anterior communicating artery were recorded and analyzed. Microsurgical dissection was carried out to demonstrate anatomic variations of these vessels. Average diameter of ACA at origin was 2.61 +/- 0.34 mm and average diameter of cortical branches diameter ranged from 0.79 +/- 0.27 mm to 1.84 +/- 0.3 mm. Distances between vessel origin and AComA ranged from 7.68 +/- 3.91 mm (orbitofrontal) to 112.6 +/- 11.63 mm (inferior internal parietal). This study found anatomical variations: a single (azygos) ACA was present in one case and three in three cases. Crossing branches of the distal ACA to the contralateral hemisphere were present in 26% of the cases. In some cases a single ACA may supply the posterior hemispheric region through crossing branches. This calls attention to potential bilateral brain infarcts due to a single unilateral ACA occlusion. PMID:10873213

  11. Variations in meniscofemoral ligaments at anatomical study and MR imaging

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    Cho, J.M.; Suh, J.S. [Department of Diagnostic Radiology, Yonsei University College of Medicine, Seoul (Korea, Republic of); Na, J.B. [Department of Diagnostic Radiology, Kyungsang National University, College of Medicine, Jinju (Korea, Republic of); Cho, J.H. [Department of Diagnostic Radiology, Ajou University College of Medicine, Suwon (Korea, Republic of); Kim, Y.; Yoo, W.K. [Department of Rehabilitation, Yonsei University College of Medicine, Seoul (Korea, Republic of); Lee, H.Y.; Chung, I.H. [Department of Anatomy, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1999-04-01

    Purpose To demonstrate variations in the meniscofemoral ligaments (ligaments of Wrisberg and Humphrey) at anatomical study and magnetic resonance (MR) imaging. Design Twenty-eight cadaveric knees were partially dissected for the examination of the meniscofemoral ligaments. One hundred knee MR examinations were reviewed by two experienced musculoskeletal radiologists. Proximal variations in the meniscofemoral ligaments at MR imaging were classified into three types according to the attachment site: type I, medial femoral condyle; type II, proximal half of the posterior cruciate ligament (PCL); type III, distal half of the PCL. Distal variations were classified into vertical or oblique types according to the orientation of the intermediate signal at the interface of the ligament and lateral meniscus. Results At anatomical study, six cases showed variations in the proximal insertion site of the meniscofemoral ligaments. At MR imaging 93 cases had one or more meniscofemoral ligaments, giving a total of 107 ligaments: 90 ligaments of Wrisberg and 17 ligaments of Humphrey. Forty-one ligaments of Wrisberg were type I, 28 type II, 19 type III, and with two indeterminate type, while 6 ligaments of Humphrey were type I and the remaining 11 were indeterminate. Seven cases showed no meniscofemoral ligament. Of the 107 meniscofemoral ligaments, the distal insertion orientation was of vertical type in 10 ligaments, oblique type in 70 and unidentified in 27. Conclusion An understanding of the high incidence of meniscofemoral ligament variations may help in the interpretation of knee MR studies. (orig.) With 7 figs., 1 tab., 16 refs.

  12. Rare anatomical variation of the musculocutaneous nerve - case report

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    Sergio Ricardo Rios Nascimento

    2016-06-01

    Full Text Available ABSTRACT The clinical and surgical importance of anatomical knowledge of the musculocutaneous nerve and its variations is due to the fact that one of the complications in many upper-limb surgical procedures involves injury to this nerve. During routine dissection of the right upper limb of a male cadaver, we observed an anatomical variation of this nerve. The musculocutaneous nerve originated in the lateral cord and continued laterally, passing under the coracobrachialis muscle and then continuing until its first branch to the biceps brachialis muscle. Just after this, it supplied another two branches, i.e. the lateral cutaneous nerve of the forearm and a branch to the brachialis muscle, and then it joined the median nerve. The median nerve followed the arm medially to the region of the cubital fossa and then gave rise to the anterior intermediate nerve of the forearm. The union between the musculocutaneous nerve and the median nerve occurred approximately at the midpoint of the arm and the median nerve. Given that either our example is not covered by the classifications found in the literature or that it fits into more than one variation proposed, without us finding something truly similar, we consider this variation to be rare.

  13. THE AZYGOS VENOUS SYSTEM AND ITS ANATOMICAL VARIATIONS

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    Madiki Sudhakara Rao

    2016-06-01

    Full Text Available AIMS AND OBJECTIVES Azygos veins are important cavocaval and portacaval junctions, which form a collateral circulation in caval vein occlusion and in portal hypertension, cirrhosis of liver. The unpaired azygos venous system consists of azygos vein, hemiazygos vein and accessory azygos vein. This system of veins, along with its mediastinal, bronchial and oesophageal tributaries drains most of the body wall of trunk, namely posterior abdominal and thoracic wall. Anatomical variations of this unpaired azygos venous system are clinically important. AIMS To study and report the occurrence of anatomical variations of the unpaired azygos venous system in the region of East Godavari District, Andhra Pradesh (India. METHODS The present study was carried out in the Department of Anatomy, KIMS & RF, Amalapuram and G.S.L. Medical College, Rajahmundry over a period of 2 years. The present study was conducted on 60 cadavers (irrespective of age and sex. The entire course of the azygos venous system in these 60 cadavers was carefully observed and documented. RESULTS Anatomical variations were present in 16.66% of cases, out of which three distinct types were identified. 6.6% exhibited two separate azygos venous systems with no communications, 5% with communication between the left brachiocephalic vein and the azygos vein and 5% presence of post-aortic venous channels. CONCLUSION Variations of azygos venous system may be wrongly dubbed as aneurysm, lymphadenopathy or other abnormalities while reporting a CT scan of mediastinum. Venous anomalies are also detected only during surgery. The most troublesome intraoperative hazard is haemorrhage, which is mainly of venous origin. To avoid such situations is to have an awareness and knowledge of the expected venous anomalies.

  14. Sparse decomposition and modeling of anatomical shape variation

    DEFF Research Database (Denmark)

    Sjöstrand, Karl; Rostrup, Egill; Ryberg, Charlotte;

    2007-01-01

    counterparts if constructed carefully. In most medical applications, models are required to have both good statistical performance and a relevant clinical interpretation to be of value. Morphometry of the corpus callosum is one illustrative example. This paper presents a method for relating spatial features to...... anatomical variation related to clinical outcome. In the present application, landmark-based shape data of the corpus callosum is analyzed in relation to age, gender, and clinical tests of walking speed and verbal fluency. To put the data-driven sparse principal component method into perspective, we consider...

  15. Sparse Decomposition and Modeling of Anatomical Shape Variation

    DEFF Research Database (Denmark)

    Sjöstrand, Karl; Rostrup, Egill; Ryberg, Charlotte;

    2007-01-01

    counterparts if constructed carefully. In most medical applications, models are required to have both good statistical performance and a relevant clinical interpretation to be of value. Morphometry of the corpus callosum is one illustrative example. This paper presents a method for relating spatial features to...... anatomical variation related to clinical outcome. In the present application, landmark-based shape data of the corpus callosum is analyzed in relation to age, gender, and clinical tests of walking speed and verbal fluency. To put the data-driven sparse principal component method into perspective, we consider...

  16. Influence of anatomic variations of the middle nasal meathus on sinonasal diseases

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    Buljčik-Čupić Maja M.

    2008-01-01

    50% patients. 4. Variations of the form of ethomoidal bulla in 50% patients. Eives's correlation coefficient i.e. the degree of correlation between sinonasal disorders and the presence of anatomic variation statistically significantly correlate at r >/= ft 05 of anatomic variation of the middle nasal chonha (r =0.23 and the presence of deviation/deformation of nasal septum (r = 0.6 with sinonasal disorders. Discussion and conclusion Anatomic variations of the structures of the middle nasal meatus can additionally complicate the anatomy of the lateral nasal wall and the conditions of the ostiomeatal unit. Therefore we must view these variations as factors predisposing to more rapid and frequent appearance and persistence of chronic inflammations. Also, familiary with the variations in sinonasal anatomy is a prerequisite to safe and effective surgical treatment of sinonasal disease. Recognition of this anatomic variation should minimize catastrophic violation of vital structures such as orbit or skull base.

  17. Variation in stem anatomical characteristics of Campanuloideae species in relation to evolutionary history and ecological preferences.

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    Fritz Hans Schweingruber

    Full Text Available BACKGROUND: The detailed knowledge of plant anatomical characters and their variation among closely related taxa is key to understanding their evolution and function. We examined anatomical variation in 46 herbaceous taxa from the subfamily Campanuloideae (Campanulaceae to link this information with their phylogeny, ecology and comparative material of 56 woody tropical taxa from the subfamily Lobelioideae. The species studied covered major environmental gradients from Mediterranean to Arctic zones, allowing us to test hypotheses on the evolution of anatomical structure in relation to plant competitive ability and ecological preferences. METHODOLOGY/PRINCIPAL FINDINGS: To understand the evolution of anatomical diversity, we reconstructed the phylogeny of studied species from nucleotide sequences and examined the distribution of anatomical characters on the resulting phylogenetic tree. Redundancy analysis, with phylogenetic corrections, was used to separate the evolutionary inertia from the adaptation to the environment. A large anatomical diversity exists within the Campanuloideae. Traits connected with the quality of fibres were the most congruent with phylogeny, and the Rapunculus 2 ("phyteumoid" clade was especially distinguished by a number of characters (absence of fibres, pervasive parenchyma, type of rays from two other clades (Campanula s. str. and Rapunculus 1 characterized by the dominance of fibres and the absence of parenchyma. Septate fibres are an exclusive trait in the Lobelioideae, separating it clearly from the Campanuloideae where annual rings, pervasive parenchyma and crystals in the phellem are characteristic features. CONCLUSIONS/SIGNIFICANCE: Despite clear phylogenetic inertia in the anatomical features studied, the ecological attributes and plant height had a significant effect on anatomical divergence. From all three evolutionary clades, the taller species converged towards similar anatomical structure, characterized by a

  18. Investigations of Anatomical Variations of the Thorax and Heart, and Anatomical Knowledge for First Year Medical Dental and Podiatry Students

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    Verenna, Anne-Marie

    2013-01-01

    The universal presence of anatomy in healthcare professions is undeniable. It is a cornerstone to each of the clinical and basic sciences. Therefore, further expansion of current anatomical knowledge and effective methods to teach anatomy is essential. In this work, the relationship of the dorsal scapular artery with the trunks of the brachial…

  19. Absence of Flexor Carpi Radialis during an Elective Carpometacarpal Arthroplasty of the Thumb: A Rare Anatomical Variation

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    Stratos S. Sofos

    2016-01-01

    Full Text Available Purpose. We present an extremely rare anatomical variation of unilateral flexor carpi radialis (FCR absence. This rare anatomical variation posed a clinical dilemma to us and we highlight the importance of the surgeon being aware of this anatomical variation of an important structure both as a reconstruction tool and as an anatomical landmark. Methods. This anatomical variation of the unilaterally absent FCR was found upon dissection during a carpometacarpal arthroplasty of the thumb. Results. Upon the discovery of an absent FCR tendon, we proceeded with a simple trapeziectomy. Conclusions. We present an extremely rare anatomical variation of unilateral FCR absence. This rare anatomical variation may pose clinical dilemmas to the operating surgeon who aims to utilise the FCR either for tendon transfer, for tendon graft, or, as seen in our case, in the reconstruction of a carpometacarpal excision at the thumb. We highlight this diagnosis of suspicion, which may influence the clinical procedure.

  20. Anatomical variation of abductor pollicis longus in Indian population A cadaveric study

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    Jerina Tewari

    2015-01-01

    Conclusion: Bi-tendinous APL is commonly observed on the dorsal compartment of the wrist in Indian population and these tendon-slips are commonly attached to thefirst metacarpal base and trapezium. This variation must be understood by the Indian Orthopedic surgeons as the response to treatment of DQT and reason forfirst carpo-metacarpal arthritis can be dependent on this anatomical variation.

  1. Normal anatomical variation of the intrahepatic portal vein in Korean

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    Oh, Jae Cheon; Seo, Heung Suk; Kim, Yong Soo; Rhim, Hyun Chul; Koh, Byung Hee; Cho, On Koo; Moon, Won Jin; Lee, Tae Hee [Hanyang Univ., Seoul (Korea, Republic of). Coll. of Medicine

    1997-12-01

    The purpose of this study is to determine the prevalence of variations in the intrahepatic portions of portal veins, as visualized by arterial portograms, and to examine the surgical implications of these findings in Koreans. Five hundred and nineteen arterial portograms of 519 patients with no evidence of vascular tumor invasion or distortion were retrospectively reviewed. In all patients, the main, right, right anterior, right posterior and left portal vein were visualized. On arterial portogram, variations in the intrahepatic portions of the portal veins are frequently seen. The recognition of such variations is important in the preoperative evaluation of patients with hepatic tumors, since the variations may have implications for tumor resection, for the localization of tumor thrombi and in interventional radiologic procedures involving the portal vein. (author).13 refs., 1 tab., 4 figs.

  2. The glenohumeral joint of hominoid primates: locomotor correlates, anatomical variation and evolution

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    Arias Martorell, Júlia

    2014-01-01

    The Doctoral Thesis entitled "the glenohumeral joint of hominoid primates: locomotor Correlates, anatomical variation and evolution" is about the anatomical adaptations in the shoulder joint (glenohumeral joint) of hominoid primates. The action of the forces exerted during locomotion model the shape of the joint determining the range of motion animals can achieve. The hominoid primates stand out as having very mobile joints, with the ability to raise the arm above the shoulder enabling the us...

  3. MORPHOLOGICAL VARIATIONS OF MUSCLE PLANTARIS: ANATOMICAL AND CLINICAL INSIGHT

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    Mohini M Joshi

    2014-10-01

    Full Text Available Background: Plantaris is large muscle in mammals other than primates. Plantaris muscle has long been a subject of much confusion and speculation Evolutionists have speculated on its phylogenetic significance, as a vestigial organ, while surgeons have removed it ‘useless vestige’ to employ its tendon as a spare part for the surgical repair, example tendon transfer operations and reconstruction and as a graft in reconstruction of ligaments etc. In humans it is reduced greatly in size, power, and function and may even be absent. Aim: With this background the aim of the present work is to study morphology, describe the observed variations of the Plantaris muscle, and to discuss the functional significance of Plantaris muscle. Methodology: For the present work 84 limbs available in the department of Anatomy were dissected. The posterior aspect of the knee was dissected using standard surgical equipment and dissection techniques. The Plantaris muscle was isolated and length of fleshy belly and tendon were measured. Any variations in origin, insertion and size were recorded. Result: Mean length of fleshy belly of the Plantaris muscle was 8.39 cm on right side and 8.16 cm on left side. In present study Plantaris muscle was absent 6.66% on right side of the leg; while 12.82 % on left side. In present study variation in insertion of the Plantaris were observed like insertion along medial margin of tendocalcaneus on to calcaneus, in front of tendocalcaneus on to calcaneus, fused to tendocalcaneus and insertion of the Plantaris on deep fascia of leg at the level of ankle. Other variations noted were two bellies of the Plantaris one from lateral supracondylar ridge and other from deep surface of Gastrocnemius, two heads of Plantaris: Both bellies were fused in the lower part producing bipennate arrangement, thin & thick belly of the Plantaris muscle. Variations were also observed in relation to origin that Plantaris muscle originating from deep surface

  4. Quantification and Visualization of Variation in Anatomical Trees

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    Amenta, Nina; Datar, Manasi; Dirksen, Asger; de Bruihne, Marleen; Feragen, Aasa; Ge, Xiaoyin; Holst Pedersen, Jesper; Howard, Marylesa; Owen, Megan; Petersen, Jens; Shi, Jie; Xu, Qiuping

    2015-07-01

    This paper presents two approaches to quantifying and visualizing variation in datasets of trees. The first approach localizes subtrees in which significant population differences are found through hypothesis testing and sparse classifiers on subtree features. The second approach visualizes the global metric structure of datasets through low-distortion embedding into hyperbolic planes in the style of multidimensional scaling. A case study is made on a dataset of airway trees in relation to Chronic Obstructive Pulmonary Disease.

  5. ANATOMICAL VARIATIONS IN SINONASAL REGION IN CASES OF SINUS HEADACHE - CT SCAN - PNS STUDY

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    Arun Kumar

    2015-08-01

    Full Text Available BACKGROUND: Sinus headache secondary to Chronic Rhinosinusitis refers to episode of pain over the sinus area of the face and is often associated with nasal congestion, rhinorrhea, facial pressure, lacrimation, nausea and sensory sensitivity. Any small lesions or anatomical variations over lateral wall of nose may giv e rise to sinus headache. CT scan play a vital role in accurate assessment of osteomeatal complex area and anatomical variations at this site. AIM: To study anatomical variations of osteomeatal complex area and deviated septum in cases of chronic sinus hea dache secondary to Chronic Rhinosinusitis. MATERIALS AND METHODS : This study was conducted in Jhalawar Medical College, ENT Department between Sept. 2012 to Dec. 2014. In this study 75 patients withchronic sinus headache was selected who had chronic headac he for more than 3 months duration not responding to medical line of treatment and who were willing to undergo function endoscopic sinus surgery. All patients underwent for CT scan para nasal sinus. RESULT: In this study deviated nasal septum was found in 77.33% patients, apart from that it was observed that 54.66% of the sinus headache cases had two or more anatomical variations and 28% had single anatomical variations, out of them commonest finding is concha bullosa followed by enlarge bulla ethmoid, para doxical middle turbinate, medialiseduncinate process, lateraliseduncinate process, prominent aggar nasi cells, haller cells and onodi cells in decreasing order . CONCLUSION: The study of CT scan PNS conclude that Deviated Nasal Septum and anatomical variati ons at lateral wall of nose causes narrowing of osteomeatal complex area which predisposed patients to sino nasal disease and sinus headache

  6. ANATOMICAL VARIATION OF PALMARIS LONGUS: TENDINOUS ORIGIN AND FLESHY INSERTION

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    Buddhadeb Ghosh

    2015-03-01

    Full Text Available A tendinous origin and fleshy insertion of palmaris longus muscle was observed in the left forearm during routine dissection which was performed on adult male cadaver in the department of Anatomy, Dr. Rajendra Prasad Government Medical College. It was having long tendinous origin from the medial epicondyle of the humerus and the surrounding deep fascia. It was fusiform at the lower middle of the forearm. The fleshy muscular insertion was noted to the flexor retinaculum and few muscular fibers interdigitate with flexor carpi ulnaris muscle and palmar aponeurosis. The length of tendon was 19 inches and fleshy muscular length was 11inches. The median nerve and ulnar nerve was covered by this fleshy insertion. This palmaris longus variation is helpful for the surgeon and the radiologist, orthopaedic, plastic surgeon during any diagnosis of the forearm because this fleshy part of muscle can compress the median nerve and ulnar nerve or it can be mistaken as a tumor or ganglion during radiological or clinical examination.

  7. Anatomical Variations of Anterior Osteomeatal Complex in Patients With Chronic Sinusitis

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    Sarafraz

    2016-06-01

    Full Text Available Background Identifying predisposing factors for chronic sinusitis is very important. Objectives Anatomical variation of the lateral nasal wall has been investigated in several studies and it has been suggested as a predisposing factor for sinusitis. Patients and Methods In this case-control study, 74 patients who were diagnosed with chronic sinusitis (the case group based on clinical criteria and CT scan were entered into the study and 74 patients without chronic sinusitis were considered as the control group. CT scans of all patients were reviewed by a radiologist to interpret and evaluate anatomic variations of anterior osteomeatal complex including nasal deviation, concha bullosa, agger nasi, lateralized uncinate, Haller’s cells, paradoxical middle turbinate, and maxillary hypoplasia. Data were analyzed using the chi-squared test and Fisher’s exact test with SPSS software version 18. P < 0.05 was considered statistically significant. Results Results showed that the most common sinus involved was maxillary sinus. Among anatomic variations, septal deviation and concha bullosa were associated with chronic sinusitis (P < 0.01 and P < 0.032, respectively. Conclusions Among anatomic variations, septal deviation and concha bullosa are predisposing factors for chronic sinusitis and we recommend that patients with chronic sinusitis be treated by surgical procedures.

  8. An anatomical update on the morphologic variations of S1 and S2.

    Science.gov (United States)

    Karachalios, Theofilos; Zibis, Aristides H; Zintzaras, Elias; Bargiotas, Konstantinos; Karantanas, Apostolos H; Malizos, Konstantinos N

    2010-10-11

    Although percutaneous fixation with iliosacral screws has been shown to be a safe and reproducible method for sacroiliac dislocation and sacral fractures, it is a technically demanding technique, and one of its contraindications is sacral anatomical variations and dysmorphism. The incidence and pattern of S1 and S2 anatomical variations were evaluated in 61 patients (35 women and 26 men) using magnetic resonance imaging of the sacrum in an attempt to explore the possible existence of groups of individuals in whom percutaneous sacroiliac fixation is difficult due to local anatomy. S1 and S2 dimensions in both the transverse and coronal planes were recorded and evaluated. In each individual, S1 and S2 dimensions both in the coronal and transverse planes were proportional, with S2 dimensions being 80% of those of S1 on average. Patients were separated into 4 groups based on the S1 and S2 body size and the asymmetry of dimensions in the transverse and coronal planes. In 48 patients (78.6%), dimensions in both planes were symmetrical despite the varying size of the S1 and S2 body. In 2 patients (3.3%) there was a combination of large transverse plane and small coronal plane dimensions, with large S1 and S2 body size. In 9 patients (14.8%), coronal plane dimensions were disproportionately smaller compared to those of the transverse plane, with a varying size of S1 and S2 body making effective sacroiliac screw insertion a difficult task. Thus, a preoperative imaging study, preferably computed tomography scan, of S1 and S2 body size and coronal plane dimensions and an intraoperative fluoroscopic control of S1 and S2 dimensions on the coronal plane are suggested for safe sacroiliac screw fixation.

  9. ANATOMICAL VARIATIONS IN CONDUIT OF VERTEBRAL ARTERY IN ATLAS

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    Krishna

    2013-10-01

    Full Text Available ABSTRACT : BACKGROUND: The 1 st cervical vertebra is named as atlas. It differs from all the other vertebrae in having no body and no spine. The atlas consists of two bulky lateral masses, connected to each other in front by a short anterior arch, and behind by a long curved posterior arch it thus forms a ring of bone. The posterior arch forms three - fifths of the atlantal ring. At the r oot of the arch the superior surface of posterior arch bears a wide groove for the vertebral artery, venous plexus and the C1 nerve immediately behind the lateral mass. In few cases this groove is converted into the completely or partially posterior/latera l vertebral artery foramen. AIM : This study was carried out to know the variations in posterior vertebral artery groove in atlas vertebra for clinical and surgical purpose. MATERIALS AND METHODS: The present study is based on the observation of the 300 mac erated Human atlas vertebrae of North Indian present in the Anthropology Museum of Department of Anatomy, GSVM Medical College, Kanpur. The atlases were randomly selected the age and sex were not taken into consideration. RESULTS: We observed the complete posterior vertebral artery foramen in 8% specimen (2.33% bilateral and 5.67% unilateral. In 3.33% it was found on left side and 2.33% on right side. Incidence of incomplete posterior vertebral artery foramen was observed in 9.33% (1.33% bilateral and 8% u nilateral. In 5% it was found on left side and 3% on right side. The bilateral presence of complete or incomplete lateral vertebral artery foramen was nil. The unilateral presence of complete or incomplete lateral vertebral artery foramen was found equal in frequency i.e. 0.67%. The unilateral presence of complete lateral vertebral artery foramen on either side was found in 0.33% specimen whereas the incomplete lateral vertebral artery foramen was found only on left side (0.67%. CONCLUSION : The presence o f complete/incomplete posterior or lateral

  10. HPV Vaccine Effective at Multiple Anatomic Sites

    Science.gov (United States)

    A new study from NCI researchers finds that the HPV vaccine protects young women from infection with high-risk HPV types at the three primary anatomic sites where persistent HPV infections can cause cancer. The multi-site protection also was observed at l

  11. Accessory mental foramen: A rare anatomical variation detected by cone-beam computed tomography

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    Torres, Marianna Guanaes Gomes; De Faro Valverde, Ludmila; Vidal, Manuela Torres Andion; Crusoe-Rebello, Ieda Margarida [Dept. of Oral Radiology, School of Dentistry, Federal University of Bahia, Salvador (Brazil)

    2015-03-15

    The mental foramen is a bilateral opening in the vestibular portion of the mandible through which nerve endings, such as the mental nerve, emerge. In general, the mental foramen is located between the lower premolars. This region is a common area for the placement of dental implants. It is very important to identify anatomical variations in presurgical imaging exams since damage to neurovascular bundles may have a direct influence on treatment success. In the hemimandible, the mental foramen normally appears as a single structure, but there are some rare reports on the presence and number of anatomical variations; these variations may include accessory foramina. The present report describes the presence of accessory mental foramina in the right mandible, as detected by cone-beam computed tomography before dental implant placement.

  12. Anatomical variation of thyroid veins on contrast-enhanced multi-detector row computed tomography

    International Nuclear Information System (INIS)

    Highlights: • This is the first study to demonstrate the anatomy of thyroid veins on contrasted-enhanced MDCT. • Identifying the thyroid vein on MDCT prior to selective venous sampling of parathyroid hormone provides clinical information to interventional radiologist. • Detecting especially the inferior thyroid veins with individual variability in numbers, locations, and lengths may have an effect on SVS for HPT and decrease the difficulty and time of the procedure. - Abstract: Objective: The objective of this study was to clarify the anatomical variation of thyroid veins into the systemic vein using contrast-enhanced multi-detector row computed tomography (MDCT). Design and methods: : The subjects were 80 patients (34 males and 46 females; mean age, 50.1 years; age range, 15–92 years) with neck diseases who underwent MDCT. The number and location of inflow points of the thyroid veins into the systemic vein, and the length from the junction of bilateral brachiocephalic veins to the orifice of inferior thyroid vein were investigated by reviewing the axial and coronal images. Results: All superior thyroid veins were detected. Right and left middle thyroid veins were identified in 39 and 29 patients, respectively. Right inferior thyroid veins, left inferior thyroid veins, and common trunks were detected in 43, 46, and 39 patients, respectively; in five patients, two left thyroid veins were identified. All left inferior thyroid veins and 34 common trunks flowed into the innominate vein, while right ones had some variations in inflow sites. Mean lengths were 3.01 ± 1.30 cm (range, 0.5–6.19) and 2.04 ± 0.91 cm (0.5–4.4) in the left inferior thyroid vein and common trunk, and 1.96 ± 1.05 cm (0.81–4.8) and 1.65 ± 0.69 cm (0.63–2.94) in the right one flowing into the right internal jugular vein and the innominate vein, respectively. Conclusions: The numbers and orifices of thyroid veins were identified at high rates on contrast-enhanced MDCT. This

  13. Anatomical variation of thyroid veins on contrast-enhanced multi-detector row computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Tomita, Hayato, E-mail: m04149@yahoo.co.jp [Department of Radiology, St. Marianna University School of Medicine, Yokohama City Seibu Hospital, 1197-1 Yasashicho, Asahi-ku, Yokohama, Kanagawa 241-0811 (Japan); Yamada, Takayuki; Murakami, Kenji; Hashimoto, Kazuki; Tazawa, Yoko; Kumano, Reiko [Department of Radiology, St. Marianna University School of Medicine, Yokohama City Seibu Hospital, 1197-1 Yasashicho, Asahi-ku, Yokohama, Kanagawa 241-0811 (Japan); Nakajima, Yasuo [Department of Radiology, St. Marianna University School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511 (Japan)

    2015-05-15

    Highlights: • This is the first study to demonstrate the anatomy of thyroid veins on contrasted-enhanced MDCT. • Identifying the thyroid vein on MDCT prior to selective venous sampling of parathyroid hormone provides clinical information to interventional radiologist. • Detecting especially the inferior thyroid veins with individual variability in numbers, locations, and lengths may have an effect on SVS for HPT and decrease the difficulty and time of the procedure. - Abstract: Objective: The objective of this study was to clarify the anatomical variation of thyroid veins into the systemic vein using contrast-enhanced multi-detector row computed tomography (MDCT). Design and methods: : The subjects were 80 patients (34 males and 46 females; mean age, 50.1 years; age range, 15–92 years) with neck diseases who underwent MDCT. The number and location of inflow points of the thyroid veins into the systemic vein, and the length from the junction of bilateral brachiocephalic veins to the orifice of inferior thyroid vein were investigated by reviewing the axial and coronal images. Results: All superior thyroid veins were detected. Right and left middle thyroid veins were identified in 39 and 29 patients, respectively. Right inferior thyroid veins, left inferior thyroid veins, and common trunks were detected in 43, 46, and 39 patients, respectively; in five patients, two left thyroid veins were identified. All left inferior thyroid veins and 34 common trunks flowed into the innominate vein, while right ones had some variations in inflow sites. Mean lengths were 3.01 ± 1.30 cm (range, 0.5–6.19) and 2.04 ± 0.91 cm (0.5–4.4) in the left inferior thyroid vein and common trunk, and 1.96 ± 1.05 cm (0.81–4.8) and 1.65 ± 0.69 cm (0.63–2.94) in the right one flowing into the right internal jugular vein and the innominate vein, respectively. Conclusions: The numbers and orifices of thyroid veins were identified at high rates on contrast-enhanced MDCT. This

  14. MDCT angiography of anatomical variations of the celiac trunk and superior mesenteric artery

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    Ognjanović Neda

    2014-01-01

    Full Text Available The aim of this study was to detect and describe the existence and incidence of anatomical variations of the celiac trunk and superior mesenteric artery. The study was conducted on 150 persons, who underwent abdominal Multi- Detector Computer Tomography (MDCT angiography, from April 2010 until November 2012. CT images were obtained with a 64-row MDCT scanner in order to analyze the vascular anatomy and anatomical variations of the celiac trunk and superior mesenteric artery. In our study, we found that 78% of patients have a classic anatomy of the celiac trunk and superior mesenteric artery. The most frequent variation was the origin of the common hepatic artery from the superior mesenteric artery (10%. The next variation, according to frequency, was the origin of the left gastric artery direct from the abdominal aorta (4%. The arc of Buhler as an anastomosis between the celiac trunk and superior mesenteric artery, was detected in 3% of cases, as was the presence of a common trunk of the celiac trunk and superior mesenteric artery (in 3% of cases. Separate origin of the splenic artery and the common hepatic artery was present in 2% of patients. The MDCT scanner gives us an insight into normal anatomy and variations of the abdominal blood vessels, which is very important in the planning of surgical interventions, especially transplantation, as well as in the prevention of complications due to ischemia.

  15. Anatomical Variations of the Circle of Willis in Males and Females on 3D MR Angiograms

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    Kawther A. Hafez, Nahla M. Afifi, Fardous Z. Saudi

    2007-03-01

    Full Text Available Objective: The objective of the present work was to study the anatomical variations of the circle of Willis as regard its component vessels and their average diameters in a sample of adult Egyptians and to detect any sex-related differences in these variations. Material and Methods: One hundred and twenty adult patients were observed (60 males and 60 females. They all had problems unrelated to any ischemic or vascular diseases, so they were considered as healthy control, concerning the morphology of the circle of Willis. In addition, ten cadavers' brains were obtained from the Anatomy department, Faculty of Medicine Ain Shams University for examination of the circle of Willis and for detection of any variations. Results: The anatomical variations of the anterior part, posterior part and completeness of the circle were inspected. Also, the diameters of all component vessels were assessed. The results indicated that, the anterior part of the circle was completed in 70% males and 75% females of the study sample. No statistically significant difference was detected between sexes. The most common variant of the anterior part was the single anterior communicating artery followed by the hypoplastic or absent anterior communicating artery. The posterior part of the circle was completed in 44% males and 58% females. The most common variant was the bilateral posterior communicating arteries, followed by the unilateral posterior communicating artery. An entirely complete circle was found only in 45% of the entire population; and it was higher in the females than the in males. The vessels diameters were smaller in the females than in the males, except for the diameter of the posterior communicating artery. Cadavers' examination revealed six cases with complete circle, 3 cases of unilateral fetal posterior communicating and one case of absent posterior communicating artery. Conclusion: The present study showed the amazing great variability of the anatomy of

  16. Anatomical variations of nose and para-nasal sinuses; CT scan review

    International Nuclear Information System (INIS)

    Objective: To determine the frequency of anatomic variations on computed tomography scan of para-nasal sinuses. Methods: The retrospective study was conducted at the Aga Khan University Hospital, Karachi, and comprised computed tomography scans of 77 patients who had presented between October 2007 and March 2011. All the scans were reviewed using Picture Archiving Communication System computer software. The scans were reviewed for the presence of deviated nasal septum, paradoxical middle turbinate, Haller cell, Onodi cell, and pneumatisation of the middle turbinate and uncinate process. Results: The mean age of the patients was 31+-13.15 years. One or more types of anatomical variants were observed in 40 (51.9%) of the patients; the most frequent being the deviated nasal septum 20 (26%) and the Concha bullosa 14 (18.2%). Conclusion: Considering the wide range of variations in the anatomy, each and every para-nasal sinus case should be planned individually and carefully to avoid dreadful complications and maximise patients benefit. (author)

  17. Anatomical variations in wood among four native species of Leguminosae grown in arid areas of China

    Institute of Scientific and Technical Information of China (English)

    Yang Shu-min; Jiang Ze-hui; Ren Hai-qing; Ikuo Furukawa

    2007-01-01

    Morphological features and anatomical variations are described and illustrated in detail for four native species of Leguminosae grown in arid sandy regions in China, which are Hedysarum scoparium Fisch.et Mey., Caragana korshiskii Kom., Lespedeza bicolor Turcz. and Ammopiptanthus mongolicus (Maxim. ex Kom.) Cheng f. All species showed similar morphological features:distinct growth ring boundaries, ring to semi-ring-porosity, simple perforation plates, alternate intervessel pitting, nonseptate fibers,paratracheal confluent axial parenchyma, helical thickenings and heterocellular rays. However, the vessel arrangement and their quantitative features were different. A. mongolicus had smaller vessel diameters and larger vessel frequency, while the values in the other three species were similar, but bigger than those in A. mongolicus. The variation of vessel lengths and fiber lengths along a horizontal direction showed an irregular tendency. There were significant differences in both fiber lengths and vessel element lengths among trees and within trees, except for A. mongolicus. The relationships between anatomical features of secondary xylem and the adaptability of these species to desert environments are also discussed.

  18. Underlying sources of cognitive-anatomical variation in multi-modal neuroimaging and cognitive testing

    Science.gov (United States)

    Watson, P.D.; Paul, E.J.; Cooke, G.E.; Ward, N.; Monti, J.M.; Horecka, K.M.; Allen, C.M.; Hillman, C.H.; Cohen, N.J.; Kramer, A.F.; Barbey, A.K.

    2016-01-01

    Healthy adults have robust individual differences in neuroanatomy and cognitive ability not captured by demographics or gross morphology (Luders, Narr, Thompson, & Toga, 2009). We used a hierarchical independent component analysis (hICA) to create novel characterizations of individual differences in our participants (N = 190). These components fused data across multiple cognitive tests and neuroanatomical variables. The first level contained four independent, underlying sources of phenotypic variance that predominately modeled broad relationships within types of data (e.g., “white matter,” or “subcortical gray matter”), but were not reflective of traditional individual difference measures such as sex, age, or intracranial volume. After accounting for the novel individual difference measures, a second level analysis identified two underlying sources of phenotypic variation. One of these made strong, joint contributions to both the anatomical structures associated with the core fronto-parietal “rich club” network (van den Heuvel & Sporns, 2011), and to cognitive factors. These findings suggest that a hierarchical, data-driven approach is able to identify underlying sources of individual difference that contribute to cognitive-anatomical variation in healthy young adults. PMID:26808332

  19. Anatomical Variations of Cystic Ducts in Magnetic Resonance Cholangiopancreatography and Clinical Implications

    Science.gov (United States)

    Sarawagi, Radha; Sundar, Shyam; Gupta, Sanjeev K.; Raghuwanshi, Sameer

    2016-01-01

    Background. Anatomical variations of cystic duct (CD) are frequently unrecognized. It is important to be aware of these variations prior to any surgical, percutaneous, or endoscopic intervention procedures. Objectives. The purpose of our study was to demonstrate the imaging features of CD and its variants using magnetic resonance cholangiopancreatography (MRCP) and document their prevalence in our population. Materials and Methods. This study included 198 patients who underwent MRCP due to different indications. Images were evaluated in picture archiving communication system (PACS) and variations of CD were documented. Results. Normal lateral insertion of CD at middle third of common hepatic duct was seen in 51% of cases. Medial insertion was seen in 16% of cases, of which 4% were low medial insertions. Low insertion of CD was noted in 9% of cases. Parallel course of CD was present in 7.5% of cases. High insertion was noted in 6% and short CD in 1% of cases. In 1 case, CD was draining into right hepatic duct. Congenital cystic dilation of CD was noted in one case with evidence of type IV choledochal cyst. Conclusion. Cystic duct variations are common and MRCP is an optimal imaging modality for demonstration of cystic duct anatomy. PMID:27313891

  20. Anatomical Variations in the Sinoatrial Nodal Artery: A Meta-Analysis and Clinical Considerations.

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    Jens Vikse

    Full Text Available The sinoatrial nodal artery (SANa is a highly variable vessel which supplies blood to the sinoatrial node (SAN. Due to its variability and susceptibility to iatrogenic injury, our study aimed to assess the anatomy of the SANa and determine the prevalence of its anatomical variations.An extensive search of major electronic databases was performed to identify all articles reporting anatomical data on the SANa. No lower date limit or language restrictions were applied. Anatomical data regarding the artery were extracted and pooled into a meta-analysis.Sixty-six studies (n = 21455 hearts were included in the meta-analysis. The SANa usually arose as a single vessel with a pooled prevalence of 95.5% (95%CI:93.6-96.9. Duplication and triplication of the artery were also observed with pooled prevalence of 4.3% (95%CI:2.8-6.0 and 0.3% (95%CI:0-0.7, respectively. The most common origin of the SANa was from the right coronary artery (RCA, found in 68.0% (95%CI:55.6-68.9 of cases, followed by origin from the left circumflex artery, and origin from the left coronary artery with pooled prevalence of 22.1% (95%CI:15.0-26.2 and 2.7 (95%CI:0.7-5.2, respectively. A retrocaval course of the SANa was the most common course of the artery with a pooled prevalence of 47.1% (95%CI:36.0-55.5. The pooled prevalence of an S-shaped SANa was 7.6% (95%CI:2.9-14.1.The SANa is most commonly reported as a single vessel, originating from the RCA, and taking a retrocaval course to reach the SAN. Knowledge of high risk anatomical variants of the SANa, such as an S-shaped artery, must be taken into account by surgeons to prevent iatrogenic injuries. Specifically, interventional or cardiosurgical procedures, such as the Cox maze procedure for atrial fibrillation, open heart surgeries through the right atrium or intraoperative cross-clamping or dissection procedures during mitral valve surgery using the septal approach can all potentiate the risk for injury in the setting of high

  1. Anatomical Variation of the Maxillary Sinus in Cone Beam Computed Tomography

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    Marcelo Lupion Poleti

    2014-01-01

    Full Text Available Purpose. The aim of this paper is to report a case in which the cone beam computed tomography (CBCT was important for the confirmation of the presence of maxillary sinus septum and, therefore, the absence of a suspected pathologic process. Case Description. A 27-year-old male patient was referred for the assessment of a panoramic radiograph displaying a radiolucent area with radiopaque border located in the apical region of the left upper premolars. The provisional diagnosis was either anatomical variation of the maxillary sinuses or a bony lesion. Conclusion. The CBCT was important for an accurate assessment and further confirmation of the presence of maxillary septum, avoiding unnecessary surgical explorations.

  2. Some anatomical variation of paranasal sinuses using sinus endoscopic approach on "cadaver" in Isfahan, Iran

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    Nezamoddin Berjis

    2014-01-01

    Full Text Available Background: Due to the anatomical variations of the paranasal sinuses and its great importance in sinus surgery, as this area is in very close proximity to vital structures including the optic nerve, carotid artery, and skull base, anatomical knowledge of this area is of high importance. The purpose of this study is defining a full and clear impression of paranasal sinus anatomy and its variations as a model for the human population of the country. Materials and Methods: This study was conducted on 45 cadavers in Isfahan forensic Medicine center during 2010 to 2011. Nasal and paranasal sinuses endoscopic dissection was done with (zero and 30 o lenses (Olympus. The methods of performed dissection were via the Stamberger technique. Results: This study showed that 88.9% (40 cases of middle turbinates were in a typical form, while 6.7% (3 cases were in medial and only 4.4% (2 cases were in the lateral form. We also observed 88.9% (40 cases with Agger nasi cells, 37.8% (17 cases with Onodi cells, 28.9% cases with accessory Ostia of maxillary sinus (13 cases, and 15.6% of the cases (7 cases with concha bullosa. The position of the maxillary sinus ostium was as follows. The inferior 1/3 of hiatus semilunaris in 38 (84.5%, superior 1/3 of hiatus semilunaris in 4 (4.4%, middle 1/3 of hiatus semilunaris in 5 (11.1%. The sphenoid ostia in 53.3% (24 cases were slit shape, 28.9% (13 cases oval, and 17.8% (18 cases were round shape. Conclusion : Our survey showed that the distance between anterior nasal spine and anterior wall of the sphenoid sinus was within 7.6 ± 0.2 cm SD.

  3. A STUDY OF ANATOMICAL VARIATIONS OF THE COMMON CAROTID ARTERIES: A CADAVERIC STUDY

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    Vatsala A R

    2014-03-01

    Full Text Available Background: Anatomical variations of carotid arterial system which are not infrequently encountered have a great impact on the surgical approaches of the neck. Although the described individual variations of the carotid arteries are well-known in the literature, the combination of anomalies reported in this study has not been, to the best of our knowledge, previously described. The carotid arteries show important variability and thus emphasise caution for clinicians during surgical procedures in the neck. Methods:The present study was undertaken on 80 common carotid arteries (40 left, 40 right of both sexes from embalmed adult human cadavers. The specimens were studied by detailed dissection method. Results: In the present study,fiftyone (63.8% bifurcations of common carotid arteries were high among which the most common levels of bifurcation was at the level of C 3 vertebral body (37.5%. The origin of the right common carotid artery was high and low in 10% and 2.6% of vessels respectively. Conclusion: The carotid arteries show important variability and thus emphasise caution for clinicians during surgical procedures in the neck.

  4. Anatomical Study of the Ulnar Nerve Variations at High Humeral Level and Their Possible Clinical and Diagnostic Implications

    Science.gov (United States)

    Guru, Anitha; Kumar, Naveen; Ravindra Shanthakumar, Swamy; Patil, Jyothsna; Nayak Badagabettu, Satheesha; Aithal Padur, Ashwini; Nelluri, Venu Madhav

    2015-01-01

    Background. Descriptive evaluation of nerve variations plays a pivotal role in the usefulness of clinical or surgical practice, as an anatomical variation often sets a risk of nerve palsy syndrome. Ulnar nerve (UN) is one amongst the major nerves involved in neuropathy. In the present anatomical study, variations related to ulnar nerve have been identified and its potential clinical implications discussed. Materials and Method. We examined 50 upper limb dissected specimens for possible ulnar nerve variations. Careful observation for any aberrant formation and/or communication in relation to UN has been carried out. Results. Four out of 50 limbs (8%) presented with variations related to ulnar nerve. Amongst them, in two cases abnormal communication with neighboring nerve was identified and variation in the formation of UN was noted in remaining two limbs. Conclusion. An unusual relation of UN with its neighboring nerves, thus muscles, and its aberrant formation might jeopardize the normal sensori-motor behavior. Knowledge about anatomical variations of the UN is therefore important for the clinicians in understanding the severity of ulnar nerve neuropathy related complications. PMID:26246909

  5. Anatomical Study of the Ulnar Nerve Variations at High Humeral Level and Their Possible Clinical and Diagnostic Implications

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    Anitha Guru

    2015-01-01

    Full Text Available Background. Descriptive evaluation of nerve variations plays a pivotal role in the usefulness of clinical or surgical practice, as an anatomical variation often sets a risk of nerve palsy syndrome. Ulnar nerve (UN is one amongst the major nerves involved in neuropathy. In the present anatomical study, variations related to ulnar nerve have been identified and its potential clinical implications discussed. Materials and Method. We examined 50 upper limb dissected specimens for possible ulnar nerve variations. Careful observation for any aberrant formation and/or communication in relation to UN has been carried out. Results. Four out of 50 limbs (8% presented with variations related to ulnar nerve. Amongst them, in two cases abnormal communication with neighboring nerve was identified and variation in the formation of UN was noted in remaining two limbs. Conclusion. An unusual relation of UN with its neighboring nerves, thus muscles, and its aberrant formation might jeopardize the normal sensori-motor behavior. Knowledge about anatomical variations of the UN is therefore important for the clinicians in understanding the severity of ulnar nerve neuropathy related complications.

  6. Anatomic variation of the clavicle: A novel three-dimensional study.

    LENUS (Irish Health Repository)

    Daruwalla, Zubin J

    2010-03-01

    An understanding of the complex anatomy of the clavicle is helpful in the treatment of clavicular fractures. Using three-dimensional (3D) statistical shape analysis, the author presents a novel method to assess geometric morphology of the clavicle. Fifteen fresh frozen shoulder specimens were scanned using high-resolution computerized tomography (CT) but four were excluded from the study. A further 16 high-resolution CT scans of the clavicle were obtained by searching the hospital database. All 27 scans were reconstructed and subsequently imported into and analyzed using a specifically developed statistical software package. Using statistical shape analysis, geometric parameters were then measured. Both gender as well as side specific geometric morphology were observed. Clavicles in men were longer, wider, and thicker than in women. Right clavicles had a greater medial depth than left clavicles, especially in women. Clavicles in men had a greater lateral depth than in women. The sternal angle in women was larger than in men. Using 3D statistical shape analysis and applying it to the clavicle standardizes the study of its anatomy, rules out any variability, and calculates morphological parameters that are accurate, precise, and reproducible. This unique approach provides information that is useful not only to the clinician but also in the modification of current or design of future clavicle fixation devices. More importantly, from an anatomy standpoint, implementation of this novel approach in anatomical studies would eliminate intra- and interobserver variation and allow all studies to be standardized and thus more comparable.

  7. Genetic variation of hydraulic and wood anatomical traits in hybrid poplar and trembling aspen.

    Science.gov (United States)

    Schreiber, Stefan G; Hacke, Uwe G; Hamann, Andreas; Thomas, Barb R

    2011-04-01

    Intensive forestry systems and breeding programs often include either native aspen or hybrid poplar clones, and performance and trait evaluations are mostly made within these two groups. Here, we assessed how traits with potential adaptive value varied within and across these two plant groups. Variation in nine hydraulic and wood anatomical traits as well as growth were measured in selected aspen and hybrid poplar genotypes grown at a boreal planting site in Alberta, Canada. Variability in these traits was statistically evaluated based on a blocked experimental design. We found that genotypes of trembling aspen were more resistant to cavitation, exhibited more negative water potentials, and were more water-use-efficient than hybrid poplars. Under the boreal field test conditions, which included major regional droughts, height growth was negatively correlated with branch vessel diameter (Dv ) in both aspen and hybrid poplars and differences in Dv were highly conserved in aspen trees from different provenances. Differences between the hybrid poplars and aspen provenances suggest that these two groups employ different water-use strategies. The data also suggest that vessel diameter may be a key trait in evaluating growth performance in a boreal environment.

  8. ANATOMICAL VARIATIONS FINDINGS ON CONE BEAM-COMPUTED TOMOGRAPHY IN CLEFT LIP AND PALATE PATIENTS

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    Yllka DECOLLI

    2015-09-01

    Full Text Available Introduction: Cone beam computed tomography (CBCT is frequently used in surgery treatment planning in patients with cleft lip and palate (CLP. The aim of this study was to investigate the presence of different anatomical variations of patients with cleft lip and palate using CBCT images. Materials and method: CBCTs taken from consecutive patients (n =25; mean age 10.7±4 years, range 6.5–23 years with a non-syndromic cleft lip and palate (CLP, between June 2014-2015, were systematically evaluated. Sinuses, nasopharynx, oropharynx, hypopharynx, temporo-mandibular joint (TMJ, maxilla and mandible were checked for incidental findings. Results: On 90.1 % of the CBCTs, incidental findings were found. The most prevalent ones were airway/sinus findings (78.1%, followed by dental problems, e.g. missing teeth (54%, nasal septum deviation (93%, middle ear and mastoid opacification, suggestive for otitis media (8% and (chronic mastoiditis (7%, abnormal TMJ anatomy (4.3%. Conclusions: Incidental findings are common on CBCTs in cleft lip and palate patients. Compared with the literature, CLP patients have more dental, nasal and ear problems. The CBCT scan should be reviewed by all specialists in the CLP team, stress being laid on their specific background knowledge concerning symptoms and treatment of these patients.

  9. Anatomical Study of Variation of Vertebral Artery Entering the Foramen Transversarium of Cervical Vertebrae

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    Rawal Jitendra D

    2012-04-01

    Full Text Available Introduction: The vertebral artery is unique among the cervico-cephalic vessels by virtue of its position and relationship to the adjacent structures. The advent of new techniques and materials for surgical treatment of lower cervical spinal condition has come along with possible potential complications. As vertebral artery normally passes through transverse foramen of sixth cervical vertebra, these procedures can safely be done on seventh cervical vertebra. Aim: To study the anatomical variation of vertebral artery entering the transverse foramen of cervical vertebrae. Material & Methods: 50 vertebral arteries were dissected in 25 embalmed cadavers, out of which 19 cadavers were male and 6 were female. Vertebral artery was dissected from its origin to its entry into foramen magnum. Results: 4 (8 % cases were found where vertebral artery entered into transverse foramen of 7th cervical vertebrae out of which 1 was bilateral, and 2 was on left side. In 46 cases (92% it entered through transverse foramen of 6th cervical vertebrae. Conclusion: In 8% cases as vertebral artery enters through C7 transverse foramina, the relation is important while performing transpedicular fixation or other spinal surgeries. [National J of Med Res 2012; 2(2.000: 199-201

  10. ANATOMIC STUDY OF THE PROXIMAL THIRD OF THE FEMUR: FEMOROACETABULAR IMPACT AND THE CAM EFFECT

    Science.gov (United States)

    Labronici, Pedro José; Alves, Sergio Delmonte; da Silva, Anselmo Fernandes; Giuberti, Gilberto Ribeiro; de Azevedo Neto, Justino Nóbrega; Mezzalira Penedo, Jorge Luiz

    2015-01-01

    To analyze anatomical variations of the proximal end of femur that could cause a femoroacetabular impact. Methods: 199 skeletically mature anatomical specimens of femurs were used. The femurs were measured in order to determine the anteversion angle of the femoral neck, neckshaft angle, sphericity of the femoral head at anteroposterior and superoinferior, angle between epiphysis and the anterior femoral neck, angle between epiphysis and the neck at lateral plane, anteroposterior distance at 5mm of the head and neck junction and anteroposterior distance of the neck base. Results: we found that the impact subgroup presented a significantly larger junction diameter of 5mm (p = 0.0001) and cam-head (%) (p= 0.0001), while base-cam (%) (p = 0.0001) showed a significantly smaller diameter than the subgroup without impact. It was identified that cam-head (%) ≤ 80 e base-cam (%) ≤ 73 were identified as the optimal impact points. Conclusion: our study showed that the effect cam, caused by anatomical variations of the proximal femoral end focused the head-neck junction and base of the neck-junction head-neck. These rates can be predictive factors of the impact. PMID:26998462

  11. Tendon of the long head of the biceps originating from the rotator cuff - An uncommon anatomical variation: case report

    Directory of Open Access Journals (Sweden)

    Carlos Vicente Andreoli

    2016-02-01

    Full Text Available ABSTRACT Anatomical variations at the origin of the biceps tendon have been described by several authors, but occurrences of an origin in the supraspinatus are rare. It is unclear whether this variation might contribute toward pathological conditions of the shoulder. Our objective here was to describe a case of an anatomical variation in the origin of the tendon of the long head of the biceps. The clinical information, preoperative images and arthroscopic images relating to a patient with an aberrant origin of the long head of the biceps, which was observed during shoulder arthroscopy, were reviewed. In this case study, the origin of the biceps was found in the rotator cuff, without any origin from the supraglenoid tubercle or upper labrum. This variant did not seem to contribute toward the pathological condition of the shoulder, and standard treatment for the concomitant condition was sufficient for treating it.

  12. Tendon of the long head of the biceps originating from the rotator cuff – An uncommon anatomical variation: case report☆

    Science.gov (United States)

    Andreoli, Carlos Vicente; Esteves, Leonardo Roure; Figueiredo, Eduardo; Belangero, Paulo Santoro; de Castro Pochini, Alberto; Ejnisman, Benno

    2015-01-01

    Anatomical variations at the origin of the biceps tendon have been described by several authors, but occurrences of an origin in the supraspinatus are rare. It is unclear whether this variation might contribute toward pathological conditions of the shoulder. Our objective here was to describe a case of an anatomical variation in the origin of the tendon of the long head of the biceps. The clinical information, preoperative images and arthroscopic images relating to a patient with an aberrant origin of the long head of the biceps, which was observed during shoulder arthroscopy, were reviewed. In this case study, the origin of the biceps was found in the rotator cuff, without any origin from the supraglenoid tubercle or upper labrum. This variant did not seem to contribute toward the pathological condition of the shoulder, and standard treatment for the concomitant condition was sufficient for treating it. PMID:26962493

  13. Variation in the wood anatomical structure of Gmelina arborea (Verbenaceae) trees at different ecological conditions in Costa Rica.

    Science.gov (United States)

    Moya, Róger; Tomazello Fo, Mario

    2008-06-01

    The tree Gmelina arborea has been widely introduced in Costa Rica for commercial purposes. This new conditions for melina cause variations on anatomy in secondary xylem of the trees growing in plantations. The objective of the present research was to determine the variation in the anatomy of xylem caused by the ecological conduction variation. Dimensions of fiber, axial parenchyma percentage of cross sections, parameters of vessels and the ray were measured. The results showed that some anatomical characteristics remained stable despite variations of ecological conditions, especially radial parenchyma and anatomical features which were less affected by the altitude. On the other hand, the vessels, axial parenchyma and fiber were less stable because they were affected significantly by the longitude, latitude, altitude and precipitation. Latitude significantly affected vessel percentage, length and diameter of the fiber and lumen. Longitude affected vessel percentage and fiber diameter. Altitude had a significant correlation with the amount of cells at ray height. Annual average precipitation affected vessel percentage and diameter, not only of the fiber, but also of the lumen. These results suggest that the new growth conditions of G. arborea trees in Costa Rica have produced an anatomic adaptation. PMID:19256437

  14. Anatomic variations of superficial peroneal nerve: clinical implications of a cadaver study.

    Science.gov (United States)

    Prakash; Bhardwaj, Ajay Kumar; Singh, Deepak Kumar; Rajini, T; Jayanthi, V; Singh, Gajendra

    2010-01-01

    Superficial peroneal nerve and its branches are frequently at risk for iatrogenic damage. Although different studies on anatomical variations of superficial peroneal nerve are available in the medical literature, such reports are rare from India. Hence the present study was undertaken on Indian population. A total of 60 specimens of inferior extremities from 30 properly embalmed and formalin fixed cadavers were dissected and examined for the location and course of the superficial peroneal nerve including number, level, course and distributions of branches. The superficial peroneal nerve in 28.3% specimens was located in the anterior compartment of the leg. In 8.3% specimens the superficial peroneal nerve branched before piercing between the peroneus longus and extensor digitorum longus muscle whereas in 11.7% specimens it branched after piercing the aforementioned muscles and before piercing the deep fascia. In 41 out of 60 specimens the sensory division of superficial peroneal nerve branched into the medial dorsal cutaneous nerve and intermediate dorsal cutaneous nerve distal to its emergence from the deep fascia and proximal to its relation to the extensor retinaculum. In 20 out of 60 specimens the accessory deep peroneal nerve, an additional branch from the sensory division of superficial peroneal nerve, through its course in the anterior compartment of the leg passed deep to the extensor retinaculum and supplied the ankle and the dorsum of foot. Hopefully the present study will help in minimizing iatrogenic damage to the superficial peroneal nerve and its branches while performing arthroscopy, local anesthetic block, surgical approach to the fibula, open reduction and internal fixation of lateral malleolar fractures, application of external fixators, elevation of a fasciocutaneous or fibular flaps for grafting, surgical decompression of neurovascular structures, or miscellaneous surgery on leg, foot and ankle.

  15. An ``Anatomic approach" to study the Casimir effect

    Science.gov (United States)

    Intravaia, Francesco; Haakh, Harald; Henkel, Carsten

    2010-03-01

    The Casimir effect, in its simplest definition, is a quantum mechanical force between two objects placed in vacuum. In recent years the Casimir force has been the object of an exponentially growing attention both from theorists and experimentalists. A new generation of experiments paved the way for new challenges and spotted some shadows in the comparison to theory. Here we are going to isolate different contributions to the Casimir interaction and perform a detailed study to shine new light on this phenomenon. As an example, the contributions of Foucault (eddy current) modes will be discussed in different configurations. This ``anatomic approach'' allows to clearly put into evidence special features and to explain unusual behaviors. This brings new physical understanding on the undergoing physical mechanisms and suggests new ways to engineer the Casimir effect.

  16. Influence of anatomic location of lidocaine patch 5% on effectiveness and tolerability for postherpetic neuralgia

    Directory of Open Access Journals (Sweden)

    Nalamachu S

    2013-06-01

    Full Text Available Srinivas Nalamachu,1 Matthew Wieman,2 Leah Bednarek,2 Surya Chitra21International Clinical Research Institute, Overland Park, KS, 2Endo Pharmaceuticals Inc, Malvern, PA, USAPurpose: Lidocaine patch 5% is recommended as a first-line therapy for postherpetic neuralgia pain in neuropathic pain guidelines. Postherpetic neuralgia can occur anywhere on the body but often follows acute herpes zoster occurring in trigeminal and brachial plexus dermatomes. An analysis was conducted to determine whether the anatomic location of lidocaine patch 5% is associated with variations in effectiveness or tolerability in patients with postherpetic neuralgia.Methods: This was a post hoc analysis by anatomic site of patch placement (head [including neck], trunk [chest, abdomen, back, hips], and extremities [arm, leg] of a 4-week, multicenter, open-label study that enrolled patients with persistent pain following herpes zoster infection. Effectiveness was measured by Brief Pain Inventory (BPI average pain intensity (0 [no pain] to 10 [worst imaginable pain] and the BPI subscale for pain relief (0% [no relief] to 100% [complete relief]. Tolerability was assessed on the basis of patient-reported adverse events.Results: Of 332 enrolled patients (59.6% women [n = 198]; 92.5% white [n = 307]; mean [standard deviation] age, 71.2 [13.9] years, those (n = 203 who applied lidocaine patch 5% to a single anatomic site only and had baseline and postbaseline pain score data were analyzed (trunk, n = 130; head, n = 41; extremities, n = 32. The frequency of adverse events differed significantly by anatomic location, with significantly more adverse events reported with patch placement on the head versus the extremities (P = 0.006 or trunk (P = 0.02. BPI average pain improved significantly from baseline in each of the three anatomic areas (mean score decrease, 1.50–2.04; P ≤ 0.002, with no significant difference in effectiveness by patch location.Conclusion: Lidocaine 5% patch was

  17. Internal Occipital Crest Misalignment with Internal Occipital Protuberance: A Case Report of Posterior Cranial Fossa Anatomic Variations

    Directory of Open Access Journals (Sweden)

    Jae Ha Kim

    2016-01-01

    Full Text Available During gross anatomy head and neck laboratory session, one dissection group observed an abnormal anatomic variation in the posterior cranial fossa of a 94-year-old male cadaver. The internal occipital crest was not aligned with internal occipital protuberance and groove for superior sagittal sinus. It seemed that the internal occipital protuberance was shifted significantly to the right side. As a result the skull was overly stretched in order to connect with the internal occipital ridge. These internal skull variations of occipital bone landmarks can influence the location of adjacent dural venous sinuses and possibly influence cerebrospinal fluid flow. Similar anatomical anomalies have been attributed to presence of hydrocephalus and abnormalities in cisterna magna.

  18. ANATOMIC STUDY OF THE PROXIMAL THIRD OF THE FEMUR: FEMOROACETABULAR IMPACT AND THE CAM EFFECT

    OpenAIRE

    Labronici, Pedro José; Alves, Sergio Delmonte; da Silva, Anselmo Fernandes; Giuberti, Gilberto Ribeiro; de Azevedo Neto, Justino Nóbrega; Mezzalira Penedo, Jorge Luiz

    2015-01-01

    To analyze anatomical variations of the proximal end of femur that could cause a femoroacetabular impact. Methods: 199 skeletically mature anatomical specimens of femurs were used. The femurs were measured in order to determine the anteversion angle of the femoral neck, neckshaft angle, sphericity of the femoral head at anteroposterior and superoinferior, angle between epiphysis and the anterior femoral neck, angle between epiphysis and the neck at lateral plane, anteroposterior distance at 5...

  19. Effect of anatomical backgrounds on detectability in volumetric cone beam CT images

    Science.gov (United States)

    Han, Minah; Park, Subok; Baek, Jongduk

    2016-03-01

    As anatomical noise is often a dominating factor affecting signal detection in medical imaging, we investigate the effects of anatomical backgrounds on signal detection in volumetric cone beam CT images. Signal detection performances are compared between transverse and longitudinal planes with either uniform or anatomical backgrounds. Sphere objects with diameters of 1mm, 5mm, 8mm, and 11mm are used as the signals. Three-dimensional (3D) anatomical backgrounds are generated using an anatomical noise power spectrum, 1/fβ, with β=3, equivalent to mammographic background [1]. The mean voxel value of the 3D anatomical backgrounds is used as an attenuation coefficient of the uniform background. Noisy projection data are acquired by the forward projection of the uniform and anatomical 3D backgrounds with/without sphere lesions and by the addition of quantum noise. Then, images are reconstructed by an FDK algorithm [2]. For each signal size, signal detection performances in transverse and longitudinal planes are measured by calculating the task SNR of a channelized Hotelling observer with Laguerre-Gauss channels. In the uniform background case, transverse planes yield higher task SNR values for all sphere diameters but 1mm. In the anatomical background case, longitudinal planes yield higher task SNR values for all signal diameters. The results indicate that it is beneficial to use longitudinal planes to detect spherical signals in anatomical backgrounds.

  20. Rare anatomical variations of persistent trigeminal artery in two patients with non-aneurysmal subarachnoid hemorrhage.

    Science.gov (United States)

    Samaniego, Edgar A; Dabus, Guilherme; Andreone, Vincenzo; Linfante, Italo

    2011-09-01

    Carotid-basilar anastomoses are remnants of the fetal circulation and although rare, they may become symptomatic and should be recognized during cerebral angiography. Two patients are described with non-aneurysmal subarachnoid hemorrhage and persistent trigeminal arteries (PTA) found on cerebral angiography. In the first patient, the PTA ended in the anterior inferior cerebellar artery (AICA) and posterior inferior cerebellar artery. The second patient had a PTA terminating in the AICA and superior cerebellar artery. These rare anatomical PTA variants should be recognized on cerebral angiography. PMID:21990842

  1. Individual differences in distinct components of attention are linked to anatomical variations in distinct white matter tracts

    Directory of Open Access Journals (Sweden)

    Sumit N Niogi

    2010-02-01

    Full Text Available Inter-subject variations in white matter tract properties are known to correlate with individual differences in cognitive performance in domains such as attention, yet the specificity of such linkages is unknown, both at level of specific component operations and their association with anatomically distinct networks. This study examines individual performance variation within three specific functional components of attention-- alterting, orienting, and conflict processing – identified by the Attention Network Task (ANT, and relates each to inter-subject variation in a distinct set of white matter tract regions. Diffusion tensor imaging (DTI data collected via 55 diffusion-encoding directions in a 3 Tesla MRI scan, and average fractional anisotropy (FA was assessed within a set of individualized, a priori defined regions of interest, via the Reliable Objective Quantification Scheme (ROQS (Niogi & McCandliss, 2006, Niogi et al., 2007. Results demonstrate three functionally distinct components of attention that each correlate specifically and distinctly with three white matter tract regions. Structure-function correlations were found between alerting and the posterior limb of the internal capsule (PLIC, orienting and the splenium of the corpus callosum, and, conflict and the anterior corona radiata (ACR. A multiple regression/dissociation analysis demonstrated a triple dissociation between these three structure-function relationships, providing evidence of three functional and anatomically separable networks. These results extend previous findings from functional imaging and lesion studies that suggest these three components of attention are sub-served by dissociable networks, and suggest that variations in white matter tract microstructure may modulate the efficacy of these cognitive processes in highly specific ways.

  2. Anatomical variations of trabecular bone structure in intraoral radiographs using fractal and particles count analyses

    International Nuclear Information System (INIS)

    This study was performed to evaluate possible variations in maxillary and mandibular bone texture of normal population using the fractal analysis, particles count, and area fraction in intraoral radiographs. Periapical radiographs of patients who had full mouth intraoral radiographs were collected. Regions of interest (100X100 pixels) were located between the teeth of the maxillary anterior, premolar, and molar area, as well as the mandibular anterior, premolar, and molar areas. The fractal dimension (FD) was calculated by using the box counting method. The particle count (PC) and area fraction (AF) analyses were also performed. There was no significant difference in the FD values among the different groups of age, gender, upper, and lower jaws. The mean FD value was 1.49±0.01. The mean PC ranged from 44 to 54, and the mean AF ranged from 10.92 to 11.85. The values of FD, PC, and AF were significantly correlated with each other except for the upper molar area. According to the results, patients with normal trabecular pattern showed a FD of approximately 1.5. Based on these results, further investigation would be recommended if the FD value of patient significantly different from this number, since the alteration of this value indicates microstructural modification of trabecular pattern of the jaws. Additionally, with periapical radiographs, simple and cost-effective, PC and AF could be used to assess the deviation from the normal.

  3. Anatomical variations of trabecular bone structure in intraoral radiographs using fractal and particles count analyses

    Energy Technology Data Exchange (ETDEWEB)

    Amer, Maha Eshak [Faculty of Dentistry, Minia University, El Menia (Egypt); Heo, Min Suk [School of Dentistry, Seoul National University, Seoul (Korea, Republic of); Brooks, Sharon L; Benavides, Erika [School of Dentistry, University of Michigan, Ann Arbor (United States)

    2012-03-15

    This study was performed to evaluate possible variations in maxillary and mandibular bone texture of normal population using the fractal analysis, particles count, and area fraction in intraoral radiographs. Periapical radiographs of patients who had full mouth intraoral radiographs were collected. Regions of interest (100X100 pixels) were located between the teeth of the maxillary anterior, premolar, and molar area, as well as the mandibular anterior, premolar, and molar areas. The fractal dimension (FD) was calculated by using the box counting method. The particle count (PC) and area fraction (AF) analyses were also performed. There was no significant difference in the FD values among the different groups of age, gender, upper, and lower jaws. The mean FD value was 1.49{+-}0.01. The mean PC ranged from 44 to 54, and the mean AF ranged from 10.92 to 11.85. The values of FD, PC, and AF were significantly correlated with each other except for the upper molar area. According to the results, patients with normal trabecular pattern showed a FD of approximately 1.5. Based on these results, further investigation would be recommended if the FD value of patient significantly different from this number, since the alteration of this value indicates microstructural modification of trabecular pattern of the jaws. Additionally, with periapical radiographs, simple and cost-effective, PC and AF could be used to assess the deviation from the normal.

  4. SEM characterization of anatomical variation in chitin organization in insect and arthropod cuticles.

    Science.gov (United States)

    Chandran, Rakkiyappan; Williams, Lee; Hung, Albert; Nowlin, Kyle; LaJeunesse, Dennis

    2016-03-01

    The cuticles of insects and arthropods have some of the most diverse material properties observed in nature, so much so that it is difficult to imagine that all cutciles are primarily composed of the same two materials: a fibrous chitin network and a matrix composed of cuticle proteins. Various factors contribute to the mechanical and optical properties of an insect or arthropod cuticle including the thickness and composition. In this paper, we also identified another factor that may contribute to the optical, surface, and mechanical properties of a cuticle, i.e. the organization of chitin nanofibers and chitin fiber bundles. Self-assembled chitin nanofibers serve as the foundation for all higher order chitin structures in the cuticles of insects and other arthropods via interactions with structural cuticle proteins. Using a technique that enables the characterization of chitin organization in the cuticle of intact insects and arthropod exoskeletons, we demonstrate a structure/function correlation of chitin organization with larger scale anatomical structures. The chitin scaffolds in cuticles display an extraordinarily diverse set of morphologies that may reflect specific mechanical or physical properties. After removal of the proteinaceous and mineral matrix of a cuticle, we observe using SEM diverse nanoscale and micro scale organization of in-situ chitin in the wing, head, eye, leg, and dorsal and ventral thoracic regions of the periodical cicada Magicicada septendecim and in other insects and arthropods. The organization of chitin also appears to have a significant role in the organization of nanoscale surface structures. While microscale bristles and hairs have long been known to be chitin based materials formed as cellular extensions, we have found a nanostructured layer of chitin in the cuticle of the wing of the dog day annual cicada Tibicen tibicens, which may be the scaffold for the nanocone arrays found on the wing. We also use this process to examine

  5. SEM characterization of anatomical variation in chitin organization in insect and arthropod cuticles.

    Science.gov (United States)

    Chandran, Rakkiyappan; Williams, Lee; Hung, Albert; Nowlin, Kyle; LaJeunesse, Dennis

    2016-03-01

    The cuticles of insects and arthropods have some of the most diverse material properties observed in nature, so much so that it is difficult to imagine that all cutciles are primarily composed of the same two materials: a fibrous chitin network and a matrix composed of cuticle proteins. Various factors contribute to the mechanical and optical properties of an insect or arthropod cuticle including the thickness and composition. In this paper, we also identified another factor that may contribute to the optical, surface, and mechanical properties of a cuticle, i.e. the organization of chitin nanofibers and chitin fiber bundles. Self-assembled chitin nanofibers serve as the foundation for all higher order chitin structures in the cuticles of insects and other arthropods via interactions with structural cuticle proteins. Using a technique that enables the characterization of chitin organization in the cuticle of intact insects and arthropod exoskeletons, we demonstrate a structure/function correlation of chitin organization with larger scale anatomical structures. The chitin scaffolds in cuticles display an extraordinarily diverse set of morphologies that may reflect specific mechanical or physical properties. After removal of the proteinaceous and mineral matrix of a cuticle, we observe using SEM diverse nanoscale and micro scale organization of in-situ chitin in the wing, head, eye, leg, and dorsal and ventral thoracic regions of the periodical cicada Magicicada septendecim and in other insects and arthropods. The organization of chitin also appears to have a significant role in the organization of nanoscale surface structures. While microscale bristles and hairs have long been known to be chitin based materials formed as cellular extensions, we have found a nanostructured layer of chitin in the cuticle of the wing of the dog day annual cicada Tibicen tibicens, which may be the scaffold for the nanocone arrays found on the wing. We also use this process to examine

  6. Intraspecific Variation in Wood Anatomical, Hydraulic, and Foliar Traits in Ten European Beech Provenances Differing in Growth Yield

    Science.gov (United States)

    Hajek, Peter; Kurjak, Daniel; von Wühlisch, Georg; Delzon, Sylvain; Schuldt, Bernhard

    2016-01-01

    In angiosperms, many studies have described the inter-specific variability of hydraulic-related traits and little is known at the intra-specific level. This information is however mandatory to assess the adaptive capacities of tree populations in the context of increasing drought frequency and severity. Ten 20-year old European beech (Fagus sylvatica L.) provenances representing the entire distribution range throughout Europe and differing significantly in aboveground biomass increment (ABI) by a factor of up to four were investigated for branch wood anatomical, hydraulic, and foliar traits in a provenance trial located in Northern Europe. We quantified to which extend xylem hydraulic and leaf traits are under genetic control and tested whether the xylem hydraulic properties (hydraulic efficiency and safety) trades off with yield and wood anatomical and leaf traits. Our results showed that only three out of 22 investigated ecophysiological traits showed significant genetic differentiations between provenances, namely vessel density (VD), the xylem pressure causing 88% loss of hydraulic conductance and mean leaf size. Depending of the ecophysiological traits measured, genetic differentiation between populations explained 0–14% of total phenotypic variation, while intra-population variability was higher than inter-population variability. Most wood anatomical traits and some foliar traits were additionally related to the climate of provenance origin. The lumen to sapwood area ratio, vessel diameter, theoretical specific conductivity and theoretical leaf-specific conductivity as well as the C:N-ratio increased with climatic aridity at the place of origin while the carbon isotope signature (δ13C) decreased. Contrary to our assumption, none of the wood anatomical traits were related to embolism resistance but were strong determinants of hydraulic efficiency. Although ABI was associated with both VD and δ13C, both hydraulic efficiency and embolism resistance were

  7. Intraspecific Variation in Wood Anatomical, Hydraulic, and Foliar Traits in Ten European Beech Provenances Differing in Growth Yield.

    Science.gov (United States)

    Hajek, Peter; Kurjak, Daniel; von Wühlisch, Georg; Delzon, Sylvain; Schuldt, Bernhard

    2016-01-01

    In angiosperms, many studies have described the inter-specific variability of hydraulic-related traits and little is known at the intra-specific level. This information is however mandatory to assess the adaptive capacities of tree populations in the context of increasing drought frequency and severity. Ten 20-year old European beech (Fagus sylvatica L.) provenances representing the entire distribution range throughout Europe and differing significantly in aboveground biomass increment (ABI) by a factor of up to four were investigated for branch wood anatomical, hydraulic, and foliar traits in a provenance trial located in Northern Europe. We quantified to which extend xylem hydraulic and leaf traits are under genetic control and tested whether the xylem hydraulic properties (hydraulic efficiency and safety) trades off with yield and wood anatomical and leaf traits. Our results showed that only three out of 22 investigated ecophysiological traits showed significant genetic differentiations between provenances, namely vessel density (VD), the xylem pressure causing 88% loss of hydraulic conductance and mean leaf size. Depending of the ecophysiological traits measured, genetic differentiation between populations explained 0-14% of total phenotypic variation, while intra-population variability was higher than inter-population variability. Most wood anatomical traits and some foliar traits were additionally related to the climate of provenance origin. The lumen to sapwood area ratio, vessel diameter, theoretical specific conductivity and theoretical leaf-specific conductivity as well as the C:N-ratio increased with climatic aridity at the place of origin while the carbon isotope signature (δ(13)C) decreased. Contrary to our assumption, none of the wood anatomical traits were related to embolism resistance but were strong determinants of hydraulic efficiency. Although ABI was associated with both VD and δ(13)C, both hydraulic efficiency and embolism resistance were

  8. Intraspecific Variation in Wood Anatomical, Hydraulic, and Foliar Traits in Ten European Beech Provenances Differing in Growth Yield.

    Science.gov (United States)

    Hajek, Peter; Kurjak, Daniel; von Wühlisch, Georg; Delzon, Sylvain; Schuldt, Bernhard

    2016-01-01

    In angiosperms, many studies have described the inter-specific variability of hydraulic-related traits and little is known at the intra-specific level. This information is however mandatory to assess the adaptive capacities of tree populations in the context of increasing drought frequency and severity. Ten 20-year old European beech (Fagus sylvatica L.) provenances representing the entire distribution range throughout Europe and differing significantly in aboveground biomass increment (ABI) by a factor of up to four were investigated for branch wood anatomical, hydraulic, and foliar traits in a provenance trial located in Northern Europe. We quantified to which extend xylem hydraulic and leaf traits are under genetic control and tested whether the xylem hydraulic properties (hydraulic efficiency and safety) trades off with yield and wood anatomical and leaf traits. Our results showed that only three out of 22 investigated ecophysiological traits showed significant genetic differentiations between provenances, namely vessel density (VD), the xylem pressure causing 88% loss of hydraulic conductance and mean leaf size. Depending of the ecophysiological traits measured, genetic differentiation between populations explained 0-14% of total phenotypic variation, while intra-population variability was higher than inter-population variability. Most wood anatomical traits and some foliar traits were additionally related to the climate of provenance origin. The lumen to sapwood area ratio, vessel diameter, theoretical specific conductivity and theoretical leaf-specific conductivity as well as the C:N-ratio increased with climatic aridity at the place of origin while the carbon isotope signature (δ(13)C) decreased. Contrary to our assumption, none of the wood anatomical traits were related to embolism resistance but were strong determinants of hydraulic efficiency. Although ABI was associated with both VD and δ(13)C, both hydraulic efficiency and embolism resistance were

  9. Anatomical variations of the celiac trunk and hepatic arterial system: an analysis using multidetector computed tomography angiography

    Energy Technology Data Exchange (ETDEWEB)

    Araujo Neto, Severino Aires; Franca, Henrique Almeida; Mello Junior, Carlos Fernando de; Silva Neto, Eulampio Jose; Negromonte, Gustavo Ramalho Pessoa; Duarte, Claudia Martina Araujo; Cavalcanti Neto, Bartolomeu Fragoso; Farias, Rebeca Danielly da Fonseca, E-mail: severinoaires@hotmail.com [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil)

    2015-11-15

    Objective: To analyze the prevalence of anatomical variations of celiac arterial trunk (CAT) branches and hepatic arterial system (HAS), as well as the CAT diameter, length and distance to the superior mesenteric artery. Materials And Methods: Retrospective, cross-sectional and predominantly descriptive study based on the analysis of multidetector computed tomography images of 60 patients. Results: The celiac trunk anatomy was normal in 90% of cases. Hepatosplenic trunk was found in 8.3% of patients, and hepatogastric trunk in 1.7%. Variation of the HAS was observed in 21.7% of cases, including anomalous location of the right hepatic artery in 8.3% of cases, and of the left hepatic artery, in 5%. Also, cases of joint relocation of right and left hepatic arteries, and trifurcation of the proper hepatic artery were observed, respectively, in 3 (5%) and 2 (3.3%) patients. Mean length and caliber of the CAT were 2.3 cm and 0.8 cm, respectively. Mean distance between CAT and superior mesenteric artery was 1.2 cm (standard deviation = 4.08). A significant correlation was observed between CAT diameter and length, and CAT diameter and distance to superior mesenteric artery. Conclusion: The pattern of CAT variations and diameter corroborate the majority of the literature data. However, this does not happen in relation to the HAS. (author)

  10. Anatomical variations of the celiac trunk and hepatic arterial system: an analysis using multidetector computed tomography angiography

    International Nuclear Information System (INIS)

    Objective: To analyze the prevalence of anatomical variations of celiac arterial trunk (CAT) branches and hepatic arterial system (HAS), as well as the CAT diameter, length and distance to the superior mesenteric artery. Materials And Methods: Retrospective, cross-sectional and predominantly descriptive study based on the analysis of multidetector computed tomography images of 60 patients. Results: The celiac trunk anatomy was normal in 90% of cases. Hepatosplenic trunk was found in 8.3% of patients, and hepatogastric trunk in 1.7%. Variation of the HAS was observed in 21.7% of cases, including anomalous location of the right hepatic artery in 8.3% of cases, and of the left hepatic artery, in 5%. Also, cases of joint relocation of right and left hepatic arteries, and trifurcation of the proper hepatic artery were observed, respectively, in 3 (5%) and 2 (3.3%) patients. Mean length and caliber of the CAT were 2.3 cm and 0.8 cm, respectively. Mean distance between CAT and superior mesenteric artery was 1.2 cm (standard deviation = 4.08). A significant correlation was observed between CAT diameter and length, and CAT diameter and distance to superior mesenteric artery. Conclusion: The pattern of CAT variations and diameter corroborate the majority of the literature data. However, this does not happen in relation to the HAS. (author)

  11. Assessment and Evaluation of Anatomic Variations of Retromolar Pad: A Cross Sectional Study

    Science.gov (United States)

    Deep, Anchal; Siwach, Amit; Singh, Manas; Bhargava, Akshay; Siwach, Reenu

    2016-01-01

    Introduction The retromolar pad also called piriformis papilla is a mucosal elevation located in the retromolar area covering the retromolar triangle. After molar loss, the bony alveolar process and surrounding soft periodontal tissue remodel, mainly resorb and blend with retromolar pad. It is a key intraoral landmark in prosthodontics. Aim The aim of this in-vitro study was to analyze the various anatomical shapes and sizes of retromolar pad in 150 completely edentulous patients between 55 to 70 years of age group. Materials and Methods The study was conducted on 150 completely edentulous patients. The shapes of retromolar pad on the left and right side were seen and divided into pear, triangular and round shape. The comparison of the mean longitudinal diameter and transverse diameter on the right and left sides was done. The data was evaluated statistically. The chi-square test was used for the comparison between the proportions with the help of standard deviation, t-test was used for comparison between the left and the right side and ANOVA test was used for comparison between the various shapes of the retromolar pads. Results The result showed that there was statistically significant difference among different shapes of retromolar pad and there was significant difference in mean transverse and longitudinal diameter on right and left side, the mean value of the longitudinal diameter on left and right side was 8.81 and 8.69 whereas the mean value of the transverse diameter on left and right side was 6.79 and 6.82 respectively and p-value obtained for both was 0.550 and 0.814 respectively. Conclusion The study conclude that there are three different shapes of retromolar pad among which pear and triangular shaped retomolar pad provides more stability in lower denture because of increase surface area. PMID:27437350

  12. Anatomical variation of the flexor digitorum brevis muscle revisited: a case report from South Indian population

    Directory of Open Access Journals (Sweden)

    Thangarajan R

    2010-12-01

    Full Text Available We observed a variation in the flexor digitorum brevis muscle of a 50-year-old female cadaver in our routine dissection. In the sole of right foot, we found that flexor digitorum brevis was giving only three tendons for middle three toes. The tendon of flexor digitorum brevis for the little toe was missing. The absent 4th tendon of the flexor digitorum brevis to little toe in the right foot was replaced by an isolated flexor muscle arising from the medial margin of the tendinous plate of the flexor digitorum brevis. The tendon of isolated flexor muscles inserted in to base of distal phalanx of the little toe. Variation of the flexor digitorum brevis may be important to plastic surgeons because of reconstruction of the heel pad by flexor digitorum brevis musculocutaneous flap transfer.

  13. Effects of Anatomical Characteristics of Ethiopian Lowland Bamboo on Physical and Mechanical Properties

    Institute of Scientific and Technical Information of China (English)

    SEYOUM; Kelemwork

    2009-01-01

    The main aim of this study was to evaluate the effects of anatomical characteristics of Ethiopian lowland bamboo on selected physical and mechanical properties. A total of 45 solid culms from three different age groups (2-, 3- and 4- year-old) were harvested from natural bamboo forest in Ethiopia and then samples were transported to China for carrying out anatomical characteristics test. Physical and mechanical properties testing were conducted in Ethiopia. The result indicates that age and height had signi...

  14. Rare anatomic variation of left gastric artery and right hepatic artery in a female cadaver.

    Science.gov (United States)

    Troupis, Theodore; Chatzikokolis, Stamatis; Zachariadis, Michael; Troupis, George; Anagnostopoulou, Sofia; Skandalakis, Panayiotis

    2008-05-01

    The present report describes a rare case in which the left gastric artery arises directly from the abdominal aorta and the right hepatic artery from the superior mesenteric artery, as observed during the dissection of a female cadaver. The left gastric artery usually rises as one of the three branches of the celiac trunk, which was originally described by Haller in 1756, whereas the right hepatic artery usually originates from the proper hepatic artery. The knowledge of the typical anatomy of the abdominal arteries, and their variations, is especially important due to the numerous interventions performed in the abdominal area.

  15. Axial variations in anatomical properties and basic density of Eucalypt urograndis hybrid (Eucalyptus grandis 3 E. urophylla) clones

    Institute of Scientific and Technical Information of China (English)

    S K Sharma; S R Shukla; S Shashikala; V Sri Poornima

    2015-01-01

    We studied two clones of Eucalypt urograndis hybrid (Eucalyptus grandis 9 E. urophylla), GR283 and GR330, grown in Tumkur district of Karnataka (India), and felled 5–6 years old three trees of each clone. We recorded axial variations in heartwood content, bark properties, wood density and anatomical characteristics of wood including fibre length, fibre diameter, fibre wall thickness, lumen diameter, vessel frequency, vessel diameter and vessel element length. Clone GR283 had about 10 % heartwood, significantly lower than for clone GR330 (37 %). Basic wood density along the tree height varied significantly within and between the clones. We observed significant variations in fibre length, fibre diameter and wall thickness within and between the two clones. Vessel frequency and vessel element length did not vary but vessel diameter differed significantly between the clones. With a greater proportion of sapwood, clone GR283 can be utilized for paper and pulp applications. Clone GR330 had a higher proportion of heartwood and lower wood density and, hence, is more suitable for light-weight material applications.

  16. Fusiform aneurysm of a persistent primitive trigeminal artery associated with cerebrovascular anatomic variations: a report of two cases.

    Science.gov (United States)

    Pleş, Horia; Loukas, Marios; Andall, Rebecca G; Andall, Naomi R; Iacob, Nicoleta; Miclăuş, GraŢian Dragoslav; Matusz, Petru; Tubbs, R Shane

    2015-01-01

    There are four embryonic anastomoses that exist between the internal carotid artery (ICA) and the vertebrobasilar (VB) system, which may fail to regress postfetal life; one of which is the trigeminal artery. Other persistent anastomoses include those formed by the hypoglossal, otic and proatlantic intersegmental arteries. In addition, other cerebrovascular variations may accompany a persistent primitive trigeminal artery (PPTA); such as arteriovenous malformations, aneurysms, carotid-cavernous fistulas and stenotic cerebral vessels. We present two very rare cases of a left PPTA. In the first case, there was a past medical history significant for cervico-thoraco-lumbar spondylitis and in the second case of an operated occipital astrocytoma. In both cases, the PPTA was associated with a fusiform aneurysm located in the carotidian (lateral) aspect of the PPTA as well as other cerebrovascular anatomic variations. In the first case, the length of the PPTA was 26.0 mm and its endoluminal diameter, at its origin at the ICA, was 1.8 mm; the aneurysm has a length of 8.4 mm. In the second case, the length of the PPTA was 31.0 mm and its endoluminal diameter at its origin at the ICA was 3.0 mm; the aneurysm have a length of 7.6 mm. Identification of these variant vessels should not be ignored before planning and execution of neurosurgeries to prevent possible perioperative risks. PMID:26662153

  17. Prevalence of anatomical variations of cystic artery in South Indian cadavers

    Directory of Open Access Journals (Sweden)

    Tejaswi HL

    2013-08-01

    Full Text Available Background: The knowledge of variations in the origin and course of cystic artery is important for the surgeons as uncontrolled bleeding from the cystic artery and its branches can be fatal during cholecystectomy. Intra operative bleeding can result in an increase in the risk of intra operative injury to vital vascular and biliary structures. Keeping in view the clinical significance and applied importance of the cystic artery anatomy and to add some more knowledge to the existing ones, the present study was undertaken, to know in detail the level of origin, length, and variations in the course and relation of the cystic artery. Methods: The present study was performed on 100 human liver specimens with intact gallbladder and extrahepatic duct system, obtained after dissection from the cadavers in the Department of Anatomy and from post-mortem cases from the Department of Forensic Medicine, Mysore Medical College and Research Institute, Mysore, over a period of 18 months. Results: Most common source of origin of the cystic artery was the right hepatic artery in 92 cases (92% followed by aberrant right hepatic artery in 4 cases (4% and the least common sources observed were the left hepatic artery in 1 case (1% and the gastroduodenal artery in 1 case (1%.Mean length of the cystic artery was 17.6 mm and ranged between 3.7 mm to 42 mm. Out of the 100 dissected specimens, in 65 (65% the cystic artery was found inside the Calot’s triangle and in 35 (35% outside the triangle. Conclusion: This study provides details of the normal as well as the variant anatomy of the cystic artery, knowledge of which is very essential for the surgeons to minimize the risk of injury to the blood vessels and the biliary apparatus during cholecystectomy. [Int J Res Med Sci 2013; 1(4.000: 424-428

  18. [Measures to anatomic variations of the colonic vessels in laparoscopic operations].

    Science.gov (United States)

    Pan, Kai

    2013-10-01

    In laparoscopic colorectal resection, the poor blood supply of the anastomosis after tumor excision is difficult to be determined during the operations sometimes. The change in blood supply of the bowel is mainly due to the mesenteric anatomy and the operative techniques. The direct blood supply of colon is the marginal vessels in the mesentery. The integrity and patency of the marginal vessels determine the vitality of the bowel. However, the marginal vessels are different in diameter, pulsation or even discontinue in various areas, affecting the excision of the colon and following anastomosis. The most common three dangerous areas to anastomosis include:(1)area between ileocolic artery and right colonic artery; (2)area between middle colonic artery and left colonic artery-the Griffiths point. (3)area between the terminal branch of sigmoid colonic artery and superior rectal artery-Sudeck dangerous area. In laparoscopic colorectal resection, one should pay attention to protect the blood supply of the bowel and the marginal blood vessels, and be vigilant to the three vascular variations above mentioned. The vessels should be ligated accurately to ensure sufficient blood supply to the anastomosis and consequent normal healing of the rectal and colonic anastomosis. More attention should be paid to the elderly, morbid, and diabetic patients. If the safety of the anastomosis is unsure, prophylactic ileostomy should be performed. PMID:24158864

  19. LEAF ANATOMICAL VARIATION IN RELATION TO STRESS TOLERANCE AMONG SOME WOODY SPECIES ON THE ACCRA PLAINS OF GHANA

    OpenAIRE

    DZOMEKU BELOVED MENSAH

    2012-01-01

    Leaf anatomical study was conducted on some woody species on the Accra Plains of Ghana. Leaf epidermal strips and transverse sections were mounted in Canada balsam and studied. The anatomical studies revealed numerous stomata on the lower epidermis of Azadirachta indica. The anatomical studies revealed the presence of thick cuticles, double-layered palisade mesophyll in most species and the presence of epidermal hairs in some species. Ficus capensis showed the presence of cystolith in the low...

  20. Anatomic variation of the deep venous system and its relationship with deep vein thrombosis found on the lower extremity venograms that were obtained after artificial joint replacements

    International Nuclear Information System (INIS)

    We wanted to evaluate the anatomic variations, the number of valves and the presence of deep vein thrombosis (DVT) on the lower extremity venograms obtained after artificial joint replacements, and we also wanted to determine the correlation of the incidence of DVT with the above-mentioned factors and the operation sites. From January to June 2004, conventional ascending contrast venographies of the lower extremities were performed in 119 patients at 7-10 days after artificial joint replacement, and all the patients were asymptomatic. Total knee replacement was done for 152 cases and total hip replacement was done for 34 cases. On all the venographic images of 186 limbs, the anatomic variations were classified and the presence of DVT was evaluated; the number of valves in the superficial femoral vein (SFV) and calf veins was counted. The sites of DVT were classified as calf, thigh and pelvis. Statistically, chi square tests and Fischer's exact tests were performed to determine the correlation of the incidence of DVT with the anatomic variations, the numbers of valves and the operation sites. Theoretically, there are 9 types of anatomical variation in the deep vein system of the lower extremity that can be classified, but only 7 types were observed in this study. The most frequent type was the normal single SFV type and this was noted in 117 cases (63%), and the others were all variations (69 cases, 37%). There was a 22.2% incidence of DVT (69 cases) in the normal single SFV type and 26.4% (17 cases) in the other variations. No significant difference was noted in the incidences of DVT between the two groups. In addition, no significant statistical differences were noted for the incidences of DVT between the single or variant multiple veins in the SFV and the popliteal vein (PV) respectively, between the different groups with small or large numbers of valves in the thigh and calf, respectively, and also between the different operation sites of the hip or knee

  1. Anatomic variation of the deep venous system and its relationship with deep vein thrombosis found on the lower extremity venograms that were obtained after artificial joint replacements

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Min Sun; Lee, Jee Eun; Hwang, Ji Young; Shim, Sung Shine; Yoo, Jeong Hyun; Suh, Jeong Soo; Park, Jae Young [College of Medicine, Ewha Womans University, Seoul (Korea, Republic of)

    2006-11-15

    We wanted to evaluate the anatomic variations, the number of valves and the presence of deep vein thrombosis (DVT) on the lower extremity venograms obtained after artificial joint replacements, and we also wanted to determine the correlation of the incidence of DVT with the above-mentioned factors and the operation sites. From January to June 2004, conventional ascending contrast venographies of the lower extremities were performed in 119 patients at 7-10 days after artificial joint replacement, and all the patients were asymptomatic. Total knee replacement was done for 152 cases and total hip replacement was done for 34 cases. On all the venographic images of 186 limbs, the anatomic variations were classified and the presence of DVT was evaluated; the number of valves in the superficial femoral vein (SFV) and calf veins was counted. The sites of DVT were classified as calf, thigh and pelvis. Statistically, chi square tests and Fischer's exact tests were performed to determine the correlation of the incidence of DVT with the anatomic variations, the numbers of valves and the operation sites. Theoretically, there are 9 types of anatomical variation in the deep vein system of the lower extremity that can be classified, but only 7 types were observed in this study. The most frequent type was the normal single SFV type and this was noted in 117 cases (63%), and the others were all variations (69 cases, 37%). There was a 22.2% incidence of DVT (69 cases) in the normal single SFV type and 26.4% (17 cases) in the other variations. No significant difference was noted in the incidences of DVT between the two groups. In addition, no significant statistical differences were noted for the incidences of DVT between the single or variant multiple veins in the SFV and the popliteal vein (PV) respectively, between the different groups with small or large numbers of valves in the thigh and calf, respectively, and also between the different operation sites of the hip or knee

  2. Study on the effect of stump height and number of coppice shoots per stump on some anatomical properties of Eucalyptus camaldulensis Dehn. wood growth in Nineveh plantation

    Energy Technology Data Exchange (ETDEWEB)

    Kasir, W.A.; Barno, J.S.

    1985-01-01

    Fiber length, diameter, wall thickness, the ratio of fiber length to diameter, and vessel element length and diameter were recorded from wood samples collected in an irrigated stand. Stump height significantly affected all anatomical features recorded except fiber wall thickness. The number of coppice shoots had significant effects on all features except vessel diameter. Anatomical variation was greater in the radial direction than along the stem axis. The use of wood from low stumps with 4 shoots is recommended, although wood produced under all conditions studied can be useful for some products. 18 references.

  3. Anatomically guided voxel-based partial volume effect correction in brain PET : Impact of MRI segmentation

    NARCIS (Netherlands)

    Gutierrez, Daniel; Montandon, Marie-Louise; Assal, Frederic; Allaoua, Mohamed; Ratib, Osman; Loevblad, Karl-Olof; Zaidi, Habib

    2012-01-01

    Partial volume effect is still considered one of the main limitations in brain PET imaging given the limited spatial resolution of current generation PET scanners. The accuracy of anatomically guided partial volume effect correction (PVC) algorithms in brain PET is largely dependent on the performan

  4. Evaluation of the dosimetric impact of interfractional anatomical variations on prostate proton therapy using daily in-room CT images

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yi; Efstathiou, Jason A.; Sharp, Gregory C.; Lu, Hsiao-Ming; Trofimov, Alexei V. [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114 (United States); Frank Ciernik, I. [Radiation Oncology, Dessau Medical Center, Dessau 06847, Germany and Center for Clinical Research, Zurich University Hospital, Zurich 8006 (Switzerland)

    2011-08-15

    Purpose: To quantify interfractional anatomical variations and their dosimetric impact during the course of fractionated proton therapy (PT) of prostate cancer and to assess the robustness of the current treatment planning techniques. Methods: Simulation and daily in-room CT scans from ten prostate carcinoma patients were analyzed. PT treatment plans (78 Gy in 39 fractions of 2 Gy) were created on the simulation CT, delivering 25 fractions to PTV1 (expanded from prostate and seminal vesicles), followed by 14 boost fractions to PTV2 (expanded from prostate). Plans were subsequently applied to daily CT, with beams aligned to the prostate center in the sagittal plane. For five patients having a sufficiently large daily imaging volume, structure contours were manually drawn, and plans were evaluated for all CT sets. For the other five patients, the plans were evaluated for six selected fractions. The daily CT was matched to the simulation CT through deformable registration. The registration accuracy was validated for each fraction, and the three patients with a large number of accurately registered fractions were used for dose accumulation. Results: In individual fractions, the coverage of the prostate, seminal vesicles, and PTV1 was generally maintained at the corresponding prescription dose. For PTV2, the volume covered by the fractional prescription dose of 2 Gy (i.e., V2) was, on average, reduced by less than 3% compared to the simulation plan. Among the 225 (39 x 5 + 6 x 5) fractions examined, 15 showed a V2 reduction larger than 5%, of which ten were caused by a large variation in rectal gas, and five were due to a prostate shift in the craniocaudal direction. The fractional dose to the anterior rectal wall was found to increase for one patient who had large rectal gas volume in 25 of the 39 fractions, and another who experienced significant prostate volume reduction during the treatment. The fractional bladder dose generally increased with decreasing fullness

  5. Evaluation of Anatomic Variations in Maxillary Sinus with the Aid of Cone Beam Computed Tomography (CBCT in a Population in South of Iran

    Directory of Open Access Journals (Sweden)

    Shoaleh Shahidi

    2016-02-01

    Full Text Available Statement of the Problem: Anatomic variations of the maxillary sinus can be detected in cone-beam computed tomography (CBCT and may assist to locate the posterior superior alveolar artery (PSAA and define the maxillary sinus morphology more accurately for a more strict surgical treatment plan. Purpose: The study aimed to determine normal variations of the maxillary sinus with the aid of CBCT in a sample population in south of Iran. Materials and Method: This cross-sectional prevalence study was based on evaluation of 198 projection data of CBCT scans of some Iranian patients aged 18-45, referred to a private oral and maxillofacial radiology center in Shiraz from 2011 to 2013. CBCT scans were taken and analyzed with NewTom VGi device and software. The anatomic variations which were evaluated in the axial images included the presence of alveolar pneumatization, anterior pneumatization, exostosis, and hypoplasia. Moreover, the location and height of sinus septa and the location of PSAA were assessed. SPSS software (version 17.0 was used to analyze the data. Results: In a total of 396 examined sinuses, maxillary sinus alveolar pneumatization was the most common anatomic variation detected. Anterior pneumatization was detected in 96 sinuses (24.2%. Antral septa were found in 180 sinuses (45.4% and were mostly located in the anterior region. Meanwhile, PSAA was mostly detected intra-osseous in 242 sinuses (65.7%. Conclusion: Anatomic variations of the maxillary sinus were common findings in CBCT of the maxilla. Preoperative imaging with CBCT seems to be very helpful for assessing the location of PSAA and the maxillary sinus morphology; Its data might be used to adjust the surgical treatment plan to yield more successful treatments.

  6. Effectiveness of Plastinated Anatomical Specimens Depicting Common Sports Injuries to Enhance Musculoskeletal Injury Evaluation Education

    Science.gov (United States)

    Tamura, Kaori; Stickley, Christopher D.; Labrash, Steven J.; Lozanoff, Scott

    2014-01-01

    Context: Plastination techniques have emerged as effective methods for preserving human tissue and enabling human specimens to be utilized in a fashion similar to anatomical models with much greater accuracy. Opportunities to observe and experience human specimens in classroom settings should be beneficial to undergraduate and graduate students in…

  7. Effects of anatomical position on esophageal transit time: A biomagnetic diagnostic technique

    Institute of Scientific and Technical Information of China (English)

    Teodoro Cordova-Fraga; Modesto Sosa; Cados Wiechers; Jose Maria De la Roca-Chiapas; Alejandro Maldonado Moreles; Jesus BernaI-Alvarado; Raquel Huerta-Franco

    2008-01-01

    AIM: To study the esophageal transit time (ETT)and compare its mean value among three anatomical inclinations of the body; and to analyze the correlation of ETT to body mass index (BMI).METHODS: A biomagnetic technique was implemented to perform this study: (1) The transit time of a magnetic marker (MM) through the esophagus was measured using two fluxgate sensors placed over the chest of 14 healthy subjects; (2) the ETT was assessed in three anatomical positions (at upright,fowler,and supine positions; 90°,45° and 0°,respectively).RESULTS: ANOVA and Tuckey post-hoc tests demonstrated significant differences between ETT mean of the different positions.The ETT means were 5.2 ±1.1 s,6.1±1.5 s,and 23.6 ± 9.2 s for 90°,45° and 0°,respectively.Pearson correlation results were r = -0.716 and P < 0.001 by subjects' anatomical position,and r =-0.024 and P > 0.05 according the subject's BHI.CONCLUSION: We demonstrated that using this biomagnetic technique,it is possible to measure the ETT and the effects of the anatomical position on the ETT.

  8. Effects of prescribed burning on ecophysiological, anatomical and stem hydraulic properties in Pinus pinea L.

    Science.gov (United States)

    Battipaglia, Giovanna; Savi, Tadeja; Ascoli, Davide; Castagneri, Daniele; Esposito, Assunta; Mayr, Stefan; Nardini, Andrea

    2016-08-01

    Prescribed burning (PB) is a widespread management technique for wildfire hazard abatement. Understanding PB effects on tree ecophysiology is key to defining burn prescriptions aimed at reducing fire hazard in Mediterranean pine plantations, such as Pinus pinea L. stands. We assessed physiological responses of adult P. pinea trees to PB using a combination of dendroecological, anatomical, hydraulic and isotopic analyses. Tree-ring widths, xylem cell wall thickness, lumen area, hydraulic diameter and tree-ring δ(13)C and δ(18)O were measured in trees on burned and control sites. Vulnerability curves were elaborated to assess tree hydraulic efficiency or safety. Despite the relatively intense thermal treatment (the residence time of temperatures above 50 °C at the stem surface ranged between 242 and 2239 s), burned trees did not suffer mechanical damage to stems, nor significant reduction in radial growth. Moreover, the PB did not affect xylem structure and tree hydraulics. No variations in (13)C-derived water use efficiency were recorded. This confirmed the high resistance of P. pinea to surface fire at the stem base. However, burned trees showed consistently lower δ(18)O values in the PB year, as a likely consequence of reduced competition for water and nutrients due to the understory burning, which increased both photosynthetic activity and stomatal conductance. Our multi-approach analysis offers new perspectives on post-fire survival strategies of P. pinea in an environment where fires are predicted to increase in frequency and severity during the 21st century.

  9. Evaluation of the global effect of anatomical background on microcalcifications detection

    Science.gov (United States)

    Zanca, Federica; Van Ongeval, Chantal; Jacobs, Jurgen; Pöyry, Paula; Marchal, Guy; Bosmans, Hilde

    2007-03-01

    Purpose: 1/ To validate a method for simulating microcalcifications in mammography 2/ To evaluate the effect of anatomical background on visibility of (simulated) microcalcifications Materials and methods: Microcalcifications were extracted from the raw data of specimen from a stereotactic vacuum needle biopsy. The sizes of the templates varied from 200 μm to 1350μm and the peak contrast from 1.3% to 24%. Experienced breast imaging radiologists were asked to blindly evaluate images containing real and simulated lesions. Analysis was done using ROC methodology. The simulated lesions have been used for the creation of composite image datasets: 408 microcalcifications were simulated into 161 ROI's of 59 digital mammograms, having different anatomical backgrounds. Nine radiologists were asked to detect and rate them under conditions of free-search. A modified receiver operating characteristic study (FROC) was applied to find correlations between detectability and anatomical background. Results: 1/ The calculated area under the ROC curve, Az, was 0.52+/- 0.04. Simulated microcalcifications could not be distinguished from real ones. 2/ In the anatomical background classified as Category 1 (fatty), the detection fraction is the lowest (0.48), while for type 2,3,4 there is a gradually decrease (from 0.61 to 0.54) as the glandularity increases. The number of false positives is the highest for the background Category 1 (24%), compared to the other three types (16%). A 80% detectability is found for microcalcifications with a diameter > 400μm and a peak contrast >10%. Anatomic noise seems to limit detectability of large low contrast lesions, having a diameter >700μm.

  10. The pineal gland: a comparative MR imaging study in children and adults with respect to normal anatomical variations and pineal cysts

    Energy Technology Data Exchange (ETDEWEB)

    Sener, R.N. [Dept. of Radiology, Ege Univ. Hospital, Izmir (Turkey)

    1995-06-01

    This study was undertaken to evaluate the variations in appearance of the normal pineal gland. The findings of 1000 consecutive MR imaging examinations obtained at 0.5 T were studied. The age of the patients ranged from 1 day to 83 years, and findings in children and adults were compared. In all age groups the pineal gland appeared mainly in three forms: (1) nodule-like, (2) crescent-like and (3) ring-like. Overall prevalences of these forms were 52 %, 26 % and 22 %, respectively. Apparent differences in frequencies were evident in children and adults with respect to the crescent-and ring-like types. Cystiform pineal lesions 5 mm or larger in one diameter (anteroposterior, sagittal or transverse) were taken to be true pineal cysts, when compared with the gland`s ring-like appearance (less than 5 mm). Pineal cysts had a prevalence of 0.6 % in children and 2.6 % in adults. No symptomatic pineal cyst with mass effect on the lamina tecti was detected in the series. Besides identifying the three anatomical types of the pineal gland as seen on MR imaging and addressing the potential significance of differences in their frequencies in children and adults, the author tries to explain the previous discrepancy between the MR imaging and autopsy series findings with respect to frequencies of the pineal cysts. (orig.)

  11. Assessing the anatomical variations of lingual foramen and its bony canals with CBCT taken from 102 patients in Isfahan

    Directory of Open Access Journals (Sweden)

    Mahnaz Sheikhi

    2012-01-01

    Conclusion: These anatomical landmarks in Isfahan population vary from previous studies. All of the images had at least one lingual foramen which demonstrates high prevalence of this anatomy among Isfehanian population. Therefore, it is recommended to use CBCT imaging for preoperative evaluation prior to installing dental implants.

  12. LEAF ANATOMICAL VARIATION IN RELATION TO STRESS TOLERANCE AMONG SOME WOODY SPECIES ON THE ACCRA PLAINS OF GHANA

    Directory of Open Access Journals (Sweden)

    DZOMEKU BELOVED MENSAH

    2012-12-01

    Full Text Available Leaf anatomical study was conducted on some woody species on the Accra Plains of Ghana. Leaf epidermal strips and transverse sections were mounted in Canada balsam and studied. The anatomical studies revealed numerous stomata on the lower epidermis of Azadirachta indica. The anatomical studies revealed the presence of thick cuticles, double-layered palisade mesophyll in most species and the presence of epidermal hairs in some species. Ficus capensis showed the presence of cystolith in the lower epidermis whereas Zanthoxylum zanthoxyloides showed the presence of mucilage gland in the upper epidermis. Epidermal cell of Chromolaena odorata are very large with undulating cell walls. The species studied had various adaptive anatomical features. The stomatal frequency of Azadirachta indica was very high. With the exception of Chromolaena odorata the stomatal frequencies of the species were relatively high. The stomatal dimensions showed that most of the species maintained constant stomatal length during the study period except Griffonia simplicifolia that increased the stomatal width during the afternoon. Unlike Morinda lucida, Griffonia simplicifolia and Chromolaena odorata, that showed reduction in the breadth of stomata, the other species maintained constant stomatal width.

  13. Near Real-Time Assessment of Anatomic and Dosimetric Variations for Head and Neck Radiation Therapy via Graphics Processing Unit–based Dose Deformation Framework

    Energy Technology Data Exchange (ETDEWEB)

    Qi, X. Sharon, E-mail: xqi@mednet.ucla.edu [Department of Radiation Oncology, University of California Los Angeles, Los Angeles, California (United States); Santhanam, Anand; Neylon, John; Min, Yugang; Armstrong, Tess; Sheng, Ke [Department of Radiation Oncology, University of California Los Angeles, Los Angeles, California (United States); Staton, Robert J.; Pukala, Jason [Department of Radiation Oncology, UF Health Cancer Center - Orlando Health, Orlando, Florida (United States); Pham, Andrew; Low, Daniel A.; Lee, Steve P. [Department of Radiation Oncology, University of California Los Angeles, Los Angeles, California (United States); Steinberg, Michael; Manon, Rafael [Department of Radiation Oncology, UF Health Cancer Center - Orlando Health, Orlando, Florida (United States); Chen, Allen M.; Kupelian, Patrick [Department of Radiation Oncology, University of California Los Angeles, Los Angeles, California (United States)

    2015-06-01

    Purpose: The purpose of this study was to systematically monitor anatomic variations and their dosimetric consequences during intensity modulated radiation therapy (IMRT) for head and neck (H&N) cancer by using a graphics processing unit (GPU)-based deformable image registration (DIR) framework. Methods and Materials: Eleven IMRT H&N patients undergoing IMRT with daily megavoltage computed tomography (CT) and weekly kilovoltage CT (kVCT) scans were included in this analysis. Pretreatment kVCTs were automatically registered with their corresponding planning CTs through a GPU-based DIR framework. The deformation of each contoured structure in the H&N region was computed to account for nonrigid change in the patient setup. The Jacobian determinant of the planning target volumes and the surrounding critical structures were used to quantify anatomical volume changes. The actual delivered dose was calculated accounting for the organ deformation. The dose distribution uncertainties due to registration errors were estimated using a landmark-based gamma evaluation. Results: Dramatic interfractional anatomic changes were observed. During the treatment course of 6 to 7 weeks, the parotid gland volumes changed up to 34.7%, and the center-of-mass displacement of the 2 parotid glands varied in the range of 0.9 to 8.8 mm. For the primary treatment volume, the cumulative minimum and mean and equivalent uniform doses assessed by the weekly kVCTs were lower than the planned doses by up to 14.9% (P=.14), 2% (P=.39), and 7.3% (P=.05), respectively. The cumulative mean doses were significantly higher than the planned dose for the left parotid (P=.03) and right parotid glands (P=.006). The computation including DIR and dose accumulation was ultrafast (∼45 seconds) with registration accuracy at the subvoxel level. Conclusions: A systematic analysis of anatomic variations in the H&N region and their dosimetric consequences is critical in improving treatment efficacy. Nearly real

  14. The Effect of Electrode Designs Based on the Anatomical Heart Location for the Non-Contact Heart Activity Measurement.

    Science.gov (United States)

    Gi, Sun Ok; Lee, Young-Jae; Koo, Hye Ran; Lee, Seung Pyo; Lee, Kang-Hwi; Kim, Kyeng-Nam; Kang, Seung-Jin; Lee, Joo Hyeon; Lee, Jeong-Whan

    2015-12-01

    This research is an extension of a previous research [1] on the different effects of sensor location that is relatively suitable for heart rate sensing. This research aimed to elucidate the causes of wide variations in heart rate measurements from the same sensor position among subjects, as observed in previous research [1], and to enhance designs of the inductive textile electrode to overcome these variations. To achieve this, this study comprised two parts: In part 1, X-ray examinations were performed to determine the cause of the wide variations noted in the findings from previous research [1], and we found that at the same sensor position, the heart activity signal differed with slight differences in the positions of the heart of each subject owing to individual differences in the anatomical heart location. In part 2, three types of dual-loop-type textile electrodes were devised to overcome variations in heart location that were confirmed in part 1 of the study. The variations with three types of sensor designs were compared with that with a single-round type of electrode design, by using computer simulation and by performing a t-test on the data obtained from the experiments. We found that the oval-oval shaped, dual-loop-type textile electrode was more suitable than the single round type for determining morphological characteristics as well as for measuring appropriate heart activity signals. Based on these results, the oval-oval, dual-loop-type was a better inductive textile electrode that more effectively overcomes individual differences in heart location during heart activity sensing based on the magnetic-induced conductivity principle. PMID:26490149

  15. The Effect of Electrode Designs Based on the Anatomical Heart Location for the Non-Contact Heart Activity Measurement.

    Science.gov (United States)

    Gi, Sun Ok; Lee, Young-Jae; Koo, Hye Ran; Lee, Seung Pyo; Lee, Kang-Hwi; Kim, Kyeng-Nam; Kang, Seung-Jin; Lee, Joo Hyeon; Lee, Jeong-Whan

    2015-12-01

    This research is an extension of a previous research [1] on the different effects of sensor location that is relatively suitable for heart rate sensing. This research aimed to elucidate the causes of wide variations in heart rate measurements from the same sensor position among subjects, as observed in previous research [1], and to enhance designs of the inductive textile electrode to overcome these variations. To achieve this, this study comprised two parts: In part 1, X-ray examinations were performed to determine the cause of the wide variations noted in the findings from previous research [1], and we found that at the same sensor position, the heart activity signal differed with slight differences in the positions of the heart of each subject owing to individual differences in the anatomical heart location. In part 2, three types of dual-loop-type textile electrodes were devised to overcome variations in heart location that were confirmed in part 1 of the study. The variations with three types of sensor designs were compared with that with a single-round type of electrode design, by using computer simulation and by performing a t-test on the data obtained from the experiments. We found that the oval-oval shaped, dual-loop-type textile electrode was more suitable than the single round type for determining morphological characteristics as well as for measuring appropriate heart activity signals. Based on these results, the oval-oval, dual-loop-type was a better inductive textile electrode that more effectively overcomes individual differences in heart location during heart activity sensing based on the magnetic-induced conductivity principle.

  16. 3DCT Features of the Pediatric Anatomic Variations of the Interparietal Bone%儿童顶间骨解剖变异的3DCT特征

    Institute of Scientific and Technical Information of China (English)

    刘俊刚; 李欣; 杨扬

    2013-01-01

    Objective To evaluate 3DCT features of anatomic variations of the interparietal bone. Methods CT imag-ings of 402 patients (exclude recent trauma) who underwent CT examination were analyzed. Maximum intensity projection ( MIP) and volume-rendered image ( VR) reconstructions were performed at workstation. CT features of anatomic variations of the interparietal bone, including appearance, location were analyzed. Results 89 cases of anatomic variation were found,which can be devided into penetrating type and non penetrating type. The penetrating type have multiple manifestations, which can be subdivided into type a to f. The non penetrating type included Suturae Mendosa and superior median fissure. Conclusion The anatomic variations of interparietal bone are numerous, which can be well displayed with 3DCT.%目的 探讨儿童顶间骨解剖变异的3DCT特征.方法 搜集2010年2月至2012年3月间在排除近期明确外伤史而怀疑颅内疾病于我院行螺旋CT检查的患儿402例.采用最大密度投影及容积再现技术观察顶间骨的变异情况,总结其部位、形态及其走行.结果 402例中存在顶间骨变异者89例(22.1%),包括贯通缝型和未贯通缝型.含贯通缝的顶间骨变异表现多样,将最多见者分为a~f型,含未贯通缝的顶间骨变异分为两种类型,假缝19例,上正中裂16例.结论 儿童顶间骨变异类型多样,直观的3D-CT图像可以明确变异位置及形态.

  17. Anatomical imaging for radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Evans, Philip M [Joint Physics Department, Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Downs Road, Sutton, Surrey SM2 5PT (United Kingdom)], E-mail: phil.evans@icr.ac.uk

    2008-06-21

    scans is taken on different days. Both allow planning to account for variability intrinsic to the patient. Treatment verification has been carried out using a variety of technologies including: MV portal imaging, kV portal/fluoroscopy, MVCT, conebeam kVCT, ultrasound and optical surface imaging. The various methods have their pros and cons. The four x-ray methods involve an extra radiation dose to normal tissue. The portal methods may not generally be used to visualize soft tissue, consequently they are often used in conjunction with implanted fiducial markers. The two CT-based methods allow measurement of inter-fraction variation only. Ultrasound allows soft-tissue measurement with zero dose but requires skilled interpretation, and there is evidence of systematic differences between ultrasound and other data sources, perhaps due to the effects of the probe pressure. Optical imaging also involves zero dose but requires good correlation between the target and the external measurement and thus is often used in conjunction with an x-ray method. The use of anatomical imaging in radiotherapy allows treatment uncertainties to be determined. These include errors between the mean position at treatment and that at planning (the systematic error) and the day-to-day variation in treatment set-up (the random error). Positional variations may also be categorized in terms of inter- and intra-fraction errors. Various empirical treatment margin formulae and intervention approaches exist to determine the optimum strategies for treatment in the presence of these known errors. Other methods exist to try to minimize error margins drastically including the currently available breath-hold techniques and the tracking methods which are largely in development. This paper will review anatomical imaging techniques in radiotherapy and how they are used to boost the therapeutic benefit of the treatment. (topical review)

  18. The effect of anatomical factors on mortality rates after endovascular aneurysm repair

    Science.gov (United States)

    Derih, Ay; Burak, Erdolu; Gunduz, Yumun; Yumun, Aydin; Ahmet, Demir; Hakan, Ozkan; Osman, Tiryakioglu; Kamuran, Erkoc

    2016-01-01

    Summary Objective The objective of this study was to investigate the effect of anatomical characteristics on mortality rates after endovascular aneurysm repair (EVAR). Methods We investigated 56 EVAR procedures for infrarenal aortic aneurysms performed between January 2010 and December 2013, and the data were supplemented with a prospective review. The patients were divided into two groups according to the diameter of the aneurysm. Group I (n = 30): patients with aneurysm diameters less than 6 cm, group II (n = 26): patients with aneurysm diameters larger than 6 cm. The pre-operative anatomical data of the aneurysms were noted and the groups were compared with regard to postoperative results. Results There were no correlations between diameter of aneurysm (p > 0.05), aneurysm neck angle (p > 0.05) and mortality rate. The long-term mortality rate was found to be high in patients in whom an endoleak occurred. Conclusion We found that aneurysm diameter did not have an effect on postoperative mortality rates. An increased EuroSCORE value and the development of endoleaks had an effect on long-term mortality rates. PMID:26207946

  19. Effect of Salinity on Growth, Xylem Structure and Anatomical Characteristics of Soybean

    Directory of Open Access Journals (Sweden)

    Aria DOLATABADIAN

    2011-03-01

    Full Text Available This research was conducted in order to evaluation the salinity stress effect on growth parameters and stem anatomical changes of soybean grown under controlled conditions. Soybean seeds were surface sterilized and then sown into plastic pots filled up with perlite and vermiculite. Seeds were irrigated with Broughton and Dilworth solution daily. At full folded cotyledons stage (5 day after sowing, salinity stress was induced by adding NaCl into nutrition solution with final concentration of 0, 25, 50 and 100 mM. Thirty days after sowing plants were harvested and growth parameters and anatomical changes were evaluated. The results showed that, salinity stress was significantly decreased shoot and root weight either fresh weight or dry weight, in addition, total plant weight, plant height and leaf number were decreased due to salinity stress. Interestingly, leaf area was not affected by salinity stress. Stem microscopic study demonstrated that, salinity stress significantly increased cutin mass and trichome density on epidermal cells. On the other hand, cortex thickness was decreased because of salinity stress while xylem thickness had upward increase when soybean plants were grown under salinity stress especially high level of salinity. Additionally, there were changed in xylem formation and arrangement in stressed plants.

  20. Dosimetric Effect of Online Image-Guided Anatomical Interventions for Postprostatectomy Cancer Patients

    International Nuclear Information System (INIS)

    Purpose: To assess daily variations in delivered doses in postprostatectomy patients, using kilovoltage cone-beam CT (CBCT) datasets acquired before and after interventions to correct for observed distortions in volume/shape of rectum and bladder. Methods and Materials: Seventeen consecutive patients treated with intensity-modulated radiotherapy to the prostate bed were studied. For patients with large anatomical variations, quantified by either a rectal wall displacement of >5 mm or bladder volume change of >50% on the CBCT compared with the planning CT, an intervention was performed to adjust the rectum and/or bladder filling. Cumulative doses over the pre- and post-intervention fractions were calculated by tracking the position of the planning CT voxels on different CBCTs using a deformable surface-mapping algorithm. Dose and displacements vectors were projected on two-dimensional maps, the minimal dose received by the highest 95% of the planing target volume (PTV D95) and the highest 10% of the rectum volume (D10) as well as the bladder volume receiving >2 Gy (V2) were evaluated. Results: Of 544 fractions, 96 required intervention. Median (range) number of interventions per patient was 5 (2-12). Compared with the planning values, the mean (SD) pre- vs. postintervention value for PTV D95 was -2% (2%) vs. -1% (2%) (p < 0.12), for rectum D10 was -1% (4%) vs. +1% (4%) (p < 0.24), and for bladder V2 was +6% vs. +20% (p < 0.84). Conclusions: Interventions to reduce treatment volume deformations due to bladder and rectum fillings are not necessary when patients receive daily accurate CBCT localization, and the frequency of those potential interventions is low. However, for hypofractionated treatments, the relative frequency can significantly increase, and interventions can become more dosimetrically beneficial.

  1. Anatomic and functional leg-length inequality: A review and recommendation for clinical decision-making. Part I, anatomic leg-length inequality: prevalence, magnitude, effects and clinical significance

    Directory of Open Access Journals (Sweden)

    Knutson Gary A

    2005-07-01

    Full Text Available Abstract Background Leg-length inequality is most often divided into two groups: anatomic and functional. Part I of this review analyses data collected on anatomic leg-length inequality relative to prevalence, magnitude, effects and clinical significance. Part II examines the functional "short leg" including anatomic-functional relationships, and provides an outline for clinical decision-making. Methods Online database – Medline, CINAHL and MANTIS – and library searches for the time frame of 1970–2005 were done using the term "leg-length inequality". Results and Discussion Using data on leg-length inequality obtained by accurate and reliable x-ray methods, the prevalence of anatomic inequality was found to be 90%, the mean magnitude of anatomic inequality was 5.2 mm (SD 4.1. The evidence suggests that, for most people, anatomic leg-length inequality does not appear to be clinically significant until the magnitude reaches ~ 20 mm (~3/4". Conclusion Anatomic leg-length inequality is near universal, but the average magnitude is small and not likely to be clinically significant.

  2. Age-Dependent Effects of Haptoglobin Deletion in Neurobehavioral and Anatomical Outcomes Following Traumatic Brain Injury

    Science.gov (United States)

    Glushakov, Alexander V.; Arias, Rodrigo A.; Tolosano, Emanuela; Doré, Sylvain

    2016-01-01

    Cerebral hemorrhages are common features of traumatic brain injury (TBI) and their presence is associated with chronic disabilities. Recent clinical and experimental evidence suggests that haptoglobin (Hp), an endogenous hemoglobin-binding protein most abundant in blood plasma, is involved in the intrinsic molecular defensive mechanism, though its role in TBI is poorly understood. The aim of this study was to investigate the effects of Hp deletion on the anatomical and behavioral outcomes in the controlled cortical impact model using wildtype (WT) C57BL/6 mice and genetically modified mice lacking the Hp gene (Hp−∕−) in two age cohorts [2–4 mo-old (young adult) and 7–8 mo-old (older adult)]. The data obtained suggest age-dependent significant effects on behavioral and anatomical TBI outcomes and recovery from injury. Moreover, in the adult cohort, neurological deficits in Hp−∕− mice at 24 h were significantly improved compared to WT, whereas there were no significant differences in brain pathology between these genotypes. In contrast, in the older adult cohort, Hp−∕− mice had significantly larger lesion volumes compared to WT, but neurological deficits were not significantly different. Immunohistochemistry for ionized calcium-binding adapter molecule 1 (Iba1) and glial fibrillary acidic protein (GFAP) revealed significant differences in microglial and astrocytic reactivity between Hp−∕− and WT in selected brain regions of the adult but not the older adult-aged cohort. In conclusion, the data obtained in the study provide clarification on the age-dependent aspects of the intrinsic defensive mechanisms involving Hp that might be involved in complex pathways differentially affecting acute brain trauma outcomes. PMID:27486583

  3. Variation Within Trees of Wood Anatomical Properties in Chinese-Fir Plantation and Their Relationship Modeling Equations

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    A comprehensive analysis on the variation pattern of early- and latewood tracheid morphological parameters along tree (Cunninghamia lanceolata Hook.) height, including length and width, wall thickness, tissue proportion, cell wall percentage, width of growth rings, and on the relationship among them are conducted. The results indicate an initially rapid and then gentle increase of tracheid length and width, thickness of the radial wall and tangential wall of tracheid, area percentage of tracheid from pi...

  4. Anatomical variations in the origins of the celiac axis and the superior mesenteric artery: MDCT angiographic findings and their probable embryological mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yi; Cheng, Cheng; Wang, Lu; Li, Ran; Chen, Jin-hua; Gong, Shui-gen [Institute of Surgery Research, Daping Hospital, Third Military Medical University, Department of Radiology, Chongqing (China)

    2014-08-15

    To identify the spectrum and prevalence of anatomical variations in the origin of the celiac axis (CA), the superior mesenteric artery (SMA) and their major branches by using multidetector computed tomographic (MDCT) angiography. A retrospective evaluation was carried out on 1,500 abdominal MDCT angiography images. The aortic origins of the CA, the SMA and their major branch patterns were investigated. Normal aortic origins of CA and SMA were noted in 1,347 (89.8 %) patients. Seven types of CA and SMA origin variants were identified in 153 (10.2 %) patients. The three most common variations were hepatomesenteric trunk (67 patients, 4.47 %), celiomesenteric trunk (CMT) (51 patients, 3.4 %) and splenomesenteric trunk (18 patients, 1.2 %). An evaluation of CMT was classified as long (34 patients, 66.7 %) or short (17 patients, 33.3 %) subtypes, compared with the length of the common trunk. Further CMT classification was based on the origin of the left gastric artery: subtype I, 26 patients (53.1 %); subtype II, 5 patients (10.2 %); subtype III, 15 patients (30.6 %); subtype IV, 3 patients (6.1 %). Dislocation interruption, incomplete interruption and persistence of the longitudinal anastomosis could be the embryological mechanisms of the variant origins of the CA, the SMA and their major branches. (orig.)

  5. An Analysis of Visibility and Anatomic Variations of Mandibular Canal in Digital Panoramic Radiographs of Dentulous and Edentulous Patients in Northern Iran Populations

    Directory of Open Access Journals (Sweden)

    Somayeh Nemati

    2016-06-01

    Full Text Available Statement of the Problem: Insufficient information about the anatomical positions and structure of mandibular canal provokes unwanted damage to this important structure of mandible. Purpose: The aim of this study was to determine the visibility and anatomical variations of mandibular canal in digital panoramic radiographs of dentulous and edentulous patients in a sample of Iranian population. Materials and Method: In this retrospective-analytical research, 249 digital panoramic radiographs in dentulous group and 126 in edentulous group were studied by an expert oral and maxillofacial radiologist. In both groups, the visibility of canal borders in anterior, middle, and posterior areas were examined. In dentulous group, the distance between the canal and apex of the first and second molars were measured. Canal-to-alveolar crest distance and lower mandibular border was measured in three different points for both groups. Finally, the upper-lower positions of canals were deter-mined. Results: In both groups, most visibility occurred in 1/3 of posterior and the least visibility was detected in 1/3 of anteri-or, with the intermediate being the most visible part (Type 2. There was no significant difference between the left and right sides in all cases. In dentulous group, no correlation was found between the visibility, age, and gender (p> 0.05; however, canal position was related to gender (p= 0.03 and p= 0.04 in right and left sides, respectively. High position was more frequent in females and intermediate position was more common in males. In edentulous group, no correla-tion was found between age, gender, and canal position (p> 0.05. Conclusion: The most visibility of mandibular canal was in its third posterior and the least was in its third anterior part. Although the middle position of canal was more frequently visible than the high position in this study, it does not refute the possibility of damaging the mandibular canal in critical surgeries.

  6. Successful thoracoscopic lobectomy for lung cancer in a patient with anatomic variation of the left inferior pulmonary vein

    Directory of Open Access Journals (Sweden)

    Nakano,Hideharu

    2007-04-01

    Full Text Available We present a case of primary lung cancer with a rare distribution pattern of left inferior pulmonary vein (PV, encountered in the thoracoscopic left lower lobectomy. Thoracoscopic observation revealed 2 trunks of inferior PV (ventral and dorsal branch at the stem level. The ventral trunk consisted of a branch of vein (V(5 from the lingular segment and venous ramifications (V(8a, V(9 and V(10a from the basal segment. On the other hand, a branch of vein (V(6 from the superior segment in the lower lobe and other veins (V(8b and V(10b + c from the basal segment emptied together into the dorsal trunk. We successfully carried out a thoracoscopic left lower lobectomy without excision of the aberrant vein (V(5. Retrospective review of the preoperative chest CT demonstrates the double trunk inferior PV and the aberrant lingular branch emptying with V(8a into the ventral trunk. Knowledge of the branching variations of PV from preoperative evaluations leads to appropriate thoracoscopic procedures for lung cancer.

  7. Effects of salinity on anatomical features and physiology of a semi-mangrove plant Myoporum bontioides.

    Science.gov (United States)

    Xu, H M; Tam, N F Y; Zan, Q J; Bai, M; Shin, P K S; Vrijmoed, L L P; Cheung, S G; Liao, W B

    2014-08-30

    The effect of different concentrations of NaCl, 0, 100, 200, 300 and 400 mM, on the anatomical features and physiology of Myoporum bontioides was investigated. The photosynthetic rates (Pn) were significantly reduced by salt stress, with the lowest values at 400 mM NaCl. The content of malondialdehyde (MDA), proline and soluble sugar, as well as the activities of peroxidase (POD) and catalase (CAT) increased at the beginning, but became similar to the control as the experiment proceeded. The NaCl effect on superoxide dismutase (SOD) was different from the other parameters, with a significant reduction at 400 mM NaCl at Day 7. Salt glands were found in both upper and lower epidermis, and the ratios of the thickness of palisade to spongy mesophyll tissues increased with NaCl concentrations. The medullary ray was clearly damaged by NaCl at levels of 200 and 300 mM. These results demonstrated that M. bontioides could adapt to a relatively low salinity, and was not a halophilous species.

  8. Interactive effects of elevated C02 and temperature on the anatomical characteristics of leaves in eleven species

    Institute of Scientific and Technical Information of China (English)

    HAN Mei; JI Chengjun; ZUO Wenyun; HE Jinsheng

    2007-01-01

    The anatomical features of leaves in 11 species of plants grown in a temperature gradient and a temperature + CO2 gradient were studied.The palisade parenchyma thickness,the spongy parenchyma thickness and the total leaf thickness were measured and analyzed to investigate the effects of elevated temperature and CO2 on the anatomical characteristics of the leaves.Our results show that with the increase of temperature,the leaf thickness of C4 species increased while the leaf thickness of C3 species showed no constant changes.With increased CO2,seven out of nine C3 species exhibited increased total leaf thickness.In C4 species,leaf thickness decreased.As for the trend on the multi-grades,the plants exhibited linear or non-linear changes.With the increase of temperature or both temperature and CO2 for the 11 species investigated,leaf thickness varied greatly in different plants (species) and even in different branches on the same plant.These results demonstrated that the effect of increasing CO2 and temperature on the anatomical features of the leaves were species-specific.Since plant structures are correlated with plant functions,the changes in leaf anatomical characteristics in elevated temperature and CO2 may lead to functional differences.

  9. Effect of anatomical and chemical structure in the permeability of "Amapá" wood

    Directory of Open Access Journals (Sweden)

    Edy Eime Pereira Baraúna

    2014-12-01

    Full Text Available This paper aimed to study the permeability to air and liquid, in the longitudinal direction of "amapá" wood (Brosimum parinarioides Ducke, originating from the Amazon Forest. Furthermore, the influence of anatomical and chemical characteristics in the permeability of the wood was investigated. For this study, samples were collected from three trees, in the state of Pará, Brazil, and submitted to permeability test, anatomical characterization, and chemical analyses. The permeability to the air of the "amapá" wood was estimated at 63.7.10-9 m3.[m.(N.m-2.s]-1 and to the liquid was 2.07.10-9 m3.[m.(N.m-2.s]-1. There were low correlations between air and liquid permeability and the anatomical features.

  10. [The effect of central anatomical single-bundle versus anatomical double-bundle reconstruction of the anterior cruciate ligament on knee stability. a clinical study].

    Science.gov (United States)

    Komzák, M; Hart, R; Smíd, P; Puskeiler, M

    2014-01-01

    most important factors in restoring physiological kinematics of the joint after ACL injury. Since there are not many studies comparing knee rotational stability after CASB with that after DB reconstructions, the results presented here may contribute to selecting the optimal method of ACL reconstruction. CONCLUSIONS The results show that, in ACL reconstruction, the DB technique provides better stability to the knee, in both APT and rotation, than the CASB method. The latter has the same effect on knee stability as the presence of the AM bundle alone. When the PL bundle is added, knee stability, in both APT and internal/external rotation, is increased in comparison with central single-bundle ACL repair. Key words:anterior cruciate ligament, navigation, central anatomical single-bundle reconstruction, double-bundle reconstruction.

  11. Detection of simulated microcalcifications in digital mammography: effects of quantum and anatomic noises: preliminary study

    Science.gov (United States)

    Lai, Chao-Jen; Liu, Xinming; You, Zhicheng; Shen, Youtao; Zhong, Yuncheng; Chen, Lingyun; Han, Tao; Ge, Shuaiping; Yi, Ying; Geiser, William R.; Flores, David; Whitman, Gary J.; Yang, Wei T.; Shaw, Chris C.

    2010-04-01

    To study the effects of overlapping anatomy on microcalcification detection at various incident exposure levels. Images of an anthropomorphic breast phantom (RMI 169) overlapping with simulated microcalcifications ranging from 150 to 212 μm in size placed in two breast density regions, fatty and heterogeneously dense, were acquired with an a-Si/a-Se flat panel based digital mammography system (Selenia) operated with Mo-Mo target/filter combination at 28 kVp. The mammograms were exposed with 20, 30, 40, 60, 80, 120, 160, 240 and 325 mAs for varying the exposure level. A 4-AFC study was performed for evaluation of the detection performance. Four 400×400-pixel images were displayed as 2×2 array on a LCD flat panel based review workstation. One of the four images contained a cluster of five microcalcifications and was randomly placed in one of the four quadrants. A physicist was asked to select the image containing the microcalcifications and to report the number of visible microcalcifications. The fraction of correct responses was computed with two different criteria: (1) the selected images contained one or more microcalcifications, and (2) the selected images contained 4 or 5 visible microcalcifications. The statistical significance of the differences in fractions for different exposure levels and regions was evaluated. The results showed that, if visibility of one or more microcalcifications is required, the fractions of correct responses were 1 for all size groups and most exposure levels in both fatty and heterogeneously dense regions. If a visibility of 80% or more of the microcalcifications was required, the fractions of correct responses significantly decreased in both regions. The results indicated that microcalcification detection in the fatty region appeared to be mainly limited by the quantum noise, and that in the heterogeneously dense region may be limited by both the anatomic noise and the quantum noise.

  12. Effect of Calcium Phosphate–Hybridized Tendon Graft in Anatomic Single-Bundle ACL Reconstruction in Goats

    Science.gov (United States)

    Mutsuzaki, Hirotaka; Fujie, Hiromichi; Nakajima, Hiromi; Fukagawa, Makoto; Nomura, Shunsuke; Sakane, Masataka

    2016-01-01

    Background: We previously developed a novel technique using an alternate soaking process that improves tendon-bone healing by hybridizing the tendon graft with calcium phosphate (CaP). However, the effects of the CaP-hybridized tendon graft on anatomic single-bundle anterior cruciate ligament (ACL) reconstruction remain unclear. Purpose: To determine the effects of CaP-hybridized tendon grafts compared with untreated tendon grafts 6 months after anatomic single-bundle ACL reconstruction using a goat model. Study Design: Controlled laboratory study. Methods: Animals were divided into a CaP group (n = 5 goats) and a control group (n = 5 goats), and we analyzed (1) knee kinematics and in situ forces under applied anterior tibial loads of 50 N and internal tibial torque of 2.0 N·m in the grafts at full extension and at 60° and 90° of knee flexion, (2) the mean percentage of bone tunnel enlargement using computed tomography (CT), and (3) the histology of the tendon-bone interface. Results: The in situ forces under applied anterior tibial loads of 50 N at 60° and 90° of knee flexion in the CaP group were greater than those in the control group (P joint aperture sites of the anterior femoral and posterior tibial bone tunnel, was greater in the CaP group than that in the control group (P joint aperture site in both anterior femoral and posterior tibial tunnels 6 months after anatomic single-bundle ACL reconstruction in goats. The in situ forces under applied anterior tibial loads at greater flexion angles in the CaP group increased compared with controls. Clinical Relevance: Anatomic single-bundle ACL reconstruction using CaP-hybridized tendon grafts may lead to better postoperative knee function. PMID:27660798

  13. Anatomical basis of LMA variations drive to different photosynthetic and water storage strategies in two Sesleria species from mountain dry grasslands

    Science.gov (United States)

    Puglielli, Giacomo; Fiore Crescente, Maria; Frattaroli, Anna Rita; Gratani, Loretta

    2016-04-01

    Plant and leaf traits directly affect ecosystem processes ensuring carbon, nutrient and water exchanges between soil and atmosphere through the photosynthetic activity. Nevertheless, a great within sites variation in plant and leaf traits can be found resulting in different adaptive strategies in coexisting species. Leaf mass per unit of leaf area (LMA) is an important trait to understand plant functional ecology being the outcome of leaf anatomy and related to photosynthesis. We hypothesized that LMA was the main predictor of the adaptive strategies of Sesleria nitida (S1) and Sesleria juncifolia (S2), growing on the screes and on the crests of the summit area, respectively, on Mount Terminillo (Central Apennines, Loc. Sella di Leonessa, 1895 m a.s.l.). To test our hypothesis we broke LMA down into anatomical components, leaf tissue density (LTD) and thickness (LT) and then relating them to gas exchange parameters on twenty plants per species cultivated ex situ. LTD explained 69% of LMA variations in S1 while the relationship with LT was not significant. Moreover, LTD was negatively correlated with LT in S1 driving to a 17% higher volume of the intercellular air spaces, which increases the CO2 partial pressure at the carboxylation sites. This result was also attested by the significant relationship between LTD and both net photosynthesis per unit leaf area (Aa) and mass (Am) (R= 0.56 and -0.49, respectively), highlighting the role of LTD in determining the photosynthetic process in S1. LMA scaled with both LTD and LT explaining 82% and 70% of LMA variations in S2. Moreover, the positive relationship between LTD and LT (R2 = 0.52) highlighted a coordination between the variables in controlling the photosynthetic process. In particular, LTD and LT controlled the transactions of carbon and water through the leaf surface, being positively related to Aa (R= 0.93 and 0.79 for LTD and LT, respectively). Nevertheless, an increase in LT and LTD decreased Am (R = -0.9 and

  14. Noninvasive study of anatomic variations of the bile and pancreatic duct using magnetic resonance cholangiopancreatography; Estudio no invasivo de variantes anatomicas de la via biliar y pancreatica mediante colangiopancreatografia por resonancia magnetica (CPRM)

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, E.; Falco, J.; Campo, R.; Martin, J.; Brullet, E. [SDI-UDIAT Corporacio Sanitaria Parc Tauli. Sabadell (Spain); Espinos, J. [Hospital Mutua de Tarrasa (Spain)

    1999-07-01

    To identify anatomic variations of the bile duct and pancreatic duct and papillary anomalies by means of magnetic resonance cholangiopancreatography (MRCP) and determine their correlation with endoscopic retrograde cholangiopancreatography (ERCP) findings. Eighty-five patients were selected by means of a prospective study comparing MRCP and ERCP. Coronal and axial HASTE images and coronal and oblique coronal RARE images were acquired in all the patients. Four of the studies (6%) were excluded because of poor technical quality. Anatomic variations were observed in 26 cases (30.5%), including trifurcation (n=7; 27%), right hepatic duct draining into left hepatic duct (n=2, 7.7%), right hepatic duct draining into common bile duct (n=4; 15.4%), extrahepatic confluence (n=2; 7.7%), medial cystic duct (n=2; 7.7%), parallel cystic duct (n=3; 11.5%), juxtapapillary duodenal diverticulum (n=3; 11.5%) and pancreas divisum (n=3; 11.5%). A good correlation was observed between the MRCP and ERCP findings. The introduction of MRCP into the noninvasive study of biliary disease may be useful in the detection of anatomic variations relevant to laparoscopic surgery and other endoscopic and interventional techniques. (Author) 11 refs.

  15. Anatomical and genetic variation of western Oxyloma (Pulmonata: Succineidae) concerning the endangered Kanab ambersnail (Oxyloma haydeni kanabense) in Arizona and Utah

    Science.gov (United States)

    Culver, Melanie; Herrmann, Hans-Werner; Miller, Mark; Roth, Barry; Sorenson, Jeff

    2013-01-01

    more closely related to other, non-endangered ambersnail populations across the Southwest. In contrast, the Kanab ambersnail population at Vaseys Paradise appeared to be genetically distinct from all other ambersnail populations studied. Management options for the ambersnail population at Vaseys Paradise, at the time of this study, conflict with ecosystem-wide measures proposed to benefit other natural resources in the Grand Canyon. The U.S. Fish and Wildlife Service will not revise the 1995 Kanab Ambersnail Recovery Plan until further genetic and anatomical analyses provide more fine-scale taxonomic resolution of the identity of Oxyloma populations on the Colorado Plateau and elsewhere in the American Southwest. Likewise, interagency cooperators cannot revise down-listing criteria for the Kanab ambersnail until substantial evidence is provided identifying distinct Oxyloma taxa or a larger group of conspecifics that reasonably could be managed as one species. Therefore, given the current controversy about the taxonomy of Oxyloma and the endangered Kanab ambersnail, new detailed analyses were completed of morphological and genetic variation from many Oxyloma specimens collected at 12 western North American locations. These new data have allowed us to evaluate many issues related to Kanab ambersnail taxonomy. Using this dataset, the study of shells and anatomy indicates that the holotype of Oxyloma haydeni kanabense plausibly can be regarded as a member of the same species as the populations of Oxyloma analyzed in this study. Additionally, the presence of gene flow among all populations is evidence that they are members of the same species. Almost all the observed genetic diversity can be accounted for by short-distance or long-distance dispersal events between populations in this study. Our major taxonomic conclusion is that all samples collected for this study were drawn from populations of the same species.

  16. 背胰形态变异的影像学特征%Imaging features of anatomical variations of the dorsal pancreas

    Institute of Scientific and Technical Information of China (English)

    王玉涛; 汪建华; 张建; 邵成伟; 涂灿; 王海涛; 左长京

    2015-01-01

    目的 总结背胰形态变异的影像学特征及其临床意义.方法 回顾性分析47例背胰形态变异患者的CT、MRI资料,分类解释其影像学特征.结果 (1)背胰缩小类.背胰发育不全(n=7):胰腺长度(91.59 ±22.39) mm,呈“短胰腺”表现,4例(4/7)胰头增大,存留胰腺呈“蝌蚪状”,其中3例(3/7)形成环状胰腺;2例(2/7)合并多脾综合征、下腔静脉肝段缺如.(2)背胰增大类.①胰尾增宽(n=18):胰尾最大宽径(36.12±6.59)mm,超过胰体宽径,胰腺呈类似“哑铃状”表现.②背胰局部隆起(n=13):胰颈、体及尾部腹侧缘的局限性隆起,高度(15.72±2.65) mm,长度(18.59±3.64) mm,多位于胰颈.(3)背胰相关分裂类.①背胰脂肪裂隙(n=7):脂肪裂隙宽度(3.51±2.42) mm,深度(19.45±5.84) mm,表现为线条状脂肪密度(信号)影,5例(5/7)位于胰体、尾,2例(2/7)位于腹胰与背胰融合区.②胰尾分叉(n=3):胰尾局限性分叉呈“燕尾状”表现,最大宽径(26.63±1.75) mm,分叉角度(99.27±30.73)度.结论 背胰发育异常可导致胰腺多种形态改变,影像学表现有一定特征,了解胰腺的发育过程,熟悉该类变异的影像学表现有助于正确诊断,从而避免不必要的临床治疗.%Objective To evaluate imaging features and clinical significance of anatomical variations of the dorsal pancreas.Methods CT and MR imaging data of 47 cases with variations of the dorsal pancreas were collected.Imaging characteristics of the dorsal pancreas were analysed.Results (1) Narrow dorsal pancreas:the agenesis of dorsal pancreas (7 cases) appeared as "short pancreas",their length was (91.59 ± 22.39) mm.4 cases of pancreatic head volume increased,with "tadpole-like" retention of the pancreas,including 3 cases of annular pancreas.2 cases with polysplenia syndrome and congenital abscence of the hepatic segment of inferior vena cava.(2) Abnormaly enlarged dorsal pancreas:①the broadening of the pancreatic tail (n =18):the maximum

  17. Anatomic study of infrapopliteal vessels.

    Science.gov (United States)

    Lappas, D; Stavropoulos, N A; Noussios, G; Sakellariou, V; Skandalakis, P

    2012-08-01

    The purpose of this project is to study and analyse the anatomical variations of the infrapopliteal vessels concerning their branching pattern. A reliable sample of one hundred formalin-fixed adult cadavers was dissected by the Anatomical Laboratory of Athens University. The variations can be classified in the following way: the normal branching of the popliteal artery was present in 90%. The remainder revealed variant branching patterns: hypoplastic or aplastic posterior tibial artery and the pedis arteries arising from the peroneal (3%); hypoplastic or aplastic anterior tibial artery (1.5%); and the dorsalis pedis formed by two equal branches, arising from the peroneal and the anterior tibial artery (2%). The variations were more frequent in females and in short-height individuals. Knowledge of these variations is rather important for any invasive technic concerning lower extremities.

  18. SU-C-210-05: Evaluation of Robustness: Dosimetric Effects of Anatomical Changes During Fractionated Radiation Treatment of Pancreatic Cancer Patients

    Energy Technology Data Exchange (ETDEWEB)

    Horst, A van der; Houweling, A C; Bijveld, M M C; Visser, J; Bel, A [Academic Medical Center, Amsterdam, Noord-Holland (Netherlands)

    2015-06-15

    Purpose: Pancreatic tumors show large interfractional position variations. In addition, changes in gastrointestinal air volume and body contour take place during treatment. We aim to investigate the robustness of the clinical treatment plans by quantifying the dosimetric effects of these anatomical changes. Methods: Calculations were performed for up to now 3 pancreatic cancer patients who had intratumoral fiducials for daily CBCT-based positioning during their 3-week treatment. For each patient, deformable image registration of the planning CT was used to assign Hounsfield Units to each of the 13—15 CBCTs; air volumes and body contour were copied from CBCT. The clinical treatment plan was used (CTV-PTV margin = 10 mm; 36Gy; 10MV; 1 arc VMAT). Fraction dose distributions were calculated and accumulated. The V95% of the clinical target volume (CTV) and planning target volume (PTV) were analyzed, as well as the dose to stomach, duodenum and liver. Dose accumulation was done for patient positioning based on the fiducials (as clinically used) as well as for positioning based on bony anatomy. Results: For all three patients, the V95% of the CTV remained 100%, for both fiducial- and bony anatomy-based positioning. For fiducial-based positioning, dose to duodenum en stomach showed no discernable differences with planned dose. For bony anatomy-based positioning, the PTV V95% of the patient with the largest systematic difference in tumor position (patient 1) decreased to 85%; the liver Dmax increased from 33.5Gy (planned) to 35.5Gy. Conclusion: When using intratumoral fiducials, CTV dose coverage was only mildly affected by the daily anatomical changes. When using bony anatomy for patient positioning, we found a decline in PTV dose coverage due to the interfractional tumor position variations. Photon irradiation treatment plans for pancreatic tumors are robust to variations in body contour and gastrointestinal gas, but the use of fiducial-based daily position verification

  19. SU-C-210-05: Evaluation of Robustness: Dosimetric Effects of Anatomical Changes During Fractionated Radiation Treatment of Pancreatic Cancer Patients

    International Nuclear Information System (INIS)

    Purpose: Pancreatic tumors show large interfractional position variations. In addition, changes in gastrointestinal air volume and body contour take place during treatment. We aim to investigate the robustness of the clinical treatment plans by quantifying the dosimetric effects of these anatomical changes. Methods: Calculations were performed for up to now 3 pancreatic cancer patients who had intratumoral fiducials for daily CBCT-based positioning during their 3-week treatment. For each patient, deformable image registration of the planning CT was used to assign Hounsfield Units to each of the 13—15 CBCTs; air volumes and body contour were copied from CBCT. The clinical treatment plan was used (CTV-PTV margin = 10 mm; 36Gy; 10MV; 1 arc VMAT). Fraction dose distributions were calculated and accumulated. The V95% of the clinical target volume (CTV) and planning target volume (PTV) were analyzed, as well as the dose to stomach, duodenum and liver. Dose accumulation was done for patient positioning based on the fiducials (as clinically used) as well as for positioning based on bony anatomy. Results: For all three patients, the V95% of the CTV remained 100%, for both fiducial- and bony anatomy-based positioning. For fiducial-based positioning, dose to duodenum en stomach showed no discernable differences with planned dose. For bony anatomy-based positioning, the PTV V95% of the patient with the largest systematic difference in tumor position (patient 1) decreased to 85%; the liver Dmax increased from 33.5Gy (planned) to 35.5Gy. Conclusion: When using intratumoral fiducials, CTV dose coverage was only mildly affected by the daily anatomical changes. When using bony anatomy for patient positioning, we found a decline in PTV dose coverage due to the interfractional tumor position variations. Photon irradiation treatment plans for pancreatic tumors are robust to variations in body contour and gastrointestinal gas, but the use of fiducial-based daily position verification

  20. The effects of anatomical information and observer expertise on abnormality detection task

    Science.gov (United States)

    Zhang, L.; Cavaro-Ménard, C.; Le Callet, P.; Cooper, L. H. K.; Hunault, G.; Tanguy, J.-Y.

    2011-03-01

    This paper presents a novel study investigating the influences of Magnetic Resonance (MR) image anatomical information and observer expertise on an abnormality detection task. MRI is exquisitely sensitive for detecting brain abnormalities, particularly in the evaluation of white matter diseases, e.g. multiple sclerosis (MS). For this reason, MS lesions are simulated as the target stimuli for detection in the present study. Two different image backgrounds are used in the following experiments: a) homogeneous region of white matter tissue, and b) one slice of a healthy brain MR image. One expert radiologist (more than 10 years' experience), three radiologists (less than 5 years' experience) and eight naïve observers (without any prior medical knowledge) have performed these experiments, during which they have been asked different questions dependent upon level of experience; the three radiologists and eight naïve observers were asked if they were aware of any hyper-signal, likely to represent an MS lesion, while the most experienced consultant was asked if a clinically significant sign was present. With the percentages of response "yes" displayed on the y-axis and the lesion intensity contrasts on the x-axis, psychometric function is generated from the observer' responses. Results of psychometric functions and calculated thresholds indicate that radiologists have better hyper-signal detection ability than naïve observers, which is intuitively shown by the lower simple visibility thresholds of radiologists. However, when radiologists perform a task with clinical implications, e.g. to detect a clinically significant sign, their detection thresholds are elevated. Moreover, the study indicates that for the radiologists, the simple visibility thresholds remain the same with and without the anatomical information, which reduces the threshold for the clinically significant sign detection task. Findings provide further insight into human visual system processing for this

  1. 凹唇姜属(Boesenbergia O. Kuntze)和山柰属(Kaempferia L.)(姜科)叶的解剖学%ANATOMICAL VARIATIONS IN LEAVES OF BOESENBERGIA O. KUNTZE AND KAEMPFER1A L. SPECIES (ZINGIBERACEAE)

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Leaf anatomical variations between species of Boesenbergia (B. curtisii, B. prainiana, B. rotunda and B. plicata) and Kaempferia (K. pulchra, K. galanga, K. gilbertii, K. rotunda, K. parviflora and K. angustifolia) were studied in order to investigate anatomical variations which could be used to distinguish species. Results show that there are variations in the type of stomata, the structure of the midrib, the outlines of the leaf margin and petiole in transverse section, and the presence or absence of abaxial or adaxial hypodermis and trichomes in the lamina. The results suggest that a combination of these characters is useful in distinguishing the species studied.%通过凹唇姜属(Boesenbergia curtisii, B. prainiana, B. rotunda 和 B. plicata)和山柰属(Kaempferia pulchra, K. galanga, K. gilbertii, K. rotunda, K. parviflora 和 K. angustifolia)种间叶解剖学变化的研究,寻找能用于鉴别种的解剖学特征。结果显示变化表现在气孔的类型、中脉的结构、叶缘和叶柄横切面轮廓、叶片的远轴面或近轴面下皮层和毛状体的出现或缺如。研究表明这些特征的联合对已研究的种的鉴别是有用的。

  2. Effect of exercise intervention on thigh muscle volume and anatomical cross-sectional areas--quantitative assessment using MRI.

    Science.gov (United States)

    Hudelmaier, Martin; Wirth, Wolfgang; Himmer, Maria; Ring-Dimitriou, Susanne; Sänger, Alexandra; Eckstein, Felix

    2010-12-01

    The objective of this study was to evaluate the location-specific magnitudes of an exercise intervention on thigh muscle volume and anatomical cross-sectional area, using MRI. Forty one untrained women participated in strength, endurance, or autogenic training for 12 weeks. Axial MR images of the thigh were acquired before and after the intervention, using a T1-weighted turbo-spin-echo sequence (10 mm sections, 0.78 mm in-plane resolution). The extensor, flexor, adductor, and sartorius muscles were segmented between the femoral neck and the rectus femoris tendon. Muscle volumes were determined, and anatomical cross-sectional areas were derived from 3D reconstructions at 10% (proximal-to-distal) intervals. With strength training, the volume of the extensors (+3.1%), flexors (+3.5%), and adductors (+3.9%) increased significantly (P muscle volumes. The study shows that MRI can be used to monitor location-specific effects of exercise intervention on muscle cross-sectional areas, with the proximal aspect of the thigh muscles being most responsive. PMID:20665894

  3. Effect of anatomical variability, reconstruction algorithms and scattered photons on the SPM output of brain PET studies.

    Science.gov (United States)

    Aguiar, P; Pareto, D; Gispert, J D; Crespo, C; Falcón, C; Cot, A; Lomeña, F; Pavía, J; Ros, D

    2008-02-01

    Statistical parametric mapping (SPM) has become the standard technique to statistically evaluate differences between functional images. The aim of this paper was to assess the effect of anatomical variability of skull, the reconstruction algorithm and the scattering of photons in the brain on the output of an SPM analysis of brain PET studies. To this end, Monte Carlo simulation was used to generate suitable PET sinograms and bootstrap techniques were employed to increase the reliability of the conclusions. Activity distribution maps were obtained by segmenting thirty nine T1-weighted magnetic resonance images. Foci were placed on the posterior cingulate cortex (PCC) and the superior temporal cortex (STC) and activation factors ranging between -25% and +25% were simulated. Preprocessing of the reconstructed images and statistical analysis were performed using SPM2. Our findings show that intersubject anatomical differences can cause the minimum sample size to increase between 10 and 42% for posterior cingulate Cortex and between 40 and 80% for superior temporal cortex. Ideal scatter correction (ISC) allowed us to diminish the sample size up to 18% and fully 3D reconstruction reduced the minimum sample size between 8 and 33%. Detection sensitivity was higher for hypo-activation than for hyper-activation situations and higher for superior temporal cortex than for posterior cingulate cortex.

  4. System for recalculation and evaluation of dose to patients after anatomical variations in external radiotherapy treatments; Sistema para recalculo y evaluacion de dosis a pacientes tras variaciones anatomicas en tratamientos de radioterapia externa

    Energy Technology Data Exchange (ETDEWEB)

    Benito Bejarano, M. A.; Saez Beltran, F.

    2013-07-01

    In external beam radiation treatments due to changes in the anatomy of the patient (usually by loss or weight gain) repeating the simulation TAC may be necessary After a few weeks from the start of treatment, to assess the dosimetric impact . In this paper we use a module of multimodal fusion to record study original simulation with other obtained during treatment, calculate the variation of dosimetry with anatomical changes suffered by the patient during the same and, if necessary, adapt the plan treatment. (Author)

  5. Early fetal anatomical sonography.

    LENUS (Irish Health Repository)

    Donnelly, Jennifer C

    2012-10-01

    Over the past decade, prenatal screening and diagnosis has moved from the second into the first trimester, with aneuploidy screening becoming both feasible and effective. With vast improvements in ultrasound technology, sonologists can now image the fetus in greater detail at all gestational ages. In the hands of experienced sonographers, anatomic surveys between 11 and 14 weeks can be carried out with good visualisation rates of many structures. It is important to be familiar with the normal development of the embryo and fetus, and to be aware of the major anatomical landmarks whose absence or presence may be deemed normal or abnormal depending on the gestational age. Some structural abnormalities will nearly always be detected, some will never be and some are potentially detectable depending on a number of factors.

  6. Dopaminergic drug effects during reversal learning depend on anatomical connections between the orbitofrontal cortex and the amygdala.

    Directory of Open Access Journals (Sweden)

    Marieke E. van der Schaaf

    2013-08-01

    Full Text Available Dopamine in the striatum is known to be important for reversal learning. However, the striatum does not act in isolation and reversal learning is also well accepted to depend on the orbitofrontal cortex (OFC and the amygdala. Here we assessed whether dopaminergic drug effects on human striatal BOLD signalling during reversal learning is associated with anatomical connectivity in an orbitofrontal-limbic-striatal network, as measured with diffusion tensor imaging. By using a fibre-based approach, we demonstrate that dopaminergic drug effects on striatal BOLD signal varied as a function of fractional anisotropy (FA in a pathway connecting the OFC with the amygdala. Moreover, our experimental design allowed us to establish that these white-matter dependent drug effects were mediated via D2 receptors. Thus, white matter dependent effects of the D2 receptor agonist bromocriptine on striatal BOLD signal were abolished by co-administration with the D2 receptor antagonist sulpiride. These data provide fundamental insight into the mechanism of action of dopaminergic drug effects during reversal learning. In addition, they may have important clinical implications by suggesting that white matter integrity can help predict dopaminergic drug effects on brain function, ultimately contributing to individual tailoring of dopaminergic drug treatment strategies in psychiatry.

  7. Clinical Effect of Acute Complete Acromioclavicular Joint Dislocation Treated with Micro-Movable and Anatomical Acromioclavicular Plate

    Directory of Open Access Journals (Sweden)

    Qingjun Liu, Jianyun Miao, Bin Lin, Zhimin Guo

    2012-01-01

    Full Text Available Objectives: We evaluated the long-term clinical results of acute complete acromioclavicular dislocations treated with micro-movable and anatomical acromioclavicular plate.Methods: Open reduction and internal fixation was performed using the MAAP in 16 patients (10 males, 6 females; mean age 36 years; range16 to 63 years with acute complete acromioclavicular joint dislocation. Radiographic evaluations were routinely conducted every 3 weeks until 3 months postoperatively. The MAAP were removed under local anesthesia after 3 months postoperatively. We evaluated the functional results by using the constant scoring system and radiological results in the last follow-up time. The mean follow up was 26 months (range 16 to 38 months.Results: The mean Constant score was 94 (range, 78 to 100. The results were excellent in 12 patients (75.0%, good in 3 patients (18.8% and satisfactory in 1patient (6.2%. Three patients with scores of 80 to 90 had mild pain during activity, but have not affected the shoulder range of motion. One patient has both some pain and limited range of motion of shoulder joint. All patients but one have returned to their preoperative work without any limitations. Compared to the contralateral side, radiography showed anatomical reposition in the vertical plane in 14 cases, slight loss of reduction in 2 older patients.Conclusion: We recommend the MAAP fixation for surgical treatment of acute complete acromioclavicular joint dislocation as it could provide satisfactory shoulder functions and clinical results, with lower complication rate. However, it is necessary to continue to observe the clinical effects of this fixation technique.

  8. Anatomic Total Shoulder System

    Medline Plus

    Full Text Available GLOBAL AP ANATOMIC TOTAL SHOULDER SYSTEM METHODIST HOSPITAL PHILADELPHIA, PA April 17, 2008 00:00:10 ANNOUNCER: ... you'll be able to watch a live global AP anatomic total shoulder surgery from Methodist Hospital ...

  9. Anatomical connection strength predicts dopaminergic drug effects on fronto-striatal function

    OpenAIRE

    van Schouwenburg, Martine R.; Zwiers, Marcel P.; van der Schaaf, Marieke E.; Geurts, Dirk E M; Arnt F.A. Schellekens; Buitelaar, Jan K; Verkes, Robbert J.; Cools, Roshan

    2013-01-01

    Rationale The neurotransmitter dopamine plays a key role in cognitive functions that are associated with fronto-striatal circuitry and has been implicated in many neuropsychiatric disorders. However, there is a large variability in the direction and extent of dopaminergic drug effects across individuals. Objectives We investigated whether individual differences in dopaminergic drug effects on human fronto-striatal functioning are associated with individual differences in white matter tracts. ...

  10. Anatomical, morphological, and phytochemical effects of inoculation with plant growth- promoting rhizobacteria on peppermint (Mentha piperita).

    Science.gov (United States)

    del Rosario Cappellari, Lorena; Santoro, Maricel Valeria; Reinoso, Herminda; Travaglia, Claudia; Giordano, Walter; Banchio, Erika

    2015-02-01

    Plant growth-promoting rhizobacteria (PGPR) generally exert their effects through enhancement of plant nutrient status and/or phytohormone production. The effects of PGPR on aromatic plant species are poorly known. We measured plant growth parameters, chlorophyll content, trichome density, stomatal density, and levels of secondary metabolites in peppermint (Mentha piperita) seedlings inoculated with PGPR strains Bacillus subtilis GB03, Pseudomonas fluorescens WCS417r, P. putida SJ04, or a combination of WCS417r + SJ04. The treated plants, in comparison with controls, showed increases in shoot biomass, root biomass, leaf area, node number, trichome density, and stomatal density, and marked qualitative and quantitative changes in monoterpene content. Improved knowledge of the factors that control or affect biosynthesis of secondary metabolites and monoterpene accumulation will lead to strategies for improved cultivation and productivity of aromatic plants and other agricultural crops without the use of chemical fertilizers or pesticides.

  11. Effects of Aging and Anatomic Location on Gene Expression in Human Retina

    Directory of Open Access Journals (Sweden)

    Hui eCai

    2012-05-01

    Full Text Available Objective: To determine the effects of age and topographic location on gene expression in human neural retina.Methods: Macular and peripheral neural retina RNA were isolated from human donor eyes for DNA microarray and quantitative RT-PCR analyses.Results: Total RNA integrity from human donors was preserved. Hierarchical clustering analysis demonstrates that the gene expression profiles of young, old, macula and peripheral retina cluster into four distinct groups. Genes which are highly expressed in macular, peripheral, young or old retina were identified, including inhibitors of Wnt Signaling Pathway (DKK1, FZD10 and SFRP2 which are preferably expressed in the periphery. Conclusions: The transcriptome of the human retina is affected by age and topographic location. Wnt pathway inhibitors in the periphery may maintain peripheral retinal cells in an undifferentiated state. Understanding the effects of age and topographic location on gene expression may lead to the development of new therapeutic interventions for age-related eye diseases.

  12. Effects of age, gender, BMI, and anatomical site on skin thickness in children and adults with diabetes.

    Directory of Open Access Journals (Sweden)

    José G B Derraik

    Full Text Available OBJECTIVE: We aimed to assess the effects of age, sex, body mass index (BMI, and anatomical site on skin thickness in children and adults with diabetes. METHODS: We studied 103 otherwise healthy children and adolescents with type 1 diabetes aged 5-19 years, and 140 adults with type 1 and type 2 diabetes aged 20-85 years. The thicknesses of both the dermis and subcutis were assessed using ultrasound with a linear array transducer, on abdominal and thigh skin. RESULTS: There was an age-related thickening of both dermis (p<0.0001 and subcutis (p = 0.013 in children and adolescents. Girls displayed a substantial pubertal increase in subcutis of the thigh (+54%; p = 0.048 and abdomen (+68%; p = 0.009. Adults showed an age-related decrease in dermal (p = 0.021 and subcutis (p = 0.009 thicknesses. Pubertal girls had a thicker subcutis than pubertal boys in both thigh (16.7 vs 7.5 mm; p<0.0001 and abdomen (16.7 vs 8.8 mm; p<0.0001. Men had greater thigh dermal thickness than women (1.89 vs 1.65 mm; p = 0.003, while the subcutis was thicker in women in thigh (21.3 vs 17.9 mm; p = 0.012 and abdomen (17.7 vs 9.8 mm; p<0.0001. In boys, men, and women, both dermis and subcutis were thicker on the abdomen compared to thigh; in girls this was only so for dermal thickness. In both children and adults, the skin (dermis and subcutis became steadily thicker with increasing BMI (p<0.0001. CONCLUSIONS: Skin thickness is affected by age, pubertal status, gender, BMI, and anatomical site. Such differences may be important when considering appropriate sites for dermal/subcutaneous injections and other transdermal delivery systems.

  13. The importance of investigation of anatomic variations in the ethmoid cells by computerized tomography in the planning of endoscopic nasal surgery; A importancia da investigacao de variacoes anatomicas das celulas etmoidais atraves da tomografia computadorizada no planejamento da cirurgia endoscopica nasal

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz, Cristiane Regina; Wafae, Nader; Nascimento, Sergio Ricardo Rios; Camelo, Julio Cesar; Maciel, Luana Teixeira; Consolari, Mario Agostinho Severo [Centro Universitario Sao Camilo, Sao Paulo, SP (Brazil)], e-mail: crisruiz@saocamilo-sp.br, e-mail: riosnascimento@uol.com.br

    2009-01-15

    The ethmoidal cells comprise many cavities that show many anatomical variations. Some of these variations deserve special attention when associated with sinusitis and the need of surgery. Computed tomography, considered a gold standard on the pathological investigation of the nasal cavity and the anatomic description of paranasal sinus, offers information about these cells, essential to minimize the surgical risks. The authors present a bibliographic revision of the importance of computed tomography on the investigation of anatomic variations of ethmoid cells. Not recurrent cells in all individuals, like Haller's cells, Onodi's cells and pneumatization of agger nasi, will do the endoscopic approach with precaution. The ethmoidal roof evaluation will result in more safety on the upper limits of the nasal cavity. The size and pneumatization level of ethmoidal bulla, ethmoidal crest, and middle nasal concha are important on the evaluation of the endoscopic accesses and the gravity of the stroked pathology and even diagnose your origin. (author)

  14. Population effects of increased climate variation

    OpenAIRE

    Drake, John M.

    2005-01-01

    Global circulation models predict and numerous observations confirm that anthropogenic climate change has altered high-frequency climate variability. However, it is not yet well understood how changing patterns of environmental variation will affect wildlife population dynamics and other ecological processes. Theory predicts that a population's long-run growth rate is diminished and the chance of population extinction is increased as environmental variation increases. This results from the fa...

  15. Effect of Anatomically Realistic Full-Head Model on Activation of Cortical Neurons in Subdural Cortical Stimulation—A Computational Study

    Science.gov (United States)

    Seo, Hyeon; Kim, Donghyeon; Jun, Sung Chan

    2016-06-01

    Electrical brain stimulation (EBS) is an emerging therapy for the treatment of neurological disorders, and computational modeling studies of EBS have been used to determine the optimal parameters for highly cost-effective electrotherapy. Recent notable growth in computing capability has enabled researchers to consider an anatomically realistic head model that represents the full head and complex geometry of the brain rather than the previous simplified partial head model (extruded slab) that represents only the precentral gyrus. In this work, subdural cortical stimulation (SuCS) was found to offer a better understanding of the differential activation of cortical neurons in the anatomically realistic full-head model than in the simplified partial-head models. We observed that layer 3 pyramidal neurons had comparable stimulation thresholds in both head models, while layer 5 pyramidal neurons showed a notable discrepancy between the models; in particular, layer 5 pyramidal neurons demonstrated asymmetry in the thresholds and action potential initiation sites in the anatomically realistic full-head model. Overall, the anatomically realistic full-head model may offer a better understanding of layer 5 pyramidal neuronal responses. Accordingly, the effects of using the realistic full-head model in SuCS are compelling in computational modeling studies, even though this modeling requires substantially more effort.

  16. 腕管内正中神经变异的声像图表现及其临床意义%Sonographic appearance and clinical significance of anatomic variation of carpal tunnel median nerve

    Institute of Scientific and Technical Information of China (English)

    傅强; 崔立刚; 李志强; 王金锐; 陈文; 贾建文

    2012-01-01

    Objective To investigate the incidence,sonographic appearance of the anatomic variation of carpal tunnel median nerve and its accompanying structures in healthy volunteers and explore the value of this variation in carpal tunnel syndrome.Methods A total of 360 hands of 180 healthy volunteers were included in the study.The full course of the median nerve in the forearm and carpal tunnel was examined with high-frequency ultrasound.The median nerve was first located in cross section at wrist and then with continuous cross-sectional scanning to observe the the full course of the median nerve in the forearm and carpal tunnel with high-frequency ultrasound.Results Anatomic variation of carpal tunnel median nerve and its accompanying structures were observed:① High division median nerve were found in 2 wrists (0.56 %) ;②Bifid median nerve were found in 17 wrists (4.72%) ;③Persistent median artery were found in 22 wrists (6.11%),and 2 wrists (0.56%) were also found accompanied vein.Aanatomic variation of carpal tunnel median nerve accompanied with persistent median artery were observed in 16 wrists (4.44 %).Conclusions High-frequency ultrasound was sensitive to diagnose the anatomic variation of carpal tunnel median nerve and its accompanying structures.Recognition of these variations can help us to make correct diagnosis of carpal tunnel syndrome.%目的 探讨腕管正中神经及伴行结构变异在人群中的发生率、超声表现及其在腕管综合征诊断中的意义.方法 对180位健康志愿者的360只手腕部腕管结构及前臂进行高频超声检查.检查前臂和腕部正中神经走行,先进行腕管结构的横断面扫查,确认正中神经位置后,采用连续横断面扫查法向近端前臂进行动态观察并适当结合纵断面扫查,记录图像资料.结果 腕管正中神经及伴行结构变异:①正中神经高位分叉2例(0.56%);②正中神经裂17例(4.72%);③腕部正中神

  17. The effect of model errors in variational assimilation

    OpenAIRE

    Wergen, Werner

    2011-01-01

    A linearized, one-dimensional shallow water model is used to investigate the effect of model errors in four-dimensional variational assimilation. A suitable initialization scheme for variational assimilation is proposed. Introducing deliberate phase speed errors in the model, the results from variational assimilation are compared to standard analysis/forecast cycle experiments. While the latter draws to the data and reflects the model errors only in the datavoid areas, variational assimilatio...

  18. Anatomical study of the effects of five surgical maneuvers on palate movement.

    Science.gov (United States)

    Mendonca, Derick A; Patel, Kamlesh B; Skolnick, Gary B; Woo, Albert S

    2014-06-01

    The anatomy of the palate has been extensively described, with a predominant focus on palatal musculature. There are no biomechanical studies investigating the effects of surgical maneuvers on the palate to aid cleft closure. This study aims to describe the soft tissue attachments at different zones and quantify the movement following their release. Fourteen adult cadaver heads were dissected. The palates were split in the midline and five maneuvers described: Step 1, over the hard palate; Step 2, around the greater palatine pedicle; Step 3, over the palatine aponeurosis; Step 4, over the hamulus; and Step 5, resulting in a hamulus fracture. The movements across the midline at the posterior nasal spine following each maneuver were measured. The age range of the 14 heads was between 60 -75 years. Completion of steps 1 and 2 over the hard palate obtained a mean release of 2.6 and 2.0 mm, respectively. The largest movements occurred at Step 3 (5.7 mm) and Step 4 (3.5 mm), after releasing attachments at the posterior hard palate and palatine aponeurosis. Steps 3 and 4 dissections exhibited cumulative release, with a maximum movement with Step 3 (p palate junction. Additional dissection along the hamulus (without fracture) added significantly to this release.

  19. TOPICAL REVIEW: Anatomical imaging for radiotherapy

    Science.gov (United States)

    Evans, Philip M.

    2008-06-01

    scans is taken on different days. Both allow planning to account for variability intrinsic to the patient. Treatment verification has been carried out using a variety of technologies including: MV portal imaging, kV portal/fluoroscopy, MVCT, conebeam kVCT, ultrasound and optical surface imaging. The various methods have their pros and cons. The four x-ray methods involve an extra radiation dose to normal tissue. The portal methods may not generally be used to visualize soft tissue, consequently they are often used in conjunction with implanted fiducial markers. The two CT-based methods allow measurement of inter-fraction variation only. Ultrasound allows soft-tissue measurement with zero dose but requires skilled interpretation, and there is evidence of systematic differences between ultrasound and other data sources, perhaps due to the effects of the probe pressure. Optical imaging also involves zero dose but requires good correlation between the target and the external measurement and thus is often used in conjunction with an x-ray method. The use of anatomical imaging in radiotherapy allows treatment uncertainties to be determined. These include errors between the mean position at treatment and that at planning (the systematic error) and the day-to-day variation in treatment set-up (the random error). Positional variations may also be categorized in terms of inter- and intra-fraction errors. Various empirical treatment margin formulae and intervention approaches exist to determine the optimum strategies for treatment in the presence of these known errors. Other methods exist to try to minimize error margins drastically including the currently available breath-hold techniques and the tracking methods which are largely in development. This paper will review anatomical imaging techniques in radiotherapy and how they are used to boost the therapeutic benefit of the treatment.

  20. PREVALENCE OF ANATOMICAL VARIATION OF THE SIXTH CERVICAL VERTEBRA AND ASSOCIATION WITH VERTEBRAL CANAL STENOSIS AND ARTICULAR PROCESS OSTEOARTHRITIS IN THE HORSE.

    Science.gov (United States)

    DeRouen, Anthony; Spriet, Mathieu; Aleman, Monica

    2016-05-01

    The sixth cervical vertebra (C6) has unique morphology due to a ventral extension from the transverse process known as the ventral lamina. Little information was found regarding the prevalence and clinical relevance of morphologic variations. Aims of this observational, retrospective study were to characterize C6 morphologic variations in a large sample of horses. Cervical radiographic studies of 100 horses were retrieved. Data recorded were signalment, clinical history, morphology of the C6 ventral lamina, presence of articular process osteoarthritis, and presence of static vertebral canal stenosis. Morphologic variations were found in C6 vertebrae for 24/100 horses, with symmetric absence of the ventral lamina in nine horses and asymmetric absence in 15. Anomalous C6 vertebrae were more common in Warmbloods, with 19/55 Warmbloods in the population being affected (P = 0.006). No association was found with sex. There was no significant difference in the mean of the intravertebral sagittal ratios between horses with normal or anomalous C6 vertebrae; however there was a significantly greater proportion of horses with anomalous C6 vertebrae that had an intravertebral sagittal ratio of less than 0.5 at C6 (P = 0.047). There was no association between the morphology of C6 and articular process osteoarthritis. Anomalous C6 vertebrae in our population were associated with a higher likelihood of cervical pain (P = 0.013). Authors propose that morphologic variations in the C6 ventral laminae could be linked to other developmental abnormalities such as vertebral canal stenosis, might affect regional biomechanics and should therefore be considered clinically relevant in horses. Future, controlled prospective studies are needed to test this theory. PMID:26915973

  1. Effect of the anatomical site on telomere length and pref-1 gene expression in bovine adipose tissues

    International Nuclear Information System (INIS)

    Adipose tissue growth is associated with preadipocyte proliferation and differentiation. Telomere length is a biological marker for cell proliferation. Preadipocyte factor-1 (pref-1) is specifically expressed in preadipocytes and acts as a molecular gatekeeper of adipogenesis. In the present study, we investigated the fat depot-specific differences in telomere length and pref-1 gene expression in various anatomical sites (subcutaneous, intramuscular and visceral) of fattening Wagyu cattle. Visceral adipose tissue expressed higher pref-1 mRNA than did subcutaneous and intramuscular adipose tissues. The telomere length in visceral adipose tissue tended to be longer than that of subcutaneous and intramuscular adipose tissues. The telomere length of adipose tissue was not associated with adipocyte size from three anatomical sites. No significant correlation was found between the pref-1 mRNA level and the subcutaneous adipocyte size. In contrast, the pref-1 mRNA level was negatively correlated with the intramuscular and visceral adipocyte size. These results suggest that anatomical sites of adipose tissue affect the telomere length and expression pattern of the pref-1 gene in a fat depot-specific manner. - Highlights: • Visceral adipose tissue express higher pref-1 mRNA than other anatomical sites. • Telomere length in visceral adipose tissue is longer than other anatomical sites. • Telomere length of adipose tissue is not associated with adipocyte size. • Pref-1 mRNA is negatively correlated with intramuscular and visceral adipocyte size

  2. Effect of the anatomical site on telomere length and pref-1 gene expression in bovine adipose tissues

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Tomoya, E-mail: toyamada@affrc.go.jp; Higuchi, Mikito; Nakanishi, Naoto

    2015-08-07

    Adipose tissue growth is associated with preadipocyte proliferation and differentiation. Telomere length is a biological marker for cell proliferation. Preadipocyte factor-1 (pref-1) is specifically expressed in preadipocytes and acts as a molecular gatekeeper of adipogenesis. In the present study, we investigated the fat depot-specific differences in telomere length and pref-1 gene expression in various anatomical sites (subcutaneous, intramuscular and visceral) of fattening Wagyu cattle. Visceral adipose tissue expressed higher pref-1 mRNA than did subcutaneous and intramuscular adipose tissues. The telomere length in visceral adipose tissue tended to be longer than that of subcutaneous and intramuscular adipose tissues. The telomere length of adipose tissue was not associated with adipocyte size from three anatomical sites. No significant correlation was found between the pref-1 mRNA level and the subcutaneous adipocyte size. In contrast, the pref-1 mRNA level was negatively correlated with the intramuscular and visceral adipocyte size. These results suggest that anatomical sites of adipose tissue affect the telomere length and expression pattern of the pref-1 gene in a fat depot-specific manner. - Highlights: • Visceral adipose tissue express higher pref-1 mRNA than other anatomical sites. • Telomere length in visceral adipose tissue is longer than other anatomical sites. • Telomere length of adipose tissue is not associated with adipocyte size. • Pref-1 mRNA is negatively correlated with intramuscular and visceral adipocyte size.

  3. Climate variations and the enhanced greenhouse effect

    Energy Technology Data Exchange (ETDEWEB)

    Karlen, W. [Stockholm Univ. (Sweden). Dept. of Physical Geography

    1998-06-01

    Changes in the size of glaciers, in the altitude of the alpine tree-limit, and variation in the width of tree-rings during the Holocene clearly indicate that the average Scandinavian summer temperature has fluctuated. During warm periods it has been about 2 deg C warmer than at present; during cold periods it has been almost as cold as it was during the coldest decades of the previous centuries. Superimposed on these long-term variations, which have lasted from 100 to 200 years, are short fluctuations in temperature. The Scandinavian chronology, which is based on glacier and alpine tree-limit fluctuations as well as on dendrochronology, is well correlated with the changes in climate, which studies of ice cores from central Greenland have revealed. It is therefore believed that the Scandinavian climate chronology depicts conditions typical of a large area. The Scandinavian record is compared with data concerning solar irradiation variations estimated as {sup 14}C anomalies obtained from tree-rings. A correlation between major changes in climate and variations in solar irradiation points to a solar forcing of the climate. This means that there is no evidence of a human influence on climate so far Special issue. Research for mountain area development: Europe. 64 refs, 3 figs

  4. Femoroacetabular impingement and the cam-effect. A MRI-based quantitative anatomical study of the femoral head-neck offset.

    Science.gov (United States)

    Ito, K; Minka, M A; Leunig, M; Werlen, S; Ganz, R

    2001-03-01

    We have observed damage to the labrum as a result of repetitive acetabular impingement in non-dysplastic hips, in which the femoral neck appears to abut against the acetabular labrum and a non-spherical femoral head to press against the labrum and adjacent cartilage. In both mechanisms anatomical variations of the proximal femur may be a factor. We have measured the orientation of the femoral neck and the offset of the head at various circumferential positions, using MRI data from volunteers with no osteoarthritic changes on standard radiographs. Compared with the control subjects, paired for gender and age, patients showed a significant reduction in mean femoral anteversion and mean head-neck offset on the anterior aspect of the neck. This was consistent with the site of symptomatic impingement in flexion and internal rotation, and with lesions of the adjacent rim. Furthermore, when stratified for gender and age, and compared with the control group, the mean femoral head-neck offset was significantly reduced in the lateral-to-anterior aspect of the neck for young men, and in the anterolateral-to-anterior aspect of the neck for older women. For patients suspected of having impingement of the rim, anatomical variations in the proximal femur should be considered as a possible cause.

  5. Severe Feeding Problems Secondary to Anatomical Disorders: Effectiveness of Behavioural Treatment in Three School-Aged Children

    Science.gov (United States)

    de Moor, Jan; Didden, Robert; Tolboom, Jules

    2005-01-01

    In the present study, behavioural treatment is described of three school-aged children with severe feeding problems caused by (surgically corrected) anatomical disorders of the digestive system. Two children showed food refusal and were tube-fed whereas the third child showed extreme food selectivity. During treatment, shaping, (non)verbal…

  6. 儿童枕骨鳞部正常解剖、解剖变异及骨折的三维CT特征%Three-dimensional CT features of occipital squama normal anatomy, anatomic variations and fractures

    Institute of Scientific and Technical Information of China (English)

    刘俊刚; 李欣; 王春祥; 张琳; 国婉华

    2013-01-01

    目的 探讨儿童枕骨鳞部正常解剖、解剖变异及骨折的三维CT特征.方法 回顾性分析589例患儿三维CT图像特征,所有图像均进行MIP、VR三维立体图像重组,分别观察正常枕骨鳞部的解剖、变异及骨折,总结其各自的部位、形态及其走行等鉴别诊断特征.结果 433例(75.2%)患儿未见颅缝变异,其中154例与成人期枕骨鳞部解剖特征相同,279例可见后枕内联合,37例可见Kerckring-上枕骨软骨联合.排除近期外伤者,共113例(19.1%)发生解剖变异,包括未贯通缝和贯通缝,其存在部位遵循骨化发生规律.未贯通缝包括假缝23例,上正中裂19例,上枕骨正中裂4例.贯通缝包括顶间骨变异54例,缝间骨23例,副骨7例.33例同时存在两种或两种以上变异.34例(5.6%)见枕骨鳞部骨折,包括线样骨折27例,粉碎性骨折3例,凹陷骨折1例,颅缝分离3例,另外尚见3例变异合并骨折者.骨折线锐利,常为线样或折线样,走行不受骨化发生限制.结论 儿童期枕骨鳞部正常解剖、解剖变异及骨折有其各自不同的三维CT特征,正确认识对准确诊断至关重要.%Objective To evaluate 3D CT features of normal anatomy,anatomic variations and fractures of occipital squama.Methods The 3D CT features on MIP,VR images were analyzed retrospectively in 589 pediatric cases.The normal anatomy,anatomic variations and fractures of occipital squama were observed respectively,and the differential diagnostic features including the individual location,appearance and extension were analyzed.Results Four hundred and thirty-three patients (75.2%) showed normal anatomy,including 154 patients with adult occipital anatomical features,279 patients with posterior intraoccipital synchondrosis,and 37 patients with Kerckring-supraoccipital synchondrosis.When cases with recent trauma history were excluded,113 patients (19.1%) showed anatomic variants,including unpenetrating sutures and penetrating sutures

  7. Microstructure and Anatomical Characteristics of Daemonorops margaritae

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Daemonorops margaritae is among the most important commercial rattan in South China. Its microstructure and basic anatomical characteristics as well as variation were investigated. Results show that: 1)The variation along the height is small, while the variation along the radial direction is significant; 2) The fibre length, fibre ratio and distribution density of the vascular bundles in the cross section decrease from cortex to core, while the fibre width, vessel element length and width, parenchyma ratio,...

  8. Variações anatômicas e sinusopatias: estudo por tomografia computadorizada Anatomical variations and sinusitis: a computed tomographic study

    Directory of Open Access Journals (Sweden)

    Marcio M. Kinsui

    2002-10-01

    Full Text Available Introdução: A tomografia computadorizada tem sido cada vez mais utilizada para a identificação e avaliação das variações anatômicas das cavidades nasais que podem levar às sinusites. Objetivo: Avaliar, por meio da tomografia computadorizada, a incidência de espessamento mucoso nos seios paranasais de pacientes com sintomas de sinusite e a correlação entre sinusopatias e presença de célula de Haller, concha média bolhosa e desvio de septo nasal localizado no meato médio. Forma de Estudo: Clínico retrospectivo. Material e Método: Foram avaliadas retrospectivamente 150 tomografias computadorizadas de seios paranasais de pacientes com idade igual ou superior a 13 anos, realizadas no Departamento de Diagnóstico por Imagem da Universidade Federal de São Paulo - Escola Paulista de Medicina, no período de julho de 1999 a outubro de 2001. Foram excluídos os exames de pacientes com pós-operatório de cirurgias de seios paranasais e de base de crânio, além dos portadores de lesões tumorais envolvendo estas regiões. Resultados: 70% dos pacientes apresentavam espessamento mucoso em pelo menos um dos seios paranasais. Observou-se a freqüência de 52,7% de sinusopatia maxilar, 28,0% de etmoidal, 13,0% de esfenoidal e 8,3% de frontal. Concha média bolhosa foi encontrada em 33,3% das cavidades nasais, desvio de septo nasal localizado no meato médio em 23,3% e célula de Haller em 9,3%. Conclusões: Os seios paranasais mais freqüentemente acometidos foram, em ordem decrescente: maxilar, etmoidal, esfenoidal e frontal. Não foi observado correlação entre sinusopatias e presença de célula de Haller, concha média bolhosa e desvio de septo nasal localizado no meato médio.Introduction: Computed tomography has been increasingly used both to identify and to evaluate anatomy variations of nasal cavities that can lead to the development of sinusitis. Purpose: The purpose of the present study is to determine the incidence of mucosal

  9. Effect of the anatomical site on telomere length and pref-1 gene expression in bovine adipose tissues.

    Science.gov (United States)

    Yamada, Tomoya; Higuchi, Mikito; Nakanishi, Naoto

    2015-08-01

    Adipose tissue growth is associated with preadipocyte proliferation and differentiation. Telomere length is a biological marker for cell proliferation. Preadipocyte factor-1 (pref-1) is specifically expressed in preadipocytes and acts as a molecular gatekeeper of adipogenesis. In the present study, we investigated the fat depot-specific differences in telomere length and pref-1 gene expression in various anatomical sites (subcutaneous, intramuscular and visceral) of fattening Wagyu cattle. Visceral adipose tissue expressed higher pref-1 mRNA than did subcutaneous and intramuscular adipose tissues. The telomere length in visceral adipose tissue tended to be longer than that of subcutaneous and intramuscular adipose tissues. The telomere length of adipose tissue was not associated with adipocyte size from three anatomical sites. No significant correlation was found between the pref-1 mRNA level and the subcutaneous adipocyte size. In contrast, the pref-1 mRNA level was negatively correlated with the intramuscular and visceral adipocyte size. These results suggest that anatomical sites of adipose tissue affect the telomere length and expression pattern of the pref-1 gene in a fat depot-specific manner.

  10. Evaluation of Anatomical and Functional Hip Joint Center Methods: The Effects of Activity Type, Gender, and Proximal Reference Segment.

    Science.gov (United States)

    McGibbon, C A; Fowler, J; Chase, S; Steeves, K; Landry, J; Mohamed, A

    2016-01-01

    Accurate hip joint center (HJC) location is critical when studying hip joint biomechanics. The HJC is often determined from anatomical methods, but functional methods are becoming increasingly popular. Several studies have examined these methods using simulations and in vivo gait data, but none has studied high-range of motion activities, such a chair rise, nor has HJC prediction been compared between males and females. Furthermore, anterior superior iliac spine (ASIS) marker visibility during chair rise can be problematic, requiring a sacral cluster as an alternative proximal segment; but functional HJC has not been explored using this approach. For this study, the quality of HJC measurement was based on the joint gap error (JGE), which is the difference in global HJC between proximal and distal reference segments. The aims of the present study were to: (1) determine if JGE varies between pelvic and sacral referenced HJC for functional and anatomical methods, (2) investigate which functional calibration motion results in the lowest JGE and if the JGE varies depending on movement type (gait versus chair rise) and gender, and (3) assess whether the functional HJC calibration results in lower JGE than commonly used anatomical approaches and if it varies with movement type and gender. Data were collected on 39 healthy adults (19 males and 20 females) aged 14-50 yr old. Participants performed four hip "calibration" tests (arc, cross, star, and star-arc), as well as gait and chair rise (activities of daily living (ADL)). Two common anatomical methods were used to estimate HJC and were compared to HJC computed using a published functional method with the calibration motions above, when using pelvis or sacral cluster as the proximal reference. For ADL trials, functional methods resulted in lower JGE (12-19 mm) compared to anatomical methods (13-34 mm). It was also found that women had significantly higher JGE compared to men and JGE was significantly higher for

  11. Anatomic Total Shoulder System

    Medline Plus

    Full Text Available GLOBAL AP ANATOMIC TOTAL SHOULDER SYSTEM METHODIST HOSPITAL PHILADELPHIA, PA April 17, 2008 00:00:10 ANNOUNCER: DePuy Orthopedics is continually advancing the standard of orthopedic patient care. In a few ...

  12. Anatomic Total Shoulder System

    Medline Plus

    Full Text Available ... to a patient's unique anatomical makeup. Dr. Gerald R. Williams, Jr., a shoulder specialist from the Rothman ... That might help. Could you raise the O.R. table, please? 00:28:35 WOMAN: Can you ...

  13. Anatomic Total Shoulder System

    Medline Plus

    Full Text Available GLOBAL AP ANATOMIC TOTAL SHOULDER SYSTEM METHODIST HOSPITAL PHILADELPHIA, PA April 17, 2008 00:00:10 ANNOUNCER: DePuy Orthopedics is continually advancing the standard of orthopedic patient ...

  14. Study on the travelling and anatomical variations of basilar artery via VCTDSA%基底动脉走行和变异的容积CT数字减影血管成像研究

    Institute of Scientific and Technical Information of China (English)

    唐贵超; 陈莉; 吕发金

    2013-01-01

    Objective To investigate the anatomical variations and travelling of basilar artery via volume computed tomography digital subtraction angiography (VCTDSA) and to investigate the relationship between the basilar artery bending and the development of intracranial segment of vertebral artery.Methods A total of 110 normal subjects underwent cerebral and cervical vessel VCTDSA were involved in the present study,and the images of basilar arteries were reconstructed by VR images.The development of vertebral artery,window variation and tortuosity of basilar artery,as well as the diameter and length of basilar artery were measured.The correlation between development of vertebral artery and tortuosity of basilar artery were analyzed.Results (1)In the 110cases,the rate of hypoplastic vertebral artery,tortuosity and window variation of basilar artery were 17.27% (19/110),22.73%(25/110) and 2.73%(3/110),respectively.(2)The average length and diameter of basilar artery were(28.25±3.88)mm and (3.86±0.54)mm,respectively.(3)The tortuosity and window variation of basilar artery showed positive correlation with the development of intracranial segment of vertebral artery(P<0.01,r=0.52).Conclusion VCTDSA could clearly show the anatomy and variability of basilar artery,and its anatomic valuable could act as the reference for the diagnosis of cerebral diseases in clinic.The hypoplasia of intracranial segment of vertebral artery could be correlate with tortuosity of basilar artery.%目的 运用容积CT数字减影血管成像(VCTDSA)研究基底动脉走行和变异,探讨基底动脉迂曲与椎动脉颅内段发育不良之间的关系.方法 观测2010年1月至2011年12月在重庆医科大学附属第一医院行VCTDSA检查、非脑卒中患者且头部或头颈VCTDSA检查未见病变者110例,在容积再现(VR)图像上观察双侧椎动脉颅内段发育情况、基底动脉有无迂曲、是否存在窗型变异,并分别测量基底动脉的长度与管径,同时

  15. Antidepressant-Like Behavioral, Anatomical, and Biochemical Effects of Petroleum Ether Extract from Maca (Lepidium meyenii) in Mice Exposed to Chronic Unpredictable Mild Stress

    OpenAIRE

    Ai, Zhong; Cheng, Ai-Fang; Yu, Yuan-Tao; Yu, Long-Jiang; Jin, Wenwen

    2014-01-01

    Maca has been consumed as a medical food in Peru for thousands of years, and exerts anxiolytic and antidepressant effects. Our present study aimed to evaluate the behavior and anatomical and biochemical effects of petroleum ether extract from maca (ME) in the chronic unpredictable mild stress (CUMS) model of depression in mice. Three different doses of maca extract (125, 250, and 500 mg/kg) were orally administrated in the six-week CUMS procedure. Fluoxetine (10 mg/kg) was used as a positive ...

  16. Estudo anatômico do terço proximal do fêmur: impacto femoroacetabular e o efeito cam Anatomic study of the proximal third of the femur: femoroacetabular impact and the cam effect

    Directory of Open Access Journals (Sweden)

    Pedro José Labronici

    2009-04-01

    Full Text Available OBJETIVO: Analisar as varia��ões anatômicas da extremidade proximal do fêmur que pudessem desenvolver o impacto femoroacetabular. MÉTODOS: Foram utilizados 199 espécimes anatômicos de fêmures esqueleticamente maduros. Os fêmures foram medidos para determinar o ângulo da anteversão do colo femoral, ângulo cervicodiafisário, esfericidade da cabeça femoral em ântero-posterior e súpero-inferior, ângulo entre a epífise e o colo femoral anterior, ângulo entre a epífise e o colo em perfil, distância em ântero-posterior a 5mm da junção cabeça e colo e distância em ântero-posterior da base do colo. RESULTADOS: Observou-se que o subgrupo com impacto apresentou diâmetro da junção a 5mm (p = 0,0001 e cam-cabeça (% (p = 0,0001 significativamente maiores e base-cam (% (p = 0,0001 significativamente menor que o subgrupo sem impacto. Identificou-se que cam-cabeça (% > 80 e base-cam (% OBJECTIVE: to analyze anatomical variations of the proximal end of femur that could cause a femoroacetabular impact. METHODS: 199 skeletically mature anatomical specimens of femurs were used. The femurs were measured in order to determine the anteversion angle of the femoral neck, neckshaft angle, sphericity of the femoral head at anteroposterior and superoinferior, angle between epiphysis and the anterior femoral neck, angle between epiphysis and the neck at lateral plane, anteroposterior distance at 5mm of the head and neck junction and anteroposterior distance of the neck base. RESULTS: we found that the impact subgroup presented a significantly larger junction diameter of 5mm (p = 0.0001 and cam-head (% (p= 0.0001, while base-cam (% (p = 0.0001 showed a significantly smaller diameter than the subgroup without impact. It was identified that cam-head (% > 80 e base-cam (% < 73 were identified as the optimal impact points. CONCLUSION: our study showed that the effect cam, caused by anatomical variations of the proximal femoral end focused the

  17. Determinants of Temporal Variations in Advertising Effectiveness

    OpenAIRE

    Chung, Chanjin; Kaiser, Harry M.

    1998-01-01

    This article develops a varying-parameter advertising model which specifies advertising parameters as a function of variables representing advertising strategies and market environments to explain the varying nature of the advertising responses. Unlike prior models, this model allows researchers to examine the sources of change in advertising effectiveness over time. The model is applied to the New York City fluid milk market for the period from January 1986 through June 1995. Results indicat...

  18. Effects of Zonal Wind on Stratospheric Ozone Variations over Nigeria

    Science.gov (United States)

    Chidinma Okoro, Eucharia,

    2016-07-01

    The effects of zonal wind on stratospheric ozone variation over Nigeria have been studied. The areas covered in this study include; Maiduguri, Ikeja, Port-Harcourt, Calabar, Makurdi, Ilorin, Akure, Yola, Minna, Jos, Kano and Enugu in Nigeria, from 1986 to 2008. Zonal wind was computed from the iso-velocity map employing MATLAB software. The mean monthly variations of AAM and LOD at pressure levels of 20, 30 and 50 mb in the atmosphere depict a trend of maximum amplitude between April and September, and minimum amplitude between December and March. The trend observed in seasonal variation of O3 column data in the low latitude had maximum amount from May through August and minimum values from December through February. The mean monthly maximum O3 concentrations was found to be 284.70 Du (Kano) occurring in May 1989 while, an average monthly minimum O3 concentration was found to be 235.60 Du (Port-Harcourt and Calabar) occurring in January 1998. It has been established in this study that, the variation in atmospheric angular momentum (AAM) caused by variation of the universal time or length of day (LOD) transfer ozone (O3) by means of zonal wind from the upper troposphere to the lower stratosphere in the stations understudy. The strong effect of the pressure levels of the atmosphere on O3 variation could be attributed to its effect on the AAM and LOD. Variation in the LOD is significant in the tropics, suggesting that, the effects of the extra-tropical suction pump (ETSP) action is not the only driver responsible for O3 transportation from the tropics to extra-tropical zones. Consequently, these findings lead to a deduction that weather pattern alteration observed due to these changes could lead to climate change. Keywords: ozone variations; dynamical processes; harmattan wind; ETSP; and climatic variability

  19. Ecophysiological and anatomical mechanisms behind the nurse effect: which are more important? A multivariate approach for cactus seedlings.

    Directory of Open Access Journals (Sweden)

    Pablo Delgado-Sánchez

    Full Text Available BACKGROUND: Cacti establish mostly occurs under the canopy of nurse plants which provide a less stressful micro-environment, although mechanisms underlying this process are unknown. The impact of the combination of light and watering treatments on Opuntia streptacantha (Cactaceae seedlings was examined. METHODS/PRINCIPAL FINDINGS: Ecophysiological [titratable acidity, osmotic potential ('solute potential', Ψs , relative growth rate (RGR and their components (NAR, SLA, and LWR], anatomical (chloroplast density, chloroplast frequency, and cell area, and environmental [photosynthetic photon flux density (PPFD and air temperature] sets of variables were analyzed, assessing relationships between them and measuring the intensity of the relationships. Three harvests were carried out at days 15, 30, and 45. Ψs and acidity content were the most important responses for seedling establishment. The main anatomical and environmental variables were chloroplast density and water availability, respectively. Opuntia streptacantha seedlings establish better in the shade-watering treatment, due to higher Ψs and acidity, unaffected chloroplasts, and lower PPFD. In addition, the chloroplasts of cells under high-light and non-watering treatment were clumped closer to the center of the cytosol than those under shade-drought, to avoid photoinhibition and/or to better distribute or utilize the penetrating light in the green plant tissue. CONCLUSIONS: Opuntia seedlings grow better under the shade, although they can tolerate drought in open spaces by increasing and moving chloroplasts and avoiding drastic decreases in their Ψs . This tolerance could have important implications for predicting the impact of climate change on natural desert regeneration, as well as for planning reforestation-afforestation practices, and rural land uses.

  20. Reply to “Introducing International Journal of Anatomical Variations”

    Directory of Open Access Journals (Sweden)

    Potu BK

    2009-07-01

    Full Text Available To the Editor, International Journal of Anatomical Variations:Please accept my heartiest congratulations on your recent opening of International Journal of Anatomical Variations Journal. I have already gone through the articles of first volume. It was surprised to read some of the unique variations published in it. Reading of these variations by vascular surgeons and angiologist will certainly boost their knowledge for better diagnosis and I hope you will continue publishing these types of rare variations. It would be great, if you encourage authors to submit research related articles. It is obvious that you have a wide-open future ahead of you.

  1. Anatomic Total Shoulder System

    Medline Plus

    Full Text Available ... advancing the standard of orthopedic patient care. In a few moments, you'll be able to watch a live global AP anatomic total shoulder surgery from Methodist Hospital in Philadelphia. A revolution in shoulder orthopedics, the Global AP gives ...

  2. Anatomical variation of piriformis muscle as a cause of deep gluteal pain: diagnosis using MR neurography and treatment Variação anatômica do músculo piriforme como causa de dor glútea profunda: diagnóstico por neurografia RM e seu tratamento

    OpenAIRE

    Giancarlo Cavalli Polesello; Marcelo Cavalheiro de Queiroz; João Paulo Tavares Linhares; Denise Tokechi Amaral; Nelson Keiske Ono

    2013-01-01

    Female patient, 42 years old with a history of low back pain on the left for seventeen years in which the definitive diagnosis of the etiology of pain was evident after the completion of neurography magnetic resonance imaging of the sciatic nerve. In this test it was identified the presence of an anatomical variation in the relationship between the piriformis muscle and sciatic nerve. We discuss details of this imaging technique and its importance in the frames of refractory low back pain. We...

  3. Significant Causes and Effects of Variation Orders in Construction Projects

    Directory of Open Access Journals (Sweden)

    Aftab Hameed Memon

    2014-05-01

    Full Text Available Variation Order (VO is a common phenomenon in construction projects. It involves an amendment of the original scope of work as in the contract. VO is caused from various factors. Variations often cause disputes and dissatisfactions among the parties involved in construction projects. Thus, it is very important to control VOs in a construction project. For this, the first step is to uncover and understand the causes and effects of VO. Hence, the aim of this study is to determine the significant causes and effects of VO in construction projects. Data collection involved the survey with a structured questionnaire consisting of 18 causes and 9 effects of variation orders identified through comprehensive literature review. Survey was carried out among client representatives, consultants and contractors involved in handling projects of Malaysian Public Works Department (PWD known as Jabatan Kerja Raya Malaysia (JKR. A total of 101 completed questionnaire sets were collected against 200 questionnaires distributed among the practitioners. Collected questionnaires were analyzed with statistical software package SPSS and Average Index formula. The results of the study showed that in Malaysia’s JKR projects often variation orders are occurred; these VO’s are majorly caused because of unavailability of equipment, poor workmanship and design complexity. While most significant effects of VO on the projects are increased project cost, delay in completion and logistic delays. Early participation of professionals may be beneficial in reducing the occurrence of variations. Also, improved design and avoiding frequent design changes will be very effective in controlling the problem of variations.

  4. Seismic reflectivity effects from seasonal seafloor temperature variation

    Science.gov (United States)

    Wood, Warren T.; Martin, Kylara M.; Jung, Wooyeol; Sample, John

    2014-10-01

    The effects of seasonal temperature variation on sound speed contrasts at the seafloor are usually considered negligible in the analysis of seismic data but may be significant at large incidence angles (offsets) important for inversion of sediment elastic properties, or long-range acoustic transmission. In coastal areas, the maximum annual seafloor temperature variation can be several degrees Celsius or more, corresponding to a sound speed variation of 30 m/s or more. Thermal pulses propagate via conduction several meters into the seafloor resulting in a damped quasi-sinusoidal temperature profile with predictable wave number characteristics. The oscillating seasonal and spatial character of this signal creates a time- and frequency-dependent effect on the elastic seafloor reflectivity. Results of numerical simulations show that the expected temperature profile for most sediment types and porosities will have the strongest affect on frequencies between about 60 and 600 Hz, at incidence angles greater than about 50°.

  5. Effect of anatomical noise on the detectability of cone beam CT images with different slice direction, slice thickness, and volume glandular fraction.

    Science.gov (United States)

    Han, Minah; Park, Subok; Baek, Jongduk

    2016-08-22

    We investigate the effect of anatomical noise on the detectability of cone beam CT (CBCT) images with different slice directions, slice thicknesses, and volume glandular fractions (VGFs). Anatomical noise is generated using a power law spectrum of breast anatomy, and spherical objects with diameters from 1mm to 11mm are used as breast masses. CBCT projection images are simulated and reconstructed using the FDK algorithm. A channelized Hotelling observer (CHO) with Laguerre-Gauss (LG) channels is used to evaluate detectability for the signal-known-exactly (SKE) binary detection task. Detectability is calculated for various slice thicknesses in the transverse and longitudinal planes for 15%, 30% and 60% VGFs. The optimal slice thicknesses that maximize the detectability of the objects are determined. The results show that the β value increases as the slice thickness increases, but that thicker slices yield higher detectability in the transverse and longitudinal planes, except for the case of a 1mm diameter spherical object. It is also shown that the longitudinal plane with a 0.1mm slice thickness provides higher detectability than the transverse plane, despite its higher β value. With optimal slice thicknesses, the longitudinal plane exhibits better detectability for all VGFs and spherical objects. PMID:27557168

  6. Anatomical study of aortic arch branches' variations with MRA and its significance%主动脉弓分支变异的MRA解剖学分析及其临床意义

    Institute of Scientific and Technical Information of China (English)

    李淑华; 狄玉进; 徐金法; 白敏; 陈军; 布春青

    2011-01-01

    目的:应用磁共振血管成像(MRA)分析主动脉弓分支变异的解剖学特征,探讨MRA评价主动脉弓分支变异的临床意义.方法:对1300例在我院磁共振室接受主动脉弓及其以上MRA检查的患者进行回顾性分析,分析不同类型主动脉弓分支变异的发生情况,并讨论主动脉弓分支变异的临床意义.结果:1300例患者中,形态正常者1207例(92.85%).即头臂干(BT)、左颈总动脉(LCCA)、左锁骨下动脉(LSA)从右向左分别发自主动脉弓,存在变异者93例(7.15%).共发现9种不同类型的变异.包括LCCA与BT共干发自主动脉弓43例(3.31%)·左椎动脉(LVA)于LCCA和LSA之间直接发自主动脉弓28例(2.15%).右颈总动脉(RCCA)直接发自主动脉弓伴迷走右锁骨下动脉(RSA)7例(0.54%).LCCA与RCCA共干发自主动脉弓伴迷走RSA 3例(0.23%).LCCA与BT共干,伴LVA直接发自主动脉弓5例(0.38%).LVA与LSA共干发自主动脉弓3例(0.23%).RCCA发自主动脉弓,右椎动脉(RVA)发自RCCA伴迷走RSA 2例(0.15%),LCCA,RCCA,LVA,RSA均发自主动脉弓1例(0.08%).LCCA与BT共干发自主动脉弓,LVA缺如,伴原始三叉动脉1例(0.08%).结论:主动脉弓分支变异种类繁多,MRA能很好的评价主动脉弓分支数量及其形态与开口位置,对临床有重要意义.%Objective : To evaluate the anatomical features of human aortic arch branch variations using magnetic resonance angiography (MRA) and its clinical significance, Methods;1300 patients who received aortic arch MRA were analyzed retrospectively. The aortic arch branch variations were summarized and the clinical significance was researched. Results : In 1300 cases.1207 of them ( 92. 85%) , which was a normal form, the brachiacephalic trunk ( BT) , left common carotid artery (LCCA) and left subclavian artery (LSA) originated separately from the aortic arch and 93 of them (7. 15%) were a variation form. Nine different types were found In 43 cases (3. 31%), BT and LCCA had a common trunk

  7. 翠柏木材解剖性质和结晶度的径向变异及化学性质%Wood Anatomical Properties of Calocedrus macrolepis and Radial Variation and Chemical Property of Crystallinity

    Institute of Scientific and Technical Information of China (English)

    崔凯; 孙庆丰; 廖声熙; 石江涛; 王小庆; 李昆

    2012-01-01

    对云南省昌宁产翠柏木材各生长轮间的解剖参数、结晶度的径向变异趋势和它们的相关性及化学性质做了全面的测定和分析.结果表明:管胞形态、胞壁率和结晶度总体径向变化趋势随生长轮龄的增加而增加,20~25a后趋于稳定;微纤丝角的径向变异趋势随着生长轮龄的增加而降低,20~25 a后趋于稳定;组织比量无明显变异规律.相关分析表明,结晶度与管胞长度、宽度和壁厚、胞壁率呈极显著正相关,相关系数分别为0.984、0.978、0.951和0.950;与微纤丝角间呈极显著负相关,相关系数为0.934;与组织比量无显著相关;据此建立了木材结晶度与各解剖参数的预测模型,相关系数均在0.9以上.化学性质分析表明翠柏木材纤维素的质量分数是42.63%,综纤维素的质量分数是68.31%,木质素的质量分数是20.72%;乙醚、苯醇、1% NaOH、热水、冷水的质量分数分别是3.41%、10.26%、21.55%、5.83%和3.52%;灰分的质量分数为0.42%;pH值为5.89.%An experiment was conducted to study the radial variation and correlations of wood anatomical parameters and crystal-linity in each growth ring of Calocedrus macrolepis Kurz. in Changning County, Yunan Province. The chemical properties of wood were determined. Results indicated that tracheid morphological features. cell wall ratio and crystallinity increased with increasing age of growth rings, and tended to be stable at 20-25 years; microfibrillar angle gradually decreased and also tended to be stable at 20?5 years; while tissue proportion showed an unobvious change. Correlation analysis of crystallinity and anatomical features indicated that the crystallinity was significantly positively correlated with tracheid length, width and wall thickness and cell wall ratio, and the correlation coefficients ( R2 ) were 0.984, 0.978 , 0.951 and 0.950, respectively. A significantly negative correlation was observed

  8. K Variations and Anisotropy: Microstructure Effect and Numerical Predictions

    Institute of Scientific and Technical Information of China (English)

    李旭东; 李华清

    2003-01-01

    Computer experiments were performed on simulated polycrystalline material samples that possess locally anisotropic microstructures to investigate stress intensity factor ( K ) variations and anisotropy along fronts of microcracks of different sizes. The anisotropic K , arising from inhomogeneous stresses in broken grains, was determined for planar microcracks by using a weight function-based numerical technique. It has been found that the grain-orientation-geometry-induced local anisotropy produces large variations in K along front of microcracks, when the crack size is of the order of few grain diameters. Synergetic effect of grain orientation and geometry of broken grains control K variations and evolution along the microcrack front. The K variations may diminish at large crack sizes, signifying a shift of K calculation to bulk stress dependence from local stress dependence. Local grain geometry and texture may lead to K anisotropy, producing unusually higher/lower K at a segment of the crack front. Either K variation or anisotropy cannot be ignored when assessing a microcrack.

  9. Reference Man anatomical model

    Energy Technology Data Exchange (ETDEWEB)

    Cristy, M.

    1994-10-01

    The 70-kg Standard Man or Reference Man has been used in physiological models since at least the 1920s to represent adult males. It came into use in radiation protection in the late 1940s and was developed extensively during the 1950s and used by the International Commission on Radiological Protection (ICRP) in its Publication 2 in 1959. The current Reference Man for Purposes of Radiation Protection is a monumental book published in 1975 by the ICRP as ICRP Publication 23. It has a wealth of information useful for radiation dosimetry, including anatomical and physiological data, gross and elemental composition of the body and organs and tissues of the body. The anatomical data includes specified reference values for an adult male and an adult female. Other reference values are primarily for the adult male. The anatomical data include much data on fetuses and children, although reference values are not established. There is an ICRP task group currently working on revising selected parts of the Reference Man document.

  10. 解剖构造对人工林樟子松单板染色效果的影响%Influence of Anatomical Characteristics on Dyeing Effects of Veneer from Pinus sylvestris var. Mongolica Plantations

    Institute of Scientific and Technical Information of China (English)

    管雪梅; 郭明辉

    2012-01-01

    An experiment was conducted to study the main anatomical factors influencing wood dyeing effects using Pinus syhestris var. mongolica plantations as study objects. Related indexes of wood anatomical structure and dyeing effects were determined, and a multiple regression analysis was made to analyze the correlations between wood anatomical structure and dyeing effects. Results show that there is a high correlation between dyeing effects and wood anatomical factors, and the multiple correlation coefficients between wood anatomical factors and various dyeing effect indexes range from 0.573 to 0.786. The main anatomical factors influencing wood dyeing effects of P. syhestris var. mongolica are tracheid proportion, wood ray proportion, resin canal proportion, and late wood tracheid length, etc.%以人工林樟子松为研究对象,通过测定樟子松单板解剖构造与染色效果的相关指标,对其进行多元回归分析,确定了影响木材染色效果的主要解剖因子.结果表明,解剖因子与其各染色效果指标间的复相关系数在0.573~0.786.影响樟子松木材染色效果的主要解剖因子为管胞比量、木射线比量、树脂道比量和晚材管胞长度等.

  11. A Multivariate Variational Principle for Piezoelectric Effect Problems

    Institute of Scientific and Technical Information of China (English)

    Ke Zunping; Chen Dapeng; Pian T. H. H

    1996-01-01

    The mechanical-electric coupling effect of piezoelectric materials and devices is discussed and a brief review on the evolution of the technique is presented. On such basis,as a first step toward the formulation of finite elements for analysis of piezoelectric devices, a multivariate variation principle is presented. As has been revealed by the present work,an important particularization thereof is the Allik-Hughes functional.

  12. Sex-specific genetic effects influence variation in body composition

    OpenAIRE

    Zillikens, Carola; Yazdanpanah, Mojgan; Pardo Cortes, Luba; Rivadeneira Ramirez, Fernando; Aulchenko, Yurii; Oostra, Ben; Uitterlinden, André; Pols, Huib; Tikka-Kleemola, Päivi

    2008-01-01

    textabstractAims/hypothesis: Despite well-known sex differences in body composition it is not known whether sex-specific genetic or environmental effects contribute to these differences. Methods: We assessed body composition in 2,506 individuals, from a young Dutch genetic isolate participating in the Erasmus Rucphen Family study, by dual-energy X-ray absorptiometry and anthropometry. We used variance decomposition procedures to partition variation of body composition into genetic and environ...

  13. Variation of force amplitude and its effects on local fatigue.

    Science.gov (United States)

    Yung, Marcus; Mathiassen, Svend Erik; Wells, Richard P

    2012-11-01

    Trends in industry are leaning toward stereotyped jobs with low workloads. Physical variation is an intervention to reduce fatigue and potentially musculoskeletal disorders in such jobs. Controlled laboratory studies have provided some insight into the effectiveness of physical variation, but very few have been devoted to force variation without muscular rest as a component. This study was undertaken to determine multiple physiological responses to five isometric elbow extension protocols with the same mean amplitude (15% maximum voluntary contraction, MVC), cycle time (6 s), and duty cycle (50 %). Sustained (15 %Sus) and intermittent contractions including zero force (0-30 %Int) differed significantly in 19 of 27 response variables. Contractions varying by half the mean force (7.5-22.5 %Int) led to 8 and 7 measured responses that were significantly different from 0-30 %Int and 15 %Sus, respectively. A sinusoidal condition (0-30 %Sine) resulted in 2 variables that were significantly different from 0-30 %Int, and 16 different from 15 %Sus. Finally, ten response variables suggested that varying forces with 1 % as the lower contraction level was significantly less fatiguing than 15 %Sus, while no responses were significantly different from 0-30 %Int. Sustained contractions led to decreased twitch force 24-h post-exercise, whereas recovery was complete within 60 min after intermittent contractions. This suggests that time-varying force may be a useful intervention to reduce local fatigue in workers performing low-load tasks, and also that rest per se did not seem to cause any extraordinary effects beyond those predictable from the force variation amplitude. PMID:22407330

  14. Diffeomorphic Anatomical Registration Through Exponentiated Lie Algebra provides reduced effect of scanner for cortex volumetry with atlas-based method in healthy subjects

    Energy Technology Data Exchange (ETDEWEB)

    Goto, Masami; Ino, Kenji; Yano, Keiichi [University of Tokyo Hospital, Department of Radiological Technology, Bunkyo-ku, Tokyo (Japan); Abe, Osamu [Nihon University School of Medicine, Department of Radiology, Itabashi-ku, Tokyo (Japan); Aoki, Shigeki [Juntendo University, Department of Radiology, Bunkyo-ku, Tokyo (Japan); Hayashi, Naoto [University of Tokyo Hospital, Department of Computational Diagnostic Radiology and Preventive Medicine, Bunkyo-ku, Tokyo (Japan); Miyati, Tosiaki [Kanazawa University, Graduate School of Medical Science, Kanazawa (Japan); Takao, Hidemasa; Mori, Harushi; Kunimatsu, Akira; Ohtomo, Kuni [University of Tokyo Hospital, Department of Radiology and Department of Computational Diagnostic Radiology and Preventive Medicine, Bunkyo-ku, Tokyo (Japan); Iwatsubo, Takeshi [University of Tokyo, Department of Neuropathology, Bunkyo-ku, Tokyo (Japan); Yamashita, Fumio [Iwate Medical University, Department of Radiology, Yahaba, Iwate (Japan); Matsuda, Hiroshi [Integrative Brain Imaging Center National Center of Neurology and Psychiatry, Department of Nuclear Medicine, Kodaira, Tokyo (Japan); Collaboration: Japanese Alzheimer' s Disease Neuroimaging Initiative

    2013-07-15

    This study aimed to investigate whether the effect of scanner for cortex volumetry with atlas-based method is reduced using Diffeomorphic Anatomical Registration Through Exponentiated Lie Algebra (DARTEL) normalization compared with standard normalization. Three-dimensional T1-weighted magnetic resonance images (3D-T1WIs) of 21 healthy subjects were obtained and evaluated for effect of scanner in cortex volumetry. 3D-T1WIs of the 21 subjects were obtained with five MRI systems. Imaging of each subject was performed on each of five different MRI scanners. We used the Voxel-Based Morphometry 8 tool implemented in Statistical Parametric Mapping 8 and WFU PickAtlas software (Talairach brain atlas theory). The following software default settings were used as bilateral region-of-interest labels: ''Frontal Lobe,'' ''Hippocampus,'' ''Occipital Lobe,'' ''Orbital Gyrus,'' ''Parietal Lobe,'' ''Putamen,'' and ''Temporal Lobe.'' Effect of scanner for cortex volumetry using the atlas-based method was reduced with DARTEL normalization compared with standard normalization in Frontal Lobe, Occipital Lobe, Orbital Gyrus, Putamen, and Temporal Lobe; was the same in Hippocampus and Parietal Lobe; and showed no increase with DARTEL normalization for any region of interest (ROI). DARTEL normalization reduces the effect of scanner, which is a major problem in multicenter studies. (orig.)

  15. Antidepressant-like behavioral, anatomical, and biochemical effects of petroleum ether extract from maca (Lepidium meyenii) in mice exposed to chronic unpredictable mild stress.

    Science.gov (United States)

    Ai, Zhong; Cheng, Ai-Fang; Yu, Yuan-Tao; Yu, Long-Jiang; Jin, Wenwen

    2014-05-01

    Maca has been consumed as a medical food in Peru for thousands of years, and exerts anxiolytic and antidepressant effects. Our present study aimed to evaluate the behavior and anatomical and biochemical effects of petroleum ether extract from maca (ME) in the chronic unpredictable mild stress (CUMS) model of depression in mice. Three different doses of maca extract (125, 250, and 500 mg/kg) were orally administrated in the six-week CUMS procedure. Fluoxetine (10 mg/kg) was used as a positive control drug. Maca extract (250 and 500 mg/kg) significantly decreased the duration of immobility time in the tail suspension test. After treatment with maca extract (250 and 500 mg/kg), the granule cell layer in the dentate gyrus appeared thicker. Maca extract (250 and 500 mg/kg) also induced a significant reduction in corticosterone levels in mouse serum. In mouse brain tissue, after six weeks of treatment, noradrenaline and dopamine levels were increased by maca extract, and the activity of reactive oxygen species was significantly inhibited. Serotonin levels were not significantly altered. These results demonstrated that maca extract (250 and 500 mg/kg) showed antidepressant-like effects and was related to the activation of both noradrenergic and dopaminergic systems, as well as attenuation of oxidative stress in mouse brain. PMID:24730393

  16. Effects of UV-B radiation on anatomical characteristics, phenolic compounds and gene expression of the phenylpropanoid pathway in highbush blueberry leaves.

    Science.gov (United States)

    Inostroza-Blancheteau, Claudio; Reyes-Díaz, Marjorie; Arellano, Alejandro; Latsague, Mirtha; Acevedo, Patricio; Loyola, Rodrigo; Arce-Johnson, Patricio; Alberdi, Miren

    2014-12-01

    The effects of increased doses of UV-B radiation on anatomical, biochemical and molecular features of leaves of two highbush blueberry (Vaccinium corymbosum L. cv. Brigitta and Bluegold) genotypes were investigated. Plants were grown in a solid substrate and exposed to 0, 0.07, 0.12 and 0.19 Wm(-2) of biologically effective UV-B radiation for up to 72 h. Leaf thickness and the adaxial epidermis thickness fell more than 3-fold in both genotypes at the highest UV-B dose. Moreover, in Bluegold an evident disorganization in the different cell layers was observed at the highest UV-B radiation. A significant decrease in chlorophyll a/b after 6 h in Brigitta under the greater UV-B doses was observed. Anthocyanin and total phenolics were increased, especially at 0.19 Wm(-2), when compared to the control in both genotypes.Chlorogenic acid was the most abundant hydroxycinnamic acid in Brigitta, and was significantly higher (P ≤ 0.05) than in Bluegold leaves. Regarding the expression of phenylpropanoid genes, only the transcription factor VcMYBPA1 showed a significant and sustained induction at higher doses of UV-B radiation in both genotypes compared to the controls. Thus, the reduction of leaf thickness concomitant with a lower lipid peroxidation and rapid enhancement of secondary metabolites, accompanied by a stable induction of the VcMYBPA1 transcription factor suggest a better performance against UV-B radiation of the Brigitta genotype.

  17. Entropy variation in isothermal fluid flow considering real gas effects

    Directory of Open Access Journals (Sweden)

    Maurício Guimarães da Silva

    2011-01-01

    Full Text Available The present paper concerns on the estimative of the pressure loss and entropy variation in an isothermal fluid flow, considering real gas effects. The 1D formulation is based on the isothermal compressibility module and on the thermal expansion coefficient in order to be applicable for both gas and liquid as pure substances. It is emphasized on the simple methodology description, which establishes a relationship between the formulation adopted for ideal gas and another considering real gas effects. A computational procedure has been developed, which can be used to determine the flow properties in duct with a variable area, where real gas behavior is significant. In order to obtain quantitative results, three virial coefficients for Helium equation of state are employed to determine the percentage difference in pressure and entropy obtained from different formulations. Results are presented graphically in the form of real gas correction factors, which can be applied to perfect gas calculations.

  18. Automatic exposure control in CT: the effect of patient size, anatomical region and prescribed modulation strength on tube current and image quality

    Energy Technology Data Exchange (ETDEWEB)

    Papadakis, Antonios E. [University Hospital of Heraklion, Department of Medical Physics, Stavrakia, P.O. Box 1352, Heraklion, Crete (Greece); Perisinakis, Kostas; Damilakis, John [University of Crete, Faculty of Medicine, Department of Medical Physics, P.O. Box 2208, Heraklion, Crete (Greece)

    2014-10-15

    To study the effect of patient size, body region and modulation strength on tube current and image quality on CT examinations that use automatic tube current modulation (ATCM). Ten physical anthropomorphic phantoms that simulate an individual as neonate, 1-, 5-, 10-year-old and adult at various body habitus were employed. CT acquisition of head, neck, thorax and abdomen/pelvis was performed with ATCM activated at weak, average and strong modulation strength. The mean modulated mAs (mAs{sub mod}) values were recorded. Image noise was measured at selected anatomical sites. The mAs{sub mod} recorded for neonate compared to 10-year-old increased by 30 %, 14 %, 6 % and 53 % for head, neck, thorax and abdomen/pelvis, respectively, (P < 0.05). The mAs{sub mod} was lower than the preselected mAs with the exception of the 10-year-old phantom. In paediatric and adult phantoms, the mAs{sub mod} ranged from 44 and 53 for weak to 117 and 93 for strong modulation strength, respectively. At the same exposure parameters image noise increased with body size (P < 0.05). The ATCM system studied here may affect dose differently for different patient habitus. Dose may decrease for overweight adults but increase for children older than 5 years old. Care should be taken when implementing ATCM protocols to ensure that image quality is maintained. circle ATCM efficiency is related to the size of the patient's body. (orig.)

  19. Numerical simulation of pharyngeal airflow applied to obstructive sleep apnea: effect of the nasal cavity in anatomically accurate airway models.

    Science.gov (United States)

    Cisonni, Julien; Lucey, Anthony D; King, Andrew J C; Islam, Syed Mohammed Shamsul; Lewis, Richard; Goonewardene, Mithran S

    2015-11-01

    Repetitive brief episodes of soft-tissue collapse within the upper airway during sleep characterize obstructive sleep apnea (OSA), an extremely common and disabling disorder. Failure to maintain the patency of the upper airway is caused by the combination of sleep-related loss of compensatory dilator muscle activity and aerodynamic forces promoting closure. The prediction of soft-tissue movement in patient-specific airway 3D mechanical models is emerging as a useful contribution to clinical understanding and decision making. Such modeling requires reliable estimations of the pharyngeal wall pressure forces. While nasal obstruction has been recognized as a risk factor for OSA, the need to include the nasal cavity in upper-airway models for OSA studies requires consideration, as it is most often omitted because of its complex shape. A quantitative analysis of the flow conditions generated by the nasal cavity and the sinuses during inspiration upstream of the pharynx is presented. Results show that adequate velocity boundary conditions and simple artificial extensions of the flow domain can reproduce the essential effects of the nasal cavity on the pharyngeal flow field. Therefore, the overall complexity and computational cost of accurate flow predictions can be reduced.

  20. Solar UV radiation variations and their stratospheric and climatic effects

    Science.gov (United States)

    Donnelly, R. F.; Heath, D. F.

    1985-01-01

    Nimbus-7 SBUV measurements of the short-term solar UV variations caused by solar rotation and active-region evolution have determined the amplitude and wavelength dependence for the active-region component of solar UV variations. Intermediate-term variations lasting several months are associated with rounds of major new active regions. The UV flux stays near the peak value during the current solar cycle variation for more than two years and peaks about two years later than the sunspot number. Nimbus-7 measurements have observed the concurrent stratospheric ozone variations caused by solar UV variations. There is now no doubt that solar UV variations are an important cause of short- and long-term stratospheric variations, but the strength of the coupling to the troposphere and to climate has not yet been proven.

  1. Effects of viscosity variations in temporal mixing layer

    International Nuclear Information System (INIS)

    The objective of the present investigation is to assess the effects of viscosity variations in low-speed temporally-evolving turbulent mixing layer. Direct Numerical Simulations (DNS) are performed for several viscosity ratios, Rv = vhigh/vlow, varying between 1 and 9, whereas the upper and lower streams are of equal density. The space-time evolution of Variable-Viscosity Flow (VVF) is compared with the Constant-Viscosity Flow (CVF), for which Rv = 1. The initial Reynolds number, based on the initial momentum thickness, δθ,0, is Reδθ,0 = 160 for the considered cases. The study focuses on the first stages of the temporal evolution of the mixing-layer. It is shown that in VVF (with respect to CVF): (i) the birth of turbulent fluctuations is accelerated; (ii) large-scale quantities, i.e. mean longitudinal velocity and momentum thickness, are affected by the viscosity variations, thus dispelling the myth that viscosity is a 'small-scale quantity that does not affect the large scales'; (iii) the velocity fluctuations are enhanced for VVF. In particular, the turbulent kinetic energy peaks earlier and is three times larger for VVF than CVF at the earliest stage of the mixing, and (iv) the transport equation for the turbulent kinetic energy is derived and favourably compared with simulations data.

  2. Bilateral lingual-facial trunk: anatomic and clinical implications.

    Science.gov (United States)

    Troupis, T; Michalinos, A; Kakisis, J; Natsis, K; Sofidis, G; Skandalakis, P

    2015-01-01

    Common origin of lingual and facial artery is a relatively frequent anatomic varia-tion. Instead, bilateral lingual-facial trunk has been described only sparsely in the literature. In this report authors describe and analyse a case of bilateral common lingual-facial trunk in the context of its anatomical, clinical and embryological implications. We also describe possible consequences in performance of elective and emergent surgical operations and modification in surgical techniques that should be considered. We believe that surgeons should be suspicious for this variation's existence and keep alternative solutions in their armentarium.

  3. Detection of 160 min solar intensity variations: Sampling effect

    International Nuclear Information System (INIS)

    The hypothesis that the 2h40m period in the Crimean and Stanford global solar velocity oscillation measurements, which is close to a 1/9 of a day, might be produced partly by a 1-day sampling regularity in observations, is checked using the IR center-limb intensity variations measurements. We find: a) The power spectrum of the series of these data does show a peak near the 2 h 40 m period. b) Power spectra of the series with observing windows 'filled' with a constant do not exhibit a significant peak at the 9th harmonic of a day, nor do the power spectra of the set with observing windows 'filled' with randomly generated numbers. Accordingly, we conclude that the analysis performed on the really observed data is not biased by the effect of data windows and a 1-day sampling regularity of observations. (orig.)

  4. The effect of anatomical modeling on space radiation dose estimates: a comparison of doses for NASA phantoms and the 5th, 50th, and 95th percentile male and female astronauts

    Energy Technology Data Exchange (ETDEWEB)

    Bahadori, Amir A; Bolch, Wesley E [Department of Nuclear and Radiological Engineering, University of Florida, Gainesville, FL 32611 (United States); Van Baalen, Mary; Semones, Edward J [NASA Johnson Space Center, Houston, TX 77058 (United States); Shavers, Mark R [Wyle Integrated Science and Engineering, Houston, TX 77058 (United States); Dodge, Charles, E-mail: wbolch@ufl.edu [University of Houston-Downtown, Houston, TX 77002 (United States)

    2011-03-21

    The National Aeronautics and Space Administration (NASA) performs organ dosimetry and risk assessment for astronauts using model-normalized measurements of the radiation fields encountered in space. To determine the radiation fields in an organ or tissue of interest, particle transport calculations are performed using self-shielding distributions generated with the computer program CAMERA to represent the human body. CAMERA mathematically traces linear rays (or path lengths) through the computerized anatomical man (CAM) phantom, a computational stylized model developed in the early 1970s with organ and body profiles modeled using solid shapes and scaled to represent the body morphometry of the 1950 50th percentile (PCTL) Air Force male. With the increasing use of voxel phantoms in medical and health physics, a conversion from a mathematical-based to a voxel-based ray-tracing algorithm is warranted. In this study, the voxel-based ray tracer (VoBRaT) is introduced to ray trace voxel phantoms using a modified version of the algorithm first proposed by Siddon (1985 Med. Phys. 12 252-5). After validation, VoBRAT is used to evaluate variations in body self-shielding distributions for NASA phantoms and six University of Florida (UF) hybrid phantoms, scaled to represent the 5th, 50th, and 95th PCTL male and female astronaut body morphometries, which have changed considerably since the inception of CAM. These body self-shielding distributions are used to generate organ dose equivalents and effective doses for five commonly evaluated space radiation environments. It is found that dosimetric differences among the phantoms are greatest for soft radiation spectra and light vehicular shielding.

  5. EFFECTS OF FOCUS FILM DISTANCE (FFD) VARIATION ON ENTRANCE TESTICULAR DOSE IN LUMBAR-PELVIC RADIOGRAPHY

    OpenAIRE

    Dilger, Ron; Egan, Ingrid; Hayek, Ray

    1997-01-01

    Introduction: With the steady increase in public and professional concern regarding the biological effects of ionising radiation, there is a need for both the Chiropractic and Radiography professions to improve imaging techniques for the lowering of patient radiation doses. Lumbar radiographs are essential in chiropractic general practice for biomechanical diagnosis and postural analysis. Detailed anatomical measurements are taken from spinal radiographs for the determination of various biome...

  6. ANATOMICAL PROPERTIES OF PLANTAGO ARENARIA

    OpenAIRE

    Nicoleta IANOVICI; SINITEAN, Adrian; Aurel FAUR

    2011-01-01

    Psammophytes are marked by a number of adaptations that enable them to exist in the hard environmental conditions of the sand habitats. In this study, the anatomical characteristics of Plantago arenaria were examined. Studies were conducted to assess the diversity of anatomical adaptations of vegetative organs in this taxa. Results are presented with original photographs. The analysis of leaf anatomy in P. arenaria showed that the leaves contained a contained xeromorphic traits. Arbuscular my...

  7. Quantitation of maxillary remodeling. 2. Masking of remodeling effects when an "anatomical" method of superimposition is used in the absence of metallic implants.

    Science.gov (United States)

    Baumrind, S; Korn, E L; Ben-Bassat, Y; West, E E

    1987-06-01

    We report the results of a study aimed at quantifying the differences in the perceived pattern of maxillary remodeling that are observed when different methods are used to superimpose maxillary images in roentgenographic cephalometrics. In a previous article, we reported cumulative changes in the positions of anterior nasal spine (ANS), posterior nasal spine (PNS), and Point A for a sample of 31 subjects with maxillary metallic implants. Measurements had been made on lateral cephalograms taken at annual intervals relative to superimposition on the implants. In the present article, we quantify the differences in the perceived displacement of the same landmarks in the same sample when a standard "anatomical best bit" rule was used in lieu of superimposition on the implants. The anatomical best fit superimposition as herein defined was found in this sample to lose important information on the downward remodeling of the superior surface of the maxilla that had been detected when the implant superimposition was used. In fact, we observed a small artifactual upward displacement of the ANS-PNS line. In the anteroposterior direction, the tendency toward backward displacement of skeletal landmarks through time that had been detected with the implant superimposition was replaced by a small forward displacement of ANS and Point A together with reduced backward displacement of PNS. To the extent that the implant superimposition is to be considered the true and correct one, the anatomical best fit superimposition appears to understate the true downward remodeling of the palate by an average of about 0.3 and 0.4 mm per year, although this value differs at different ages and timepoints. The anatomical best fit superimposition also misses entirely the small mean tendency toward backward remodeling that was observed when the implant superimposition was used. In situations in which there are no implants, clinicians and research workers must necessarily continue to use anatomically

  8. Characterization and Management of Interfractional Anatomic Changes for Pancreatic Cancer Radiotherapy

    International Nuclear Information System (INIS)

    Purpose: To quantitatively characterize interfractional anatomic variations in pancreatic cancer radiotherapy (RT) and to study dosimetric advantages for using an online adaptive replanning scheme to account for these variations. Methods and Materials: Targets and organs at risk (OAR) were delineated by autosegmentation based on daily computed tomography (CT) images acquired using a respiration-gated in-room CT during daily image-guided RT (IGRT) for 10 pancreatic cancer patients. Various parameters, including the maximum overlap ratio (MOR) between the volumes based on planning and daily CTs for a structure, while the overlapping volumes were maximized, were used to quantify the interfractional organ deformation with the intrafractional variations largely excluded. An online adaptive RT (ART) was applied to these daily CTs. To evaluate the dosimetric benefits of ART, the dose distributions from the online ART were compared to those from the repositioning in the current standard IGRT practice. Results: The interfractional anatomic variations, particularly the organ deformation, are significant during pancreas irradiation. For the patients studied, the average MORs of all daily CTs were 80.2%, 61.7%, and 72.2% for pancreatic head, duodenum, and stomach, respectively. The online ART leads to improved dosimetric plan with better target coverage and/or OAR sparing than IGRT repositioning. For the patients studied, the mean V50.4Gy (volume covered by 50.4 Gy) for the duodenum was reduced from 43.4% for IGRT to 15.6% for the online ART scheme. Conclusions: The online adaptive RT scheme can effectively account for the significant interfractional anatomic variations observed in pancreas irradiation. The dosimetric advantages with the online ART may enable safe dose escalation in radiation therapy for pancreatic cancer.

  9. Effect of Anatomical Modeling on Space Radiation Dose Estimates: A Comparison of Doses for NASA Phantoms and 5th, 50th, and 95th Percentile UF Hybrid Phantoms

    Science.gov (United States)

    Bahadori, A.; VanBaalen, M.; Shavers, M.; Semones, E.; Dodge, C.; Bolch, W.

    2010-01-01

    The estimate of absorbed dose to individual organs of a space crewmember is affected by the geometry of the anatomical model of the astronaut used in the radiation transport calculation. For astronaut dosimetry, NASA currently uses the computerized anatomical male (CAM) and computerized anatomical female (CAF) stylized phantoms to represent astronauts in its operational radiation dose analyses. These phantoms are available in one size and in two body positions. In contrast, the UF Hybrid Adult Male and Female (UFHADM and UFHADF) phantoms have organ shapes based on actual CT data. The surfaces of these phantoms are defined by non-uniform rational B-spline surfaces, and are thus flexible in terms of body morphometry and extremity positioning. In this study, UFHADM and UFHADF are scaled to dimensions corresponding to 5th, 50th, and 95th percentile (PCTL) male and female astronauts. A ray-tracing program is written in Visual Basic 2008, which is then used to create areal density maps for dose points corresponding to various organs within the phantoms. The areal density maps, along with appropriate space radiation spectra, are input into the NASA program couplet HZETRN/BRYNTRN, and organ doses are calculated. The areal density maps selected tissues and organs of the 5th, 50th, and 95th PCTL male and female phantoms are presented and compared. In addition, the organ doses for the 5th, 50th, and 95th PCTL male and female phantoms are presented and compared to organ doses for CAM and CAF.

  10. ANATOMICAL LANDMARKS FOR ROBOTIC NERVE SPARING RADICAL PROSTATECTOMY

    Directory of Open Access Journals (Sweden)

    T. N. Moiseenko

    2013-01-01

    Full Text Available A detailed anatomical study of the prostate and pelvic organs has been recently relevant. Their anatomical knowledge is directly associated with the improved procedure of nerve-sparing robot-assisted radical prostatectomy, which contributes to the preservation of the anatomical structures responsible for postsurgical erection and urinary continence. The main tasks of radical prostatectomy are effective cancer control, early recovery of urinary continence, and recovery of erectile function.The literature on the anatomy of the prostate and its adjacent structures is analyzed in the context of nerve-sparing robot-assisted radical prostatectomy.

  11. Anatomic changes due to interspecific grafting in cassava (Manihot esculenta).

    Science.gov (United States)

    Bomfim, N; Ribeiro, D G; Nassar, N M A

    2011-05-31

    Cassava rootstocks of varieties UnB 201 and UnB 122 grafted with scions of Manihot fortalezensis were prepared for anatomic study. The roots were cut, stained with safranin and alcian blue, and examined microscopically, comparing them with sections taken from ungrafted roots. There was a significant decrease in number of pericyclic fibers, vascular vessels and tyloses in rootstocks. They exhibited significant larger vessels. These changes in anatomic structure are a consequence of genetic effects caused by transference of genetic material from scion to rootstock. The same ungrafted species was compared. This is the first report on anatomic changes due to grafting in cassava.

  12. ANATOMICAL PROPERTIES OF PLANTAGO ARENARIA

    Directory of Open Access Journals (Sweden)

    Nicoleta IANOVICI

    2011-01-01

    Full Text Available Psammophytes are marked by a number of adaptations that enable them to exist in the hard environmental conditions of the sand habitats. In this study, the anatomical characteristics of Plantago arenaria were examined. Studies were conducted to assess the diversity of anatomical adaptations of vegetative organs in this taxa. Results are presented with original photographs. The analysis of leaf anatomy in P. arenaria showed that the leaves contained a contained xeromorphic traits. Arbuscular mycorrhizal symbiosis seems to be critical for their survival.

  13. Population of anatomically variable 4D XCAT adult phantoms for imaging research and optimization

    Energy Technology Data Exchange (ETDEWEB)

    Segars, W. P.; Bond, Jason; Frush, Jack; Hon, Sylvia; Eckersley, Chris; Samei, E. [Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Williams, Cameron H.; Frush, D. [Department of Radiology, Duke University Medical Center, Durham, North Carolina 27710 (United States); Feng Jianqiao; Tward, Daniel J.; Ratnanather, J. T.; Miller, M. I. [Center for Imaging Science, Johns Hopkins University, Baltimore, Maryland 21218 (United States)

    2013-04-15

    as a jumping point from which to create an unlimited number of 3D and 4D variations for imaging research. Conclusions: A population of phantoms that includes a range of anatomical variations representative of the public at large is needed to more closely mimic a clinical study or trial. The series of anatomically variable phantoms developed in this work provide a valuable resource for investigating 3D and 4D imaging devices and the effects of anatomy and motion in imaging. Combined with Monte Carlo simulation programs, the phantoms also provide a valuable tool to investigate patient-specific dose and image quality, and optimization for adults undergoing imaging procedures.

  14. Naming the Soft Tissue Layers of the Temporoparietal Region: Unifying Anatomic Terminology Across Surgical Disciplines

    NARCIS (Netherlands)

    K.M. Davidge; W.R. van Furth; A. Agur; M. Cusimano

    2010-01-01

    BACKGROUND: The complexity of temporoparietal anatomy is compounded by inconsistent nomenclature. OBJECTIVE: To provide a comprehensive review of the variations in terminology and anatomic descriptions of the temporoparietal soft tissue layers, with the aim of improving learning and communication ac

  15. Portfolio Diversification Effects and Regular Variation in Financial Data

    NARCIS (Netherlands)

    N. Hyung (Namwon); C.G. de Vries (Casper)

    2001-01-01

    textabstractPortfolio risk is in an important way driven by 'abnormal' returns emanating from heavy tailed distributed asset returns. The theory of regular variation and extreme values provides a model for this feature of financial data. We first review this theory and subsequently study the problem

  16. Anatomical variation of obturator vessels and its practical risk: a case report from an anatomic study Variação anatômica de vasos obturatórios e seu risco prático: relato de caso de um estudo anatômico

    Directory of Open Access Journals (Sweden)

    Somayaji Nagabhooshana

    2008-09-01

    Full Text Available Obturator artery is frequently a branch of anterior division of the internal iliac artery. It has drawn attention of pelvic surgeons, anatomists and radiologists because of the high frequency of variations in its course and origin. The obturator vein is usually described as a tributary of the internal iliac vein. During routine dissection classes to undergraduate medical students we have observed obturator artery arising from external iliac artery, obturator vein draining into external iliac vein, communicating vein between obturator vein and external iliac vein and inferior epigastric artery arising from the obturator artery. The anomalous obturator vessels and inferior epigastric artery in the present case may be in a dangerous situation in pelvic surgeries that require dissection or suturing along the pelvic rim. Developmental reasons and clinical significances of the variations are discussed.A artéria obturatória é muitas vezes um ramo da divisão anterior da artéria ilíaca interna. Ela tem chamado atenção de cirurgiões pélvicos, anatomistas e radiologistas devido à alta freqüência de variações em seu trajeto e origem. A veia obturatória é geralmente descrita como uma tributária de veia ilíaca interna. Durante aulas de dissecação para estudantes de medicina, observamos a artéria obturatória surgindo a partir da artéria ilíaca externa, veia obturatória drenando para a veia ilíaca externa, veia comunicante entre a veia obturatória e a veia ilíaca externa e artéria epigástrica inferior surgindo a partir da artéria obturatória. Os vasos obturatórios anômalos e a artéria epigástrica inferior no presente caso podem se encontrar em situação perigosa em cirurgias pélvicas que exigem dissecação ou suturas ao longo da borda pélvica. Discutem-se as causas de desenvolvimento e a significância clínica das variações.

  17. Within-Individual Variation in Preferences Equity Effects of Congestion Charges

    DEFF Research Database (Denmark)

    Borjesson, Maria; Cherchi, Elisabetta; Bierlaire, Michel

    2013-01-01

    collected in Switzerland, a revealed stated preference logit mode choice model was estimated. The model was applied to simulate how VTT and change in consumer surplus vary across trips within and between individuals over the 6 weeks in response to a hypothetical congestion-charging scheme. The variation...... that variation in VTT between observed trips reflects the variation in the average VTT between individuals, which is usually made in equity analyses, will over-state the between-individual variation. The results suggest that if intraindividual variation in preferences is not taken into account, the negative...... equity effects of congestion charges are likely to be overestimated....

  18. The Effect of Hydroxyapatite Coating on Long-term Results of Total Hip Arthroplasty with Hydroxyapatite-coated Anatomic Femoral Stem

    Science.gov (United States)

    Im, Chae-Hyun; Kim, Dae-Hee; Heo, Ju-Yeong; Jang, Young-Jae

    2014-01-01

    Purpose To evaluate the clinical and radiological results, as well as the survival rate, associated with total hip arthroplasty using a hydroxyapatite (HA)-coated anatomical femoral stem at a follow-up of ≥12 years. Materials and Methods From April 1992 to May 1997, 86 patients (102 hips) underwent total hip arthroplasty with a HA-coated ABG I (Anatomical Benoist Giraud; Howmedica) hip prosthesis. The average age at the time of surgery was 53.4 years and the mean duration of follow-up was 17.1 years (range, 12.1-21.0 years). The Harris hip score (HHS) and radiographic assessments of thigh pain were used to evaluate the clinical results. We observed osteointegration, cortical hypertrophy, reactive line, calcar resorption and osteolysis around the femoral stems. The survival rate of the femoral stems was evaluated by using the span of time to a revision operation for any reasons was defined as the end point. Results The mean HHS was 50.5 preoperatively and 84.2 at the time of last follow-up. Osteolysis only around the HA-coated proximal portion of the femoral stem was observed in 72 hips, cortical hypertrophy all around the distal portion of the femoral stem was observed in 38 hips, and calcar resorption was observed in 44 hips. A reactive line was observed in 13 hips, but was unrelated to component loosening. Stem revision operations were performed in 24 (23%) hips due to osteolysis (14 hips), fracture (5 hips) and infection (5 hips). The femoral stem survival rate was 75% over the mean duration of follow-up. Conclusion Total hip arthroplasty using a HA-coated anatomical femoral stem showed necessitated a high rate of revision operations due to osteolysis around the femoral stem in this long term follow-up study.

  19. Effects of seasonal variations on thermoregulation of ostrich

    International Nuclear Information System (INIS)

    Twelve ostrich aged 7 months old were used during summer and winter from the breeding flock of the ostrich farm, at the Nuclear Research Center in Inshas, of Atomic Energy Authority, Egypt. In the study all birds were exposed to ambient temperatures in summer and winter, and the birds were fed grower ration ad libitum (19% protein and 2450 K cal ME /Kg).The present study was carried out to evaluate the effect of temperature variation during summer and winter seasons and diurnal effect on changes in some physiological and blood chemical parameters, the daily feed consumption (g/bird/day) and water consumption (ml/bird/day) these parameters were measured during 7 days in each season. Cloacal temperatures was measured and blood samples were taken twice, one in the morning at 7 am and once in the afternoon at 3 pm during a representative 7 hot days of June (40±2 degree C) (summer) and the 7 cold days of January (18±2 degree C) (winter). Red blood cell (RBCs) counts and total white blood cell (WBCs) counts, hemoglobin concentration (Hb) and packed cell volume (PCV) were determined. Mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular hemoglobin concentrations (MCHC) were calculated. Serum, total protein (TP), albumen (A) and globulin (G) concentrations were measured. Furthermore, serum alanine transaminase (ALT), aspartate transaminase (AST), glucose and triglycerides concentrations were determined. Also, serum triiodothyronine (T3), and aldosterone levels were estimated. Also, the amount of total body water was determined by the antipyren method. Finally, serum protein profile it was conducted by Native-PAGE method (Native polyacrylamide gel electrophoresis) on vertical slab gel to determine protein profiles in blood proteins of ostrich. Results indicated that feed consumption unlike water consumption was significantly increased during winter than in summer season. Moreover, body temperature increased significantly during the summer

  20. Effects of Extreme Obliquity Variations on the Habitability of Exoplanets

    CERN Document Server

    Armstrong, J C; Domagal-Goldman, S; Breiner, J; Quinn, T R; Meadows, V S

    2014-01-01

    We explore the impact of obliquity variations on planetary habitability in hypothetical systems with high mutual inclination. We show that large amplitude, high frequency obliquity oscillations on Earth-like exoplanets can suppress the ice-albedo feedback, increasing the outer edge of the habitable zone. We restrict our exploration to hypothetical systems consisting of a solar-mass star, an Earth-mass planet at 1 AU, and 1 or 2 larger planets. We verify that these systems are stable for $10^8$ years with N-body simulations, and calculate the obliquity variations induced by the orbital evolution of the Earth-mass planet and a torque from the host star. We run a simplified energy balance model on the terrestrial planet to assess surface temperature and ice coverage on the planet's surface, and we calculate differences in the outer edge of the habitable zone for planets with rapid obliquity variations. For each hypothetical system, we calculate the outer edge of habitability for two conditions: 1) the full evolu...

  1. Effect of technique variation on sensory nerve conduction characteristics.

    Science.gov (United States)

    Stone, L A

    1984-04-01

    The impact of technique variation on the wave-form characteristics of the evoked sensory potential was determined from the median and ulnar nerves of healthy subjects. The conduction characteristics of latency, amplitude, and duration were determined for orthodromic and antidromic techniques of stimulation as measured under each of three recording modes: 1) single evoked response, 2) superimposition, and 3) electronic averaging. Variation in the technique of stimulation significantly affected each of the three wave-form characteristics. Peak latency and duration of the evoked sensory potential were longer in antidromic stimulation. The amplitude of the sensory potential varied significantly with both recording and stimulating techniques. The amplitude of the sensory response was larger in antidromic stimulation than in orthodromic stimulation and also was found to be smaller with electronic averaging than with the other recording modes in both antidromic and orthodromic conduction techniques. This degree of variation requires that standardized techniques of methodology be established with the development of normal values for the particular laboratory.

  2. Normal anatomical measurements in cervical computerized tomography

    Energy Technology Data Exchange (ETDEWEB)

    Zaunbauer, W.; Daepp, S.; Haertel, M.

    1985-11-01

    Radiodiagnostically relevant normal values and variations for measurements of the cervical region, the arithmetical average and the standard deviation were determined from adequate computer tomograms on 60 healthy women and men, aged 20 to 83 years. The sagittal diameter of the prevertebral soft tissue and the lumina of the upper respiratory tract were evaluated at exactly defined levels between the hyoid bone and the incisura jugularis sterni. - The thickness of the aryepiglottic folds, the maximal sagittal and transverse diameters of the thyroid gland and the calibre of the great cervical vessels were defined. - To assess information about laryngeal function in computerized tomography, measurements of distances between the cervical spine and anatomical fixed points of the larynx and hypopharynx were made as well as of the degree of vocal cord movement during normal respiration and phonation.

  3. Effects of Extreme Obliquity Variations on the Habitability of Exoplanets

    Science.gov (United States)

    Armstrong, J. C.; Barnes, R.; Domagal-Goldman, S.; Breiner, J.; Quinn, T. R.; Meadows, V. S.

    2014-01-01

    We explore the impact of obliquity variations on planetary habitability in hypothetical systems with high mutual inclination. We show that large-amplitude, high-frequency obliquity oscillations on Earth-like exoplanets can suppress the ice-albedo feedback, increasing the outer edge of the habitable zone. We restricted our exploration to hypothetical systems consisting of a solar-mass star, an Earth-mass planet at 1 AU, and 1 or 2 larger planets. We verified that these systems are stable for 108 years with N-body simulations and calculated the obliquity variations induced by the orbital evolution of the Earth-mass planet and a torque from the host star. We ran a simplified energy balance model on the terrestrial planet to assess surface temperature and ice coverage on the planet's surface, and we calculated differences in the outer edge of the habitable zone for planets with rapid obliquity variations. For each hypothetical system, we calculated the outer edge of habitability for two conditions: (1) the full evolution of the planetary spin and orbit and (2) the eccentricity and obliquity fixed at their average values. We recovered previous results that higher values of fixed obliquity and eccentricity expand the habitable zone, but we also found that obliquity oscillations further expand habitable orbits in all cases. Terrestrial planets near the outer edge of the habitable zone may be more likely to support life in systems that induce rapid obliquity oscillations as opposed to fixed-spin planets. Such planets may be the easiest to directly characterize with space-borne telescopes.

  4. Effects of variation of fundamental constants from Big Bang to atomic clocks

    Science.gov (United States)

    Flambaum, Victor

    2004-05-01

    Theories unifying gravity with other interactions suggest temporal and spatial variation of the fundamental "constants" in expanding Universe. I discuss effects of variation of the fine structure constant, strong interaction, quark mass and gravitational constant. The measurements of these variations cover the lifespan of the Universe from few minutes after Big Bang to the present time and give controversial results. There are some hints for the variations in Big Bang nucleosynthesis, quasar absorption spectra and Oklo natural nuclear reactor data. A very promising method to search for the variation of the fundamental constants consists in comparison of different atomic clocks. A billion times enhancement of the variation effects happens in transitions between accidentally degenerate atomic energy levels.

  5. Effects of temperature variation on the SLC linac RF system

    Energy Technology Data Exchange (ETDEWEB)

    Decker, F.J.; Akre, R.; Byrne, M.; Farkas, Z.D.; Jarvis, H.; Jobe, K.; Koontz, R.; Mitchell, M.; Pennacchi, R.; Ross, M. [and others

    1995-06-01

    The rf system of the Stanford Linear Collider in California is subjected to daily temperature cycles of up to 15{degrees}C. This can result in phase variations of 15{degrees} at 3 GHz over the 3 km length of the main drive line system. Subsystems show local changes of the order of 3{degrees} over 100 meters. When operating with flat beams and normalized emittances of 0.3*10{sup {minus}5} m-rad in the vertical plane, changes as small as 0.5{degrees} perturb the wakefield tail compensation and make continuous tuning necessary. Different approaches to stabilization of the RF phases and amplitudes are discussed.

  6. The Main Technical Points of Thoracoscopic Anatomical Lung Segment Resection

    Directory of Open Access Journals (Sweden)

    Liang CHEN

    2016-06-01

    Full Text Available Thoracoscopic segmentectomy is technically much more meticulous than lobectomy, due to the complicated anotomical variations of segmental bronchi and vessels. Preoperative three-dimensional computed tomography bronchography and angiography, 3D-CTBA could reveal the anatomical structures and variations of the segmental bronchi/vessels and locate the pulmonary nodules, which is helpful for surgery planning. Preoperative nodule localization is of vital importance for thoracoscopic segmentectomy. Techniques involved in this procedure include dissection of the targeted arteries, bronchus and intra-segmental veins, retention of the inter-segmental veins, identification of the inter-segmental boarder with the inflation-deflation method and seperation of intra-segmental pulmonary tissues by electrotome and/or endoscopic staplers. The incision margin for malignant nodules should be at least 2 cm or the diameter of the tumor. Meanwhile, sampling of N1 and N2 station lymph nodes and intraoperative frozen section is also necessary. The complication rate of thoracoscopic segmentectomy is comparatively low. The anatomic relationship between pulmonary segments and lobes is that a lobe consists of several irregular cone-shaped segments with the inter-segmental veins lies between the segments. Our center has explored a method to separate pulmonary segments from the lobe on the basis of cone-shaped principle, and we named it “Cone-shaped Segmentectomy”. This technique could precisely decide and dissect the targeted bronchi and vessels, and anatomically separate the inter-segmental boarder, which ultimately achieve a completely anatomical segmentectomy.

  7. Anatomical structure of Polystichum Roth ferns rachises

    Directory of Open Access Journals (Sweden)

    Oksana V. Tyshchenko

    2012-03-01

    Full Text Available The morpho-anatomical characteristics of rachis cross sections of five Polystichum species is presented. The main and auxiliary anatomical features which help to distinguish investigated species are revealed.

  8. Variation in acrylamide concentration in French fries : effects of control measures in food service establishments

    OpenAIRE

    Sanny, M.A.I.

    2012-01-01

    The aim of this thesis was first to identify the major technological and managerial factors and to investigate their contribution to variation in acrylamide concentrations.  The second aim was to investigate the effect of technological and managerial control measures on the concentration and variation of acrylamide in the preparation of French fries in food service establishments (FSE).  The variation ininitial concentration of reducing sugars, variable frying conditions and food ha...

  9. The Effect of Diurnal Variations on Ionospheric Radio Occultations

    Science.gov (United States)

    Yelle, Roger V.; Koskinen, Tommi; Withers, Paul; Schinder, Paul J.; Moses, Julianne I.; Mueller-Wodarg, Ingo

    2016-10-01

    Radio occultations are a powerful technique for the study of atmospheres and ionospheres by planetary spacecraft. For missions to the outer solar system, the occultations always probe the terminator region of the planet. The analysis of radio occultations typically assumes symmetry along the ray path in the horizontal direction about the tangent point. While this is an excellent assumption for the neutral atmosphere where the scale length of horizontal gradients is large, it is suspect for the ionosphere where electron densities decrease rapidly from day to night. Diurnal variations in peak electron density are often several orders of magnitude and may occur over a region of a few degrees. We investigate the consequences of diurnal variations on ionospheric occultations with a ray tracing calculation for the angular deflection and frequency residual of the radio wave. The calculations are based on photochemical/diffusion models for the ionospheres of Saturn and Titan. Differences from analysis based on the assumption of horizontal symmetry are most pronounced in the bottom side ionosphere where chemical time constants are short.

  10. Fatty acid and triacylglycerol composition of the subcutaneous fat from iberian pigs fattened on the traditional feed: “Montanera”. effect of anatomical location and length of feeding

    Directory of Open Access Journals (Sweden)

    Narváez-Rivas, Mónica

    2009-07-01

    Full Text Available Fatty acid and triacylglycerol compositions of 200 samples of subcutaneous fat from two different anatomical locations (rump and adipose tissue covering the Biceps femoris muscle of Iberian purebred pigs reared on “Montanera” were determined. Significant differences were found for the majority fatty acids and for some triacylglycerol species (PPS, PLPo + MLO, PLO, PLL + PoLO, SOS, SOL, OLL among the two anatomical locations, being the rump location less saturated. The activity level of the key enzyme involved in lipogenesis differed (p Biceps femoris, increases faster than that of the subcutaneous fat covering a muscle with low oxidative metabolism, as Longissimus dorsi.Se ha determinado la composición de ácidos grasos y de triglicéridos en 200 muestras de grasa subcutánea procedentes de dos localizaciones anatómicas (rabadilla y tejido adiposo que recubre el músculo Biceps femoris de cerdos ibéricos puros alimentados en “Montanera”. Se encontraron diferencias significativas para la mayoría de ácidos grasos y para algunos triglicéridos PPS, PLPo + MLO, PLO, PLL + PoLO, SOS, SOL, OLL entre las dos localizaciones anatómicas, siendo la rabadilla la menos saturada. El nivel de actividad de la enzima involucrada en la lipogénesis defirió significativamente (p B. femoris, aumenta más rápidamente que la de la grasa subcutánea que recubre un músculo con bajo metabolismo oxidativo, como el Longissimus dorsi.

  11. Effect of compositional variation in plutonium on process shielding design

    Energy Technology Data Exchange (ETDEWEB)

    Brown, T.H.

    1997-11-01

    Radiation dose rate from plutonium with high {sup 239}Pu content varies with initial nuclidic content, radioactive decay time, and impurity elemental content. The two idealized states of old plutonium and clean plutonium, whose initial compositions are given, provide approximate upper and lower bounds on dose rate variation. Whole-body dose rates were calculated for the two composition states, using unshielded and shielded plutonium spheres of varying density. The dose rates from these variable density spheres are similar to those from expanded plutonium configurations encountered during processing. The dose location of 40 cm from the sphere center is representative of operator standoff for direct handling of plutonium inside a glove box. The results have shielding implications for glove boxes with only structurally inherent shielding, especially for processing of old plutonium in an expanded configuration. Further reduction in total dose rate by using lead to reduce photon dose rate is shown for two density cases representing compact and expanded plutonium configurations.

  12. The effect of lateral variations of friction on crustal faulting

    Directory of Open Access Journals (Sweden)

    M. Cocco

    1994-06-01

    Full Text Available We propose that lateral variations in fault friction control the heterogeneity of slip observed in large earthquakes, We model these variations using a rate and state-dependent friction law, where we differentiate velocity-weakening into strong and weak-seismic fields, and velocity-strengthening into compliant and viscous fields. The strong-seismic field comprises the seismic slip concentrations, or asperities. The two «intermediate» frictional fields, weak-seismic and compliant, modulate both the tectonic loading and the dynamic rupture process. During the interseismic period, the compliant and viscous regions slip aseismically while the strong-seismic regions remain locked, evolving into stress concentrations that fail only in main shocks. The weak-seismic regions contain most of the interseismic activity and aftershocks, but also «creep seismically», that is, most of the weak-seismic area slips aseismically, actuating the seismicity on the remaining area. This «mixed» frictional behavior can be obtained from a sufficiently heterogenous distribution for the critical slip distance. The interseismic slip provides an inherent rupture resistance: dynamic rupture fronts decelerate as they penetrate into these unloaded compliant or creeping weak-seismic areas, diffusing into broad areas of accelerated afterslip. Aftershocks occur in both the weak-seismic and compliant areas around the fault, but most of the stress is diffused through aseismic slip. Rapid afterslip on these peripheral areas can also produce aftershocks within the main shock rupture area, by reloading weak fault areas that slipped in the main shock and then healed. We test this frictional model by comparing the interevent seismicity and aftershocks to the coseismic slip distribution for the 1966 Parkfield, 1979 Coyote Lake, and 1984 Morgan Hill earthquakes.

  13. Effects of Wolbachia on mitochondrial DNA variation in populations of Athetis lepigone (Lepidoptera: Noctuidae) in China

    Science.gov (United States)

    Wolbachia are endosymbiotic bacteria that infect arthropods and incompatibility among strains can affect gene flow within host insect populations, that can result in significant host mitochondrial DNA (MtD) variation. The effects of Wolbachia infection on mtDNA variation was studied in Athetis lepi...

  14. Measures to anatomic variations of the colonic vessels in laparoscopic operations%腹腔镜结直肠癌根治术中结肠血管变异的应对措施

    Institute of Scientific and Technical Information of China (English)

    潘凯

    2013-01-01

    In laparoscopic colorectal resection,the poor blood supply of the anastomosis after tumor excision is difficult to be determined during the operations sometimes.The change in blood supply of the bowel is mainly due to the mesenteric anatomy and the operative techniques.The direct blood supply of colon is the marginal vessels in the mesentery.The integrity and patency of the marginal vessels determine the vitality of the bowel.However,the marginal vessels are different in diameter,pulsation or even discontinue in various areas,affecting the excision of the colon and following anastomosis.The most common three dangerous areas to anastomosis include:(1)area between ileocolic artery and right colonic artery;(2)area between middle colonic artery and left colonic artery-the Griffiths point.(3)area between the terminal branch of sigmoid colonic artery and superior rectal arterySudeck dangerous area.In laparoscopic colorectal resection,one should pay attention to protect the blood supply of the bowel and the marginal blood vessels,and be vigilant to the three vascular variations above mentioned.The vessels should be ligated accurately to ensure sufficient blood supply to the anastomosis and consequent normal healing of the rectal and colonic anastomosis.More attention should be paid to the elderly,morbid,and diabetic patients.If the safety of the anastomosis is unsure,prophylactic ileostomy should be performed.%在腹腔镜结直肠癌根治术中,当切除肿瘤后进行消化道重建时,远近端肠管有时会出现血运改变,术中难以对肠管生机进行判断.术中肠管血运改变主要与结肠系膜血管的解剖学因素和手术操作有关.结肠壁的直接血供来源是边缘血管弓,边缘血管弓的完整性、通畅性是决定肠管存活率的关键.然而,边缘血管弓在不同区段直径大小不等,搏动强弱不一,有时甚至中断,对术中结肠的切除吻合造成影响.最常见的3处吻合不全区域有:(1)回结肠动

  15. Perceptual effects of dialectal and prosodic variation in vowels

    Science.gov (United States)

    Fox, Robert Allen; Jacewicz, Ewa; Hatcher, Kristin; Salmons, Joseph

    2005-09-01

    As was reported earlier [Fox et al., J. Acoust. Soc. Am. 114, 2396 (2003)], certain vowels in the Ohio and Wisconsin dialects of American English are shifting in different directions. In addition, we have found that the spectral characteristics of these vowels (e.g., duration and formant frequencies) changed systematically under varying degrees of prosodic prominence, with somewhat different changes occurring within each dialect. The question addressed in the current study is whether naive listeners from these two dialects are sensitive to both the dialect variations and to the prosodically induced spectral differences. Listeners from Ohio and Wisconsin listened to the stimulus tokens [beIt] and [bɛt] produced in each of three prosodic contexts (representing three different levels of prominence). These words were produced by speakers from Ohio or from Wisconsin (none of the listeners were also speakers). Listeners identified the stimulus tokens in terms of vowel quality and indicated whether it was a good, fair, or poor exemplar of that phonetic category. Results showed that both phonetic quality decisions and goodness ratings were systematically and significantly affected by speaker dialect, listener dialect, and prosodic context. Implications of source and nature of ongoing vowel changes in these two dialects will be discussed. [Work partially supported by NIDCD R03 DC005560-01.

  16. The effect of intraspecific variation and heritability on community pattern and robustness.

    Science.gov (United States)

    Barabás, György; D'Andrea, Rafael

    2016-08-01

    Intraspecific trait variation is widespread in nature, yet its effects on community dynamics are not well understood. Here we explore the consequences of intraspecific trait variation for coexistence in two- and multispecies competitive communities. For two species, the likelihood of coexistence is in general reduced by intraspecific variation, except when the species have almost equal trait means but different trait variances, such that one is a generalist and the other a specialist consumer. In multispecies communities, the only strong effect of non-heritable intraspecific variation is to reduce expected species richness. However, when intraspecific variation is heritable, allowing for the possibility of trait evolution, communities are much more resilient against environmental disturbance and exhibit far more predictable trait patterns. Our results are robust to varying model parameters and relaxing model assumptions.

  17. Seasonal effect on the diurnal variation of the geomagnetic field registered in Huancayo Observatory

    CERN Document Server

    Rosales, Domingo

    2016-01-01

    In this article we study the seasonal effect on the diurnal variation of the geomagnetic field registered in the Huancayo Observatory, located in the Magnetic Equator, which is driven by "ionospheric currents" and its counterpart induced by "telluric currents". Huancayo Observatory has the highest amplitude in the diurnal variation, because of being in the Magnetic Equator and under the "Equatorial Electrojet". We present the pattern of seasonal variation in diurnal variation of components X, Y and Z, the same as confirmed by previous works since 1940. The effect of solar activity cycle of about 11 years in the diurnal variation is also confirmed; it is observed that amplitudes are greater in the maximum of solar activity.

  18. Anatomical variation of piriformis muscle as a cause of deep gluteal pain: diagnosis using MR neurography and treatment Variação anatômica do músculo piriforme como causa de dor glútea profunda: diagnóstico por neurografia RM e seu tratamento

    Directory of Open Access Journals (Sweden)

    Giancarlo Cavalli Polesello

    2013-01-01

    Full Text Available Female patient, 42 years old with a history of low back pain on the left for seventeen years in which the definitive diagnosis of the etiology of pain was evident after the completion of neurography magnetic resonance imaging of the sciatic nerve. In this test it was identified the presence of an anatomical variation in the relationship between the piriformis muscle and sciatic nerve. We discuss details of this imaging technique and its importance in the frames of refractory low back pain. We also describe the treatment given to the case.Paciente do sexo feminino, 42 anos, com histórico de lombociatalgia à esquerda havia 17 anos. O diagnóstico definitivo da etiologia da dor só foi evidenciado após a neurografia por ressonância magnética do ciático. Nesse exame identificou-se a presença de variação anatômica entre o músculo piriforme e o nervo ciático. Descrevemos detalhes sobre a técnica de imagem e sua importância nos quadros de lombociatalgia refratária, como também o tratamento instituído para o caso.

  19. Using Seismic Tomography to Estimate the Magnitude of Lateral Variation in effective Mantle Viscosity

    Science.gov (United States)

    Sammis, C.; Ivins, E.

    1994-01-01

    Recent tomographic views of mantle are used to estimate corresponding lateral variations in effective viscosity under the assumption that temperature fluctuations about spherically symmetric mean values are the sole source of shear wave velocity anomalies.

  20. Choroid plexus of the fourth ventricle: Review and anatomic study highlighting anatomical variations.

    Science.gov (United States)

    Tubbs, R Shane; Shoja, Mohammadali M; Aggarwal, Anjali; Gupta, Tulika; Loukas, Marios; Sahni, Daisy; Ansari, Shaheryar F; Cohen-Gadol, Aaron A

    2016-04-01

    Relatively few studies have been performed that analyze the morphology of the choroid plexus of the fourth ventricle. Due to the importance of this tissue as a landmark on imaging and during surgical intervention of the fourth ventricle, the authors performed a cadaveric study to better characterize this important structure. The choroid plexus of the fourth ventricle of 60 formalin fixed adult human brains was examined and measured. The horizontal distance from the midline to the lateral most point of the protruding tip of the horizontal limbs was measured. In the majority of the 60 brain specimens, right and left horizontal limbs of the choroid plexus were seen extending from the midline and protruding out of their respective lateral apertures of the fourth ventricle and into the subarachnoid space. However, on 3.3% of sides, there was absence of an extension into the foramen of Luschka and in one specimen, this lack of extension into the foramen of Luschka was bilateral. On two sides, there was discontinuity between the midline choroid plexus and the tuft of choroid just outside the foramen of Luschka. For specimens in which the choroid plexus did protrude through the foramen of Luschka (96.7%), these tufts were located anterior to the flocculus and inferolateral to the facial/vestibulocochlear nerve complex and posterosuperior to the glossopharyngeal/vagal/accessory complex. A thorough understanding of the normal and variant anatomy of the fourth ventricular choroid plexus is necessary for those who operate in, or interpret imaging of, this region.

  1. Sinonasal Anatomical Variants: CT and Endoscopy Study and Its Correlation with Extent of Disease.

    Science.gov (United States)

    Mendiratta, Vandana; Baisakhiya, Nitish; Singh, Dalbir; Datta, Ginni; Mittal, Amit; Mendiratta, Parveen

    2016-09-01

    To evaluate the incidence of anatomical variations in sinonasal area by nasal endoscopy and CT scan paranasal sinuses and to correlate the anatomical variations in sinonasal area with extent of disease. The present study was conducted on 40 patients of chronic sinusitis. All the patients underwent CT scan paranasal sinus axial and coronal view and nasal endoscopy. The most common anatomical variations were agger nasi cells (80 %), deviated nasal septum (72.5 %) and concha bullosa (47.5 %). Other anatomical variations seen in sinonasal region were uncinate process variations, paradoxical middle turbinate, haller cells, accessory ostia of maxillary sinus, multiseptated sphenoid. Osteomeatal unit (87.5 %) and maxillary sinuses (87.5 %) were the most commonly involved which was followed by anterior ethmoids (70 %), posterior ethmoids (50 %), frontal sinuses (32.5 %) and the sphenoids (20 %). Considering the results obtained, we believe that anatomical variations may increase the risk of sinus mucosal disease. We therefore, emphasize the importance of a careful evaluation of CT study in patients with persistent symptoms of chronic rhinosinusitis. PMID:27508139

  2. Effects of power variation on cycle performance during simulated hilly time-trials.

    Science.gov (United States)

    Wells, Marc S; Marwood, Simon

    2016-11-01

    It has previously been shown that cyclists are unable to maintain a constant power output during cycle time-trials on hilly courses. The purpose of the present study is therefore to quantify these effects of power variation using a mathematical model of cycling performance. A hypothetical cyclist (body mass: 70 kg, bicycle mass: 10 kg) was studied using a mathematical model of cycling, which included the effects of acceleration. Performance was modelled over three hypothetical 40-km courses, comprising repeated 2.5-km sections of uphill and downhill with gradients of 1%, 3%, and 6%, respectively. Amplitude (5-15%) and distance (0.31-20.00 km) of variation were modelled over a range of mean power outputs (200-600 W) and compared to sustaining a constant power. Power variation was typically detrimental to performance; these effects were augmented as the amplitude of variation and severity of gradient increased. Varying power every 1.25 km was most detrimental to performance; at a mean power of 200 W, performance was impaired by 43.90 s (±15% variation, 6% gradient). However at the steepest gradients, the effect of power variation was relatively independent of the distance of variation. In contrast, varying power in parallel with changes in gradient improved performance by 188.89 s (±15% variation, 6% gradient) at 200 W. The present data demonstrate that during hilly time-trials, power variation that does not occur in parallel with changes in gradient is detrimental to performance, especially at steeper gradients. These adverse effects are substantially larger than those previously observed during flat, windless time-trials.

  3. Brachial plexus variations in its formation and main branches

    OpenAIRE

    Valéria Paula Sassoli Fazan; André de Souza Amadeu; Adilson L. Caleffi; Omar Andrade Rodrigues Filho

    2003-01-01

    PURPOSE: The brachial plexus has a complex anatomical structure since its origin in the neck throughout its course in the axillary region. It also has close relationship to important anatomic structures what makes it an easy target of a sort of variations and provides its clinical and surgical importance. The aims of the present study were to describe the brachial plexus anatomical variations in origin and respective branches, and to correlate these variations with sex, color of the subjects ...

  4. Effects of Perceptual Variations on Number Comparison Tasks.

    Science.gov (United States)

    Kingma, Johannes; Loth, Franciska L.

    1984-01-01

    Investigates the performance of 502 children ranging in age from four years to six years, ten months, on two-choice and multiple-choice number comparison tasks, and explores the effects of perceptual manipulations of elements in the multiple-choice tasks. (RH)

  5. Stimulus Variation as a Means of Enhancing Punishment Effects.

    Science.gov (United States)

    Charlop, Marjorie H.; And Others

    1988-01-01

    The study examined effects of varied punishers (overcorrection, time-out, or a verbal "no" compared with the single presentation of one punisher (a loud noise) on occurrence of inappropriate behaviors in three developmentally delayed children (ages 5-6). Both formats produced a decrease in target behaviors, with the varied-punisher format slightly…

  6. Sex-specific genetic effects influence variation in body composition

    NARCIS (Netherlands)

    M.C. Zillikens (Carola); M. Yazdanpanah (Mojgan); L.M. Pardo Cortes (Luba); F. Rivadeneira Ramirez (Fernando); Y.S. Aulchenko (Yurii); B.A. Oostra (Ben); A.G. Uitterlinden (André); H.A.P. Pols (Huib); P. Tikka-Kleemola (Päivi)

    2008-01-01

    textabstractAims/hypothesis: Despite well-known sex differences in body composition it is not known whether sex-specific genetic or environmental effects contribute to these differences. Methods: We assessed body composition in 2,506 individuals, from a young Dutch genetic isolate participating in t

  7. ANATOMICAL PRINCIPLES BEHIND PRESERVATION OF LARYNGEAL NERVES DURING THYROIDECTOMY

    Directory of Open Access Journals (Sweden)

    O. Fabian

    2011-08-01

    Full Text Available This paper presents the anatomical principles behind preservation of inferior laryngeal nerve and of the external branch of superior laryngeal nerve during thyroidectomy. The embryological development of thyroid and recurrent laryngeal nerves explains the constant relationship between Zuckerkandl’s tuberculum and the recurrent laryngeal nerve, while anomalies in development of the aortic arches explain the presence of rare anatomical variants, with a high risk of nerve injury, of non-recurrent course of the inferior laryngeal nerve. Good knowledge of the relationship between the external branch of superior laryngeal nerve and the superior thyroid artery makes possible to avoid transection of this branch during ligature around superior thyroid artery and vein. Anatomical landmarks used to identify the recurrent laryngeal nerve (tracheo-oesophageal sulcus, the cross-over with the inferior thyroid artery, Berry’s ligament, Zuckerkandl’s tuberculum and variations in the extra-laryngeal branching of the nerve are discussed based on data from the literature. The anatomical variants when the inferior laryngeal nerve doesn’t have a recurrent course are also discussed

  8. The effect of cosmic ray intensity variations and geomagnetic disturbances on the physiological state of aviators

    Science.gov (United States)

    Papailiou, M.; Mavromichalaki, H.; Kudela, K.; Stetiarova, J.; Dimitrova, S.; Giannaropoulou, E.

    2011-09-01

    Over the last few years various researches have reached the conclusion that cosmic ray variations and geomagnetic disturbances are related to the condition of the human physiological state. In this study medical data regarding 4018 Slovak aviators were analyzed in relation to daily variations of cosmic ray and geomagnetic activity. Specifically daily data concerning mean values of heart rate which were registered during the medical examinations of the Slovak aviators, were related to daily variations of cosmic ray intensity, as measured by the Neutron Monitor Station on Lomnicky Stit (http://neutronmonitor.ta3.sk/realtime.php3) and the high resolution neutron monitor database (http://www.nmdb.eu) and daily variations of Dst and Ap geomagnetic indices. All subjects were men in good health of age 18-60 yrs. This particular study refers to the time period from 1 January 1994 till 31 December 2002. Statistical methods were applied to establish a statistical significance of the effect of geomagnetic activity levels and cosmic ray intensity variations on the aforementioned physiological parameters for the whole group. The Pearson r-coefficients were calculated and the Analysis of Variance (ANOVA) method was applied to establish the statistical significance levels (p-values) of the effect of geomagnetic activity and cosmic ray intensity variations on heart rate up to three days before and three days after the respective events. Results show that there is an underlying effect of geomagnetic activity and cosmic ray intensity variations on the cardiovascular functionality.

  9. Digital imaging in anatomic pathology.

    Science.gov (United States)

    O'Brien, M J; Sotnikov, A V

    1996-10-01

    Advances in computer technology continue to bring new innovations to departments of anatomic pathology. This article briefly reviews the present status of digital optical imaging, and explores the directions that this technology may lead over the next several years. Technical requirements for digital microscopic and gross imaging, and the available options for image archival and retrieval are summarized. The advantages of digital images over conventional photography in the conference room, and the usefulness of digital imaging in the frozen section suite and gross room, as an adjunct to surgical signout and as a resource for training and education, are discussed. An approach to the future construction of digital histologic sections and the computer as microscope is described. The digital technologic applications that are now available as components of the surgical pathologist's workstation are enumerated. These include laboratory information systems, computerized voice recognition, and on-line or CD-based literature searching, texts and atlases and, in some departments, on-line image databases. The authors suggest that, in addition to these resources that are already available, tomorrow's surgical pathology workstation will include network-linked digital histologic databases, on-line software for image analysis and 3-D image enhancement, expert systems, and ultimately, advanced pattern recognition capabilities. In conclusion, the authors submit that digital optical imaging is likely to have a significant and positive impact on the future development of anatomic pathology. PMID:8853053

  10. Anatomical variation of vertebral artery at the craniovertebral junction in patients with occipitalization of the atlas: radiographic study using three-dimentional CT angiography%寰枕融合患者椎动脉走行的CT血管成像研究及其临床意义

    Institute of Scientific and Technical Information of China (English)

    王兴文; 陈赞; 许平; 吴浩; 菅凤增

    2011-01-01

    Objective To study the anatomical variation of vertebral artery (VA) at the craniovertebral junction (CVJ) in patients with occipitalization of the atlas. Methods Through reviewingthe image studies of 48 patients with occipitalization of the atlas admitted to Department of Neurosurgery, Xuanwu Hospital from January 2007 to October 2010, the anatomical characteristics of VA were studied retrospectively. Results According to the branches and anatomical course of VA, 48 patients (96 sides) were divided into 5 types. Type 1: the VA is single trunk, running between the occipitalized atlantal posterior arch and axial plate (19 sides, 19.79%); type 2: single trunk VA runs through a bony canal between the assimilated atlas and occipital cranium (43 sides, 44.79%); type 3: single trunk VA runs between the normal occipital cranium and atlantal posterior arch (29 sides, 30.21%); type 4: VA has a fenestration, with one branch running below the occipitalized atlantal posterior arch and the other branch running above the atlantal posterior arch (3 sides, 3.13%), 2 branches merge as one VA trunk after entering into the dura; type 5: hypogenesis or agenesis of VA (2 sides, 2.08%). Conclusion The vertebral artery has a high rate of anatomical variation in patients with assimilation of the atlas. The risk to be injured is high for type 1 and type 4 variations during surgical dissection. For type 2 and type 3, careful subperiosteal dissection can decrease the risk. Preoperative computed tomography (CT) angiography combined with bone reconstruction can provide important information in the preoperative evaluation, thus decrease surgical risk.%目的 观察先天性寰枕融合患者椎动脉走行的解剖学特征及其在颅颈交界区后路内固定手术中的临床意义.方法 回顾自2007年1月-2010年10月施行CT血管造影检查的48例先天性寰枕融合患者诊断与治疗经过,观察分析其椎动脉解剖走行特点.结果 根据椎动脉分支和行程,48

  11. The Effect of Climatic Variations on Agricultural Risk

    OpenAIRE

    Parry, M.L.; Carter, T.R.

    1984-01-01

    The thesis of this paper is that impacts from climatic change can be evaluated effectively as changes in the frequency of short-term, anomalous climatic events. These can then be expressed as changes in the level of risk of impact from climatic extremes. To evaluate this approach, the risk of crop failure resulting from low levels of accumulated temperature is assessed for oats farming in southern Scotland. Annual accumulated temperatures are calculated for the 323-year long temperature recor...

  12. Stimulus variation as a means of enhancing punishment effects.

    OpenAIRE

    Charlop, M H; Burgio, L D; Iwata, B A; Ivancic, M T

    1988-01-01

    We compared the effects of varied punishers (presentation of one of three available punishers) with the single presentation of one of the punishers on the occurrence of inappropriate behaviors with three developmentally delayed children. Two children were presented with varied-punisher conditions in which either overcorrection, time-out, or a verbal "no" was presented contingent upon inappropiate behavior. A loud noise was substituted for overcorrection for a third child. Results of the multi...

  13. Effect of four-dimensional variational data assimilation in case of nonlinear instability

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The effect of four-dimensional variational data assimilation on the reduction of the forecast errors is investigated for both stable and unstable flows. Numerical results show that the effect is generally positive. Particularly,its effect is much more significant in the presence of nonlinear instability

  14. Recent Earth Oblateness Variations: Unraveling Climate and Postglacial Rebound Effects

    Science.gov (United States)

    Dickey, Jean O.; Marcus, Steven L.; de Viron, Olivier; Fukumori, Ichiro

    2002-12-01

    Earth's dynamic oblateness (J2) has been decreasing due to postglacial rebound (PGR). However, J2 began to increase in 1997, indicating a pronounced global-scale mass redistribution within Earth's system. We have determined that the observed increases in J2 are caused primarily by a recent surge in subpolar glacial melting and by mass shifts in the Southern, Pacific, and Indian oceans. When these effects are removed, the residual trend in J2 (-2.9 x 10-11 year-1) becomes consistent with previous estimates of PGR from satellite and eclipse data. The climatic significance of these rapid shifts in glacial and oceanic mass, however, remains to be investigated.

  15. The effects of goal variation on adult physical activity behaviour.

    Science.gov (United States)

    Moon, Dal-Hyun; Yun, Joonkoo; McNamee, Jeff

    2016-10-01

    The purposes of this study were to examine the effects of varying levels of goals on increasing daily steps and the frequency of goal achievement among middle-aged adults. Ninety-six adults participated in a randomised control study. Participants were randomly assigned to five different step goal groups: (1) Easy (n = 19), (2) Medium (n = 19), (3) Difficult (n = 19), (4) Do-your-best (n = 19), and (5) No goal (n = 20) based on previous research. The participants wore a pedometer and were asked to reach a pre-established goal during the experimental period. In order to examine the effectiveness of the goal difficulty, (a) an average number of steps taken by different goal conditions and (b) the number of days meeting the assigned goal were tested. A one-way ANCOVA revealed significant step count differences among goal groups. Post hoc analyses indicated that the change in step count in both the Medium and Difficult goal groups was significantly greater than the remaining groups. However, there was no significant difference between the medium and difficult goal conditions. In addition, a one-way ANOVA indicated that there were no significant differences in the frequency of goal achievement among the Easy, Medium, and Difficult goal groups. Results suggest that when promoting physical activity through increasing step counts, researchers and clinicians should design goals that are specific and challenging. PMID:26860430

  16. Variations in effective compensation depth across Aphrodite Terra, Venus

    International Nuclear Information System (INIS)

    Aphrodite Terra is the largest elevated terrain on Venus and it serves as a focal point in current discussions of global tectonic style. Using the topography and gravity data acquired by the Pioneer Venus Orbiter (PVO) the authors have estimated an effective depth of Airy compensation for each of 75 orbital arcs that provide fairly uniform areal coverage of the entire province. The most pronounced pattern that emerges is a general increase in compensation depth to the east. The most rapid change occurs near 135 degree; the average west of there is 70 km, while the average to the east is 230 km. Superimposed on this larger trend are five distinctive regional patterns, four well defined peaks and one interval of widely scattered and poorly constrained depths. The maxima in compensation depth are well correlated with regional topographic highs. While these observations are easily reconciled with the general notion that Aphrodite is a region of crustal divergence, the great depth of compensation is difficult to accord with the more specific suggestion that Aphrodite is a terrestrial type divergent plate margin. The alternative suggestion that Aphrodite, and the other equatorial highlands on Venus, are surface manifestations of hot upwelling mantle plumes is consistent both with the great depths of compensation and with the pattern of regional peaks and intervening troughs. The broader scale increase in effective depth of compensation from west to east is more enigmatic, but it might reflect an age progression of the plumes

  17. Variation of kinetic isotope effect in multiple proton transfer reactions

    Indian Academy of Sciences (India)

    B Saritha; M Durga Prasad

    2012-01-01

    Recently, we had suggested that the motion along the promoter mode in the first part of the IRC of proton transfer reaction enhances the delocalization of electrons on the acceptor atom into the * orbital of the donor-hydrogen covalent bond, and as a consequence weakens it. This leads to a reduction of the barrier to the proton transfer as well as the stretching frequency of donor-hydrogen bond. An extension of this to the concerted multiple proton transfer reactions implies that the kinetic isotope effect in such reaction depends exponentially on the number of protons that are being transferred. Computational evidence on three systems, (HF)3, formic acid dimer, and (H2O) clusters is provided to support this assertion.

  18. Effect of component variations on the gate fidelity in linear optical networks

    Science.gov (United States)

    Crickmore, Jonathan; Frazer, Jonathan; Shaw, Scott; Kok, Pieter

    2016-08-01

    We investigate the effect of variations in beam-splitter transmissions and path-length differences in the nonlinear sign gate that is used for linear optical quantum computing. We identify two implementations of the gate and show that the sensitivity to variations in their components differs significantly between them. Therefore, circuits that require a precision implementation will generally benefit from additional circuit analysis of component variations to identify the most practical implementation. We suggest possible routes to efficient circuit analysis in terms of quantum parameter estimation.

  19. γ- Irradiation Effect: Variation of Photosynthetic Activity of Euglena

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Objective To study the effects of gamma-ray irradiation on carbon fixation (Specific production rate: SPR), CO2 utilization efficiency (CUE) and electron transfer rate (ETR) in the photosynthetic flagellate Euglena gracilis strain Z in a dose-response dependent manner. Methods Euglena cells were cultured in an inorganic nutrient medium containing ammonium chloride or proteose peptone. Cells were exposed to gamma-ray at 5 doses (0, 100, 250, 350, 500 Gy for water). Five days after irradiation, three photosynthetic activities were measured. SPR, which is a carbon uptake rate per unit carbon mass, was determined by 13C tracer methodology. CUE was evaluated using a relation of carbon isotope fractionation in Calvin cycle. ETR in photosystem II (PS II) was measured by a chlorophyll fluorescence analysis. Results Even at a dose of 500 Gy, 80 % of ETR of the non-irradiated control (0 Gy) was sustained, while SPR and CUE were about half the level in the non-irradiated control at 500 Gy. Furthermore, the dose response of ETR was considerably different from the others. Conclusion Our findings suggest that not only PS II but also the Calvin cycle in the photosynthetic system is affected by gamma ray irradiation.

  20. Variations in impact effects among IIIE iron meteorites

    Science.gov (United States)

    Breen, John P.; Rubin, Alan E.; Wasson, John T.

    2016-09-01

    Group-IIIE iron meteorites can be ordered into four categories reflecting increasing degrees of shock alteration. Weakly shocked samples (Armanty, Colonia Obrera, Coopertown, Porto Alegre, Rhine Villa, Staunton, and Tanokami Mountain) have haxonite within plessite, unrecrystallized kamacite grains containing Neumann lines or possessing the ɛ structure, and sulfide inclusions typically consisting of polycrystalline troilite with daubréelite exsolution lamellae. The only moderately shocked sample is NWA 4704, in which haxonite has been partially decomposed to graphite; the majority of the kamacite in NWA 4704 is recrystallized, and its sulfide inclusions were partly melted. Strongly shocked samples (Cachiyuyal, Kokstad, and Paloduro) contain graphite and no haxonite, suggesting that pre-existing haxonite fully decomposed. Also present in these rocks are recrystallized kamacite and melted troilite. Residual heat from the impact caused annealing and recrystallization of kamacite as well as the decomposition of haxonite into graphite. Severely shocked samples (Aliskerovo and Willow Creek) have sulfide-rich assemblages consisting of fragmental and subhedral daubréelite crystals, 1-4 vol% spidery troilite filaments, and 30-50 vol% low-Ni kamacite grains, some of which contain up to 6.0 wt% Co; haxonite in these inclusions has fully decomposed to graphite. The wide range of impact effects in IIIE irons is attributed to one or more major collision(s) on the parent asteroid that affected different group members to different extents depending on their proximity to the impact point.

  1. Effect of Interplanetary Transients on Cosmic Ray Anisotropic Variations

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In the present work the cosmic ray intensity data recorded with ground-based neutron monitor at Deep River has investigated taking into account the associated interplanetary magnetic field and solar wind plasma data during 1981-1994. A large number of days having abnormally high/low amplitudes for successive number of five or more days as compared to annual average amplitude of diurnal anisotropy have been taken as high/low amplitude anisotropic wave train events (HAE/LAE). The amplitude of the diurnal anisotropy of these events is found to increase on the days of magnetic cloud as compared to the days prior to the event and it found to decrease during the later period of the event as the cloud passes the Earth. The High-Speed Solar Wind Streams (HSSWS) do not play any significant role in causing these types of events. The interplanetary disturbances (magnetic clouds) are also effective in producing cosmic ray decreases. Hα solar flares have a good positive correlation with both amplitude and direction of the anisotropy for HAEs,whereas PMSs have a good positive correlation with both amplitude and direction of the anisotropy for LAEs.The source responsible for these unusual anisotropic wave trains in CR has been proposed.

  2. Explaining growth variation over large spatial scales: Effects of temperature and food on walleye growth

    DEFF Research Database (Denmark)

    Mosgaard, Thomas; Venturelli, Paul; Lester, Nigel P.;

    2012-01-01

    for among-lake variation in growth (e.g., food and temperature) has proved very difficult. Here, we use length at age and temperature data from hundreds of water bodies between 44⁰N to 53⁰N latitude to explain variation in immature growth of walleye (Sander vitreus), one of the most economically valuable......-dependent effects are swamped by differences in productivity...

  3. On the limits of toxicant-induced tolerance testing: cotolerance and response variation of antibiotic effects.

    OpenAIRE

    Schmitt, Heike; Martinali, Bennie; Beelen, Patrick van; Seinen, Willem

    2006-01-01

    Pollution-induced community tolerance (PICT) as an ecotoxicological test system has been claimed to detect pollutant effects highly specifically and sensitively. However, the specificity might be limited by the occurrence of cotolerance. Another limitation of the application of any ecotoxicological test system lies in variation of the measured responses. We tested the variation and the occurrence of cotolerance experimentally, using antibiotics as toxicants, soil microcosms as microbial commu...

  4. Social carry-over effects on non-social behavioral variation: mechanisms and consequences

    Directory of Open Access Journals (Sweden)

    Petri Toivo Niemelä

    2015-05-01

    Full Text Available The field of animal personality is interested in decomposing behaviors into different levels of variation, with its present focus on the ecological and evolutionary causes and consequences of expressed variation. Recently the role of the social environment, i.e. social partners, has been suggested to affect behavioral variation and induce selection on animal personality. Social partner effects exist because characters of social partners (e.g. size, behavior, affect the behavioral expression of a focal individual. Here, we 1 first review the proximate mechanisms underlying the social partner effects on behavioral expression and the timescales at which such effects might take place. We then 2 discuss how within- and among-individual variation in single behaviors and covariation between multiple behaviors, caused by social partners, can carry-over to non-social behaviors expressed outside the social context. Finally, we 3 highlight evolutionary consequences of social carry-over effects to non-social behaviors and 4 suggest study designs and statistical approaches which can be applied to study the nature and evolutionary consequences of social carry-over effects on non-social behaviors. Understanding the proximate mechanisms underpinning the social partner effects is important since it opens a door for deeper understanding of how social environments can affect behavioral variation and covariation at multiple levels, and the evolution of non-social behaviors (i.e. exploration, activity, boldness that are affected by social interactions.

  5. Image fusion in dual energy computed tomography for detection of various anatomic structures - Effect on contrast enhancement, contrast-to-noise ratio, signal-to-noise ratio and image quality

    Energy Technology Data Exchange (ETDEWEB)

    Paul, Jijo, E-mail: jijopaul1980@gmail.com [Department of Diagnostic Radiology, Goethe University Hospital, Theodor-Stern-Kai 7, 60590 Frankfurt am Main (Germany); Department of Biophysics, Goethe University, Max von Laue-Str.1, 60438 Frankfurt am Main (Germany); Bauer, Ralf W. [Department of Diagnostic Radiology, Goethe University Hospital, Theodor-Stern-Kai 7, 60590 Frankfurt am Main (Germany); Maentele, Werner [Department of Biophysics, Goethe University, Max von Laue-Str.1, 60438 Frankfurt am Main (Germany); Vogl, Thomas J. [Department of Diagnostic Radiology, Goethe University Hospital, Theodor-Stern-Kai 7, 60590 Frankfurt am Main (Germany)

    2011-11-15

    Objective: The purpose of this study was to evaluate image fusion in dual energy computed tomography for detecting various anatomic structures based on the effect on contrast enhancement, contrast-to-noise ratio, signal-to-noise ratio and image quality. Material and methods: Forty patients underwent a CT neck with dual energy mode (DECT under a Somatom Definition flash Dual Source CT scanner (Siemens, Forchheim, Germany)). Tube voltage: 80-kV and Sn140-kV; tube current: 110 and 290 mA s; collimation-2 x 32 x 0.6 mm. Raw data were reconstructed using a soft convolution kernel (D30f). Fused images were calculated using a spectrum of weighting factors (0.0, 0.3, 0.6 0.8 and 1.0) generating different ratios between the 80- and Sn140-kV images (e.g. factor 0.6 corresponds to 60% of their information from the 80-kV image, and 40% from the Sn140-kV image). CT values and SNRs measured in the ascending aorta, thyroid gland, fat, muscle, CSF, spinal cord, bone marrow and brain. In addition, CNR values calculated for aorta, thyroid, muscle and brain. Subjective image quality evaluated using a 5-point grading scale. Results compared using paired t-tests and nonparametric-paired Wilcoxon-Wilcox-test. Results: Statistically significant increases in mean CT values noted in anatomic structures when increasing weighting factors used (all P {<=} 0.001). For example, mean CT values derived from the contrast enhanced aorta were 149.2 {+-} 12.8 Hounsfield Units (HU), 204.8 {+-} 14.4 HU, 267.5 {+-} 18.6 HU, 311.9 {+-} 22.3 HU, 347.3 {+-} 24.7 HU, when the weighting factors 0.0, 0.3, 0.6, 0.8 and 1.0 were used. The highest SNR and CNR values were found in materials when the weighting factor 0.6 used. The difference CNR between the weighting factors 0.6 and 0.3 was statistically significant in the contrast enhanced aorta and thyroid gland (P = 0.012 and P = 0.016, respectively). Visual image assessment for image quality showed the highest score for the data reconstructed using the

  6. Variations: Darwin's finches, sea barnacles and the side effects of antidepressants.

    Science.gov (United States)

    Lieb, Julian

    2008-01-01

    "It may metaphorically be said," Darwin wrote, "that natural selection is daily and hourly scrutinizing, throughout the world, the slightest variations; rejecting those that are bad, preserving and adding up all that are good; silently and insensibly working, whenever and wherever opportunity offers..." Variation is a principle of nature, without which natural selection could not operate, and life exist. Darwin believed that natural selection would make nature "more and more diversified." Variation occurs in the clutch sizes of birds, the color of hair and skin, the annual temperature, in language and speech, the direction of local Magnetic North and True North, and the variation of pathogens (antigenic variation). Antidepressants act as probes, burrowing into the deepest recesses of cells, and signaling physiological and pathological information to observers. They have at least forty side effects that are not only variations, but often paradoxes that would have fascinated Charles Darwin, who had the keenest interest in the variation of the beaks of finches and in sea barnacles. PMID:17681431

  7. Estudo das relações anatômicas e suas variações entre o nervo ciático e o músculo piriforme Study on anatomical relationships and variations between the sciatic nerve and piriform muscle

    Directory of Open Access Journals (Sweden)

    EJD Vicente

    2007-06-01

    Full Text Available CONTEXTO: A síndrome do músculo piriforme pode ter como causa a passagem anormal do nervo ciático ou de uma de suas partes pelo ventre do músculo piriforme. OBJETIVO: Analisar as relações anatômicas e métricas entre o músculo piriforme e o nervo ciático, contribuindo com o conhecimento anátomo-clínico da região glútea. MÉTODO: Foram utilizados 20 cadáveres adultos de ambos os sexos. O nervo ciático e o músculo piriforme foram dissecados, medidos e fotodocumentados. RESULTADOS: Observou-se que 85% das 40 regiões glúteas apresentaram o nervo como tronco único, passando pela borda inferior do músculo piriforme, e 15% mostraram uma variação bilateral, caracterizada pela passagem do nervo fibular comum através do músculo piriforme. Os dados obtidos não revelaram diferenças estatisticamente significantes.CONTEXT: Piriform muscle syndrome can be caused by abnormal passage of the sciatic nerve or one of its parts through the belly of the piriform muscle. OBJECTIVE: To analyze the anatomical and measurement relationships between the piriform muscle and the sciatic nerve in order to contribute towards better anatomoclinical understanding of the gluteal region. METHOD: Twenty adult cadavers of both sexes were used. The sciatic nerve and piriform muscle were dissected, measured and photodocumented. RESULTS: The sciatic nerve was seen to be a single trunk passing through the lower margin of the piriform muscle in 85% of the 40 gluteal regions, and 15% showed bilateral variation characterized by the passage of the common fibular nerve through the piriform muscle. The data obtained did not show any statistically significant differences.

  8. Disk Temperature Variations and Effects on the Snow Line in the Presence of Small Protoplanets

    CERN Document Server

    Jang-Condell, H; Jang-Condell, Hannah; Sasselov, Dimitar D.

    2004-01-01

    We revisit the computation of a "snow line" in a passive protoplanetary disk during the stage of planetesimal formation. We examine how shadowing and illumination in the vicinity of a planet affects where in the disk ice can form, making use of our method for calculating radiative transfer on disk perturbations with some improvements on the model. We adopt a model for the unperturbed disk structure that is more consistent with observations and use opacities for reprocessed dust instead of interstellar medium dust. We use the improved disk model to calculate the temperature variation for a range of planet masses and distances and find that planets at the gap-opening threshold can induce temperature variations of up to +/-30%. Temperature variations this significant may have ramifications for planetary accretion rates and migration rates. We discuss in particular the effect of temperature variations near the sublimation point of water, since the formation of ice can enhance the accretion rate of disk material o...

  9. An Anatomically Validated Brachial Plexus Contouring Method for Intensity Modulated Radiation Therapy Planning

    Energy Technology Data Exchange (ETDEWEB)

    Van de Velde, Joris, E-mail: joris.vandevelde@ugent.be [Department of Anatomy, Ghent University, Ghent (Belgium); Department of Radiotherapy, Ghent University, Ghent (Belgium); Audenaert, Emmanuel [Department of Physical Medicine and Orthopedic Surgery, Ghent University, Ghent (Belgium); Speleers, Bruno; Vercauteren, Tom; Mulliez, Thomas [Department of Radiotherapy, Ghent University, Ghent (Belgium); Vandemaele, Pieter; Achten, Eric [Department of Radiology, Ghent University, Ghent (Belgium); Kerckaert, Ingrid; D' Herde, Katharina [Department of Anatomy, Ghent University, Ghent (Belgium); De Neve, Wilfried [Department of Radiotherapy, Ghent University, Ghent (Belgium); Van Hoof, Tom [Department of Anatomy, Ghent University, Ghent (Belgium)

    2013-11-15

    Purpose: To develop contouring guidelines for the brachial plexus (BP) using anatomically validated cadaver datasets. Magnetic resonance imaging (MRI) and computed tomography (CT) were used to obtain detailed visualizations of the BP region, with the goal of achieving maximal inclusion of the actual BP in a small contoured volume while also accommodating for anatomic variations. Methods and Materials: CT and MRI were obtained for 8 cadavers positioned for intensity modulated radiation therapy. 3-dimensional reconstructions of soft tissue (from MRI) and bone (from CT) were combined to create 8 separate enhanced CT project files. Dissection of the corresponding cadavers anatomically validated the reconstructions created. Seven enhanced CT project files were then automatically fitted, separately in different regions, to obtain a single dataset of superimposed BP regions that incorporated anatomic variations. From this dataset, improved BP contouring guidelines were developed. These guidelines were then applied to the 7 original CT project files and also to 1 additional file, left out from the superimposing procedure. The percentage of BP inclusion was compared with the published guidelines. Results: The anatomic validation procedure showed a high level of conformity for the BP regions examined between the 3-dimensional reconstructions generated and the dissected counterparts. Accurate and detailed BP contouring guidelines were developed, which provided corresponding guidance for each level in a clinical dataset. An average margin of 4.7 mm around the anatomically validated BP contour is sufficient to accommodate for anatomic variations. Using the new guidelines, 100% inclusion of the BP was achieved, compared with a mean inclusion of 37.75% when published guidelines were applied. Conclusion: Improved guidelines for BP delineation were developed using combined MRI and CT imaging with validation by anatomic dissection.

  10. Morphological and anatomical characteristics of Scots pine needles under industrial pollution impact of Krasnoyarsk city

    Directory of Open Access Journals (Sweden)

    L. N. Skripal’shchikova

    2016-06-01

    Full Text Available The changes of morphological and anatomical characteristics of Scots pine needles as well as their fluctuating asymmetry (FA were studied in pine stands under the influence of industrial emissions of Krasnoyarsk. Observations were made in forest-steppe zone on windward pine forest edges in the conditions of long-term anthropogenic effect. Background site was pine stand 100 km from the city outside the direction of wind pollution. The investigations were carried out in 2013–2014 in pure pine stands of grass type, V–VI class of age. For every model tree the needle lengths in pairs were measured, as well as the cross section area of needle, area of central cylinder and conducting bindles areas and the number of resin canals. Indices of fluctuating asymmetry were calculated by method of Palmer and Strobeck (1986. The content of copper, nickel, zinc, cobalt, aluminum, cadmium, lead, fluorine and sulfur were analyzed in needle samples in parallel. The dimensions of needles and its internal structure elements showed the tendency to decrease under the influence of urban industrial emissions in comparison with background sites. On the other hand, there were adaptations of morphological and anatomical parameters of physiologically active needles to the changing environment through a compensatory mechanism. Fluctuating asymmetry indices of needles parameters were found to vary both in technogenic conditions and background ones. The variations were caused by abiotic factors of habitats and levels of technogenic loadings in these stands. Correlation analysis revealed relations between concentrations of heavy metals, aluminum and fluorine and morphological and anatomical characteristics of needles and FA indices. The most unfavorable effects were produced by high concentrations of lead and fluorine.

  11. Brain Morphometry Using Anatomical Magnetic Resonance Imaging

    Science.gov (United States)

    Bansal, Ravi; Gerber, Andrew J.; Peterson, Bradley S.

    2008-01-01

    The efficacy of anatomical magnetic resonance imaging (MRI) in studying the morphological features of various regions of the brain is described, also providing the steps used in the processing and studying of the images. The ability to correlate these features with several clinical and psychological measures can help in using anatomical MRI to…

  12. Are the Genitalia of Anatomical Dolls Distorted?

    Science.gov (United States)

    Bays, Jan

    1990-01-01

    To determine whether the genitalia of anatomical dolls are disproportionately large and may suggest sexual activity to children who have not been abused, the genitalia and breasts of 17 sets of anatomical dolls were measured. When the measurements were extrapolated to adult human proportions, the sizes were not found to be exaggerated. (Author/JDD)

  13. The variation characteristics and effect factors of surface ozone concentration in the Taklimakan Desert hinterland

    Institute of Scientific and Technical Information of China (English)

    XinChun Liu; YuTing Zhong; Qing He; YanMei Peng; XingHua Yang; Ali Mamtimin; Wen Huo

    2014-01-01

    Based on automatic continuous surface ozone concentration observation data from June 10, 2010 to March 20, 2012 in the Taklimakan Desert hinterland, combined with corresponding meteorological data, the temporal, seasonal and daily variation characteristics of surface ozone concentrations under different weather conditions were analyzed. At the same time, the main fac-tors affecting ozone variation are discussed. Results show that:(1) Daily variation of ozone concentration was characterized by one obvious peak, with gentle changes during the night and dramatic changes during the day. The lowest concentration was at 09:00 and the highest was at 18:00. Compared to urban areas, there was a slight time delay. (2) Ozone concentration variation had a weekend effect phenomenon. Weekly variation of ozone concentration decreased from Monday to Wednesday with the lowest in Wednesday, and increased after Thursday with the highest in Sunday. (3) The highest monthly average concentration was 89.6μg/m3 in June 2010, and the lowest was 32.0μg/m3 in January 2012. Ozone concentration reduced month by month from June to December in 2010. (4) Ozone concentration in spring and summer was higher than in autumn and winter. The variation trend agreed with those in other large and medium-sized cities. (5) Under four different types of weather, daily ozone concentration var-ied most dramatically in sunny days, followed by slight variation in rain days, and varied gently in cloudy days. Ozone concentra-tion varied inconspicuously before a sandstorm appearance, and dropped rapidly at the onset of a sandstorm. (6) Daily variation of radiation was also characterized by a single peak, and the variation was significantly earlier than ozone concentration variation. Sun radiation intensity had a direct influence on the photochemical reaction speed, leading to variation of ozone concentration. (7) Daily average ozone concentration in dust weather was higher than in slight rain and clear days. The

  14. TECHNIQUE AND SURGICAL OUTCOMES OF ANATOMICAL LIVER RESECTIONS FOR COLORECTAL CANCER LIVER METASTASES

    Directory of Open Access Journals (Sweden)

    D. V. Sidorov

    2013-01-01

    Full Text Available Technique and surgical outcomes of anatomical liver resections using ERBEJET2® water-jet dissector were described. Overall 98 patients with colorectal cancer liver metastases were included in this study. In 43 patients resections were performed using water-jet dissection technique. Water-jet dissection seems to be safe and effective technique for anatomical liver resections.

  15. Femoral rotation unpredictably affects radiographic anatomical lateral distal femoral angle measurements

    DEFF Research Database (Denmark)

    Miles, James Edward

    2016-01-01

    Objective: To describe the effects of internal and external femoral rotation on radiographic measurements of the anatomical lateral distal femoral angle (a-LDFA) using two methods for defining the anatomical proximal femoral axis (a-PFA). Methods: Digital radiographs were obtained of 14 right...

  16. Fabrication and Assessment of 3D Printed Anatomical Models of the Lower Limb for Anatomical Teaching and Femoral Vessel Access Training in Medicine

    Science.gov (United States)

    O'Reilly, Michael K.; Reese, Sven; Herlihy, Therese; Geoghegan, Tony; Cantwell, Colin P.; Feeney, Robin N. M.; Jones, James F. X.

    2016-01-01

    For centuries, cadaveric dissection has been the touchstone of anatomy education. It offers a medical student intimate access to his or her first patient. In contrast to idealized artisan anatomical models, it presents the natural variation of anatomy in fine detail. However, a new teaching construct has appeared recently in which artificial…

  17. Two levels ARIMAX and regression models for forecasting time series data with calendar variation effects

    Science.gov (United States)

    Suhartono, Lee, Muhammad Hisyam; Prastyo, Dedy Dwi

    2015-12-01

    The aim of this research is to develop a calendar variation model for forecasting retail sales data with the Eid ul-Fitr effect. The proposed model is based on two methods, namely two levels ARIMAX and regression methods. Two levels ARIMAX and regression models are built by using ARIMAX for the first level and regression for the second level. Monthly men's jeans and women's trousers sales in a retail company for the period January 2002 to September 2009 are used as case study. In general, two levels of calendar variation model yields two models, namely the first model to reconstruct the sales pattern that already occurred, and the second model to forecast the effect of increasing sales due to Eid ul-Fitr that affected sales at the same and the previous months. The results show that the proposed two level calendar variation model based on ARIMAX and regression methods yields better forecast compared to the seasonal ARIMA model and Neural Networks.

  18. Investigating the effect of lateral viscosity variations in the Earth's mantle

    Science.gov (United States)

    O'Farrell, K. A.; Lithgow-Bertelloni, C. R.

    2015-12-01

    Seismic tomography can be used to investigate radial viscosity variations on instantaneous flow models by predicting the global geoid and comparing with the observed geoid. This method is one of many that has been used to constrain viscosity structure in the Earth's mantle in the last few decades. Using the 3D mantle convection model, Stag-YY (e.g., Hernlund and Tackley, 2008), we are further able to explore the effect of lateral variations in viscosity in addition to the radial variations. Examining over 50 tomographic models we found notable differences by comparing a synthetically produced geoid with the observed geoid. Comparing S- and P-wave tomographic models, the S-wave models provided a better fit to the observed geoid. Using this large suite of 50 tomographic models, we have been able to constrain the radial viscosity structure of the Earth. We found that two types of viscosity profiles yielded equally good fits. A viscosity profile with a low transition zone viscosity and a lower mantle viscosity equal to the upper mantle, or a profile with a large lower mantle viscosity and a transition zone viscosity similar to the upper mantle. Using the set of radial viscosity profiles that gave the best fit to the observed geoid, we can explore a range of lateral viscosity variations and see how they affect the different types of tomographic models. Improving on previous studies of lateral viscosity variations (e.g. Ghosh, Becker and Zhong, 2010), we systematically explore a large range of tomographic models and density-velocity conversion factors. We explore which type of tomographic model (S- or P- wave) is more strongly affected by lateral viscosity variations, as well as the effect on isotropic and anisotropic models. We constrain the strength of lateral viscosity variations necessary to produce a high correlation between observed and predicted geoid anomalies. We will discuss the wavelength of flow that is most affected by the lateral viscosity variations

  19. The effect of carbohydrate and fat variation in euenergetic diets on postabsorptive free fatty acid release

    NARCIS (Netherlands)

    Bisschop, PH; Ackermans, MT; Endert, E; Ruiter, AFC; Meijer, AJ; Kuipers, F; Sauerwein, HP; Romijn, JA

    2002-01-01

    Diet composition and energy content modulate free fatty acid (FFA) release. The aim of this study was to evaluate the dose-response effects of euenergetic variations in dietary carbohydrate and fat content on postabsorptive FFA release. The rate of appearance (R-a) of palmitate was measured by infus

  20. Effect of camera temperature variations on stereo-digital image correlation measurements

    KAUST Repository

    Pan, Bing

    2015-11-25

    In laboratory and especially non-laboratory stereo-digital image correlation (stereo-DIC) applications, the extrinsic and intrinsic parameters of the cameras used in the system may change slightly due to the camera warm-up effect and possible variations in ambient temperature. Because these camera parameters are generally calibrated once prior to measurements and considered to be unaltered during the whole measurement period, the changes in these parameters unavoidably induce displacement/strain errors. In this study, the effect of temperature variations on stereo-DIC measurements is investigated experimentally. To quantify the errors associated with camera or ambient temperature changes, surface displacements and strains of a stationary optical quartz glass plate with near-zero thermal expansion were continuously measured using a regular stereo-DIC system. The results confirm that (1) temperature variations in the cameras and ambient environment have a considerable influence on the displacements and strains measured by stereo-DIC due to the slightly altered extrinsic and intrinsic camera parameters; and (2) the corresponding displacement and strain errors correlate with temperature changes. For the specific stereo-DIC configuration used in this work, the temperature-induced strain errors were estimated to be approximately 30–50 με/°C. To minimize the adverse effect of camera temperature variations on stereo-DIC measurements, two simple but effective solutions are suggested.

  1. Effect of frequency variation on electromagnetic pulse interaction with charges and plasma

    NARCIS (Netherlands)

    Khachatryan, A.G.; Goor, van F.A.; Verschuur, J.W.J.; Boller, K.-J.

    2005-01-01

    The effect of frequency variation (chirp) in an electromagnetic (EM) pulse on the pulse interaction with a charged particle and plasma is studied. Various types of chirp and pulse envelopes are considered. In vacuum, a charged particle receives a kick in the polarization direction after interaction

  2. Variations in Latino Parenting Practices and Their Effects on Child Cognitive Developmental Outcomes

    Science.gov (United States)

    De Von Figueroa-Moseley, Colmar; Ramey, Craig T.; Keltner, Bette; Lanzi, Robin G.

    2006-01-01

    This research examines variations in parenting and its effects on child cognitive outcomes across Latino subgroups from a national sampling that utilized a subset of 995 former Head Start Latino parents and children. Comparisons of the Parenting Dimension Inventory scaled scores revealed Latino subgroup differences on nurturance and consistency.…

  3. The effects of operational and environmental variations on anaerobic wastewater treatment systems: A review

    NARCIS (Netherlands)

    Leitao, R.; Haandel, van A.C.; Zeeman, G.; Lettinga, G.

    2006-01-01

    With the aim of improving knowledge about the stability and reliability of anaerobic wastewater treatment systems, several researchers have studied the effects of operational or environmental variations on the performance of such reactors. In general, anaerobic reactors are affected by changes in ex

  4. Effect of random variations in microstructure on the development of final creep failure in polycrystalline aggregates

    NARCIS (Netherlands)

    Giessen, E. van der; Tvergaard, V.

    1994-01-01

    Planar analyses of a unit cell containing many grains are used to study the effect of random variations in the microstructure on failure times in a metal subject to creep at high temperatures. The model accounts for intergranular failure by cavity nucleation and growth to coalescence, or by grain bo

  5. Effect of camera temperature variations on stereo-digital image correlation measurements.

    Science.gov (United States)

    Pan, Bing; Shi, Wentao; Lubineau, Gilles

    2015-12-01

    In laboratory and especially non-laboratory stereo-digital image correlation (stereo-DIC) applications, the extrinsic and intrinsic parameters of the cameras used in the system may change slightly due to the camera warm-up effect and possible variations in ambient temperature. Because these camera parameters are generally calibrated once prior to measurements and considered to be unaltered during the whole measurement period, the changes in these parameters unavoidably induce displacement/strain errors. In this study, the effect of temperature variations on stereo-DIC measurements is investigated experimentally. To quantify the errors associated with camera or ambient temperature changes, surface displacements and strains of a stationary optical quartz glass plate with near-zero thermal expansion were continuously measured using a regular stereo-DIC system. The results confirm that (1) temperature variations in the cameras and ambient environment have a considerable influence on the displacements and strains measured by stereo-DIC due to the slightly altered extrinsic and intrinsic camera parameters; and (2) the corresponding displacement and strain errors correlate with temperature changes. For the specific stereo-DIC configuration used in this work, the temperature-induced strain errors were estimated to be approximately 30-50 με/°C. To minimize the adverse effect of camera temperature variations on stereo-DIC measurements, two simple but effective solutions are suggested.

  6. Comparative study on curative effect of locking compression plate fixation and anatomical plate in treatment of Pilion fractures%锁定加压钢板与解剖钢板治疗胫骨Pilion骨折疗效比较

    Institute of Scientific and Technical Information of China (English)

    刘强; 王德国; 张月东; 王军; 张开刚

    2011-01-01

    [目的]总结比较锁定加压钢板(locking compression plate,LCP)与解剖钢板在胫骨Pilion骨折中的临床疗效.[方法]回顾2002年5月~2010年3月采用锁定加压钢板及解剖钢板治疗的胫骨Pilion骨折47例.LCP组25例,男20例,女5例,年龄19 ~61岁,平均37岁.按AO分型:A型13例,B型7例,C型5例.解剖钢板组22例,男19例,女3例;年龄23 ~64岁,平均39岁.按AO分型:A型11例,B型6例,C型5例.比较两组的手术时间、出血量、恢复工作时间、骨折愈合时间、踝关节功能及并发症发生率,参照Mazur标准评价踝关节功能.[结果]两组均随访10个月以上,LCP组随访10个月~4年,平均25.2个月.解剖钢板组随访10个月~5年,平均26.5个月.两组均骨折愈合,LCP组手术时间、手术切口、出血量、恢复工作时间、骨折愈合时间、踝关节功能及并发症发生总数优于解剖钢板组,差异有统计学意义(P<0.05).[结论] LCP及解剖钢板治疗胫骨远端骨折均可获得满意效果,但LCP具有创伤小、骨折愈合快、并发症少等优点,更加符合生物学固定原则,是治疗Pilion骨折的有效手段.%[Objective]To compare the clinic effect of the locking compression plate(LCP)fixation and the anatomical plate in treatment of Pilion fractures. [ Method ] The study involved 47 patients with Pilion fractures treated between May 2002 and March 2010. The LCP group included 25 patients(20 males and 5 females,age 19 to 61 years, at average age of 37 years) ,of whom there were 13 patients with type A fractures,7 with type B and 5 with type C according to the AO/ASIF classification. The anatomical plate group included 22 patients (19 males and 3 females, age 23 to 64 years, at average age of 39 years) , of whom there were 11 patients with type A fractures,6 with type B and 5 with type C according to the AO/ASIF classification. The operation time, intra-operative blood loss, recovery time, bone healing time, post

  7. Anxiolytic effects of kindling role of anatomical location of the kindling electrode in response to kindling of the right basolateral amygdala.

    Science.gov (United States)

    Adamec, Robert; Blundell, Jacqueline; Burton, Paul

    2004-10-22

    Study of effects of kindling on affect has been complicated by the fact that anxiogenic, anxiolytic or no effects may be observed following kindling of the amygdala. Factors affecting behavioral outcome include strain of rat, hemisphere kindled, amygdala nucleus kindled and location of the kindling electrodes within particular AP planes of a given nucleus. Previous work has suggested that kindling of the right basolateral amygdala (BLA) is predominantly anxiogenic. This conclusion was based on kindling of anterior or posterior parts of the BLA. The present study sought to clarify this conclusion by examining behavioral effects of right BLA kindling in a mid-range of AP planes not yet studied. A variety of measures of rodent anxiety-like behavior were examined, including behavior in the hole board, elevated plus maze, light/dark box, social interaction test and unconditioned acoustic startle. Anhedonic effects of kindling were assessed by a sucrose preference test with controls for fluid consumption and taste sensitivities. All effects were assessed shortly after kindling (1-2 days) and at a longer time interval (7-8 days). Kindling to four stage 5 seizures in the mid-right BLA altered behavior at all time points after kindling in all tests except the hole board and light/dark box tests. The effect of kindling was anxiolytic like in the plus maze, social interaction and startle tests. Kindling in mid-BLA also increased sucrose consumption. Effects on sucrose consumption are consistent with previous studies showing no depressive-like effects of amygdala kindling in rodents. It is hypothesized that the focal nature of the behavioral consequences of amygdala kindling are best understood in the context of the circuitry in which the cells stimulated are imbedded and the impact of kindling on functioning of those circuits.

  8. Anatomic Eponyms in Neuroradiology: Head and Neck.

    Science.gov (United States)

    Bunch, Paul M

    2016-10-01

    In medicine, an eponym is a word-typically referring to an anatomic structure, disease, or syndrome-that is derived from a person's name. Medical eponyms are ubiquitous and numerous. They are also at times controversial. Eponyms reflect medicine's rich and colorful history and can be useful for concisely conveying complex concepts. Familiarity with eponyms facilitates correct usage and accurate communication. In this article, 22 eponyms used to describe anatomic structures of the head and neck are discussed. For each structure, the author first provides a biographical account of the individual for whom the structure is named. An anatomic description and brief discussion of the structure's clinical relevance follow. PMID:27283070

  9. Image decomposition and staircase effect reduction based on total generalized variation

    Institute of Scientific and Technical Information of China (English)

    Jianlou Xu; Xiangchu Feng; Yan Hao; Yu Han

    2014-01-01

    Total variation (TV) is widely applied in image process-ing. The assumption of TV is that an image consists of piecewise constants, however, it suffers from the so-cal ed staircase effect. In order to reduce the staircase effect and preserve the edges when textures of image are extracted, a new image decomposition model is proposed in this paper. The proposed model is based on the to-tal generalized variation method which involves and balances the higher order of the structure. We also derive a numerical algorithm based on a primal-dual formulation that can be effectively imple-mented. Numerical experiments show that the proposed method can achieve a better trade-off between noise removal and texture extraction, while avoiding the staircase effect efficiently.

  10. Variational principles and governing equations in nano-dielectrics with the flexoelectric effect

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The flexoelectric effect is very strong and coupled with large strain gradients for nanoscale dielectrics. At the nanoscale, the electrostatic force cannot be ignored. In this paper, we have established the electric enthalpy variational principle for nanosized dielectrics with the strain gradient and the polarization gradient effect, as well as the effect of the electrostatic force. The complete governing equations, which include the effect of the electrostatic force, are derived from this variational principle, and based on the principle the generalized electrostatic stress is obtained, the generalized electrostatic stress contains the Maxwell stress corresponding to the polarization and strain, and stress related to the polarization gradient and strain gradient. This work provides the basis for the analysis and computations for the electromechanical problems in nanosized dielectric materials.

  11. Indexing Effects of Copy Number Variation on Genes Involved in Developmental Delay

    OpenAIRE

    Mohammed Uddin; Giovanna Pellecchia; Bhooma Thiruvahindrapuram; Lia D’Abate; Daniele Merico; Ada Chan; Mehdi Zarrei; Kristiina Tammimies; Susan Walker; Gazzellone, Matthew J.; Thomas Nalpathamkalam; Yuen, Ryan K.C.; Koenraad Devriendt; Géraldine Mathonnet; Emmanuelle Lemyre

    2016-01-01

    A challenge in clinical genomics is to predict whether copy number variation (CNV) affecting a gene or multiple genes will manifest as disease. Increasing recognition of gene dosage effects in neurodevelopmental disorders prompted us to develop a computational approach based on critical-exon (highly expressed in brain, highly conserved) examination for potential etiologic effects. Using a large CNV dataset, our updated analyses revealed significant (P 

  12. Peer Effects in the Classroom: Learning from Gender and Race Variation

    OpenAIRE

    Caroline Hoxby

    2000-01-01

    Peer effects are potentially important for understanding the optimal organization of schools, jobs, and neighborhoods, but finding evidence is difficult because people are selected into peer groups based, in part, on their unobservable characteristics. I identify the effects of peers whom a child encounters in the classroom using sources of variation that are credibly idiosyncratic, such as changes in the gender and racial composition of a grade in a school in adjacent years. I use specificat...

  13. Effect of thickness variation of bituminous layer in the structural responses of flexible pavements

    Directory of Open Access Journals (Sweden)

    Juliana Pavan Vidotto

    2014-05-01

    Full Text Available In this work, a sensitivity analysis was performed to investigate the effect of thickness variation of bituminous layer in the structural responses of flexible pavements and, therefore in performance. For this, it used traffic data from a weigh station located at Km 28 of the Immigrants Highway, at state of Sao Paulo, whose data collection was realized in 2008. The loads deriving from traffic were applied to the computational program ELSYM5 to obtain structural responses related to damage such as fatigue cracks and rutting. With these values, the damage factors were calculated and then the sensitivity analysis related to the thickness variation of bituminous layer was performed. Through the obtained results was concluded that the variation of thickness of bituminous layer have an influence on structural responses, and that damage factors related to fatigue cracks were more sensitive than those factors related to rutting.

  14. EFFECT OF PROCESS PARAMETER VARIATION ON ft IN CONVENTIONAL AND JUNCTIONLESS GATE-ALL-AROUND DEVICES

    Directory of Open Access Journals (Sweden)

    B. LAKSHMI

    2015-08-01

    Full Text Available In this paper we have studied the effect of process variations on unity gain cut- off frequency (ft in conventional and junctionless gate-all-around (GAA transistors using TCAD simulations. Three different geometrical parameters, channel doping, source/drain doping (for conventional GAA, wire doping (for junctionless GAA and gate electrode work function are studied for their sensitivity on ft. For conventional GAA, ft is more sensitive to gate length and source/drain doping and less sensitive to gate oxide thickness, ovality and channel doping and least sensitive to gate work function variations. For junctionless GAA, ft is more sensitive to gate length and gate work function variations and less sensitive to gate oxide thickness, ovality, wire doping. The non-quasi static (NQS delay is extracted for the most sensitive parameters. The trend of NQS delay is just the reverse trend of ft.

  15. Qualitative and numerical analyses of the effects of river inflow variations on mixing diagrams in estuaries

    Science.gov (United States)

    Cifuentes, L.A.; Schemel, L.E.; Sharp, J.H.

    1990-01-01

    The effects of river inflow variations on alkalinity/salinity distributions in San Francisco Bay and nitrate/salinity distributions in Delaware Bay are described. One-dimensional, advective-dispersion equations for salinity and the dissolved constituents are solved numerically and are used to simulate mixing in the estuaries. These simulations account for time-varying river inflow, variations in estuarine cross-sectional area, and longitudinally varying dispersion coefficients. The model simulates field observations better than models that use constant hydrodynamic coefficients and uniform estuarine geometry. Furthermore, field observations and model simulations are consistent with theoretical 'predictions' that the curvature of propery-salinity distributions depends on the relation between the estuarine residence time and the period of river concentration variation. ?? 1990.

  16. Analytical model for effect of temperature variation on PSF consistency in wavefront coding infrared imaging system

    Science.gov (United States)

    Feng, Bin; Shi, Zelin; Zhang, Chengshuo; Xu, Baoshu; Zhang, Xiaodong

    2016-05-01

    The point spread function (PSF) inconsistency caused by temperature variation leads to artifacts in decoded images of a wavefront coding infrared imaging system. Therefore, this paper proposes an analytical model for the effect of temperature variation on the PSF consistency. In the proposed model, a formula for the thermal deformation of an optical phase mask is derived. This formula indicates that a cubic optical phase mask (CPM) is still cubic after thermal deformation. A proposed equivalent cubic phase mask (E-CPM) is a virtual and room-temperature lens which characterizes the optical effect of temperature variation on the CPM. Additionally, a calculating method for PSF consistency after temperature variation is presented. Numerical simulation illustrates the validity of the proposed model and some significant conclusions are drawn. Given the form parameter, the PSF consistency achieved by a Ge-material CPM is better than the PSF consistency by a ZnSe-material CPM. The effect of the optical phase mask on PSF inconsistency is much slighter than that of the auxiliary lens group. A large form parameter of the CPM will introduce large defocus-insensitive aberrations, which improves the PSF consistency but degrades the room-temperature MTF.

  17. The Contribution of Dynamic Exploration to Virtual Anatomical Learning

    Directory of Open Access Journals (Sweden)

    Jan-Maarten Luursema

    2011-01-01

    Full Text Available Virtual Learning Environments are increasingly becoming part of the medical curriculum. In a previous study we (luursema et al., 2006 found that a combination of computer-implemented stereopsis (visual depth through seeing with both eyes and dynamic exploration (being able to continuously change one's viewpoint relative to the studied objects in real time is beneficial to anatomical learning, especially for subjects of low visuo spatial ability (the ability to form, retrieve, and manipulate mental representations of a visuo-spatial nature. A follow-up study (luursema et al., 2008 found the contribution of computer-implemented stereopsis to this effect to be small but significant. The present experiment investigated the contribution of dynamic exploration to anatomical learning by means of a virtual learning environment. Seventy participants were tested for visuo-spatial ability and were grouped in pairs matched for this ability. One individual of the pair actively manipulated a 3D reconstruction of the human abdomen; the other individual passively watched the interactions of the first individual on a separate screen. Learning was assessed by two anatomical learning tests. Dynamic exploration provided a small but significant benefit to anatomical learning.

  18. Long-term Cost-Effectiveness of Diagnostic Tests for Assessing Stable Chest Pain: Modeled Analysis of Anatomical and Functional Strategies.

    Science.gov (United States)

    Bertoldi, Eduardo G; Stella, Steffan F; Rohde, Luis E; Polanczyk, Carisi A

    2016-05-01

    Several tests exist for diagnosing coronary artery disease, with varying accuracy and cost. We sought to provide cost-effectiveness information to aid physicians and decision-makers in selecting the most appropriate testing strategy. We used the state-transitions (Markov) model from the Brazilian public health system perspective with a lifetime horizon. Diagnostic strategies were based on exercise electrocardiography (Ex-ECG), stress echocardiography (ECHO), single-photon emission computed tomography (SPECT), computed tomography coronary angiography (CTA), or stress cardiac magnetic resonance imaging (C-MRI) as the initial test. Systematic review provided input data for test accuracy and long-term prognosis. Cost data were derived from the Brazilian public health system. Diagnostic test strategy had a small but measurable impact in quality-adjusted life-years gained. Switching from Ex-ECG to CTA-based strategies improved outcomes at an incremental cost-effectiveness ratio of 3100 international dollars per quality-adjusted life-year. ECHO-based strategies resulted in cost and effectiveness almost identical to CTA, and SPECT-based strategies were dominated because of their much higher cost. Strategies based on stress C-MRI were most effective, but the incremental cost-effectiveness ratio vs CTA was higher than the proposed willingness-to-pay threshold. Invasive strategies were dominant in the high pretest probability setting. Sensitivity analysis showed that results were sensitive to costs of CTA, ECHO, and C-MRI. Coronary CT is cost-effective for the diagnosis of coronary artery disease and should be included in the Brazilian public health system. Stress ECHO has a similar performance and is an acceptable alternative for most patients, but invasive strategies should be reserved for patients at high risk. PMID:27080921

  19. Effects of temperature variations on guided waves propagating in composite structures

    Science.gov (United States)

    Shoja, Siavash; Berbyuk, Viktor; Boström, Anders

    2016-04-01

    Effects of temperature on guided waves propagating in composite materials is a well-known problem which has been investigated in many studies. The majority of the studies is focused on effects of high temperature. Understanding the effects of low temperature has major importance in composite structures and components which are operating in cold climate conditions such as e.g. wind turbines operating in cold climate regions. In this study first the effects of temperature variations on guided waves propagating in a composite plate is investigated experimentally in a cold climate chamber. The material is a common material used to manufacture rotor blades of wind turbines. The temperature range is 25°C to -25°C and effects of temperature variations on amplitude and phase shift of the received signal are investigated. In order to apply the effects of lowering the temperature on the received signal, the Baseline Signal Stretch (BSS) method is modified and used. The modification is based on decomposing the signal into symmetric and asymmetric modes and applying two different stretch factors on each of them. Finally the results obtained based on the new method is compared with the results of application of BSS with one stretch factor and experimental measurements. Comparisons show that an improvement is obtained using the BSS with the mode decomposition method at temperature variations of more than 25°C.

  20. The effects of operational and environmental variations on anaerobic wastewater treatment systems: a review

    Energy Technology Data Exchange (ETDEWEB)

    Leitao, R.C. [Embrapa Agroindustria Tropical (Brazilian Agricultural Research Corporation, Inst. of Tropical Agroindustry), Fortaleza (Brazil); Haandel, A.C. van [Federal University of Campina Grande (Brazil); Zeeman, G.; Lettinga, G. [Wageningen Univ. (Netherlands)

    2006-06-15

    With the aim of improving knowledge about the stability and reliability of anaerobic wastewater treatment systems, several researchers have studied the effects of operational or environmental variations on the performance of such reactors. In general, anaerobic reactors are affected by changes in external factors, but the severity of the effect is dependent upon the type, magnitude, duration and frequency of the imposed changes. The typical responses include a decrease in performance, accumulation of volatile fatty acids, drop in pH and alkalinity, change in biogas production and composition, and sludge washout. This review summarises the causes, types and effects of operational and environmental variation on anaerobic wastewater treatment systems. However, there still remain some unclear technical and scientific aspects that are necessary for the improvement of the stability and reliability of anaerobic processes. (author)

  1. The variation of health effects based on the scenarios considering release parameters and meteorological data

    International Nuclear Information System (INIS)

    The variation of health effects resulting from the severe accidents of the YGN 3 and 4 nuclear power plants was examined based on scenarios considering the release parameters and meteorological data. The release parameters and meteorological data considered in making basic scenarios are release height, heat content, release time, warning time, wind speed, rainfall rate, and atmospheric stability class. The seasonal scenarios were also made in order to estimate the seasonal variation of health effects by considering seasonal characteristics of Korea. According to the results, there are large differences in consequence analysis from scenario to although an equal amount of radioactive materials is released to the atmosphere. Also, there are large differences in health effects from season to season due to distinct seasonal characteristics of Korea. Therefore, it is necessary to consider seasonal characteristics in developing optimum emergency response strategies

  2. Effects of maternal characteristics and climatic variation on birth masses of Alaskan caribou

    Science.gov (United States)

    Adams, L.G.

    2005-01-01

    Understanding factors that influence birth mass of mammals provides insights to nutritional trade-offs made by females to optimize their reproduction, growth, and survival. I evaluated variation in birth mass of caribou (Rangifer tarandus) in central Alaska relative to maternal characteristics (age, body mass, cohort, and nutritional condition as influenced by winter severity) during 11 years with substantial variation in winter snowfall. Snowfall during gestation was the predominant factor explaining variation in birth masses, influencing birth mass inversely and through interactions with maternal age and lactation status. Maternal age effects were noted for females ??? 5 years old, declining in magnitude with each successive age class. Birth mass as a proportion of autumn maternal mass was inversely related to winter snowfall, even though there was no decrease in masses of adult females in late winter associated with severe winters. I found no evidence of a hypothesized intergenerational effect of lower birth masses for offspring of females born after severe winters. Caribou produce relatively small offspring but provide exceptional lactation support for those that survive. Conservative maternal investment before parturition may represent an optimal reproductive strategy given that caribou experience stochastic variation in winter severity during gestation, uncertainty of environmental conditions surrounding the birth season, and intense predation on neonates. ?? 2005 American Society of Mammalogists.

  3. Effects of Permeability Variations on CO2 Convection in Anisotropic and Heterogeneous Saline Formations

    Directory of Open Access Journals (Sweden)

    Chi-Ping Lin

    2016-02-01

    Full Text Available This study simulated the natural convection of dissolved carbon dioxide (CO2 in a small-scale heterogeneous saline formation using the state module ECO2N equation in the TOUGHREACT model. A one-way downscaling approach that involves using a series of sub-models in simulation procedures was proposed to efficiently simulate problems with high-scale discrepancies. This study evaluated the effects of different degrees of small-scale permeability variations on the vertical migration of dissolved CO2. The sequential Gaussian simulation model was used to generate unconditional random permeability fields for different natural logarithm of permeability (lnk variations (i.e., lnk variances and correlations in x and z directions. The results showed an identical transition zone of dissolved CO2 near the top boundary, where a constant CO2 gas saturation was specified. The local permeability variations can trigger fingerings and enhance the vertical convection of the dissolved CO2. The number of fingerings depends on the variations in permeability near the front interface of the dissolved CO2 (i.e., the bottom edge of the transition zone for the dissolved CO2. However, the fingering patterns and developments are constrained by the permeability variations along the fingering paths. At the same mean lnk permeability the convection fluxes increase with an increase in lnk variances. However, an increase in lateral correlations (i.e., increase in the correlation lengths in the x direction can slightly reduce the convection fluxes at the same lnk variance. The highly variable flux rates of the dissolved CO2 occur early and the variations in the flux rate decrease with time.

  4. Variation in voxel value distribution and effect of time between exposures in six CBCT units.

    Science.gov (United States)

    Spin-Neto, R; Gotfredsen, E; Wenzel, A

    2014-01-01

    The aim of this study is to assess the variation in voxel value distribution in volumetric data sets obtained by six cone beam CT (CBCT) units, and the effect of time between exposures. Six CBCT units [Cranex(®) 3D (CRAN; Soredex Oy, Tuusula, Finland), Scanora(®) 3D (SCAN; Soredex Oy), NewTom™ 5G (NEWT; QR Srl, Verona, Italy), Promax(®) Dimax 3 (Planmeca Oy, Helsinki, Finland), i-CAT (Imaging Sciences International, Hatfield, PA) and 3D Accuitomo FPD80 (Morita, Kyoto, Japan)] were tested. Two volumetric data sets of a dry human skull embedded in acrylic were acquired by each CBCT unit in two sessions on separate days. Each session consisted of 20 exposures: 10 acquired with 30 min between exposures and 10 acquired immediately one after the other. CBCT data were exported as digital imaging and communications in medicine (DICOM) files and converted to text files. The text files were re-organized to contain x-, y- and z-position and grey shade for each voxel. The files were merged to contain 1 record per voxel position, including the voxel values from the 20 exposures in a session. For each voxel, subtractions were performed between Data Set 1 and the remaining 19 data sets (1 - 2, 1 - 3, etc) in a session. Means, medians, ranges and standard deviations for grey shade variation in the subtraction data sets were calculated for each unit and session. For all CBCT units, variation in voxel values was observed throughout the 20 exposures. A "fingerprint" for the grey shade variation was observed for CRAN, SCAN and NEWT. For the other units, the variation was (apparently) randomly distributed. Large discrepancies in voxel value distribution are seen in CBCT images. This variation should be considered in studies that assess minute changes in CBCT images. PMID:24678846

  5. Variation in voxel value distribution and effect of time between exposures in six CBCT units.

    Science.gov (United States)

    Spin-Neto, R; Gotfredsen, E; Wenzel, A

    2014-01-01

    The aim of this study is to assess the variation in voxel value distribution in volumetric data sets obtained by six cone beam CT (CBCT) units, and the effect of time between exposures. Six CBCT units [Cranex(®) 3D (CRAN; Soredex Oy, Tuusula, Finland), Scanora(®) 3D (SCAN; Soredex Oy), NewTom™ 5G (NEWT; QR Srl, Verona, Italy), Promax(®) Dimax 3 (Planmeca Oy, Helsinki, Finland), i-CAT (Imaging Sciences International, Hatfield, PA) and 3D Accuitomo FPD80 (Morita, Kyoto, Japan)] were tested. Two volumetric data sets of a dry human skull embedded in acrylic were acquired by each CBCT unit in two sessions on separate days. Each session consisted of 20 exposures: 10 acquired with 30 min between exposures and 10 acquired immediately one after the other. CBCT data were exported as digital imaging and communications in medicine (DICOM) files and converted to text files. The text files were re-organized to contain x-, y- and z-position and grey shade for each voxel. The files were merged to contain 1 record per voxel position, including the voxel values from the 20 exposures in a session. For each voxel, subtractions were performed between Data Set 1 and the remaining 19 data sets (1 - 2, 1 - 3, etc) in a session. Means, medians, ranges and standard deviations for grey shade variation in the subtraction data sets were calculated for each unit and session. For all CBCT units, variation in voxel values was observed throughout the 20 exposures. A "fingerprint" for the grey shade variation was observed for CRAN, SCAN and NEWT. For the other units, the variation was (apparently) randomly distributed. Large discrepancies in voxel value distribution are seen in CBCT images. This variation should be considered in studies that assess minute changes in CBCT images.

  6. The effect of subdivision on variation at multi-allelic loci under balancing selection

    DEFF Research Database (Denmark)

    Schierup, M H; Vekemans, X; Charlesworth, D

    2000-01-01

    Simulations are used to investigate the expected pattern of variation at loci under different forms of multi-allelic balancing selection in a finite island model of a subdivided population. The objective is to evaluate the effect of restricted migration among demes on the distribution of polymorp......Simulations are used to investigate the expected pattern of variation at loci under different forms of multi-allelic balancing selection in a finite island model of a subdivided population. The objective is to evaluate the effect of restricted migration among demes on the distribution......, and to the possibility of inferring ancient population genetic events and processes. In addition, it is shown that, for sporophytic self-incompatibility systems, it is not necessarily true in a subdivided population that recessive alleles are more frequent than dominant ones. Udgivelsesdato: 2000-Aug...

  7. Variational resummation of effective potential in Φ4-theory with proper Goldstone modes

    International Nuclear Information System (INIS)

    The Hartree-Fock-Bogolyubov approximation, which is very good for electrons, cannot be applied to a Bose gas in the condensed phase since it makes Goldstone modes massive. We investigate this problem within O(N)-symmetric Φ4-Theory by performing a resummation of the renormalized two-loop effective potential in D=3 dimensions by Variational Perturbation Theory (VPT). Using both a longitudinal and a transversal mass as two independent variational parameters, we obtain a resummed effective potential which preserves the Goldstone theorem. Since it takes simultaneously Hartree-, Fock-, and Bogolyubov channels into account, VPT can be regarded as a proper generalization of the Hubbard-Stratonovich transformation to all values of N

  8. Pulse-Echo Ultrasonic Imaging Method for Eliminating Sample Thickness Variation Effects

    Science.gov (United States)

    Roth, Don J. (Inventor)

    1997-01-01

    A pulse-echo, immersion method for ultrasonic evaluation of a material which accounts for and eliminates nonlevelness in the equipment set-up and sample thickness variation effects employs a single transducer and automatic scanning and digital imaging to obtain an image of a property of the material, such as pore fraction. The nonlevelness and thickness variation effects are accounted for by pre-scan adjustments of the time window to insure that the echoes received at each scan point are gated in the center of the window. This information is input into the scan file so that, during the automatic scanning for the material evaluation, each received echo is centered in its time window. A cross-correlation function calculates the velocity at each scan point, which is then proportionalized to a color or grey scale and displayed on a video screen.

  9. The Ghent effect for whom? Mapping the variations of the Ghent effect across different trade unions in Denmark

    DEFF Research Database (Denmark)

    Høgedahl, Laust

    2014-01-01

    The presence of an unemployment insurance system based on voluntary membership in unemployment insurance funds (known as the ‘Ghent system’) and a high union density has long been known and well documented and even referred to as a special ‘Ghent effect’. However the Ghent system, especially...... to map Danish wage earners’ reasons for joining or leaving unemployment insurance funds and trade unions. The article finds that there are great variations among Danish trade unions in term of how strongly they are dependent on a Ghent effect as a recruiting mechanism. We may expect the same variations...

  10. Understanding Long-Term Variations in an Elephant Piosphere Effect to Manage Impacts

    OpenAIRE

    Marietjie Landman; David S Schoeman; Anthony J Hall-Martin; Kerley, Graham I. H.

    2012-01-01

    Surface water availability is a key driver of elephant impacts on biological diversity. Thus, understanding the spatio-temporal variations of these impacts in relation to water is critical to their management. However, elephant piosphere effects (i.e. the radial pattern of attenuating impact) are poorly described, with few long-term quantitative studies. Our understanding is further confounded by the complexity of systems with elephant (i.e. fenced, multiple water points, seasonal water avail...

  11. Effect of aging and genetic variations on decision making, fine motor and cognitive skills

    OpenAIRE

    Bogaers, Lise

    2011-01-01

    Aging is associated with a decline in cognition and motor function. Several SNPs have been linked to neural and cognitive variation in healthy adults. Moreover, it is suggested that the effects of genetic variants are enhanced with human aging. The present study investigates whether aging and genetic variants, in this case the BDNF and COMT Val/Met polymorphisms, influence executive functioning, fine hand motor control and cognitive skills. Fifty-seven healthy volunteers were genotyped fo...

  12. Genetic variation for parental effects on the propensity to gregarise in Locusta migratoria

    Directory of Open Access Journals (Sweden)

    Foucart Antoine

    2008-02-01

    Full Text Available Abstract Background Environmental parental effects can have important ecological and evolutionary consequences, yet little is known about genetic variation among populations in the plastic responses of offspring phenotypes to parental environmental conditions. This type of variation may lead to rapid phenotypic divergence among populations and facilitate speciation. With respect to density-dependent phenotypic plasticity, locust species (Orthoptera: family Acrididae, exhibit spectacular developmental and behavioural shifts in response to population density, called phase change. Given the significance of phase change in locust outbreaks and control, its triggering processes have been widely investigated. Whereas crowding within the lifetime of both offspring and parents has emerged as a primary causal factor of phase change, less is known about intraspecific genetic variation in the expression of phase change, and in particular in response to the parental environment. We conducted a laboratory experiment that explicitly controlled for the environmental effects of parental rearing density. This design enabled us to compare the parental effects on offspring expression of phase-related traits between two naturally-occurring, genetically distinct populations of Locusta migratoria that differed in their historical patterns of high population density outbreak events. Results We found that locusts from a historically outbreaking population of L. migratoria expressed parentally-inherited density-dependent phase changes to a greater degree than those from a historically non-outbreaking population. Conclusion Because locusts from both populations were raised in a common environment during our experiment, a genetically-based process must be responsible for the observed variation in the propensity to express phase change. This result emphasizes the importance of genetic factors in the expression of phase traits and calls for further investigations on density

  13. Anatomical characterisation of the cricothyroid membrane in females of childbearing age using computed tomography.

    LENUS (Irish Health Repository)

    Long, N

    2014-02-01

    In the event of failure to secure the airway by conventional means, it may be necessary to perform invasive airway access via the cricothyroid membrane. No studies have addressed anatomy of this structure in the obstetric population. We aimed to review the anatomical variation of this structure in a population of childbearing age.

  14. The wood anatomical range in Ilex (Aquifoliaceae) and its ecological and phylogenetic significance

    NARCIS (Netherlands)

    Baas, P.

    1973-01-01

    The wood anatomy of 81 species of Ilex is described in detail. The wood anatomical range encountered is presented in a generic description (p. 196). Data on ontogenetic changes in vessel member length and number of bars per perforation are given for three species. The great amount of variation in ma

  15. Strong links between genomic and anatomical diversity in both mammalian olfactory chemosensory systems.

    Science.gov (United States)

    Garrett, Eva C; Steiper, Michael E

    2014-05-22

    Mammalian olfaction comprises two chemosensory systems: the odorant-detecting main olfactory system (MOS) and the pheromone-detecting vomeronasal system (VNS). Mammals are diverse in their anatomical and genomic emphases on olfactory chemosensation, including the loss or reduction of these systems in some orders. Despite qualitative evidence linking the genomic evolution of the olfactory systems to specific functions and phenotypes, little work has quantitatively tested whether the genomic aspects of the mammalian olfactory chemosensory systems are correlated to anatomical diversity. We show that the genomic and anatomical variation in these systems is tightly linked in both the VNS and the MOS, though the signature of selection is different in each system. Specifically, the MOS appears to vary based on absolute organ and gene family size while the VNS appears to vary according to the relative proportion of functional genes and relative anatomical size and complexity. Furthermore, there is little evidence that these two systems are evolving in a linked fashion. The relationships between genomic and anatomical diversity strongly support a role for natural selection in shaping both the anatomical and genomic evolution of the olfactory chemosensory systems in mammals. PMID:24718758

  16. Modeling variation in early life mortality in the western lowland gorilla: Genetic, maternal and other effects.

    Science.gov (United States)

    Ahsan, Monica H; Blomquist, Gregory E

    2015-06-01

    Uncovering sources of variation in gorilla infant mortality informs conservation and life history research efforts. The international studbook for the western lowland gorilla provides information on a sample of captive gorillas large enough for which to analyze genetic, maternal, and various other effects on early life mortality in this critically endangered species. We assess the importance of variables such as sex, maternal parity, paternal age, and hand rearing with regard to infant survival. We also quantify the proportions of variation in mortality influenced by heritable variation and maternal effects from these pedigree and survival data using variance component estimation. Markov chain Monte Carlo simulations of generalized linear mixed models produce variance component distributions in an animal model framework that employs all pedigree information. Two models, one with a maternal identity component and one with both additive genetic and maternal identity components, estimate variance components for different age classes during the first 2 years of life. This is informative of the extent to which mortality risk factors change over time during gorilla infancy. Our results indicate that gorilla mortality is moderately heritable with the strongest genetic influence just after birth. Maternal effects are most important during the first 6 months of life. Interestingly, hand-reared infants have lower mortality for the first 6 months of life. Aside from hand rearing, we found other predictors commonly used in studies of primate infant mortality to have little influence in these gorilla data.

  17. Multi-allelic major effect genes interact with minor effect QTLs to control adaptive color pattern variation in Heliconius erato.

    Directory of Open Access Journals (Sweden)

    Riccardo Papa

    Full Text Available Recent studies indicate that relatively few genomic regions are repeatedly involved in the evolution of Heliconius butterfly wing patterns. Although this work demonstrates a number of cases where homologous loci underlie both convergent and divergent wing pattern change among different Heliconius species, it is still unclear exactly how many loci underlie pattern variation across the genus. To address this question for Heliconius erato, we created fifteen independent crosses utilizing the four most distinct color pattern races and analyzed color pattern segregation across a total of 1271 F2 and backcross offspring. Additionally, we used the most variable brood, an F2 cross between H. himera and the east Ecuadorian H. erato notabilis, to perform a quantitative genetic analysis of color pattern variation and produce a detailed map of the loci likely involved in the H. erato color pattern radiation. Using AFLP and gene based markers, we show that fewer major genes than previously envisioned control the color pattern variation in H. erato. We describe for the first time the genetic architecture of H. erato wing color pattern by assessing quantitative variation in addition to traditional linkage mapping. In particular, our data suggest three genomic intervals modulate the bulk of the observed variation in color. Furthermore, we also identify several modifier loci of moderate effect size that contribute to the quantitative wing pattern variation. Our results are consistent with the two-step model for the evolution of mimetic wing patterns in Heliconius and support a growing body of empirical data demonstrating the importance of major effect loci in adaptive change.

  18. Coefficient of Variation Can Identify the Most Important Effects of Experimental Treatments

    Directory of Open Access Journals (Sweden)

    José Carlos LORENZO

    2015-04-01

    Full Text Available Most agricultural experiments involve evaluation of multiple variables and at times it can be difficult to identify the biologically relevant effects of the experimental treatments after performing the traditional ANOVA, Tukey and t-tests.  The coefficient of variation formula could be an important tool to focus ‘Result and Discussion’ sections only on the most important changes produced by the experimental treatments. This short report is intended to exemplify the use of the coefficient of variation in three plant physiology experiments. The first one dealt with the effects of common bean plantlet exposure to high temperature under controlled conditions (levels: 28 and 40 °C.  The second experiment was related to common bean seed exposure to liquid nitrogen during five different periods of time (levels: 0, 7, 14, 21 and 28 days. The third experiment was bi-factorial: factor 1 was the ‘type of plant material’ (levels: pineapple plants genetically transformed and the untransformed control; and factor 2 was the ‘time of in vitro-plantlet hardening’ (levels: 0, 15 and 30 days.  Contents of phenolics, aldehydes, chlorophylls and proteins were determined. Percentage of seed germination, electrolyte leakage, peroxidase activity, plant height and weight were also measured. Experiments were monofactorial with two levels, monofactorial with five levels and bifactorial, respectively, with randomized design. The coefficient of variation showed that the most remarkable effects of high temperature were recorded in free phenolics and chlorophylls (a, b, total. Electrolyte leakage and chlorophyll b concentration were the most modified indicators as a result of seed exposure to liquid nitrogen.  In the third experiment, modification in the levels of malondialdehyde and other aldehydes were the most relevant changes resulting from factors interactions. A similar procedure has not been published, except for our previous publications, not focused

  19. Lateral laryngopharyngeal diverticulum: anatomical and videofluoroscopic study

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Milton Melciades Barbosa [Universidade Federal do Rio de Janeiro ICB/CCS/UFRJ, Laboratorio de Motilidade Digestiva e Imagem, S. F1-008, Departamento de Anatomia, Rio de Janeiro (Brazil); Koch, Hilton Augusto [Universidade Federal do Rio de Janeiro ICB/CCS/UFRJ, Departamento de Radiologia, Rio de Janeiro (Brazil)

    2005-07-01

    The aims were to characterize the anatomical region where the lateral laryngopharyngeal protrusion occurs and to define if this protrusion is a normal or a pathological entity. This protrusion was observed on frontal contrasted radiographs as an addition image on the upper portion of the laryngopharynx. We carried out a plane-by-plane qualitative anatomical study through macroscopic and mesoscopic surgical dissection on 12 pieces and analyzed through a videofluoroscopic method on frontal incidence the pharyngeal phase of the swallowing process of 33 patients who had a lateral laryngopharyngeal protrusion. The anatomical study allowed us to identify the morphological characteristics that configure the high portion of the piriform recess as a weak anatomical point. The videofluoroscopic study allowed us to observe the laryngopharyngeal protrusion and its relation to pharyngeal repletion of the contrast medium. All kinds of the observed protrusions could be classified as ''lateral laryngopharyngeal diverticula.'' The lateral diverticula were more frequent in older people. These lateral protrusions can be found on one or both sides, usually with a small volume, without sex or side prevalence. This formation is probably a sign of a pharyngeal transference difficulty associated with a deficient tissue resistance in the weak anatomical point of the high portion of the piriform recess. (orig.)

  20. Effects of spatial variation in cohesion over the concrete-rock interface on dam sliding stability

    Institute of Scientific and Technical Information of China (English)

    Alexandra Krounis; Fredrik Johansson; Stefan Larsson

    2015-01-01

    The limit equilibrium method (LEM) is widely used for sliding stability evaluation of concrete gravity dams. Failure is then commonly assumed to occur along the entire sliding surface simultaneously. However, the brittle behaviour of bonded concrete-rock contacts, in combination with the varying stress over the interface, implies that the failure of bonded dam-foundation interfaces occurs progressively. In addition, the spatial variation in cohesion may introduce weak spots where failure can be initiated. Nonetheless, the combined effect of brittle failure and spatial variation in cohesion on the overall shear strength of the interface has not been studied previously. In this paper, numerical analyses are used to investigate the effect of brittle failure in combination with spatial variation in cohesion that is taken into account by random fields with different correlation lengths. The study concludes that a possible exis-tence of weak spots along the interface has to be considered since it significantly reduces the overall shear strength of the interface, and implications for doing so are discussed.

  1. Single Transducer Ultrasonic Imaging Method that Eliminates the Effect of Plate Thickness Variation in the Image

    Science.gov (United States)

    Roth, Don J.

    1996-01-01

    This article describes a single transducer ultrasonic imaging method that eliminates the effect of plate thickness variation in the image. The method thus isolates ultrasonic variations due to material microstructure. The use of this method can result in significant cost savings because the ultrasonic image can be interpreted correctly without the need for machining to achieve precise thickness uniformity during nondestructive evaluations of material development. The method is based on measurement of ultrasonic velocity. Images obtained using the thickness-independent methodology are compared with conventional velocity and c-scan echo peak amplitude images for monolithic ceramic (silicon nitride), metal matrix composite and polymer matrix composite materials. It was found that the thickness-independent ultrasonic images reveal and quantify correctly areas of global microstructural (pore and fiber volume fraction) variation due to the elimination of thickness effects. The thickness-independent ultrasonic imaging method described in this article is currently being commercialized under a cooperative agreement between NASA Lewis Research Center and Sonix, Inc.

  2. Effect of current variation on the dynamics of railgun plasma armatures

    Science.gov (United States)

    Rolader, Glenn E.; Batteh, Jad H.; Powell, John D.

    1992-10-01

    The effect of current variations on the behavior of railgun plasma armatures is investigated with a one-dimensional, time-dependent model. Three typical current profiles are considered: two inductive profiles, one with a time constant of 0.5 msec and the other with a time constant of 2.0 msec, and a capacitive profile. All three calculations are for an armature in a 5 cm square-bore railgun. It is observed that current variations create oscillations in the armature length, projectile acceleration, and projectile jerk. In addition, the current profile significantly affects the axial distribution of the plasma velocity, current density, and total pressure. The significance of these transients on the design of projectiles and the interpretation of diagnostic data is discussed, and suggestions for future calculations are outlined.

  3. Intermodel variations in projected precipitation change over the North Atlantic: Sea surface temperature effect

    Science.gov (United States)

    Long, Shang-Min; Xie, Shang-Ping

    2015-05-01

    Intermodel variations in future precipitation projection in the North Atlantic are studied using 23 state-of-art models from Phase 5 of the Coupled Model Intercomparison Project. Model uncertainty in annual mean rainfall change is locally enhanced along the Gulf Stream. The moisture budget analysis reveals that much of the model uncertainty in rainfall change can be traced back to the discrepancies in surface evaporation change and transient eddy effect among models. Results of the intermodel Singular Value Decomposition (SVD) analysis show that intermodel variations in local sea surface temperature (SST) pattern exert a strong control over the spread of rainfall projection among models through the modulation of evaporation change. The first three SVD modes explain more than 60% of the intermodel variance of rainfall projection and show distinct SST patterns with mode water-induced banded structures, reduced subpolar warming due to ocean dynamical cooling, and the Gulf Stream shift, respectively.

  4. Earthquake effects in thermal neutron variations at the high-altitude station of Northern

    Science.gov (United States)

    Antonova, Valentina; Chubenko, Alexandr; Kryukov, Sergey; Lutsenko, Vadim

    2016-04-01

    Results of study of thermal neutron variations under various space and geophysical conditions on the basis of measurements on stationary installations with high statistical accuracy are presented. Installations are located close to the fault of the earth's crust at the high-altitude station of cosmic rays (3340 m above sea level, 43.02 N, 76.56 E, 20 km from Almaty) in the mountains of Northern Tien-Shan. Responses of the most effective gelio- and geophysical events (variations of atmospheric pressure, coronal mass ejections, earthquakes) has consistently considered in the variations of the thermal neutron flux and compared with variations of high-energy neutrons (standard monitor 18NM64) of galactic origin during these periods. Coefficients of correlation were calculated between data of thermal neutron detectors and data of the neutron monitor, recording the intensity of high-energy particles. High correlation coefficients and similarity of responses to changes of space and geophysical conditions are obtained, that confirms the conclusion of the genetic connection of thermal neutrons with high-energy neutrons of galactic origin and suggests same sources of disturbances in the absence of seismic activity. Observations and analysis of experimental data during the activation of seismic activity in the vicinity of Almaty showed the frequent breakdown of the correlation between the intensity of thermal and high-energy neutrons and the absence of similarity between variations during these periods. We suppose that the additional thermal neutron flux of the lithospheric origin appears under these conditions. Method of separating of thermal neutron flux variations of the lithospheric origin from neutrons variations generated in the atmosphere by subtracting the normalized data is proposed, taking into account the conclusion that variations caused with the atmospheric and interplanetary origins in thermal neutron detectors are similar to variations of high-energy neutrons

  5. Population genetic variation in the tree fern Alsophila spinulosa (Cyatheaceae: effects of reproductive strategy.

    Directory of Open Access Journals (Sweden)

    Ting Wang

    Full Text Available BACKGROUND: Essentially all ferns can perform both sexual and asexual reproduction. Their populations represent suitable study objects to test the population genetic effects of different reproductive systems. Using the diploid homosporous fern Alsophila spinulosa as an example species, the main purpose of this study was to assess the relative impact of sexual and asexual reproduction on the level and structure of population genetic variation. METHODOLOGY/PRINCIPAL FINDINGS: Inter-simple sequence repeats analysis was conducted on 140 individuals collected from seven populations (HSG, LCH, BPC, MPG, GX, LD, and ZHG in China. Seventy-four polymorphic bands discriminated a total of 127 multilocus genotypes. Character compatibility analysis revealed that 50.0 to 70.0% of the genotypes had to be deleted in order to obtain a tree-like structure in the data set from populations HSG, LCH, MPG, BPC, GX, and LD; and there was a gradual decrease of conflict in the data set when genotypes with the highest incompatibility counts were successively deleted. In contrast, in population ZHG, only 33.3% of genotypes had to be removed to achieve complete compatibility in the data set, which showed a sharp decline in incompatibility upon the deletion of those genotypes. All populations examined possessed similar levels of genetic variation. Population ZHG was not found to be more differentiated than the other populations. CONCLUSIONS/SIGNIFICANCE: Sexual recombination is the predominant source of genetic variation in most of the examined populations of A. spinulosa. However, somatic mutation contributes most to the genetic variation in population ZHG. This change of the primary mode of reproduction does not cause a significant difference in the population genetic composition. Character compatibility analysis represents an effective approach to separate the role of sexual and asexual components in shaping the genetic pattern of fern populations.

  6. Analysis of anatomic variability in children with low mathematical skills

    Science.gov (United States)

    Han, Zhaoying; Fuchs, Lynn; Davis, Nikki; Cannistraci, Christopher J.; Anderson, Adam W.; Gore, John C.; Dawant, Benoit M.

    2008-03-01

    Mathematical difficulty affects approximately 5-9% of the population. Studies on individuals with dyscalculia, a neurologically based math disorder, provide important insight into the neural correlates of mathematical ability. For example, cognitive theories, neuropsychological studies, and functional neuroimaging studies in individuals with dyscalculia suggest that the bilateral parietal lobes and intraparietal sulcus are central to mathematical performance. The purpose of the present study was to investigate morphological differences in a group of third grade children with poor math skills. We compare population averages of children with low math skill (MD) to gender and age matched controls with average math ability. Anatomical data were gathered with high resolution MRI and four different population averaging methods were used to study the effect of the normalization technique on the results. Statistical results based on the deformation fields between the two groups show anatomical differences in the bilateral parietal lobes, right frontal lobe, and left occipital/parietal lobe.

  7. Anatomic Breast Coordinate System for Mammogram Analysis

    DEFF Research Database (Denmark)

    Karemore, Gopal Raghunath; Brandt, S; Karssemeijer, N;

    2011-01-01

    inside the breast. Most of the risk assessment and CAD modules use a breast region in a image centered Cartesian x,y coordinate system. Nevertheless, anatomical structure follows curve-linear trajectories. We examined an anatomical breast coordinate system that preserves the anatomical correspondence...... between the mammograms and allows extracting not only the aligned position but also the orientation aligned with the anatomy of the breast tissue structure. Materials and Methods The coordinate system used the nipple location as the point A and the border of the pectoral muscle as a line BC. The skin air...... was represented by geodesic distance (s) from nipple and parametric angle (¿) as shown in figure 1. The scoring technique called MTR (mammographic texture resemblance marker) used this breast coordinate system to extract Gaussian derivative features. The features extracted using the (x,y) and the curve...

  8. Tissue-specific effects of genetic and epigenetic variation on gene regulation and splicing.

    Directory of Open Access Journals (Sweden)

    Maria Gutierrez-Arcelus

    2015-01-01

    Full Text Available Understanding how genetic variation affects distinct cellular phenotypes, such as gene expression levels, alternative splicing and DNA methylation levels, is essential for better understanding of complex diseases and traits. Furthermore, how inter-individual variation of DNA methylation is associated to gene expression is just starting to be studied. In this study, we use the GenCord cohort of 204 newborn Europeans' lymphoblastoid cell lines, T-cells and fibroblasts derived from umbilical cords. The samples were previously genotyped for 2.5 million SNPs, mRNA-sequenced, and assayed for methylation levels in 482,421 CpG sites. We observe that methylation sites associated to expression levels are enriched in enhancers, gene bodies and CpG island shores. We show that while the correlation between DNA methylation and gene expression can be positive or negative, it is very consistent across cell-types. However, this epigenetic association to gene expression appears more tissue-specific than the genetic effects on gene expression or DNA methylation (observed in both sharing estimations based on P-values and effect size correlations between cell-types. This predominance of genetic effects can also be reflected by the observation that allele specific expression differences between individuals dominate over tissue-specific effects. Additionally, we discover genetic effects on alternative splicing and interestingly, a large amount of DNA methylation correlating to alternative splicing, both in a tissue-specific manner. The locations of the SNPs and methylation sites involved in these associations highlight the participation of promoter proximal and distant regulatory regions on alternative splicing. Overall, our results provide high-resolution analyses showing how genome sequence variation has a broad effect on cellular phenotypes across cell-types, whereas epigenetic factors provide a secondary layer of variation that is more tissue-specific. Furthermore

  9. Standardized anatomic space for abdominal fat quantification

    Science.gov (United States)

    Tong, Yubing; Udupa, Jayaram K.; Torigian, Drew A.

    2014-03-01

    The ability to accurately measure subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) from images is important for improved assessment and management of patients with various conditions such as obesity, diabetes mellitus, obstructive sleep apnea, cardiovascular disease, kidney disease, and degenerative disease. Although imaging and analysis methods to measure the volume of these tissue components have been developed [1, 2], in clinical practice, an estimate of the amount of fat is obtained from just one transverse abdominal CT slice typically acquired at the level of the L4-L5 vertebrae for various reasons including decreased radiation exposure and cost [3-5]. It is generally assumed that such an estimate reliably depicts the burden of fat in the body. This paper sets out to answer two questions related to this issue which have not been addressed in the literature. How does one ensure that the slices used for correlation calculation from different subjects are at the same anatomic location? At what anatomic location do the volumes of SAT and VAT correlate maximally with the corresponding single-slice area measures? To answer these questions, we propose two approaches for slice localization: linear mapping and non-linear mapping which is a novel learning based strategy for mapping slice locations to a standardized anatomic space so that same anatomic slice locations are identified in different subjects. We then study the volume-to-area correlations and determine where they become maximal. We demonstrate on 50 abdominal CT data sets that this mapping achieves significantly improved consistency of anatomic localization compared to current practice. Our results also indicate that maximum correlations are achieved at different anatomic locations for SAT and VAT which are both different from the L4-L5 junction commonly utilized.

  10. Collaborative regression-based anatomical landmark detection

    Science.gov (United States)

    Gao, Yaozong; Shen, Dinggang

    2015-12-01

    Anatomical landmark detection plays an important role in medical image analysis, e.g. for registration, segmentation and quantitative analysis. Among the various existing methods for landmark detection, regression-based methods have recently attracted much attention due to their robustness and efficiency. In these methods, landmarks are localised through voting from all image voxels, which is completely different from the classification-based methods that use voxel-wise classification to detect landmarks. Despite their robustness, the accuracy of regression-based landmark detection methods is often limited due to (1) the inclusion of uninformative image voxels in the voting procedure, and (2) the lack of effective ways to incorporate inter-landmark spatial dependency into the detection step. In this paper, we propose a collaborative landmark detection framework to address these limitations. The concept of collaboration is reflected in two aspects. (1) Multi-resolution collaboration. A multi-resolution strategy is proposed to hierarchically localise landmarks by gradually excluding uninformative votes from faraway voxels. Moreover, for informative voxels near the landmark, a spherical sampling strategy is also designed at the training stage to improve their prediction accuracy. (2) Inter-landmark collaboration. A confidence-based landmark detection strategy is proposed to improve the detection accuracy of ‘difficult-to-detect’ landmarks by using spatial guidance from ‘easy-to-detect’ landmarks. To evaluate our method, we conducted experiments extensively on three datasets for detecting prostate landmarks and head & neck landmarks in computed tomography images, and also dental landmarks in cone beam computed tomography images. The results show the effectiveness of our collaborative landmark detection framework in improving landmark detection accuracy, compared to other state-of-the-art methods.

  11. Validation of Setaria (L. P. Beauv Species based on Palyonological and Anatomical Techniques.

    Directory of Open Access Journals (Sweden)

    Abdul nazir

    2014-05-01

    Full Text Available In present study external morphology, leaf epidermal anatomy and pollen structureof three species of genus Setaria(Poaceaeviz., S. glauca, S. verticillata and S. viridiswere studied. The major emphasis was on the importance of palyno-anatomical characters used as an aid in plant systematics. Light microscopy (LM and scanning electron microscopy (SEMwere used to study leaf epidermal anatomy and pollen structure.Palyno-anatomical analysis of genus Setaria shows variations within the species. It is stated that the study based on classical and modern approaches is very useful for systematic delimitation of problematic taxa like Setaria.

  12. Congenital neck masses: embryological and anatomical perspectives

    Directory of Open Access Journals (Sweden)

    Zahida Rasool

    2013-08-01

    Full Text Available Neck masses are a common problem in paediatric age group. They tend to occur frequently and pose a diagnostic dilemma to the ENT surgeons. Although the midline and lateral neck masses differ considerably in their texture and presentation but the embryological perspective of these masses is not mostly understood along with the fundamental anatomical knowledge. The article tries to correlate the embryological, anatomical and clinical perspectives for the same. [Int J Res Med Sci 2013; 1(4.000: 329-332

  13. Anatomical basis for Wilms tumor surgery

    Directory of Open Access Journals (Sweden)

    Trobs R

    2009-01-01

    Full Text Available Wilms tumor surgery requires meticulous planning and sophisticated surgical technique. Detailed anatomical knowledge can facilitate the uneventful performance of tumor nephrectomy and cannot be replaced by advanced and sophisticated imaging techniques. We can define two main goals for surgery: (1 exact staging as well as (2 safe and complete resection of tumor without spillage. This review aims to review the anatomical basis for Wilms tumor surgery. It focuses on the surgical anatomy of retroperitoneal space, aorta, vena cava and their large branches with lymphatics. Types and management of vascular injuries are discussed.

  14. The contextual interference effect for skill variations from the same and different generalized motor programs.

    Science.gov (United States)

    Sekiya, H; Magill, R A; Sidaway, B; Anderson, D I

    1994-12-01

    Magill and Hall (1990) hypothesized that the contextual interference (CI) effect is found only when task variations to be learned are governed by different generalized motor programs (GMPs). The present experiments examined their hypothesis by requiring subjects to learn variations of a tapping task that had either different (Experiment 1) or the same (Experiment 2) relative timing structure. In each experiment, subjects (N = 36) performed 270 acquisition trials with knowledge of results (KR) in either a blocked or a serial order. One day later, subjects performed 30 retention trials without KR. In data analyses, errors due to parameter modifications were dissociated from errors due to GMP construction to examine which process was responsible for the CI effect. In both experiments, parameter learning created a CI effect while GMP learning failed to produce a CI effect. In the light of these findings, a modification is proposed to the Magill and Hall (1990) hypothesis that takes into account these distinct processes in motor learning. PMID:7886282

  15. Effect of Sea Level Variation on Tidal Characteristic Values for the East China Sea

    Institute of Scientific and Technical Information of China (English)

    于宜法; 俞聿修; 左军成; 万振文; 陈宗镛

    2003-01-01

    Tidal waves in the East China Sea are simulated numerically with POM(Princeton Ocean Model) model for normal mean sea level, 30 cm higher, 60 cm higher, and 100 cm higher, respectively, and the simulated result is compared with the harmonic analysis result of hourly sea level data from 19 tide gauges for more than 19 years. It is indicated that the long-term mean sea level variation affects notably tidal waves in this region. Generally, the tidal amplitude increases when the mean sea level rises, but this relationship may be inverse for some sea areas. The maximal variation of tidal amplitude takes place in the zones near the Fujian coast and the Zhejiang coast, rather than the shallowest Bohai Sea. The maximum increase of M2 amplitude can exceed about 15 cm corresponding to the 60 cm rise of the mean sea level along the Fujian coast. The other regions with large variations of tidal amplitude are those along the Jiangsu coast, the south-east coast of Shandong, and the south-east coast of Dalian. The propagation of tidal waves is also related to mean sea level variation, and the tidal phase-lag decreases generally when the mean sea level rises. Almost all the regions where the tidal phase-lag increases with rising mean sea level are close to amphidromic points, meanwhile the spatial area of such regions is very small. Because the influence of mean sea level variation upon tidal waves is spatially marked, such spatial effect should be considered in calculation of the tidal characteristic value and engineering water level. In the region where the amplitudes of the major tidal constituents increase, the probable maximum high water level becomes higher, the probable maximum low water level becomes lower, and both design water level andcheck water level increase obviously. For example, the design water level at Xiamen increases by 13.5 cm due to the variation of tidal waves when the mean sea level rises 60 cm, the total increase of design water level being 73.5 cm.

  16. Surgical methods and clinical effects of anatomical retroperitoneal laparoscopy radical ne-phrectomy%后腹腔镜下解剖性根治性肾切除术的手术方法及临床效果

    Institute of Scientific and Technical Information of China (English)

    种庆贵; 宋爱君; 郭艳

    2014-01-01

    目的:介绍后腹腔镜下解剖性根治性肾切除术的手术方法及临床效果。方法对187例肾癌患者实施后腹腔镜下解剖性根治性肾切除术。其中左侧103例,右侧84例;肿瘤最大径2.0~8.2 cm,平均4.6 cm;所有患者均常规制备后腹腔间隙,按顺序分别进入相对无血管解剖层面进行分离,腰大肌为背侧标志,膈肌为肾上极后侧标志,肾上腺为肾上方内侧标志,腹膜为腹侧标志,下腔静脉与腹主动脉是内侧的标志,髂血管是 Gerota 筋膜锥尖部的解剖标志。结果所有手术均获成功,无中转开放手术,术中无明显并发症发生。手术时间90~150 min,平均110 min;出血60~100 ml,平均75 ml;恢复饮食和下床活动时间分别为 l.3 d 和1.2 d;术后3~7 d 出院。142例患者术后随访6~42个月,其中1例出现腹膜后淋巴结转移,余经 B 超及胸片检查未见局部复发或远处转移。结论后腹腔镜下解剖性根治性肾切除术具有解剖层次清楚,术中出血少,术野清晰,疗效确切,并发症少,恢复快等优点,为需要根治性肾切除术的患者提供了更好的选择。%Objective To introduce the technique and clinical effect of anatomical retroperitone-al laparoscopy radical nephrectomy. Methods A total of 187 patients underwent anatomical retroperito-neal laparoscopy radical nephrectomy. Among them,103 cases of tumor located in the left kidney and 84 cases located in the right kidney. The maximum diameter of tumor was 2. 0 to 8. 2 cm,with an average di-ameter of 4. 6 cm. Retroperitoneal space was created routinely at lateral decubitus position. Relatively bloodless planes were orderly entered for exposure and separation of the kidney outside Gerota’s fascia. In the first place,the greater psoas was identified as the dorsal marker. Then the diaphragmatic muscle was identified as the posterior mark of the upper pole of the kidney,and the adrenal gland as

  17. Evolving Landscapes: the Effect of Genetic Variation on Salt Marsh Erosion

    Science.gov (United States)

    Bernik, B. M.; Blum, M. J.

    2014-12-01

    Ecogeomorphic studies have demonstrated that biota can exert influence over geomorphic processes, such as sediment transport, which in turn have biotic consequences and generate complex feedbacks. However, little attention has been paid to the potential for feedback to arise from evolutionary processes as population genetic composition changes in response to changing physical landscapes. In coastal ecosystems experiencing land loss, for example, shoreline erosion entails reduced plant survival and reproduction, and thereby represents a geomorphic response with inherent consequences for evolutionary fitness. To get at this topic, we examined the effect of genetic variation in the saltmarsh grass Spartina alterniflora, a renowned ecosystem engineer, on rates of shoreline erosion. Field transplantation studies and controlled greenhouse experiments were conducted to compare different genotypes from both wild and cultivated populations. Plant traits, soil properties, accretion/subsidence, and rates of land loss were measured. We found significant differences in rates of erosion between field plots occupied by different genotypes. Differences in erosion corresponded to variation in soil properties including critical shear stress and subsidence. Plant traits that differed across genotypes included belowground biomass, root tensile strength, and C:N ratios. Our results demonstrate the importance of genetic variation to salt marsh functioning, elucidating the relationship between evolutionary processes and ecogeomorphic dynamics in these systems. Because evolutionary processes can occur on ecological timescales, the direction and strength of ecogeomorphic feedbacks may be more dynamic than previously accounted for.

  18. Load variation effects on the pressure fluctuations exerted on a Kaplan turbine runner

    International Nuclear Information System (INIS)

    Introduction of intermittent electricity production systems like wind power and solar systems to electricity market together with the consumption-based electricity production resulted in numerous start/stops, load variations and off-design operation of water turbines. The hydropower systems suffer from the varying loads exerted on the stationary and rotating parts of the turbines during load variations which they are not designed for. On the other hand, investigations on part load operation of single regulated turbines, i.e., Francis and propeller, proved the formation of rotating vortex rope (RVR) in the draft tube. The RVR induces oscillating flow both in plunging and rotating modes which results in oscillating force with two different frequencies on the runner blades, bearings and other rotating parts of the turbine. The purpose of this study is to investigate the effect of transient operations on the pressure fluctuations on the runner and mechanism of the RVR formation/mitigation. Draft tube and runner blades of the Porjus U9 model, a Kaplan turbine, were equipped with pressure sensors. The model was run in off-cam mode during different load variation conditions to check the runner performance under unsteady condition. The results showed that the transients between the best efficiency point and the high load happens in a smooth way while transitions to/from the part load, where rotating vortex rope (RVR) forms in the draft tube induces high level of fluctuations with two frequencies on the runner; plunging and rotating mode of the RVR

  19. Load variation effects on the pressure fluctuations exerted on a Kaplan turbine runner

    Science.gov (United States)

    Amiri, K.; Mulu, B.; Raisee, M.; Cervantes, M. J.

    2014-03-01

    Introduction of intermittent electricity production systems like wind power and solar systems to electricity market together with the consumption-based electricity production resulted in numerous start/stops, load variations and off-design operation of water turbines. The hydropower systems suffer from the varying loads exerted on the stationary and rotating parts of the turbines during load variations which they are not designed for. On the other hand, investigations on part load operation of single regulated turbines, i.e., Francis and propeller, proved the formation of rotating vortex rope (RVR) in the draft tube. The RVR induces oscillating flow both in plunging and rotating modes which results in oscillating force with two different frequencies on the runner blades, bearings and other rotating parts of the turbine. The purpose of this study is to investigate the effect of transient operations on the pressure fluctuations on the runner and mechanism of the RVR formation/mitigation. Draft tube and runner blades of the Porjus U9 model, a Kaplan turbine, were equipped with pressure sensors. The model was run in off-cam mode during different load variation conditions to check the runner performance under unsteady condition. The results showed that the transients between the best efficiency point and the high load happens in a smooth way while transitions to/from the part load, where rotating vortex rope (RVR) forms in the draft tube induces high level of fluctuations with two frequencies on the runner; plunging and rotating mode of the RVR.

  20. Gamma irradiation effect on the formation of Clonal variation from catharantus roseus plant

    International Nuclear Information System (INIS)

    Clonal variation have been found in Catharantus roseus plant after gamma irradiation. Several doses have been used to produce clonal variation. The most effective doses used to perform better clonal variation was 20 krad. About 103 seeds irradiated for every radiation treatment, but only several clones were grown better than wild type. We have success to get (M) seeds the expected mutant. The seeds from selected mutant are bigger when compare to the wild type and growth better on medium containing 5-methyl Tryptophan (5-MT). The chlorophyll content is higher (almost twice) as compared to the wild type. Fulther experiment continue to do in vitro culture in order to develop embryonic callus from leaf tip and leaf base. Several manipulation of auxin and cytokini have been used to differentiate the callus formation. Modified MS medium with kinetin and cytokinin (10:1) can induce globular embryo like structure. Dragendrof alkaloid reagent were used to determine high alkaloid clones from the expected mutant. TLC analysis from callus mutant shows 3 clear bands with subsequence Rf about 0.22, 0.58 while control shows two smearing bands at 0.21 and 0.52

  1. Understanding the current anatomical competence landscape: Comparing perceptions of program directors, residents, and fourth-year medical students.

    Science.gov (United States)

    Fillmore, Erin P; Brokaw, James J; Kochhar, Komal; Nalin, Peter M

    2016-07-01

    A mixed methods survey of fourth-year medical students, resident physicians, and residency program directors at the Indiana University School of Medicine gathered perceptions of anatomical competence-defined as the anatomical education necessary for effective clinical practice. The survey items explored numerous aspects of anatomical competence, including the most effective modes of instruction, perceptions of readiness for clinical practice, and specific suggestions for improving anatomical education during medical school and residency. The response rate was 46% for fourth-year medical students, 47% for residents (as graduates from 137 medical schools), and 71% for program directors. A majority of students and residents reported that their course in Gross Anatomy prepared them well for clinical practice; that cadaveric dissection was important in the early development of their anatomical competence; and that placing a greater emphasis on clinical relevance in medical school would have improved their anatomical competence even further. However, in terms of anatomical preparedness upon entering residency, the program directors rated their residents less prepared than the residents rated themselves. All three groups agreed that there is need for additional opportunities for anatomical educational during medical school and residency. Suggestions for improving anatomical education included the following: providing more opportunities for cadaveric dissection during medical school and residency; more consistent teaching of anatomy for clinical practice; more workshops that review anatomy; and better integration of anatomy with the teaching of other subjects during medical school. Anat Sci Educ 9: 307-318. © 2015 American Association of Anatomists. PMID:26632977

  2. Understanding the current anatomical competence landscape: Comparing perceptions of program directors, residents, and fourth-year medical students.

    Science.gov (United States)

    Fillmore, Erin P; Brokaw, James J; Kochhar, Komal; Nalin, Peter M

    2016-07-01

    A mixed methods survey of fourth-year medical students, resident physicians, and residency program directors at the Indiana University School of Medicine gathered perceptions of anatomical competence-defined as the anatomical education necessary for effective clinical practice. The survey items explored numerous aspects of anatomical competence, including the most effective modes of instruction, perceptions of readiness for clinical practice, and specific suggestions for improving anatomical education during medical school and residency. The response rate was 46% for fourth-year medical students, 47% for residents (as graduates from 137 medical schools), and 71% for program directors. A majority of students and residents reported that their course in Gross Anatomy prepared them well for clinical practice; that cadaveric dissection was important in the early development of their anatomical competence; and that placing a greater emphasis on clinical relevance in medical school would have improved their anatomical competence even further. However, in terms of anatomical preparedness upon entering residency, the program directors rated their residents less prepared than the residents rated themselves. All three groups agreed that there is need for additional opportunities for anatomical educational during medical school and residency. Suggestions for improving anatomical education included the following: providing more opportunities for cadaveric dissection during medical school and residency; more consistent teaching of anatomy for clinical practice; more workshops that review anatomy; and better integration of anatomy with the teaching of other subjects during medical school. Anat Sci Educ 9: 307-318. © 2015 American Association of Anatomists.

  3. Effect of static and dynamic stretching on the diurnal variations of jump performance in soccer players.

    Directory of Open Access Journals (Sweden)

    Hamdi Chtourou

    Full Text Available PURPOSE: The present study addressed the lack of data on the effect of different types of stretching on diurnal variations in vertical jump height - i.e., squat-jump (SJ and countermovement-jump (CMJ. We hypothesized that dynamic stretching could affect the diurnal variations of jump height by producing a greater increase in short-term maximal performance in the morning than the evening through increasing core temperature at this time-of-day. METHODS: Twenty male soccer players (age, 18.6±1.3 yrs; height, 174.6±3.8 cm; body-mass, 71.1±8.6 kg; mean ± SD completed the SJ and CMJ tests either after static stretching, dynamic stretching or no-stretching protocols at two times of day, 07:00 h and 17:00 h, with a minimum of 48 hours between testing sessions. One minute after warming-up for 5 minutes by light jogging and performing one of the three stretching protocols (i.e., static stretching, dynamic stretching or no-stretching for 8 minutes, each subject completed the SJ and CMJ tests. Jumping heights were recorded and analyzed using a two-way analysis of variance with repeated measures (3 [stretching]×2 [time-of-day]. RESULTS: The SJ and CMJ heights were significantly higher at 17:00 than 07:00 h (p<0.01 after the no-stretching protocol. These daily variations disappeared (i.e., the diurnal gain decreased from 4.2±2.81% (p<0.01 to 1.81±4.39% (not-significant for SJ and from 3.99±3.43% (p<0.01 to 1.51±3.83% (not-significant for CMJ after dynamic stretching due to greater increases in SJ and CMJ heights in the morning than the evening (8.4±6.36% vs. 4.4±2.64%, p<0.05 for SJ and 10.61±5.49% vs. 6.03±3.14%, p<0.05 for CMJ. However, no significant effect of static stretching on the diurnal variations of SJ and CMJ heights was observed. CONCLUSION: Dynamic stretching affects the typical diurnal variations of SJ and CMJ and helps to counteract the lower morning values in vertical jump height.

  4. Effects of the observed J2 variations on the Earth's precession and nutation

    Science.gov (United States)

    Ferrándiz, José M.; Baenas, Tomás; Belda, Santiago

    2016-04-01

    The Earth's oblateness parameter J2 is closely related to the dynamical ellipticity H, which factorizes the main components of the precession and the different nutation terms. In most theoretical approaches to the Earth's rotation, with IAU2000 nutation theory among them, H is assumed to be constant. The precession model IAU2006 supposes H to have a conventional linear variation, based on the J2 time series derived mainly from satellite laser ranging (SLR) data for decades, which gives rise to an additional quadratic term of the precession in longitude and some corrections of the nutation terms. The time evolution of J2 is, however, too complex to be well approximated by a simple linear model. The effect of more general models including periodic terms and closer to the observed time series, although still unable to reproduce a significant part of the signal, has been seldom investigated. In this work we address the problem of deriving the effect of the observed J2 variations without resorting to such simplified models. The Hamiltonian approach to the Earth rotation is extended to allow the McCullagh's term of the potential to depend on a time-varying oblateness. An analytical solution is derived by means of a suitable perturbation method in the case of the time series provided by the Center for Space Research (CSR) of the University of Texas, which results in non-negligible contributions to the precession-nutation angles. The presentation focuses on the main effects on the longitude of the equator; a noticeable non-linear trend is superimposed to the linear main precession term, along with some periodic and decadal variations.

  5. Geographic variation and effect of area-level poverty rate on colorectal cancer screening

    Directory of Open Access Journals (Sweden)

    Schootman Mario

    2008-10-01

    Full Text Available Abstract Background With a secular trend of increasing colorectal cancer (CRC screening, concerns about disparities in CRC screening also have been rising. It is unclear if CRC screening varies geographically, if area-level poverty rate affects CRC screening, and if individual-level characteristics mediate the area-level effects on CRC screening. Methods Using 2006 Missouri Behavioral Risk Factor Surveillance System (BRFSS data, a multilevel study was conducted to examine geographic variation and the effect of area-level poverty rate on CRC screening use among persons age 50 or older. Individuals were nested within ZIP codes (ZIP5 areas, which in turn, were nested within aggregations of ZIP codes (ZIP3 areas. Six groups of individual-level covariates were considered as potential mediators. Results An estimated 51.8% of Missourians aged 50 or older adhered to CRC screening recommendations. Nearly 15% of the total variation in CRC screening lay between ZIP5 areas. Persons residing in ZIP5 areas with ≥ 10% of poverty rate had lower odds of CRC screening use than those residing in ZIP5 areas with Conclusion Large geographic variation of CRC screening exists in Missouri. Area-level poverty rate, independent of individual-level characteristics, is a significant predictor of CRC screening, but it only explains a small portion of the geographic heterogeneity of CRC screening. Individual-level factors we examined do not mediate the effect of the area-level poverty rate on CRC screening. Future studies should identify other area- and individual-level characteristics associated with CRC screening in Missouri.

  6. Detection of copy number variations and their effects in Chinese bulls

    KAUST Repository

    Zhang, Liangzhi

    2014-06-17

    Background: Copy number variations (CNVs) are a main source of genomic structural variations underlying animal evolution and production traits. Here, with one pure-blooded Angus bull as reference, we describe a genome-wide analysis of CNVs based on comparative genomic hybridization arrays in 29 Chinese domesticated bulls and examined their effects on gene expression and cattle growth traits.Results: We identified 486 copy number variable regions (CNVRs), covering 2.45% of the bovine genome, in 24 taurine (Bos taurus), together with 161 ones in 2 yaks (Bos grunniens) and 163 ones in 3 buffaloes (Bubalus bubalis). Totally, we discovered 605 integrated CNVRs, with more " loss" events than both " gain" and " both" ones, and clearly clustered them into three cattle groups. Interestingly, we confirmed their uneven distributions across chromosomes, and the differences of mitochondrion DNA copy number (gain: taurine, loss: yak & buffalo). Furthermore, we confirmed approximately 41.8% (253/605) and 70.6% (427/605) CNVRs span cattle genes and quantitative trait loci (QTLs), respectively. Finally, we confirmed 6 CNVRs in 9 chosen ones by using quantitative PCR, and further demonstrated that CNVR22 had significantly negative effects on expression of PLA2G2D gene, and both CNVR22 and CNVR310 were associated with body measurements in Chinese cattle, suggesting their key effects on gene expression and cattle traits.Conclusions: The results advanced our understanding of CNV as an important genomic structural variation in taurine, yak and buffalo. This study provides a highly valuable resource for Chinese cattle\\'s evolution and breeding researches. 2014 Zhang et al.; licensee BioMed Central Ltd.

  7. Effect of Sea Level Variation on Calculation of Design Water Level

    Institute of Scientific and Technical Information of China (English)

    左军成; 于宜法; 鲍献文; 刘德辅

    2001-01-01

    The long-term variation and seasonal variation of sea level have a notable effect on the calculation of engineering water level. Such an effect is first analyzed in this paper. The maximal amplitude of inter-annual anomaly of monthly mean sea level along the China coast is larger than 60 cm. Both the storm surge disaster and cold wave disaster are sea sonal disasters in various regions, so the water level corresponding to the 1% of the cumulative frequency in the cumulative frequency curve of hourly water level data for different seasons in various sea areas is different from design water level, for example, the difference between them reaches maximum in June, July and August for northern sea area, and maxi.mum in September, October and November for Southern China Sea. The hourly water level data of 19 gauge stations along the China coast are analyzed. Firstly, the annual mean sea level for every station is obtained; secondly, linear chan ging rates of annual mean sea level are obtained with the stochastic dynamic method; thirdly, the astronomical tide and storm surge tide are obtained by subtracting the linear fitting part from the original hourly data, finally, two distributions corresponding to the astronomical tide and wind tide are obtained according to whether the astronomical tide and storm tide are correlative or not. So the two check water levels are obtained with the joint probability method. The maximal difference between the two water levels of 100 years' recurrence is more than 30 cm. Both of the two check water levels have disadvantages in the use of observation data, so the mean value is suggested to be taken as the final check water level. A comparison between the two check water levels indicates that the effect of sea level variation upon design water level and check water level is larger than 80 cm at some stations.

  8. Implementation of a variational approach to approximate particle number projection with effective forces

    CERN Document Server

    Valor, A; Robledo, L M

    2000-01-01

    Kamlah's second-order method for approximate particle number projection is applied for the first time to variational calculations with effective forces. High spin states of normal and superdeformed nuclei have been calculated with the finite range density dependent Gogny force for several nuclei. Advantages and drawbacks of the Kamlah second-order method as compared to the Lipkin-Nogami recipe are thoroughly discussed. We find that the Lipkin-Nogami prescription occasionally may fail to find the right energy minimum in the strong pairing regime and that Kamlah's second-order approach though providing better results than the LN one may break down in some limiting situations.

  9. A variational approach to approximate particle number projection with effective forces

    CERN Document Server

    Valor, A; Robledo, L M

    1999-01-01

    Kamlah's second order method for approximate particle number projection is applied for the first time to variational calculations with effective forces. High spin states of normal and superdeformed nuclei have been calculated with the finite range density dependent Gogny force for several nuclei. Advantages and drawbacks of the Kamlah second order method as compared to the Lipkin-Nogami recipe are thoroughly discussed. We find that the Lipkin-Nogami prescription occasionally may fail to find the right energy minimum in the strong pairing regime and that Kamlah's second order approach, though providing better results than the LN one, may break down in some limiting situations.

  10. Effect of adiabatic variation of dust charges on dust acoustic solitary waves in magnetized dusty plasmas

    Institute of Scientific and Technical Information of China (English)

    Duan Wen-Shan

    2004-01-01

    The effect of dust charging and the influence of its adiabatic variation on dust acoustic waves is investigated. By employing the reductive perturbation technique we derived a Zakharov-Kuznetsov (ZK) equation for small amplitude dust acoustic waves. We have analytically verified that there are only rarefactive solitary waves for this system. The instability region for one-dimensional solitary wave under transverse perturbations has also been obtained. The obliquely propagating solitary waves to the z-direction for the ZK equation are given in this paper as well.

  11. The story turned upside down: Meaning effects linked to variations on narrative structure

    DEFF Research Database (Denmark)

    Bundgaard, Peer; Østergaard, Svend

    2007-01-01

    This text has two parts. In the first section we intend to define the narrative schema—the canonical plot structure—as a symbolic form in Ernst Cassirer’s sense of the term. This basically implies that the narrative schema is not an invariant higher order combinatorial form, but may itself...... be subject to variations in view of yielding specific meaning effects. This is because the production and reception of a narrative is a dynamic process where physical forces, modal forces and intentions set up a space of possibilities for the narrative trajectory. We therefore propose a determination...

  12. Effects of Velocity-Slip and Viscosity Variation in Squeeze Film Lubrication of Two Circular Plates

    Directory of Open Access Journals (Sweden)

    R.R. Rao

    2013-03-01

    Full Text Available A generalized form of Reynolds equation for two symmetrical surfaces is taken by considering velocity-slip at the bearing surfaces. This equation is applied to study the effects of velocity-slip and viscosity variation for the lubrication of squeeze films between two circular plates. Expressions for the load capacity and squeezing time obtained are also studied theoretically for various parameters. The load capacity and squeezing time decreases due to slip. They increase due to the presence of high viscous layer near the surface and decrease due to low viscous layer.

  13. Seasonal variations and aeration effects on water quality improvements and physiological responses of Nymphaea tetragona Georgi.

    Science.gov (United States)

    Lu, Xiao-Ming; Lu, Peng-Zhen; Huang, Min-Sheng; Dai, Ling-Peng

    2013-01-01

    Seasonal variations and aeration effects on water quality improvements and the physiological responses of Nymphaea tetragona Georgi were investigated with mesocosm experiments. Plants were hydroponically cultivated in six purifying tanks (aerated, non-aerated) and the characteristics of the plants were measured. Water quality improvements in purifying tanks were evaluated by comparing to the control tanks. The results showed that continuous aeration affected the plant morphology and physiology. The lengths of the roots, petioles and leaf limbs in aeration conditions were shorter than in non-aeration conditions. Chlorophyll and soluble protein contents of the leaf limbs in aerated tanks decreased, while peroxidase and catalase activities of roots tissues increased. In spring and summer, effects of aeration on the plants were less than in autumn. Total nitrogen (TN) and ammonia nitrogen (NH4(+)-N) in aerated tanks were lower than in non-aerated tanks, while total phosphorus (TP) and dissolved phosphorus (DP) increased in spring and summer. In autumn, effects of aeration on the plants became more significant. TN, NH4(+)-N, TP and DP became higher in aerated tanks than in non-aerated tanks in autumn. This work provided evidences for regulating aeration techniques based on seasonal variations of the plant physiology in restoring polluted stagnant water.

  14. Variações do sistema arterial hepático e sua aplicabilidade na bipartição do fígado: estudo anatômico em cadáveres Hepatic artery system variations correlated to split-liver surgery: anatomic study in cadavers

    Directory of Open Access Journals (Sweden)

    Pedro Luiz BERTEVELLO

    2002-04-01

    .Background - The liver donor shortage and the higher demand on liver transplantation led to advanced liver surgery techniques in order to better utilization of the cadaveric liver donors. That is why the split-liver technique had been applicated in liver transplantation where the liver after been divided into two lobes would be implanted in two recipients. Aims - This paper has the goal of study both the extra-hepatic arterial distribuition and anatomie of the liver with application on the split-liver transplantation separating the liver in right and left hepatic lobe. Patients and Methods - The authors studied 60 livers from fresh cadaver looking at hepatic artery and its main anatomic variations correlating with split-liver surgery. The liver was split into two portions, right and left lobe. Results - The total liver weight was 1536 ± 361,8 g, right hepatic lobe 890,3 ± 230,9 g and left hepatic lobe 649,3 ± 172,6 g. Common hepatic trunk was found in one (1,6% case and came from superior mesenteric artery and in another one (1,6%, both left hepatic artery and left gastric artery came from the abdominal aorta. The right hepatic artery raised from celiac trunk in 44 (73,3% cases, and in 15 (25% from superior mesenteric artery it was acessory in 11 (18,3% cases and dominant in 4 (6,6%. The left hepatic artery was acessory of left gastric artery in 2 (3,3% cases. Hepatic artery trifurcation was found in 9 (15% cases out of this 6 (10% to segment IV, 2 (3,3% to segment III and 1 (1,6% to segment II. Also we found 2 (3,3% medium hepatic artery to segment IV. Conclusion - Hepatic artery variations allowed liver section into right and left hepatic lobe.

  15. Handbook of anatomical models for radiation dosimetry

    CERN Document Server

    Eckerman, Keith F

    2010-01-01

    Covering the history of human model development, this title presents the major anatomical and physical models that have been developed for human body radiation protection, diagnostic imaging, and nuclear medicine therapy. It explores how these models have evolved and the role that modern technologies have played in this development.

  16. Anatomically Plausible Surface Alignment and Reconstruction

    DEFF Research Database (Denmark)

    Paulsen, Rasmus R.; Larsen, Rasmus

    2010-01-01

    With the increasing clinical use of 3D surface scanners, there is a need for accurate and reliable algorithms that can produce anatomically plausible surfaces. In this paper, a combined method for surface alignment and reconstruction is proposed. It is based on an implicit surface representation...

  17. Influences on anatomical knowledge: The complete arguments

    NARCIS (Netherlands)

    Bergman, E.M.; Verheijen, I.W.; Scherpbier, A.J.J.A.; Vleuten, C.P.M. van der; Bruin, A.B. De

    2014-01-01

    Eight factors are claimed to have a negative influence on anatomical knowledge of medical students: (1) teaching by nonmedically qualified teachers, (2) the absence of a core anatomy curriculum, (3) decreased use of dissection as a teaching tool, (4) lack of teaching anatomy in context, (5) integrat

  18. Report of a rare anatomic variant

    DEFF Research Database (Denmark)

    De Brucker, Y; Ilsen, B; Muylaert, C;

    2015-01-01

    We report the CT findings in a case of partial anomalous pulmonary venous return (PAPVR) from the left upper lobe in an adult. PAPVR is an anatomic variant in which one to three pulmonary veins drain into the right atrium or its tributaries, rather than into the left atrium. This results in a lef...

  19. An anatomical and functional model of the human tracheobronchial tree.

    Science.gov (United States)

    Florens, M; Sapoval, B; Filoche, M

    2011-03-01

    The human tracheobronchial tree is a complex branched distribution system in charge of renewing the air inside the acini, which are the gas exchange units. We present here a systematic geometrical model of this system described as a self-similar assembly of rigid pipes. It includes the specific geometry of the upper bronchial tree and a self-similar intermediary tree with a systematic branching asymmetry. It ends by the terminal bronchioles whose generations range from 8 to 22. Unlike classical models, it does not rely on a simple scaling law. With a limited number of parameters, this model reproduces the morphometric data from various sources (Horsfield K, Dart G, Olson DE, Filley GF, Cumming G. J Appl Physiol 31: 207-217, 1971; Weibel ER. Morphometry of the Human Lung. New York: Academic Press, 1963) and the main characteristics of the ventilation. Studying various types of random variations of the airway sizes, we show that strong correlations are needed to reproduce the measured distributions. Moreover, the ventilation performances are observed to be robust against anatomical variability. The same methodology applied to the rat also permits building a geometrical model that reproduces the anatomical and ventilation characteristics of this animal. This simple model can be directly used as a common description of the entire tree in analytical or numerical studies such as the computation of air flow distribution or aerosol transport. PMID:21183626

  20. Variation in the fitness effects of mutations with population density and size in Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Huansheng Cao

    Full Text Available The fitness effects of mutations are context specific and depend on both external (e.g., environment and internal (e.g., cellular stress, genetic background factors. The influence of population size and density on fitness effects are unknown, despite the central role population size plays in the supply and fixation of mutations. We addressed this issue by comparing the fitness of 92 Keio strains (Escherichia coli K12 single gene knockouts at comparatively high (1.2×10(7 CFUs/mL and low (2.5×10(2 CFUs/mL densities, which also differed in population size (high: 1.2×10(8; low: 1.25×10(3. Twenty-eight gene deletions (30% exhibited a fitness difference, ranging from 5 to 174% (median: 35%, between the high and low densities. Our analyses suggest this variation among gene deletions in fitness responses reflected in part both gene orientation and function, of the gene properties we examined (genomic position, length, orientation, and function. Although we could not determine the relative effects of population density and size, our results suggest fitness effects of mutations vary with these two factors, and this variation is gene-specific. Besides being a mechanism for density-dependent selection (r-K selection, the dependence of fitness effects on population density and size has implications for any population that varies in size over time, including populations undergoing evolutionary rescue, species invasions into novel habitats, and cancer progression and metastasis. Further, combined with recent advances in understanding the roles of other context-specific factors in the fitness effects of mutations, our results will help address theoretical and applied biological questions more realistically.

  1. Effect of patient variation on standard- and hypo-fractionated radiotherapy of prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Xiong, W; Li, J; Ma, C-M [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA 19111 (United States)

    2005-04-07

    Recent publications suggested that the {alpha}/{beta} ratio in the well-known linear quadratic (LQ) model could be as low as 1.5 Gy for prostate cancer, indicating that prostate cancer control might be very sensitive to changes in the dose fractionation scheme. This also suggests that the standard-fractionation scheme based on large {alpha}/{beta} ratios may not be optimal for the radio-therapeutic management of prostate cancer. Hypo-fractionated radiotherapy for prostate cancer has received more attention recently as an alternative treatment strategy, which may lead to reduced treatment time and cost. However, hypo-fractionated radiotherapy may be more sensitive to patient variation in terms of disease control than standard-fractionated radiotherapy. The variation of LQ parameters {alpha} and {beta} for a patient population may compromise the outcome of the treatment. This effect can be studied by the introduction of the {sigma}{sub {alpha}} and {sigma}{sub {beta}} parameters, which are the standard deviations of Gaussian distributions around {alpha}{sub 0} and {beta}{sub 0}. The purpose of this study is to examine the effect of patient variation in {alpha} and {beta} on tumour control probability for standard- and hypo-fractionated radiotherapy of prostate cancer. The tumour control probability based on the LQ model is calculated using parameters {alpha}, {beta}, {sigma}{sub {alpha}} and {sigma}{sub {beta}}. Our results show that {sigma}{sub {alpha}} is an important parameter for radiotherapy fractionation, independent of the {alpha}/{beta} ratio. A large {sigma}{sub {alpha}} will result in a significant increase in the radiation dose required to achieve the same 95% TCP. Compared with the standard-fractionated scheme, {sigma}{sub {alpha}} has a smaller effect on hypo-fractionated treatment at lower {alpha}/{beta} ratios. On the other hand, for lower {alpha}/{beta} ratios, the {beta} term also plays a more important role in cell-killing and therefore the patient

  2. The Effect of Microstructural Variation on the Hydrogen Environment-Assisted Cracking of Monel K-500

    Science.gov (United States)

    Harris, Zachary D.; Dolph, Justin D.; Pioszak, Greger L.; Rincon Troconis, Brendy C.; Scully, John R.; Burns, James T.

    2016-07-01

    The influence of microstructural variation on hydrogen environment-assisted cracking (HEAC) of Monel K-500 was evaluated using five nominally peak-aged lots of material tested under slow-rising stress intensity loading while immersed in NaCl solution under cathodic polarizations. Minimal variation in HEAC resistance among material lots was observed for an applied potential of -950 mVSCE ( E app, vs saturated calomel), whereas lot-to-lot variability in the fracture morphology demonstrates a significant difference in the HEAC resistance at the less negative potential of -850 mVSCE, suggesting that relatively severe H environments produce sufficient crack-tip H to minimize the impact of metallurgical differences. Sensitivity analyses accomplished by varying the inputs used in decohesion-based, micromechanical models imply significant variations in HEAC resistance are possible for realistic changes in grain boundary toughness, hydrogen uptake behavior, and yield strength. Grain size, impurity segregation (including the effects of gettering elements), grain boundary character/connectivity, and crack path tortuosity are also considered in the context of HEAC susceptibility. Yield strength, global hydrogen content, as well as impurity segregation to grain boundaries, especially boron and sulfur, are speculatively considered to be the dominant contributions in determining HEAC resistance. Modifications that would incorporate the effects of grain boundary segregation are proposed for the K TH model; detailed validation of such changes require high-fidelity and quantitative inputs for the degree of grain boundary segregation. Regardless, fracture mechanics-based HEAC results, detailed microstructural characterization, and micromechanical modeling were successfully coupled to gain insights into the influences governing the microstructure-dependent HEAC susceptibility of Monel K-500.

  3. Enhanced effect of quark mass variation in Th229 and limits from Oklo data

    Science.gov (United States)

    Flambaum, V. V.; Wiringa, R. B.

    2009-03-01

    The effects of the variation of the dimensionless strong interaction parameter Xq=mq/ΛQCD (mq is the quark mass, ΛQCD is the QCD scale) are enhanced about 1.5×105 times in the 7.6 eV “nuclear clock” transition between the ground and first excited states in the Th229 nucleus and about 1×108 times in the relative shift of the 0.1 eV compound resonance in Sm150. The best terrestrial limit on the temporal variation of the fundamental constants, |δXq/Xq|Oklo natural nuclear reactor data. The results for Th229 and Sm150 are obtained by extrapolation from light nuclei where the many-body calculations can be performed more accurately. The errors produced by such extrapolation may be smaller than the errors of direct calculations in heavy nuclei. The extrapolation results are compared with the “direct” estimates obtained using the Walecka model. A number of numerical relations needed for the calculations of the variation effects in nuclear physics and atomic spectroscopy have been obtained: for the nuclear binding energy δE/E≈-1.45δmq/mq, for the spin-orbit intervals δEso/Eso≈-0.22δmq/mq, for the nuclear radius δr/r≈0.3δmq/mq (in units of ΛQCD); for the shifts of nuclear resonances and weakly bound energy levels δEr≈10δXq/Xq MeV.

  4. A literature review of the variation of dispersant effectiveness and salinity

    Energy Technology Data Exchange (ETDEWEB)

    Fingas, M. [Environment Canada, Ottawa, ON (Canada). Emergencies Science Div; Ka' aihue, L. [Prince William Regional Citizen' s Advisory Council, Anchorage, AK (United States)

    2005-07-01

    Surfactants have varying solubilities in water and varying actions toward oil and water. This paper presents a summary of the effects of water salinity on chemical dispersion. Literature reveals that effectiveness testing with salinity variations shows a consistent decrease in effectiveness at lower salinities and a decrease after a maximum salinity is reached between 20 to 40 units of salinity. In waters with 0 salinity, conventional and currently available dispersants have a very low effectiveness or are sometimes even completely ineffective, a fact which is consistent in surfactant literature. Dispersant effectiveness peaks in waters with a salinity ranging from 20 to 40. Corexit 9500 appears to be less sensitive to salinity, but still peaks at about 35. There is a relatively smooth gradient of effectiveness with salinity both as the salinity rises to a peak point of effectiveness and after it exceeds this value. The curves for this salinity effect appear to be Gaussian. While there is some evidence for a temperature-salinity interaction as noted in the data, there is not enough data to make solid conclusions. Recent data is almost exclusively measured using Corexit 9527 and Corexit 9500. Since these have the same surfactant packages, there is a concern that the results may be more relevant to these formulations than to all possible formulations. Observations on 2 field trials in freshwater appear to indicate that the laboratory tests were correct in concluding very low dispersant effectiveness in freshwater. There were few studies on the biological effects of varying salinity and given oil exposure. It was concluded that the findings in the dispersant literature reviewed here are in agreement with those in the theoretical and basic surfactant literature. The effect of ionic strength and salinity on both hydrophilic-lipophilic balance and stability is the reason for the decreased effectiveness noted at low salinities and the same decrease at high salinities

  5. Effects of Plant Growth Substances on Leaf and Stem Anatomical Structure in Glycine max (Linn.) Merr.%三种植物生长物质对大豆叶茎解剖结构的影响

    Institute of Scientific and Technical Information of China (English)

    冯乃杰; 郑殿峰; 刘冰; 张玉先; 杜吉到; 梁喜龙

    2009-01-01

    In the field cultivation condition, leaves of a soybean (Glycine max) cultivar 'Kennong 4' were treated with plant growth substances including 2-diethylaminoethyl hexanoate (DTA), choline chloride (CC) and superoxide dismutase mimics (SOD_M) at the beginning of flowering stage. Effects of 3 plant growth substances on leaf and stem anatomical structures in soybean were compared. The results showed that palisade tissues were thicker and the thickness ratio of palisade tissue to spongy tissue increased after 30 d with the treatments of 3 plant growth substances. Cross-sectional area of the main vein vascular bundle and the number of xylem vessel increased in leaves treated with SOD_M and DTA. There were no obvious effects of CC on cross-sectional area of the main vein vascular bundle and the number of xylem vessel. The 3 plant growth substances increased the thickness of petiole epidermal cell, cross-sectional area of petiole vascular bundle, number of vessels, the thickness of parenchyma, xylem, phloem in stems, and the diameter of stem.%在大田栽培条件下,大豆'垦农4号'于开花始期叶面喷施植物生长物质2-N,N-二乙氨基乙基己酸酯(DTA)、氯化胆碱(CC)和SOD模拟物(SOD_M),并比较不同植物生长物质影响大豆叶片、叶柄和茎的解剖结构.结果表明,喷施植物生长物质后30 d,叶中栅栏组织厚度及栅海比均增加;喷施SOD_M、DTA的叶中主脉维管束横截面积和木质部导管数目增加,CC对主脉维管束横截面积和木质部导管数目的影响不明显;喷施3种植物生长物质的叶柄表皮细胞厚度、叶柄维管束横截面积和导管数量增加,茎部薄壁组织、韧皮部和木质部厚度增加,茎的直径也增加.

  6. Efficient and Effective Total Variation Image Super-Resolution: A Preconditioned Operator Splitting Approach

    Directory of Open Access Journals (Sweden)

    Li-Li Huang

    2011-01-01

    Full Text Available Super-resolution is a fusion process for reconstructing a high-resolution image from a set of low-resolution images. This paper proposes a novel approach to image super-resolution based on total variation (TV regularization. We applied the Douglas-Rachford splitting technique to the constrained TV-based variational SR model which is separated into three subproblems that are easy to solve. Then, we derive an efficient and effective iterative scheme, which includes a fast iterative shrinkage/thresholding algorithm for denoising problem, a very simple noniterative algorithm for fusion part, and linear equation systems for deblurring process. Moreover, to speed up convergence, we provide an accelerated scheme based on precondition design of initial guess and forward-backward splitting technique which yields linear systems of equations with a nice structure. The proposed algorithm shares a remarkable simplicity together with a proven global rate of convergence which is significantly better than currently known lagged diffusivity fixed point iteration algorithm and fast decoupling algorithm by exploiting the alternating minimizing approach. Experimental results are presented to illustrate the effectiveness of the proposed algorithm.

  7. Effect of litter size on the variation in birth and weaning weights of Landrace piglets

    Directory of Open Access Journals (Sweden)

    Camila Duarte Prazeres

    2016-03-01

    Full Text Available The objective of this study was to evaluate the effect of the size class of the litter at birth on the variation in birth and weaning weights and on the survival rate of piglets from birth to weaning. For this purpose, records of individual weight at birth and weaning of piglets obtained from a database of 295 Landrace litters born between 2000 and 2010 on a pig farm in the western region of the State of Paraná were used. The litters were classified as small (up to 7 piglets, medium (8 to 13 piglets, and large (> 14 piglets according to the total number of piglets born. The data were analyzed considering the effects of the year of sow mating and size class of the litter at birth. The correlations between mean weight and variance in litter weight and size were higher for medium and large litters. The size class of the litter significantly influenced the mean weight of piglets at birth and weaning and the variance in birth weight. Piglets born in medium and large litters weighed less and exhibited greater birth weight variation and a lower survival rate until weaning than piglets born in small litters.

  8. Effects of genotypic and phenotypic variation on establishment are important for conservation, invasion, and infection biology.

    Science.gov (United States)

    Forsman, Anders

    2014-01-01

    There is abundant evidence that the probability of successful establishment in novel environments increases with number of individuals in founder groups and with number of repeated introductions. Theory posits that the genotypic and phenotypic variation among individuals should also be important, but few studies have examined whether founder diversity influences establishment independent of propagule pressure, nor whether the effect is model or context dependent. I summarize the results of 18 experimental studies and report on a metaanalysis that provides strong evidence that higher levels of genotypic and phenotypic diversity in founder groups increase establishment success in plants and animals. The effect of diversity is stronger in experiments carried out under natural conditions in the wild than under seminatural or standardized laboratory conditions. The realization that genetic and phenotypic variation is key to successful establishment may improve the outcome of reintroduction and translocation programs used to vitalize or restore declining and extinct populations. Founder diversity may also improve the ability of invasive species to establish and subsequently spread in environments outside of their native community, and enhance the ability of pathogens and parasites to colonize and invade the environment constituted by their hosts. It is argued that exchange of ideas, methodological approaches, and insights of the role of diversity for establishment in different contexts may further our knowledge, vitalize future research, and improve management plans in different disciplines. PMID:24367109

  9. Atmospheric wave induced O2 and OH airglow intensity variations: effect of vertical wavelength and damping

    Directory of Open Access Journals (Sweden)

    D. Gobbi

    2011-04-01

    Full Text Available From nocturnal variations of the airglow O2 (0-1 and OH Meinel (6-2 band emission intensity and the rotational temperature, gravity waves and the damping effect in the MLT region were investigated. The data set was obtained from photometer measurements at Rikubetsu (43.5° N, 143.8° E, Japan, from March 2004 to August 2005. The ratio of the amplitude of oscillation and their phase difference between the two emissions were calculated when simultaneous periodic variations were observed. The ratio showed a linear correlation with the phase difference. The vertical wavelength and damping rate were estimated by using a model calculation carried out by previous works. The results show that the wave damping is significant when the vertical wavelength is shorter than 30–40 km. Krassovsky's parameter η, which represents a ratio between the emission intensity and temperature oscillations, was also calculated. The results show that the η also depends on the damping effect.

  10. Effects of dietary variation on growth, composition, and maturation of Manduca sexta (Sphingidae: Lepidoptera).

    Science.gov (United States)

    Ojeda-Avila, T; Woods, H Arthur; Raguso, R A

    2003-04-01

    Most studies linking dietary variation with insect fitness focus on a single dietary component and late larval growth. We examined the effects of variation in multiple dietary factors over most life stages of the sphingid moth, Manduca sexta. Larvae received artificial diets in which protein, sucrose, and water content were varied. The relationship between larval size, growth and consumption rates differed significantly across diets. Larvae on control and low-sucrose diets grew most rapidly and attained the largest pupal and adult sizes. Conversely, larvae on low-water and low-protein diets initially grew slowly, but accelerated in the fifth instar and became pupae and adults comparable to control animals in size. There were no fundamental differences in protein:carbohydrate consumption patterns or strategies among experimental diets and larval instars. However, inadequate dietary water appeared to be more important for early than late instar larvae. Larvae on all artificial diets showed increasing fat content throughout all stages, including wandering and metamorphosis. Compensatory feeding among low-water and low-protein larvae was correlated with significantly higher fat content in larvae, pupae and adults, whereas low-sucrose animals were substantially leaner than those on the control diet. These differences may have strong effects on adult physiology, reproduction, and foraging patterns. PMID:12769983

  11. Cosmological variation of the MOND constant: secular effects on galactic systems

    CERN Document Server

    Milgrom, Mordehai

    2014-01-01

    The proximity of the MOND acceleration constant with cosmological accelerations -- for example, a0~ cH0/2pi -- points to its possibly decreasing with cosmic time. I begin to consider the secular changes induced in galactic systems by such presumed variations, assumed adiabatic. It is important to understand these effects, in isolation from other evolutionary influences, in order to identify or constrain a0 variations by detection of induced effects, or lack thereof. I find that as long as the system is fully in the deep-MOND regime -- as applies to many galactic systems -- the adiabatic response of the system obeys simple scaling laws. For example, in a system that would be stationary for fixed a0, the system expands homologously as a0^{-1/4}, while internal velocities decrease uniformly as a0^{1/4}. If a0 is proportional to cH at all relevant times, this change amounts to a factor of ~ 2.5 since redshift 10. For a system stationary in a rotating frame, the angular frequency decreases as a0^{1/2}. The acceler...

  12. Dynamic Variation Characteristics of Phosphorus in Paddy Field Runoff in Saline Land and Its Potential Environmental Effect

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    [Objective] The aim was to study the dynamic variation characteristics of phosphorus in paddy field runoff in saline land and its potential environmental effect. [Method] Taking Qianguo irrigation district in soda-saline land in Songnen Plain as study object, the dynamic variation law of phosphorus in paddy field runoff under different irrigation conditions and its potential environmental effect were discussed. [Result] Surface water in paddy field was alkaline, and scattered soil had poor fertilizer conser...

  13. Description of light nuclei in pionless effective field theory using the stochastic variational method

    Science.gov (United States)

    Lensky, Vadim; Birse, Michael C.; Walet, Niels R.

    2016-09-01

    We construct a coordinate-space potential based on pionless effective field theory (EFT) with a Gaussian regulator. Charge-symmetry breaking is included through the Coulomb potential and through two- and three-body contact interactions. Starting with the effective field theory potential, we apply the stochastic variational method to determine the ground states of nuclei with mass number A ≤4 . At next-to-next-to-leading order, two out of three independent three-body parameters can be fitted to the three-body binding energies. To fix the remaining one, we look for a simultaneous description of the binding energy of 4He and the charge radii of 3He and 4He. We show that at the order considered we can find an acceptable solution, within the uncertainty of the expansion. We find that the EFT expansion shows good agreement with empirical data within the estimated uncertainty, even for a system as dense as 4He.

  14. Covariant variational approach to Yang-Mills Theory: effective potential of the Polyakov loop

    CERN Document Server

    Quandt, Markus

    2016-01-01

    We compute the effective action of the Polyakov loop in SU(2) and SU(3) Yang-Mills theory using a previously developed covariant variational approach. The formalism is extended to background gauge and it is shown how to relate the low order Green's functions to the ones in Landau gauge studied earlier. The renormalization procedure is discussed. The self-consistent effective action is derived and evaluated using the numerical solution of the gap equation. We find a clear signal for a deconfinement phase transition at finite temperatures, which is second order for SU(2) and first order for SU(3). The critical temperatures obtained are in reasonable agreement with high precision lattice data.

  15. Cohesive zone modelling of wafer bonding and fracture: effect of patterning and toughness variations

    International Nuclear Information System (INIS)

    Direct wafer bonding has increasingly become popular in the manufacture of microelectromechanical systems and semiconductor microelectronics components. The success of the bonding process is controlled by variables such as wafer flatness and surface preparation. In order to understand the effects of these variables, spontaneous planar crack propagation simulations were performed using the spectral scheme in conjunction with a cohesive zone model. The fracture-toughness on the bond interface is varied to simulate the effect of surface roughness (nanotopography) and patterning. Our analysis indicated that the energetics of crack propagation is sensitive to the local surface property variations. The patterned wafers are tougher (well bonded) than the unpatterned ones of the same average fracture-toughness

  16. Description of light nuclei in pionless effective field theory using the stochastic variational method

    CERN Document Server

    Lensky, Vadim; Walet, Niels R

    2016-01-01

    We construct a coordinate-space potential based on pionless effective field theory with a Gaussian regulator. Charge-symmetry breaking is included through the Coulomb potential and through two- and three-body contact interactions. Starting with the effective field theory potential, we apply the stochastic variational method to determine the ground states of nuclei with mass number $A\\leq 4$. At next-to-next-to-leading order, two out of three independent three-body parameters can be fitted to the three-body binding energies. To fix the remaining one, we look for a simultaneous description of the binding energy of $^4$He and the charge radii of $^3$He and $^4$He. We show that at the order considered we can find an acceptable solution, within the uncertainty of the expansion. We find that the EFT expansion shows good convergence, even for a system as dense as $^4$He.

  17. Length-scale effect due to periodic variation of geometrically necessary dislocation densities

    DEFF Research Database (Denmark)

    Oztop, M. S.; Niordson, Christian Frithiof; Kysar, J. W.

    2013-01-01

    of high spatial resolution diffraction methods in a scanning electron microscope give a much more quantitative understanding of plastic deformation at small length scales. Specifically, geometrically necessary dislocation densities (GND) can now be measured and provide detailed information about......Strain gradient plasticity theories have been successful in predicting qualitative aspects of the length scale effect, most notably the increase in yield strength and hardness as the size of the deforming volume decreases. However new experimental methodologies enabled by recent developments...... the microstructure of deformed metals in addition to the size effect. Recent GND measurements have revealed a distribution of length scales that evolves within a metal undergoing plastic deformation. Furthermore, these experiments have shown an accumulation of GND densities in cell walls as well as a variation...

  18. Clinical repercussions of Martin-Gruber anastomosis: anatomical study☆

    Science.gov (United States)

    Cavalheiro, Cristina Schmitt; Filho, Mauro Razuk; Pedro, Gabriel; Caetano, Maurício Ferreira; Vieira, Luiz Angelo; Caetano, Edie Benedito

    2016-01-01

    Objective The main objective of this study was to describe Martin-Gruber anastomosis anatomically and to recognize its clinical repercussions. Method 100 forearms of 50 adult cadavers were dissected in an anatomy laboratory. The dissection was performed by means of a midline incision along the entire forearm and the lower third of the upper arm. Two flaps including skin and subcutaneous tissue were folded back on the radial and ulnar sides, respectively. Results Nerve communication between the median and ulnar nerves in the forearm (Martin-Gruber anastomosis) was found in 27 forearms. The anastomosis was classified into six types: type I: anastomosis between the anterior interosseous nerve and the ulnar nerve (n = 9); type II: anastomosis between the anterior interosseous nerve and the ulnar nerve at two points (double anastomosis) (n = 2); type III: anastomosis between the median nerve and the ulnar nerve (n = 4); type IV: anastomosis between branches of the median nerve and ulnar nerve heading toward the flexor digitorum profundus muscle of the fingers; these fascicles form a loop with distal convexity (n = 5); type V: intramuscular anastomosis (n = 5); and type VI: anastomosis between a branch of the median nerve to the flexor digitorum superficialis muscle and the ulnar nerve (n = 2). Conclusion Knowledge of the anatomical variations relating to the innervation of the hand has great importance, especially with regard to physical examination, diagnosis, prognosis and surgical treatment. If these variations are not given due regard, errors and other consequences will be inevitable. PMID:27069892

  19. Effectiveness of biodiversity surrogates for conservation planning: different measures of effectiveness generate a kaleidoscope of variation.

    Directory of Open Access Journals (Sweden)

    Hedley S Grantham

    Full Text Available Conservation planners represent many aspects of biodiversity by using surrogates with spatial distributions readily observed or quantified, but tests of their effectiveness have produced varied and conflicting results. We identified four factors likely to have a strong influence on the apparent effectiveness of surrogates: (1 the choice of surrogate; (2 differences among study regions, which might be large and unquantified (3 the test method, that is, how effectiveness is quantified, and (4 the test features that the surrogates are intended to represent. Analysis of an unusually rich dataset enabled us, for the first time, to disentangle these factors and to compare their individual and interacting influences. Using two data-rich regions, we estimated effectiveness using five alternative methods: two forms of incidental representation, two forms of species accumulation index and irreplaceability correlation, to assess the performance of 'forest ecosystems' and 'environmental units' as surrogates for six groups of threatened species-the test features-mammals, birds, reptiles, frogs, plants and all of these combined. Four methods tested the effectiveness of the surrogates by selecting areas for conservation of the surrogates then estimating how effective those areas were at representing test features. One method measured the spatial match between conservation priorities for surrogates and test features. For methods that selected conservation areas, we measured effectiveness using two analytical approaches: (1 when representation targets for the surrogates were achieved (incidental representation, or (2 progressively as areas were selected (species accumulation index. We estimated the spatial correlation of conservation priorities using an index known as summed irreplaceability. In general, the effectiveness of surrogates for our taxa (mostly threatened species was low, although environmental units tended to be more effective than forest ecosystems

  20. Gate line edge roughness amplitude and frequency variation effects on intra die MOS device characteristics

    Science.gov (United States)

    Hamadeh, Emad; Gunther, Norman G.; Niemann, Darrell; Rahman, Mahmud

    2006-06-01

    Random fluctuations in fabrication process outcomes such as gate line edge roughness (LER) give rise to corresponding fluctuations in scaled down MOS device characteristics. A thermodynamic-variational model is presented to study the effects of LER on threshold voltage and capacitance of sub-50 nm MOS devices. Conceptually, we treat the geometric definition of the MOS devices on a die as consisting of a collection of gates. In turn, each of these gates has an area, A, and a perimeter, P, defined by nominally straight lines subject to random process outcomes producing roughness. We treat roughness as being deviations from straightness consisting of both transverse amplitude and longitudinal wavelength each having lognormal distribution. We obtain closed-form expressions for variance of threshold voltage ( Vth), and device capacitance ( C) at Onset of Strong Inversion (OSI) for a small device. Using our variational model, we characterized the device electrical properties such as σ and σC in terms of the statistical parameters of the roughness amplitude and spatial frequency, i.e., inverse roughness wavelength. We then verified our model with numerical analysis of Vth roll-off for small devices and σ due to dopant fluctuation. Our model was also benchmarked against TCAD of σ as a function of LER. We then extended our analysis to predict variations in σ and σC versus average LER spatial frequency and amplitude, and oxide-thickness. Given the intuitive expectation that LER of very short wavelengths must also have small amplitude, we have investigated the case in which the amplitude mean is inversely related to the frequency mean. We compare with the situation in which amplitude and frequency mean are unrelated. Given also that the gate perimeter may consist of different LER signature for each side, we have extended our analysis to the case when the LER statistical difference between gate sides is moderate, as well as when it is significantly large.

  1. Validation of CFD Simulations of Cerebral Aneurysms With Implication of Geometric Variations

    OpenAIRE

    Hoi, Yiemeng; Woodward, Scott H.; Kim, Minsuok; Taulbee, Dale B.; Meng, Hui

    2006-01-01

    Computational fluid dynamics (CFD) simulations using medical-image-based anatomical vascular geometry are now gaining clinical relevance. This study aimed at validating the CFD methodology for studying cerebral aneurysms by using particle image velocimetry (PIV) measurements, with a focus on the effects of small geometric variations in aneurysm models on the flow dynamics obtained with CFD. Method of Approach. An experimental phantom was fabricated out of silicone elastomer to best mimic a sp...

  2. Evaluation of predictors for anatomical success in macular hole surgery in Indian population

    Directory of Open Access Journals (Sweden)

    Atul Kumar

    2014-01-01

    Full Text Available Purpose: The aim was to evaluate outcomes and predictors for anatomical success in macular hole (MH surgery. Materials and Methods: This was a prospective cohort study of patients operated for idiopathic MH with stages II, III or IV. Patients underwent pars plana vitrectomy with internal limiting membrane (ILM peeling, internal gas tamponade, and postoperative face down positioning. The primary outcome measure was anatomical closure of MH, while secondary outcome measure was postoperative external limiting membrane (ELM continuity. Effect of MH size, duration of MH, size of ILM peel, type of gas tamponade (SF6 vs. C3F8 and macular hole index (MHI on anatomical MH closure was also evaluated. Results: Of the 62 eyes operated, anatomical closure of MH was achieved in 55 eyes (88.7%. The median duration of follow-up was 8 months (range: 6-15 months. Mean BVCA improved from 0.94 ± 0.26 at baseline to 0.40 ± 0.23 logMAR at last follow-up (P = 0.01. There was a statistically significant association between size of ILM peel and anatomical closure of MH (P = 0.04. Duration of symptoms, size of MH, type of gas tamponade, MHI had no effect on anatomical closure (P = 0.22, 0.28, 0.40 respectively, Chi-square test. Postoperative continuity of the ELM was significantly associated with a shorter symptom duration (<6 months before surgery. Conclusion: Acceptable anatomical closure could be attained with the defined technique. Size of ILM peel is a new predictor of anatomical success while symptom duration affects postoperative ELM continuity.

  3. Scalenus minimus muscle: overestimated or not? An anatomical study.

    Science.gov (United States)

    Natsis, Konstantinos; Totlis, Trifon; Didagelos, Matthaios; Tsakotos, George; Vlassis, Konstantinos; Skandalakis, Panagiotis

    2013-04-01

    The wide range of scalenus minimus muscle incidence reported in the literature along with the plethora of fibromuscular structures that may appear in the interscalene triangle, having various terminologies, were the reasons to conduct the present study questioning the reported high incidence of this supernumerary scalene muscle. Seventy-three Greek cadavers were dissected and examined for the presence of a scalenus minimus muscle. It was found unilaterally in three of 73 (4.11%) cadavers studied. The literature review, concerning its incidence, revealed a wide range between 7.8 and 71.7 per cent, which cannot be attributed only to racial variation. Thus, there is a matter whether other variations of the scalene muscles are considered as a true scalenus minimus muscle. Recognition of this muscle is important not only for anatomists, but also has clinical significance for the diagnosis of the thoracic outlet syndrome. Surgeons performing scalenectomy and anesthesiologists during interscalene brachial plexus block should keep in mind the anatomical variations of this region.

  4. Effective elastic thickness variations along the Andean margin and their relationship to subduction geometry

    Science.gov (United States)

    PéRez-Gussinyé, M.; Lowry, A. R.; Phipps Morgan, J.; Tassara, A.

    2008-02-01

    We present a new map of the spatial variations in effective elastic thickness, Te, along the Andes estimated using Bouguer coherence. The Te variations reflect interactions between subducting slab and preexisting terrane structure. In the forearc, conductive cooling of the continent by the subducting slab exerts primary control on rigidity, resulting in Te that is highest (˜40 km) where the oceanic lithosphere is oldest and coldest (˜20°S). In the central Andes, Te is relatively low (˜20 km) along the volcanic chain and the Altiplano and Puna plateaus. We interpret this weakening to reflect a high geothermal gradient maintained by advective magmatic processes, a shallow and hot asthenosphere, and a very weak lower crust throughout this region. East of the plateaus, high Te delineates underthrusting of the Brazilian shield. Finally, north and south of the plateaus, flat subduction areas are characterized by high Te, high shear wave velocity, thick thermal lithosphere, and low heat flow, indicating that continental lithosphere there is thicker, colder, and stronger. On the basis of these relationships we suggest that variations in slab dip along the margin relate to variations in structure of the continental lithosphere. In particular, we propose that upper plate structure influences the width and viscosity of the asthenospheric wedge, which control the suction moment responsible for the subduction angle at depths ≥70-100 km. For example, when oceanic lithosphere subducts beneath thin continental lithosphere, the low-viscosity asthenosphere allows the slab to detach from the continent and sink into the mantle at normal angles. However, when oceanic lithosphere subducts close or beneath thick and strong continental lithosphere, the asthenospheric wedge narrows and corner flow drags high-viscosity mantle from the base of the thick (>150 km), cold continent into the wedge. Suction forces increase with both narrowing of the wedge and its increasing viscosity. We

  5. Effects of climatic variation on field metabolism and water relations of desert tortoises

    Science.gov (United States)

    Henen, B.T.; Peterson, C.C.; Wallis, I.R.; Berry, K.H.; Nagy, K.A.

    1998-01-01

    We used the doubly labeled water method to measure the field metabolic rates (FMRs, in kJ kg-1 day-1) and water flux rates (WIRs, in ml H2O kg-1 day-1) of adult desert tortoises (Gopherus agassizii) in three parts of the Mojave Desert in California over a 3.5-year period, in order to develop insights into the physiological responses of this threatened species to climate variation among sites and years. FMR, WIR, and the water economy index (WEI, in ml H2O kJ-1, an indicator of drinking of free water) differed extensively among seasons, among study sites, between sexes, and among years. In high-rainfall years, males had higher FMRs than females. Average daily rates of energy and water use by desert tortoises were extraordinarily variable: 28-fold differences in FMR and 237-fold differences in WIR were measured. Some of this variation was due to seasonal conditions, with rates being low during cold winter months and higher in the warm seasons. However, much of the variation was due to responses to year-to-year variation in rainfall. Annual spring peaks in FMR and WIR were higher in wet years than in drought years. Site differences in seasonal patterns were apparently due to geographic differences in rainfall patterns (more summer rain at eastern Mojave sites). In spring 1992, during an El Nino (ENSO) event, the WEI was greater than the maximal value obtainable from consuming succulent vegetation, indicating copious drinking of rainwater at that time. The physiological and behavioral flexibility of desert tortoises, evident in individuals living at all three study sites, appears central to their ability to survive droughts and benefit from periods of resource abundance. The strong effects of the El Nino (ENSO) weather pattern on tortoise physiology, reproduction, and survival elucidated in this and other studies suggest that local manifestations of global climate events could have a long-term influence on the tortoise populations in the Mojave Desert.

  6. Spatial variations of effective elastic thickness of the Lithosphere in the Southeast Asia regions

    Science.gov (United States)

    Shi, Xiaobin; Kirby, Jon; Yu, Chuanhai; Swain, Chris; Zhao, Junfeng

    2016-04-01

    The effective elastic thickness Te corresponds to the thickness of an idealized elastic beam that would bend similarly to the actual lithosphere under the same applied loads, and could provide important insight into rheology and state of stress. Thus, it is helpful to improve our understanding of the relationship between tectonic styles, distribution of earthquakes and lithospheric rheology in various tectonic settings. The Southeast Asia, located in the southeastern part of the Eurasian Plate, comprises a complex collage of continental fragments, volcanic arcs, and suture zones and marginal oceanic basins, and is surrounded by tectonically active margins which exhibit intense seismicity and volcanism. The Cenozoic southeastward extrusion of the rigid Indochina Block due to the Indo-Asian collision resulted in the drastic surface deformation in the western area. Therefore, a high resolution spatial variation map of Te might be a useful tool for the complex Southeast Asia area to examine the relationships between surface deformation, earthquakes, lithospheric structure and mantle dynamics. In this study, we present a high-resolution map of spatial variations of Te in the Southeast Asia area using the wavelet method, which convolves a range of scaled wavelets with the two data sets of Bouguer gravity anomaly and topography. The topography and bathymetry grid data was extracted from the GEBCO_08 Grid of GEBCO digital atlas. The pattern of Te variations agrees well with the tectonic provinces in the study area. On the whole, low lithosphere strength characterizes the oceanic basins, such as the South China Sea, the Banda sea area, the Celebes Sea, the Sulu Sea and the Andaman Sea. Unlike the oceanic basins, the continental fragments show a complex pattern of Te variations. The Khorat plateau and its adjacent area show strong lithosphere characteristics with a Te range of 20-50 km, suggesting that the Khorat plateau is the strong core of the Indochina Block. The West

  7. Effects of seed traits variation on seedling performance of the invasive weed, Ambrosia artemisiifolia L.

    Science.gov (United States)

    Ortmans, William; Mahy, Grégory; Monty, Arnaud

    2016-02-01

    Seedling performance can determine the survival of a juvenile plant and impact adult plant performance. Understanding the factors that may impact seedling performance is thus critical, especially for annuals, opportunists or invasive plant species. Seedling performance can vary among mothers or populations in response to environmental conditions or under the influence of seed traits. However, very few studies have investigated seed traits variations and their consequences on seedling performance. Specifically, the following questions have been addressed by this work: 1) How the seed traits of the invasive Ambrosia artemisiifolia L. vary among mothers and populations, as well as along the latitude; 2) How do seed traits influence seedling performance; 3) Is the influence on seedlings temperature dependent. With seeds from nine Western Europe ruderal populations, seed traits that can influence seedling development were measured. The seeds were sown into growth chambers with warmer or colder temperature treatments. During seedling growth, performance-related traits were measured. A high variability in seed traits was highlighted. Variation was determined by the mother identity and population, but not latitude. Together, the temperature, population and the identity of the mother had an effect on seedling performance. Seed traits had a relative impact on seedling performance, but this did not appear to be temperature dependent. Seedling performance exhibited a strong plastic response to the temperature, was shaped by the identity of the mother and the population, and was influenced by a number of seed traits.

  8. Environmental Factors Effect on Stem Radial Variations of Picea crassifolia in Qilian Mountains, Northwestern China

    Directory of Open Access Journals (Sweden)

    Wenbin Wang

    2016-09-01

    Full Text Available Picea crassifolia Komarov (Qinghai spruce is an endemic tree species in China and is widespread in the Qilian Mountains, in northwestern China. High temporal resolution changes of Qinghai spruce tree stem growth remain poorly investigated and the relationships between the species growth and climate are still not completely understood. In this study, we assessed the daily and seasonal stem radial variations, and analyzed the relationships between stem radial increment of Qinghai spruce and environmental factors during the main growing period (June–August. We have found that the stem radial variations of Qinghai spruce can be divided into three phases according to the air temperature and that Qinghai spruce has two diurnal cycle patterns. The main growing period of Qinghai spruce is 30 May–31 August according to micro-core measurements, in conformity with the daily mean air temperature keeping above 5 °C. Precipitation and relative humidity have positive effects on the growth of Qinghai spruce, and we develop a multiple linear regression model that can explain 63% of the stem radial increment over the main growing period.

  9. Effect of compositional variations in the lead lanthanum zirconate stannate titanate system on electrical properties

    International Nuclear Information System (INIS)

    The purpose of this work was to evaluate the effect of compositional modifications on the electrical properties of lead lanthanum zirconate stannate titanate (PLZST) ceramics, as well as to examine their electrically induced phase-change behavior. Variations in the Ti:Sn ratio were evaluated. Increased Ti4+ content produced the following: decreased switching field, related to an increased antiferroelectric-ferroelectric (AFE-FE) transition temperature; constant hysteresis (ΔE) correlated with a constant temperature of the maximum dielectric constant (Tmax); a sharper dielectric-constant maximum peak; and increased room-temperature dielectric constant (K). Variations in the Zr:Sn ratio also were evaluated. Increased Zr4+ content produced the following: increased hysteresis with increased Tmax, decreased maximum dielectric constant, and decreased switching field with increased AFE-FE transition temperature (TAFE-FE). From these results, with respect to compositional modifications, the AFE-FE switching field (EAFE-FE) and ΔE were observed to be dependent strongly on TAFE-FE and Tmax, respectively. Negligible change existed in the strain achievable at the switching field, which remained constant for all compositions at ∼0.16%. The significance of this research was the ability demonstrated to tailor the properties of phase-change materials through compositional modifications

  10. Effects of life history variation on vertical transfer of toxicants in marine mammals.

    Science.gov (United States)

    Noonburg, Erik G; Nisbet, Roger M; Klanjscek, Tin

    2010-05-21

    Toxicant bioaccumulation poses a risk to many marine mammal populations. Although individual-level toxicology has been the subject of considerable research in several species, we lack a theoretical framework to generalize the results across environments and life histories. Here we formulate a dynamic energy budget model to predict the effects of intra- and interspecific life history variation on toxicant dynamics in marine mammals. Dynamic energy budget theory attempts to describe the most general processes of energy acquisition and utilization in heterotrophs. We tailor the basic model to represent the marine mammal reproductive cycle, and we add a model of toxicant uptake and partitioning to describe vertical transfer of toxicants from mother to offspring during gestation and lactation. We first show that the model predictions are consistent with qualitative patterns reported in empirical studies and previous species-specific modeling studies. Next, we use this model to examine the dependence of offspring toxicant load on birth order, food density, and interspecific life history variation. PMID:20171232

  11. Effect of Heavy Metals Pollution on Soil Microbial Diversity and Bermudagrass Genetic Variation

    Science.gov (United States)

    Xie, Yan; Fan, Jibiao; Zhu, Weixi; Amombo, Erick; Lou, Yanhong; Chen, Liang; Fu, Jinmin

    2016-01-01

    Heavy metal pollution is a serious global environmental problem as it adversely affects plant growth and genetic variation. It also alters the composition and activity of soil microbial communities. The objectives of this study were to determine the soil microbial diversity, bermudagrass genetic variation in Cd contaminated or uncontaminated soils from Hunan province of China, and to evaluate Cd-tolerance of bermudagrass at different soils. The Biolog method, hydroponic experiments and simple sequence repeat markers were used to assess the functional diversity of microorganisms, Cd-tolerance and the genetic diversity of bermudagrass, respectively. Four of the sampling sites were heavily contaminated with heavy metals. The total bioactivity, richness, and microbial diversity decreased with increasing concentration of heavy metal. The hydroponic experiment revealed that bermudagrass populations collected from polluted sites have evolved, encompassing the feature of a higher resistance to Cd toxicity. Higher genetic diversity was observed to be more in contaminated populations than in uncontaminated populations. Heavy metal pollution can result in adverse effects on plant growth, soil microbial diversity and activity, and apparently has a stronger impact on the genetic structure. The results of this study provide new insights and a background to produce a genetic description of populations in a species that is suitable for use in phytoremediation practices. PMID:27303431

  12. Cosmological variation of the fine structure constant from an ultralight scalar field: The effects of mass

    Science.gov (United States)

    Gardner, Carl L.

    2003-08-01

    Cosmological variation of the fine structure constant α due to the evolution of a spatially homogeneous ultralight scalar field (m˜H0) during the matter and Λ dominated eras is analyzed. Agreement of Δα/α with the value suggested by recent observations of quasar absorption lines is obtained by adjusting a single parameter, the coupling of the scalar field to matter. Asymptotically α(t) in this model goes to a constant value α¯≈α0 in the early radiation and the late Λ dominated eras. The coupling of the scalar field to (nonrelativistic) matter drives α slightly away from α¯ in the epochs when the density of matter is important. Simultaneous agreement with the more restrictive bounds on the variation |Δα/α| from the Oklo natural fission reactor and from meteorite samples can be achieved if the mass of the scalar field is on the order of 0.5 0.6 HΛ, where HΛ=Ω1/2ΛH0. Depending on the scalar field mass, α may be slightly smaller or larger than α0 at the times of big bang nucleosynthesis, the emission of the cosmic microwave background, the formation of early solar system meteorites, and the Oklo reactor. The effects on the evolution of α due to nonzero mass for the scalar field are emphasized. An order of magnitude improvement in the laboratory technique could lead to a detection of (α˙/α)0.

  13. Enhanced effect of quark mass variation in 229Th and limits from Oklo data

    CERN Document Server

    Flambaum, V V

    2008-01-01

    The effects of the variation of the dimensionless strong interaction parameter Xq=mq/Lambda{QCD} (mq is the quark mass, Lambda{QCD} is the QCD scale) are enhanced about 1.5 x 10**5 times in the 7.6 eV "nuclear clock" transition between the ground and first excited states in the 229Th nucleus and about 1 x 10**8 times in the relative shift of the 0.1 eV compound resonance in 150Sm.The best terrestrial limit on the temporal variation of the fundamental constants, |delta(Xq)/Xq| < 4 x 10**-9 at 1.8 billion years ago (|d(Xq/Xq)/dt| < 2.2 x 10**-18 y**-1), is obtained from the shift of this Sm resonance derived from the Oklo natural nuclear reactor data. The results for 229Th and 150Sm are obtained by extrapolation from light nuclei where the many-body calculations can be performed more accurately. The errors produced by such extrapolation may be smaller than the errors of direct calculations in heavy nuclei. The extrapolation results are compared with the "direct" estimates obtained using the Walecka model....

  14. Increased interstitial loading reduces the effect of microstructural variations in cardiac tissue.

    Science.gov (United States)

    Hubbard, Marjorie Letitia; Henriquez, Craig S

    2010-04-01

    Electrical propagation in diseased and aging hearts is strongly influenced by structural changes that occur in both the intracellular and interstitial spaces of cardiac tissue; however, very few studies have investigated how interactions between the two spaces affect propagation at the microscale. In this study, we used one-dimensional microstructural computer models of interconnected ventricular myocytes to systematically investigate how increasing the effective interstitial resistivity (rho(oeff)) influences action potential propagation in fibers with variations in intracellular properties such as cell coupling and cell length. Changes in rho(oeff) were incorporated into a monodomain model using a correction to the intracellular properties that was based on bidomain simulations. The results showed that increasing rho(oeff) in poorly coupled one-dimensional fibers alters the distribution of electrical load at the microscale and causes propagation to become more continuous. In the poorly coupled fiber, this continuous state is characterized by decreased gap junction delay, sustained conduction velocity, increased sodium current, reduced maximum upstroke velocity, and increased safety factor. Long, poorly coupled cells experience greater loading effects than short cells and show the greatest initial response to changes in rho(oeff). In inhomogeneous fibers with adjacent well-coupled and poorly coupled regions, increasing rho(oeff) in the poorly coupled region also reduces source-load mismatch, which delays the onset of conduction block and reduces the dispersion of repolarization at the transition between the two regions. Increasing the rho(oeff) minimizes the effect of cell-to-cell variations and may influence the pattern of activation in critical regimes characterized by low intercellular coupling, microstructural heterogeneity, and reduced or abnormal membrane excitability. PMID:20097772

  15. Juvenile survival in a tropical population of roseate terns: Interannual variation and effect of tick parasitism

    Science.gov (United States)

    Monticelli, D.; Ramos, J.A.; Hines, J.E.; Nichols, J.D.; Spendelow, J.A.

    2008-01-01

    Many demographic studies on long-lived seabirds have focused on the estimation of adult survival, but much less is known about survival during the early years of life, especially in tropical species. We report analyses of a capture?recapture dataset of 685 roseate terns ringed as fledglings and adults between 1998 and 2005 on Aride Island, Seychelles, and recaptured/resighted at the same colony site over a 5 yr (2002 to 2006) period. A multistate model was used to estimate survival for different age classes, including juvenile (first-year) birds returning as non-breeding prospectors. The effect of infestation by parasites (ticks) on survival was also examined. Overall, the estimated return of first-year individuals to the natal colony was very variable, ranging from 2 to 22%. Conditioned on survival, the probability of returning from Age 2 yr onwards increased to 70%. Survival rates were best modeled as time-specific, with estimates varying from 0.02 to 1.00 (mean 0.69) in first-year birds with a marked negative effect of tick infestation. In older birds (minimum age of 2 yr), the annual estimates fell between 0.69 and 0.86 (mean 0.77). Using a components of variance approach for estimation of year-to-year variation, we found high temporal variability for first-year individuals (coefficient of variation [CV] = 65%) compared to much less variation in the survival rate of older birds (CV = 9%). These findings agree with the life-history prediction that demographic rates of juveniles are usually lower and more variable than those of older individuals. Our results are also consistent with the predicted negative effect of tick parasitism on juvenile survival. Compared with data from other roseate tern populations, survival over the first 2 yr (Age 0 to 2 yr) was 18 to 40% higher in this study, suggesting that a high `young? survival rate may be an important demographic trait in this tropical population to compensate for the low annual reproductive success. Our data show

  16. The Effect of String Tension Variation on the Perceived Pitch of a Classical Guitar

    Directory of Open Access Journals (Sweden)

    Wanda Jadwiga Lewis

    2014-09-01

    Full Text Available Actual motion of a vibrating guitar string is a superposition of many possible shapes (modes in which it could vibrate. Each of these modes has a corresponding frequency, and the lowest frequency is associated with a shape idealised as a single wave, referred to as the fundamental mode. The other contributing modes, each with their own progressively higher frequency, are referred to as overtones, or harmonics. By attaching a string to a medium (a soundboard capable of a response to the vibrating string, sound waves are generated. The sound heard is dominated by the fundamental mode, ‘coloured’ by contributions from the overtones, as explained by the classical theory of vibration. The classical theory, however, assumes that the string tension remains constant during vibration, and this cannot be strictly true; when considering just the fundamental mode, string tension will reach two maximum changes, as it oscillates up and down. These changes, occurring twice during the fundamental period match the frequency of the octave higher, 1st overtone. It is therefore plausible to think that the changing tension effect, through increased force on the bridge and, therefore, greater soundboard deflection, could be amplifying the colouring effect of (at least the 1st overtone.In this paper, we examine the possible influence of string tension variation on tonal response of a classical guitar. We use a perturbation model based on the classical result for a string in general vibration in conjunction with a novel method of assessment of plucking force that incorporates the engineering concept of geometric stiffness, to assess the magnitude of the normal force exerted by the string on the bridge. The results of our model show that the effect of tension variation is significantly smaller than that due to the installed initial static tension, and affects predominantly the force contribution arising from the fundamental mode. We, therefore, conclude that string

  17. ANATOMIC RESEARCH OF SUPERIOR CLUNIAL NERVE TRAUMA

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    In order to find the mechanism of superior clunial nerve (SCN) trauma, we dissected and revealed SCN from 12 corpses (24 sides). Combining 100 sides of SCN trauma, we inspected the course of SCN, the relation between SCN and it's neighbour tissues with the situation of SCN when being subjected to force. We found that the following special anatomic characteristics and mechanical elements such as the course of SCN, it's turning angles, the bony fibrous tube at the iliac crest, the posterior layer of the lumbodorsal fascia and SCN neighbour adipose tissue, are the causes of external force inducing SCN trauma. The anatomic revealment is the guidance of SCN trauma treatment with edged needle.

  18. Integrating anatomical pathology to the healthcare enterprise.

    Science.gov (United States)

    Daniel-Le Bozec, Christel; Henin, Dominique; Fabiani, Bettina; Bourquard, Karima; Ouagne, David; Degoulet, Patrice; Jaulent, Marie-Christine

    2006-01-01

    For medical decisions, healthcare professionals need that all required information is both correct and easily available. We address the issue of integrating anatomical pathology department to the healthcare enterprise. The pathology workflow from order to report, including specimen process and image acquisition was modeled. Corresponding integration profiles were addressed by expansion of the IHE (Integrating the Healthcare Enterprise) initiative. Implementation using respectively DICOM Structured Report (SR) and DICOM Slide-Coordinate Microscopy (SM) was tested. The two main integration profiles--pathology general workflow and pathology image workflow--rely on 13 transactions based on HL7 or DICOM standard. We propose a model of the case in anatomical pathology and of other information entities (orders, image folders and reports) and real-world objects (specimen, tissue samples, slides, etc). Cases representation in XML schemas, based on DICOM specification, allows producing DICOM image files and reports to be stored into a PACS (Picture Archiving and Communication System. PMID:17108550

  19. ACCESSORY SPLEEN: A CLINICALLY RELEVANT ANATOMIC ANOMALY

    OpenAIRE

    Prachi Saffar; Amit Kumar; Ankur

    2016-01-01

    The purpose of our study is to emphasize on the clinical relevance of the presence of accessory spleen. It is not only a well-documented anatomic anomaly, it holds special significance in the differential diagnosis of intra-abdominal tumours and lymphadenopathy. MATERIALS AND METHODS Thirty male cadavers from North Indian population above the age of 60 yrs. were dissected in the Anatomy Department of FMHS, SGT University, Gurgaon, over a period of 5 yrs. (Sep 2010-Aug 2015) and presence...

  20. Pure endoscopic endonasal odontoidectomy: anatomical study

    OpenAIRE

    Messina, Andrea; Bruno, Maria Carmela; Decq, Philippe; Coste, Andre; Cavallo, Luigi Maria; de Divittis, Enrico; Cappabianca, Paolo; Tschabitscher, Manfred

    2007-01-01

    Different disorders may produce irreducible atlanto-axial dislocation with compression of the ventral spinal cord. Among the surgical approaches available for a such condition, the transoral resection of the odontoid process is the most often used. The aim of this anatomical study is to demonstrate the possibility of an anterior cervico-medullary decompression through an endoscopic endonasal approach. Three fresh cadaver heads were used. A modified endonasal endoscopic approach was made in al...

  1. Exploring brain function from anatomical connectivity

    Directory of Open Access Journals (Sweden)

    Gorka eZamora-López

    2011-06-01

    Full Text Available The intrinsic relationship between the architecture of the brain and the range of sensory and behavioral phenomena it produces is a relevant question in neuroscience. Here, we review recent knowledge gained on the architecture of the anatomical connectivity by means of complex network analysis. It has been found that corticocortical networks display a few prominent characteristics: (i modular organization, (ii abundant alternative processing paths and (iii the presence of highly connected hubs. Additionally, we present a novel classification of cortical areas of the cat according to the role they play in multisensory connectivity. All these properties represent an ideal anatomical substrate supporting rich dynamical behaviors, as-well-as facilitating the capacity of the brain to process sensory information of different modalities segregated and to integrate them towards a comprehensive perception of the real world. The result here exposed are mainly based in anatomical data of cats’ brain, but we show how further observations suggest that, from worms to humans, the nervous system of all animals might share fundamental principles of organization.

  2. Shape analysis of simulated breast anatomical structures

    Science.gov (United States)

    Contijoch, Francisco; Lynch, Jennifer M.; Pokrajac, David D.; Maidment, Andrew D. A.; Bakic, Predrag R.

    2012-03-01

    Recent advances in high-resolution 3D breast imaging, namely, digital breast tomosynthesis and dedicated breast CT, have enabled detailed analysis of the shape and distribution of anatomical structures in the breast. Such analysis is critically important, since the projections of breast anatomical structures make up the parenchymal pattern in clinical images which can mask the existing abnormalities or introduce false alarms; the parenchymal pattern is also correlated with the risk of cancer. As a first step towards the shape analysis of anatomical structures in the breast, we have analyzed an anthropomorphic software breast phantom. The phantom generation is based upon the recursive splitting of the phantom volume using octrees, which produces irregularly shaped tissue compartments, qualitatively mimicking the breast anatomy. The shape analysis was performed by fitting ellipsoids to the simulated tissue compartments. The ellipsoidal semi-axes were calculated by matching the moments of inertia of each individual compartment and of an ellipsoid. The distribution of Dice coefficients, measuring volumetric overlap between the compartment and the corresponding ellipsoid, as well as the distribution of aspect ratios, measuring relative orientations of the ellipsoids, were used to characterize various classes of phantoms with qualitatively distinctive appearance. A comparison between input parameters for phantom generation and the properties of fitted ellipsoids indicated the high level of user control in the design of software breast phantoms. The proposed shape analysis could be extended to clinical breast images, and used to inform the selection of simulation parameters for improved realism.

  3. Anatomical MRI with an atomic magnetometer

    CERN Document Server

    Savukov, I

    2012-01-01

    Ultra-low field (ULF) MRI is a promising method for inexpensive medical imaging with various additional advantages over conventional instruments such as low weight, low power, portability, absence of artifacts from metals, and high contrast. Anatomical ULF MRI has been successfully implemented with SQUIDs, but SQUIDs have the drawback of cryogen requirement. Atomic magnetometers have sensitivity comparable to SQUIDs and can be in principle used for ULF MRI to replace SQUIDs. Unfortunately some problems exist due to the sensitivity of atomic magnetometers to magnetic field and gradients. At low frequency, noise is also substantial and a shielded room is needed for improving sensitivity. In this paper, we show that at 85 kHz, the atomic magnetometer can be used to obtain anatomical images. This is the first demonstration of any use of atomic magnetometers for anatomical MRI. The demonstrated resolution is 1.1x1.4 mm2 in about six minutes of acquisition with SNR of 10. Some applications of the method are discuss...

  4. Circadian Variation in the Response to Experimental Endotoxemia and Modulatory Effects of Exogenous Melatonin

    DEFF Research Database (Denmark)

    Alamili, Mahdi; Klein, Mads; Lykkesfeldt, Jens;

    2013-01-01

    Disturbances in circadian rhythms are commonly observed in the development of several medical conditions and may also be involved in the pathophysiology of sepsis. Melatonin, with its antioxidative and anti-inflammatory effects, is known to modulate the response to endotoxemia. In this paper, we...... investigated the circadian variation with or without melatonin administration in an experimental endotoxemia model based on lipopolysaccharide (LPS). Sixty male Sprague-Dawley rats were assigned to six groups receiving an intraperitoneal injection of either LPS (5 mg/kg), LPS + melatonin (1 mg/kg), or LPS...... + melatonin (10 mg/kg) at either daytime or nighttime. Superoxide dismutase (SOD) was analyzed in liver samples collected after decapitation. Furthermore, inflammatory plasma markers (cytokines interleukin [IL]-6, IL-10) and oxidative plasma markers (ascorbic acid [AA], dehydroascorbic acid [DHA], and...

  5. The Effects of Temperature, Pressure, and Humidity Variations on 100 Meter Sprint Performances

    CERN Document Server

    Mureika, J R

    2005-01-01

    It is well known that ``equivalent'' sprint race times run with different accompanying wind speeds or at different altitudes are anything but equivalent races. The drag force acting on a sprinter is a function of air density and the relative wind speed, where the former has traditionally been calculated using the race venue's elevation above sea level. However, air density variation is dependent on more than just altitude. This work will quantify how changes in air temperature, barometric pressure, and humidity levels influence 100 m sprint performances. When these effects are considered in combination, the corrections to performances can be very large. The results suggest that a non-negligible difference in race times can be expected for ``equivalent'' performances run with the same wind speed at the same venue or physical altitude, but under different atmospheric conditions.

  6. Effect of atomization gas pressure variation on gas flow field in supersonic gas atomization

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    In this paper, a computational fluid flow model was adopted to investigate the effect of varying atomization gas pressure (P0) on the gas flow field in supersonic gas atomization. The influence of P0 on static pressure and velocity magnitude of the central axis of the flow field was also examined. The numerical results indicate that the maximum gas velocity within the gas field increases with increasing P0. The aspiration pressure (ΔP) is found to decrease as P0 increases at a lower atomization gas pressure. However, at a higher atomization gas pressure increasing P0 causes the opposite: the higher atomization gas pressure, the higher aspiration pressure. The alternation of ΔP is caused by the variations of stagnation point pressure and location of Mach disk, while hardly by the location of stagnation point. A radical pressure gradient is formed along the tip of the delivery tube and increases as P0 increases.

  7. Enhanced effect of quark mass variation in {sup229}Th and limits from Oklo data.

    Energy Technology Data Exchange (ETDEWEB)

    Flambaum, V. V.; Wiringa, R. B.; Physics; Univ. of New South Wales; Perimeter Inst. for Theoretical Physics

    2009-01-01

    The effects of the variation of the dimensionless strong interaction parameter X{sub q} = m{sub q}/{Lambda}{sub QCD} (m{sub q} is the quark mass, {Lambda}{sub QCD} is the QCD scale) are enhanced about 1.5 x 10{sup 5} times in the 7.6 eV 'nuclear clock' transition between the ground and first excited states in the {sup 229}Th nucleus and about 1 x 10{sup 8} times in the relative shift of the 0.1 eV compound resonance in {sup 150}Sm. The best terrestrial limit on the temporal variation of the fundamental constants, |{delta}X{sub q}/X{sub q}| < 4 x 10{sup -9} at 1.8 billion years ago (|X{sub q}/X{sub q}| < 2.2 x 10{sup -18}y{sup -1}), is obtained from the shift of this Sm resonance derived from the Oklo natural nuclear reactor data. The results for {sup 229}Th and {sup 150}Sm are obtained by extrapolation from light nuclei where the many-body calculations can be performed more accurately. The errors produced by such extrapolation may be smaller than the errors of direct calculations in heavy nuclei. The extrapolation results are compared with the 'direct' estimates obtained using the Walecka model. A number of numerical relations needed for the calculations of the variation effects in nuclear physics and atomic spectroscopy have been obtained: for the nuclear binding energy {delta} E/E {approx} -1.45 {delta}m{sub q}/m{sub q}, for the spin-orbit intervals {delta}E{sub so}/E{sub so} {approx} -0.22 {delta}m{sub q}/m{sub q}, for the nuclear radius {delta}r/r {approx} 0.3 {delta}m{sub q}/m{sub q} (in units of {Lambda}{sub QCD}); for the shifts of nuclear resonances and weakly bound energy levels {delta}E{sub r} {approx} 10 {delta}X{sub q}/X{sub q} MeV.

  8. Ammonium Variational Trends and the Ammonia Neutralization Effect on Acid Rain over East Asia

    Institute of Scientific and Technical Information of China (English)

    GAO Chao; WANG Zi-Fa; Enagnon A. GBAGUIDI

    2010-01-01

    The distribution and variations of ammonium and the ammonia neutralization effect on acid rain were examined in East Asia during the period of 2000-05 using observed wet deposition data from the Acid Deposition Monitoring Network in East Asia (EANET). Observational trends show a high proportion of NH4+ in the total cations, with a six-year mean proportion of over 20% for continental and inland regions. The concentrations and deposition of NH4+ were higher in western China and Vietnam than in other regions. The annual variations in NH4+ concentration were smooth in most of the regions, except for southern China and Vietnam, where the NH4+ concentrations increased, and western China, where the NH4+ concentrations decreased. The neutralization factors (NFs) of NH4+ indicate that ammonia has a great neutralization capability toward acid rain, including for the regions with low NH4+ concentrations, such as Japan. The NFs were high in summer, with no obvious discrepancies between the northern and southern stations. However, the correlation coefficients between NH4+ concentrations and rain pH values imply that the ammonia neutralization effects on the pH values were distinct only at southern China and southern Japan stations. The neutralization of precipitation by ammonia was estimated by comparing the discrepancies between the observed pH values and the pH values calculated without ammonia consuming the H+ in NH4+. The results demonstrate that ammonia may increase annual mean pH values by 0.4-0.7 in southern China and by 0.15-0.25 in southern Japan.

  9. Numerical modeling of the effect of variation of boundary conditions on vadose zone hydraulic properties

    Directory of Open Access Journals (Sweden)

    Tairone Paiva Leão

    2011-02-01

    Full Text Available An accurate estimation of hydraulic fluxes in the vadose zone is essential for the prediction of water, nutrient and contaminant transport in natural systems. The objective of this study was to simulate the effect of variation of boundary conditions on the estimation of hydraulic properties (i.e. water content, effective unsaturated hydraulic conductivity and hydraulic flux in a one-dimensional unsaturated flow model domain. Unsaturated one-dimensional vertical water flow was simulated in a pure phase clay loam profile and in clay loam interlayered with silt loam distributed according to the third iteration of the Cantor Bar fractal object Simulations were performed using the numerical model Hydrus 1D. The upper and lower pressure heads were varied around average values of -55 cm for the near-saturation range. This resulted in combinations for the upper and lower constant head boundary conditions, respectively, of -50 and -60 cm, -40 and -70 cm, -30 and -80 cm, -20 and -90 cm, and -10 and -100 cm. For the drier range the average head between the upper and lower boundary conditions was set to -550 cm, resulting in the combinations -500 and -600 cm, -400 and -700 cm, -300 and -800 cm, -200 and -900 cm, and -100 and -1,000 cm, for upper and lower boundary conditions, respectively. There was an increase in water contents, fluxes and hydraulic conductivities with the increase in head difference between boundary conditions. Variation in boundary conditions in the pure phase and interlayered one-dimensional profiles caused significant deviations in fluxes, water contents and hydraulic conductivities compared to the simplest case (a head difference between the upper and lower constant head boundaries of 10 cm in the wetter range and 100 cm in the drier range.

  10. The effects of dust temperature and the dust charge variation in a dusty plasma with vortex-like ion distribution

    Institute of Scientific and Technical Information of China (English)

    段文山

    2003-01-01

    By considering both the dust temperature and the dust charge variation in dusty plasma with vortex-like ion distribution, we obtained a modified Korteweg-de Vries equation. It indicates that the effect of dust charge variation can cause the one-dimensional soliton amplitude to become larger, and the dust temperature can cause the soliton amplitude to become larger as well. Moreover, as the dust temperature increases, the soliton amplitude will increase.

  11. The effects of dust temperature and the dust charge variation in a dusty plasma with vortex—like ion distribution

    Institute of Scientific and Technical Information of China (English)

    DuanWen-Shan

    2003-01-01

    By considering both the dust temperature and the dust charge variation in dusty plasma with vortex-like ion distribution, we obtained a modified Korteweg-de Vries equation. It indicates that the effect of dust charge variation can cause the one-dimensional solition amplitude to become larger, and the dust temperature can cause the soliton amplitude to become larger as well. Moreover, as the dust temperature increases, the soliton amplitude will increase.

  12. Development of a new generation of high-resolution anatomical models for medical device evaluation: the Virtual Population 3.0

    Science.gov (United States)

    Gosselin, Marie-Christine; Neufeld, Esra; Moser, Heidi; Huber, Eveline; Farcito, Silvia; Gerber, Livia; Jedensjö, Maria; Hilber, Isabel; Di Gennaro, Fabienne; Lloyd, Bryn; Cherubini, Emilio; Szczerba, Dominik; Kainz, Wolfgang; Kuster, Niels

    2014-09-01

    The Virtual Family computational whole-body anatomical human models were originally developed for electromagnetic (EM) exposure evaluations, in particular to study how absorption of radiofrequency radiation from external sources depends on anatomy. However, the models immediately garnered much broader interest and are now applied by over 300 research groups, many from medical applications research fields. In a first step, the Virtual Family was expanded to the Virtual Population to provide considerably broader population coverage with the inclusion of models of both sexes ranging in age from 5 to 84 years old. Although these models have proven to be invaluable for EM dosimetry, it became evident that significantly enhanced models are needed for reliable effectiveness and safety evaluations of diagnostic and therapeutic applications, including medical implants safety. This paper describes the research and development performed to obtain anatomical models that meet the requirements necessary for medical implant safety assessment applications. These include implementation of quality control procedures, re-segmentation at higher resolution, more-consistent tissue assignments, enhanced surface processing and numerous anatomical refinements. Several tools were developed to enhance the functionality of the models, including discretization tools, posing tools to expand the posture space covered, and multiple morphing tools, e.g., to develop pathological models or variations of existing ones. A comprehensive tissue properties database was compiled to complement the library of models. The results are a set of anatomically independent, accurate, and detailed models with smooth, yet feature-rich and topologically conforming surfaces. The models are therefore suited for the creation of unstructured meshes, and the possible applications of the models are extended to a wider range of solvers and physics. The impact of these improvements is shown for the MRI exposure of an adult

  13. Understanding long-term variations in an elephant piosphere effect to manage impacts.

    Science.gov (United States)

    Landman, Marietjie; Schoeman, David S; Hall-Martin, Anthony J; Kerley, Graham I H

    2012-01-01

    Surface water availability is a key driver of elephant impacts on biological diversity. Thus, understanding the spatio-temporal variations of these impacts in relation to water is critical to their management. However, elephant piosphere effects (i.e. the radial pattern of attenuating impact) are poorly described, with few long-term quantitative studies. Our understanding is further confounded by the complexity of systems with elephant (i.e. fenced, multiple water points, seasonal water availability, varying population densities) that likely limit the use of conceptual models to predict these impacts. Using 31 years of data on shrub structure in the succulent thickets of the Addo Elephant National Park, South Africa, we tested elephant effects at a single water point. Shrub structure showed a clear sigmoid response with distance from water, declining at both the upper and lower limits of sampling. Adjacent to water, this decline caused a roughly 300-m radial expansion of the grass-dominated habitats that replace shrub communities. Despite the clear relationship between shrub structure and ecological functioning in thicket, the extent of elephant effects varied between these features with distance from water. Moreover, these patterns co-varied with other confounding variables (e.g. the location of neighboring water points), which limits our ability to predict such effects in the absence of long-term data. We predict that elephant have the ability to cause severe transformation in succulent thicket habitats with abundant water supply and elevated elephant numbers. However, these piosphere effects are complex, suggesting that a more integrated understanding of elephant impacts on ecological heterogeneity may be required before water availability is used as a tool to manage impacts. We caution against the establishment of water points in novel succulent thicket habitats, and advocate a significant reduction in water provisioning at our study site, albeit with greater

  14. Understanding long-term variations in an elephant piosphere effect to manage impacts.

    Directory of Open Access Journals (Sweden)

    Marietjie Landman

    Full Text Available Surface water availability is a key driver of elephant impacts on biological diversity. Thus, understanding the spatio-temporal variations of these impacts in relation to water is critical to their management. However, elephant piosphere effects (i.e. the radial pattern of attenuating impact are poorly described, with few long-term quantitative studies. Our understanding is further confounded by the complexity of systems with elephant (i.e. fenced, multiple water points, seasonal water availability, varying population densities that likely limit the use of conceptual models to predict these impacts. Using 31 years of data on shrub structure in the succulent thickets of the Addo Elephant National Park, South Africa, we tested elephant effects at a single water point. Shrub structure showed a clear sigmoid response with distance from water, declining at both the upper and lower limits of sampling. Adjacent to water, this decline caused a roughly 300-m radial expansion of the grass-dominated habitats that replace shrub communities. Despite the clear relationship between shrub structure and ecological functioning in thicket, the extent of elephant effects varied between these features with distance from water. Moreover, these patterns co-varied with other confounding variables (e.g. the location of neighboring water points, which limits our ability to predict such effects in the absence of long-term data. We predict that elephant have the ability to cause severe transformation in succulent thicket habitats with abundant water supply and elevated elephant numbers. However, these piosphere effects are complex, suggesting that a more integrated understanding of elephant impacts on ecological heterogeneity may be required before water availability is used as a tool to manage impacts. We caution against the establishment of water points in novel succulent thicket habitats, and advocate a significant reduction in water provisioning at our study site

  15. Untangling natural seascape variation from marine reserve effects using a landscape approach.

    Directory of Open Access Journals (Sweden)

    Brittany E Huntington

    Full Text Available Distinguishing management effects from the inherent variability in a system is a key consideration in assessing reserve efficacy. Here, we demonstrate how seascape heterogeneity, defined as the spatial configuration and composition of coral reef habitats, can mask our ability to discern reserve effects. We then test the application of a landscape approach, utilizing advances in benthic habitat mapping and GIS techniques, to quantify this heterogeneity and alleviate the confounding influence during reserve assessment. Seascape metrics were quantified at multiple spatial scales using a combination of spatial image analysis and in situ surveys at 87 patch reef sites in Glover's Reef Lagoon, Belize, within and outside a marine reserve enforced since 1998. Patch reef sites were then clustered into classes sharing similar seascape attributes using metrics that correlated significantly to observed variations in both fish and coral communities. When the efficacy of the marine reserve was assessed without including landscape attributes, no reserve effects were detected in the diversity and abundance of fish and coral communities, despite 10 years of management protection. However, grouping sites based on landscape attributes revealed significant reserve effects between site classes. Fish had higher total biomass (1.5x and commercially important biomass (1.75x inside the reserve and coral cover was 1.8 times greater inside the reserve, though direction and degree of response varied by seascape class. Our findings show that the application of a landscape classification approach vastly improves our ability to evaluate the efficacy of marine reserves by controlling for confounding effects of seascape heterogeneity and suggests that landscape heterogeneity should be considered in future reserve design.

  16. Effects of seasonal and climate variations on calves' thermal comfort and behaviour

    Science.gov (United States)

    Tripon, Iulian; Cziszter, Ludovic Toma; Bura, Marian; Sossidou, Evangelia N.

    2014-09-01

    The aim of this study was to measure the effect of season and climate variations on thermal comfort and behaviour of 6-month-old dairy calves housed in a semi-opened shelter to develop animal-based indicators for assessing animal thermal comfort. The ultimate purpose was to further exploit the use of those indicators to prevent thermal stress by providing appropriate care to the animals. Measurements were taken for winter and summer seasons. Results showed that season significantly influenced ( P ≤ 0.01) the lying down behaviour of calves by reducing the time spent lying, from 679.9 min in winter to 554.1 min in summer. Moreover, season had a significant influence ( P ≤ 0.01) on feeding behaviour. In detail, the total length of feeding periods was shorter in winter, 442.1 min in comparison to 543.5 min in summer. Time spent drinking increased significantly ( P ≤ 0.001), from 11.9 min in winter to 26.9 min in summer. Furthermore, season had a significant influence ( P ≤ 0.001) on self grooming behaviour which was 5.5 times longer in duration in winter than in summer (1,336 s vs 244 s). It was concluded that calves' thermal comfort is affected by seasonal and climate variations and that this can be assessed by measuring behaviour with animal-based indicators, such as lying down, resting, standing up, feeding, rumination, drinking and self grooming. The indicators developed may be a useful tool to prevent animal thermal stress by providing appropriate housing and handling to calves under seasonal and climate challenge.

  17. Effects of the Observed Meridional Flow Variations since 1996 on the Sun's Polar Fields

    Science.gov (United States)

    Hathaway, David H.; Upton, Lisa

    2013-01-01

    The cause of the low and extended minimum in solar activity between Sunspot Cycles 23 and 24 was the small size of Sunspot Cycle 24 itself - small cycles start late and leave behind low minima. Cycle 24 is small because the polar fields produced during Cycle 23 were substantially weaker than those produced during the previous cycles and those (weak) polar fields are the seeds for the activity of the following cycle. The polar fields are produced by the latitudinal transport of magnetic flux that emerged in low-latitude active regions. The polar fields thus depend upon the details of both the flux emergence and the flux transport. We have measured the flux transport flows (differential rotation, meridional flow, and supergranules) since 1996 and find systematic and substantial variation in the meridional flow alone. Here we present experiments using a Surface Flux Transport Model in which magnetic field data from SOHO/MDI and SDO/HMI are assimilated into the model only at latitudes between 45-degrees north and south of the equator (this assures that the details of the active region flux emergence are well represented). This flux is then transported in both longitude and latitude by the observed flows. In one experiment the meridional flow is given by the time averaged (and north-south symmetric) meridional flow profile. In the second experiment the time-varying and north-south asymmetric meridional flow is used. Differences between the observed polar fields and those produced in these two experiments allow us to ascertain the effects of these meridional flow variations on the Sun s polar fields.

  18. Effect of culture methods on individual variation in the growth of sea cucumber Apostichopus japonicus within a cohort and family

    Science.gov (United States)

    Qiu, Tianlong; Zhang, Libin; Zhang, Tao; Bai, Yucen; Yang, Hongsheng

    2014-07-01

    There is substantial individual variation in the growth rates of sea cucumber Apostichopus japonicus individuals. This necessitates additional work to grade the seed stock and lengthens the production period. We evaluated the influence of three culture methods (free-mixed, isolated-mixed, isolated-alone) on individual variation in growth and assessed the relationship between feeding, energy conversion efficiency, and individual growth variation in individually cultured sea cucumbers. Of the different culture methods, animals grew best when reared in the isolated-mixed treatment (i.e., size classes were held separately), though there was no difference in individual variation in growth between rearing treatment groups. The individual variation in growth was primarily attributed to genetic factors. The difference in food conversion efficiency caused by genetic differences among individuals was thought to be the origin of the variance. The level of individual growth variation may be altered by interactions among individuals and environmental heterogeneity. Our results suggest that, in addition to traditional seed grading, design of a new kind of substrate that changes the spatial distribution of sea cucumbers would effectively enhance growth and reduce individual variation in growth of sea cucumbers in culture.

  19. The effects of variations in dose and method of administration on glucagon like peptide-2 activity in the rat

    DEFF Research Database (Denmark)

    Kaji, Tatsuru; Tanaka, Hiroaki; Holst, Jens Juul;

    2008-01-01

    Glucagon-like peptide-2 (GLP-2) is a potent, intestinal-specific trophic hormone. However, the relationship between the dose and timing of GLP-2 administration and these trophic effects is not clear. We investigated the effects of variations in the dose and timing of GLP-2 administration on its i...

  20. Effects of Variation in Truck Factor on Pavement Performance in Pakistan

    Directory of Open Access Journals (Sweden)

    Rabia Chaudry

    2013-01-01

    Full Text Available Seasonal variation coupled with heavy axle loading is the key factor in rapid road deterioration in Pakistan. The serviceability loss is further accelerated by the fact that truck drivers and owners consider overloading as a profitable practice unaware of the adverse effects of this practice. Weigh-in-motion data from two stations located between two major cities of Pakistan (Peshawar and Rawalpindi on Grand Trunk Road (N-5 were collected and analyzed. Analysis of variance and comparison of actual and designed truck factor were performed to identify the most damaging axle truck type. It was found that axle truck type 3 (single/tandem axle is most damaging among all truck types. The actual truck factor for axle truck type 3 is 6.4 times greater than design truck factor. Regression expressions of different forms were also investigated to determine the relationship between truck factor and gross vehicular weight for the specified truck types. An optimum generalization strategy was used to prevent over-generalization and ensure accuracy. For data analysis, 75% of data was used to develop regression models and remaining 25% was to validate those models. The results show that the polynomial expressions performed best and provide a robust relationship that can be employed by the highway authorities to estimate truck factor from gross vehicular weight with a high degree of confidence. It was also observed that damaging effect of various types of trucks was very severe and quite high.

  1. Effects on Variations in M1 Generation of Durum Wheat (T. durum Thell by Induced Mutagen

    Directory of Open Access Journals (Sweden)

    O. Bilgin

    2005-01-01

    Full Text Available In this research conducted ın Department of Field Crops, Tekirdağ Agricultural Faculty, TrakyaUniversity, the effect of six different gamma ray doses on plant growth in M1 generations derived from twodurum wheat cultivars was investigated.In the experiment, 10 plants in each pot (17 x 40 cm containing 5 kgsoil were grown with three replicates. Total 30 plants for each treatment were used. In M1 generation, numberof leaves, number of roots, seedling height, seedling weight, leaf weight and germination rate were determined.Application of 100-200 gray gamma ray doses did not have any inhibitory effect on investigated characters inseedling growth of M1 generation. On the other hand, 400-500 gray doses significantly inhibited the plantgrowth. 100-200 gray doses did not affect the seed germination rate whereas germination rate decreased with400-500 gray gamma ray applications. At 600 gray dose, only one seed remained viably, rest of them could notsurvive. It was generally observed the highest variations at 300-400 gray gamma doses in M1 plants.

  2. Clinical effect of individualization anatomical reconstruction of anterior cruciate ligament%经关节镜个体化解剖重建前交叉韧带术后临床观察

    Institute of Scientific and Technical Information of China (English)

    黄广振; 黄遂柱; 赵甲军; 侯玉科

    2013-01-01

    Objective To observe the clinical effect of arthroscopic individualization single bundle anterior cruciate ligament (ACL) reconstruction.Methods With the informed consents,60 cases with ACL injury who underwent arthroscopic reconstruction were selected from Henan province people' s hospital from January 2011 to September2011,all of the patients were followed up after ACL reconstructive surgery.To collect the data of knee stability,range of motion,myodynamic recovery,gait analysis,self-induction satisfaction,Lysholm score (0-100 points,higher scores indicated better functionaI recovery of knee joint),Tegner score (0-10 points,higher scores indicated better functionaI recovery of knee joint),and analyse the kinematic data.Results All of the 60 patients had been followed up for 12-18 months,average 16 months.Active range of motion,gait and quadriceps femoris strength can returned to normal in early postoperative.At the end of follow up:Lysholm scores increased from 48.4 ±8.7 to 92.2 ± 2.4 (P < 0.05).Tegner scores increased from 2-4 to 6-8 (P < 0.05).Conclusions Individualization anatomic ACL reconstruction seemed to best match the native femoral and tibial ACL footprint,and the function of knee joint can be obviously improved in ACL reconstruction.%目的 探讨关节镜下个体化单束解剖重建膝关节前交叉韧带(ACL)的临床疗效.方法 选择2011年1月至9月行关节镜下个体化单束解剖重建ACL手术患者60例,术后2、3、6、12、18个月定期随访.对膝关节稳定性、活动度、股四头肌肌力、步态、患者自感满意度、Lysholm评分、Tegner评分等数据收集,对其数据进行客观评价.结果 60例患者随访12 ~18个月,平均16个月.术后膝关节活动度、肌力、步态均可早期恢复正常.随访结束时Lysholm评分由术前的(48.4±8.7)分提高至(92.2±2.4)分,Tegner评分由术前的2~4分提高至6~8分,膝关节运动评分显著高于术前,差异有统计学意义(P<0.05).

  3. 钾对不同钾效率棉花基因型叶片解剖结构的影响%Effects of potassium fertilization on leaf anatomical structures of different cotton genotypes

    Institute of Scientific and Technical Information of China (English)

    姜存仓; 郝艳淑; 王晓丽; 夏颖; 王运华

    2011-01-01

    以钾高效高潜基因型HG103和低效低潜基因型LG122为材料,在盆栽条件下研究了钾对不同棉花基因型叶片解剖结构的影响。结果表明,花铃期施钾条件下HG103上部叶主叶脉的上、下表皮细胞排列较LG122紧密和整齐,而下部叶片则相反;缺钾后HG103上部叶主叶脉比LG122发育得好;HG103叶脉维管束木质部具有较多导管数,利于养分和水分等的运输,而LG122木质部导管数相对较少;HG103上部叶叶脉的韧皮部比LG122较为发达,利于光合产物运输。花铃期施钾条件下HG103上部叶的叶肉细胞结构与LG122差别不大,下部叶的栅栏组织则没有LG122排列的整齐。缺钾时,HG103上部叶叶肉的上表皮细胞比LG122排列的较为整齐,栅栏组织和海绵组织形状较规则;而下部叶LG122栅栏组织和海绵组织比HG103分化得好。%To study the effects of potassium(K) on leaf anatomical structures of different cotton genotypes,a pot experiment was conducted at Huazhong Agricultural University.There were two cotton genotypes(HG103,and LG122),two K application levels(0 and 0.4 g/kg soil).The HG103(high K efficiency genotype) and LG122(low K efficiency genotype) were selected from 86 cotton cultivars(Gossypium hirsutum L.).The results show that the upper leaves main veins of the upper or the lower epidermis cells of HG103 are more tight and neat than those of LG122 when adding K,while the main veins of lower leaves are opposite.The upper leaf main veins of HG103 are better than those of LG122 under the no K level.HG103 has lots of vascular xylem vein catheters which benefits nutrients and moisture transportion,while LG122 has small number of xylem conduits.The phloem veins of the upper part of HG103 are better than those of LG122,which could help HG103 transport much of photosynthetic products.The structures of upper leaf mesophyll cells of HG103 and LG122 are not very different when applying K,but lower leaf

  4. Probabilistic anatomical labeling of brain structures using statistical probabilistic anatomical maps

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Su; Lee, Dong Soo; Lee, Byung Il; Lee, Jae Sung; Shin, Hee Won; Chung, June Key; Lee, Myung Chul [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2002-12-01

    The use of statistical parametric mapping (SPM) program has increased for the analysis of brain PET and SPECT images. Montreal neurological institute (MNI) coordinate is used in SPM program as a standard anatomical framework. While the most researchers look up Talairach atlas to report the localization of the activations detected in SPM program, there is significant disparity between MNI templates and Talairach atlas. That disparity between Talairach and MNI coordinates makes the interpretation of SPM result time consuming, subjective and inaccurate. The purpose of this study was to develop a program to provide objective anatomical information of each x-y-z position in ICBM coordinate. Program was designed to provide the anatomical information for the given x-y-z position in MNI coordinate based on the statistical probabilistic anatomical map (SPAM) images of ICBM. When x-y-z position was given to the program, names of the anatomical structures with non-zero probability and the probabilities that the given position belongs to the structures were tabulated. The program was coded using IDL and JAVA language for the easy transplantation to any operating system or platform. Utility of this program was shown by comparing the results of this program to those of SPM program. Preliminary validation study was performed by applying this program to the analysis of PET brain activation study of human memory in which the anatomical information on the activated areas are previously known. Real time retrieval of probabilistic information with 1 mm spatial resolution was archived using the programs. Validation study showed the relevance of this program: probability that the activated area for memory belonged to hippocampal formation was more than 80%. These programs will be useful for the result interpretation of the image analysis performed on MNI coordinate, as done in SPM program.

  5. Effects of ionic strength on the binding of phenanthrene and pyrene to humic substances: three-stage variation model.

    Science.gov (United States)

    Lee, Chon-Lin; Kuo, Li-Jung; Wang, Huei-Ling; Hsieh, Ping-Chieh

    2003-10-01

    This study compared the effects of ionic strength on the binding constants (K(doc)) of selected polycyclic aromatic hydrocarbons (PAHs) (phenanthrene and pyrene) and a terrestrial humic acid (Leonardite Humic Acid) in different electrolyte solutions (KCl, KBr, MgCl(2) and MgSO(4)). Distinct trends were found in K(doc) variation depending upon the range of ionic strength resulting from added electrolytes. These trends demonstrated similar shapes for all the systems studied, while degree of variation increased with hydrophobicity of the PAHs. Furthermore, different types of electrolytes had different effects on the interactions between humic acid (HA) and the PAHs. These differences were primarily caused by types of cation, not anion. To describe the complicated effects of ionic strength on K(doc), we developed a three-stage variation model that encompasses increasing and decreasing trends and plateaus in K(doc) associated with ionic strength, as well as the mechanisms behind these trends, including the variation of HA structure configuration, HA aggregation and the salting-out effect. This model illustrated the importance of sufficient experimental data when interpreting the influence of ionic strength on the trends in K(doc) variation. PMID:12946908

  6. Anatomical and Radiological Aspects of the Supratrochlear Foramen in Brazilians

    Science.gov (United States)

    Gutfiten-Schlesinger, Gabriel; Leite, Túlio FO; Pires, Lucas AS; Silva, Julio G.

    2016-01-01

    Introduction The supratrochlear foramen is an anatomic variation of great clinical and anthropologic interest. Although many studies addressed this subject in different ethnic groups, there are no studies regarding Brazilians. Aim To verify the incidence and morphometric measures of the supratrochlear foramen in Brazilian humeri. Materials and Methods A total of 330 dry humeri were analysed and divided in three groups: bones presenting the supratrochlear foramen (Group 1), bones displaying a translucent foramen (Group 2) and humeri without the foramen (Group 3). The aperture was measured with a digital vernier caliper. Radiographic pictures with different incidences were taken. Results Our analysis showed that 22.5% of humeri belonged in Group 1, 41.2% in Group 2, and 36.3% in Group 3. The mean vertical diameter and the mean horizontal diameter of the supratrochlear foramen on the left side were 2.779±2.050 mm and 2.332±1.23 mm, respectively. The mean vertical diameter and the mean horizontal diameter of the foramen on the right side were 2.778±2.197 mm, and 2.365±1.396 mm, respectively. The student’s t-test showed that there was no significant difference regarding the size of the foramen between both sides. The best X-ray machine setup was 50 kilo voltage and 0.08 milliamperage per second, associated with a slight increase in the distance of the x-ray tube. Conclusion The aperture seems to be the key point during the pre-operative planning of intramedullary fixation, since it has direct relation to the size of the intramedullary canal, thus, being an entity of clinical, anatomical, anthropological, radiological, and surgical interest. PMID:27790415

  7. Assessing intraspecific variation in effective dispersal along an altitudinal gradient: a test in two Mediterranean high-mountain plants.

    Directory of Open Access Journals (Sweden)

    Carlos Lara-Romero

    Full Text Available BACKGROUND: Plant recruitment depends among other factors on environmental conditions and their variation at different spatial scales. Characterizing dispersal in contrasting environments may thus be necessary to understand natural intraspecific variation in the processes underlying recruitment. Silene ciliata and Armeria caespitosa are two representative species of cryophilic pastures above the tree line in Mediterranean high mountains. No explicit estimations of dispersal kernels have been made so far for these or other high-mountain plants. Such data could help to predict their dispersal and recruitment patterns in a context of changing environments under ongoing global warming. METHODS: We used an inverse modelling approach to analyse effective seed dispersal patterns in five populations of both Silene ciliata and Armeria caespitosa along an altitudinal gradient in Sierra de Guadarrama (Madrid, Spain. We considered four commonly employed two-dimensional seedling dispersal kernels exponential-power, 2Dt, WALD and log-normal. KEY RESULTS: No single kernel function provided the best fit across all populations, although estimated mean dispersal distances were short (<1 m in all cases. S. ciliata did not exhibit significant among-population variation in mean dispersal distance, whereas significant differences in mean dispersal distance were found in A. caespitosa. Both S. ciliata and A. caespitosa exhibited among-population variation in the fecundity parameter and lacked significant variation in kernel shape. CONCLUSIONS: This study illustrates the complexity of intraspecific variation in the processes underlying recruitment, showing that effective dispersal kernels can remain relatively invariant across populations within particular species, even if there are strong variations in demographic structure and/or physical environment among populations, while the invariant dispersal assumption may not hold for other species in the same environment

  8. [Sigismund Laskowski and his anatomical preparations technique].

    Science.gov (United States)

    Gryglewski, Ryszard W

    2015-01-01

    Fixation of the entire bodies or individual organs, and later as well tissues and cellular structures, was and still is often a challenge for anatomists and histologists. Technique that combines extensive knowledge of natural sciences, as well as technical skills, was by those best researchers as Frederik Ruysch, brought to perfection. Preparations, if done with care and talent, are really propelling progress in anatomical studies and determining the quality of education for medical students and young physicians. And as it is true for many of today's medical disciplines and natural sciences, the nineteenth century was in many ways a breaking point for preparatory techniques in the realm of anatomy and histology. Among those who have achieved success, earning notoriety during their lifetime and often going into the annals of European most distinguished scholars were some Polish names: Louis Maurice Hirschfeld, whose preparations of the nervous system earned him well-deserved, international fame, Louis Charles Teichmann, who was the very first so precisely describing the lymphatic system and a creator of unique injection mass, Henry Kadyi, known for his outstanding preparations, especially of vascular system. Henry Frederick Hoyer sen., who was one of the first to use formalin regularly for accurate microscopic preparations, is seen by many as the founder of the Polish histology. In this group of innovators and precursors of modern preparation techniques place should be reserved for Zygmunt (Sigismund) Laskowski, Polish patriot, fighting in January Uprising, later an immigrant, a professor at the university sequentially Paris and Geneva. Acclaimed author of anatomical tables and certainly creator of one of the groundbreaking techniques in anatomical preparations. Based after many years of research on the simple glycerine-phenol mixture achieved excellent results both in fixation of entire bodies and organs or tissues. Quality of those preparations was as high and

  9. Tennis elbow. Anatomical, epidemiological and therapeutic aspects.

    Science.gov (United States)

    Verhaar, J A

    1994-10-01

    Five studies of tennis elbow are presented. Epidemiological studies showed an incidence of tennis elbow between 1 and 2%. The prevalence of tennis elbow in women between 40 and 50 years of age was 10%. Half of the patients with tennis elbow seek medical attention. Local corticosteroid injections were superior to the physiotherapy regime of Cyriax. Release of the common forearm extensor origin resulted in 70% excellent or good results one year after operation and 89% at five years. Anatomical investigations and nerve conduction studies of the Radial Tunnel Syndrome supported the hypothesis that the Lateral Cubital Force Transmission System is involved in the pathogenesis of tennis elbow.

  10. Constitutional and Anatomical Characteristics of Mature Women

    Institute of Scientific and Technical Information of China (English)

    Vladimir NNikolenko; DmitryBNikityuk; SvetlanaVKlochkova; AnastasiaABahmet

    2015-01-01

    Objective To identify the constitutional and anatomical peculiarities of constitution of women of mature age.Methods There was completed comprehensive anthropometric and bio-electrical survey of 651 mature women ( relative norm) living in the Moscow region .Results The quantitative distribution of women by somatotypological affiliation was revealed;anthropometric and body component composition in representatives of different somatotypes were defined .Conclusion Thus, the performed study revealed and quantiely character-ised the distribution of women according to their constitutional types in the studied population of mature age women living in Moscow region under the relative norm conditions .

  11. 40 CFR 53.56 - Test for effect of variations in ambient pressure.

    Science.gov (United States)

    2010-07-01

    ... coefficient of variation of the discrete measurements as follows: Equation 19 ER18jy97.081 (ii) To successfully pass this test, the calculated coefficient of variation for the certified flow rates must not... test run. (4) Flow rate CV measurement accuracy. (i) Using the flow rate coefficient of...

  12. Indexing Effects of Copy Number Variation on Genes Involved in Developmental Delay.

    Science.gov (United States)

    Uddin, Mohammed; Pellecchia, Giovanna; Thiruvahindrapuram, Bhooma; D'Abate, Lia; Merico, Daniele; Chan, Ada; Zarrei, Mehdi; Tammimies, Kristiina; Walker, Susan; Gazzellone, Matthew J; Nalpathamkalam, Thomas; Yuen, Ryan K C; Devriendt, Koenraad; Mathonnet, Géraldine; Lemyre, Emmanuelle; Nizard, Sonia; Shago, Mary; Joseph-George, Ann M; Noor, Abdul; Carter, Melissa T; Yoon, Grace; Kannu, Peter; Tihy, Frédérique; Thorland, Erik C; Marshall, Christian R; Buchanan, Janet A; Speevak, Marsha; Stavropoulos, Dimitri J; Scherer, Stephen W

    2016-01-01

    A challenge in clinical genomics is to predict whether copy number variation (CNV) affecting a gene or multiple genes will manifest as disease. Increasing recognition of gene dosage effects in neurodevelopmental disorders prompted us to develop a computational approach based on critical-exon (highly expressed in brain, highly conserved) examination for potential etiologic effects. Using a large CNV dataset, our updated analyses revealed significant (P < 1.64 × 10(-15)) enrichment of critical-exons within rare CNVs in cases compared to controls. Separately, we used a weighted gene co-expression network analysis (WGCNA) to construct an unbiased protein module from prenatal and adult tissues and found it significantly enriched for critical exons in prenatal (P < 1.15 × 10(-50), OR = 2.11) and adult (P < 6.03 × 10(-18), OR = 1.55) tissues. WGCNA yielded 1,206 proteins for which we prioritized the corresponding genes as likely to have a role in neurodevelopmental disorders. We compared the gene lists obtained from critical-exon and WGCNA analysis and found 438 candidate genes associated with CNVs annotated as pathogenic, or as variants of uncertain significance (VOUS), from among 10,619 developmental delay cases. We identified genes containing CNVs previously considered to be VOUS to be new candidate genes for neurodevelopmental disorders (GIT1, MVB12B and PPP1R9A) demonstrating the utility of this strategy to index the clinical effects of CNVs. PMID:27363808

  13. Physico-chemical properties and cytotoxic effects of sugar-based surfactants: Impact of structural variations.

    Science.gov (United States)

    Lu, Biao; Vayssade, Muriel; Miao, Yong; Chagnault, Vincent; Grand, Eric; Wadouachi, Anne; Postel, Denis; Drelich, Audrey; Egles, Christophe; Pezron, Isabelle

    2016-09-01

    Surfactants derived from the biorefinery process can present interesting surface-active properties, low cytotoxicity, high biocompatibility and biodegradability. They are therefore considered as potential sustainable substitutes to currently used petroleum-based surfactants. To better understand and anticipate their performances, structure-property relationships need to be carefully investigated. For this reason, we applied a multidisciplinary approach to systematically explore the effect of subtle structural variations on both physico-chemical properties and biological effects. Four sugar-based surfactants, each with an eight carbon alkyl chain bound to a glucose or maltose head group by an amide linkage, were synthesized and evaluated together along with two commercially available standard surfactants. Physico-chemical properties including solubility, Krafft point, surface-tension lowering and critical micellar concentration (CMC) in water and biological medium were explored. Cytotoxicity evaluation by measuring proliferation index and metabolic activity against dermal fibroblasts showed that all surfactants studied may induce cell death at low concentrations (below their CMC). Results revealed significant differences in both physico-chemical properties and cytotoxic effects depending on molecule structural features, such as the position of the linkage on the sugar head-group, or the orientation of the amide linkage. Furthermore, the cytotoxic response increased with the reduction of surfactant CMC. This study underscores the relevance of a methodical and multidisciplinary approach that enables the consideration of surfactant solution properties when applied to biological materials. Overall, our results will contribute to a better understanding of the concomitant impact of surfactant structure at physico-chemical and biological levels. PMID:27137806

  14. Aerobic fitness does not modify the effect of FTO variation on body composition traits.

    Directory of Open Access Journals (Sweden)

    Antti Huuskonen

    Full Text Available PURPOSE: Poor physical fitness and obesity are risk factors for all cause morbidity and mortality. We aimed to clarify whether common genetic variants of key energy intake determinants in leptin (LEP, leptin receptor (LEPR, and fat mass and obesity-associated (FTO are associated with aerobic and neuromuscular performance, and whether aerobic fitness can alter the effect of these genotypes on body composition. METHODS: 846 healthy Finnish males of Caucasian origin were genotyped for FTO (rs8050136, LEP (rs7799039 and LEPR (rs8179183 and rs1137101 single nucleotide polymorphisms (SNPs, and studied for associations with maximal oxygen consumption, body fat percent, serum leptin levels, waist circumference and maximal force of leg extensor muscles. RESULTS: Genotype AA of the FTO SNP rs8050136 associated with higher BMI and greater waist circumference compared to the genotype CC. In general linear model, no significant interaction for FTO genotype-relative VO(2max (mL·kg(-1·min(-1 or FTO genotype-absolute VO(2max (L·min(-1 on BMI or waist circumference was found. Main effects of aerobic performance on body composition traits were significant (p<0.001. Logistic regression modelling found no significant interaction between aerobic fitness and FTO genotype. LEP SNP rs7799039, LEPR SNPs rs8179183 and rs1137101 did not associate with any of the measured variables, and no significant interactions of LEP or LEPR genotype with aerobic fitness were observed. In addition, none of the studied SNPs associated with aerobic or neuromuscular performance. CONCLUSIONS: Aerobic fitness may not modify the effect of FTO variation on body composition traits. However, relative aerobic capacity associates with lower BMI and waist circumference regardless of the FTO genotype. FTO, LEP and LEPR genotypes unlikely associate with physical performance.

  15. Effects of variation in food resources on foraging habitat use by wintering Hooded Cranes (Grus monacha)

    Institute of Scientific and Technical Information of China (English)

    Meng Zheng; Lizhi Zhou; Niannian Zhao; Wenbin Xu

    2015-01-01

    Background:The ideal habitat use of waterbirds can be considered to be fixed, but current habitat use depends on environmental conditions, especially those of food characteristics, considered crucial to their use of habitats. Understanding how waterbirds respond to variation in food availability at degraded wetland sites and change their habitat use patterns over spatial and temporal scales should direct future conservation planning. The objectives of this study were to identify these spatial-temporal foraging habitat use patterns of Hooded Cranes (Grus monacha) and their relationship with food characteristics in the severely degraded wetlands of the Shengjin and Caizi lakes along with the Yangtze River floodplain. Methods:We investigated the changes in food characteristics, relative abundance and density of Hooded Cranes in various habitat types across three winter periods from November 2012 to April 2013. We examined the effect of these winter periods and habitat types on the pattern of use by the cranes and explored the relationship between these patterns and food characteristics using linear regression. Results:The food characteristics and habitat use clearly changed over spatial-temporal scales. In the early and mid-winter periods, the most abundant, accessible and frequented food resources were found in paddy fields, while in the late period the more abundant food were available in meadows, which then replaced the paddy fields. There were fewer effects of winter periods, habitat types and their interactions on habitat use patterns except for the effect of habitat types on the relative abundance, determined as a function of food abundance, but independent of food depth and sediment permeability. Conclusions:In response to the degradation and loss of lake wetlands, the cranes shifted their habitat use patterns by making tradeoffs between food abundance and accessibility over spatial-temporal scales that facilitated their survival in the mosaic of these lake

  16. Heat shock protein 101 effects in A. thaliana: genetic variation, fitness and pleiotropy in controlled temperature conditions

    OpenAIRE

    TONSOR, S. J.; Scott, C; BOUMAZA, I.; LISS, T. R.; BRODSKY, J. L.; Vierling, E

    2008-01-01

    The Hsp100/ClpB heat shock protein family is ancient and required for high temperature survival, but natural variation in expression and its phenotypic effects is unexplored in plants. In controlled environment experiments, we examined the effects of variation in the Arabidopsis cytosolic AtHsp101 (hereafter Hsp101). Ten wild-collected ecotypes differed in Hsp101 expression responses across a 22 to 40 °C gradient. Genotypes from low latitudes expressed the least Hsp101. We tested fitness and ...

  17. Carbazole based electrochromic polymers with benzoazole units: Effect of heteroatom variation on electrochromic performance

    Directory of Open Access Journals (Sweden)

    C. Doyranli

    2016-09-01

    Full Text Available A series of carbazole-based polymers were synthesized via Suzuki polymerization between N-(2-ethylhexylcarbazole-3,6-bis(ethyleneboronate (Cbz and dibromobenzazole unit. Three different polymers, PCBN, PCBS and PCBSe were obtained from 4,7-dibromo-2-hexyl-2H-benzotriazole (BN, 4,7-dibromo-2,1,3-benzothiadiazole- (BS and 4,7-dibromo-2,1,3-benzoselenadiazole (BSe, respectively. It is observed that, the variation of heteroatoms (N,S and Se on the benzazole unit have most important effect on electro-optic properties of the PCBX polymers. Neutral state color of the polymer films and their electrochromic performances are also influenced. Among the synthesized polymers, the PCBS bearing 2,1,3-benzothiadiazole as acceptor units has a broad absorption and 50% of ΔT in the near-IR regime at the oxidized state. This property of PCBS is a great advantage for near-IR electrochromic applications.

  18. Structure of Ground state Wave Functions for the Fractional Quantum Hall Effect: A Variational Approach

    Science.gov (United States)

    Mukherjee, Sutirtha; Mandal, Sudhansu

    The internal structure and topology of the ground states for fractional quantum Hall effect (FQHE) are determined by the relative angular momenta between all the possible pairs of electrons. Laughlin wave function is the only known microscopic wave function for which these relative angular momenta are homogeneous (same) for any pair of electrons and depend solely on the filling factor. Without invoking any microscopic theory, considering only the relationship between number of flux quanta and particles in spherical geometry, and allowing the possibility of inhomogeneous (different) relative angular momenta between any two electrons, we develop a general method for determining a closed-form ground state wave function for any incompressible FQHE state. Our procedure provides variationally obtained very accurate wave functions, yet having simpler structure compared to any other known complex microscopic wave functions for the FQHE states. This method, thus, has potential in predicting a very accurate ground state wave function for the puzzling states such as the state at filling fraction 5/2. We acknowledge support from Department of Science and Technology, India.

  19. Thermospheric density variations: Observability using precision satellite orbits and effects on orbit propagation

    Science.gov (United States)

    Lechtenberg, Travis; McLaughlin, Craig A.; Locke, Travis; Krishna, Dhaval Mysore

    2013-01-01

    paper examines atmospheric density estimated using precision orbit ephemerides (POE) from the CHAMP and GRACE satellites during short periods of greater atmospheric density variability. The results of the calibration of CHAMP densities derived using POEs with those derived using accelerometers are examined for three different types of density perturbations, [traveling atmospheric disturbances (TADs), geomagnetic cusp phenomena, and midnight density maxima] in order to determine the temporal resolution of POE solutions. In addition, the densities are compared to High-Accuracy Satellite Drag Model (HASDM) densities to compare temporal resolution for both types of corrections. The resolution for these models of thermospheric density was found to be inadequate to sufficiently characterize the short-term density variations examined here. Also examined in this paper is the effect of differing density estimation schemes by propagating an initial orbit state forward in time and examining induced errors. The propagated POE-derived densities incurred errors of a smaller magnitude than the empirical models and errors on the same scale or better than those incurred using the HASDM model.

  20. Variation of Thermochromic Glazing Systems Transition Temperature, Hysteresis Gradient and Width Effect on Energy Efficiency

    Directory of Open Access Journals (Sweden)

    Michael E. A. Warwick

    2016-06-01

    Full Text Available Due to increasing pressure to reduce the energy demand in buildings, thermochromic thin film based glazing has become a recognized potential solution due to the intrinsic ability to modulate the solar heat gain of a window as a function of the materials temperature. These “intelligent” glazings have been investigated for several years, and it has been found that, through variation of synthetic route, the thermochromic properties (transition temperature, hysteresis gradient and width can be altered; however, less attention has been applied to how such alterations affect the overall energy savings attributed to the materials. In this study the building simulation software EnergyPlus TM has been used to model a series of idealized thermochromic spectra in a series of different environments to evaluate their energy saving potential against both clear glass systems and industry standards. The idealized spectra are used to see what effect each of the materials thermochromic properties and therefore elucidate which are the most important with respect to the energy saving properties. It was found that the best thermochromic materials were those with a narrow sharp hysteresis and a low transition temperature and result in an increase in energy saving between 30%–45% across the different environments compared to clear glass systems.

  1. Phase variation of Opa proteins of Neisseria meningitidis and the effects of bacterial transformation

    Indian Academy of Sciences (India)

    Manish Sadarangani; J Claire Hoe; Katherine Makepeace; Peter Van Der Ley; Andrew J Pollard

    2016-03-01

    Opa proteins are major proteins involved in meningococcal colonization of the nasopharynx and immune interactions. Opa proteins undergo phase variation (PV) due to the presence of the 5′-CTCTT-3′ coding repeat (CR) sequence. The dynamics of PV of meningococcal Opa proteins is unknown. Opa PV, including the effect of transformation on PV, was assessed using a panel of Opa-deficient strains of Neisseria meningitidis. Analysis of Opa expression from UK disease-causing isolates was undertaken. Different opagenes demonstrated variable rates of PV, between 6.4 ×10–4 and 6.9 ×10–3 per cell per generation. opa genes with a longer CR tract had a higher rate of PV (r2=0.77, p=0.1212). Bacterial transformation resulted in a 180-fold increase in PV rate. The majority of opagenes in UK disease isolates (315/463, 68.0%) were in the ‘on’ phase, suggesting the importance of Opa proteins during invasive disease. These data provide valuable information for the first time regarding meningococcal Opa PV. The presence of Opa PV in meningococcal populations and high expression of Opa among invasive strains likely indicates the importance of this protein in bacterial colonization in the human nasopharynx. These findings have potential implications for development of vaccines derived from meningococcal outer membranes.

  2. English fluency of the US immigrants: Assimilation effects, cohort variations, and periodical changes.

    Science.gov (United States)

    Xi, Juan

    2013-07-01

    Using 1% Public-Use Microdata Samples (PUMSs) of the 1980, 1990, and 2000 census and the 2010 American Community Survey (ACS), this study evaluates three simultaneous longitudinal trends in immigrants' English fluency: the assimilation process, variations across arrival cohorts, and periodical changes. The key findings include that the declining initial English fluency among new immigrants reported in a previous study based on 1980 and 1990 data (Carliner, 2000) was reversed in the 1990s and 2000s. Immigrants who arrived during the 2000s have the highest level of English fluency at the year of entry among all cohorts. Immigrants are assimilating. However, changes in social and linguistic environment in the US during the past two decades have suppressed the advancement of immigrants. The decline in the average English attainment from the 1980s to the 1990s reported in a previous study (Pitkin and Myers, 2011) was found to extend to the 2000s. Using new census data, this study updated the current knowledge on immigrants' English fluency by revealing a never documented upward trend among recent immigrants and suppressive period effects from 1990 to 2010. PMID:23721677

  3. Effective depth-of-penetration range due to hardness variation for different lots of nominally identical target material

    Directory of Open Access Journals (Sweden)

    Patrick Frueh

    2016-04-01

    A linear regression analysis of penetration vs. hardness shows that a target hardness increase within the given range of 280–330 BHN may result in a reduction of penetration depth of about 5.8 mm at constant velocity. This is equal to a change of −12% at an impact velocity of 1250 m/s. A multiple linear regression analysis included also the influence of yaw angle and impact velocity. It shows that small yaw angles and slight variations of impact velocities provide a smaller variation of the semi-infinite penetration depths than a variation of target hardness within a typical specification span of 50 BHN. For such a span a change in penetration of approximately −4.8 mm due to hardness variation is found, whereas 1° of yaw angle or −10 m/s of velocity variation gives a change of about −1.0 mm respectively −0.9 mm. For the given example, the overwhelming part of the variation is to be attributed to hardness effects – 4.8 mm out of 5.8 mm (83%. For nominally identical target material the target hardness thus influences the ballistic test results more severely than the typical scatter in impact conditions.

  4. Isolated Male Epispadias: Anatomic Functional Restoration Is the Primary Goal

    Science.gov (United States)

    Bruneel, Elke; Ploumidis, Achilles; Van Laecke, Erik; Hoebeke, Piet

    2016-01-01

    Background. Isolated male epispadias (IME) is a rare congenital penile malformation, as often part of bladder-exstrophy-epispadias complex (BEEC). In its isolated presentation, it consists in a defect of the dorsal aspect of the penis, leaving the urethral plate open. Occurrence of urinary incontinence is related to the degree of dorsal displacement of the meatus and the underlying underdevelopment of the urethral sphincter. The technique for primary IME reconstruction, based on anatomic restoration of the urethra and bladder neck, is here illustrated. Patients and Methods. A retrospective database was created with patients who underwent primary IME repair between June 1998 and February 2014. Intraoperative variables, postoperative complications, and outcomes were assessed. A descriptive statistical analysis was performed. Results and Limitations. Eight patients underwent primary repair, with penopubic epispadias (PPE) in 3, penile epispadias (PE) in 2, and glandular epispadias (GE) in 3. Median age at surgery was 13.0 months [7–47]; median follow-up was 52 months [9–120]. Complications requiring further surgery were reported in two patients, while further esthetic surgeries were required in 4 patients. Conclusion. Anatomical restoration in primary IME is safe and effective, with acceptable results given the initial pathology. PMID:27722172

  5. [Osteochondrodysplasias. Prenatal diagnosis and pathological-anatomic findings].

    Science.gov (United States)

    Tennstedt, C; Bartho, S; Bollmann, R; Schwenke, A; Nitz, I; Rothe, K

    1993-03-01

    Prenatal sonographic investigations were applied for malformations to 7,194 foetuses, between October 1985 and April 1992, with 28 cases of osteochondrodysplasia (OCD) and one case of dysostosis being dissected. Included were 20 cases of lethal osteochondrodysplasia, among them two cases of lethal hypophosphatasia, five cases of thanatophoric dysplasia, one case each of Type II shortrib (polydactyly) syndrome (VERMA-NAUMOFF) and metatropic dysplasia, three cases of campomelic dysplasia and eight cases of Type II A imperfect osteogenesis. Also observed were eight cases of nonlethal OCD, among them three cases of diastrophic dysplasia and five of achondroplasia. Dysostosis was recorded from one case and was diagnosed as Type V acrocephalosyndactyly (Pfeiffer). Identification of a specific OCD proved to be difficult in the second or third trimenon. Hence, the form of OCD was prenatally diagnosed only in ten of all cases investigated. Tentative diagnosis was first established from the postmortem radiograph. Additional malformations and other abnormalities then were detected by complementary pathologico-anatomic processing of findings. The final diagnosis was derived from radiological, pathologico-anatomic and histological findings. Diagnosis of this constitutional osteopathy is quite difficult and calls for interdisciplinary cooperation between gynaecologists, neonatologists, paediatric surgeons, radiologists, geneticists and pathologists. More effective counselling of affected families is the major purpose of all the efforts involved. PMID:8499423

  6. 解剖钢板治疗65例肩关节脱位合并肱骨大结节骨折效果分析%The effect analysis on anatomic plate for 65 cases with shoulder joint dislocation and humeral grea-ter tubercle fracture

    Institute of Scientific and Technical Information of China (English)

    夏卫民

    2016-01-01

    Objective:To analyze and explore the clinical effect of anatomic plate for shoulder joint dislocation with hu-meral greater tubercle fracture. Methods:Sixty - five cases with shoulder joint dislocation and humeral greater tubercle fracture were selected and treatment by anatomic plate. For 3 ~ 4 weeks of rehabilitation,and a 6 - month follow - up for all patients. To evaluate and analyze the clinical treatment effect. Results:Plan and dysfunction is meliorative,range of motion,anatomical re-duction return to normal. 45 cases in 65 cases of patient are better,11 patients are good,the total rate is 86. 15% . Conclusion:The effect of anatomic plate for shoulder joint dislocation and humeral greater tubercle fracture was significant.%目的:分析和探讨解剖钢板治疗肩关节脱位合并肱骨大结节骨折的临床治疗效果。方法:应用解剖钢板治疗65例肩关节脱位合并肱骨大结节骨折患者。术后进行为期3~4周的康复训练,随访6个月。评价分析临床治疗效果。结果:解剖钢板治疗法临床疗效显著,疼痛、功能障碍、肩关节活动范围、解剖复位均恢复正常。65例患者中,优45例,良11例,总优良率为86.15%。结论:解剖钢板治疗肩关节脱位合并肱骨大结节骨折的临床治疗效果显著,具有一定的临床实用价值。

  7. A NUMERICAL SIMULATION OF THE EFFECT ON CHINESE REGIONAL CLIMATE DUE TO SEASONAL VARIATION OF LAND SURFACE PARAMETERS (PART II)

    Institute of Scientific and Technical Information of China (English)

    孙健; 李维亮; 周秀骥

    2001-01-01

    The effect on climate due to seasonal variation of vegetation and roughness length was simulated in Part I of this essay. In Part II, the individual effect of albedo and the joint effect of all those factors (vegetation, roughness length and albedo) were calculated by numerical sensitivity experiments. The results showed that: (1) There is no significant effect on precipitation if the albedo of 4 seasons is used to replace the CRCM's climate average data, but the effect on land surface temperature can be seen clearly. And the effect also can be seen in adjacent regions. (2) If all these three factors are used to replace the CRCM's climate average data at the same time, the effect on precipitation is significant, the most variation value is 300 mm. And the effect on temperature is similar to what we can see if only one of these factors in CRCM is replaced by monthly or seasonal data. (3) Seasonal variation of land surface parameters has important effect not only on regional climate, but also on global environment.

  8. Effects of small variations of speed of sound in optoacoustic tomographic imaging

    International Nuclear Information System (INIS)

    Purpose: Speed of sound difference in the imaged object and surrounding coupling medium may reduce the resolution and overall quality of optoacoustic tomographic reconstructions obtained by assuming a uniform acoustic medium. In this work, the authors investigate the effects of acoustic heterogeneities and discuss potential benefits of accounting for those during the reconstruction procedure. Methods: The time shift of optoacoustic signals in an acoustically heterogeneous medium is studied theoretically by comparing different continuous and discrete wave propagation models. A modification of filtered back-projection reconstruction is subsequently implemented by considering a straight acoustic rays model for ultrasound propagation. The results obtained with this reconstruction procedure are compared numerically and experimentally to those obtained assuming a heuristically fitted uniform speed of sound in both full-view and limited-view optoacoustic tomography scenarios. Results: The theoretical analysis showcases that the errors in the time-of-flight of the signals predicted by considering the straight acoustic rays model tend to be generally small. When using this model for reconstructing simulated data, the resulting images accurately represent the theoretical ones. On the other hand, significant deviations in the location of the absorbing structures are found when using a uniform speed of sound assumption. The experimental results obtained with tissue-mimicking phantoms and a mouse postmortem are found to be consistent with the numerical simulations. Conclusions: Accurate analysis of effects of small speed of sound variations demonstrates that accounting for differences in the speed of sound allows improving optoacoustic reconstruction results in realistic imaging scenarios involving acoustic heterogeneities in tissues and surrounding media

  9. Germline Genetic Variation in an Organic Anion Transporter Polypeptide Associated With Methotrexate Pharmacokinetics and Clinical Effects

    Science.gov (United States)

    Treviño, Lisa R.; Shimasaki, Noriko; Yang, Wenjian; Panetta, John C.; Cheng, Cheng; Pei, Deqing; Chan, Diana; Sparreboom, Alex; Giacomini, Kathleen M.; Pui, Ching-Hon; Evans, William E.; Relling, Mary V.

    2009-01-01

    Purpose Methotrexate plasma concentration is related to its clinical effects. Our aim was to identify the genetic basis of interindividual variability in methotrexate pharmacokinetics in children with newly diagnosed acute lymphoblastic leukemia (ALL). Patients and Methods We performed a genome-wide analysis of 500,568 germline single-nucleotide polymorphisms (SNPs) to identify how inheritance affects methotrexate plasma disposition among 434 children with ALL who received 3,014 courses of methotrexate at 2 to 5 g/m2. SNPs were validated in an independent cohort of 206 patients. Results Adjusting for age, race, sex, and methotrexate regimen, the most significant associations were with SNPs in the organic anion transporter polypeptide, SLCO1B1. Two SNPs in SLCO1B1, rs11045879 (P = 1.7 × 10−10) and rs4149081 (P = 1.7 × 10−9), were in linkage disequilibrium (LD) with each other (r2 = 1) and with a functional polymorphism in SLCO1B1, T521C (rs4149056; r2 > 0.84). rs11045879 and rs4149081 were validated in an independent cohort of 206 patients (P = .018 and P = .017), as were other SLCO1B1 SNPs residing in different LD blocks. SNPs in SLCO1B1 were also associated with GI toxicity (odds ratio, 15.3 to 16.4; P = .03 to .004). Conclusion A genome-wide interrogation identified inherited variations in a plausible, yet heretofore low-priority candidate gene, SLCO1B1, as important determinants of methotrexate's pharmacokinetics and clinical effects. PMID:19901119

  10. Spatio-Temporal Variation and Monsoon Effect on the Temperature Lapse Rate of a Subtropical Island

    Directory of Open Access Journals (Sweden)

    Ching-An Chiu

    2014-01-01

    Full Text Available Temperature lapse rate (TLR has been widely used in the prediction of mountain climate and vegetation and in many ecological models. The aims of this paper are to explore the spatio-temporal variations and monsoon effects on the TLR in the subtropical island of Taiwan with its steep Central Mountain Region (CMR. A TLR analysis using the 32-year monthly mean air temperatures and elevations from 219 weather stations (sea level to 3852 m a.s.l. was performed based on different geographical regions and monsoon exposures. The results revealed that the average TLR for all of Taiwan is -5.17°C-5.17°C km-1, with a general tendency to be steeper in summer and shallower in winter. The results are also shallower than the typical or global average TLR of -6.5°C-6.5°C km-1. During the prevailing northeast monsoon season (winter, the TLR exhibits a contrast between the windward side (steeper, -5.97°C-5.97°C km-1 and the leeward side (shallower, -4.51°C-4.51°C km-1. From the diagnosis on spatial characteristics of monthly cloud amount and vertical atmospheric profiles, this contrasting phenomenon may be explained by the warming effect of onshore stratus clouds (500 - 2500 m depth on cold and dry Siberian monsoon air on the windward side of the CMR. On the southwestern leeward side of the CMR, the low-level (1500 m, the weak ventilation atmosphere and temperature inversion make the TLR shallower than on the windward side.

  11. Variation in copper effects on kairomone-mediated responses in Daphnia pulicaria.

    Science.gov (United States)

    DeMille, C M; Arnott, S E; Pyle, G G

    2016-04-01

    Chemical signals play an integral role in many predator-prey relationships but their effectiveness can be altered by environmental conditions. Prey species can detect predator kairomones, which induce anti-predator defenses. An example of this predator-prey relationship exists between Daphnia spp. and Chaoborus spp.; however, when living in water contaminated with low concentrations of copper (Cu) Daphnia can fail to respond to Chaoborus kairomone and, in turn, become more susceptible to predation. This has implications for Daphnia living in regions with Cu contamination, such as areas where mining activity has resulted in increased levels of metals in the surrounding lakes. We examined kairomone-mediated responses of multiple Daphnia pulicaria clones obtained from 8 lakes in Ontario, Canada, in the absence and presence of environmentally-relevant Cu concentrations. Life history traits and morphological anti-predator defenses were assessed using neonates collected from mothers that were exposed to kairomone and Cu treatments. We found that kairomone-mediated responses and Cu-tolerance varied among D. pulicaria clones. Clones exposed to kairomone, in the absence of Cu additions, had diverse responses, including larger neonates, delayed reproduction, or altered brood size relative to no-kairomone controls. These kairomone-induced responses act as antipredator defense strategies against Chaoborus by preventing predation or stabilizing population growth. When exposed to Cu, two clones were able to respond to kairomone, while four clones no longer induced a response to kairomone. This variation in non-lethal effects of Cu on aquatic organisms suggests that toxicity tests should incorporate multiple genotypes and include predator-prey interactions.

  12. Effect of Water Chemistry Variations on Corrosion of Zr-Alloys for BWR Applications

    International Nuclear Information System (INIS)

    Two reference water chemistry conditions (60 ppb Zn and 60 μg/cm2 Pt/Rh with either 500 ppb O2 and 500 ppb H2O2, or 150 ppb H2) were chosen for testing at 300 deg. C in refreshed autoclaves. For each reference water chemistry, the potential effects due to three chemical impurities of interest to BWRs (33 ppm Na, 10 ppm Li, and 10 ppm EHC fluid) were evaluated. Zircaloy-2 and GNF-Ziron (a Zr-based alloy with higher Fe additions than Zircaloy-2) cladding tubes were tested and the effects of tubing process variation and pre-filming were investigated. Tested channel materials included Zircaloy-2, Zircaloy-4, GNF-Ziron and NSF (a Zr-based alloy with Sn, Nb and Fe additions). The corrosion weight gain and hydrogen absorption were measured up to 12 months of exposure for a given water chemistry condition. Tests under 150 ppb H2 based water chemistry, with or without chemical impurities, generally resulted in greater amounts of corrosion after 12 month exposure compared with 500 ppb O2 and 500 ppb H2O2 based water chemistries. Of the added chemical impurities, only 33 ppm Na addition produced slightly increased corrosion. Under various test conditions, the presence of a thin pre-film resulted in some initial corrosion benefits, but the benefits were no longer evident after 12 months exposure; however, slight hydrogen benefits remained. For GNF-Ziron cladding, hydrogen absorption was generally lower compared with similarly processed Zircaloy-2 under 150 ppb H2 based water chemistry, when corrosion was generally higher. Of the channel material tested, NSF developed the lowest level of hydrogen absorption, particularly under 150 ppb H2 based water chemistries. (authors)

  13. Genetics in endocrinology: genetic variation in deiodinases: a systematic review of potential clinical effects in humans

    NARCIS (Netherlands)

    Verloop, H.; Dekkers, O.M.; Peeters, R.P.; Schoones, J.W.; Smit, J.W.

    2014-01-01

    Iodothyronine deiodinases represent a family of selenoproteins involved in peripheral and local homeostasis of thyroid hormone action. Deiodinases are expressed in multiple organs and thyroid hormone affects numerous biological systems, thus genetic variation in deiodinases may affect multiple clini

  14. Effects of the variation of fundamental constants on Pop III stellar evolution

    OpenAIRE

    Ekstrom, Sylvia; Coc, Alain; Descouvemont, Pierre; Meynet, Georges; Olive, Keith A.; Uzan, Jean-Philippe; Vangioni, Elisabeth

    2009-01-01

    A variation of the fundamental constants is expected to affect the thermonuclear rates important for stellar nucleosynthesis. In particular, because of the very small resonant energies of Be8 and C12, the triple $\\alpha$ process is extremely sensitive to any such variations. Using a microscopic model for these nuclei, we derive the sensitivity of the Hoyle state to the nucleon-nucleon potential allowing for a change in the magnitude of the nuclear interaction. We follow the evolution of 15 an...

  15. Effects of exposure to facial expression variation in face learning and recognition

    OpenAIRE

    Liu, Chang Hong; Chen, Wenfeng; Ward, James

    2014-01-01

    Facial expression is a major source of image variation in face images. Linking numerous expressions to the same face can be a huge challenge for face learning and recognition. It remains largely unknown what level of exposure to this image variation is critical for expression-invariant face recognition. We examined this issue in a recognition memory task, where the number of facial expressions of each face being exposed during a training session was manipulated. Faces were either trained with...

  16. Effects of Genetic Drift and Gene Flow on the Selective Maintenance of Genetic Variation

    OpenAIRE

    Star, Bastiaan; Spencer, Hamish G.

    2013-01-01

    Explanations for the genetic variation ubiquitous in natural populations are often classified by the population–genetic processes they emphasize: natural selection or mutation and genetic drift. Here we investigate models that incorporate all three processes in a spatially structured population, using what we call a construction approach, simulating finite populations under selection that are bombarded with a steady stream of novel mutations. As expected, the amount of genetic variation compa...

  17. The effect of warning stimulus novelty on the P300 and components of the contingent negative variation.

    NARCIS (Netherlands)

    A. Kok

    1978-01-01

    Studied 12 male university students to evaluate the effects of stimulus and response probability on the P300 and on components of the contingent negative variation (CNV) in 3 different reaction tasks. In the 1st task the warning stimulus (S1) indicated that the imperative stimulus (S2) would require

  18. Variation in energy expenditure among black-legged kittiwakes : Effects of activity-specific metabolic rates and activity budgets

    NARCIS (Netherlands)

    Jodice, PGR; Roby, DD; Suryan, RM; Irons, DB; Kaufman, AM; Turco, KR; Visser, GH

    2003-01-01

    We sought to determine the effect of variation in time-activity budgets (TABs) and foraging behavior on energy expenditure rates of parent black-legged kittiwakes (Rissa tridactyla). We quantified TABs using direct observations of radio-tagged adults and simultaneously measured field metabolic rates

  19. Spoken word recognition in early childhood: Comparative effects of vowel, consonant and lexical tone variation.

    Science.gov (United States)

    Singh, Leher; Goh, Hwee Hwee; Wewalaarachchi, Thilanga D

    2015-09-01

    The majority of the world's languages exploit consonants, vowels and lexical tones to contrast the meanings of individual words. However, the majority of experimental research on early language development focuses on consonant-vowel languages. In the present study, the role of consonants, vowels and lexical tones in emergent word knowledge are directly compared in toddlers (2.5-3.5 years) and preschoolers (4-5 years) who were bilingual native learners of a consonant-vowel-tone language (Mandarin Chinese). Using a preferential looking paradigm, participants were presented with correct pronunciations and consonantal, vowel, and tonal variations of known words. Responses to each type of variation were assessed via gaze fixations to a visual target. When their labels were correctly pronounced, visual targets were reliably identified at both age groups. However, in toddlers, there was a high degree of sensitivity to mispronunciations due to variation in lexical tones relative to those due to consonants and vowels. This pattern was reversed in preschoolers, who were more sensitive to consonant and vowel variation than to tone variation. Findings are discussed in terms of properties of tones, vowels and consonants and the respective role of each source of variation in tone languages. PMID:26010558

  20. Indirect genetic effects and the spread of infectious disease: are we capturing the full heritable variation underlying disease prevalence?

    Directory of Open Access Journals (Sweden)

    Debby Lipschutz-Powell

    Full Text Available Reducing disease prevalence through selection for host resistance offers a desirable alternative to chemical treatment. Selection for host resistance has proven difficult, however, due to low heritability estimates. These low estimates may be caused by a failure to capture all the relevant genetic variance in disease resistance, as genetic analysis currently is not taylored to estimate genetic variation in infectivity. Host infectivity is the propensity of transmitting infection upon contact with a susceptible individual, and can be regarded as an indirect effect to disease status. It may be caused by a combination of physiological and behavioural traits. Though genetic variation in infectivity is difficult to measure directly, Indirect Genetic Effect (IGE models, also referred to as associative effects or social interaction models, allow the estimation of this variance from more readily available binary disease data (infected/non-infected. We therefore generated binary disease data from simulated populations with known amounts of variation in susceptibility and infectivity to test the adequacy of traditional and IGE models. Our results show that a conventional model fails to capture the genetic variation in infectivity inherent in populations with simulated infectivity. An IGE model, on the other hand, does capture some of the variation in infectivity. Comparison with expected genetic variance suggests that there is scope for further methodological improvement, and that potential responses to selection may be greater than values presented here. Nonetheless, selection using an index of estimated direct and indirect breeding values was shown to have a greater genetic selection differential and reduced future disease risk than traditional selection for resistance only. These findings suggest that if genetic variation in infectivity substantially contributes to disease transmission, then breeding designs which explicitly incorporate IGEs might help

  1. Indirect Genetic Effects and the Spread of Infectious Disease: Are We Capturing the Full Heritable Variation Underlying Disease Prevalence?

    Science.gov (United States)

    Lipschutz-Powell, Debby; Woolliams, John A.; Bijma, Piter; Doeschl-Wilson, Andrea B.

    2012-01-01

    Reducing disease prevalence through selection for host resistance offers a desirable alternative to chemical treatment. Selection for host resistance has proven difficult, however, due to low heritability estimates. These low estimates may be caused by a failure to capture all the relevant genetic variance in disease resistance, as genetic analysis currently is not taylored to estimate genetic variation in infectivity. Host infectivity is the propensity of transmitting infection upon contact with a susceptible individual, and can be regarded as an indirect effect to disease status. It may be caused by a combination of physiological and behavioural traits. Though genetic variation in infectivity is difficult to measure directly, Indirect Genetic Effect (IGE) models, also referred to as associative effects or social interaction models, allow the estimation of this variance from more readily available binary disease data (infected/non-infected). We therefore generated binary disease data from simulated populations with known amounts of variation in susceptibility and infectivity to test the adequacy of traditional and IGE models. Our results show that a conventional model fails to capture the genetic variation in infectivity inherent in populations with simulated infectivity. An IGE model, on the other hand, does capture some of the variation in infectivity. Comparison with expected genetic variance suggests that there is scope for further methodological improvement, and that potential responses to selection may be greater than values presented here. Nonetheless, selection using an index of estimated direct and indirect breeding values was shown to have a greater genetic selection differential and reduced future disease risk than traditional selection for resistance only. These findings suggest that if genetic variation in infectivity substantially contributes to disease transmission, then breeding designs which explicitly incorporate IGEs might help reduce disease

  2. Extra-anatomical bypass: a surgical option for recurrent aortic coarctation.

    Science.gov (United States)

    Malaj, Alban; Martinelli, Ombretta; Irace, Francesco Giosue'; Jabbour, Jihad; Gossetti, Bruno; Mazzesi, Giuseppe

    2013-01-01

    Background. Balloon aortoplasty with or without stenting is a less invasive alternative to open surgery for the management of recurrent isthmic coarctation. However, in patients with previous small size tube graft, an open surgical correction is mandatory and, in most cases, an anatomical aortic reconstruction is carried out. Methods. We present the case of a 48-year-old woman with recurrent aortic coarctation and systemic hypertension with systolic value around 190-200 mmHg and preoperative systolic pressure gradient 70 mmHg, submitted to an extra-anatomical bypass. Through a median sternotomy, an extra-anatomical bypass from ascending to descending aorta was performed. Results. No intra- or postoperative complications were observed. The postoperative pressure gradient was 10 mmHg and the systolic pressure ranged from 130 to 140 mmHg. Conclusion. The extra-anatomical bypass can be considered an effective and safe alternative to the anatomical aortic reconstruction in the cases with recurrent aortic coarctation unfit for endovascular treatment.

  3. Extra-Anatomical Bypass: A Surgical Option for Recurrent Aortic Coarctation

    Directory of Open Access Journals (Sweden)

    Alban Malaj

    2013-01-01

    Full Text Available Background. Balloon aortoplasty with or without stenting is a less invasive alternative to open surgery for the management of recurrent isthmic coarctation. However, in patients with previous small size tube graft, an open surgical correction is mandatory and, in most cases, an anatomical aortic reconstruction is carried out. Methods. We present the case of a 48-year-old woman with recurrent aortic coarctation and systemic hypertension with systolic value around 190–200 mmHg and preoperative systolic pressure gradient 70 mmHg, submitted to an extra-anatomical bypass. Through a median sternotomy, an extra-anatomical bypass from ascending to descending aorta was performed. Results. No intra- or postoperative complications were observed. The postoperative pressure gradient was 10 mmHg and the systolic pressure ranged from 130 to 140 mmHg. Conclusion. The extra-anatomical bypass can be considered an effective and safe alternative to the anatomical aortic reconstruction in the cases with recurrent aortic coarctation unfit for endovascular treatment.

  4. Comparative Study on Therapeutic Effect between Anatomical Liver Resection and Nonanatomical Liver Resection for Hepatocellular Carcinoma Patients%解剖性与非解剖性肝切除治疗肝细胞癌的疗效比较研究

    Institute of Scientific and Technical Information of China (English)

    池闽辉; 曾永毅; 刘景丰

    2012-01-01

    Objective To compare the short-term and long-term clinical therapeutic effect and safety between anatomical liver resection and nonanatomical liver resection for hepatocellular carcinoma (HCC) patients . Methods One hundred and thirty eight patients with hepatocellular carcinoma underwent liver resection were randomly divided into anatomical liver resection group (n=76) and nonanatomical liver resection group (n=62) . Operative time , the volume of intraoperative blood loss and the rate of blood transfusion , length of hospital stay and the rate of postoperative complication , liver function recovery , recurrence and survival rate in one year after liver resection were compared between the two groups . Results No perioperative death was found in both groups . There were no significantly statistical differences in operative time , the volume of intraoperative blood loss , the rate of blood loss transfusion , postoperative complication and lenght of hospital stay between two groups (P>0 .005) . The rate of satisfactory resection margin (P>2 cm) of anatomical liver resection was higher than that of nonanatomical liver resection(P2 cm)较高,术后1年肿瘤复发率解剖性肝切除术较非解剖性肝切除术组显著降低(P=0.013),术后1年无瘤生存率解剖性肝切除术组较非解剖性肝切除术组延长(P=0.029).结论 解剖性肝切除术是治疗HCC安全、可行和有效的术式.对有适应证的病例应尽可能行解剖性肝切除术,以获得相对较好的疗效和较高的安全性.

  5. Effective variations of peer instruction: The effects of peer discussions, committing to an answer, and reaching a consensus

    Science.gov (United States)

    Lasry, Nathaniel; Charles, Elizabeth; Whittaker, Chris

    2016-08-01

    Peer Instruction (PI) is a widely used student-centered pedagogy, but one that is used differently by different instructors. While all PI instructors survey their students with conceptual questions, some do not allow students to discuss with peers. We studied the effect of peer discussion by polling three groups of students (N = 86) twice on the same set of nine conceptual questions. The three groups differed in the tasks assigned between the first and second poll: the first group discussed, the second reflected in silence, and the third was distracted so they could neither reflect nor discuss. Comparing score changes between the first and second poll, we find minimal increases in the distraction condition (3%), sizable increases in the reflection condition (10%), and significantly larger increases in the peer discussion condition (21%). We also examined the effect of committing to an answer before peer discussion and reaching a consensus afterward. We compared a lecture-based control section to three variations of PI that differed in their requirement to commit to an answer or reach consensus (N = 108). We find that all PI groups achieve greater conceptual learning and traditional problem solving than lecture-based instruction. We find one difference between these groups: the absence of consensus building is related to a significant decrease in expert views and beliefs. Our findings can therefore be used to make two recommendations: always use peer discussions and consider asking students to reach a consensus before re-polling.

  6. Effect of dust charge variation on dust—acoustic solitary waves in a magnetized two—ion—temperature dusty plasma

    Institute of Scientific and Technical Information of China (English)

    XueJu-Kui; LangHe

    2003-01-01

    The effect of dust charge variation on the dust-acoustic solitary structures is investigated in a warm magnetized two-ion-temperature dusty plasma consisting of a negatively and variably charged extremely massive dust fluid and ions of two different temperatures. It is shown that the dust charge variation as well as the presence of a second component of ions would modify the properties of the dust-acoustic solitary structures and may exite both dust-acoustic solitary holes (soliton waves with a density dip) and positive solitons (soliton waves with a density hump).

  7. Effect of dust charge variation on dust-acoustic solitary waves in a magnetized two-ion-temperature dusty plasma

    Institute of Scientific and Technical Information of China (English)

    薛具奎; 郎和

    2003-01-01

    The effect of dust charge variation on the dust-acoustic solitary structures is investigated in a warm magnetized two-ion-temperature dusty plasma consisting of a negatively and variably charged extremely massive dust fluid and ions of two different temperatures. It is shown that the dust charge variation as well as the presence of a second component of ions would modify the properties of the dust-acoustic solitary structures and may excite both dust-acoustic solitary holes (soliton waves with a density dip) and positive solitons (soliton waves with a density hump).

  8. Analysis of the effect on control systems of order variation for fractional-order PIλ Dμ controllers

    Institute of Scientific and Technical Information of China (English)

    ZENG Qing-shan; CAO Guang-yi; ZHU Xin-jian

    2005-01-01

    This paper is concerned with fractional-order PIλDμcontrollers. The definitions and properties of fracti-onal calculus are introduced. The mathematical descriptions of a fractional-order controller and fractionalorder control systems are outlined. The effects on control systems of order variation for fractional-order Piλ Dμ controllers are investigated by qualitative analysis and simulation. The conclusions and simulation examples are given. The results show the fractional-order PIλDμ controller is not sensitive to variation of its order.

  9. Effects of polymorphic variation on the mechanism of Endoplasmic Reticulum Aminopeptidase 1.

    Science.gov (United States)

    Stamogiannos, Athanasios; Koumantou, Despoina; Papakyriakou, Athanasios; Stratikos, Efstratios

    2015-10-01

    Endoplasmic Reticulum Aminopeptidase 1 (ERAP1) generates antigenic peptides for loading onto Major Histocompatibility Class I molecules (MHCI) and can regulate adaptive immune responses. During the last few years, many genetic studies have revealed strong associations between coding Single Nucleotide Polymorphisms (SNPs) in ERAP1 and common human diseases ranging from viral infections to cancer and autoimmunity. Functional studies have established that these SNPs affect enzyme activity resulting to changes in antigenic peptide processing, presentation by MHCI and cellular cytotoxic responses. These disease-associated polymorphisms are, however, located away from the enzyme's active site and are interspersed to different structural domains. As a result, the mechanism by which these SNPs can affect function remains largely elusive. ERAP1 utilizes a complex catalytic mechanism that involves a large conformational change between inactive and active forms and has the unique property to trim larger peptides more efficiently than smaller ones. We analyzed two of the most consistently discovered disease-associated polymorphisms, namely K528R and Q730E, for their effect on the ability of the enzyme to select substrates based on length and to undergo conformational changes. By utilizing enzymatic and computational analysis we propose that disease-associated SNPs can affect ERAP1 function by influencing: (i) substrate length selection and (ii) the conformational distribution of the protein ensemble. Our results provide novel insight on the mechanisms by which polymorphic variation distal from the active site of ERAP1 can translate to changes in function and contribute to immune system variability in humans. PMID:26224046

  10. Indirect effects of precipitation variation on the decomposition process of Mongolian oak (Quercus mongolica) leaf litter

    Institute of Scientific and Technical Information of China (English)

    LI Xuefeng; HAN Shijie; ZHANG Yan

    2007-01-01

    The effect of precipitation variation on the chemistry of Mongolian oak(Quercus mongolica)leaf litters was examined by analyzing litters of Mongolia oak saplings under four precipitation gradients.The decomposing process of these leaf litters in the Mongolian oak dominated forest was assessed using litter bag method.Compared with the litters of the Mongolian oak saplings from the natural precipitation site(A),litters produced by Mongolian oak from the driest precipitation gradient(A450)had significantly higher concentrations of nitrogen(N),phosphorus(P)and potassium(K)while lower acid-insoluble fraction(A/F)concentration.The decomposition study showed that A450 exhibited significantly higher decomposition rate,mineralization rates of N,P and K as well as much shorter N and P net immobilization periods.On the contrary,litters produced by seedlings from wettest gradient(Ass0)showed a totally opposite pattern.Litters from saplings that received comparable precipitation(A650)to those at the natural site(A)had significantly higher N concentration and faster decomposition rate as well as release rates of N,P and K.The mass loss patterns for the four litter types fitted the exponential model and the decay constant(k)can be well predicted by initial AIF/N.During the decomposition period,N concentration was best related to the percentage of mass remaining of the litters with relatively higher AIF concentrations and lower N concentrations,but the percentage of mass remaining of litters with lower AIF concentrations and higher N concentrations correlates strongly with AIF concentration.Our study proved that changes in precipitation significantly altered the litter quality,and therefore indirectly changed the decay process of leaf litters.

  11. Variation in maternal effects and embryonic development rates among passerine species

    Science.gov (United States)

    Martin, T.E.; Schwabl, H.

    2008-01-01

    Embryonic development rates are reflected by the length of incubation period in birds, and these vary substantially among species within and among geographical regions. The incubation periods are consistently shorter in North America (Arizona study site) than in tropical (Venezuela) and subtropical (Argentina) South America based on the study of 83 passerine species in 17 clades. Parents, mothers in particular, may influence incubation periods and resulting offspring quality through proximate pathways, while variation in maternal strategies among species can result from selection by adult and offspring mortality. Parents of long-lived species, as is common in the tropics and subtropics, may be under selection to minimize costs to themselves during incubation. Indeed, time spent incubating is often lower in the tropical and subtropical species than the related north temperate species, causing cooler average egg temperatures in the southern regions. Decreased egg temperatures result in longer incubation periods and reflect a cost imposed on offspring by parents because energy cost to the embryo and risk of offspring predation are both increased. Mothers may adjust egg size and constituents as a means to partially offset such costs. For example, reduced androgen concentrations in egg yolks may slow development rates, but may enhance offspring quality through physiological trade-offs that may be particularly beneficial in longer-lived species, as in the tropics and subtropics. We provide initial data to show that yolks of tropical birds contain substantially lower concentrations of growth-promoting androgens than north temperate relatives. Thus, maternal (and parental) effects on embryonic development rates may include contrasting and complementary proximate influences on offspring quality and deserve further field study among species. ?? 2007 The Royal Society.

  12. Anatomical decomposition in dual energy chest digital tomosynthesis

    Science.gov (United States)

    Lee, Donghoon; Kim, Ye-seul; Choi, Sunghoon; Lee, Haenghwa; Choi, Seungyeon; Kim, Hee-Joung

    2016-03-01

    Lung cancer is the leading cause of cancer death worldwide and the early diagnosis of lung cancer has recently become more important. For early screening lung cancer, computed tomography (CT) has been used as a gold standard for early diagnosis of lung cancer [1]. The major advantage of CT is that it is not susceptible to the problem of misdiagnosis caused by anatomical overlapping while CT has extremely high radiation dose and cost compared to chest radiography. Chest digital tomosynthesis (CDT) is a recently introduced new modality for lung cancer screening with relatively low radiation dose compared to CT [2] and also showing high sensitivity and specificity to prevent anatomical overlapping occurred in chest radiography. Dual energy material decomposition method has been proposed for better detection of pulmonary nodules as means of reducing the anatomical noise [3]. In this study, possibility of material decomposition in CDT was tested by simulation study and actual experiment using prototype CDT. Furthermore organ absorbed dose and effective dose were compared with single energy CDT. The Gate v6 (Geant4 application for tomographic emission), and TASMIP (Tungsten anode spectral model using the interpolating polynomial) code were used for simulation study and simulated cylinder shape phantom consisted of 4 inner beads which were filled with spine, rib, muscle and lung equivalent materials. The patient dose was estimated by PCXMC 1.5 Monte Carlo simulation tool [4]. The tomosynthesis scan was performed with a linear movement and 21 projection images were obtained over 30 degree of angular range with 1.5° degree of angular interval. The proto type CDT system has same geometry with simulation study and composed of E7869X (Toshiba, Japan) x-ray tube and FDX3543RPW (Toshiba, Japan) detector. The result images showed that reconstructed with dual energy clearly visualize lung filed by removing unnecessary bony structure. Furthermore, dual energy CDT could enhance

  13. Effective depth-of-penetration range due to hardness variation for different lots of nominally identical target material

    Institute of Scientific and Technical Information of China (English)

    Patrick FRUEH; Andreas HEINE; Karl Ernst WEBER; Matthias WICKERT

    2016-01-01

    The effect of small variations of target hardness on the depth of penetration for nominally identical target material has not been addressed systematically in publications yet and is often neglected. An investigation of this issue for laboratory-scale long rod projectiles penetrating into semi-infinite rolled-homogeneous-armor steel targets was conducted. The tungsten-heavy-alloy penetrators were of length 90 mm and diameter 6 mm. Five lots of armor steel with a nominal hardness range of 280–330 BHN provided material for the targets. The pursued approach consisted of hardness testing of the targets, in total 17 ballistic experiments at velocities in between 1250 m/s and 1780 m/s and data analysis. A linear regression analysis of penetration vs. hardness shows that a target hardness increase within the given range of 280–330 BHN may result in a reduction of penetration depth of about 5.8 mm at constant velocity. This is equal to a change of−12%at an impact velocity of 1250 m/s. A multiple linear regression analysis included also the influence of yaw angle and impact velocity. It shows that small yaw angles and slight variations of impact velocities provide a smaller variation of the semi-infinite penetration depths than a variation of target hardness within a typical specification span of 50 BHN. For such a span a change in penetration of approximately−4.8 mm due to hardness variation is found, whereas 1° of yaw angle or−10 m/s of velocity variation gives a change of about−1.0 mm respectively−0.9 mm. For the given example, the overwhelming part of the variation is to be attributed to hardness effects–4.8 mm out of 5.8 mm (83%). For nominally identical target material the target hardness thus influences the ballistic test results more severely than the typical scatter in impact conditions.

  14. Anatomic correlations in radiogallium imaging of the peritoneum and retroperitoneum

    International Nuclear Information System (INIS)

    Radiogallium (67Ga) imaging of the abdomen and pelvis has been useful not only in detecting inflammations in these regions, but in pointing out their precise anatomic localization. Once the anatomic site is determined, it is often possible to infer the source of origin of the problem (such as ruptured viscus or pancreatitis). Interpretation of the images depends on recognition of patterns that define known anatomic boundaries such as the transverse mesocolon, root of the small mesentery, perirenal space, and pararenal space, or else show diffuse peritoneal uptake. The anatomic patterns may have continued usefulness in future studies, such as when radiolabeled leukocytes are employed to localize inflammations

  15. Do retractile testes have anatomical anomalies?

    Science.gov (United States)

    Anderson, Kleber M.; Costa, Suelen F.; Sampaio, Francisco J.B.; Favorito, Luciano A.

    2016-01-01

    ABSTRACT Objectives: To assess the incidence of anatomical anomalies in patients with retractile testis. Materials and Methods: We studied prospectively 20 patients (28 testes) with truly retractile testis and compared them with 25 human fetuses (50 testes) with testis in scrotal position. We analyzed the relations among the testis, epididymis and patency of the processus vaginalis (PV). To analyze the relations between the testis and epididymis, we used a previous classification according to epididymis attachment to the testis and the presence of epididymis atresia. To analyze the structure of the PV, we considered two situations: obliteration of the PV and patency of the PV. We used the Chi-square test for contingency analysis of the populations under study (p patent processus vaginalis and epididymal anomalies. PMID:27564294

  16. [Antique anatomical collections for contemporary museums].

    Science.gov (United States)

    Nesi, Gabriella; Santi, Raffaella

    2013-01-01

    Anatomy and Pathology Museum collections display a great biological value and offer unique samples for research purposes. Pathological specimens may be investigated by means of modern radiological and molecular biology techniques in order to provide the etiological background of disease, with relevance to present-day knowledge. Meanwhile, historical resources provide epidemiologic data regarding the socio-economic conditions of the resident populations, the more frequently encountered illnesses and dietary habits. These multidisciplinary approaches lead to more accurate diagnoses also allowing new strategies in cataloguing and musealization of anatomical specimens. Further, once these data are gathered, they may constitute the basis of riedited Museum catalogues feasible to be digitalized and displayed via the Web.

  17. Pulsating extreme helium star BD + 13/sup 0/3224. 2. Ultraviolet fluxes and effective temperature variations

    Energy Technology Data Exchange (ETDEWEB)

    Lynas-Gray, A.E. (University Coll., London (UK). Dept. of Physics and Astronomy; Saint Andrews Univ. (UK). Observatory); Schoenberner, D.; Heber, U. (Kiel Univ. (Germany, F.R.). Inst. fuer Theoretische Physik; Kiel Univ. (Germany, F.R.). Sternwarte); Hill, P.W. (Saint Andrews Univ. (UK). Observatory; Anglo-Australian Observatory, Epping (Australia))

    1984-07-15

    Ultraviolet flux variations are reported for the pulsating extreme helium star BD + 13/sup 0/3224 (V652 Her). Effective temperature and angular radius variations over a cycle are determined from static plane-parallel LTE model atmospheres. When compared with radius changes derived from ground-based spectroscopy, the angular radius variations indicate radial pulsations and correspond to a distance of 1.5 +- 0.1 kpc. BD + 13/sup 0/3224 is thought to be a helium-burning star of 0.7 Msolar masses, which has an envelope contracting as the helium-burning core grows; it is similar to HD 144941 and these two stars may constitute a new sub-class of the hydrogen-deficient stars.

  18. The analysis of trend variations of reference evapotranspiration via eliminating the significance effect of all autocorrelation coefficients

    Science.gov (United States)

    Amirataee, Babak; Montaseri, Majid; Sanikhani, Hadi

    2016-10-01

    Reference evapotranspiration (ET0) is considered a key parameter for evaluating the climatic changes as well as spatial and temporal patterns of parameters influencing the eco-hydrological processes. The analysis of trend variations of this index can be used to determine appropriate strategies in planning and management of water resources. In this paper, the trend variations of monthly and annual ET0 in Urmia Lake basin, located in the northwest of Iran, have been analyzed using data from 14 synoptic stations in the study area. Regarding the significant effect of autocorrelation coefficients with different lags on trend variations of ET0, this paper has resorted to modified Mann-Kendall test via eliminating the significance effect of autocorrelation coefficients with different lags to analyze the trend variations. Furthermore, Theil-Sen estimator has been used to determine the slope of trend line of ET0. The results indicated an increasing trend in ET0 values at all the studied stations. Having used the modified Mann-Kendall test, the values of significant increasing (positive) trend, which were estimated using common Mann-Kendall test, dramatically decreased. As such, the values of only 7 stations have been significant at 95 % level. The results confirmed the need for eliminating the significance effect of autocorrelation coefficients with different lags to determine and evaluate the trend of hydrological variables.

  19. Uncinate Process Variations and Their Relationship with Ostiomeatal Complex: A Pictorial Essay of Multidedector Computed Tomography (MDCT) Findings

    OpenAIRE

    Güngör, Gülay; Okur, Nazan; Okur, Erdoğan

    2016-01-01

    Summary The ostiomeatal complex (OMC) is a key area for the drainage and ventilation of the paranasal sinuses. Stenosis created by inflammation and anatomic variations in this region causes an ideal ground for parasanal sinus infections, by preventing the drainage and ventilation of the sinuses. In today’s diagnostics of paranasal sinus infections, the role of evaluation of OMC anatomical variations and soft tissue pathology has increased.. Knowing the anatomical details is important in terms...

  20. Level variations in speech: Effect on masking release in hearing-impaired listeners.

    Science.gov (United States)

    Reed, Charlotte M; Desloge, Joseph G; Braida, Louis D; Perez, Zachary D; Léger, Agnès C

    2016-07-01

    Acoustic speech is marked by time-varying changes in the amplitude envelope that may pose difficulties for hearing-impaired listeners. Removal of these variations (e.g., by the Hilbert transform) could improve speech reception for such listeners, particularly in fluctuating interference. Léger, Reed, Desloge, Swaminathan, and Braida [(2015b). J. Acoust. Soc. Am. 138, 389-403] observed that a normalized measure of masking release obtained for hearing-impaired listeners using speech processed to preserve temporal fine-structure (TFS) cues was larger than that for unprocessed or envelope-based speech. This study measured masking release for two other speech signals in which level variations were minimal: peak clipping and TFS processing of an envelope signal. Consonant identification was measured for hearing-impaired listeners in backgrounds of continuous and fluctuating speech-shaped noise. The normalized masking release obtained using speech with normal variations in overall level was substantially less than that observed using speech processed to achieve highly restricted level variations. These results suggest that the performance of hearing-impaired listeners in fluctuating noise may be improved by signal processing that leads to a decrease in stimulus level variations. PMID:27475136

  1. Effect of temperature variation on hormonal concentration at various gestation stages in black Bengal goat

    Directory of Open Access Journals (Sweden)

    Binod Kumar

    2015-09-01

    Full Text Available Aim: The present study was conducted to evaluate the effect of risingtemperature on the metabolic as well as the reproductive performance of the black Bengal goat. Materials and Methods: A total 27 numbers of non-pregnant black Bengal goats of the same parity comprised the experimental animals. The selected goats were randomly assigned to 3 groups of 9 each, maintaining uniformity in body weight (average 14-18 kg. Goats in Group-I were kept between the temperature ranges of 35-40°C, in Group-II between 20°Cand 27°C, and Group-III were kept under loose housing system and serve as a control. Goats in all the groups were bred naturally. Blood was collected prior to feeding in the morning on the day 1 (estrus, 20, 45, 90, and 135, expected day of parturition and also 2 days after parturition from goats of all the three groups. Results: It was observed that the level of plasma estrogen decreased (p˂0.05 up to day 45 of gestation, then after increased up to 135 days of gestation and was maximum on expected day of parturition which was significantly (p˂0.05 higher than all the values. Plasma progesterone level increased from day 20 and was the highest on day 90 and then decreased significantly (p˂0.05 on expected date of parturition. The luteinizing hormone value decreased significantly (p˂0.05 on expected day of parturition and day 2 after parturition in all the groups. Follicle stimulating hormone concentration showed a significant (p˂0.05 decrease from day 1 to 2 days after parturition in all the groups. The plasma triiodothyronine (T3 level did not vary between and within the treatment groups at any stage of the experiment. The plasma thyroxine (T4 level varied significantly (p˂0.01 within and (p˂0.05 between groups at all stages of reproduction. A significant (p<0.05 variation in plasma cortisol concentration in all the groups increased significantly until the day of parturition and dropped significantly (p<0.01 in 2 days after

  2. Effect of soil moisture on seasonal variation in indoor radon concentration: modelling and measurements in 326 Finnish houses

    International Nuclear Information System (INIS)

    The effect of soil moisture on seasonal variation in soil air and indoor radon is studied. A brief review of the theory of the effect of soil moisture on soil air radon has been presented. The theoretical estimates, together with soil moisture measurements over a period of 10 y, indicate that variation in soil moisture evidently is an important factor affecting the seasonal variation in soil air radon concentration. Partitioning of radon gas between the water and air fractions of soil pores is the main factor increasing soil air radon concentration. On two example test sites, the relative standard deviation of the calculated monthly average soil air radon concentration was 17 and 26 %. Increased soil moisture in autumn and spring, after the snow melt, increases soil gas radon concentrations by 10-20 %. In February and March, the soil gas radon concentration is in its minimum. Soil temperature is also an important factor. High soil temperature in summer increased the calculated soil gas radon concentration by 14 %, compared with winter values. The monthly indoor radon measurements over period of 1 y in 326 Finnish houses are presented and compared with the modelling results. The model takes into account radon entry, climate and air exchange. The measured radon concentrations in autumn and spring were higher than expected and it can be explained by the seasonal variation in the soil moisture. The variation in soil moisture is a potential factor affecting markedly to the high year-to-year variation in the annual or seasonal average radon concentrations, observed in many radon studies. (authors)

  3. Kinematic and dynamic analysis of an anatomically based knee joint.

    Science.gov (United States)

    Lee, Kok-Meng; Guo, Jiajie

    2010-05-01

    This paper presents a knee-joint model to provide a better understanding on the interaction between natural joints and artificial mechanisms for design and control of rehabilitation exoskeletons. The anatomically based knee model relaxes several commonly made assumptions that approximate a human knee as engineering pin-joint in exoskeleton design. Based on published MRI data, we formulate the kinematics of a knee-joint and compare three mathematical approximations; one model bases on two sequential circles rolling a flat plane; and the other two are mathematically differentiable ellipses-based models with and without sliding at the contact. The ellipses-based model taking sliding contact into accounts shows that the rolling-sliding ratio of a knee-joint is not a constant but has an average value consistent with published measurements. This knee-joint kinematics leads to a physically more accurate contact-point trajectory than methods based on multiple circles or lines, and provides a basis to derive a knee-joint kinetic model upon which the effects of a planar exoskeleton mechanism on the internal joint forces and torque during flexion can be numerically investigated. Two different knee-joint kinetic models (pin-joint approximation and anatomically based model) are compared against a condition with no exoskeleton. The leg and exoskeleton form a closed kinematic chain that has a significant effect on the joint forces in the knee. Human knee is more tolerant than pin-joint in negotiating around a singularity but its internal forces increase with the exoskeleton mass-to-length ratio. An oversimplifying pin-joint approximation cannot capture the finite change in the knee forces due to the singularity effect.

  4. Effects of a Changing Climate on Seasonal Variation in Natural Recharge of Unconfined Coastal Aquifers

    Science.gov (United States)

    Antonellini, Marco; Nella Mollema, Pauline

    2013-04-01

    Irregular rainfall patterns throughout the year result in the discontinuous natural recharge of coastal aquifers, which has an effect on the size of freshwater lenses present in sandy deposits. The thickness of the freshwater lenses is important in the context of farmland salinization and coastal ecosystems survival. This study presents numerical models that simulate continuous and discontinuous recharge in sandy coastal aquifers and the thickness of resulting fresh water lenses under current and future climate scenarios. Temperature data for the period 1960-1990 from LOCCLIM FAO and from the IPCC SRES A1b scenario for 2070-2100, have been used to calculate the potential evapotranspiration. Potential recharge was defined as the difference between the precipitation and potential evapotranspiration in twelve locations around the world: Ameland (The Netherlands), Auckland and Wellington (New Zealand), Hong Kong, Ravenna (Italy), Mekong (Vietnam), Mumbai (India), New Jersey (USA), Nile Delta (Egypt), Kobe and Tokyo (Japan), and Singapore. These locations have shallow coastal aquifers along low lying coasts and comparable aquifer structure, which is the result of similar sediment supply and deposition in the Holocene as well as by the sea level changes from the last ice age to the present time. Particular attention has been paid to temporal variations of natural recharge that can vary from continuous recharge throughout the year to discontinuous recharge. The most dramatic reduction in the magnitude of potential annual recharge by the end of this century will occur at lower latitudes (Mumbai, Singapore, Hong Kong and Mekong). The most pronounced change in length of the dry period occurs for Kobe (Japan) and Singapore even though the total annual amount of recharge remains practically the same. The Influence of variable recharge on the size of freshwater lenses surrounded by saline water is simulated with the SEAWAT model. Models where the recharge is applied

  5. Unscheduled load flow effect due to large variation in the distributed generation in a subtransmission network

    Science.gov (United States)

    Islam, Mujahidul

    A sustainable energy delivery infrastructure implies the safe and reliable accommodation of large scale penetration of renewable sources in the power grid. In this dissertation it is assumed there will be no significant change in the power transmission and distribution structure currently in place; except in the operating strategy and regulatory policy. That is to say, with the same old structure, the path towards unveiling a high penetration of switching power converters in the power system will be challenging. Some of the dimensions of this challenge are power quality degradation, frequent false trips due to power system imbalance, and losses due to a large neutral current. The ultimate result is the reduced life of many power distribution components - transformers, switches and sophisticated loads. Numerous ancillary services are being developed and offered by the utility operators to mitigate these problems. These services will likely raise the system's operational cost, not only from the utility operators' end, but also reflected on the Independent System Operators and by the Regional Transmission Operators (RTO) due to an unforeseen backlash of frequent variation in the load-side generation or distributed generation. The North American transmission grid is an interconnected system similar to a large electrical circuit. This circuit was not planned but designed over 100 years. The natural laws of physics govern the power flow among loads and generators except where control mechanisms are installed. The control mechanism has not matured enough to withstand the high penetration of variable generators at uncontrolled distribution ends. Unlike a radial distribution system, mesh or loop networks can alleviate complex channels for real and reactive power flow. Significant variation in real power injection and absorption on the distribution side can emerge as a bias signal on the routing reactive power in some physical links or channels that are not distinguishable

  6. Anatomic Factors that May Predispose Female Athletes to Anterior Cruciate Ligament Injury.

    Science.gov (United States)

    Cheung, Edward C; Boguszewski, Daniel V; Joshi, Nirav B; Wang, Dean; McAllister, David R

    2015-01-01

    Female athletes are 2 to 10 times more likely to injure their anterior cruciate ligaments (ACL) than male athletes. There has been greater recognition of this gender discrepancy because female participation in competitive athletics has increased. Previous investigators have divided risk factors into hormonal, neuromuscular response, and anatomic subgroups. Gender variation within these groups may help explain the higher incidence of ACL injury in women. The purpose of this article is to review research examining female-specific anatomy that may predispose women to ACL injury. Specifically, we discuss how women may have increased tibial and meniscal slopes, narrower femoral notches, and smaller ACL, which may place the ACL at risk from injury. These anatomic factors, combined with other female-specific risk factors, may help physicians and researchers better understand why women appear to be more prone to ACL injury. PMID:26359837

  7. Variability of anatomical-physiological traits in black locust clones - Robinia pseudoacacia L

    Directory of Open Access Journals (Sweden)

    Orlović Saša S.

    2004-01-01

    Full Text Available Variability within R. pseudoacacia species represents an important factor in selection of fast-growing genotypes. Therefore, it is important to identify superior individuals according to their anatomical and physiological traits. This paper presents the results of a study of genotype variability of the main leaf anatomical (frequency, length and width of stomata, leaflet thickness among veins, leaflet thickness on the main vein, mesophyll thickness, length and width of vascular bundle of main vein and physiological (leaf area, photosynthetic pigments content and content of N P, K, Ca, Na parameters among five clones of Robinia pseudoacacia L. Significant interclonal variations were observed in the investigated parameters. Clone R-56 had the highest N, P, and K concentrations, the largest mesophyll volume and the highest pigment concentration. We concluded that the clone R-56, although without a remarkable leaf area, possesses the ability for high photosynthetic production. The results are going to be used in further work on selection.

  8. The Local Effects of Cosmological Variations in Physical 'Constants' and Scalar Fields I. Spherically Symmetric Spacetimes

    CERN Document Server

    Shaw, D J; Barrow, John D.; Shaw, Douglas J.

    2006-01-01

    We apply the method of matched asymptotic expansions to analyse whether cosmological variations in physical `constants' and scalar fields are detectable, locally, on the surface of local gravitationally bound systems such as planets and stars, or inside virialised systems like galaxies and clusters. We assume spherical symmetry and derive a sufficient condition for the local time variation of the scalar fields that drive varying constants to track the cosmological one. We calculate under number of specific examples in detail by matching the Schwarzschild spacetime to spherically symmetric inhomogeneous Tolman-Bondi metrics in an intermediate region by rigorously construction matched asymptotic expansions on cosmological and local astronomical scales which overlap in an intermediate domain. We conclude that, independent of the details of the scalar-field theory describing the varying 'constant', the condition for cosmological variations to be measured locally is almost always satisfied in physically realistic ...

  9. Reflectance of vegetation, soil, and water. [effects of measurable plant parameters on multispectral signal variations

    Science.gov (United States)

    Wiegand, C. L. (Principal Investigator)

    1974-01-01

    The author has identified the following significant results. Reflectance of crop residues, that are important in reducing wind and water erosion, was more often different from bare soil in band 4 than in bands 5, 6, or 7. The plant parameters leaf area index, plant population, plant cover, and plant height explained 95.9 percent of the variation in band 7 (reflective infrared) digital counts for cotton and 78.2 percent of the variation in digital counts for the combined crops sorghum and corn; hence, measurable plant parameters explain most of the signal variation recorded for corpland. Leaf area index and plant population are both highly correlated with crop yields; since plant population can be readily measured (or possibly inferred from seeding rates), it is useful measurement for calibrating ERTS-type MSS digital data in terms of yield.

  10. The Kepler RR Lyrae SC Data Set: Period Variation and Blazhko Effect

    CERN Document Server

    Stellingwerf, Robert F; Moskalik, Pawel

    2013-01-01

    We study the 1.28 million short cadence {\\it Kepler} data points (Q5-Q14) for RR Lyrae covering 24 cycles of the Blazhko variation, and more than one half of the 4-year modulation of the Blazhko variation. This very rich data set clearly shows variability of the 0.5667 day pulsation period (from 0.5655 to 0.5685 day) with each Blazhko cycle, as well as a variation of the Blazhko period itself (from 39.2 days at amplitude maximum to 38.4 days at amplitude minimum) during the 4 year modulation, as well as a rapid increase in Blazhko period as the new cycle commences.

  11. Effect of population size on genetic variation levels in Capparis spinosa (Capparaceae detected by RAPDs

    Directory of Open Access Journals (Sweden)

    Houshang Nosrati

    2012-07-01

    Full Text Available Background: The population size of plants affects on population genetic variation. Materials and Methods: We studied the impact of population size on genetic variation in populations of Capparis spinosa (caper, Capparaceae using RAPDs in East Azerbaijan (Iran. Within-population genetic diversity was estimated based on Nei`s and Shanonn`s diversity using Popgen, and genetic similarity among the populations was studied from a UPGMA dendrogram based the matrix of Nei’s distances obtained through SHAN. Difference in the level genetic variation between small-sized and large-sized populations was tested using Mann-Whitney U test, and correlation between geographical and genetic distances among populations was examined by Pearson test (SPSS, 11.3. Total genetic variation was partitioned into within and among populations based on AMOVA using Arlequin. Results: The polymorphism levels of RAPDs bands among the populations ranged from 48.8% to 81.4%, and within-population Nei’s diversity varied from 0.1667 to 0.2630. Genetic variation in small-sized populations (0.1667 to 0.1809 was significantly lower than the variations in large-sized populations (0.2158 -0.2630 (N= 7, P0.674, Pearson correlation test. Conclusions: Population size has a dramatic impact on its genetic diversity. The results revealed that fragmentation of caper population in the study region has most likely occurred recently. The low genetic diversity revealed within caper populations indicates high risk of extinction and suggests that urgent conservation action is needed to recover diversity in these populations.

  12. Retromolar foramen: an anatomical study with clinical considerations.

    Science.gov (United States)

    Gamieldien, M Y; Van Schoor, A

    2016-09-01

    The retromolar canal and foramen, an anatomical variation in the mandibular retromolar area, houses and transmits neurovascular elements that may innervate the mandibular third molar and associated tissues. These structures have been implicated in local anaesthetic failure, loss of sensation in the normal distribution of the buccal nerve, and local haemorrhage during surgery. Examination of 885 dry mandibles showed that 70 had a retromolar foramen (8%). There were no significant differences between groups according to age, sex, or ancestry. The mean (SD) distance from molar to retromolar foramen was 16.8 (5.6) mm for the mandibular second molar and 10.5 (3.8) mm for the mandibular third molar. The link between these structures and failure of local anaesthesia seems tenuous at best. Bleeding may not represent a serious complication. Although there may be a possibility of perineural spread of infective and invasive pathology, we know of no reported cases. The only clear evidence of complications associated with a confirmed retromolar foramen seems to be loss of sensation in the normal distribution of the buccal nerve. Even though the retromolar foramen does not seem to be of great clinical importance, it could be a source of anxiety for the inexperienced practitioner. PMID:27354332

  13. Variations of earthquake ground motions with depth and its effect on soil-structure interaction

    International Nuclear Information System (INIS)

    Data from a free-field downhole ground motion array at Lotung, Taiwan indicated that both peak acceleration and response spectra of ground motions varied significantly with depth below the ground surface. Data trends were found to be reasonably consistent with predictions from deconvolution analysis assuming vertically propagating body waves. Soil-structure interaction analyses of a reactor containment model indicated that analyses excluding ground motion variations with depth led to significant overestimation of structural responses. It is concluded that appropriate variations of ground motion with depth should be included in carrying out soil-structure interaction analyses and characterizing foundation input motions for embedded structures

  14. Parametric Anatomical Modeling: A method for modeling the anatomical layout of neurons and their projections

    Directory of Open Access Journals (Sweden)

    Martin ePyka

    2014-09-01

    Full Text Available Computational models of neural networks can be based on a variety of different parameters. These parameters include, for example, the 3d shape of neuron layers, the neurons' spatial projection patterns, spiking dynamics and neurotransmitter systems. While many well-developed approaches are available to model, for example, the spiking dynamics, there is a lack of approaches for modeling the anatomical layout of neurons and their projections. We present a new method, called Parametric Anatomical Modeling (PAM, to fill this gap. PAM can be used to derive network connectivities and conduction delays from anatomical data, such as the position and shape of the neuronal layers and the dendritic and axonal projection patterns. Within the PAM framework, several mapping techniques between layers can account for a large variety of connection properties between pre- and post-synaptic neuron layers. PAM is implemented as a Python tool and integrated in the 3d modeling software Blender. We demonstrate on a 3d model of the hippocampal formation how PAM can help reveal complex properties of the synaptic connectivity and conduction delays, properties that might be relevant to uncover the function of the hippocampus. Based on these analyses, two experimentally testable predictions arose: i the number of neurons and the spread of connections is heterogeneously distributed across the main anatomical axes, ii the distribution of connection lengths in CA3-CA1 differ qualitatively from those between DG-CA3 and CA3-CA3. Models created by PAM can also serve as an educational tool to visualize the 3d connectivity of brain regions. The low-dimensional, but yet biologically plausible, parameter space renders PAM suitable to analyse allometric and evolutionary factors in networks and to model the complexity of real networks with comparatively little effort.

  15. Parametric Anatomical Modeling: a method for modeling the anatomical layout of neurons and their projections.

    Science.gov (United States)

    Pyka, Martin; Klatt, Sebastian; Cheng, Sen

    2014-01-01

    Computational models of neural networks can be based on a variety of different parameters. These parameters include, for example, the 3d shape of neuron layers, the neurons' spatial projection patterns, spiking dynamics and neurotransmitter systems. While many well-developed approaches are available to model, for example, the spiking dynamics, there is a lack of approaches for modeling the anatomical layout of neurons and their projections. We present a new method, called Parametric Anatomical Modeling (PAM), to fill this gap. PAM can be used to derive network connectivities and conduction delays from anatomical data, such as the position and shape of the neuronal layers and the dendritic and axonal projection patterns. Within the PAM framework, several mapping techniques between layers can account for a large variety of connection properties between pre- and post-synaptic neuron layers. PAM is implemented as a Python tool and integrated in the 3d modeling software Blender. We demonstrate on a 3d model of the hippocampal formation how PAM can help reveal complex properties of the synaptic connectivity and conduction delays, properties that might be relevant to uncover the function of the hippocampus. Based on these analyses, two experimentally testable predictions arose: (i) the number of neurons and the spread of connections is heterogeneously distributed across the main anatomical axes, (ii) the distribution of connection lengths in CA3-CA1 differ qualitatively from those between DG-CA3 and CA3-CA3. Models created by PAM can also serve as an educational tool to visualize the 3d connectivity of brain regions. The low-dimensional, but yet biologically plausible, parameter space renders PAM suitable to analyse allometric and evolutionary factors in networks and to model the complexity of real networks with comparatively little effort.

  16. Foundations of Intonational Meaning: Anatomical and Physiological Factors.

    Science.gov (United States)

    Gussenhoven, Carlos

    2016-04-01

    Like non-verbal communication, paralinguistic communication is rooted in anatomical and physiological factors. Paralinguistic form-meaning relations arise from the way these affect speech production, with some fine-tuning by the cultural and linguistic context. The effects have been classified as "biological codes," following the terminological lead of John Ohala's Frequency Code. Intonational morphemes, though arguably non-arbitrary in principle, are in fact heavily biased toward these paralinguistic meanings. Paralinguistic and linguistic meanings for four biological codes are illustrated. In addition to the Frequency Code, the Effort Code, and the Respiratory Code, the Sirenic Code is introduced here, which is based on the use of whispery phonation, widely seen as being responsible for the signaling and perception of feminine attractiveness and sometimes used to express interrogativity in language. In the context of the evolution of language, the relations between physiological conditions and the resulting paralinguistic and linguistic meanings will need to be clarified. PMID:27016315

  17. Tridimensional Regression for Comparing and Mapping 3D Anatomical Structures

    Directory of Open Access Journals (Sweden)

    Kendra K. Schmid

    2012-01-01

    Full Text Available Shape analysis is useful for a wide variety of disciplines and has many applications. There are many approaches to shape analysis, one of which focuses on the analysis of shapes that are represented by the coordinates of predefined landmarks on the object. This paper discusses Tridimensional Regression, a technique that can be used for mapping images and shapes that are represented by sets of three-dimensional landmark coordinates, for comparing and mapping 3D anatomical structures. The degree of similarity between shapes can be quantified using the tridimensional coefficient of determination (2. An experiment was conducted to evaluate the effectiveness of this technique to correctly match the image of a face with another image of the same face. These results were compared to the 2 values obtained when only two dimensions are used and show that using three dimensions increases the ability to correctly match and discriminate between faces.

  18. Diurnal Variations of Summer Precipitation in the Beijing Area and the Possible Effect of Topography and Urbanization

    Institute of Scientific and Technical Information of China (English)

    YIN Shuiqing; LI Weijing; Deliang CHEN; Jee-Hoon JEONG; GUO Wenli

    2011-01-01

    The present study examined the diurnal variations of summer precipitation in the Beijing area by using subdaily precipitation and wind observations. A combined effect of topography and urbanization on the characteristics of diurnal variations was suggested. It was shown that stations located in the plain area exhibited typical night rain peaks, whereas those in the mountainous area exhibited clear afternoon peaks of precipitation diurnal variations. The precipitation peaks were associated with wind fields around the Beijing area, which were found to be highly modulated by mountain-valley circulation and urban-country circulation.The lower-tropospheric wind exhibited a clear diurnal shift in its direction from north at 0800 LST to south at 2000 LST, which reflected mountain-valley circulation. The transitions from valley to mountain wind and the opposite generally happened after sunset and sunrise, respectively, and both occurred earlier for the stations located closer to mountains. By comparing the diurnal variations of precipitation at stations in a northeast suburb, an urban area, and a southwest suburb, it was revealed that the northeast suburb group had the highest normalized rainfall frequency, but the southwest group had the lowest from late afternoon to late evening. On the contrary, in the early morning from about 0200 to 1000 LST, the southwest group and urban group had the highest normalized rainfall frequency. This pattern might originate from the combined effects of mountain-valley topography and urbanization.

  19. Effects of intraleaf variations in carbonic anhydrase activity and gas exchange on leaf C18OO isoflux in Zea mays.

    Science.gov (United States)

    Affek, Hagit P; Krisch, Maria J; Yakir, Dan

    2006-01-01

    Variation in the C18OO content of atmospheric CO2 (delta18Oa) can be used to distinguish photosynthesis from soil respiration, which is based on carbonic anhydrase (CA)-catalyzed 18O exchange between CO2 and 18O-enriched leaf water (delta18Ow). Here we tested the hypothesis that mean leaf delta18Ow and assimilation rates can be used to estimate whole-leaf C18OO flux (isoflux), ignoring intraleaf variations in CA activity and gas exchange parameters. We observed variations in CA activity along the leaf (> 30% decline from the leaf center toward the leaf ends), which were only partially correlated to those in delta18Ow (7 to 21 per thousand), delta18O and delta13C of leaf organic matter (25 to 30 per thousand and -12.8 to -13.2 per thousand, respectively), and substomatal CO2 concentrations (intercellular CO2 concentrations, c(i), at the leaf center were approximately 40% of those at the leaf tip). The combined effect of these variations produced a leaf-integrated isoflux that was different from that predicted based on bulk leaf values. However, because of canceling effects among the influencing parameters, isoflux overestimations were only approximately 10%. Conversely, use of measured parameters from a leaf segment could produce large errors in predicting leaf-integrated C18OO fluxes. PMID:16411935

  20. Anatomical structure of pericarp in Gladiolus imbricatus L. and Iris sibirica L. (Iridaceae

    Directory of Open Access Journals (Sweden)

    Christyna Skrypec

    2014-04-01

    Full Text Available The study of anatomical structure of pericarp in Gladiolus imbricatus reveals that this species has a capsule of Lilium-type, with effective mechanism of dehiscence. While Iris sibiriса has a capsule of Galanthus-type with reduced mechanism of dehiscence.

  1. Review: the effects of secular variation in seawater Mg/Ca on marine biocalcification

    Directory of Open Access Journals (Sweden)

    J. B. Ries

    2009-07-01

    Full Text Available Synchronized transitions in the polymorph mineralogy of the major reef-building and sediment-producing calcareous marine organisms and abiotic CaCO3 precipitates (ooids, marine cements throughout Phanerozoic time is believed to have been caused by tectonically-induced variations in seawater molar Mg/Ca (>2="aragonite seas"; <2="calcite seas". Here, I review a series of experiments in which extant calcifying taxa were reared in experimental seawater formulated over the range of mMg/Ca ratios (1.0 to 5.2 that occurred throughout their geologic history.

    Aragonite-secreting bryopsidalean algae and scleractinian corals and calcite-secreting coccolithophores exhibited higher rates of calcification and growth in the experimental seawaters that favored their skeletal mineral. These results support the assertion that seawater Mg/Ca played an important role in determining which hypercalcifying marine organisms were the major reef-builders and sediment-producers throughout Earth history. The observation that primary production increased along with calcification in mineralogically-favorable seawater is consistent with the hypothesis that calcification promotes photosynthesis within autotrophs through the liberation of CO2.

    The Mg/Ca ratio of calcite secreted by the coccolithophores, coralline algae and reef-dwelling animals (crustacea, urchins, calcareous tube worms declined with reductions in seawater Mg/Ca. Calcifying microbial biofilms varied their mineral polymorph with seawater Mg/Ca (mMg/Ca<2=low Mg calc; mMg/Ca>2=arag+high Mg calc, suggesting a nearly abiotic mode of calcification. These results indicate that biomineralogical control can be partially overridden by ambient seawater Mg/Ca and suggests that modern high Mg calcite organisms probably secreted low Mg calcite in calcite seas of the past. Notably, Mg fractionation in autotrophic organisms was more strongly influenced by changes in

  2. Local Variations in the 13-Suess Effect: A Global and Regional Phenomenon

    Science.gov (United States)

    Swart, P. K.; Okazaki, R.; Waite, A.

    2012-12-01

    The burning of fossil fuel has lowered the δ13C of the atmosphere, a change which is visible in the δ13C of dissolved inorganic carbon in the oceans. Although atmospheric measurements of the δ13C of CO2 have only been routine since 1980, the rate of change in atmospheric δ13C since the start of the industrial revolution can be monitored by measuring the δ13C of skeletal organisms such as sclerosponges and corals. For example, by fitting a polynomial equation to the δ13C data from sclerosponges and then determining the first derivative, a rate of change in δ13C can be calculated which increases from -0.001‰/yr in 1850 to -0.009‰/yr in 1960, and -0.026‰/yr at the present day. In comparison the decrease at the present day in the Pacific is significantly lower (-0.01‰/yr). Although shallow water corals from the Atlantic also show the same overall changes in the δ13C, there are locations such as in the Florida Keys, where the rates of change over the past 50 years have been much greater than the global rate. For example, the rate of change between 1960 and 1990 in two different corals examined growing in Florida Bay was -0.045 and -0.06‰/yr respectively, significantly greater than -0.026. Since 1990 however there have been no further decreases in the δ13C of these corals with the result that the change between 1960 and 2010 agrees with the global change. The high rates of change in δ13C this coral and in fact all the corals in Florida, are punctuated by periods during which the change is considerably less than the rate calculated from the sclerosponge data. We propose that these oscillations result from varying delivery of terrestrial organic material to the coastal zone, probably brought about by variations in water delivery and hence local/regional precipitation. During times of enhanced delivery the δ13C of the coastal dissolved inorganic carbon and hence the δ13C of the corals decreases at a faster rate than the global rate. During periods of

  3. Variational assimilation of streamflow into operational distributed hydrologic models: effect of spatiotemporal adjustment scale

    Directory of Open Access Journals (Sweden)

    H. Lee

    2012-01-01

    Full Text Available State updating of distributed rainfall-runoff models via streamflow assimilation is subject to overfitting because large dimensionality of the state space of the model may render the assimilation problem seriously under-determined. To examine the issue in the context of operational hydrology, we carry out a set of real-world experiments in which streamflow data is assimilated into gridded Sacramento Soil Moisture Accounting (SAC-SMA and kinematic-wave routing models of the US National Weather Service (NWS Research Distributed Hydrologic Model (RDHM with the variational data assimilation technique. Study basins include four basins in Oklahoma and five basins in Texas. To assess the sensitivity of data assimilation performance to dimensionality reduction in the control vector, we used nine different spatiotemporal adjustment scales, where state variables are adjusted in a lumped, semi-distributed, or distributed fashion and biases in precipitation and potential evaporation (PE are adjusted hourly, 6-hourly, or kept time-invariant. For each adjustment scale, three different streamflow assimilation scenarios are explored, where streamflow observations at basin interior points, at the basin outlet, or at both interior points and the outlet are assimilated. The streamflow assimilation experiments with nine different basins show that the optimum spatiotemporal adjustment scale varies from one basin to another and may be different for streamflow analysis and prediction in all of the three streamflow assimilation scenarios. The most preferred adjustment scale for seven out of nine basins is found to be the distributed, hourly scale, despite the fact that several independent validation results at this adjustment scale indicated the occurrence of overfitting. Basins with highly correlated interior and outlet flows tend to be less sensitive to the adjustment scale and could benefit more from streamflow assimilation. In comparison to outlet flow assimilation

  4. Spectral evaluation of aging effects on blood pressure and heart rate variations in healthy subjects.

    Science.gov (United States)

    Singh, D; Vinod, K; Saxena, S C; Deepak, K K

    2006-01-01

    The background to heart rate variability (HRV) and blood pressure variability (BPV), and their determinants and physiological correlates, remain obscure. The impact of age must be taken into account if HRV and BPV are used for predictive purposes in clinical settings. Healthy subjects show wide inter-individual variation in their heart rate behaviour and the factors affecting heart rate dynamics are not well known. This paper has undertaken to evaluate heart rate variability (HRV) and baroreflex sensitivity (BRS) in a random sample of subjects without evidence of heart disease, and to estimate the relation of HRV and BPV behaviour to age. The aim of this study was to analyse the effects of ageing on HRV and BPV for simultaneous recordings of electrocardiograph (ECG) and blood pressure (BP) signals at rest in healthy subjects. We studied eight young (21-34 years old) and eight elderly (68-85 years old) rigorously screened subjects from the Fantasia Database to make the reproducibility and comparability of the results more extensive. Time- and frequency-domain analysis of HRV and BPV was performed on 5-minute ectopic-free recordings. BRS on the heart was estimated by frequency-domain analysis of spontaneous variability of systolic blood pressure (SBP) and RR interval. It has been observed that compared to young the elderly subjects have (i) diminished HRV; (ii) a shift in the power spectral density and median frequency to low frequency side for HRV and to higher frequency side for BPV; and (iii) increased low-frequency alpha index and decreased high-frequency alpha index of BRS with overall alpha index augmented. The results convey that normal ageing in the absence of disease is associated with lesser parasympathetic regulation of heart rate. Thus it is concluded that the age is an important factor to be considered for prognosis and diagnosis by HRV and BPV. For reliable clinical applications, more research needs to be done on a broad spectrum of subjects. In

  5. Effects of exposure to facial expression variation in face learning and recognition.

    Science.gov (United States)

    Liu, Chang Hong; Chen, Wenfeng; Ward, James

    2015-11-01

    Facial expression is a major source of image variation in face images. Linking numerous expressions to the same face can be a huge challenge for face learning and recognition. It remains largely unknown what level of exposure to this image variation is critical for expression-invariant face recognition. We examined this issue in a recognition memory task, where the number of facial expressions of each face being exposed during a training session was manipulated. Faces were either trained with multiple expressions or a single expression, and they were later tested in either the same or different expressions. We found that recognition performance after learning three emotional expressions had no improvement over learning a single emotional expression (Experiments 1 and 2). However, learning three emotional expressions improved recognition compared to learning a single neutral expression (Experiment 3). These findings reveal both the limitation and the benefit of multiple exposures to variations of emotional expression in achieving expression-invariant face recognition. The transfer of expression training to a new type of expression is likely to depend on a relatively extensive level of training and a certain degree of variation across the types of expressions.

  6. Effect of Weakly Transverse Perturbations on Dust Acoustic Solitary Waves with Adiabatic Variation of Dust Charge

    Institute of Scientific and Technical Information of China (English)

    DUANWen-Shan

    2002-01-01

    By employing the reductive perturbation technique we derived a Kadomtsev-Petviashvili equation for unmagnetized dusty plasmas,It suggests that the nonlinear dust acoustic solitary waves with adiabatic variation of dust charge are stable even there are some higher order transverse perturbatoins,There are only rarefactive solitary waves for this system which has been verified analytically in this paper.

  7. Effect of Weakly Transverse Perturbations on Dust Acoustic Solitary Waves with Adiabatic Variation of Dust Charge

    Institute of Scientific and Technical Information of China (English)

    DUAN Wen-Shan

    2002-01-01

    By employing the reductive perturbation technique we derived a Kadomtsev-Petviashvili equation forunmagnetized dusty plasmas. It suggests that the nonlinear dust acoustic solitary waves with adiabatic variation of dustcharge are stable even there are some higher order transverse perturbatoins. There are only rarefactive solitary wavesfor this system which has been verified analytically in this paper.

  8. Effects of exposure to facial expression variation in face learning and recognition.

    Science.gov (United States)

    Liu, Chang Hong; Chen, Wenfeng; Ward, James

    2015-11-01

    Facial expression is a major source of image variation in face images. Linking numerous expressions to the same face can be a huge challenge for face learning and recognition. It remains largely unknown what level of exposure to this image variation is critical for expression-invariant face recognition. We examined this issue in a recognition memory task, where the number of facial expressions of each face being exposed during a training session was manipulated. Faces were either trained with multiple expressions or a single expression, and they were later tested in either the same or different expressions. We found that recognition performance after learning three emotional expressions had no improvement over learning a single emotional expression (Experiments 1 and 2). However, learning three emotional expressions improved recognition compared to learning a single neutral expression (Experiment 3). These findings reveal both the limitation and the benefit of multiple exposures to variations of emotional expression in achieving expression-invariant face recognition. The transfer of expression training to a new type of expression is likely to depend on a relatively extensive level of training and a certain degree of variation across the types of expressions. PMID:25398479

  9. Anatomically based lower limb nerve model for electrical stimulation

    Directory of Open Access Journals (Sweden)

    Soboleva Tanya K

    2007-12-01

    Full Text Available Abstract Background Functional Electrical Stimulation (FES is a technique that aims to rehabilitate or restore functionality of skeletal muscles using external electrical stimulation. Despite the success achieved within the field of FES, there are still a number of questions that remain unanswered. One way of providing input to the answers is through the use of computational models. Methods This paper describes the development of an anatomically based computer model of the motor neurons in the lower limb of the human leg and shows how it can be used to simulate electrical signal propagation from the beginning of the sciatic nerve to a skeletal muscle. One-dimensional cubic Hermite finite elements were used to represent the major portions of the lower limb nerves. These elements were fit to data that had been digitised using images from the Visible Man project. Nerves smaller than approximately 1 mm could not be seen in the images, and thus a tree-branching algorithm was used to connect the ends of the fitted nerve model to the respective skeletal muscle. To simulate electrical propagation, a previously published mammalian nerve model was implemented and solved on the anatomically based nerve mesh using a finite difference method. The grid points for the finite difference method were derived from the fitted finite element mesh. By adjusting the tree-branching algorithm, it is possible to represent different levels of motor-unit recruitment. Results To illustrate the process of a propagating nerve stimulus to a muscle in detail, the above method was applied to the nerve tree that connects to the human semitendinosus muscle. A conduction velocity of 89.8 m/s was obtained for a 15 μm diameter nerve fibre. This signal was successfully propagated down the motor neurons to a selected group of motor units in the muscle. Conclusion An anatomically and physiologically based model of the posterior motor neurons in the human lower limb was developed. This

  10. 16 CFR Figure 1 to Part 1203 - Anatomical Planes

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Anatomical Planes 1 Figure 1 to Part 1203 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION CONSUMER PRODUCT SAFETY ACT REGULATIONS SAFETY STANDARD FOR BICYCLE HELMETS Pt. 1203, Fig. 1 Figure 1 to Part 1203—Anatomical Planes ER10MR98.001...

  11. PC Assisted Anatomical Measurements in 3D Using CT Data

    DEFF Research Database (Denmark)

    Hvidtfeldt, Mogens; Pedersen, Steen

    1999-01-01

    To assess facilities and applications of a programme for a PC based CT measurements in 3D of anatomical angelse in the skeleton.......To assess facilities and applications of a programme for a PC based CT measurements in 3D of anatomical angelse in the skeleton....

  12. An Investigation of Anatomical Competence in Junior Medical Doctors

    Science.gov (United States)

    Vorstenbosch, Marc A. T. M.; Kooloos, Jan G. M.; Bolhuis, Sanneke M.; Laan, Roland F. J. M.

    2016-01-01

    Because of a decrease of the time available for anatomy education, decisions need to be made to reduce the relevant content of the anatomy curriculum. Several expert consensus initiatives resulted in lists of structures, lacking analysis of anatomical competence. This study aims to explore the use of anatomical knowledge by medical doctors in an…

  13. The effect of alloy elements on the density variation of steel melt at the interdendritic region during solidification

    Science.gov (United States)

    Cao, Y. F.; Chen, Y.; Ma, X. P.; Fu, P. X.; Kang, X. H.; Liu, H. W.; Li, D. Z.

    2016-03-01

    Alloying elements in steels have essential effects on the formation of macrosegregation by inducing a density difference between the mushy zone and the bulk melt, and even by the alteration of the solidified microstructure. Hence, in terms of the thermodynamic laws for solidification of an idealized dilute solution, a systematic theoretical analysis on the effect of elements on the density variation of the interdendritic melt is presented for common Fe-based binary alloys. It shows that density variation closely associates with three crucial parameters: the microsegregation parameter λ, the temp-comp-expansion parameter β and the initial composition CL o . With these derived parameters, a simple analytical model is proposed to assess the influence of alloy elements on density change. The theoretical analysis indicates that compared to silicon, the effect of carbon on the density variation cannot be ignored, which is remarkably different from the previous recognition of these two elements. The macrosegregation induced by carbon only is experimentally validated by two dissected 500 kg ingots with different carbon contents. Furthermore, to directly validate the results of theoretical analysis a macrosegregation model with two different microsegregation laws (lever rule and Scheil equation) is established. Then simulations of the convection during solidification in the experimental 500 kg reference ingot are performed for Fe-C and Fe-Si alloys, respectively. It demonstrates that numerically simulated effects of carbon and silicon on the interdendritic convection induced by density inversion are fairly consistent with the analytical predictions.

  14. Does the relative importance of resource competition and architectural effect in floral variation vary with stages of floral ontogeny?

    Institute of Scientific and Technical Information of China (English)

    Chang-Qiu LIU; Shuang-Quan HUANG

    2012-01-01

    Variation in floral allocation within inflorescences has been attributed to resource competition and/or architectural effect.The two hypotheses were extensively studied and both hypotheses were partly supported by previous studies.However,the relative importance of resource competition and architectural effect may vary with stages of floral ontogeny in a species.To detect the effects ofontogenetic stages on floral variation,we manipulated the 6-flowered inflorescences ofAdenophorajasionifolia (Campanulaceae) by early,late,and non-thinning flowers.Our results indicated that pollen and ovule production of the remaining flowers were not significantly different between early and late thinning manipulations,suggesting that floral sex allocation was determined far before flowering,in support of the architectural effect hypothesis.Under hand-pollination treatments,early thinning but not late thinning resulted in a significant increase in seed number and seed set of the remaining flowers.Therefore,the increase in seed production of the remaining flowers related to the floral ontogeny.The resource competition for floral allocation was significant under early thinning rather than late thinning manipulation.Our results suggest that studies on floral variation within inflorescences should take into account the stages of floral ontogeny.

  15. Review of the Historical Evolution of Anatomical Terms

    Directory of Open Access Journals (Sweden)

    Algieri, Rubén D.

    2011-12-01

    Full Text Available Most of the medical terms of Greek origin are traditionally attributed to Hippocrates (460-370 BC. Claudius Galen of Pergamum (130-200 BC developed a classification of bones and joints and described different brain areas. His teachings have remained unchanged for over a thousand years. Andreas Vesalius of Brussels (1514-1564, through the systematic study of human body structure, changed many concepts. He published his work in his production "De humani corporis fabrica libri septem", where a special attention is evident to the discovery and description of new anatomical facts. From here there is a revolution in the morphological sciences, where the same anatomical structure passed to receive different names. In the nineteenth century, the different anatomists in the world decide to meet in order to unify criteria regarding the anatomical structures and determine a only one universal language in the anatomical sciences. In 1895, in Basel (Switzerland it’s approved a list of 5.573 terms, called Basle Nomina Anatomica (BNA and was written in Latin. Eponyms were deleted. In 1903, he founded the International Federation of Associations of anatomists (IFAA. In 1935, in Jena (Germany, approving the Jena Nomina Anatomica (JNA. In 1950, in Oxford, formed the Committee of the International Anatomical Nomenclature (IANC. In 1955, in Paris (France it is agreed to adopt a Latin nomenclature based on the BNA, the Paris Nomina Anatomica (PNA. In 1980, for the first time in Latin America, takes place on the 11th International Congress of Anatomists, Mexico. In 1989, the International Committee of Anatomical Nomenclature, published the sixth edition of the Nomina Anatomica, without review by the IFAA. The same year, the latter established a Federative International Committee of Anatomical Terminology (FICAT. In 1998, he published a new list FICAT: International Anatomical Terminology (TAI, with the structures named in Latin language and their equivalence in

  16. Physical meaning of the equinoctial effect for semi-annual variation in geomagnetic activity

    Directory of Open Access Journals (Sweden)

    A. Yoshida

    2009-05-01

    Full Text Available Physical meaning of the equinoctial effect for semi-annual variation in geomagnetic activity is investigated based on the three-hourly am index and solar wind parameters. When the z component of the interplanetary magnetic field (IMF in geocentric solar magnetospheric (GSM coordinates is southward, am indices are well correlated with BsVx2, where Bs is the southward component of the IMF and Vx is the solar wind velocity in the sun-earth direction. The am-BsVx2 relationship, however, depends on the range of Vx2: the am in higher ranges of Vx2 tends to be larger than am in lower ranges of Vx2 for the same value of BsVx2 for both equinoctial and solstitial epochs. Using the data sets of the same Vx2 range, it is shown that distribution of points in the am-BsVx2 diagram at the solstitial epochs overlaps with that at the equinoctial epochs and the average am values in each BsVx2 bin in solstitial epochs are closely consistent with those in equinoctial epochs, if Vx2 for each point at solstices are reduced to Vx2sin2 (Ψ where Ψ is the geomagnetic colatitude of the sub-solar point. Further, it is shown that monthly averages of the am index in the long period is well correlated with the values of sin2(ψ for the middle day of each month. These findings indicate that the factor that contributes to the generation of geomagnetic disturbance is not the velocity of the solar wind, but the component of the solar wind velocity perpendicular to the dipole axis of the geomagnetic

  17. 低切迹解剖锁定钢板治疗成人锁骨中段骨折的临床疗效%Analysis on the clinical curative effects of low-profile locking anatomic plate therapy on the middle clavicular fracture of adult

    Institute of Scientific and Technical Information of China (English)

    敖荣广; 禹宝庆; 姜新华; 叶秀章; 施继飞; 许大峰

    2015-01-01

    Background Middle clavicular fracture is a clinically common fracture,and there are still disputes over its operation indications.According to literature reports over recent years,in comparison with conservative treatment, operative treatment on middle clavicular fracture with obvious fracture displacement has lower complications (including symptomatic malunion and bone ununion),faster functional rehabilitation and functional result.However,there are some disputes over the selection of internal fixators during operation.In particular,since the patients have higher requirments for appearance and functions,the occurrence rate of internal fixator relevant complications has been gradually rising.However,theoretically,the clinical curative effects of low-profile locking anatomic plate can avoid the traditional clavicular plate related complications to certain extent.During the period from January 2012 to December 12,our department adopted ow-profile locking