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Sample records for anatomical variation effect

  1. Complex anatomic variation in the brachial region.

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    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. PREVALENCE OF ANATOMIC VARIATIONS IN CHRONIC RHINOSINUSITIS.

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    Shrikrishna

    2013-03-01

    Full Text Available ABSTRACT: OBJECTIVE: To determine the prevalence of anatomic variations in patients suffering from chronic rhinosinusitis (CRS and to compare them with normal population. DESIGN: This is a case control study. A prospective s tudy of anatomic variations was done on 100 computed tomography (CT scans of patients with chronic rhinosinusitis. Prevalence of anatomic variations in control group was assessed by studying 100 CT scans of non- CRS patients. RESULTS: Even though proportion of concha bullosa was more among chronic rhinosinusitis patients compared to normal individual s, it was statistically not significant. There was no significant difference in the prevalence of pa radoxical middle turbinate, retroverted uncinate process, overpneumatized ethmoid bulla and s eptal deviation in chronic rhinosinusitis patients compared to normal individuals. There was s ignificantly lesser proportion of individuals having haller cells and agger nasi cell s in chronic rhinosinusitis compared to normal individuals. CONCLUSION: There is no significant prevalence of anatomic vari ations in osteomeatal unit in patients with chronic rhinosinus itis. The anatomic variations may predispose to pathological changes only if they are bi gger in size. More detailed studies are recommended in this regard as a good knowledge of c omplex anatomy of the paranasal sinuses is essential to understand chronic rhinosinusitis a nd to plan its treatment

  3. 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

  4. 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.

  5. 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

  6. Anatomical variation of the origin of the left vertebral artery

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    Patasi B

    2009-08-01

    Full Text Available This paper presents and describes the anatomical variation of the left vertebral artery originating from the arch of aorta as a case report. This variation was found in one of the cadavers at the Division of Clinical and Functional Anatomy, Faculty of Medicine, University of Ottawa. During routine dissection of a male cadaver, in the superior mediastinum and the neck we observed an atypical origin of the left vertebral artery. Atypical origin was compared to the typical origin of the left vertebral artery in the anatomical literature. We compared our findings with different possible variations of the origin of the left vertebral artery reported in the literature. The clinical importance of the variation is discussed.

  7. Tools to analyse and display variations in anatomical delineation

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    Ebert, Martin A.; McDermott, L. N.; Haworth, A.; van der Wath, E.; Hooton, B.

    2012-01-01

    Variations in anatomical delineation, principally due to a combination of inter-observer contributions and image-specificity, remain one of the most significant impediments to geometrically-accurate radiotherapy. Quantification of spatial variability of the delineated contours comprising a structure

  8. Multiple variations of the tendons of the anatomical snuffbox

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    Thwin, San San; Zaini, Fazlin; Than, Myo

    2014-01-01

    INTRODUCTION Multiple tendons of the abductor pollicis longus (APL) in the anatomical snuffbox of the wrist can lead to the development of de Quervain's syndrome, which is caused by stenosing tenosynovitis. A cadaveric study was performed to establish the variations present in the tendons of the anatomical snuffbox in a Malaysian population, in the hope that this knowledge would aid clinical investigation and surgical treatment of de Quervain's tenosynovitis. METHODS Routine dissection of ten upper limbs was performed to determine the variations in the tendons of the anatomical snuffbox of the wrist. RESULTS In all the dissected upper limbs, the APL tendon of the first extensor compartment was found to have several (3–14) tendon slips. The insertion of the APL tendon slips in all upper limbs were at the base of the first metacarpal bone, trapezium and fascia of the opponens pollicis muscle; however, in seven specimens, they were also found to be attached to the fleshy belly of the abductor pollicis brevis muscle. In two specimens, double tendons of the extensor pollicis longus located in the third extensor compartment were inserted into the capsule of the proximal interphalangeal joints before being joined to the extensor expansion. In two other specimens, the first extensor compartment had two osseofibrous tunnels divided by a septum that separated the APL tendon from the extensor pollicis brevis tendon. CONCLUSION Multiple variations were found in the anatomical snuffbox region of the dissected upper limbs. Knowledge of these variations would be useful in interventional radiology and orthopaedic surgery. PMID:24452976

  9. Wood anatomical variation in relation to latitude anf altitude

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    Graaff, van der N.A.; Baas, P.

    1974-01-01

    The wood anatomical variation within 17 eurytherm hardwood genera in relation to altitude and latitude has been studied using wood samples from 52 species. With increasing latitude a miniaturization of secondary xylem elements (shorter vessel members, narrower vessels, shorter and sometimes narrower

  10. Anatomical variation of the origin of the left vertebral artery

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    Patasi B; Yeung A; Goodwin S; Jalali A

    2009-01-01

    This paper presents and describes the anatomical variation of the left vertebral artery originating from the arch of aorta as a case report. This variation was found in one of the cadavers at the Division of Clinical and Functional Anatomy, Faculty of Medicine, University of Ottawa. During routine dissection of a male cadaver, in the superior mediastinum and the neck we observed an atypical origin of the left vertebral artery. Atypical origin was compared to the typical origin of the left ver...

  11. 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.

  12. Anatomical variations of the sciatic nerve, in relation to the piriformis muscle

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    Samara Lewis

    2016-12-01

    Full Text Available Anatomical variations can be seen in any part of the body and unless they are identified through imaging, during surgery, or on autopsy most of them will never be detected. Anatomical variations of the sciatic nerve in relation to the piriformis have been described for many years and so has possible implications these variations might play in certain pathologies, such as sciatica. Identifying the frequency of anatomical variations in the population is relevant to identify patients that might not be treated effectively with standard medical care. These patients might require specialized care due to their unique anatomy. In this study 51 cadavers where examined for anatomical variations in the relation of the sciatic nerve to the piriformis muscle. We found that out of 102 lower limbs examined, 90 contained normal anatomy (89%. We identified two distinct variations of anatomy in the cadavers examined: one variation showing the common fibular branch of the sciatic nerve passing through the piriformis (occurring in 9 out of 102 or 8.8% of lower limbs examined; the second variation was the common fibular branch passing over the piriformis (found in 3 out of the 102 limbs or 2.9%.

  13. 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.

  14. 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.

  15. 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.

  16. Two unusual anatomic variations create a diagnostic dilemma in distal ulnar nerve compression.

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    Kiehn, Mark W; Derrick, Allison J; Iskandar, Bermans J

    2008-09-01

    Diagnosis of peripheral neuropathies is based upon patterns of functional deficits and electrodiagnostic testing. However, anatomic variations can lead to confounding patterns of physical and electrodiagnostic findings. Authors present a case of ulnar nerve compression due to a rare combination of anatomic variations, aberrant branching pattern, and FCU insertion at the wrist, which posed a diagnostic and therapeutic dilemma. The literature related to isolated distal ulnar motor neuropathy and anatomic variations of the ulnar nerve and adjacent structures is also reviewed. This case demonstrates how anatomic variations can complicate the interpretation of clinical and electrodiagnostic findings and underscores the importance of thorough exploration of the nerve in consideration for possible variations.

  17. Anatomical variation of arterial supply to the rabbit spleen.

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    Ikegami, Reona; Tanimoto, Yoshimasa; Kishimoto, Miori; Shibata, Hideshi

    2016-02-01

    The rabbit, which is widely used as an experimental animal and is also popular as a companion animal, has a flat and elongated spleen with the longitudinal hilus running along its visceral surface. The spleen receives via the hilus an arterial supply that is essential for splenic nutrition and normal functioning. However, the distribution and variation of the arteries to the spleen have not been studied in detail. This study investigated anatomical variations of splenic arterial supply in 33 New Zealand White rabbits with a colored latex injection into arteries. We also examined whether the length of the spleen correlated with the number of the splenic branches of the splenic artery. The splenic artery always arose as the first independent branch of the celiac artery and ran along the splenic hilus to usually provide 6 (range, 3 to 10) splenic branches to the spleen. There was a moderate correlation (R=0.6) between the number of splenic branches and the longitudinal length of the spleen. The splenic branches often arose as a trunk or trunks in common with short gastric arteries. The number of common trunk(s) was usually 1 (range, 0 to 4). The data showed that the pattern and number of arterial branches to the spleen varied according to the individual animal, suggesting that such variations should be considered when performing experimental and veterinary surgical treatments in rabbits.

  18. The anatomical variations of sylvian veins and cisterns.

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    Aydin, I H; Tüzün, Y; Takçi, E; Kadioğlu, H H; Kayaoğlu, C R; Barlas, E

    1997-06-01

    The anatomical variations of sylvian vein and cistern were investigated during the pterional approach in 750 operative cases with different pathologies. All patients were operated on at the Neurosurgical Department of Ataturk University Medical School, Erzurum, Turkiye. The patients underwent surgery for the lesions necessitating the right or left pterional approach. The findings were recorded during surgical intervention and observed through the operative sketches of the pathologies, the slides, and videotapes of the operations. In our study, we surgically classified the variations of sylvian vein, according to its branching and draining patterns. Type I: The fronto-orbital (frontosylvian), fronto-parietal (parietosylvian) and anterior temporal (temporosylvian) veins drain into one sylvian vein. Type II: Two superficial sylvian veins with separated basal vein draining into the sphenoparietal and Rosenthal's basal vein. Type III: Two superficial sylvian veins draining into the sphenoparietal and the superior petrosal veins. Type IV: Hypoplastic superficial sylvian vein and the deep one. Four types of sylvian vein variations were defined as follows. The type I was seen in 52.8% (n = 396), the type II was found in 19.2% (n = 144), type III was recorded in 18.2% (n = 137), and type IV, or hypoplastic and deep form was discovered in 9.8% (n = 73) of patients. The coursing of sylvian vein was in the temporal side (Temporal Coursing) in 62.4 percent of the cases (n = 469), in the frontal side (Frontal Coursing) in 25 % of the patients (n = 187) and in 9 percent of the cases (n = 67) in the deep localization (Deep Coursing). Only 3.6% of the cases (n = 27) showed Mixed Coursing. The variations of the sylvian cisterns were classified into three types, according to the relationships between the lateral fronto-orbital gyrus and the superior temporal gyrus. In Sylvian type, the frontal and temporal lobes are loosely (Sylvian Type A, wide and large) or tightly (Sylvian Type B

  19. Pigmentation in Anuran Testes: Anatomical Pattern and Variation

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    Franco-Belussi, Lilian [UNESP; Zieri, Rodrigo [UNESP; de Souza Santos, Lia Raquel; Moresco, Rafaela Maria; Oliveira, Classius de [UNESP

    2009-01-01

    In amphibians, pigmented cells are present in several organs, composing an extracutaneous pigmentary system. Seventeen species from two families were studied to develop a protocol for pigmentary classification. The amount and distribution of these cells are variable, allowing the establishment of anatomical patterns for visceral pigmentation in anuran testes. Anat Rec, 292:178-182, 2009. (C) 2008 Wiley-Liss, Inc.

  20. TRAPEZOID SHAPED OMOHYOIDEUS MUSCLE: An Anatomic Variation seen in Functional Neck Dissection

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    Lokman Uzun; Numan Kokten; Gul Ozbilen Acar

    2015-01-01

    Omohyoid muscle (Om) is an important anatomical landmark in cervical lymph node partition, neck dissection for head and neck cancers and cervical spine surgery. It consists of two bellies united at an angle by an intermediate tendon. Variations in the origin and insertion of the muscle, absence or duplication of the superior or inferior bellies, aberrant position in relation to IJV and sternocleideomastoid muscle have been reported. We report a rare anatomical variation of the Om in this repo...

  1. Triple extensor digiti minimi tendon: An anatomic variation

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    Elif Sari

    2014-01-01

    This case report describes an unusual variation of the extensor digiti minimi tendon discovered during extensor tendon repair in the emergency room. Knowledge of this variation may be helpful for the tendon transfers and tendon surgery that need tendon graft. [Hand Microsurg 2014; 3(2.000): 56-58

  2. 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.

  3. SCIATIC NERVE AND ITS VARIATIONS: AN ANATOMICAL STUDY

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    Anbumani T.L

    2015-06-01

    Full Text Available Background and aims: The Sciatic nerve is the widest nerve of the body, consists of two components namely tibial and common peroneal components, derived from the lumbosacral plexus from the ventral rami of L4 to S3 spinal nerves. The Sciatic nerve usually enters the gluteal region under the piriformis muscle. The purpose of this study is to identify the variations in the course and branching pattern of the sciatic nerve and its relation to the piriformis muscle which may lead to various clinical manifestations like non-discogenic sciatica. Materials and methods: 50 gluteal regions and posterior compartment of thigh from 25 formalin fixed adult cadavers are used for this study, of which one is a female cadaver. Gluteal regions and the posterior aspect of thigh on both sides are dissected to expose the sciatic nerve. Variations in the sciatic nerve and their relationship to piriformis muscle are observed. Results: 41 gluteal regions and posterior compartments of thigh (82% showed normal anatomy of sciatic nerve and also piriformis muscle. 9 regions (18% showed variations in the sciatic nerve, of which 5 regions (10% showed variation of sciatic nerve in relation to piriformis muscle. Other details are explained further in the article. Conclusion: A proper knowledge about the variations of sciatic nerve, its relation to piriformis muscle is must for medical professionals during posterior hip surgeries, sciatic nerve decompression, total hip replacement, sciatic nerve injury during deep intramuscular gluteal injections, failed sciatic nerve block during anaesthetic procedures etc.

  4. 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

  5. Anatomic variation of the iliacus and psoas major muscles

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    Fabrizio PA

    2011-01-01

    Routine dissection has identified a previously unrecorded unilateral variation of the iliacus and psoas muscles in a 91-year-old female cadaver. A variant iliacus muscle belly originated from the superior lateral aspect of the iliac fossa and after traversing the iliac fossa in a nearly horizontal plane, inserted into the psoas major muscle forming a blended iliacus-psoas muscle. The femoral nerve coursed laterally behind the muscle variant to the superior edge of the blended iliacus-psoas. T...

  6. 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.

  7. 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

  8. Anatomic variation of the iliacus and psoas major muscles

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    Fabrizio PA

    2011-02-01

    Full Text Available Routine dissection has identified a previously unrecorded unilateral variation of the iliacus and psoas muscles in a 91-year-old female cadaver. A variant iliacus muscle belly originated from the superior lateral aspect of the iliac fossa and after traversing the iliac fossa in a nearly horizontal plane, inserted into the psoas major muscle forming a blended iliacus-psoas muscle. The femoral nerve coursed laterally behind the muscle variant to the superior edge of the blended iliacus-psoas. The femoral nerve then coursed over the anterior aspect of the muscle variant and continued inferiorly in a typical course toward the inguinal ring. The current findings and clinical significance are discussed.

  9. Anatomical Variation of Equine Internal Maxillary Artery: a Case Study

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    Ernesto Andrés Dalmau Barros

    2012-12-01

    Full Text Available A thematic block is taught in the Veterinary Medicine Program at La Salle University’s Faculty of Agricultural Sciences that is relevant to the basic disciplinary training of future veterinarians. It is the theoretical and practical subject of the anatomy of the head of domestic species, which includes the head of horses. The study is addressed by testing the theory in the exercise of a dissection, and the exploration of the different structures that make up the head. This regional and systematic study includes angiology of the head, where emphasis is made on the branches of the common carotid artery as main vessel that irrigates the head. The common carotid artery ends in the occipital, internal carotid and external carotid arteries; the last one splits into two main terminal branches, namely: the internal maxillary artery and the superficial temporal. Generally, the internal maxillary artery follows a path that is repeated in almost all specimens that are dissected as described by different authors; however, in some cases there may variations in the path of the artery, such as in its branches. The purpose of this work is to inform about a case that arose in a regular class in the anatomy lab during dissection of a horse head where arteries were being studied macroscopically. Dissection showed a variation in the normal path of the internal maxillary artery at the level of lateral pterygoid muscle. The case involves an 11-year old mare that was put down by unqualified personnel outside the campus, and whose head was later severed and sent to the gross anatomy labs of the Veterinary Medicine program at the Faculty of Agricultural Sciences. Given its provenance, it was not possible to know the anamnesis, nor the history of the animal.

  10. 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.

  11. 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.

  12. 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.

  13. An Extremely Rare Anatomical Variation: Abnormal Drainage of the Anterior Interventricular Coronary Vein

    Science.gov (United States)

    Okur, Aylin; Sade, Recep; Ogul, Hayri; Karaca, Leyla; Kantarci, Mecit

    2016-01-01

    Variation of anterior interventricular vein draining into the left atrium is an extremely rare occurrence. Multidetector computed tomography (MDCT) coronary angiography has recently become the gold standard for depicting anatomical variations and anomalies of coronary arteries and veins. We herein have reported the case of a 36-year-old male whose anterior interventricular vein draining into the left atrium was demonstrated by MDCT coronary angiography. PMID:27122958

  14. 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

  15. TRAPEZOID SHAPED OMOHYOIDEUS MUSCLE: An Anatomic Variation seen in Functional Neck Dissection

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    Lokman Uzun

    2015-12-01

    Full Text Available Omohyoid muscle (Om is an important anatomical landmark in cervical lymph node partition, neck dissection for head and neck cancers and cervical spine surgery. It consists of two bellies united at an angle by an intermediate tendon. Variations in the origin and insertion of the muscle, absence or duplication of the superior or inferior bellies, aberrant position in relation to IJV and sternocleideomastoid muscle have been reported. We report a rare anatomical variation of the Om in this report. This variation was observed during neck dissection of a 58 years-old male patient with laryngeal carcinoma. It was noticed that, the superior belly of Om was in a trapezoid shaped unilaterally.

  16. 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.

  17. HPV Vaccine Effective at Multiple Anatomic Sites

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    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

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

    Science.gov (United States)

    Tewari, Jerina; Mishra, Pravash Ranjan; Tripathy, Sujit Kumar

    2015-01-01

    Background: Many authors have reported the anatomical variation of abductor pollicis longus (APL) around the wrist and its association with de Quervain tenosynovitis (DQT), first carpo-metacarpal arthritis, and trapezio-metacarpal subluxation. From Indian subcontinent, there is only one original article and a few case reports on the variability of APL tendon insertion. Materials and Methods: Fifty formaldehyde preserved cadaveric wrists were dissected to look for the anatomical variation of APL in the Indian population. Results: The APL was found with single tendon in 2, double in 31, triple in 8, and quadruple in 8 extremities. A maximum of 6 tendon-slips were found in one cadaveric wrist. In all hands, the APL had at least one attachment to first metacarpal bone and in 46 hands (92%), there was second insertion to the trapezium bone. Of all tendon-slips of APL (n = 126), 44% of tendons (68 tendons) were inserted into the base of the first metacarpal bone. This was followed by the insertion into the trapezium in 42% tendons (52 tendons). 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 the first metacarpal base and trapezium. This variation must be understood by the Indian Orthopedic surgeons as the response to treatment of DQT and reason for first carpo-metacarpal arthritis can be dependent on this anatomical variation. PMID:26538762

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

    OpenAIRE

    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...

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

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    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

  1. Anatomical variations of the lateral nasal wall: The secondary and accessory middle turbinates.

    Science.gov (United States)

    El-Shazly, A E; Poirrier, Anne-Lise; Cabay, J; Lefebvre, P P

    2012-04-01

    The aim of the current anatomical and clinical study was to audit our cases of patients who presented with secondary and/or accessory middle turbinates during a two-year period. We investigated the incidence and the clinical impact of these variations. Twenty-eight patients, 19 males and 9 females with a mean age of 41.5 years, representing different ethnic origins, were diagnosed with double middle turbinates based on endoscopic examination. Of those, 92.8% had a main symptom of refractory frontal headache. A secondary nasal symptom was sensation of blocked nose. Patients who underwent endoscopic surgery (n = 13) for reduction of the extra turbinate, reported significant symptom scores improvement (P < 0.0001) of frontal headache and blocked nose, from means of 9.07 ± 0.26 and 8.57 ± 1.39 to 1 ± 0.31, and 1.42 ± 0.35, respectively. Our results indicate that double middle turbinates may be encountered in rhinology practice (2%). Clinically they may present with refractory headache and blocked nose. Endoscopic surgical approach seems to be an effective way of improving the symptoms.

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

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    Arias Martorell, Júlia

    2014-01-01

    [spa] La Tesis Doctoral con título "the glenohumeral joint of hominoid primates: locomotor correlates, anatomical variation and evolution" trata sobre las adaptaciones anatómicas en la articulación del hombro (articulación glenohumeral) de los primates hominoideos. La acción de las fuerzas ejercidas durante la locomoción modelan la forma de la articulación, determinado el rango de movimientos que los animales pueden alcanzar. Los primates hominoideos destacan por tener articulaciones muy móvi...

  3. Leaf anatomical variation in Cephalaria laevigata (dipsacaceae under different ecological conditions

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    Jakovljević Ksenija

    2014-01-01

    Full Text Available The results of a multivariate morphometric study of leaf anatomical characters in different, geographically distant populations of the taxon Cephalaria laevigata from Serbia and Romania are presented with the aim to reveal the trends of population differentiation. Analyses were performed on a cross-section of 105 leaves collected from 10 populations. In order to establish the overall morphological variation and relationships between individuals from all populations, principal component analyses and canonical discriminant analysis were performed. Clustering analyses were carried out to explore whether the observed anatomical differences are a result of adaptive responses. Regression analysis was performed to identify the level of correlation between leaf anatomical characters and basic orographic, geological and bioclimatic habitat characteristics. Unexpectedly, in most of the characters there was discrepancy between leaf anatomy and climatic conditions, and the characters did not show significant regularities in the variability of their dimension neither in the vertical profile nor in relation to geological substrate. [Projekat Ministarstva nauke Republike Srbije, br. 173030

  4. 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

  5. Anatomic Variation of Sphenoid Sinus and Related Structures in Libyan Population: CT Scan Study

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    Hewaidi GH

    2008-01-01

    Full Text Available Background: Sphenoid sinus is the most inaccessible paranasal sinus, enclosed within the sphenoid bone and intimately related to numerous vital neural and vascular structures. Anatomic variation of the sphenoid sinus is well documented and may complicate surgery in such a place. Objective: To outline the surgically risky anatomic variants of the sphenoid sinus as well as the variable relationships between the sinus and related neurovascular structures, for the safe removal of intrasphenoid and pituitary lesions. Materials and Methods: We undertook a prospective review of 300 paranasal sinus CT scans of Libyan patients; coronal CT scans were obtained by special parameter techniques. We assessed pneumatization of pterygoid process (PP, anterior clinoid process (ACP, and greater wing of sphenoid (GWS; we also examined protrusion and dehiscence of internal carotid artery (ICA, optic nerve (ON, maxillary nerve (MN, and vidian nerve (VN into the sphenoid sinus cavity. Results: Pneumatization of PP, ACP, and GWS were seen in 87 (29%, 46 (15.3%, and 60 patients (20%, respectively. Protrusion of ICA, ON, MN, and VN were noticed in 123 (41%, 107 (35.6%, 73 (24.3%, and 81 patients (27%, respectively; dehiscence of these structures was encountered in 90 (30%, 92 (30.6%, 39 (13%, and 111 patients (37%, respectively. Statistically, there was a highly significant association between ACP pneumatization and ICA protrusion, ACP pneumatization and ON protrusion, PP pneumatization and VN protrusion; and GWS pneumatization and MN protrusion (p-value < 0.001. Conclusion: The sphenoid sinus is highly variable; this variability necessitates a comprehensive understanding of the regional sphenoid sinus anatomy by a detailed CT scan sinus examination before surgery in and around the sinus. This study indicates the possibility of a racial anatomical variation of the sphenoid sinus in the Libyan population.

  6. 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.

  7. Anatomical variations within the deep posterior compartment of the leg and important clinical consequences.

    Science.gov (United States)

    Hislop, M; Tierney, P

    2004-09-01

    The management of musculoskeletal conditions makes up a large part of a sports medicine practitioner's practice. A thorough knowledge of anatomy is an essential component of the armament necessary to decipher the large number of potential conditions that may confront these practitioners. To cloud the issue further, anatomical variations may be present, such as supernumerary muscles, thickened fascial bands or variant courses of nerves and blood vessels, which can themselves manifest as acute or chronic conditions that lead to significant morbidity or limitation of activity. There are a number of contentious areas within the literature surrounding the anatomy of the leg, particularly involving the deep posterior compartment. Conditions such as chronic exertional compartment syndrome, tibial periostitis (shin splints), peripheral nerve entrapment and tarsal tunnel syndrome may all be affected by subtle anatomical variations. This paper primarily focuses on the deep posterior compartment of the leg and uses the gross dissection of cadaveric specimens to describe definitively the anatomy of the deep posterior compartment. Variant fascial attachments of flexor digitorum longus are documented and potential clinical sequelae such as chronic exertional compartment syndrome and tarsal tunnel syndrome are discussed.

  8. A Review on Anatomical Variations of Mental Foramen (Number, Location, Shape, Symmetry, Direction and Size

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    F Ezoddini-Ardakani

    2016-02-01

    Full Text Available Mental foramen is located on the anterior aspect of the mandible that permits the terminal branch of the inferior alveolar nerve and blood vessels to exit. The anatomical variations of mental foramen are of considerable importance in local anesthesia, treatment of the fractures in the parasymphysis area, orthognatic surgeries, implant placement, etc. Regarding the importance of mental foramen in dentistry (from local anesthesia to invasive surgical procedures, this study intends to review the anatomical variations of mental foramen in this study. Absence of mental foramen is rare. On the other hand, prevalence of accessory mental foramen has been estimated lower than 15% in the most studies. The position of mental foramen is normally between first and second premolar teeth or under second premolar tooth in different ethnic groups and bilateral symmetry exists in regard with location in most cases. In most studies, the ratio of distance from mental foramen to symphysis to distance from symphysis to posterior border of ramus has been reported about 1/3.5 to 1/3. Mental foramen is oval or circular in shape and its most common direction is usually posterosuperior. Its size in different studies has been estimated about 2 to 5 millimeters and asymmetry in size is possible on both sides of mandible. Due to variations of mental foramen between various ethnic groups and even different individuals in the same ethnic group, using advanced imaging techniques such as CBCT is recommended in order to gain detailed knowledge of anatomy and morphology of mental foramen before applying invasive surgeries.

  9. 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

  10. 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

  11. [Pyrimidal syndrome and anatomical variations as a cause of insidious sciatic pain].

    Science.gov (United States)

    Ortiz Sánchez, V E; Charco Roca, L M; Soria Quiles, A; Zafrilla Disla, E; Hernandez Mira, F

    2014-11-01

    The case is presented of a 42 year old woman who had been suffering a loss of strength in her left leg for six years. After an extensive diagnostic study, the pain was classified as of functional origin by a diagnosis of exclusion. Since then, the patient has tried all kind of drug treatments and conservative techniques without improvement. After an exhaustive study with inconclusive results, the case was discussed with the Orthopaedics Department, who performed an exploratory surgery, in which compression of the sciatic nerve due to an anatomical variation of the piriformis muscle was observed. Part of the muscle was resected during surgery and the sciatic nerve was freed, after which the patient experienced a great improvement.

  12. 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.

  13. 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.

  14. Anatomic variations of the renal vessels: focus on the precaval right renal artery.

    Science.gov (United States)

    Bouali, Ourdia; Labarre, David; Molinier, François; Lopez, Raphaël; Benouaich, Vincent; Lauwers, Frédéric; Moscovici, Jacques

    2012-07-01

    The aim of this study was to determine the prevalence of precaval right renal artery and to investigate the distribution of renal arteries and veins. We discuss a theory of development of renal vascular variants. We retrospectively reviewed 120 arterial phase contrast material-enhanced spiral computerized tomography scans of the abdomen (1- to 2-mm section thickness) performed during a two-month period. Forty percent of the study group (48 patients) had one artery and one vein on each side, with typical course. There was a 9.17% prevalence of precaval right renal artery: 10 patients had a lower pole accessory artery in precaval position and one patient had the main and the accessory arteries that pass anterior to the inferior vena cava. In these cases, associated variations of renal vessels were higher than in the patients without precaval artery variant. There were multiple arteries in 28.3% of the right kidneys and in 26.7% of the left ones. Variants of the right renal vein consisted in multiple veins in 20% (24 cases). We detected no case of multiple left renal veins, but we described variations of its course (circum- or retroaortic vein) in 9.17% (11 cases). Twenty-six patients (21.7%) had associated variations of the renal pedicle. The current technical support allows for a minimally invasive study of vessels anatomy. In our study the prevalence of a precaval right renal artery appears to be higher than previously reported (9.17%). Knowledge on anatomical variations of right renal artery and associated renal vessels variations has major clinical implications.

  15. Anatomical and morphological spine variation in Gymnocalycium kieslingii subsp. castaneum (Cactaceae)

    Science.gov (United States)

    Gebauer, Roman; Řepka, Radomír; Šmudla, Radek; Mamoňová, Miroslava; Ďurkovič, Jaroslav

    2016-01-01

    Abstract Although spine variation within cacti species or populations is assumed to be large, the minimum sample size of different spine anatomical and morphological traits required for species description is less studied. There are studies where only 2 spines were used for taxonomical comparison amnog species. Therefore, the spine structure variation within areoles and individuals of one population of Gymnocalycium kieslingii subsp. castaneum (Ferrari) Slaba was analyzed. Fifteen plants were selected and from each plant one areole from the basal, middle and upper part of the plant body was sampled. A scanning electron microscopy was used for spine surface description and a light microscopy for measurements of spine width, thickness, cross-section area, fiber diameter and fiber cell wall thickness. The spine surface was more visible and damaged less in the upper part of the plant body than in the basal part. Large spine and fiber differences were found between upper and lower parts of the plant body, but also within single areoles. In general, the examined traits in the upper part had by 8–17% higher values than in the lower parts. The variation of spine and fiber traits within areoles was lower than the differences between individuals. The minimum sample size was largely influenced by the studied spine and fiber traits, ranging from 1 to 70 spines. The results provide pioneer information useful in spine sample collection in the field for taxonomical, biomechanical and structural studies. Nevertheless, similar studies should be carried out for other cacti species to make generalizations. The large spine and fiber variation within areoles observed in our study indicates a very complex spine morphogenesis. PMID:27698579

  16. VARIATIONS OF SACRAL HIATUS IN DRY HUMAN SACRA: AN ANATOMICAL STUDY

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    Rubi Saikia

    2016-07-01

    Full Text Available BACKGROUND Sacrum is a large triangular bone formed by the fusion of 5 sacral vertebrae. It lies obliquely at the posterior part of pelvic cavity between the two hip bones. It encloses a canal called the sacral canal. The lower opening of the sacral canal is called the sacral hiatus. It transmits the 5 th pair of sacral nerves, coccygeal nerves & filum terminale externa. AIMS & OBJECTIVES The aim of the present study is to find out the variations of sacral hiatus in this part of Northeast India. MATERIALS & METHODS The study was carried out in 104 dry human sacra to know the anatomical variations of sacral hiatus. The measurements were carried out with the help of a Vernier calliper, scale & a divider. RESULT & OBSERVATIONS Various shapes of sacral hiatus were observed as follows: Inverted U shaped (53.8%, inverted V shaped (29.8 %, irregular shaped (9.6 %, dumb-bell shaped (5.7 %, bifid (0.9%. The length of the sacral hiatus was found to be between 20-30 mm in 46.1% cases. The apex of the sacral hiatus was at the level of S4 vertebra in 46.1% specimens. The anteroposterior diameter of the sacral canal at the apex of the sacral hiatus ranged from 2-12 mm. CONCLUSIONS Variations of sacral hiatus is very common. The knowledge of such variations will definitely help the anaesthesiologists to take proper step while administering caudal epidural anaesthesia to increase the success rate of caudal epidural block.

  17. Facilitating appreciation of anatomical variation and development of teamwork skills in the gross anatomy laboratory using a cadaver reassignment system.

    Science.gov (United States)

    Sprunger, Leslie K

    2008-01-01

    Developing a mental map of the body in three dimensions incorporating normal anatomical variations is a challenge for students of gross anatomy. Acquisition of this ability is facilitated by frequently reassigning students to work on different specimens in gross anatomy laboratories, a significant departure from traditional teaching strategies. This article analyzes student and faculty experiences with a reassignment system over a six-year period, including effects on early professional development and students' attitudes toward the cadavers. Students were strongly supportive of the method, noting that specimen reassignments facilitated learning, encouraged dissection skill building, and fostered collaborative interactions. Students' perception of the value of the contribution of each cadaver to their education was preserved and, for many, enhanced. Frequent specimen reassignments offer an opportunity to model public accountability for work and some aspects of the relationships between multiple health care teams caring for a patient.

  18. 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.

  19. Anatomic (positional) variation of maxillary wisdom teeth with special regard to the maxillary sinus.

    Science.gov (United States)

    Lanzer, Martin; Pejicic, Rada; Kruse, Astrid L; Schneider, Thomas; Grätz, Klaus W; Lübbers, Heinz-Theo

    2015-01-01

    The removal of wisdom teeth is one of the most common interventions in oral surgery. In order to avoid complications, a profound knowledge of the anatomy of teeth and adjacent tissues is crucial. In the case of maxillary wisdom teeth, their relationship to the maxillary sinus, to the pterygoid fossa, to the maxillary tuber and the adjacent venous plexus is particularly important. Three-dimensional (3D) imaging, for example by means of cone beam computed tomography (CBCT), is increasingly utilized in practice. However, the necessity of CBCT imaging is still a matter of intensive debate. The aim of this study was to describe the anatomic (positional) variation of maxillary wisdom teeth and, based on these findings, to elucidate the additional benefit of such imaging. A retrospective case study was performed using patients examined by means of CBCT imaging in the Department of Dento-Maxillofacial Radiology during the period from 2008 to 2013. Primary study variables comprised the spatial relationship of the teeth to the maxillary sinus, the degree of retention and root development, the covering of the root with bone and mucosa, the root configuration, and the developmental stage of the tooth. In addition, the association of the inclination of teeth in the transversal and sagittal plane with the above variables was evaluated. Descriptive statistical parameters were calculated for all results of the examination. In total, CBCT recordings of 713 maxillary wisdom teeth from 430 patients were evaluated. Their mean age was 29.8 years, and the proportion of male patients slightly prevailed (54.4%). Most teeth exhibited fully developed roots (64.1%). Overall 22.9% of third molars were impacted, 32.3% were retained, and 6.5% were erupting. In more than a third of the patients, wisdom teeth were in occlusion. The inclination of the third molars both in the transversal and sagittal plane was significantly associated with the distance of the root from the maxillary sinus as well

  20. Anatomical variations of the clavicle and main vascular structures in two pediatric patients: subclavicular vein cannulation with supraclavicular approach

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    Oksuz H

    2009-05-01

    Full Text Available Central venous catheterization is a routine application in the management of patients in critical condition. However, the placement of central venous catheters is not without risk. The standard technique for central venous cannulation includes the use of anatomical landmarks. However, an ultrasound-guided method is recommended for catheterization in high-risk patients. In this report, we present two pediatric cases which had anatomical variations of the clavicles and main vascular structures due to cerebral palsy and were treated with mechanical ventilation because of pneumonia. The subclavian vein cannulation was performed using a supraclavicular approach under ultrasound guidance in both cases. We conclude that central venous catheterization of critical patients who have anatomical variations must be performed under ultrasound guidance as it provides greater safety and a higher success rate.

  1. 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.

  2. Piriformis syndrome: implications of anatomical variations, diagnostic techniques, and treatment options.

    Science.gov (United States)

    Cassidy, Lindsey; Walters, Andrew; Bubb, Kathleen; Shoja, Mohammadali M; Tubbs, R Shane; Loukas, Marios

    2012-08-01

    Details of piriformis syndrome, including the proper diagnosis and most effective form of treatment, continue to be controversial. While the cause, diagnosis, and treatment of piriformis syndrome remain elusive, many studies have been conducted to investigate newly developed diagnostic techniques as well as various treatment options for piriformis-induced sciatica. Despite the quantity of literature, few studies have demonstrated statistically significant results that support one form of treatment over another. Thus, despite the evidence supporting the newer treatment methodologies for piriformis syndrome, research should continue. It is important not only to evaluate treatment outcomes based on associated pain relief, but also to investigate the functional and anatomical return that patients experience from these studied treatments in order to fully explore the most effective form of therapy for piriformis syndrome.

  3. 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.

  4. What is expected of the facial nerve in michel aplasia? Anatomic variation.

    Science.gov (United States)

    Zarandy, Masoud Motasaddi; Kouhi, Ali; Kashany, Shervin Sharif; Rabiei, Sohrab; Hajimohamadi, Fatemeh; Rabbani-Anari, Mahtab

    2010-11-01

    We sought better understanding about the facial nerve anatomy in the rare inner ear Michel anomaly to help better define this aplasia and prevent potential complications in surgery on these patients. The data from computed tomography scans and magnetic resonance images of six Michel aplastic ears (three patients) were evaluated for a facial nerve course. Facial nerve course and anatomic landmarks were noted. Based on data obtained from this group of very rare patients, three different facial nerve anatomies were encountered. The first patient had normal-looking mastoid cells, normal middle ear ossicles, and a completely formed facial nerve canal through the middle ear. The second patient had pneumatized mastoid air cells despite an anomalous ossicular chain. This patient also had a facial nerve canal but not through the middle ear. In the third patient, although mastoid cells were present, neither ossicles nor a definite facial nerve canal could be detected. With guidance provided by the anatomy of the other parts of the ear, such as air cells and the ossicular chain, the danger zones posing a high probability of facial nerve injury can be predicted. Although all Michel aplasias may have aplastic petrous bone in common, there are some degrees of variation.

  5. 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.

  6. 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.

  7. 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

  8. 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.

  9. 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.

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

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    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

  11. 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.

  12. An aberrant anatomic variation along the course of the ulnar nerve above the elbow with coexistent cubital tunnel syndrome.

    Science.gov (United States)

    Chow, James C Y; Papachristos, Athanasios A; Ojeda, Alvaro

    2006-10-01

    We report on a patient with an unusual anatomic variation along the course of ulnar nerve above the elbow who had cubital tunnel syndrome. The variation consisted of a cutaneous neural branch that was originating at a distance of approximately 40 mm proximal to the medial epicondyle, and from the radial aspect of the main trunk of ulnar nerve. The branch had a superficial course and it was passing distally, anterior to the medial epicondyle without penetrating the fascia of the flexor muscles origin. Anterior intramuscular transposition of the ulnar nerve was performed leaving the newly found branch over the fascia between the muscles and the adipose subcutaneous tissue.

  13. The evolution of the anatomically modern or advanced Homo sapiens: time, place, process, affinities and variations.

    Science.gov (United States)

    Raghavan, P; Pathmanathan, G; Talwar, I

    2009-06-01

    This paper surveys the opinions expressed in the recent literature on the origins of the anatomically- modern Homo sapiens, and reviews the evidence from cranial and dental morphology argued by proponents of opposing views to support their case. It also critically analyses problems facing the interpretation of the evidence in arriving at a definitive conclusion to the debate.

  14. Anatomic variation in intrahepatic bile ducts: an analysis of intraoperative cholangiograms in 300 consecutive donors for living donor liver transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jin Woo; Kim, Tae Kyoung; Kim, Kyoung Won; Kim, Ah Young; Kim, Pyo Nyun; Ha, Hyun Kwon; Lee, Moon Gyu [Ulsan University College of Medicine, Seoul (Korea, Republic of)

    2003-06-01

    To describe the anatomical variation occurring in intrahepatic bile ducts (IHDs) in terms of their branching patterns, and to determine the frequency of each variation. The study group consisted of 300 consecutive donors for liver transplantation who underwent intraoperative cholangiography. Anatomical variation in IHDs was classified according to the branching pattern of the right anterior and right posterior segmental duct (RASD and RPSD, respectively), and the presence or absence of the first-order branch of the left hepatic duct (LHD), and of an accessory hepatic duct. The anatomy of the intrahepatic bile ducts was typical in 63% of cases (n=188), showed triple confluence in 10% (n=29), anomalous drainage of the RPSD into the LHD in 11% (n=34), anomalous drainage of the RPSD into the common hepatic duct (CHD) in 6% (n=19), anomalous drainage of the RPSD into the cystic duct in 2% (n=6), drainage of the right hepatic duct (RHD) into the cystic duct (n=1), the presence of an accessory duct leading to the CHD or RHD in 5% (n=16), individual drainage of the LHD into the RHD or CHD in 1% (n=4), and unclassified or complex variation in 1% (n=3)

  15. Abductor Hallucis: Anatomical Variation and Its Clinical Implications in the Reconstruction of Chronic Nonhealing Ulcers and Defects of Foot

    Science.gov (United States)

    Chittoria, Ravi Kumar; Pratap, Harsha; Yekappa, Suma Hottigoudar

    2015-01-01

    Abductor hallucis (AH) is an intrinsic muscle of sole of the foot. It is commonly used in the coverage of ankle and heel defects and chronic nonhealing ulcers of the foot; its use is reported to have a favorable long-term outcome. The muscle's apt bulk and size, its simple surgical isolation, absence of donor-site defect, unvaried anatomy, and long neurovascular pedicle are some of the advantages that make it a promising muscle flap. During routine cadaver dissection in the Department of Anatomy of Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Pondicherry, India, we identified an anatomical variation in AH in both feet of a 45-year-old embalmed male Indian cadaver. The variant muscle had innumerable proximal attachments, a majority of them arising atypically in the form of tough tendinous slips from the medial intermuscular septum at the junction of central and tibial components of plantar aponeurosis, the medial surface of first metatarsal and the intermuscular septum separating AH from the flexor hallucis brevis. The tendon: muscle ratio was 1.76, higher than the normal reported ratio of 0.56±0.07. This article highlights the variation noted and its implication for clinicians. On Internet search, we did not come across the variations described in our article. Findings of the anatomical variation reported in this article could benefit surgeons who decide to use AH flaps in the future. PMID:26634184

  16. Anatomically weighted second-order total variation reconstruction of 23Na MRI using prior information from 1H MRI.

    Science.gov (United States)

    Gnahm, Christine; Nagel, Armin M

    2015-01-15

    Sodium ((23)Na) MRI is a noninvasive tool to assess cell viability, which is linked to the total tissue sodium concentration (TSC). However, due to low in vivo concentrations, (23)Na MRI suffers from low signal-to-noise ratio (SNR) and limited spatial resolution. As a result, image quality is compromised by Gibbs ringing artifacts and partial volume effects. An iterative reconstruction algorithm that incorporates prior information from (1)H MRI is developed to reduce partial volume effects and to increase the SNR in non-proton MRI. Anatomically weighted second-order total variation (AnaWeTV) is proposed as a constraint for compressed sensing reconstruction of 3D projection reconstruction (3DPR) data. The method is evaluated in simulations and a MR measurement of a multiple sclerosis (MS) patient by comparing it to gridding and other reconstruction techniques. AnaWeTV increases resolution of known structures and reduces partial volume effects. In simulated MR brain data (nominal resolution Δx(3) = 3 × 3 × 3 mm(3)), the intensity error of four small MS lesions was reduced from (6.9 ± 3.8)% (gridding) to (2.8 ± 1.4)% (AnaWeTV with T2-weighted reference images). Compared to gridding, a substantial SNR increase of 130% was found in the white matter of the MS patient. The algorithm is robust against misalignment of the prior information on the order of the (23)Na image resolution. Features without prior information are still reconstructed with high contrast. AnaWeTV allows a more precise quantification of TSC in structures with prior knowledge. Thus, the AnaWeTV algorithm is in particular beneficial for the assessment of tissue structures that are visible in both (23)Na and (1)H MRI.

  17. Undivided Retromandibular Vein Continuing As External Jugular Vein With Facial Vein Draining Into It : An Anatomical Variation

    Directory of Open Access Journals (Sweden)

    Shahnaz Choudhary, Ashwani K Sharma, Harbans Singh

    2010-10-01

    Full Text Available Despite the fact that the blueprint of the whole body is unravelled, faultlessly during the growth anddevelopment of an animal; but amazingly variations do occur. During routine dissection of head and neckin a middle aged cadaver in the Post Graduate Department of Anatomy of this medical college, we foundvariation in the formation of external jugular vein on both sides, which was formed by the continuation ofundivided trunk of retromandibular vein. The facial vein and posterior auricular vein were the tributaries ofexternal jugular vein. The sound anatomical knowledge of variations of the veins of head and neck isessential to the success of surgical procedures. The embryological evaluation of the above anomaly wasdone and compared with the available literature which showed that the observed variation was rare

  18. What Is Expected of the Facial Nerve in Michel Aplasia? Anatomic Variation

    OpenAIRE

    2010-01-01

    We sought better understanding about the facial nerve anatomy in the rare inner ear Michel anomaly to help better define this aplasia and prevent potential complications in surgery on these patients. The data from computed tomography scans and magnetic resonance images of six Michel aplastic ears (three patients) were evaluated for a facial nerve course. Facial nerve course and anatomic landmarks were noted. Based on data obtained from this group of very rare patients, three different facial ...

  19. Efficient Variational Approach to Multimodal Registration of Anatomical and Functional Intra-Patient Tumorous Brain Data.

    Science.gov (United States)

    Legaz-Aparicio, Alvar-Ginés; Verdú-Monedero, Rafael; Larrey-Ruiz, Jorge; Morales-Sánchez, Juan; López-Mir, Fernando; Naranjo, Valery; Bernabéu, Ángela

    2016-11-29

    This paper addresses the functional localization of intra-patient images of the brain. Functional images of the brain (fMRI and PET) provide information about brain function and metabolism whereas anatomical images (MRI and CT) supply the localization of structures with high spatial resolution. The goal is to find the geometric correspondence between functional and anatomical images in order to complement and fuse the information provided by each imaging modality. The proposed approach is based on a variational formulation of the image registration problem in the frequency domain. It has been implemented as a C/C[Formula: see text] library which is invoked from a GUI. This interface is routinely used in the clinical setting by physicians for research purposes (Inscanner, Alicante, Spain), and may be used as well for diagnosis and surgical planning. The registration of anatomic and functional intra-patient images of the brain makes it possible to obtain a geometric correspondence which allows for the localization of the functional processes that occur in the brain. Through 18 clinical experiments, it has been demonstrated how the proposed approach outperforms popular state-of-the-art registration methods in terms of efficiency, information theory-based measures (such as mutual information) and actual registration error (distance in space of corresponding landmarks).

  20. 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.

  1. 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

  2. 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

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

    Science.gov (United States)

    Araujo Neto, Severino Aires; Franca, Henrique Almeida; de Mello Júnior, Carlos Fernando; Silva Neto, Eulâmpio José; Negromonte, Gustavo Ramalho Pessoa; Duarte, Cláudia Martina Araújo; Cavalcanti Neto, Bartolomeu Fragoso; Farias, Rebeca Danielly da Fonseca

    2015-01-01

    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. PMID:26811552

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

    Directory of Open Access Journals (Sweden)

    Severino Aires Araujo Neto

    2015-12-01

    Full Text Available Abstract 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.

  5. 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)

  6. Variations in the anatomical relationship between the common carotid artery and the internal jugular vein

    Science.gov (United States)

    García, Alberto; Bustamante, Luis; Castillo, José Luis; Sebastián Martínez, Juan

    2015-01-01

    Introduction: The internal jugular vein locates anterior or anterolateral to the common carotid artery in two-thirds of the subjects studied by ultrasound when the head is in a rotated position. Aim: To identify variables associated with the anterior location of the internal jugular vein. Methods: Ultrasound examinations were performed with the patients in the supine position, with the head rotated to the opposite side. The proximal third of the neck was visualized transversely with a 7.5-mHz transducer. The relationship between the vessels was described in accordance with the proportion of the artery overlapped by the vein. Univariate comparisons and a multivariate analysis of potential variables that may affect the anatomic relationships were performed. Results: Seventy-eight patients were included, 44 of whom were men. The patients' ages ranged from 17 to 90 years (median 64.0, interquartile range 41-73). The right and left sides were studied 75 and 73 times, respectively. The vein was located lateral to the artery in 24.3% (95%CI= 17.4-32.2) of the studies, anterolateral in 33.8% (95%CI= 26.2-41.4) and anterior in 41.9% (95%CI= 33.9-49.8). The multivariate analysis identified age group (OR= 3.7, 95% CI 2.1-6.4) and, less significantly, the left side (OR= 1.7, 95%CI= 0.8-3.5) and male gender (OR= 1.2, 95%CI= 0.6-2.7) as variables associated with the anterior position of the vein. Conclusión: The anterior position of the internal jugular vein relative to the common carotid artery increases gradually with age. Additionally, left-sided localization and male sex further increased the probability of an anterior position. PMID:26309339

  7. [An ischemic syndrome of the oculumotor nucleus: associated clinical and anatomical variations on a theme].

    Science.gov (United States)

    Bonnaud, I; Salama, J

    2003-09-01

    Nuclear syndrome of the oculomotor nerve was first described in 1981, it is characterized by the association of an ipsilateral third nerve palsy with a paresis of elevation in the contralateral eye. This syndrome can be caused by vascular or tumoral lesions in the upper midbrain. It is rarely due to ischemic unilateral mesencephalic lesions, because ischemic lesions of the midbrain are usually integrated in a diffuse involvement of the brainstem and the thalamo-sub-thalamic region. In case of nuclear syndrome of the third nerve due to isolated upper midbrain infarct in the paramedian territory, dependent on branches of the basilar artery, oculomotor symptoms are frequently isolated. On the contrary, in fascicular syndromes of the third nerve, resulting from stroke in more lateral territories upon branches of the posterior cerebral artery, many neurological symptoms are associated with the oculomotor signs. We describe 3 patients presenting with a characteristic nuclear syndrome of the third nerve, resulting from a unilateral paramedian ischemic stroke in the upper midbrain, confirmed by cerebral CT scan or MRI examination. Clinical presentation differed in each case, and marked contralateral hemiparesia, cerebellar syndrome and focal asterixis were associated in various ways with the stereotyped oculomotor disorders. In the 3 cases, the nuclear syndrome of the third nerve was associated with fascicular involvement of the nerve, in an unusual clinical picture. The theoretical distinction between nuclear and fascicular syndromes is supported by the anatomical description of the arterial segmentation in the upper midbrain, which remains debated since the first description. According to the variability of clinical presentations, it seems that the arterial territories may be more variable than initially described. Therefore, ischemic lesions of the upper midbrain may involve some vascular borderzones with a high inter-individual variability. Upper midbrain strokes may

  8. Anatomical arrangement of the lobar bronchi, broncho-pulmonary segments and their variations

    Directory of Open Access Journals (Sweden)

    Sathidevi V. K.

    2016-11-01

    Conclusions: In man there is an increase in the number of bronchial generations and alveoli after birth. An increase in their size was noted as well. Thus the study of variations in the pattern of bronchopulmonary segments aids the clinician very much. It is necessary for Thoracic Surgeons, Anaesthetists, Chest physicians, Radiologists, Ultrasonologists, Pathologists and Anatomists for investigative procedures, diagnosis and various treatment modalities including surgeries like segmentectomy. [Int J Res Med Sci 2016; 4(11.000: 4928-4932

  9. Variations in wood anatomical properties and specific gravity of half sib progenies of Populus deltoides

    Institute of Scientific and Technical Information of China (English)

    P. K. Pande; R. C. Dhiman

    2012-01-01

    We studied radial and inter-progeny variations in the dimensions of the wood elements and specific gravity of 21 half sib progenies of Populus deltoides Bartr.ex Marsh.The female parents of half sib progenies were G48 and S7C13 clones.Variance ratio (F) test indicated that inter-progeny variations in the dimensions of wood elements and specific gravity were significant for all wood traits while variations were significant for radial location for specific gravity only.Hierarchical cluster analysis was done by Squared Euclidean Distance for all of 21 progenies considering six wood traits.21 progenies were grouped into 4 clusters.Cluster 1 was the largest cluster with 11 progenies,whereas cluster 3 had only one progeny.Selected progenies in dusters 3 (progeny 155,male) and 4 (progeny 108,196,both female) were highly divergent from the other progenies so they were used in combinations as parents of hybrids to develop new clones with desired characters.Progeny 155 showed higher growth,fiber dimensions,and specific gravity,thus,should be used for the development of new clones.

  10. 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.

  11. 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.

  12. 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...

  13. Clinical features of a rare anatomical variation of the posterior tibial and fibular arteries

    Directory of Open Access Journals (Sweden)

    Pedro Oliveira Portilho

    Full Text Available Abstract The posterior tibial artery normally arises from tibial-fibular trunk at the popliteal fossa, together with the fibular artery. The classic course of the posterior tibial artery is to run between the triceps surae muscle and muscles of the posterior compartment of the leg before continuing its course posteriorly to the medial malleolus, while the fibular artery runs through the lateral margin of the leg. Studies of both arteries are relevant to the fields of angiology, vascular surgery and plastic surgery. To the best of our knowledge, we report the first case of an anastomosis between the posterior tibial artery and the fibular artery in their distal course. The two arteries joined in an unusual “X” format, before division of the posterior tibial artery into plantar branches. We also provide a literature review of unusual variations and assess the clinical and embryological aspects of both arteries in order to contribute to further investigations regarding these vessels.

  14. 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

  15. 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

  16. Impact of anatomical variations of the circle of Willis on the incidence of aneurysms and their recurrence rate following endovascular treatment

    Energy Technology Data Exchange (ETDEWEB)

    Songsaeng, D. [Division of Neuroradiology, Department of Medical Imaging, University of Toronto, Toronto (Canada); Department of Radiology, Siriraj Hospital, Faculty of Medicine, Mahidol University, Bangkok (Thailand); Geibprasert, S.; Willinsky, R. [Division of Neuroradiology, Department of Medical Imaging, University of Toronto, Toronto (Canada); Tymianski, M. [Department of Neurosurgery, Toronto Western Hospital, University of Toronto, Toronto (Canada); TerBrugge, K.G. [Division of Neuroradiology, Department of Medical Imaging, University of Toronto, Toronto (Canada); Krings, T., E-mail: timo.krings@uhn.on.c [Division of Neuroradiology, Department of Medical Imaging, University of Toronto, Toronto (Canada)

    2010-11-15

    Aim: To analyse the impact of anatomical variations of the parent arteries on the incidence and recurrence rate following coil embolization of aneurysms of the anterior (AcoA), posterior communicating artery (PcoA) and basilar artery (BA) tip. Methods: Two hundred and two (96 AcoA, 67 PcoA, and 29 BA) aneurysms in 200 patients were treated with coil embolization between January 2000 and April 2008. Parent artery variations at each location were classified as: AcoA: A1 aplasia versus hypoplasia versus symmetrical size; PcoA: foetal origin versus medium versus small size, BA: cranial versus caudal versus asymmetrical fusion. The incidence of aneurysms and difference between recurrence rates for each group were recorded on follow-up. Results: AcoA, PcoA, and BA aneurysms were more often associated with embryonically earlier vessel wall dispositions (A1 aplasia, foetal PcoA, asymmetrical fusion). Two of these variations were also associated with aneurysm recurrence following coil embolization: asymmetrical A1 segment (p = 0.01), and asymmetrical BA tip (p = 0.02). Conclusions: AcoA, PcoA, and BA tip aneurysms tend to occur more often in anatomically variant parent artery dispositions, some of which are related to aneurysm recurrence following coil embolization. This may relate to a more fragile vessel disposition as it is not fully matured or to altered haemodynamics secondary to the anatomical variations.

  17. 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.

  18. 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…

  19. Lacrimal system ectasia: an anatomical variation? Review of the literature; Ectasia do sistema lacrimal: uma variacao anatomica? Relato de caso e revisao da literatura

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Ricardo Andre de; Silva, Carolina Travassos de Aguiar; Santos, Frederico Guilherme de Paula Lopes; Wagner, Sabrina; Kormann, Claudia Moraes; Haetinger, Rainer Guilherme; Mello, Silvia Marcal Benicio de [Hospital Beneficencia Portuguesa de Sao Paulo, SP (Brazil). Med Imagem]. E-mail: fgpls@yahoo.com.br

    2008-07-01

    The authors report the case of a patient with tear discharge in both eyes. A dacryocystography was obtained and showed marked dilation of the lacrimal system without signs of obstruction. In clinical practice it is common to find distal obstruction of the lacrimal system causing enlargement. The absence of an obstructive factor in our case was considered an anatomical variation. The purpose of this study is to analyze, by reviewing the literature, the normal anatomy and variations of the lacrimal system. It is also described a digital subtraction dacryocystography's technique performed in our institution and the correlation with tomography findings. (author)

  20. Variation in Anatomical Position of Vermiform Appendix among Iranian Population: An Old Issue Which Has Not Lost Its Importance

    Directory of Open Access Journals (Sweden)

    Ahmad Ghorbani

    2014-01-01

    Full Text Available Vermiform appendix has diverse anatomical positions, lengths, and conditions of mesoappendix. Knowing the exact anatomical position of vermiform appendix is important in view of surgeons for on-time diagnosis and management of acute appendicitis. The aim of present study is determination of these characteristics of vermiform appendix among Iranian population. The present study was conducted on 200 bodies, selected from the dead bodies that had been referred to local bureau of legal medicine, Zenjan province, Iran, for medicolegal autopsy since 21 Mar 2010 to 21 Mar 2011. According to the results, the anatomical positions of the appendix were pelvic, subcecal, retroileal, retrocecal, ectopic, and preileal in 55.8%, 19%, 12.5%, 7%, 4.2%, and 1.5% of the bodies, respectively. The mean length of vermiform appendix was 91.2 mm and 80.3 mm in men and women, respectively. Mesoappendix was complete in 79.5% of the bodies. No association was found between sex and anatomical position of vermiform appendix. Anterior anatomical position was the most common position for vermiform appendix. It is inconsistent with most related reports from western countries. It might be possible that some factors, such as race, geographical changes, and dietary habits, play roles in determining the position of vermiform appendix.

  1. 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.)

  2. 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.

  3. 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.

  4. Effects of Instructional Strategies Using Cross Sections on the Recognition of Anatomical Structures in Correlated CT and MR Images

    Science.gov (United States)

    Khalil, Mohammed K.; Paas, Fred; Johnson, Tristan E.; Su, Yung K.; Payer, Andrew F.

    2008-01-01

    This research is an effort to best utilize the interactive anatomical images for instructional purposes based on cognitive load theory. Three studies explored the differential effects of three computer-based instructional strategies that use anatomical cross-sections to enhance the interpretation of radiological images. These strategies include:…

  5. 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.

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

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    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.

  7. 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

  8. 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.

  9. 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.

  10. 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.

  11. An effective manual deboning method to prepare intact mouse nasal tissue with preserved anatomical organization.

    Science.gov (United States)

    Dunston, David; Ashby, Sarah; Krosnowski, Kurt; Ogura, Tatsuya; Lin, Weihong

    2013-08-10

    The mammalian nose is a multi-functional organ with intricate internal structures. The nasal cavity is lined with various epithelia such as olfactory, respiratory, and squamous epithelia which differ markedly in anatomical locations, morphology, and functions. In adult mice, the nose is covered with various skull bones, limiting experimental access to internal structures, especially those in the posterior such as the main olfactory epithelium (MOE). Here we describe an effective method for obtaining almost the entire and intact nasal tissues with preserved anatomical organization. Using surgical tools under a dissecting microscope, we sequentially remove the skull bones surrounding the nasal tissue. This procedure can be performed on both paraformaldehyde-fixed and freshly dissected, skinned mouse heads. The entire deboning procedure takes about 20-30 min, which is significantly shorter than the experimental time required for conventional chemical-based decalcification. In addition, we present an easy method to remove air bubbles trapped between turbinates, which is critical for obtaining intact thin horizontal or coronal or sagittal sections from the nasal tissue preparation. Nasal tissue prepared using our method can be used for whole mount observation of the entire epithelia, as well as morphological, immunocytochemical, RNA in situ hybridization, and physiological studies, especially in studies where region-specific examination and comparison are of interest.

  12. Common celiacomesenteric trunk: a rare anatomic variation Tronco único celíaco-mesentérico: uma variante anatômica rara

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    K. Sridhar Varma

    2009-09-01

    Full Text Available Common celiacomesenteric trunk, with the celiac and superior mesenteric arteries having a common origin from the aorta, is the least frequently reported anatomic variation of all abdominal vascular anomalies. Knowledge of variations concerning the celiac trunk and superior mesenteric artery are of great importance for both surgical approaches and angiographic examinations. Clinicians should keep in mind these variations to avoid complications.O tronco único celíaco-mesentérico, com as artérias celíaca e mesentérica superior tendo uma origem comum a partir da aorta, é a variante anatômica menos reportada dentre todas as anomalias vasculares abdominais. Conhecer as variantes do tronco celíaco e da artéria mesentérica superior é de grande importância tanto para abordagens cirúrgicas quanto para exames angiográficos. É importante que os médicos tenham em mente essas variantes a fim de evitar complicações.

  13. Variations in the anatomical relationship between the common carotid artery and the internal jugular vein: An ultrasonographic study

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    Mauricio Umaña Perea

    2015-07-01

    Full Text Available Introduction:The internal jugular vein locates anterior or anterolateral to the common carotid artery in two-thirds of the subjects studied by ultrasound when the head is in a rotated position.Aim:To identify variables associated with the anterior location of the internal jugular vein.Methods:Ultrasound examinations were performed with the patients in the supine position, with the head rotated to the opposite side. The proximal third of the neck was visualized transversely with a 7.5-mHz transducer. The relationship between the vessels was described in accordance with the proportion of the artery overlapped by the vein. Univariate comparisons and a multivariate analysis of potential variables that may affect the anatomic relationships were performed.Results:Seventy-eight patients were included, 44 of whom were men. The patients' ages ranged from 17 to 90 years (median 64.0, interquartile range 41-73. The right and left sides were studied 75 and 73 times, respectively. The vein was located lateral to the artery in 24.3% (95%CI= 17.4-32.2 of the studies, anterolateral in 33.8% (95%CI= 26.2-41.4 and anterior in 41.9% (95%CI= 33.9-49.8. The multivariate analysis identified age group (OR= 3.7, 95% CI 2.1-6.4 and, less significantly, the left side (OR= 1.7, 95%CI= 0.8-3.5 and male gender (OR= 1.2, 95%CI= 0.6-2.7 as variables associated with the anterior position of the vein.Conclusión:The anterior position of the internal jugular vein relative to the common carotid artery increases gradually with age. Additionally, left-sided localization and male sex further increased the probability of an anterior position.

  14. 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...

  15. Anatomical variation in the anterolateral ligament of the knee and a new dissection technique for embalmed cadaveric specimens.

    Science.gov (United States)

    Parker, Matthew; Smith, Heather F

    2016-12-18

    Claes et al. recently documented and described the anterolateral ligament (ALL) of the knee, demonstrating its existence in 97% of their samples. Here, we further examined the anatomy of this ligament, documented its morphological variation, and assessed the feasibility of its dissection in preserved cadaveric specimens. To achieve this, we dissected 53 preserved cadaveric knees and documented their morphological variation in the anterolateral ligament. The originally described dissection technique for identifying and following the ALL requires flexion of the knee, a state which is often not possible in stiff, preserved cadavers. Here, we describe and confirm the feasibility of an alternate dissection technique in which the quadriceps femoris tendon is incised, for use on specimens in which flexion of the undissected knee is not possible. We also identify a novel technique for assessing whether the anterolateral ligament is absent from a specimen or has simply been obliterated or overlooked, using the lateral inferior genicular vasculature. These dissection techniques have great potential for the dissection of preserved cadavers used in gross anatomy laboratories, and we discuss the applications of such an approach in student-led dissections. Our dissections also uncovered noticeable variation in the anterolateral ligament course and position. Most notably, it often inserts significantly more laterally than the classical presentation (30.2%), or originates more proximally with superficial fibers extending superiorly and laterally over the distal femur (7.5%).

  16. 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.

  17. Variations in abductor pollicis longus and extensor pollicis brevis tendons in the Quervain syndrome: a surgical and anatomical study.

    Science.gov (United States)

    Kulthanan, Teerawat; Chareonwat, Boonsong

    2007-01-01

    Eighty-two wrists of Thai cadavers and the wrists of 66 patients with de Quervain syndrome were studied, and the variation in the number of tendons and the fibro-osseous tunnel in the first extensor compartment were recorded. The abductor pollicis longus had more than one tendon in 73 of the cadavers (89%) and in 32 of the patients (49%) (p Quervain syndrome (p = 0.01). The results indicate that the number of fibro-osseous tunnels and multiple compartments in the first extensor compartment may be associated with a predisposition to de Quervain syndrome.

  18. 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.)

  19. The effect of aging on the anatomic position of the thyroid gland.

    Science.gov (United States)

    Bann, Darrin V; Kim, Yesul; Zacharia, Thomas; Goldenberg, David

    2017-03-01

    Thyroid disease is common among elderly patients, frequently necessitating thyroid gland examination, imaging, and surgery. However, no prior studies have determined the effect of age on the anatomic position of the thyroid gland in the anterior neck. We hypothesized that the thyroid gland resides at a more caudal position in the neck in elderly patients as compared to younger patients. Head and neck CT scans were collected from 122 atraumatic patients without thyroid disease aged 18-39 years, 40-59 years, 60-79 years, and 80+ years. Measurements of thyroid gland position and other aspects of head and neck anatomy were conducted in the mid-sagittal plane. The distance between the thyroid gland and the sternal notch decreased from 45 ± 10.4 mm in the 18-39 age group to 30.8 ± 9 mm in the 80+ age group (P gland did not change significantly relative to anatomic landmarks in the head or neck, although the trachea was angled more closely to the horizontal plane in elderly patients (P thyroid gland position was dependent on changes in cervical spine height, hyoid bone to hard palate distance, and tracheal angle (P = 1.7 × 10(-11) ; r(2)  = 0.37). Clinicians should be aware of the more caudad positioning of the gland when planning surgery or screening for thyroid disease in the elderly. Clin. Anat. 30:205-212, 2017. © 2016 Wiley Periodicals, Inc.

  20. 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.

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

    OpenAIRE

    Edy Eime Pereira Baraúna; José Tarcísio Lima; Renato da Silva Vieira; José Reinaldo Moreira da Silva; Thiago Campos Monteiro

    2014-01-01

    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 ai...

  2. 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.

  3. A comparison of anatomical and dosimetric variations in the first 15 fractions, and between fractions 16 and 25, of intensity-modulated radiotherapy for nasopharyngeal carcinoma.

    Science.gov (United States)

    Yang, Haihua; Tu, Yu; Wang, Wei; Hu, Wei; Ding, Weijun; Yu, Changhui; Zhou, Chao

    2013-11-04

    The purpose of this study was to compare anatomical and dosimetric variations in first 15 fractions, and between fractions 16 and 25, during intensity-modulated radiotherapy (IMRT) for nasopharyngeal carcinoma (NPC). Twenty-three NPC patients who received IMRT in 33 fractions were enrolled. Each patient had two repeat computed tomography (CT) scans before the 16th and 25th fraction. Hybrid IMRT plans were generated to evaluate the dosimetric changes. There was a significant decrease of the transverse diameter of nasopharyngeal and neck as well as gross tumor volume (GTV) in the primary nasopharyngeal carcinoma (GTVnx) and involved lymph nodes (GTVnd) during the first 15 fractions, and between fraction 16 and 25 (p fractions treatment compared to that between fraction 16 and 25 (p fractions (p fraction 16 and 25. While the maximum dose to the spinal cord was significantly increased both in the first 15 fractions, and between fraction 16 and 25 (p fractions compared to that between fraction 16 and 25 (p fractions, and between fractions 16 and 25, of IMRT.

  4. 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.

  5. The effect of increased ambient lighting on detection accuracy in uniform and anatomical backgrounds

    Science.gov (United States)

    Pollard, Benjamin J.; Chawla, Amarpreet S.; Hashimoto, Noriyuki; Samei, Ehsan

    2008-03-01

    Under typical dark conditions found in reading rooms, a reader's pupils will contract and dilate as the visual focus intermittently shifts between the high luminance monitor and the darker background wall, resulting in increased visual fatigue and the degradation of diagnostic performance. A controlled increase of ambient lighting may, however, minimize these visual adjustments and potentially improve reader comfort and accuracy. This paper details results from two psychophysical studies designed to determine the effect of a controlled ambient lighting increase on observer detection of subtle objects and lesions viewed on a DICOM-calibrated medical-grade LCD. The first study examined the effect of increased ambient lighting on detection of subtle objects embedded within a uniform background, while the second study examined observer detection performance of subtle cancerous lesions in mammograms and chest radiographs. In both studies, observers were presented with images under a dark room condition (1 lux) and an increased room illuminance level (50 lux) for which the luminance level of the diffusely reflected light from the background wall was approximately equal to that of the displayed image. The display was calibrated to an effective luminance ratio of 409 for both lighting conditions. Observer detection performance under each room illuminance condition was then compared. Identification of subtle objects embedded within the uniform background improved from 59% to 67%, while detection time decreased slightly with additional illuminance. An ROC analysis of the anatomical image results revealed that observer AUC values remained constant while detection time decreased under increased illuminance. The results provide evidence that an ambient lighting increase may be possible without compromising diagnostic efficacy.

  6. 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.

  7. [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.

  8. Interpreting the effects of altered brain anatomical connectivity on fMRI functional connectivity: a role for computational neural modeling.

    Science.gov (United States)

    Horwitz, Barry; Hwang, Chuhern; Alstott, Jeff

    2013-01-01

    Recently, there have been a large number of studies using resting state fMRI to characterize abnormal brain connectivity in patients with a variety of neurological, psychiatric, and developmental disorders. However, interpreting what the differences in resting state fMRI functional connectivity (rsfMRI-FC) actually reflect in terms of the underlying neural pathology has proved to be elusive because of the complexity of brain anatomical connectivity. The same is the case for task-based fMRI studies. In the last few years, several groups have used large-scale neural modeling to help provide some insight into the relationship between brain anatomical connectivity and the corresponding patterns of fMRI-FC. In this paper we review several efforts at using large-scale neural modeling to investigate the relationship between structural connectivity and functional/effective connectivity to determine how alterations in structural connectivity are manifested in altered patterns of functional/effective connectivity. Because the alterations made in the anatomical connectivity between specific brain regions in the model are known in detail, one can use the results of these simulations to determine the corresponding alterations in rsfMRI-FC. Many of these simulation studies found that structural connectivity changes do not necessarily result in matching changes in functional/effective connectivity in the areas of structural modification. Often, it was observed that increases in functional/effective connectivity in the altered brain did not necessarily correspond to increases in the strength of the anatomical connection weights. Note that increases in rsfMRI-FC in patients have been interpreted in some cases as resulting from neural plasticity. These results suggest that this interpretation can be mistaken. The relevance of these simulation findings to the use of functional/effective fMRI connectivity as biomarkers for brain disorders is also discussed.

  9. 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

  10. 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.

  11. 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.

  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. Laparoscopic Cryoablation Of Small Renal Tumors – Does Anatomical Tumor Complexity Effect Treatment Outcome?

    DEFF Research Database (Denmark)

    Nielsen, Tommy Kjærgaard; Østraat, Øyvind; Andersen, Gratien;

    status: 1.2 (95%CI 1.0;1.3). Mean tumor size: 27 mm (95%CI 26;29). Mean follow-up time: 24 months (95%CI 20;27). A total of 16 patients (13%) were previously diagnosed with renal cancer and the majority of these patients had previously undergone nephrectomy. PADUA-score was found to be low or moderate......Background: Renal cryoablation is a valid treatment option for localized pT1a renal tumors and has been the modality of choice at Aarhus University Hospital since 2005. Anatomical tumor classification systems such as PADUA and RENAL scores were initially introduced as tools to evaluate complication...... compared to patients with a less anatomical complex tumor when treated with laparoscopic cryoablation. Material and methods: A retrospective review of Aarhus Cryoablation Register identified 120 patients with a single biopsy-verified pT1a renal tumor, treated with primary laparoscopic cryoablation between...

  14. Effect of head shape variations among individuals on the EEG/MEG forward and inverse problems.

    Science.gov (United States)

    von Ellenrieder, Nicolás; Muravchik, Carlos H; Wagner, Michael; Nehorai, Arye

    2009-03-01

    We study the effect of the head shape variations on the EEG/magnetoencephalography (MEG) forward and inverse problems. We build a random head model such that each sample represents the head shape of a different individual and solve the forward problem assuming this random head model, using a polynomial chaos expansion. The random solution of the forward problem is then used to quantify the effect of the geometry when the inverse problem is solved with a standard head model. The results derived with this approach are valid for a continuous family of head models, rather than just for a set of cases. The random model consists of three random surfaces that define layers of different electric conductivity, and we built an example based on a set of 30 deterministic models from adults. Our results show that for a dipolar source model, the effect of the head shape variations on the EEG/MEG inverse problem due to the random head model is slightly larger than the effect of the electronic noise present in the sensors. The variations in the EEG inverse problem solutions are due to the variations in the shape of the volume conductor, while the variations in the MEG inverse problem solutions, larger than the EEG ones, are caused mainly by the variations of the absolute position of the sources in a coordinate system based on anatomical landmarks, in which the magnetometers have a fixed position.

  15. 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

  16. Diagnosis and Management of Anatomic Variations of the Cystic Duct during Laparoscopic Cholecystectomy%腹腔镜胆囊切除术中胆囊管解剖变异的诊断及处理

    Institute of Scientific and Technical Information of China (English)

    龚解其; 严斌; 陈伟新; 沈卫星

    2014-01-01

    Objective:To explore the diagnosis and management of anatomic variation of the cystic duct during laparoscopic cholecystectomy(LC) .Methods :From Jan 1999 to Dec 2013 ,4652 cases of LC ,which were performed in Qingpu Branch of Zhongshan Hospital ,Fudan University ,were retrospectively analyzed .A total of 34 cases of anatomic variation of the cystic duct were found .Among the 34 cases of anatomic variation of the cystic duct ,11 cases had thick and short cystic duct ,7 cases had a cystic duct converged into right hepatic duct ,6 cases had cystic duct converged into lower part of common hepatic duct ,1 case had cystic duct pronated forward and converged into common hepatic duct from left side ,3 cases had cystic duct that paral-lel itself with common hepatic duct and then converged into common bile duct ,4 cases were diagnosed with Mrizzi syndrome ,2 cases had situs viscera inversus .Results:Among the 34 cases with anatomic variations of cystic duct ,22 cases successfully un-derwent LC ,the other 12 cases were converted to open cholecystectomy .All the complications were biliary duct injury that re-covered well after treatment .Conclusions :Anatomic variation of the cystic duct is hard to diagnose preoperatively .Paying More attention to the anatomic variation during LC ,dissecting calot′s triangle carefully ,and identifying the relationship between the various pipeline is the key to prevent and reduce the biliary duct injury .%目的:探讨腹腔镜胆囊切除术(laparoscopic cholecystectomy ,LC )中胆囊管解剖变异的诊断及处理。方法:回顾分析1999年1月-2013年12月在复旦大学附属中山医院青浦分院行LC的4652例患者的临床资料,其中胆囊管发生解剖变异者34例,包括胆囊管异常粗、短11例,高位汇入右肝管7例,低位汇入肝总管下端6例,从肝总管前方绕至左侧汇入肝总管1例,与肝总管并行一段后汇入胆总管3例,M rizzi综合征4例,内脏反位2

  17. Validation of semi-quantitative methods for DAT SPECT: influence of anatomical variability and partial volume effect

    Science.gov (United States)

    Gallego, J.; Niñerola-Baizán, A.; Cot, A.; Aguiar, P.; Crespo, C.; Falcón, C.; Lomeña, F.; Sempau, J.; Pavía, J.; Ros, D.

    2015-08-01

    The aim of this work was to evaluate the influence of anatomical variability between subjects and of the partial volume effect (PVE) on the standardized Specific Uptake Ratio (SUR) in [123I]FP-bib SPECT studies. To this end, magnetic resonance (MR) images of 23 subjects with differences in the striatal volume of up to 44% were segmented and used to generate a database of 138 Monte Carlo simulated SPECT studies. Data included normal uptakes and pathological cases. Studies were reconstructed by filtered back projection (FBP) and the ordered-subset expectation-maximization algorithm. Quantification was carried out by applying a reference method based on regions of interest (ROIs) derived from the MR images and ROIs derived from the Automated Anatomical Labelling map. Our results showed that, regardless of anatomical variability, the relationship between calculated and true SUR values for caudate and putamen could be described by a multiple linear model which took into account the spill-over phenomenon caused by PVE ({{R}2}≥slant 0.963 for caudate and ≥0.980 for putamen) and also by a simple linear model (R2 ≥ 0.952 for caudate and ≥0.973 for putamen). Calculated values were standardized by inverting both linear systems. Differences between standardized and true values showed that, although the multiple linear model was the best approach in terms of variability ({χ2}  ≥ 11.79 for caudate and  ≤7.36 for putamen), standardization based on a simple linear model was also suitable ({χ2}  ≥ 12.44 for caudate and  ≤12.57 for putamen).

  18. 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.

  19. 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

  20. 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.

  1. 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.

  2. Effect of positional changes of anatomic structures on upper airway dilating muscle shortening during electro- and chemostimulation.

    Science.gov (United States)

    Oliven, A; Odeh, M

    2006-09-01

    Positional changes of anatomic structures surrounding the upper airway are known to affect pharyngeal mechanics and collapsibility. We hypothesized that these alterations also affect the ability of the upper airway dilator muscles to enlarge the pharynx by altering their ability to shorten when activated. Using sonomicrometry, we evaluated in seven anesthetized dogs the effects of changes in tracheal and head position on the length of the genioglossus (GG) and the geniohyoid (GH) and the effects of these positional changes on the magnitude of shortening of the two muscles in response to electro- (ES) and chemostimulation (CS). Caudal traction of the trachea lengthened the GG and GH in all dogs, whereas cranial displacement of the trachea and flexion of the head to a vertical position shortened the muscles. Compared with the magnitude of ES-induced shortening in the neutral position, ES-induced shortening of the GG was 144.7 +/- 14.6, 49.3 +/- 4.3, and 33.5 +/- 11.6% during caudal and cranial displacement of the trachea and during head flexion, respectively. Similar effects of the positional changes were found for the GH, as well as for both muscles during respiratory stimulation with P(CO2) of 90 Torr at the end of CO(2) rebreathing, although inspiratory muscle shortening during CS reached only one-quarter to one-third of the magnitude observed during ES. We conclude that positional alterations of anatomic structures in the neck have a dramatic effect on the magnitude of shortening of the activated GG and GH, which may reduce substantially their ability to protect pharyngeal patency.

  3. Variation of Photosynthesis, Fatty Acid Composition, ATPase and Acid Phosphatase Activities, and Anatomical Structure of Two Tea (Camellia sinensis (L. O. Kuntze Cultivars in Response to Fluoride

    Directory of Open Access Journals (Sweden)

    L. X. Wang

    2013-01-01

    Full Text Available The changes of photosynthetic parameters, water use efficiency (WUE, fatty acid composition, chlorophyll (Chl content, malondialdehyde (MDA content, ATPase and acid phosphatase activities, fluoride (F content, and leaf anatomical structure of two tea cultivars, “Pingyangtezao” (PY and “Fudingdabai” (FD, after F treatments were investigated. The results show that net photosynthetic rate (, stomatal conductance (, and transpiration rate (E significantly decreased in both cultivars after 0.3 mM F treatment, but FD had higher , , and WUE and lower E than PY. Chl content in PY significantly decreased after 0.2 and 0.3 mM F treatments, while no significant changes were observed in FD. The proportions of shorter chain and saturated fatty acids increased and those of longer chain and unsaturated fatty acids decreased in both cultivars under F treatments. The contents of MDA increased after F treatments but were higher in PY than in FD. In addition, F treatments decreased the activities of ATPase and acid phosphatase and increased F content in both cultivars; however, compared with PY, FD showed higher enzymatic activities and lower F content in roots and leaves. Leaf anatomical structure in FD indicated that cells in leaf midrib region were less injured by F than in PY.

  4. Researching the effect of the practical applications performed with cadaver dissection and anatomical models on anatomy education

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    Vedat Sabancıoğulları

    2016-12-01

    Full Text Available Objective: The most important element in providing good quality of healthcare is well training of healthcare staff, particularly doctors. The way of being a good and successful healthcare staff is to learn the human anatomy accurately and permanently. Practical applications as well as theoretical courses are also highly important in learning human anatomy. In classical anatomy education, using cadaver is accepted to be indispensable. However, along with the new medical faculties, there has been an increase in the shortage of cadaver, and anatomy practices have mainly begun to be carried out on models or mock-ups. Therefore, we aimed to study with anatomic models in practical applications and to research the effect of cadaver dissection on learning anatomy. Method: In this study including 120-second grade students that their achievement levels are close together and participating in the theoretical courses of anatomy in medical faculty during 2015 – 2016 academic year. To realize this, students were divided into four groups (1st group were include students only listening to theoretical course, 2nd group theoretical course and performing application with anatomic models, 3rd group theoretical course and performing application with cadaver dissection, and 4th group theoretical course and performing application with anatomic models and cadaver dissection of 30 people. Degree of students’ understanding the subject was detected with written and practical exams consists of 10 questions after the theoretical and practical courses on each committee. The resulting data are loaded to SPSS 22.0 software and statistical evaluation One-way ANOVA, Mann-Whitney, chi-square test was used. Results: The average of students who practice on both models and cadavers were statistically significant (p 0.05. Conclusions: The results obtained from our study indicate that anatomy practical training is carried out with the dissection of cadavers that made it easier to

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

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    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.

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

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    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.

  7. Violation of Dollo's law: evidence of muscle reversions in primate phylogeny and their implications for the understanding of the ontogeny, evolution, and anatomical variations of modern humans.

    Science.gov (United States)

    Diogo, Rui; Wood, Bernard

    2012-10-01

    According to Dollo's law, once a complex structure is lost it is unlikely to be reacquired. In this article, we report new data obtained from our myology-based cladistic analyses of primate phylogeny, which provide evidence of anatomical reversions violating Dollo's law: of the 220 character state changes unambiguously optimized in the most parsimonious primate tree, 28 (13%) are evolutionary reversions, and of these 28 reversions six (21%) occurred in the nodes that lead to the origin of modern humans; nine (32%) violate Dollo's law. In some of these nine cases, the structures that were lost in adults of the last common ancestor and are absent in adults of most subgroups of a clade are actually present in early ontogenetic stages of karyotypically normal individuals as well as in later ontogenetic stages of karyotypically abnormal members of those subgroups. Violations of Dollo's law may thus result from the maintenance of ancestral developmental pathways during long periods of trait absence preceding the reacquisition of the trait through paedomorphic events. For instance, the presence of contrahentes and intermetacarpales in adult chimpanzees is likely due to a prolonged/delayed development of the hand musculature, that is, in this case chimpanzees are more neotenic than modern humans.

  8. 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)

  9. 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

  10. 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

  11. 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.

  12. 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.

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

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    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.

  14. Physiological, anatomical, biochemical, and cytogenetic effects of thiamethoxam treatment on Allium cepa (amaryllidaceae) L.

    Science.gov (United States)

    Çavuşoğlu, Kültiğin; Yalçin, Emine; Türkmen, Zafer; Yapar, Kürşad; Sağir, Saffet

    2012-11-01

    In the present study, toxic effects of active substance thiamethoxam of the insecticide Eforia were investigated on Allium cepa L. For this aim, we used the germination percentage, root length, weight gain, malondialdehyde (MDA) level, frequency of micronucleus (MN), chromosomal aberrations (CAs), and mitotic index (MI) as indicators of toxicity. Also, the changes in the root anatomy of A. cepa seeds treated with thiamethoxam were examined. The seeds in all the treatment groups were treated with three different doses (100, 250, and 500 mg/kg) of thiamethoxam for 72 h. The results showed that there were significant alterations in the germination percentage, root length, weight gain, MDA level, MN, CAs, and MI frequency depending on application dose in the seeds exposed to thiamethoxam compared to control group. Thiamethoxam treatments significantly reduced the germination percentage, root length, and weight gain in all the treatment groups (P thiamethoxam has a mito-depressive action on mitosis, and the MI was decreased depending on the dose of applied-thiamethoxam (P thiamethoxam significantly enhanced the lipid peroxidation and caused an increase in MDA levels at each dose treatment (P thiamethoxam caused severe toxic effects on A. cepa cells, and the maximum toxic effect was observed at the dose level of 500 mg/kg.

  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. 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.

  17. 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.

  18. 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.

  19. Effect of different levels of physical activity upon anatomical and histologic changes related to renal aging

    Directory of Open Access Journals (Sweden)

    Benjamin Wancjer, MD

    2003-12-01

    Full Text Available Title: Effects of Different Grades of PhysicalActivity in the Presentation of Anathomic andHistologic Changes Related with Renal Aging.Objective:With the purpose of determininganatomical changes of exercise in renal aging.Methodology: we carried out an experimentallongitudinal study during 54 weeks. 120 swiss malemice were used, which were divided into threegroups depending on their activity: sedentary,normal and active. The exercise was modulatedwith room space and food acces. three animals weresacrificed per group from the ninth week of age,each nine weeks. All animals with less than 27weeks of age were considered young animals, andold animals were more than 36 weeks old. all miceand kidneys were weighted, establishing a kidneyweight/mouse weight relation. The cortex of eachanimal´s left kidney was measured. And ahistological estudy with classical colorations wascarried out. Such cuts were analyzed by 2pathologist who did not know the purpose of thisstudy; they described glomerular changes andinterstitial tubulus, classifying them from null tosevere. Glomerular areas, as well as light/arterialwall relation were measured. Results: maximum renal growing was detected 18 weeks later. At the54th week, the sedentary mice had less corticalthickness (2288,65 ± 552,75 than the animals ofthe normal group (2502,7 ± 163,81 and the activegroup (2609,46 ± 273,28, with n=3 for allgroups. The glomerular area was significantly less(p=0,035 in sedentary animals (8657,33 ±1954,38 compared to the active animals(10318,64 ± 2425,14, but significant differenceswere not found among the normal animals(9791,52 ± 2211,63 and the other to groups,n=18 for each group. tubular atrophy in oldanimals was 55,5% in sedentary animals, higherthan in normal and active animals, in which itwas 44,4%, not significant. Interstitial nephritiswas less in normal animals (55,5% compared tosedentary and active groups (77,7%, notsignificant. Conclusions: We could conclede thatthe

  20. 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.

  1. 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…

  2. Variational Calculation of the Effective Action

    CERN Document Server

    Sugihara, T

    1998-01-01

    An indication of spontaneous symmetry breaking is found in the two-dimensional $\\lambda\\phi^4$ model, where an attention is payed to a functional form of an effective action. An effective energy, which is an effective action for a static field, is obtained as a functional of the classical field from the ground state of hamiltonian $H[J]$ interacting with a constant external field. The energy and wavefunction of the ground state are calculated in terms of DLCQ (Discretized Light-Cone Quantization) under antiperiodic boundary condition. A field configuration which is physically meaningful is found as a solution of the quantum mechanical Euler-Lagrange equation in the $J\\to 0$ limit. It is shown that there exists a nontrivial field configuration in the broken phase of $Z_2$ symmetry because of a boundary effect.

  3. 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

  4. 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...

  5. Modeling the effects of developmental variation on insect phenology.

    Science.gov (United States)

    Yurk, Brian P; Powell, James A

    2010-08-01

    Phenology, the timing of developmental events such as oviposition or pupation, is highly dependent on temperature; since insects are ectotherms, the time it takes them to complete a life stage (development time) depends on the temperatures they experience. This dependence varies within and between populations due to variation among individuals that is fixed within a life stage (giving rise to what we call persistent variation) and variation from random effects within a life stage (giving rise to what we call random variation). It is important to understand how both types of variation affect phenology if we are to predict the effects of climate change on insect populations.We present three nested phenology models incorporating increasing levels of variation. First, we derive an advection equation to describe the temperature-dependent development of a population with no variation in development time. This model is extended to incorporate persistent variation by introducing a developmental phenotype that varies within a population, yielding a phenotype-dependent advection equation. This is further extended by including a diffusion term describing random variation in a phenotype-dependent Fokker-Planck development equation. These models are also novel because they are formulated in terms of development time rather than developmental rate; development time can be measured directly in the laboratory, whereas developmental rate is calculated by transforming laboratory data. We fit the phenology models to development time data for mountain pine beetles (MPB) (Dendroctonus ponderosae Hopkins [Coleoptera: Scolytidae]) held at constant temperatures in laboratory experiments. The nested models are parameterized using a maximum likelihood approach. The results of the parameterization show that the phenotype-dependent advection model provides the best fit to laboratory data, suggesting that MPB phenology may be adequately described in terms of persistent variation alone. MPB

  6. 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

  7. Variações anatômicas na dentição de cães sem raça definida Anatomical variations in the dentition of mongrel domestic dogs

    Directory of Open Access Journals (Sweden)

    Moacir Santos de Lacerda

    2000-08-01

    Full Text Available Foi avaliada a dentição de 100 cães adultos sem raça definida, machos e fêmeas, com o objetivo de investigar as variações anatômicas. A ausência congênita de molares foi observada em cães de pequeno porte; a ausência patológica predominou na região dos pré-molares; houve maior frequência de dentes supranumerários na arcada superior, predominando os molares; foram observadas raízes supranumerárias em pré-molares e molares superiores e inferiores; e grande número de raízes fusionadas, predominando no segundo pré-molar inferior.The dentition of 100 adult males and females mongrel dogs were analysed with lhe objective of investigating the anatomical variations in the dentition. The congenital absence of molars teeth was observed in small dogs. The pathologic absence prevailed in the premolars area. Supemumerary teeth, mainly the molars, were observed in the maxillary arcade. Supemumerary roots on the upper and lower premolars and molars teeth were observed. A large number of fused roots were observed, mainly in the mandibular second premolar teeth.

  8. 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.

  9. 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

  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. Wood anatomical classification using iterative character weighing

    NARCIS (Netherlands)

    Hogeweg, P.; Koek-Noorman, J.

    1975-01-01

    In this paper we investigate the pattern of wood anatomical variation in some groups of Rubiaceae (i.e. Cinchoneae, Rondeletieae and Condamineae) by using a numerical pattern detection method which involves character weighing (Hogeweg 1975). In this method character weights are obtained iteratively

  12. The effect of model errors in variational assimilation

    Science.gov (United States)

    Wergen, Werner

    1992-08-01

    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 assimilation with the model used as strong constraint is shown to distribute the model errors over the entire analysis domain. The implications for verification and diagnostics are discussed. Temporal weighting of the observations can reduce the errors towards the end of the assimilation period, but may deteriorate the subsequent forecasts. An extension to variational assimilation is proposed, which seeks not only to determine the initial state from the observations but also some of the tunable parameters of the model. The potentional usefulness of this approach for parameterization studies and for a separation of forecast errors into model- and analysis errors is discussed. Finally, variational assimilations with the model used as weak constraint are presented. While showing a good performance in the assimilation, forecasts can suffer severely if the extra term in the equations up to which the model is enforced are unable to compensate for the real model error. In the discussion, an overall appraisal of both assimilation methods is given.

  13. The anatomical variations and surgical treatment of congenital coarctation of aorta in children%儿童先天性主动脉缩窄的解剖特点及外科治疗策略

    Institute of Scientific and Technical Information of China (English)

    武开宏; 孙剑; 莫绪明; 彭卫; 戚继荣; 张玉喜; 庄著伦

    2016-01-01

    Objective To investigate the anatomical variations and surgical treatment of congenital coarctation of aorta in children. Methods From May 2012 to Jun 2014, 30 patients (male 22, female 8) between the ages of 12 days to 6 years with congenital coarctation of aorta who received surgical treatment in department of Cardiothoracic Surgery of Nanjing Children' s Hospital were reviewed. According to the international classification criteria for Pediatric Cardiac Surgery Nomenclature, anatomical variations included simple type coarctation (12 patients), coarctation with ventricular septal defect ( VSD, 8 patients), coarctation with complex congenital heart disease (5 patients), coarctation with hypoplasia of aortic arch (5 patients). Among the total 30 patients, 20 patients were performed under cardiopulmonary bypass and 8 with the assistance of selective cerebral perfusion, 10 patients were performed without cardiopulmonary bypass, included 2 patients which were carried out through median sternotomy (1 with hybrid occlusion of muscular VSD) and the other 8 patients which were done through left thoracic incision. Results All the patients received the surgical correction of coarctation of aorta and associated cardiac anomalies successfully, surgical duration from 95 to 675 min, mean 165. 68 min, 2 patients were dead in this group. One patient was reoperated (surgical sling) because of his high peak airway pressure and being difficult to wean from mechanical ventilation, and he was successfully weaned from respirator and discharged from hospital after reoperation. All the other patients recovered uneventfully and discharged from hospital after recovery. Follow up (0. 5 - 2 years) information of 28 survived patients showed 1 patient with restenosis was found, whose pressure difference between upper/ lower limbs was 50 mmHg(1 mmHg = 0. 133 kPa) and he was still under close follow up, the other patients had normal growth and development, whose pressure difference between upper

  14. 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.

  15. Synaptic channel model including effects of spike width variation

    OpenAIRE

    2015-01-01

    Synaptic Channel Model Including Effects of Spike Width Variation Hamideh Ramezani Next-generation and Wireless Communications Laboratory (NWCL) Department of Electrical and Electronics Engineering Koc University, Istanbul, Turkey Ozgur B. Akan Next-generation and Wireless Communications Laboratory (NWCL) Department of Electrical and Electronics Engineering Koc University, Istanbul, Turkey ABSTRACT An accu...

  16. Three dimensional printing as an effective method of producing anatomically accurate models for studies in thermal ecology.

    Science.gov (United States)

    Watson, Charles M; Francis, Gamal R

    2015-07-01

    Hollow copper models painted to match the reflectance of the animal subject are standard in thermal ecology research. While the copper electroplating process results in accurate models, it is relatively time consuming, uses caustic chemicals, and the models are often anatomically imprecise. Although the decreasing cost of 3D printing can potentially allow the reproduction of highly accurate models, the thermal performance of 3D printed models has not been evaluated. We compared the cost, accuracy, and performance of both copper and 3D printed lizard models and found that the performance of the models were statistically identical in both open and closed habitats. We also find that 3D models are more standard, lighter, durable, and inexpensive, than the copper electroformed models.

  17. Ecophysiological and Anatomical Mechanisms behind the Nurse Effect: Which Are More Important? A Multivariate Approach for Cactus Seedlings

    Science.gov (United States)

    Delgado-Sánchez, Pablo; Yáñez-Espinosa, Laura; Jiménez-Bremont, Juan Francisco; Chapa-Vargas, Leonardo; Flores, Joel

    2013-01-01

    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. PMID:24312310

  18. Variação das dimensões dos elementos anatômicos da madeira de árvores de Eucalyptus grandis Hill ex Maiden aos sete anos. Variation of anatomical structure of wood of Eucalyptus grandis Hill ex Maiden with 7 years old.

    Directory of Open Access Journals (Sweden)

    Finê Thomaz ROCHA

    2004-06-01

    Full Text Available A variação das dimensões dos elementos anatômicos do lenho tem um efeito marcante sobre a qualidade da madeira e o produto final. Visando obter melhores informações sobre o assunto, foram coletadas amostras de árvores dominantes, intermediárias e dominadas de Eucalyptus grandis aos sete anos, com o objetivo de verificar as variações das dimensões dos elementos anatômicos entre árvores, no sentido medula-casca e base-topo. De cada árvore foram retirados discos de madeira na base, 25, 50, 75 e 100% da altura comercial. Em cada disco foram demarcados corpos de prova a 0, 50 e 100% do raio. Os elementos anatômicos foram mensurados através de programa de análise de imagens. Os resultados permitem concluir que: (a das classes sociológicas, a dominante apresentou fibras 14% mais longas e 20% mais espessas, diâmetro de vasos 30% mais largo e raios 20% mais altos do que as outras classes; (b os maiores valores das dimensões das fibras e comprimento de vasos foram encontrados a 25% da altura comercial, os vasos apresentaram-se mais largos a 75% e a freqüência de raios foi maior no topo, e (c em todas as dimensões das fibras, o diâmetro e o comprimento dos vasos foram crescentes.The variation in the dimensions of the anatomical elements of the xylem has a marked effect on the quality of wood and on the final product. In order to obtain further information about this variation samples of dominant, intermediate and dominated 7-year-old Eucalyptus grandis trees were collected. The aim was to analyze the variation in the dimensions of the anatomical elements among trees in the pith-bark and base-top directions. Wood disks from the base, 25, 50, 75 and 100% of the commercial height were removed from each tree. From each disk samples at 0, 50 and 100% of the radius were defined. The anatomical elements were measured through image analysis. The results indicate that: (a of all sociological classes, the dominant one showed fibers 14% longer

  19. 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

  20. 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.

  1. The effect of temperature variation on biomethanation at high altitude.

    Science.gov (United States)

    Alvarez, René; Lidén, Gunnar

    2008-10-01

    The aim of the current study was to examine effects of daily temperature variations on the performance of anaerobic digestion. Forced square-wave temperature variations (between 11 and 25, 15 and 28, and 19 and 32 degrees C) were imposed on a bench-scale digester using a mixture of llama-cow-sheep manure in a semi-continuous process. The volumetric biogas production rate, methane yield, and the volatile solid reductions were compared with the results obtained from anaerobic digestion (AD) at constant temperatures. The forced cyclic variations of temperature caused large cyclic variations in the rate of gas production and the methane content. As much as 94-97% of the daily biogas was obtained in the 12h half-cycle at high temperature. The values for volumetric biogas production rate and methane yield increased at higher temperatures. The average volumetric biogas production rate for cyclic operation between 11 and 25 degrees C was 0.22Ld(-1)L(-1) with a yield of 0.07m3CH4kg(-1) VS added (VSadd), whereas for operation between 15 and 29 degrees C the volumetric biogas production rate increased by 25% (to 0.27Ld(-1)L(-1) with a yield of 0.08m3CH4kg(-1) VSadd). In the highest temperature region a further increase of 7% in biogas production was found and the methane yield was 0.089m(3)CH(4)kg(-1) VSadd. The employed digester showed an immediate response when the temperature was elevated, which indicates a well-maintained metabolic capacity of the methanogenic bacteria during the period of low temperature. Overall, periodic temperature variations appear to give less decrease in process performance than a priori anticipated.

  2. Effects of brain-stem and thalamic lesions on the corneal reflex: an electrophysiological and anatomical study.

    Science.gov (United States)

    Ongerboer de Visser, B W; Moffie, D

    1979-09-01

    In 9 patients with Wallenberg's lateral medullary syndrome, one patient with a midbrain lesion involving the right side of the tegmentum, and 2 patients with a thalamic lesion, corneal reflexes were investigated by a new electromyographic technique. The electrophysical results were compared with the results obtained by clinical observation. In the lateral medullary lesions the electrophysiologically obtained reflex responses showed four types of abnormality. Type A consisted of a bilateral delay and type B a bilateral absence of the corneal reflex response to stimulation on the affected side in combination with a normal reflex response on both sides when the cornea on the normal side was stimulated. Type C, which was present in one case, and type D which was seen in 3 cases, consisted of a bilateral absence of the corneal reflex upon stimulation on the affected side; stimulation on the unaffected side produced a normal reflex response on the intact side in combination with, respectively, a delay or absence of the corneal reflex response on the affected side. Comparison of the clinical observations with the electrophysiological findings revealed minor discrepancies in type A and B abnormalities. However, the electrophysiological type C and D abnormalities were not detected by clinical observation. These findings demonstrate that electrophysiological recording of the corneal reflex may reveal clinically undetectable abnormalities. From the electrophysiological findings it is concluded that the corneal reflex is conducted along medullary pathways running both ipsilaterally and contralaterally from the stimulated side before connecting, respectively, with the ipsilateral and contralateral facial nucleus. From the anatomical findings it is suggested that the ascending pathways from the spinal fifth nerve complex to the facial nuclei are located in the lateral reticular formation of the lower brain-stem. The normal corneal reflex responses in the presence of thalamic and

  3. 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.

  4. 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.

  5. SimUVEx v2 : a numeric tool to predict anatomical solar ultraviolet exposure

    OpenAIRE

    2016-01-01

    Solar ultraviolet (UV) radiation has a dual effect on human health: low UV doses promote the photosynthesis of vitamin D and regulate calcium and phosphorus metabolism, while an excessive UV exposure is the main cause of skin cancer, along with eye diseases and premature skin ageing. The link between UV radiation levels and UV exposure is not fully understood since exposure data are limited and individual anatomical variations in UV doses are significant. SimUVEx is a numeric simulation tool ...

  6. 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.)

  7. Anatomical variations in the human sinuatrial nodal artery As variações de número, origem e trajeto do ramo do nó sinoatrial em corações humanos

    Directory of Open Access Journals (Sweden)

    José Roberto Ortale

    2006-01-01

    Full Text Available OBJECTIVE: To analyze the anatomical variations of sinuatrial nodal branch(es of the coronary artery mainly regarding their number; a recent report from Japan claims the presence of 2 branches in up to 50% of cases, an occurrence that would permit adequate flow compensation in case of occlusion or section of 1 of these branches. METHODS: The sinuatrial nodal branch(es of 50 human hearts fixed in formol solution were dissected with the aid of a Normo Health 3.0 degree visor magnifying lens, measured, and classified as to the origin, route, and number of branches. RESULTS: In 94% (n = 47 of cases, a single sinuatrial nodal branch was found. classified: (A two right side types, R1 (in 46% of cases, n = 23, situated medial to the right auricle and R2 (in 4% of cases, n = 2, situated on the posterior surface of the right atrium; (B three left side types, L1 (in 24% of cases, n = 12, situated medial to the left auricle, L2 (in 16% of cases, n = 8, situated posterior to the left auricle, and L3 (in 4% of cases, n = 2, situated on the posterior surface of the left atrium. Except for R2, each type was subdivided into 'a' or 'b' types, according to whether the sinuatrial nodal branch(es occurred in a clockwise or counterclockwise orientation around the base of the superior cava vena. In 4% of cases (n = 2, 2 sinuatrial nodal branch(es were observed with 1 branch originating from each of the coronary arteries. In 1 case (2%, 3 sinuatrial nodal branch(es were found, 2 from the right coronary artery and the third probably from the bronchial branch of the thoracic aorta. In 30% of the cases, the sinuatrial nodal branch(es formed a ring around the base of the superior cava vena. In all cases, the sinuatrial nodal branch(es supplied collateral branches to the atrium and/or the auricle of the same side as its origin and/or to the opposite side. CONCLUSION: The low frequency of 2 sinuatrial nodal branch(es in Brazilian individuals, compared to the higher

  8. 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.

  9. A veterinary digital anatomical database.

    Science.gov (United States)

    Snell, J R; Green, R; Stott, G; Van Baerle, S

    1991-01-01

    This paper describes the Veterinary Digital Anatomical Database Project. The purpose of the project is to investigate the construction and use of digitally stored anatomical models. We will be discussing the overall project goals and the results to date. Digital anatomical models are 3 dimensional, solid model representations of normal anatomy. The digital representations are electronically stored and can be manipulated and displayed on a computer graphics workstation. A digital database of anatomical structures can be used in conjunction with gross dissection in teaching normal anatomy to first year students in the professional curriculum. The computer model gives students the opportunity to "discover" relationships between anatomical structures that may have been destroyed or may not be obvious in the gross dissection. By using a digital database, the student will have the ability to view and manipulate anatomical structures in ways that are not available through interactive video disk (IVD). IVD constrains the student to preselected views and sections stored on the disk.

  10. The effect of variation in naturalness on phonetic perceptual identification

    Science.gov (United States)

    Remez, Robert E.; Yang, Cynthia Y.; Piorkowski, Rebecca L.; Wissig, Stephanie; Batchelder, Abigail; Nam, Heddy

    2002-05-01

    The relation between apparent naturalness and phonetic identification was assessed in six perceptual tests. A seven-step place-of-articulation series spanning [da] to [ga] was created with speech synthesis approximating the spectra of natural samples. The sensitivity of perceivers to this realization of a place contrast was assessed by estimating the cumulative d' across the series in identification tests. Four variants of this series differing in apparent naturalness were produced by altering the synthesis source function while preserving the center frequency and bandwidth of the formants, and by replicating the gross spectrotemporal patterns with time-varying sinusoids. In addition to calibrating perceivers' sensitivity to the place contrast over variation in naturalness, we conducted a naturalness tournament composed of items drawn from the five test series. A correlation of the findings of the naturalness tournament with the measures of phonetic sensitivity offers an index of the effect of variation in naturalness on phonetic perception. This study can resolve the dispute between the classic premise that intelligibility and naturalness are orthogonal attributes of speech perception, and the more recent premise entailed by episodically based accounts of perceptual categorization, that novel instances are identified by virtue of auditory similarity to prior exemplars. [Research supported by NIDCD.

  11. Orbital effects of spatial variations of fundamental coupling constants

    CERN Document Server

    Iorio, Lorenzo

    2011-01-01

    We deal with the effects induced on the orbit of a test particle revolving around a central body by putative spatial variations of fundamental coupling constants $\\zeta$. In particular, we assume a dipole gradient for $\\zeta(\\bds r)/\\bar{\\zeta}$ along a generic direction $\\bds{\\hat{k}}$ in space. We analytically work out the long-term variations of all the six standard Keplerian orbital elements parameterizing the orbit of a test particle in a gravitationally bound two-body system. It turns out that, apart from the semi-major axis $a$, the eccentricity $e$, the inclination $I$, the longitude of the ascending node $\\Omega$, the longitude of pericenter $\\pi$ and the mean anomaly $\\mathcal{M}$ undergo non-zero long-term changes. By using the usual decomposition along the radial ($R$), transverse ($T$) and normal ($N$) directions, we also analytically work out the long-term changes $\\Delta R,\\Delta T,\\Delta N$ and $\\Delta v_R,\\Delta v_T,\\Delta v_N$ experienced by the position and the velocity vectors $\\bds r$ and...

  12. A veterinary digital anatomical database.

    OpenAIRE

    Snell, J.R.; Green, R; Stott, G; Van Baerle, S.

    1991-01-01

    This paper describes the Veterinary Digital Anatomical Database Project. The purpose of the project is to investigate the construction and use of digitally stored anatomical models. We will be discussing the overall project goals and the results to date. Digital anatomical models are 3 dimensional, solid model representations of normal anatomy. The digital representations are electronically stored and can be manipulated and displayed on a computer graphics workstation. A digital database of a...

  13. Occipital neuralgia: anatomic considerations.

    Science.gov (United States)

    Cesmebasi, Alper; Muhleman, Mitchel A; Hulsberg, Paul; Gielecki, Jerzy; Matusz, Petru; Tubbs, R Shane; Loukas, Marios

    2015-01-01

    Occipital neuralgia is a debilitating disorder first described in 1821 as recurrent headaches localized in the occipital region. Other symptoms that have been associated with this condition include paroxysmal burning and aching pain in the distribution of the greater, lesser, or third occipital nerves. Several etiologies have been identified in the cause of occipital neuralgia and include, but are not limited to, trauma, fibrositis, myositis, fracture of the atlas, and compression of the C-2 nerve root, C1-2 arthrosis syndrome, atlantoaxial lateral mass osteoarthritis, hypertrophic cervical pachymeningitis, cervical cord tumor, Chiari malformation, and neurosyphilis. The management of occipital neuralgia can include conservative approaches and/or surgical interventions. Occipital neuralgia is a multifactorial problem where multiple anatomic areas/structures may be involved with this pathology. A review of these etiologies may provide guidance in better understanding occipital neuralgia.

  14. 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.

  15. Effective DQE (eDQE) for monoscopic and stereoscopic chest radiography imaging systems with the incorporation of anatomical noise

    Energy Technology Data Exchange (ETDEWEB)

    Boyce, Sarah J. [Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 and Department of Biomedical Engineering, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27695 (United States); Choudhury, Kingshuk Roy [Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Samei, Ehsan [Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Carl E. Ravin Advanced Imaging Laboratories, Department of Biomedical Engineering, Duke University, Durham, North Carolina 27705 (United States); Carl E. Ravin Advanced Imaging Laboratories, Department of Physics, Duke University, Durham, North Carolina 27705 (United States)

    2013-09-15

    Purpose: Stereoscopic chest biplane correlation imaging (stereo/BCI) has been proposed as an alternative modality to single view chest x-ray (CXR). The metrics effective modulation transfer function (eMTF), effective normalized noise power spectrum (eNNPS), and effective detective quantum efficiency (eDQE) have been proposed as clinically relevant metrics for assessing clinical system performance taking into consideration the magnification and scatter effects. This study compared the metrics eMTF, eNNPS, eDQE, and detectability index for stereo/BCI and single view CXR under isodose conditions at two magnifications for two anthropomorphic phantoms of differing sizes.Methods: Measurements for the eMTF were taken for two phantom sizes with an opaque edge test device using established techniques. The eNNPS was measured at two isodose conditions for two phantoms using established techniques. The scatter was measured for two phantoms using an established beam stop method. All measurements were also taken at two different magnifications with two phantoms. A geometrical phantom was used for comparison with prior results for CXR although the results for an anatomy free phantom are not expected to vary for BCI.Results: Stereo/BCI resulted in improved metrics compared to single view CXR. Results indicated that magnification can potentially improve the detection performance primarily due to the air gap which reduced scatter by ∼20%. For both phantoms, at isodose, eDQE(0) for stereo/BCI was ∼100 times higher than that for CXR. Magnification at isodose improved eDQE(0) by ∼10 times for stereo/BCI. Increasing the dose did not improve eDQE. The detectability index for stereo/BCI was ∼100 times better than single view CXR for all conditions. The detectability index was also not improved with increased dose.Conclusions: The findings indicate that stereo/BCI with magnification may improve detectability of subtle lung nodules compared to single view CXR. Results were improved

  16. The Effect of Latitudinal Variation on Shrimp Reproductive Strategies.

    Directory of Open Access Journals (Sweden)

    Madelon van de Kerk

    Full Text Available Reproductive strategies comprise the timing and frequency of reproductive events and the number of offspring per reproductive event, depending on factors such as climate conditions. Therefore, species that exhibit plasticity in the allocation of reproductive effort can alter their behavior in response to climate change. Studying how the reproductive strategy of species varies along the latitudinal gradient can help us understand and predict how they will respond to climate change. We investigated the effects of the temporal allocation of reproductive effort on the population size of brown shrimp (Farfantepenaeus aztecus along a latitudinal gradient. Multiple shrimp species exhibit variation in their reproductive strategies, and given the economic importance of brown shrimp to the commercial fishing sector of the Unites States, changes in the timing of their reproduction could have significant economic and social consequences. We used a stage-based, density-dependent matrix population model tailored to the life history of brown shrimp. Shrimp growth rates and environmental carrying capacity were varied based on the seasonal climate conditions at different latitudes, and we estimated the population size at equilibrium. The length of the growing season increased with decreasing latitude and the reproductive strategy leading to the highest population size changed from one annual birth pulse with high reproductive output to continuous low-output reproduction. Hence, our model confirms the classical paradigm of continuous reproduction at low latitudes, with increased seasonality of the breeding period towards the poles. Our results also demonstrate the potential for variation in climate to affect the optimal reproductive strategy for achieving maximum population sizes. Certainly, understanding these dynamics may inform more comprehensive management strategies for commercially important species like brown shrimp.

  17. 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.)

  18. 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.

  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. Effect of TYLCV Infection on Leaf Anatomical Structure and Protective Enzyme System of Tomato%TYLCV侵染对番茄叶片解剖结构和保护酶系统的影响

    Institute of Scientific and Technical Information of China (English)

    张永平; 张辉; 朱龙英; 朱为民

    2009-01-01

    [Objective] The aim was to study the effect of tomato yellow leaf curl virus (TYLCV) infection on leaf anatomical structure and protective enzyme system of tomato. [Method] The anatomical structure of infected and healthy leaves of tomato were observed and compared by using paraffin section method. The activity changes of SOD, POD and CAT in the infected leaves of tomato were determined. [Result] The results revealed that there were some differences in anatomical structure between healthy and infected leaves. Some cells of infected leaves were damaged so that the leaves curled and became yellow, which affected the normal function of organs. Compared with control, enzyme activities in the tomato plants infected by TYLCV were enhanced at the early periods and higher than that in control, then started to decline at the middle and late periods but lower than that in control. [Conclusion] After infection by TYLCV, the leaf anatomical structure of tomato was changed greatly and the protective enzyme system was damaged severely, and affected the normal physiological metabolic functions of tissues and organs in tomato in further.

  1. 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.

    Science.gov (United States)

    Bahadori, Amir A; Van Baalen, Mary; Shavers, Mark R; Dodge, Charles; Semones, Edward J; Bolch, Wesley E

    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.

  2. Anatomical adaptations of aquatic mammals.

    Science.gov (United States)

    Reidenberg, Joy S

    2007-06-01

    This special issue of the Anatomical Record explores many of the anatomical adaptations exhibited by aquatic mammals that enable life in the water. Anatomical observations on a range of fossil and living marine and freshwater mammals are presented, including sirenians (manatees and dugongs), cetaceans (both baleen whales and toothed whales, including dolphins and porpoises), pinnipeds (seals, sea lions, and walruses), the sea otter, and the pygmy hippopotamus. A range of anatomical systems are covered in this issue, including the external form (integument, tail shape), nervous system (eye, ear, brain), musculoskeletal systems (cranium, mandible, hyoid, vertebral column, flipper/forelimb), digestive tract (teeth/tusks/baleen, tongue, stomach), and respiratory tract (larynx). Emphasis is placed on exploring anatomical function in the context of aquatic life. The following topics are addressed: evolution, sound production, sound reception, feeding, locomotion, buoyancy control, thermoregulation, cognition, and behavior. A variety of approaches and techniques are used to examine and characterize these adaptations, ranging from dissection, to histology, to electron microscopy, to two-dimensional (2D) and 3D computerized tomography, to experimental field tests of function. The articles in this issue are a blend of literature review and new, hypothesis-driven anatomical research, which highlight the special nature of anatomical form and function in aquatic mammals that enables their exquisite adaptation for life in such a challenging environment.

  3. The effect of deleterious mutations on neutral molecular variation

    Energy Technology Data Exchange (ETDEWEB)

    Charlesworth, B.; Morgan, M.T.; Charlesworth, D. (Univ. of Chicago, IL (United States))

    1993-08-01

    Selection against deleterious alleles maintained by mutation may cause a reduction in the amount of genetic variability at linked neutral sites. This is because a new neutral variant can remain in a large population for a long period of time only if it is maintained in gametes that are free of deleterious alleles, and hence are not destined for rapid elimination from the population by selection. Approximate formulas are derived for the reduction below classical neutral values resulting from such background selection against deleterious mutations, for the mean times of fixation and loss of new mutations, nucleotide site diversity, and number of segregating sites. These formulas apply to random-mating populations with no genetic recombination, and to populations reproducing exclusively asexually or by self-fertilization. For a given selection regime and mating system, the reduction is an exponential function of the total mutation rate to deleterious mutations for the section of the genome involved. Simulations show that the effect decreases rapidly with increasing recombination frequency or rate of outcrossing. The mean time to loss of new neutral mutations and the total number of segregating neutral sites are less sensitive to background selection than the other statistics, unless the population size is of the order of a hundred thousand or more. The stationary distribution of allele frequencies at the neutral sites is correspondingly skewed in favor of rare alleles, compared with the classical neutral result. Observed reductions in molecular variation in low recombination genomic regions of sufficiently large size, for instance in the centromere-proximal regions of Drosophila autosomes or in highly selfing plant populations, may be partly due to background selection against deleterious mutations. 58 refs., 3 figs., 6 tabs.

  4. 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

  5. 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

  6. Effects of drain bias on the statistical variation of double-gate tunnel field-effect transistors

    Science.gov (United States)

    Choi, Woo Young

    2017-04-01

    The effects of drain bias on the statistical variation of double-gate (DG) tunnel field-effect transistors (TFETs) are discussed in comparison with DG metal–oxide–semiconductor FETs (MOSFETs). Statistical variation corresponds to the variation of threshold voltage (V th), subthreshold swing (SS), and drain-induced barrier thinning (DIBT). The unique statistical variation characteristics of DG TFETs and DG MOSFETs with the variation of drain bias are analyzed by using full three-dimensional technology computer-aided design (TCAD) simulation in terms of the three dominant variation sources: line-edge roughness (LER), random dopant fluctuation (RDF) and workfunction variation (WFV). It is observed than DG TFETs suffer from less severe statistical variation as drain voltage increases unlike DG MOSFETs.

  7. Anatomical pathology is dead? Long live anatomical pathology.

    Science.gov (United States)

    Nicholls, John M; Francis, Glenn D

    2011-10-01

    The standard diagnostic instrument used for over 150 years by anatomical pathologists has been the optical microscope and glass slide. The advent of immunohistochemistry in the routine laboratory in the 1980s, followed by in situ hybridisation in the 1990s, has increased the armamentaria available to the diagnostic pathologist, and this technology has led to changed patient management in a limited number of neoplastic diseases. The first decade of the 21 century has seen an increasing number of publications using proteomic technologies that promise to change disease diagnosis and management, the traditional role of an anatomical pathologist. Despite the plethora of publications on proteomics and pathology, to date there are actually limited data where proteomic technologies do appear to be of greater diagnostic value than the standard histological slide. Though proteomic techniques will become more prevalent in the future, it will need the expertise of an anatomical pathologist to dissect out and validate this added information.

  8. Effects of intraspecific variation in white cabbage (Brassica oleracea var. capitata) on soil organisms

    NARCIS (Netherlands)

    Kabouw, P.; Van der Putten, W.H.; Van Dam, N.M.; Biere, A.

    2010-01-01

    Intraspecific variation in plants can affect soil organisms. However, little is known about whether the magnitude of the effect depends on the degree of interaction with the roots. We analyzed effects of plant intraspecific variation on root herbivores and other soil organisms that interact directly

  9. Effects of intraspecific variation in white cabbage (Brassica oleracea var. Capitata) on soil ogranisms

    NARCIS (Netherlands)

    Kabouw, P.; Putten, van der W.H.; Dam, van N.M.; Biere, A.

    2010-01-01

    Intraspecific variation in plants can affect soil organisms. However, little is known about whether the magnitude of the effect depends on the degree of interaction with the roots. We analyzed effects of plant intraspecific variation on root herbivores and other soil organisms that interact directly

  10. 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.

  11. 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

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. Dissimilarity-based classification of anatomical tree structures

    DEFF Research Database (Denmark)

    Sørensen, Lauge; Lo, Pechin Chien Pau; Dirksen, Asger

    2011-01-01

    A novel method for classification of abnormality in anatomical tree structures is presented. A tree is classified based on direct comparisons with other trees in a dissimilarity-based classification scheme. The pair-wise dissimilarity measure between two trees is based on a linear assignment...... between the branch feature vectors representing those trees. Hereby, localized information in the branches is collectively used in classification and variations in feature values across the tree are taken into account. An approximate anatomical correspondence between matched branches can be achieved...... by including anatomical features in the branch feature vectors. The proposed approach is applied to classify airway trees in computed tomography images of subjects with and without chronic obstructive pulmonary disease (COPD). Using the wall area percentage (WA%), a common measure of airway abnormality in COPD...

  17. The Fate of Anatomical Collections

    NARCIS (Netherlands)

    Knoeff, Rina; Zwijnenberg, Robert

    2015-01-01

    Almost every medical faculty possesses anatomical and/or pathological collections: human and animal preparations, wax- and other models, as well as drawings, photographs, documents and archives relating to them. In many institutions these collections are well-preserved, but in others they are poorly

  18. 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.

  19. 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.

  20. 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...

  1. 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.

  2. 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.

  3. Meteorological effects on variation of airborne algae in Mexico

    Science.gov (United States)

    Rosas, Irma; Roy-Ocotla, Guadalupe; Mosiño, Pedro

    1989-09-01

    Sixteen species of algae were collected from 73.8 m3 of air. Eleven were obtained in Minatitlán and eleven in México City. The data show that similar diversity occurred between the two localities, in spite of the difference in altitude. This suggests that cosmopolitan airborne microorganisms might have been released from different sources. Three major algal divisions (Chlorophyta, Cyanophyta and Chrysophyta) formed the airborne algal group. Also, a large concentration of 2220 algae m-3 was found near sea-level, while lower amounts were recorded at the high altitude of México City. The genera Scenedesmus, Chlorella and Chlorococcum dominated. Striking relationships were noted between the concentration of airborne green and blue-green algae, and meteorological conditions such as rain, vapour pressure, temperature and winds for different altitudes. In Minatitlán a linear relationship was established between concentration of algae and both vapour pressure (mbar) and temperature (° C), while in México City the wind (m s-1) was associated with variations in the algal count.

  4. 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.

  5. 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.

  6. Músculo pronador redondo: variações anatômicas e predisposição para a compressão do nervo mediano Pronator teres muscle: anatomical variations and predisposition for the compression of the median nerve

    Directory of Open Access Journals (Sweden)

    Vilma Clóris de Carvalho

    2002-05-01

    Full Text Available O nervo mediano pode ser comprimido em nível de músculo pronador redondo (MPR, resultando na síndrome do pronador redondo. Objetivou-se analisar a constituição do MPR e sua relação com o nervo mediano na dissecação de 100 membros superiores humanos, oriundos de laboratórios de anatomia. Em 72% dos casos, o nervo mediano passou entre as cabeças umeral e ulnar do MPR. Em 15% a cabeça ulnar esteve ausente, com o nervo mediano passando posteriormente a cabeça umeral ou através dela. Em 9% a cabeça ulnar se fez representar por um feixe fibroso. Em 2% o nervo mediano passou através da cabeça ulnar e em 2% através da cabeça umeral, mesmo na presença da cabeça ulnar. Os dados sugerem que as variações na relação músculo/nervo representam fatores potenciais para a compressão do nervo mediano, por tornarem mais restrita a passagem desse nervo no antebraço.The median nerve can be compressed at the level of pronator teres muscle (PTM, resulting in the pronator teres syndrome. This work aim was to analyze the PTM and its relationship with the median nerve. In order to do so, we have dissected 100 human upper limbs from anatomy laboratories. In 72% of the cases, the median nerve passed between the umeral and ulnar heads of PTM. In 15% of the cases, the ulnar head was absent, with the median nerve passing behind the umeral head or through it. In 9%, a fibrous bundle represented the ulnar head. In 2%, the median nerve passed through the ulnar head and in 2% through the umeral head, even in the presence of the ulnar head. The data suggest that the variations in the relationship muscle/nerve represent potential factors for the median nerve compression, for they make the passage for this nerve in the forearm even narrower.

  7. Variation in pollinator effectiveness in swamp milkweed, Asclepias incarnata (Apocynaceae).

    Science.gov (United States)

    Ivey, Christopher T; Martinez, Pocholo; Wyatt, Robert

    2003-02-01

    The contribution of a pollinator toward plant fitness (i.e., its "effectiveness") can determine its importance for the plant's evolutionary ecology. We compared pollinators in a population of Asclepias incarnata (Apocynaceae) for several components of pollinator effectiveness over two flowering seasons to evaluate their importance to plant reproduction. Insects of the order Hymenoptera predominate in A. incarnata pollination, but there appears to be no specialization for pollination within this order. Pollinators varied significantly in nearly every component of effectiveness that we measured, including pollen load, removal and deposition of pollen, pollination efficiency (deposition/removal), flower-handling time, and potential for geitonogamy (fractional pollen deposition). The visitation rate of pollinators also varied significantly between years and through time within years. Pollination success and percentage fruit-set of unmanipulated plants in the population also varied significantly between years, and pollination success varied among sample times within years. Most components of effectiveness were weakly correlated, suggesting that the contributions of visitor species toward pollination varied among effectiveness components. Mean flower-handling time, however, was strongly correlated with several components, including pollen removal and deposition, pollination efficiency, and fractional pollen deposition. These findings highlight the significance of pollination variability for plant reproduction and suggest that time-dependent foraging behaviors may play an important role in determining pollinator effectiveness.

  8. 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.

  9. 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.

  10. 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)

  11. Modifier effects between regulatory and protein-coding variation.

    Directory of Open Access Journals (Sweden)

    Antigone S Dimas

    2008-10-01

    Full Text Available Genome-wide associations have shown a lot of promise in dissecting the genetics of complex traits in humans with single variants, yet a large fraction of the genetic effects is still unaccounted for. Analyzing genetic interactions between variants (epistasis is one of the potential ways forward. We investigated the abundance and functional impact of a specific type of epistasis, namely the interaction between regulatory and protein-coding variants. Using genotype and gene expression data from the 210 unrelated individuals of the original four HapMap populations, we have explored the combined effects of regulatory and protein-coding single nucleotide polymorphisms (SNPs. We predict that about 18% (1,502 out of 8,233 nsSNPs of protein-coding variants are differentially expressed among individuals and demonstrate that regulatory variants can modify the functional effect of a coding variant in cis. Furthermore, we show that such interactions in cis can affect the expression of downstream targets of the gene containing the protein-coding SNP. In this way, a cis interaction between regulatory and protein-coding variants has a trans impact on gene expression. Given the abundance of both types of variants in human populations, we propose that joint consideration of regulatory and protein-coding variants may reveal additional genetic effects underlying complex traits and disease and may shed light on causes of differential penetrance of known disease variants.

  12. Modifier effects between regulatory and protein-coding variation.

    Science.gov (United States)

    Dimas, Antigone S; Stranger, Barbara E; Beazley, Claude; Finn, Robert D; Ingle, Catherine E; Forrest, Matthew S; Ritchie, Matthew E; Deloukas, Panos; Tavaré, Simon; Dermitzakis, Emmanouil T

    2008-10-01

    Genome-wide associations have shown a lot of promise in dissecting the genetics of complex traits in humans with single variants, yet a large fraction of the genetic effects is still unaccounted for. Analyzing genetic interactions between variants (epistasis) is one of the potential ways forward. We investigated the abundance and functional impact of a specific type of epistasis, namely the interaction between regulatory and protein-coding variants. Using genotype and gene expression data from the 210 unrelated individuals of the original four HapMap populations, we have explored the combined effects of regulatory and protein-coding single nucleotide polymorphisms (SNPs). We predict that about 18% (1,502 out of 8,233 nsSNPs) of protein-coding variants are differentially expressed among individuals and demonstrate that regulatory variants can modify the functional effect of a coding variant in cis. Furthermore, we show that such interactions in cis can affect the expression of downstream targets of the gene containing the protein-coding SNP. In this way, a cis interaction between regulatory and protein-coding variants has a trans impact on gene expression. Given the abundance of both types of variants in human populations, we propose that joint consideration of regulatory and protein-coding variants may reveal additional genetic effects underlying complex traits and disease and may shed light on causes of differential penetrance of known disease variants.

  13. 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

    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...

  14. 林下耕作对滩地杨树木材解剖性质的影响研究%Study on the Effects of Tillage on Wood Anatomical Properties of Marshland Poplar

    Institute of Scientific and Technical Information of China (English)

    李宝; 朱涛; 徐斌; 黄庆丰; 刘金良

    2012-01-01

    本文对长江滩地这一特定立地条件下经过人为耕作与未耕作模式下的杨树木材解剖性质及其变异的关系进行了比较研究。结果表明:林下耕作纤维长度变化范围在792.67-1114.33μm,属中等长度纤维,林下耕作杨树的纤维长度明显比未耕作的要长,两者纤维长度、宽度差异显著,长宽比差异极显著;林下耕作木材导管比量为29%,木纤维比量为54%,木射线比量为17%,变异系数分别为13.8%、7.4%、23.5%;低于对照木材,提高了材质均匀性;两者导管与木纤维组织比量轴向变化趋势一致,分别呈波动上升与下降的趋势,但木射线组织比量变异趋势存在较大的差别。林下耕作杨木导管比量自髓心向外呈上升趋势,木射线组织比量随着年龄的增加逐渐下降,并呈现一定的波动性:未经耕作的杨树木材组织比量径向变异规律性不明显。%Forestland tillage; marshlands; Wood anatomical properties; Fiber morphology; Variation. Abstract: In this paper the test materials were collected from Kewei Experimental Forest Farm in Huaining County of Anhui Province. A comparative study was made on the relationship between the poplar wood anatomical properties and their variations under Yangtze River marshland site conditions in tillage and no-tillage modes. The results showed that in the tillage mode, the poplar fiber length variation range is between 792.67um-1 114.33 μm and belonged to the medium-length fiber, significantly longer than that in the no-tillage mode. The differences of the wood fiber length and width between the poplar with and without tillage were significant, and their length-width ratio difference was extremely significant. The proportions of the vessel, wood fiber and wood-ray in poplar with tillage were 29%, 54%, and 17% respectively, and their coefficients of variation were 13.8%, 7.4% and 23.5% respectively which were lower

  15. 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.

  16. 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

  17. Functionally informed cortex based alignment: an integrated approach for whole-cortex macro-anatomical and ROI-based functional alignment.

    Science.gov (United States)

    Frost, Martin A; Goebel, Rainer

    2013-12-01

    Due to anatomical variability across subjects many brain mapping experiments have analysis focused on a few particular regions of interest so as to circumvent the problem of sub-optimal statistics resulting from the lack of anatomical correspondence across subjects. Since the topographic distribution of experimental effects across the cortex is also often of interest, two separate analyses are often conducted, one on the regions of interest alone, as well as a separate 'whole brain' analysis with sub-optimal spatial correspondence across brains. In this paper we present a new group alignment procedure which incorporates, from each subject, both macro-anatomical (curvature) information and functional information from standard localizer experiments. After specifying appropriate parameters to weight anatomical and functional alignment forces, we were able to create a group cortical reconstruction which was well aligned in terms of both anatomical and functional areas. We observed an increase in the overlap of functional areas as well as an improvement in group statistics following this integrated alignment procedure. We propose that, using this alignment scheme, two separate analyses may not be necessary as both analyses can be integrated into a single procedure. After an integrated structural and functional alignment one is able to carry out a whole brain analysis with improved statistical sensitivity due to the reduction in spatial variation in the location of functional regions of interest which fCBA accomplishes. Furthermore, regions in the vicinity of localised and aligned regions-of-interest will also benefit from the integrated alignment.

  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. 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.

  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. 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.

  2. 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.

  3. 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.

  4. 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.

  5. Anatomical aspects of sinus floor elevations.

    Science.gov (United States)

    van den Bergh, J P; ten Bruggenkate, C M; Disch, F J; Tuinzing, D B

    2000-06-01

    Inadequate bone height in the lateral part of the maxilla forms a contra-indication for implant surgery. This condition can be treated with an internal augmentation of the maxillary sinus floor. This sinus floor elevation, formerly called sinus lifting, consists of a surgical procedure in which a top hinge door in the lateral maxillary sinus wall is prepared and internally rotated to a horizontal position. The new elevated sinus floor, together with the inner maxillary mucosa, will create a space that can be filled with graft material. Sinus lift procedures depend greatly on fragile structures and anatomical variations. The variety of anatomical modalities in shape of the inner aspect of the maxillary sinus defines the surgical approach. Conditions such as sinus floor convolutions, sinus septum, transient mucosa swelling and narrow sinus may form a (usually relative) contra-indication for sinus floor elevation. Absolute contra-indications are maxillary sinus diseases (tumors) and destructive former sinus surgery (like the Caldwell-Luc operation). The lateral sinus wall is usually a thin bone plate, which is easily penetrated with rotating or sharp instruments. The fragile Schneiderian membrane plays an important role for the containment of the bonegraft. The surgical procedure of preparing the trap door and luxating it, together with the preparation of the sinus mucosa, may cause a mucosa tear. Usually, when these perforations are not too large, they will fold together when turning the trap door inward and upward, or they can be glued with a fibrin sealant, or they can be covered with a resorbable membrane. If the perforation is too large, a cortico-spongious block graft can be considered. However, in most cases the sinus floor elevation will be deleted. Perforations may also occur due to irregularities in the sinus floor or even due to immediate contact of sinus mucosa with oral mucosa. Obstruction of the antro-nasal foramen is, due to its high location, not a

  6. Moose body mass variation revisited: disentangling effects of environmental conditions and genetics.

    Science.gov (United States)

    Herfindal, Ivar; Haanes, Hallvard; Solberg, Erling J; Røed, Knut H; Høgda, Kjell Arild; Sæther, Bernt-Erik

    2014-02-01

    Large-scale geographical variation in phenotypic traits within species is often correlated to local environmental conditions and population density. Such phenotypic variation has recently been shown to also be influenced by genetic structuring of populations. In ungulates, large-scale geographical variation in phenotypic traits, such as body mass, has been related to environmental conditions and population density, but little is known about the genetic influences. Research on the genetic structure of moose suggests two distinct genetic lineages in Norway, structured along a north-south gradient. This corresponds with many environmental gradients, thus genetic structuring provides an additional factor affecting geographical phenotypic variation in Norwegian moose. We investigated if genetic structure explained geographical variation in body mass in Norwegian moose while accounting for environmental conditions, age and sex, and if it captured some of the variance in body mass that previously was attributed to environmental factors. Genetic structuring of moose was the most important variable in explaining the geographic variation in body mass within age and sex classes. Several environmental variables also had strong explanatory power, related to habitat diversity, environmental seasonality and winter harshness. The results suggest that environmental conditions, landscape characteristics, and genetic structure should be evaluated together when explaining large-scale patterns in phenotypic characters or life history traits. However, to better understand the role of genetic and environmental effects on phenotypic traits in moose, an extended individual-based study of variation in fitness-related characters is needed, preferably in an area of convergence between different genetic lineages.

  7. Utilization management in anatomic pathology.

    Science.gov (United States)

    Lewandrowski, Kent; Black-Schaffer, Steven

    2014-01-01

    There is relatively little published literature concerning utilization management in anatomic pathology. Nonetheless there are many utilization management opportunities that currently exist and are well recognized. Some of these impact only the cost structure within the pathology department itself whereas others reduce charges for third party payers. Utilization management may result in medical legal liabilities for breaching the standard of care. For this reason it will be important for pathology professional societies to develop national utilization guidelines to assist individual practices in implementing a medically sound approach to utilization management.

  8. Anatomical and chemical characteristics associated with lodging resistance in wheat

    Institute of Scientific and Technical Information of China (English)

    Eryan; Kong; Dongcheng; Liu; Xiaoli; Guo; Wenlong; Yang; Jiazhu; Sun; Xin; Li; Kehui; Zhan; Dangqun; Cui; Jinxing; Lin; Aimin; Zhang

    2013-01-01

    Anatomical and chemical characteristics of stems affect lodging in wheat(Triticum aestivum L.) cultivars. Traits associated with lodging resistance, such as plant height, stem strength, culm wall thickness, pith diameter, and stem diameter, were extensively investigated in earlier studies. However, the solid stem trait was rarely considered. In this study, we measured a range of anatomical and chemical characteristics on solid and hollow stemmed wheat cultivars. Significant correlations were detected between resistance to lodging and several anatomical features, including width of mechanical tissue, weight of low internodes, and width of stem walls. Morphological features that gave the best indication of improved lodging resistance were increased stem width, width of mechanical tissue layer, and stem density. Multiple linear regression analysis showed that 99% of the variation in lodging resistance could be explained by the width of the mechanical tissue layer, suggesting that solid stemmed wheat has several anatomical features for increasing resistance to lodging. In addition, microsatellite markers GWM247 and GWM340 were linked to a single solid stem QTL on chromosome 3BL in a population derived from the cross Xinongshixin(solid stem)/Line 3159(hollow stem). These markers should be valuable in breeding wheat for solid stem.

  9. Determination of the third critical field of superconductors using constrained effective wave function containing two variational parameters

    Energy Technology Data Exchange (ETDEWEB)

    Xu Longdao; Gao Yuliang

    1985-09-01

    Two variational parameters are included in the most probable constrained effective wave function with the accurate Hamiltonian remained. The third critical field which coincides with the result in paper (1) has been easily obtained through the variational principle.

  10. Variation in wood fibre traits among eight populations of Dipterocarpus indicus in Western Ghats, India.

    Science.gov (United States)

    Prasad, A G Devi; Al-Sagheer, Nageeb A

    2012-03-01

    Wood elements and anatomical ratio of Dipterocarpus indicus were studied to evaluate variation among populations and to recommend for end selection. The variation of wood element [fibre length (FL), fibre diameter (FD), lumen diameter (LD), cell wall thickness (CWT), double wall thickness (DWT), and lumen volume (LV)] and anatomical ratio [fibre lumen area (FLA), slenderness ratio (SR) and runkel ratio (RR)] were investigated in a girth class of 100 - 120 cm among eight populations of Dipterocarpus indicus in Western Ghats, India. The study revealed a significant variations in FL (0.2426), FD (4.7019), LD (3.1689), CWT (2.7104), DWT and (5.4298) among populations. The variations in anatomical ratios were significant among populations except in case of LV. The causes of variations among populations in their wood traits were attributed to the site factors. The interaction between genetic makeup of wood traits combined with effects of edaphic, local and regional climatic conditions reflect the amount of variation among populations. The highest coefficient of variation (CV %) for FL, FD, CWT and DWT was recorded in population of Gundya whereas low coefficient of variation were recorded in the population of Makuta (FL), Devimane (FD, CWT and DWT), and Sampaje (LD). The wood of Dipterocarpus indicus was found undesirable for pulp wood but can be utilized for plywood timbers.

  11. Effects of sample size and intraspecific variation in phylogenetic comparative studies: a meta-analytic review.

    Science.gov (United States)

    Garamszegi, László Z; Møller, Anders P

    2010-11-01

    Comparative analyses aim to explain interspecific variation in phenotype among taxa. In this context, phylogenetic approaches are generally applied to control for similarity due to common descent, because such phylogenetic relationships can produce spurious similarity in phenotypes (known as phylogenetic inertia or bias). On the other hand, these analyses largely ignore potential biases due to within-species variation. Phylogenetic comparative studies inherently assume that species-specific means from intraspecific samples of modest sample size are biologically meaningful. However, within-species variation is often significant, because measurement errors, within- and between-individual variation, seasonal fluctuations, and differences among populations can all reduce the repeatability of a trait. Although simulations revealed that low repeatability can increase the type I error in a phylogenetic study, researchers only exercise great care in accounting for similarity in phenotype due to common phylogenetic descent, while problems posed by intraspecific variation are usually neglected. A meta-analysis of 194 comparative analyses all adjusting for similarity due to common phylogenetic descent revealed that only a few studies reported intraspecific repeatabilities, and hardly any considered or partially dealt with errors arising from intraspecific variation. This is intriguing, because the meta-analytic data suggest that the effect of heterogeneous sampling can be as important as phylogenetic bias, and thus they should be equally controlled in comparative studies. We provide recommendations about how to handle such effects of heterogeneous sampling.

  12. 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...

  13. Anatomical basis for the interpretation of CT-scan imaging of the lumbar spine. Pitfalls

    Energy Technology Data Exchange (ETDEWEB)

    Laredo, J.D.; Bard, M.

    1988-01-01

    A good understanding of the normal anatomy of the lumbar spine is required for the interpretation of CT-scans obtained for ischiatic or crural neuralgia. An attempt has been made to rely on precise terminology to designate each anatomical region pertaining to the lumbar canal. Examples of tomodensitometric investigations of the normal intervertebral space are given, and criteria allowing for the identification of normal anatomical variations are also provided.

  14. 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

  15. 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.

  16. Anatomical assessment of congenital heart disease.

    Science.gov (United States)

    Wood, John C

    2006-01-01

    Cardiac MRI (CMR) is replacing diagnostic cardiac catheterization as the modality of choice for anatomic and functional characterization of congenital heart disease (CHD) when echocardiographic imaging is insufficient. In this manuscript, we discuss the principles of anatomic imaging of CHD, placing emphasis on the appropriate choice and modification of pulse sequences necessary to evaluate infants and small children. Clinical examples are provided to illustrate the relative strengths and shortcomings of different CMR imaging techniques. Although cardiovascular function and flow techniques are not described, their role in evaluating the severity of anatomic defects is emphasized. Anatomic characterization represents the first component of a carefully-planned, integrated CMR assessment of CHD.

  17. Network models in anatomical systems.

    Science.gov (United States)

    Esteve-Altava, Borja; Marugán-Lobón, Jesús; Botella, Héctor; Rasskin-Gutman, Diego

    2011-01-01

    Network theory has been extensively used to model the underlying structure of biological processes. From genetics to ecology, network thinking is changing our understanding of complex systems, specifically how their internal structure determines their overall behavior. Concepts such as hubs, scale-free or small-world networks, common in the complexity literature, are now used more and more in sociology, neurosciences, as well as other anthropological fields. Even though the use of network models is nowadays so widely applied, few attempts have been carried out to enrich our understanding in the classical morphological sciences such as in comparative anatomy or physical anthropology. The purpose of this article is to introduce the usage of network tools in morphology; specifically by building anatomical networks, dealing with the most common analyses and problems, and interpreting their outcome.

  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. 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...... equity effects of congestion charges are likely to be overestimated....

  20. Wall thickness variation effect on tank’s shape behaviour under critical harmonic settlement

    Directory of Open Access Journals (Sweden)

    Ahmed Shamel Fahmy

    2016-12-01

    Full Text Available The purpose of this study was to investigate the effect of wall thickness variation on tank’s wall buckling mode under the effect of critical harmonic settlement for open top tanks. The study was performed on four tanks which have the same geometric and material properties except wall thickness, for each case the tank was subjected to several settlement waves which has the same settlement amplitude, and the buckling mode and critical vertical settlement results were compared. For buckling mode, the results show that tanks with wall thickness at a close range have similar buckling mode behaviour and in case using too thick wall the buckling mode starts to change. And for the effect on critical vertical settlement, the results show that vertical settlement is sensitive to any variation in wall thickness beside that settlement value changes with the effected wave number and this variation could change the whole behaviour of the tanks. The study recommended that in case of performing analysis for a tank with neglecting the variation in wall thickness values, the value of chosen wall thickness should be the average of wall thickness values obtained from the designed equation.

  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. 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

  3. 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.

  4. EFFECTS OF BUDESONIDE AND BAMBUTEROL ON CIRCADIAN VARIATION OF AIRWAY RESPONSIVENESS AND NOCTURNAL SYMPTOMS OF ASTHMA

    NARCIS (Netherlands)

    WEMPE, JB; TAMMELING, EP; POSTMA, DS; AUFFARTH, B; TEENGS, JP; KOETER, GH

    1992-01-01

    Effects of the inhaled corticosteroid budesonide and the oral beta-agonist bambuterol on the nocturnal worsening of asthma were studied in patients with allergic asthma with a circadian peak expiratory flow variation greater-than-or-equal-to 15% (group 1, n = 8) and

  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. 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.

  7. Variational method of determining effective moduli of polycrystals with tetragonal symmetry

    Science.gov (United States)

    Meister, R.; Peselnick, L.

    1966-01-01

    Variational principles have been applied to aggregates of randomly oriented pure-phase polycrystals having tetragonal symmetry. The bounds of the effective elastic moduli obtained in this way show a substantial improvement over the bounds obtained by means of the Voigt and Reuss assumptions. The Hill average is found to be a good approximation in most cases when compared to the bounds found from the variational method. The new bounds reduce in their limits to the Voigt and Reuss values. ?? 1966 The American Institute of Physics.

  8. Variational method of determining effective moduli of polycrystals: (A) hexagonal symmetry, (B) trigonal symmetry

    Science.gov (United States)

    Peselnick, L.; Meister, R.

    1965-01-01

    Variational principles of anisotropic elasticity have been applied to aggregates of randomly oriented pure-phase polycrystals having hexagonal symmetry and trigonal symmetry. The bounds of the effective elastic moduli obtained in this way show a considerable improvement over the bounds obtained by means of the Voigt and Reuss assumptions. The Hill average is found to be in most cases a good approximation when compared to the bounds found from the variational method. The new bounds reduce in their limits to the Voigt and Reuss values. ?? 1965 The American Institute of Physics.

  9. 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.

  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. 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.

  12. 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.

  13. Stationary variational estimates for the effective response and field fluctuations in nonlinear composites

    Science.gov (United States)

    Ponte Castañeda, Pedro

    2016-11-01

    This paper presents a variational method for estimating the effective constitutive response of composite materials with nonlinear constitutive behavior. The method is based on a stationary variational principle for the macroscopic potential in terms of the corresponding potential of a linear comparison composite (LCC) whose properties are the trial fields in the variational principle. When used in combination with estimates for the LCC that are exact to second order in the heterogeneity contrast, the resulting estimates for the nonlinear composite are also guaranteed to be exact to second-order in the contrast. In addition, the new method allows full optimization with respect to the properties of the LCC, leading to estimates that are fully stationary and exhibit no duality gaps. As a result, the effective response and field statistics of the nonlinear composite can be estimated directly from the appropriately optimized linear comparison composite. By way of illustration, the method is applied to a porous, isotropic, power-law material, and the results are found to compare favorably with earlier bounds and estimates. However, the basic ideas of the method are expected to work for broad classes of composites materials, whose effective response can be given appropriate variational representations, including more general elasto-plastic and soft hyperelastic composites and polycrystals.

  14. 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.

  15. 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…

  16. 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…

  17. 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 fem...

  18. Theory and experiment for the effect of vascular microstructure on surface tissue heat transfer--Part I: Anatomical foundation and model conceptualization.

    Science.gov (United States)

    Weinbaum, S; Jiji, L M; Lemons, D E

    1984-11-01

    A new theoretical model supported by ultrastructural studies and high-spatial resolution temperature measurements is presented for surface tissue heat transfer in a two-part study. In this first paper, vascular casts of the rabbit thigh prepared by the tissue clearance method were serially sectioned parallel to the skin surface to determine the detailed variation of the vascular geometry as a function of tissue depth. Simple quantitative models of the basic vascular structures observed were then analyzed in terms of their characteristic thermal relaxation lengths and a new three-layer conceptual model proposed for surface tissue heat transfer. Fine wire temperature measurements with an 80-micron average diameter thermocouple junction and spatial increments of 20 micrometers between measurement sites have shown for the first time the detailed temperature fluctuations in the microvasculature and have confirmed the fundamental assumptions of the proposed three-layer model for the deep tissue, skeletal muscle and cutaneous layers.

  19. 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)

  20. Effect of Parametric Uncertainties, Variations, and Tolerances on Thermohydraulic Performance of Flat Plate Solar Air Heater

    Directory of Open Access Journals (Sweden)

    Rajendra Karwa

    2014-01-01

    Full Text Available The paper presents results of an analysis carried out using a mathematical model to find the effect of the uncertainties, variations, and tolerances in design and ambient parameters on the thermohydraulic performance of flat plate solar air heater. Analysis shows that, for the range of flow rates considered, a duct height of 10 mm is preferred from the thermohydraulic consideration. The thermal efficiency changes by about 2.6% on variation in the wind heat transfer coefficient, ±5 K variation in sky temperature affects the efficiency by about ±1.3%, and solar insolation variation from 500 to 1000 Wm−2 affects the efficiency by about −1.5 to 1.3% at the lowest flow rate of 0.01 kgs−1 m−2 of the absorber plate with black paint. In general, these effects reduce with increase in flow rate and are lower for collector with selective coating on the absorber plate surface. The tolerances in the duct height and absorber plate emissivity should be small while positive tolerance of 3° in the collector slope for winter operation and ±3° for year round operation, and a positive tolerance for the gap between the absorber plate and glass cover at nominal value of 40 mm are recommended.

  1. 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.

  2. 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.

  3. Extra-anatomic transplantations in autologous adult cell therapies aiding anatomical regeneration and physiological recovery – An insight and categorization

    Directory of Open Access Journals (Sweden)

    Editorial

    2015-12-01

    cells (source originate from the ectoderm while the epithelial lining of the urethra (target arises from the endoderm and the process of dysfunctional cell replacement occurs within the target. Gingival fibroblasts originate from the neural crest (source while dermal fibroblasts are derived from mesoderm (target and the process that follows is again replacement of dysfunctional cells. These, we propose, should be termed as “Trans-germ Extra-anatomic Cell Therapy” (TECT. In both IECT and TECT the transplantation is extra-anatomic and the presently known mechanism of the transplanted cells in helping with the regeneration are different, however, the transplanted cells aid directly or indirectly with the anatomical regeneration and/or physiological recovery of the target tissue and thereby the organ. While it is to be noted that he mechanisms of such repair by these adult autologous cells in different applications vary from direct replacement of cells to aiding in repair by paracrine effect or secretion of growth factors and that the extent of such repair or regeneration too has significant variations, the significance of this categorization in future clinical therapy are worth a thorough investigation and evaluation and how we can harness the potential of this extraordinary transdifferentiation process for clinical benefits. Extra-anatomic transplantations of in vitro expanded mature adult cells, without any genetic manipulation or in vitro trans-differentiation, have yielded dramatic anatomical regeneration of the host tissues as well as physiological recovery. The fine details describing the transformation process between guest cells and the host tissues are incomplete. The principles underpinning this phenomena must be established to fully exploit its potential as a clinical therapy with broad application. The composition of the cell mass used as a source for transplantation therapy, in terms of stem cells, precursor cells and mature adult cells, as well as

  4. Hips and hearts: the variation in incentive effects of insurance across hospital procedures.

    Science.gov (United States)

    Doiron, Denise; Fiebig, Denzil G; Suziedelyte, Agne

    2014-09-01

    The separate identification of effects due to incentives, selection and preference heterogeneity in insurance markets is the topic of much debate. In this paper, we investigate the presence and variation in moral hazard across health care procedures. The key motivating hypothesis is the expectation of larger causal effects in the case of more discretionary procedures. The empirical approach relies on an extremely rich and extensive dataset constructed by linking survey data to administrative data for hospital medical records. Using this approach we are able to provide credible evidence of large moral hazard effects but for elective surgeries only.

  5. The Effect of an Extreme and Prolonged Population Bottleneck on Patterns of Deleterious Variation

    DEFF Research Database (Denmark)

    Pedersen, Casper-Emil T; Lohmueller, Kirk E; Grarup, Niels;

    2016-01-01

    to a markedly more extreme distribution of allele frequencies than seen for any other human population, making the Inuit the perfect population for investigating the effect of a bottleneck on patterns of deleterious variation. When comparing proxies for genetic load that assume an additive effect of deleterious......The genetic consequences of population bottlenecks on patterns of deleterious genetic variation in human populations are of tremendous interest. Based on exome sequencing of 18 Greenlandic Inuit here we show that the Inuit have undergone a severe ~20,000 year long bottleneck. This has led...... alleles, the Inuit show, at most, a slight increase in load compared to European, East Asian, and African populations. Specifically, we observe

  6. Topographic anatomical study of the sciatic nerve relationship to the posterior portal in hip arthroscopy

    Directory of Open Access Journals (Sweden)

    Berliet Assad Gomes

    2014-12-01

    Full Text Available Objective: To evaluate the anatomic topographic relation between the sciatic nerve in relation to the piriform muscle and the posterior portal for the establishment of hip arthroscopy. Methods: We dissected 40 hips of 20 corpses of adult Brazilians, 17 male and three female, six black, six brown and eight white. We studied the anatomical relationship between the sciatic nerve and the piriform muscle with their variations and the distance between the lateral edge of the sciatic nerve and the posterior portal used in hip arthroscopy. We then classified the anatomical alterations found in the path of the sciatic nerve on the piriform muscle. Results: Seventeen corpses had bilateral relationship between the sciatic nerve and the piriform muscle, i.e., type A. We found the following anatomical variations: 12.5% of variant type B; and an average distance between the sciatic nerve and the portal for arthroscopy of 2.98cm. One body had type B anatomical variation on the left hip and type A on the right. Conclusion: the making of the posterior arthroscopic portal to the hip joint must be done with careful marking of the trochanter massive; should there be difficult to find it, a small surgical access is recommended. The access point to the portal should not exceed two centimeters towards the posterior superior aspect of the greater trochanter, and must be made with the limb in internal rotation of 15 degrees.

  7. Effects of Variation in Truck Factor on Pavement Performance in Pakistan

    OpenAIRE

    Rabia Chaudry; Afsheen Bashir Memon

    2013-01-01

    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...

  8. 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

  9. Effect of March 9, 2016 Total Solar Eclipse on geomagnetic field variation

    Science.gov (United States)

    Ruhimat, Mamat; Winarko, Anton; Nuraeni, Fitri; Bangkit, Harry; Aris, M. Andi; Suwardi; Sulimin

    2016-11-01

    During solar eclipse, solar radiation to the Earth is blocked by the Moon. Thus, the ionization process in the ionosphere is disrupted, as well as the variation of geomagnetic field. The disturbance of geomagnetic field is caused by electric current in the E layer of the ionosphere. At low latitude, the current which is dominant in quiet day is the Sq currents. The blocking of solar radiation cause decrement in electron density in the blocked region. The aim of the research is to find the effect of total solar eclipse to the geomagnetic field. The measurement of the geomagnetic field variation during total solar eclipse on March 9, 2016 was carried out at the Meteorological station of BMKG in Ternate (0° 49' 45.20 "N; 127° 22' 54.00" E). By eliminating the geomagnetic disturbance that occurred in a daily geomagnetic field variation, the pattern of quiet day which is usually in a shape of smooth curve became affected. During the total solar eclipse on March 9, 2016 from 00:30 until 02:00 UT, we found that the geomagnetic field variation of the quiet day decreased by -5 nT.

  10. 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.

  11. 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.

  12. 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.

  13. Little effect of HSP90 inhibition on the quantitative wing traits variation in Drosophila melanogaster.

    Science.gov (United States)

    Takahashi, Kazuo H

    2017-02-01

    Drosophila wings have been a model system to study the effect of HSP90 on quantitative trait variation. The effect of HSP90 inhibition on environmental buffering of wing morphology varies among studies while the genetic buffering effect of it was examined in only one study and was not detected. Variable results so far might show that the genetic background influences the environmental and genetic buffering effect of HSP90. In the previous studies, the number of the genetic backgrounds used is limited. To examine the effect of HSP90 inhibition with a larger number of genetic backgrounds than the previous studies, 20 wild-type strains of Drosophila melanogaster were used in this study. Here I investigated the effect of HSP90 inhibition on the environmental buffering of wing shape and size by assessing within-individual and among-individual variations, and as a result, I found little or very weak effects on environmental and genetic buffering. The current results suggest that the role of HSP90 as a global regulator of environmental and genetic buffering is limited at least in quantitative traits.

  14. 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.

  15. Handedness and cerebral anatomical asymmetries in young adult males.

    Science.gov (United States)

    Hervé, Pierre-Yves; Crivello, Fabrice; Perchey, Guy; Mazoyer, Bernard; Tzourio-Mazoyer, Nathalie

    2006-02-15

    Using voxel-based morphometry, we measured the cerebral anatomical asymmetries in a sample of 56 young right-handed males and then compared voxelwise asymmetry indices of these subjects to those of 56 young left-handed males. In the right-handed, the clusters of grey matter asymmetry corresponding to the leftward occipital petalia and planum temporale asymmetries were retrieved. Strong rightward temporo-parietal asymmetries were also observed, but the rightward grey matter asymmetry in the frontal lobe was less massive than previously described. Group comparisons of left- and right-handed subjects' asymmetry maps, performed at a statistical threshold not corrected for multiple comparisons, revealed significant effects of handedness on this pattern of anatomical asymmetry in frontal regions, notably in the lower central and precentral sulci, and also in the planum temporale, with right-handed subjects being more leftward asymmetric. Concerning white matter, although almost no focal differences between left- and right-handed subjects were detected, volumetric analyses at the hemispheric level revealed a leftward asymmetry, which happened to be significantly less marked in the left-handed. This latter result, together with the pattern of leftward white matter asymmetries, suggested that anatomical correlates of the left hemispheric specialization for language would exist in white matter. In the population we studied, differences in anatomical asymmetry between left- and right-handed subjects provided structural arguments for a greater functional ambilaterality in left-handed subjects.

  16. Anatomic considerations for abdominally placed permanent left ventricular assist devices.

    Science.gov (United States)

    Parnis, S M; McGee, M G; Igo, S R; Dasse, K; Frazier, O H

    1989-01-01

    To determine anatomic parameters for a permanent, electrically actuated left ventricular assist device (LVAD), the effects of abdominal placement of pneumatic LVADs used as temporary support for patients awaiting heart transplantation was studied. Understanding the anatomic constraints imposed by the abdominal viscera in LVAD placement is crucial, because improper placement can result in compression or obstruction of adjacent structures. Anatomic compatibility was assessed in four men (age 22-48 years) who were supported by the LVAD for over 1 month (range 35-132 days). The pump was intraperitoneally placed in the left upper quadrant. Radiographic techniques were employed, including CT scanning (with patients supine) and contrast imaging (patients in anatomical position), and the pump and conduits appeared to be properly positioned, with minimal compression of the body of the stomach, and no obstruction of adjacent organs. Three patients returned to a solid food diet and exercised daily by stationary cycling and walking. No signs of migration or erosion of the pump were present at the time of LVAD removal and cardiac transplantation. Successful clinical experience with short-term use of the LVAD suggests that the electrically actuated device can be well tolerated in patients requiring permanent left ventricular assistance.

  17. Effect of mass variation on the dynamics of receiver aircraft during aerial refueling

    Science.gov (United States)

    Mao, Weixin

    This dissertation presents the results of a study of the dynamic behavior of two aircraft that are flying in formation while one of them (the receiver) is being refueled by the other (the tanker) in mid-flight. The current procedure for aerial refueling requires that the receiver aircraft fly below, behind, and in relatively close proximity of the tanker for refueling to be possible. This means that the receiver aircraft is subjected to the full impact of the tanker wake turbulence; and this can clearly have a major impact on the motion of the receiver craft. Another important fact about aerial refueling is that large quantity of fuel is transferred from one vehicle to the other in a relatively short time. The resulting change in mass and the attendant change in aircraft inertia properties can also affect the dynamics of the aircraft system during fuel transfer. The principal goal of this project is to investigate the importance of this latter effect. This work accomplishes two main objectives. First, it shows how mass variation can be effectively factored into an analytical study of in-flight refueling; and it does this while keeping the analyses involved manageable. In addition, a numerical study of the equations of motion is utilized to extract useful information on how mass variation and some changes in receiver aircraft parameters can affect the motion of the receiver relative to the tanker. Results obtained indicate that mass variation due to fuel transfer compounds the difficulties created by tanker wake turbulence. In order to keep the receiver aircraft at a fixed position relative to the tanker during aerial refueling, appreciable adjustments must be made to the receiver's angle of attack, throttle setting and elevator deflection. A larger refueling rate demands even larger adjustments. Changes in certain other parameters related to aerial refueling can also amplify the effects of mass variation on the receiver motion, or influence the system's dynamics in

  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. Maternal effects and maternal selection arising from variation in allocation of free amino acid to eggs

    Science.gov (United States)

    Newcombe, Devi; Hunt, John; Mitchell, Christopher; Moore, Allen J

    2015-01-01

    Maternal provisioning can have profound effects on offspring phenotypes, or maternal effects, especially early in life. One ubiquitous form of provisioning is in the makeup of egg. However, only a few studies examine the role of specific egg constituents in maternal effects, especially as they relate to maternal selection (a standardized selection gradient reflecting the covariance between maternal traits and offspring fitness). Here, we report on the evolutionary consequences of differences in maternal acquisition and allocation of amino acids to eggs. We manipulated acquisition by varying maternal diet (milkweed or sunflower) in the large milkweed bug, Oncopeltus fasciatus. Variation in allocation was detected by examining two source populations with different evolutionary histories and life-history response to sunflower as food. We measured amino acids composition in eggs in this 2 × 2 design and found significant effects of source population and maternal diet on egg and nymph mass and of source population, maternal diet, and their interaction on amino acid composition of eggs. We measured significant linear and quadratic maternal selection on offspring mass associated with variation in amino acid allocation. Visualizing the performance surface along the major axes of nonlinear selection and plotting the mean amino acid profile of eggs from each treatment onto the surface revealed a saddle-shaped fitness surface. While maternal selection appears to have influenced how females allocate amino acids, this maternal effect did not evolve equally in the two populations. Furthermore, none of the population means coincided with peak performance. Thus, we found that the composition of free amino acids in eggs was due to variation in both acquisition and allocation, which had significant fitness effects and created selection. However, although there can be an evolutionary response to novel food resources, females may be constrained from reaching phenotypic optima with

  20. Considerations of variations in ionospheric field effects in mapping equatorial lithospheric Magsat magnetic anomalies

    Science.gov (United States)

    Ravat, D.; Hinze, W. J.

    1993-01-01

    The longitudinal, seasonal, and altitude-dependent variability of the magnetic field in equatorial latitudes is investigated to determine the effect of these variabilities on the isolation of lithospheric Magsat magnetic anomalies. It was found that the amplitudes of the dawn dip-latitude averages were small compared to the dusk averages, and that they were of the opposite sign. The longitudinal variation in the equatorial amplitudes of the dawn dip-latitude averages was not entirely consistent with the present knowledge of the electrojet field. Based on the results, a procedure is implemented for reducing the equatorial ionospheric effects from the Magsat data on the lithospheric component.

  1. COMPARATIVE ANALYSIS OF QUANTUM EFFECTS IN NANOSCALE MULTIGATE MOSFETS USING VARIATIONAL APPROACH

    Directory of Open Access Journals (Sweden)

    V. PALANICHAMY

    2015-02-01

    Full Text Available In this work, the performance of multiple-gate SOI MOSFETs is analysed using variational approach including quantum effects. An analytical model is derived to accounting the quantum effects at the silicon (Si/silicon dioxide (SiO2 interface. A general procedure is used for calculating the quantum inversion charge density. Using this inversion charge density, the drain current is obtained. Our model results are compared with the simulation results and its shows very good agreement. Our results highlighted that cylindrical surrounding gate MOSFET is a good candidate to obtain the high drain current compared with other two devices.

  2. An effective approach to evaluate GCM simulated diurnal variation of clouds

    Science.gov (United States)

    Chen, Guoxing; Wang, Wei-Chyung

    2016-10-01

    Cloud radiative effects strongly depend on diurnal variations of insolation and cloud radiative properties. In general circulation models (GCMs), even when the daily-mean cloud properties agree with observations, errors in cloud diurnal cycle can still significantly impact the shortwave radiation and induce model biases. However, this aspect is overlooked in GCM evaluation and intercomparison programs (e.g., Coupled Model Intercomparison Project Phase 5 (CMIP5)), which mainly consider the daily-mean cloud fraction. This study presents a simple approach of using a diagnostic parameter, the "effective-daytime cloud fraction" which accounts for the concurrent variation of clouds and insolation, to reveal GCM biases in cloud diurnal variations. The usefulness of the approach is illustrated by the significant biases of cloud diurnal cycle in the Modern-Era Retrospective analysis for Research and Applications (MERRA) reanalysis when compared with that in the International Satellite Cloud Climatology Project (ISCCP) data. It is thus suggested that the parameter be included as one of the GCM diagnostics for evaluating cloud diurnal cycle in model intercomparisons.

  3. 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.

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

    Directory of Open Access Journals (Sweden)

    Alexandra Krounis

    2015-12-01

    Full Text Available 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 existence 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.

  5. Formant-frequency variation and its effects on across-formant grouping in speech perception.

    Science.gov (United States)

    Roberts, Brian; Summers, Robert J; Bailey, Peter J

    2013-01-01

    How speech is separated perceptually from other speech remains poorly understood. In a series of experiments, perceptual organisation was probed by presenting three-formant (F1+F2+F3) analogues of target sentences dichotically, together with a competitor for F2 (F2C), or for F2+F3, which listeners must reject to optimise recognition. To control for energetic masking, the competitor was always presented in the opposite ear to the corresponding target formant(s). Sine-wave speech was used initially, and different versions of F2C were derived from F2 using separate manipulations of its amplitude and frequency contours. F2Cs with time-varying frequency contours were highly effective competitors, whatever their amplitude characteristics, whereas constant-frequency F2Cs were ineffective. Subsequent studies used synthetic-formant speech to explore the effects of manipulating the rate and depth of formant-frequency change in the competitor. Competitor efficacy was not tuned to the rate of formant-frequency variation in the target sentences; rather, the reduction in intelligibility increased with competitor rate relative to the rate for the target sentences. Therefore, differences in speech rate may not be a useful cue for separating the speech of concurrent talkers. Effects of competitors whose depth of formant-frequency variation was scaled by a range of factors were explored using competitors derived either by inverting the frequency contour of F2 about its geometric mean (plausibly speech-like pattern) or by using a regular and arbitrary frequency contour (triangle wave, not plausibly speech-like) matched to the average rate and depth of variation for the inverted F2C. Competitor efficacy depended on the overall depth of frequency variation, not depth relative to that for the other formants. Furthermore, the triangle-wave competitors were as effective as their more speech-like counterparts. Overall, the results suggest that formant-frequency variation is critical for

  6. 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.

  7. [Establishment of anatomical terminology in Japan].

    Science.gov (United States)

    Shimada, Kazuyuki

    2008-12-01

    The history of anatomical terminology in Japan began with the publication of Waran Naikei Ihan-teimŏ in 1805 and Chŏtei Kaitai Shinsho in 1826. Although the establishment of Japanese anatomical terminology became necessary during the Meiji era when many western anatomy books imported into Janan were translated, such terminology was not unified during this period and varied among translators. In 1871, Tsukumo Ono's Kaibŏgaku Gosen was published by the Ministry of Education. Although this book is considered to be the first anatomical glossary terms in Japan, its contents were incomplete. Overseas, the German Anatomical Society established a unified anatomical terminology in 1895 called the Basle Nomina Anatomica (B.N.A.). Based on this development, Kaibŏgaku Meishŭ which follows the BNA, by Buntarŏ Suzuki was published in 1905. With the subsequent establishment in 1935 of Jena Nomina Anatomica (J.N.A.), the unification of anatomical terminology was also accelerated in Japan, leading to the further development of terminology.

  8. Early Effects of Combretastatin A4 Phosphate Assessed by Anatomic and Carbogen-Based Functional Magnetic Resonance Imaging on Rat Bladder Tumors Implanted in Nude Mice

    Directory of Open Access Journals (Sweden)

    Carole D. Thomas

    2006-07-01

    Full Text Available Combretastatin A4 phosphate (CA4P causes rapid disruption of the tumor vasculature and is currently being evaluated for antivascular therapy. We describe the initial results obtained with a noninvasive multiparametric magnetic resonance imaging (MRI approach to assess the early effects of CA4P on rat bladder tumors implanted on nude mice. MRI (4.7 T comprised a fast spin-echo sequence for growth curve assessment; a multislice multiecho sequence for T2 measurement before, 15 minutes after, 24 hours after CA4P (100 mg/kg; and a fast T2W* gradient-echo sequence to assess MR signal modification under carbogen breathing before, 35 minutes after, 24 hours after CA4P. The tumor fraction with increased T2W* signal intensity under carbogen (T+ was used to quantify CA4P effect on functional vasculature. CA4P slowed tumor growth over 24 hours and accelerated necrosis development. T+ decrease was observed already at 35 minutes post-CA4P. Early T2 increase was observed in regions becoming necrotic at 24 hours post-CA4P, as confirmed by high T2 and histology. These regions exhibited, under carbogen, a switch from T2W* signal increase before CA4P to a decrease postCA4P. The combination of carbogen-based functional MRI and T2 measurement may be useful for the early follow-up of antivascular therapy without the administration of contrast agents.

  9. MULTIDETECTOR CT STUDY OF ANATOMICAL VARIANTS OF ETHMOID SINUS

    Institute of Scientific and Technical Information of China (English)

    李玉华; 薛建平; 朱铭

    2004-01-01

    Objective To evaluate the significance of multidetector CT 3D reconstruction technique in showing anatomy of ethmoid sinus, at the same time, anatomic variations of ethmoid sinus and its clinical significance were also discussed. Methods 250 cases of ethmoid sinuses were scanned transversally by multidetector scaner, coronal and sagittal views were reconstructed. Results Coronal and sagittal views were good enough to make diagnosis. 5 kinds of common ethmoid sinus variations were seen, including pneumatization of ethmoid bulla (56. 5% ) , Onodi air cell(26% ) , Hailer cell(6. 5% ) ,low ethmoid foveolas( 4. 3% )and over intromigratiny lamella papyracea (6. 5% ). Conclusion The coronal and other special views of ethmoid sinus are showed clearly by 3 D reconstruction which can provide detailed image informations for functional endoscopic sinus surgery.

  10. A Need for Logical and Consistent Anatomical Nomenclature for Cutaneous Nerves of the Limbs

    Science.gov (United States)

    Gest, Thomas R.; Burkel, William E.; Cortright, Gerald W.

    2009-01-01

    The system of anatomical nomenclature needs to be logical and consistent. However, variations in translation to English of the Latin and Greek terminology used in Nomina Anatomica and Terminologia Anatomica have led to some inconsistency in the nomenclature of cutaneous nerves in the limbs. An historical review of cutaneous nerve nomenclature…

  11. 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.

  12. 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.

  13. Modelling the Colour of Strawberry Spread During Storage, Including Effects of Technical Variations

    Directory of Open Access Journals (Sweden)

    Kadivec Mirta

    2016-12-01

    Full Text Available The colour of freshly processed strawberry spread changes relatively rapidly from a bright red to a dull red, which then makes its appearance generally less acceptable for consumers. The colours of strawberry spreads following several processing conditions were measured under different storage conditions. Additional sugar and colorant had only slight effects on the colour decay, while exclusion of oxygen and daylight did not affect this process. The only condition that clearly maintained the freshly processed appearance was storage at 4°C. Hexagonal bottles were filled with the strawberry spreads and their colour was repeatedly measured at the six sides of the bottles, using a Minolta chroma meter. Data were analysed using non-linear indexed regression analysis based on a logistic function for the three colour aspect of a*, b* and L*. This technology allowed the determination of the variation in these data in terms of improved reliability (R2adj, >90%. It also allowed better interpretation of the processes involved. All variations in the data could be attributed to technical variation.

  14. 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.

  15. Temporal variation in genetic diversity and effective population size of Mediterranean and subalpine Arabidopsis thaliana populations.

    Science.gov (United States)

    Gomaa, Nasr H; Montesinos-Navarro, Alicia; Alonso-Blanco, Carlos; Picó, F Xavier

    2011-09-01

    Currently, there exists a limited knowledge on the extent of temporal variation in population genetic parameters of natural populations. Here, we study the extent of temporal variation in population genetics by genotyping 151 genome-wide SNP markers polymorphic in 466 individuals collected from nine populations of the annual plant Arabidopsis thaliana during 4 years. Populations are located along an altitudinal climatic gradient from Mediterranean to subalpine environments in NE Spain, which has been shown to influence key demographic attributes and life cycle adaptations. Genetically, A. thaliana populations were more variable across space than over time. Common multilocus genotypes were detected several years in the same population, whereas low-frequency multilocus genotypes appeared only 1 year. High-elevation populations were genetically poorer and more variable over time than low-elevation populations, which might be caused by a higher overall demographic instability at higher altitudes. Estimated effective population sizes were low but also showed a significant decreasing trend with increasing altitude, suggesting a deeper impact of genetic drift at high-elevation populations. In comparison with single-year samplings, repeated genotyping over time captured substantially higher amount of genetic variation contained in A. thaliana populations. Furthermore, repeated genotyping of populations provided novel information on the genetic properties of A. thaliana populations and allowed hypothesizing on their underlying mechanisms. Therefore, including temporal genotyping programmes into traditional population genetic studies can significantly increase our understanding of the dynamics of natural populations.

  16. Effects of Different Variations of Mental and Physical Practice on Sport Skill Learning in Adolescents with Mental Retardation

    Science.gov (United States)

    Hemayattalab, Rasool; Movahedi, Ahmadreza

    2010-01-01

    The purpose of this study was to investigate the effect of five variations of imagery and physical practice on learning of Basketball free throws in adolescents with mental retardation (AWMR). Forty AWMR were randomly assigned to five groups and performed a variation of practice: physical practice, mental practice, physical practice followed by…

  17. Genetics in endocrinology: genetic variation in deiodinases: a systematic review of potential clinical effects in humans.

    Science.gov (United States)

    Verloop, Herman; Dekkers, Olaf M; Peeters, Robin P; Schoones, Jan W; Smit, Johannes W A

    2014-09-01

    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 clinical endpoints. Interest in clinical effects of genetic variation in deiodinases has clearly increased. We aimed to provide an overview for the role of deiodinase polymorphisms in human physiology and morbidity. In this systematic review, studies evaluating the relationship between deiodinase polymorphisms and clinical parameters in humans were eligible. No restrictions on publication date were imposed. The following databases were searched up to August 2013: Pubmed, EMBASE (OVID-version), Web of Science, COCHRANE Library, CINAHL (EbscoHOST-version), Academic Search Premier (EbscoHOST-version), and ScienceDirect. Deiodinase physiology at molecular and tissue level is described, and finally the role of these polymorphisms in pathophysiological conditions is reviewed. Deiodinase type 1 (D1) polymorphisms particularly show moderate-to-strong relationships with thyroid hormone parameters, IGF1 production, and risk for depression. D2 variants correlate with thyroid hormone levels, insulin resistance, bipolar mood disorder, psychological well-being, mental retardation, hypertension, and risk for osteoarthritis. D3 polymorphisms showed no relationship with inter-individual variation in serum thyroid hormone parameters. One D3 polymorphism was associated with risk for osteoarthritis. Genetic deiodinase profiles only explain a small proportion of inter-individual variations in serum thyroid hormone levels. Evidence suggests a role of genetic deiodinase variants in certain pathophysiological conditions. The value for determination of deiodinase polymorphism in clinical practice needs further investigation.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. Socioeconomic variation in recall and perceived effectiveness of campaign advertisements to promote smoking cessation.

    Science.gov (United States)

    Niederdeppe, Jeff; Farrelly, Matthew C; Nonnemaker, James; Davis, Kevin C; Wagner, Lauren

    2011-03-01

    There are large disparities in cigarette smoking rates by socioeconomic status (SES) in many countries. There is mixed evidence about the relative effectiveness of smoking cessation media campaigns in promoting quitting between lower and higher SES populations, and studies suggest that some types of ad content may have differential effects by SES. We analyzed data from five waves of the New York Media Tracking Survey Online (MTSO), a web survey involving over 7000 adult smokers conducted between 2007 and 2009, to assess SES variation in response to smoking cessation ads. Smokers with low levels of education and income less often recalled ads focused on how to quit, and perceived them as less effective, than ads using graphic imagery or personal testimonials to convey why to quit. Contrary to predictions offered by the Stages of Change Model, we found no evidence that variation in readiness to quit smoking explained patterns of response by education. Results offer guidance for theorists and campaign planners in developing campaigns that are likely to promote cessation among less educated populations.

  6. Reinforced concrete bridges: effects due to corrosion and concrete young modulus variation

    Directory of Open Access Journals (Sweden)

    P. T. C. Mendes

    Full Text Available Most of the Brazilian bridges of federal road network are made of reinforced concrete and are more than 30 years old, with little information about the mechanical properties of their constitutive materials. Along the service life of these bridges much modification occurred on vehicles load and geometry and in design standard. Many of them show signs of concrete and steel deterioration and their stability conditions are unknown. With the aim of contributing to the structural evaluation of reinforced concrete bridges it was decided to analyze the stresses in reinforced concrete bridge sections to verify the effects due to reinforcement corrosion and variation of the concrete Young modulus on the stress distribution regarding several load patterns and cracking effects in a representative bridge of the Brazilian road network with different longitudinal reinforcement taxes and two concrete Young modulus, Ec and 0.5Ec, and with different percentage of reinforcement corrosion. The analysis considered two finite element models: frame and shell elements as well as solid elements. The results indicate that these variation effects are more significant in reinforcement bars than in concrete.

  7. 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.

  8. 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.

  9. Anatomical study of sciatic nerve and common peroneal nerve compression

    Institute of Scientific and Technical Information of China (English)

    Mingzhao Jia; Qing Xia; Jinmin Sun; Qiang Zhou; Weidong Wang

    2008-01-01

    BACKGROUND: Many diseases of the common peroneal nerve are a result of sciatic nerve injury. The present study addresses whether anatomical positioning of the sciatic nerve is responsible for these injuries. OBJECTIVE: To analyze anatomical causes of sciatic nerve and common peroneal nerve injury by studying the relationship between the sciatic nerve and piriformis. DESIGN, TIME AND SETTING: Observe and measure repeatedly. The experiment was conducted in the Department of Anatomy, Tianjin Medical College between January and June 2005. MATERIALS: Fifty-two adult cadavers 33 males and 19 females, with a total of 104 hemispheres, and fixed with formaldehyde, were provided by Tianjin Medical College and Tianjin Medical University. METHODS: A posterior cut was made from the lumbosacral region to the upper leg, fully exposing the piriformis and path of the sciatic nerve. MAIN OUTCOME MEASURES: (1) Anatomical characteristics of the tibial nerve and common peroneal nerve. (2) According to different areas where the sciatic nerve crosses the piriformis, the study was divided into two types--normal and abnormal. Normal is considered to be when the sciatic nerve passes through the infrapiriform foramen. Remaining pathways are considered to be abnormal. (3) Observe the relationship between the suprapiriform foramen, infrapiriform foramen, as well as the superior and inferior space of piriformis. RESULTS: (1) The nerve tract inside the common peroneal nerve is smaller and thinner, with less connective tissue than the tibial nerve. When pathological changes or variations of the piriformis, or over-abduction of the hip joint, occur, injury to the common peroneal nerve often arises due to blockage and compression. (2) A total of 76 hemispheres (73.08%) were normal, 28 were abnormal (26.92%). The piriformis can be injured, and the sciatic nerve can become compressed, when the hip joint undergoes intorsion, extorsion, or abduction. (3) The structures between the infrapiriform and

  10. Induction effects of geomagnetic disturbances in the geo-electric field variations at low latitudes

    Science.gov (United States)

    Doumbia, Vafi; Boka, Kouadio; Kouassi, Nguessan; Didier Franck Grodji, Oswald; Amory-Mazaudier, Christine; Menvielle, Michel

    2017-01-01

    In this study we examined the influences of geomagnetic activity on the Earth surface electric field variations at low latitudes. During the International Equatorial Electrojet Year (IEEY) various experiments were performed along 5° W in West Africa from 1992 to 1995. Among other instruments, 10 stations equipped with magnetometers and telluric electric field lines operated along a meridian chain across the geomagnetic dip equator from November 1992 to December 1994. In the present work, the induced effects of space-weather-related geomagnetic disturbances in the equatorial electrojet (EEJ) influence area in West Africa were examined. For that purpose, variations in the north-south (Ex) and east-west (Ey) components of telluric electric field were analyzed, along with that of the three components (H, D and Z) of the geomagnetic field during the geomagnetic storm of 17 February 1993 and the solar flare observed on 4 April 1993. The most important induction effects during these events are associated with brisk impulses like storm sudden commencement (ssc) and solar flare effect (sfe) in the geomagnetic field variations. For the moderate geomagnetic storm that occurred on 17 February 1993, with a minimum Dst index of -110 nT, the geo-electric field responses to the impulse around 11:00 LT at LAM are Ex = 520 mV km-1 and Ey = 400 mV km-1. The geo-electric field responses to the sfe that occurred around 14:30 LT on 4 April 1993 are clearly observed at different stations as well. At LAM the crest-to-crest amplitude of the geo-electric field components associated with the sfe are Ex = 550 mV km-1 and Ey = 340 mV km-1. Note that the sfe impact on the geo-electric field variations decreases with the increasing distance of the stations from the subsolar point, which is located at about 5.13° N on 4 April. This trend does not reflect the sfe increasing amplitude near the dip equator due the high Cowling conductivity in the EEJ belt.

  11. 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.

  12. 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.

  13. 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.)

  14. Anatomical eponyms - unloved names in medical terminology.

    Science.gov (United States)

    Burdan, F; Dworzański, W; Cendrowska-Pinkosz, M; Burdan, M; Dworzańska, A

    2016-01-01

    Uniform international terminology is a fundamental issue of medicine. Names of various organs or structures have developed since early human history. The first proper anatomical books were written by Hippocrates, Aristotle and Galen. For this reason the modern terms originated from Latin or Greek. In a modern time the terminology was improved in particular by Vasalius, Fabricius and Harvey. Presently each known structure has internationally approved term that is explained in anatomical or histological terminology. However, some elements received eponyms, terms that incorporate the surname of the people that usually describe them for the first time or studied them (e.g., circle of Willis, follicle of Graff, fossa of Sylvious, foramen of Monro, Adamkiewicz artery). Literature and historical hero also influenced medical vocabulary (e.g. Achilles tendon and Atlas). According to various scientists, all the eponyms bring colour to medicine, embed medical traditions and culture to our history but lack accuracy, lead of confusion, and hamper scientific discussion. The current article presents a wide list of the anatomical eponyms with their proper anatomical term or description according to international anatomical terminology. However, since different eponyms are used in various countries, the list could be expanded.

  15. Spatial variation in nutrient and water color effects on lake chlorophyll at macroscales

    Science.gov (United States)

    Fergus, C. Emi; Finley, Andrew O.; Soranno, Patricia A.; Wagner, Tyler

    2016-01-01

    The nutrient-water color paradigm is a framework to characterize lake trophic status by relating lake primary productivity to both nutrients and water color, the colored component of dissolved organic carbon. Total phosphorus (TP), a limiting nutrient, and water color, a strong light attenuator, influence lake chlorophyll a concentrations (CHL). But, these relationships have been shown in previous studies to be highly variable, which may be related to differences in lake and catchment geomorphology, the forms of nutrients and carbon entering the system, and lake community composition. Because many of these factors vary across space it is likely that lake nutrient and water color relationships with CHL exhibit spatial autocorrelation, such that lakes near one another have similar relationships compared to lakes further away. Including this spatial dependency in models may improve CHL predictions and clarify how well the nutrient-water color paradigm applies to lakes distributed across diverse landscape settings. However, few studies have explicitly examined spatial heterogeneity in the effects of TP and water color together on lake CHL. In this study, we examined spatial variation in TP and water color relationships with CHL in over 800 north temperate lakes using spatially-varying coefficient models (SVC), a robust statistical method that applies a Bayesian framework to explore space-varying and scale-dependent relationships. We found that TP and water color relationships were spatially autocorrelated and that allowing for these relationships to vary by individual lakes over space improved the model fit and predictive performance as compared to models that did not vary over space. The magnitudes of TP effects on CHL differed across lakes such that a 1 μg/L increase in TP resulted in increased CHL ranging from 2–24 μg/L across lake locations. Water color was not related to CHL for the majority of lakes, but there were some locations where water color had a

  16. 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.

  17. Effects of hydraulic parameter cleaning variations on rate of penetration of soft formation insert bits

    Energy Technology Data Exchange (ETDEWEB)

    Doiron, H.H.; Deane, J.D.

    1982-09-01

    Effects of hydraulic cleaning parameter variations on rate of penetration response of 7 7/8 inch diameter soft formation insert bits have been measured in laboratory drilling tests. Tests were conducted in Mancos Shale rock samples at 700 psi and 4000 psi simulated overbalance pressure conditions using a 9.1 pound per gallon bentonite-barite water base drilling fluid. Bit hydraulic horsepower was varied from 0.72 to 9.5 HHP/in/sup 2/ using two or three nozzles in sizes ranging from 9/32 to 14/32 inches in diameter. Some improvements in ROP at constant bit hydraulic horsepower and impact force levels were obtained with two nozzle configurations vs. three nozzle configurations, but improvements were not consistently out of the range of normal test to test variations. Reduction in drilling costs due to the measured response of ROP to improved hydraulic cleaning is compared to increased operating costs required to provide additional hydraulics. Results indicate that bit hydraulic horsepower levels in excess of popular rules of thumb are cost effective in slow drilling due to high overbalance pressure.

  18. 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.

  19. 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...

  20. Effects of salinity variations on pore water flow in salt marshes

    Science.gov (United States)

    Shen, Chengji; Jin, Guangqiu; Xin, Pei; Kong, Jun; Li, Ling

    2015-06-01

    Spatial and temporal salinity variations in surface water and pore water commonly exist in salt marshes under the combined influence of tidal inundation, precipitation, evapotranspiration, and inland freshwater input. Laboratory experiments and numerical simulations were conducted to investigate how density gradients associated with salinity variations affect pore water flow in the salt marsh system. The results showed that upward salinity (density) gradients could lead to flow instability and the formation of salt fingers. These fingers, varying in size with the distance from the creek, modified significantly the pore water flow field, especially in the marsh interior. While the flow instability enhanced local salt transport and mixing considerably, the net effect was small, causing only a slight increase in the overall mass exchange across the marsh surface. In contrast, downward salinity gradients exerted less influence on the pore water flow in the marsh soil and slightly weakened the surface water and groundwater exchange across the marsh surface. Numerical simulations revealed similar density effects on pore water flow at the field scale under realistic conditions. These findings have important implications for studies of marsh soil conditions concerning plant growth as well as nutrient exchange between the marsh and coastal marine system.

  1. 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.

  2. Anatomical, functional and molecular biomarker applications of magnetic resonance neuroimaging.

    Science.gov (United States)

    Liu, Christina H

    2015-01-01

    MRI and magnetic resonance spectroscopy (MRS) along with computed tomography and PET are the most common imaging modalities used in the clinics to detect structural abnormalities and pathological conditions in the brain. MRI generates superb image resolution/contrast without radiation exposure that is associated with computed tomography and PET; MRS and spectroscopic imaging technologies allow us to measure changes in brain biochemistry. Increasingly, neurobiologists and MRI scientists are collaborating to solve neuroscience problems across sub-cellular through anatomical levels. To achieve successful cross-disciplinary collaborations, neurobiologists must have sufficient knowledge of magnetic resonance principles and applications in order to effectively communicate with their MRI colleagues. This review provides an overview of magnetic resonance techniques and how they can be used to gain insight into the active brain at the anatomical, functional and molecular levels with the goal of encouraging neurobiologists to include MRI/MRS as a research tool in their endeavors.

  3. 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.

  4. Anatomical study of the confluence of the sinuses with contrast-enhanced magnetic resonance venography

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Keiko; Matsui, Osamu; Ueda, Fumiaki [Kanazawa University School of Medicine, Department of Radiology, Kanazawa, Ishikawa (Japan); Suzuki, Masayuki [Kanazawa University School of Health Science, Department of Radiological Technology, Kanazawa, Ishikawa (Japan)

    2006-05-15

    It is important that each dural sinus can be recognized during brain surgery and that the venous route can be used for interventional procedures. In this study, the anatomical features and patterns of the confluence of the sinuses were analyzed. The technique of contrast-enhanced three-dimensional magnetic resonance venography was used in 549 patients. There were many anatomical variations in the confluence of the sinuses. Most cases had wide communication between the right and left transverse sinuses. Careful examination of the confluence of the sinuses is essential for the preoperative evaluation of posterior cranial fossa lesions and interventional procedures using the venous route. (orig.)

  5. 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.

  6. 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...

  7. Effects of rizatriptan on the contingent negative variation in healthy women.

    Science.gov (United States)

    Zank, R; Strehl, U; Larbig, W; Kotchoubey, B

    2008-09-01

    The effect of the antimigraine drug rizatriptan on the amplitude and habituation of the contingent negative variation (CNV) in healthy women was examined in a randomized, double-blind, placebo-controlled trial. The test persons were assigned either to a drug (n = 20) or a placebo group (n = 20). The CNV was recorded three times: before, directly after, and 24 h after drug or placebo intake. The CNV paradigm was presented in a standard, a cued and a choice version. Rizatriptan led to an increase of CNV amplitude that depended on the level of difficulty of the task. Whereas there was no drug effect in the standard version, an amplitude increase was obtained mainly in the choice task. The results are in line with the ceiling theory of migraine, which assumes a rise of CNV amplitude if the serotonin level is lowered.

  8. 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.

  9. 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.

  10. Covariant variational approach to Yang-Mills theory: Effective potential of the Polyakov loop

    Science.gov (United States)

    Quandt, M.; Reinhardt, H.

    2016-09-01

    We compute the effective action of the Polyakov loop in S U (2 ) and S U (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 S U (2 ) and first order for S U (3 ). The critical temperatures obtained are in reasonable agreement with high-precision lattice data.

  11. 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.

  12. 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...

  13. A RARE VARIATION OF GREAT SAPHENOUS VEIN

    Directory of Open Access Journals (Sweden)

    Nakhate Manisha

    2014-11-01

    Full Text Available The venous system is more complex and variable than arterial system due to its frequent anatomical variations. This paper discusses the anatomy of the great saphenous vein and its variation observed in a male cadaver of around 60 years old.

  14. 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.

  15. 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.

  16. 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.

  17. 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

  18. 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

  19. 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.

  20. 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

    2016-07-08

    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.

  1. 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.

  2. 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

  3. 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

  4. Challenges from variation across regions in cost effectiveness analysis in multi-regional clinical trials

    Directory of Open Access Journals (Sweden)

    Yunbo Chu

    2016-10-01

    Full Text Available Economic evaluation in the form of cost-effectiveness analysis has become a popular means to inform decisions in healthcare. With multi-regional clinical trials in a global development program becoming a new venue for drug efficacy testing in recent decades, questions in methods for cost-effectiveness analysis in the multi-regional clinical trials setting also emerge. This paper addresses some challenges from variation across regions in cost effectiveness analysis in multi-regional clinical trials. Several discussion points are raised for further attention and a multi-regional clinical trial example is presented to illustrate the implications in industrial application. A general message is delivered to call for a depth discussion by all stakeholders to reach an agreement on a good practice in cost-effectiveness analysis in the multi-regional clinical trials. Meanwhile, we recommend an additional consideration of cost-effectiveness analysis results based on the clinical evidence from a certain homogeneous population as sensitivity or scenario analysis upon data availability.

  5. 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.

  6. 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.

  7. 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....

  8. 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.

  9. 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

  10. Anatomical and functional characteristics of carotid sinus stimulation in humans

    Science.gov (United States)

    Querry, R. G.; Smith, S. A.; Stromstad, M.; Ide, K.; Secher, N. H.; Raven, P. B.

    2001-01-01

    Transmission characteristics of pneumatic pressure to the carotid sinus were evaluated in 19 subjects at rest and during exercise. Either a percutaneous fluid-filled (n = 12) or balloon-tipped catheter (n = 7) was placed at the carotid bifurcation to record internal transmission of external neck pressure/neck suction (NP/NS). Sustained, 5-s pulses, and rapid ramping pulse protocols (+40 to -80 Torr) were recorded. Transmission of pressure stimuli was less with the fluid-filled catheter compared with that of the balloon-tipped catheter (65% vs. 82% negative pressure, 83% vs. 89% positive pressure; P Anatomical location of the carotid sinus averaged 3.2 cm (left) and 3.6 cm (right) from the gonion of the mandible with a range of 0-7.5 cm. Transmission was not altered by exercise or Valsalva maneuver, but did vary depending on the position of the carotid sinus locus beneath the sealed chamber. These data indicate that transmission of external NP/NS was higher than previously recorded in humans, and anatomical variation of carotid sinus location and equipment design can affect transmission results.

  11. Genetic variation in catechol-O-methyltransferase modifies effects of clonidine treatment in chronic fatigue syndrome.

    Science.gov (United States)

    Hall, K T; Kossowsky, J; Oberlander, T F; Kaptchuk, T J; Saul, J P; Wyller, V B; Fagermoen, E; Sulheim, D; Gjerstad, J; Winger, A; Mukamal, K J

    2016-10-01

    Clonidine, an α2-adrenergic receptor agonist, decreases circulating norepinephrine and epinephrine, attenuating sympathetic activity. Although catechol-O-methyltransferase (COMT) metabolizes catecholamines, main effectors of sympathetic function, COMT genetic variation effects on clonidine treatment are unknown. Chronic fatigue syndrome (CFS) is hypothesized to result in part from dysregulated sympathetic function. A candidate gene analysis of COMT rs4680 effects on clinical outcomes in the Norwegian Study of Chronic Fatigue Syndrome in Adolescents: Pathophysiology and Intervention Trial (NorCAPITAL), a randomized double-blinded clonidine versus placebo trial, was conducted (N=104). Patients homozygous for rs4680 high-activity allele randomized to clonidine took 2500 fewer steps compared with placebo (Pinteraction=0.04). There were no differences between clonidine and placebo among patients with COMT low-activity alleles. Similar gene-drug interactions were observed for sleep (Pinteraction=0.003) and quality of life (Pinteraction=0.018). Detrimental effects of clonidine in the subset of CFS patients homozygous for COMT high-activity allele warrant investigation of potential clonidine-COMT interaction effects in other conditions.

  12. FERTILITY VARIATION AND EFFECTIVE POPULATION SIZE IN A TEAK CLONAL SEED ORCHARD

    Directory of Open Access Journals (Sweden)

    Sumardi Sumardi

    2011-06-01

    Full Text Available A 27 year old  clonal seed orchard of teak (Tectona grandis L.f in Padangan, East Java comprising 24 clones, was evaluated for fertility, offspring diversity, and genetic drift. Flower and fruit productions were used to assess clone fertility in the orchard. Fertility variation measured as ‘sibling coefficient’ was found to be 1,62, having high genetic diversity (0,97 and low coancestry (0,03. The clones varied in fertility in which,  25 % of the most fertile clones in the orchard contributed to 47,5 % of flower and fruit yields. Effective population size in the orchard was 15, indicating that 15 of the clones contributed effectively to seed yield. Separating on the amounts of seeds that can be collected, individual collection, and proportional mixing of seed per clone might be useful in restricting over representation of highly reproductive clones thereby increasing genetic diversity in the seed crop. Another way to improve seed yield in the orchard is by increasing the effective population size. Thinning or prunning on highly reproductive clones might be useful in increasing effective population size.

  13. 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.

  14. Configurational Variations and Finite-Beta Effects on Neoclassical Viscosities and Flows in Stellarators

    Science.gov (United States)

    Breyfogle, M.; Marine, T.; Ware, A. S.; Spong, D. A.

    2008-11-01

    The impact of magnetic geometry on neoclassical flows and viscosities for the Helically Symmetric Experiment (HSX) is investigated using the PENTA code [1,2]. Specifically, two topics are investigated: (1) finite-beta effects and (2) configurational variations. The PENTA code is used to calculate flows in HSX with the vacuum magnetic geometry and with finite-beta magnetic surfaces from the VMEC equilibrium code. This is done for the standard quasi-helically symmetric configuration of HSX, a symmetry-breaking mirror configuration and a hill configuration. The impact of these changes in the magnetic geometry on neoclassical viscosities and flows in HSX will be discussed.[0pt] [1] D. A. Spong, Phys. Plasmas 12, 056114 (2005). [0pt] [2] D. A. Spong, Fusion Sci. Technology 50, 343 (2006).

  15. 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 polymorphism at the selected loci at equilibrium, and to compare the results with those expected for a neutral locus. The results show that the expected number of alleles maintained, and numbers of nucleotide differences between alleles, are relatively insensitive to the migration rate, and differentiation...... remains low even under very restricted migration. However, nucleotide divergence between copies of functionally identical alleles increases sharply when migration decreases. These results are discussed in relation to published surveys of allelic diversity in MHC and plant self-incompatibility systems...

  16. 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.

  17. 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...

  18. Giving Ourselves: The Ethics of Anatomical Donation

    Science.gov (United States)

    Gunderman, Richard B.

    2008-01-01

    In some European countries, such as Italy, medical education is threatened by a dearth of anatomical specimens. Such a shortage could spread to other nations, including the United States. This article addresses two ethical questions in body donation. Why might people choose to donate their bodies to education and science? What sorts of ethical…

  19. 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...

  20. [Anatomic variants of Meckel's cave on MRI].

    Science.gov (United States)

    Benoudiba, F; Hadj-Rabia, M; Iffenecker, C; Fuerxer, F; Bekkali, F; Francke, J P; Doyon, D

    1998-10-01

    Magnetic resonance imaging (MRI) gives an accurate analysis of Meckel's cave variability. Images were acquired in 50 patients with several sections for anatomical comparison. Using several sections, MRI is a suitable method for better analysis of the trigeminal cistern. The most frequent findings are symmetrical trigeminal cisterns. Expansion of Meckel's cave or its disappearance has pathological significance.

  1. TIBIAL LANDMARKS IN ACL ANATOMIC REPAIR

    Directory of Open Access Journals (Sweden)

    M. V. Demesсhenko

    2016-01-01

    Full Text Available Purpose: to identify anatomical landmarks on tibial articular surface to serve as reference in preparing tibial canal with respect to the center of ACL footprint during single bundle arthroscopic repair.Materials and methods. Twelve frozen knee joint specimens and 68 unpaired macerated human tibia were studied using anatomical, morphometric, statistical methods as well as graphic simulation.Results. Center of the tibial ACL footprint was located 13,1±1,7 mm anteriorly from posterior border of intercondylar eminence, at 1/3 of the distance along the line connecting apexes of internal and external tubercles and 6,1±0,5 mm anteriorly along the perpendicular raised to this point.Conclusion. Internal and external tubercles, as well as posterior border of intercondylar eminence can be considered as anatomical references to determine the center of the tibial ACL footprint and to prepare bone canals for anatomic ligament repair.

  2. Anatomical Data for Analyzing Human Motion.

    Science.gov (United States)

    Plagenhoef, Stanley; And Others

    1983-01-01

    Anatomical data obtained from cadavers and from water displacement studies with living subjects were used to determine the weight, center of gravity, and radius of gyration for 16 body segments. A lead model was used to study movement patterns of the trunk section of the body. (Authors/PP)

  3. 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.

  4. Evolution of the Anatomical Theatre in Padova

    Science.gov (United States)

    Macchi, Veronica; Porzionato, Andrea; Stecco, Carla; Caro, Raffaele

    2014-01-01

    The anatomical theatre played a pivotal role in the evolution of medical education, allowing students to directly observe and participate in the process of dissection. Due to the increase of training programs in clinical anatomy, the Institute of Human Anatomy at the University of Padova has renovated its dissecting room. The main guidelines in…

  5. 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

  6. Use of isopycnic plots to understand the role of density in SFC - I. Effect of pressure variation on retention factors.

    Science.gov (United States)

    Tarafder, Abhijit; Hill, Jason F; Iraneta, Pamela C; Fountain, Kenneth J

    2015-08-07

    This paper aims to demonstrate the effect of pressure variations in modifying analyte retention behavior in SFC. There is a general understanding that in SFC increasing pressure decreases the retention factor (k'), and vice versa. What is not clearly discussed or explained in any recent literature is that these variations can be very different at different operating pressures, temperatures and modifier concentrations. It is important to have a clearer understanding on these variabilities during method development and results analysis. In this paper the nature of k' variation with pressure, at different temperatures and modifier concentrations, will be explained with the help of isopycnic plots of CO2 and CO2+methanol mixtures.

  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. Variational Effect and Anharmonic Torsion on Kinetic Modeling for Initiation Reaction of Dimethyl Ether Combustion.

    Science.gov (United States)

    Guan, Yulei; Gao, Jing; Song, Yiming; Li, Yang; Ma, Haixia; Song, Jirong

    2017-02-09

    The reaction of dimethyl ether (DME) with molecular oxygen has been considered to be the dominant initiation pathway for DME combustion compared to the C-O bond fission. This work presents a detailed mechanism and kinetics investigation for the O2 + DME reaction with theoretical approaches. Using the CCSD(T)/6-311+G(2df,2pd) potential energy surface with the M06-2X/MG3S gradient, Hessian, and geometries, rate constants are evaluated by multistructural canonical variational transition-state theory (MS-CVT) including contributions from hindered rotation and multidimensional tunneling over the temperature range 200-2800 K. The CCSD(T) and QCISD(T) with 6-311+G(2df,2pd) calculations predict a barrier of 190-194 kJ mol(-1) for the O2 + DME reaction based on the optimized structures at various levels. It is proposed that there exists a weakly interacting adducts on the product side with subsequent dissociation to the separate HO2 and CH3OCH2 radicals. Torsions in transition state are found to be significantly coupled to generate four conformations whose contributions do influence the rate constant predictions. Variational effects are observed to be significant at high temperatures, while tunneling effect quickly becomes insignificant with temperature. Finally, four-parameter Arrhenius expression 9.14 × 10(13)(T/300)(-3.15) exp[-184.52(T + 110.23)/(T(2) + 110.23(2))] cm(3) mol(-1) s(-1) describes the temperature dependence of MS-CVT rate constants with small-curvature tunneling correction.

  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. 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.

  11. 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.

  12. [Uterosacral ligament and hypogastric nerve anatomical relationship. Application to deep endometriotic nodules surgery].

    Science.gov (United States)

    Azaïs, H; Collinet, P; Delmas, V; Rubod, C

    2013-03-01

    Endometriosis is a concern for 10 to 15% of women of childbearing age. The uterosacral ligament is the most frequent localization of deep infiltrating endometriosis. Laparoscopic excision of endometriotic nodules may lead to functional consequences due to potential hypogastric nerve lesion. Our aim is to study the anatomical relationship between the hypogastric nerve and the uterosacral ligament in order to reduce the occurrence of such nerve lesions during pelvic surgeries. We based our study on an anatomical and surgical literature review and on the anatomical dissection of a 56-year-old fresh female subject. The hypogastric nerves cross the uterosacral ligament approximately 30mm from the torus. They go through the pararectal space, 20mm below the ureter and join the inferior hypogastric plexus at the level of the intersection between the ureter and the posterior wall of the uterine artery, at approximately 20mm from the torus. No anatomical variation has been described to date in the path of the nerve, but in its presentation which may be polymorphous. Laparoscopy and robot-assisted laparoscopic surgery facilitate the pelvic nerves visualization and are the best approach for uterosacral endometriotic nodule nerve-sparing excision. Precise knowledge by the surgeon of the anatomical relationship between the hypogastric nerve and the uterosacral ligament is essential in order to decrease the risk of complication and postoperative morbidity for patient surgically treated for deep infiltrating endometriosis involving uterosacral ligament.

  13. Craniofacial pain and anatomical abnormalities of the nasal cavities.

    Science.gov (United States)

    Mendonça, Jeferson Cedaro de; Bussoloti Filho, Ivo

    2005-01-01

    The causal relation between anatomical variations of the nose and headaches and facial pain is analyzed through literature review of the topic. The pathogenesis that can be involved in this relation proves to be wider than simple alteration of nasal septum and turbinates that can cause mechanical stimulus through contact between these structures, which covers infectious factors, neurogenic inflammation, correlation with migraines and the role of nasal obstruction. The clinical findings of a lot of authors including the test with topical anesthetic to prove this causal relation, the indication of surgical treatment, in addition to good results of this treatment, are reported. The mechanism of pain relief obtained through surgical correction of nasal septum and turbinate is discussed. These data make us conclude that there are multiple etiologic factors involved, which makes us question the fundamental role of the mechanical aspect.

  14. Nationwide variation in the effects of temperature on infectious gastroenteritis incidence in Japan

    Science.gov (United States)

    Onozuka, Daisuke; Hagihara, Akihito

    2015-08-01

    Although several studies have investigated the effects of temperature on the incidence of infectious gastrointestinal disease in a single city or region, few have investigated variations in this association using nationwide data. We obtained weekly data, gathered between 2000 and 2012, pertaining to infectious gastroenteritis cases and weather variability in all 47 Japanese prefectures. A two-stage analysis was used to assess the nonlinear and delayed relationship between temperature and morbidity. In the first stage, a Poisson regression allowing for overdispersion in a distributed lag nonlinear model was used to estimate the prefecture-specific effects of temperature on morbidity. In the second stage, a multivariate meta-analysis was applied to pool estimates at the national level. The pooled overall relative risk (RR) was highest in the 59.9th percentile of temperature (RR, 1.08; 95% CI: 1.01, 1.15). Meta-analysis results also indicated that the estimated pooled RR at lower temperatures (25th percentile) began immediately but did not persist, whereas an identical estimate at a higher temperature (75th percentile) was delayed but persisted for several weeks. Our results suggest that public health strategies aimed at controlling temperature-related infectious gastroenteritis may be more effective when tailored according to region-specific weather conditions.

  15. Plasma and magnetic field variations in the distant magnetotail associated with near-earth substorm effects

    Science.gov (United States)

    Baker, D. N.; Bame, S. J.; Mccomas, D. J.; Zwickl, R. D.; Slavin, J. A.; Smith, E. J.

    1987-01-01

    Examination of many individual event periods in the ISEE 3 deep-tail data set has suggested that magnetospheric substorms produce a characteristic pattern of effects in the distant magnetotail. During the growth, or tail-energy-storage phase of substorms, the magnetotail appears to grow diametrically in size, often by many earth radii. Subsequently, after the substorm expansive phase onset at earth, the distant tail undergoes a sequence of plasma, field, and energetic-particle variations as large-scale plasmoids move rapidly down the tail following their disconnection from the near-earth plasma sheet. ISEE 3 data are appropriate for the study of these effects since the spacecraft remained fixed within the nominal tail location for long periods. Using newly available auroral electrojet indices (AE and AL) and Geo particle data to time substorm onsets at earth, superposed epoch analyses of ISEE 3 and near-earth data prior to, and following, substorm expansive phase onsets have been performed. These analyses quantify and extend substantially the understanding of the deep-tail pattern of response to global substorm-induced dynamical effects.

  16. Solar Sail Topology Variations Due to On-Orbit Thermal Effects

    Science.gov (United States)

    Banik, Jeremy A.; Lively, Peter S.; Taleghani, Barmac K.; Jenkins, Chrostopher H.

    2006-01-01

    The objective of this research was to predict the influence of non-uniform temperature distribution on solar sail topology and the effect of such topology variations on sail performance (thrust, torque). Specifically considered were the thermal effects due to on orbit attitude control maneuvers. Such maneuvers are expected to advance the sail to a position off-normal to the sun by as much as 35 degrees; a solar sail initially deformed by typical pre-tension and solar pressure loads may suffer significant thermally induced strains due to the non-uniform heating caused by these maneuvers. This on-orbit scenario was investigated through development of an automated analytical shape model that iterates many times between sail shape and sail temperature distribution before converging on a final coupled thermal structural affected sail topology. This model utilizes a validated geometrically non-linear finite element model and a thermal radiation subroutine. It was discovered that temperature gradients were deterministic for the off-normal solar angle cases as were thermally induced strains. Performance effects were found to be moderately significant but not as large as initially suspected. A roll torque was detected, and the sail center of pressure shifted by a distance that may influence on-orbit sail control stability.

  17. Effect of breakfast skipping on diurnal variation of energy metabolism and blood glucose.

    Science.gov (United States)

    Kobayashi, Fumi; Ogata, Hitomi; Omi, Naomi; Nagasaka, Shoichiro; Yamaguchi, Sachiko; Hibi, Masanobu; Tokuyama, Kumpei

    2014-01-01

    Epidemiological studies suggest an association between breakfast skipping and body weight gain, insulin resistance or type 2 diabetes. Time when meal is consumed affects postprandial increase in energy expenditure and blood glucose, and breakfast skipping may reduce 24 h energy expenditure and elevate blood glucose level. The present study evaluated the effect of breakfast skipping on diurnal variation of energy metabolism and blood glucose. The skipped breakfast was compensated by following big meals at lunch and supper. In a randomized repeated-measure design with or without breakfast, eight males stayed twice in a room-size respiratory chamber. Blood glucose was recorded with a continuous glucose monitoring system. Breakfast skipping did not affect 24 h energy expenditure, fat oxidation and thermic effect of food, but increased overall 24 h average of blood glucose (83 ± 3 vs 89 ± 2 mg/dl, P breakfast skipping. These observations suggest that changes in glucose homeostasis precede that of energy balance, in the potential sequence caused by breakfast skipping, if this dietary habit has any effect on energy balance.:

  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. 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.

  20. Assemblage organization in stream fishes: effects of environmental variation and interspecific interactions

    Science.gov (United States)

    Grossman, G.D.; Ratajczak, R.E.; Crawford, M. M.; Freeman, Mary C.

    1998-01-01

    We assessed the relative importance of environmental variation, interspecific competition for space, and predator abundance on assemblage structure and microhabitat use in a stream fish assemblage inhabiting Coweeta Creek, North Carolina, USA. Our study encompassed a ten year time span (1983-1992) and included some of the highest and lowest flows in the last 58 years. We collected 16 seasonal samples which included data on: 1) habitat availability (total and microhabitat) and microhabitat diversity, 2) assemblage structure (i.e., the number and abundances of species comprising a subset of the community), and 3) microhabitat use and overlap. We classified habitat availability data on the basis of year, season, and hydrologic period. Hydrologic period (i.e., pre-drought [PR], drought [D], and post-drought [PO]) represented the temporal location of a sample with respect to a four-year drought that occurred during the study. Hydrologic period explained a greater amount of variance in habitat availability data than either season or year. Total habitat availability was significantly greater during PO than in PR or D, although microhabitat diversity did not differ among either seasons or hydrologic periods. There were significantly fewer high-flow events (i.e., > 2.1 m3/s) during D than in either PR or PO periods. We observed a total of 16 species during our investigation, and the total number of species was significantly higher in D than in PR samples. Correlation analyses between the number of species present (total and abundant species) and environmental data yielded limited results, although the total number of species was inversely correlated with total habitat availability. A cluster analysis grouped assemblage structure samples by hydrologic period rather than season or year, supporting the contention that variation in annual flow had a strong impact on this assemblage. The drought had little effect on the numerical abundance of benthic species in this assemblage

  1. Finite element study on the anatomic transtibial technique for single-bundle anterior cruciate ligament reconstruction.

    Science.gov (United States)

    Bae, Ji Yong; Kim, Geon-Hee; Seon, Jong Keun; Jeon, Insu

    2016-05-01

    The anatomic transtibial (TT) technique is proposed as a new approach for single-bundle anterior cruciate ligament (ACL) reconstruction. Geometric models of the anatomic TT and anteromedial (AM) portal techniques were fabricated with a reconstructed knee joint model and virtual surgical operations. Grafts of 7 mm diameter were modeled and inserted into tunnels drilled in each model. In the models, the shape of the graft between the femur and the tibia, the lengths of the bone tunnels, and the femoral graft bending angles were evaluated. To evaluate the biomechanical effects of both techniques on the grafts, the contact pressures and maximum principal stresses in the grafts were calculated using the finite element method. The anatomic TT technique placed the femoral tunnel to the anatomic position of the native ACL femoral attachment site. In addition, it decreased the peak contact pressure and the maximum principal stress at the full extension position of the graft compared with the AM portal technique. The anatomic TT technique may be regarded as a superior surgical technique compared with the conventional TT and AM portal techniques. Because of the easy surgical operation involved, the technique decreases the operation time for ACL reconstruction and it provides a deformation behavior of grafts similar to that in the native ACL in a knee joint. With its few side effects, the anatomic TT technique may considerably help patients.

  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. 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.

  4. Genetic variation in the serotonin transporter gene influences ERP old/new effects during recognition memory.

    Science.gov (United States)

    Ross, Robert S; Medrano, Paolo; Boyle, Kaitlin; Smolen, Andrew; Curran, Tim; Nyhus, Erika

    2015-11-01

    Recognition memory is defined as the ability to recognize a previously encountered stimulus and has been associated with spatially and temporally distinct event-related potentials (ERPs). Allelic variations of the serotonin transporter gene (SLC6A4) have recently been shown to impact memory performance. Common variants of the serotonin transporter-linked polymorphic region (5HTTLPR) of the SLC6A4 gene result in long (l) and short (s) allelic variants with carriers of the s allele having lowered transcriptional efficiency. Thus, the current study examines the effects polymorphisms of the SLC6A4 gene have on performance and ERP amplitudes commonly associated with recognition memory. Electroencephalogram (EEG), genetic, and behavioral data were collected from sixty participants as they performed an item and source memory recognition task. In both tasks, participants studied and encoded 200 words, which were then mixed with 200 new words during retrieval. Participants were monitored with EEG during the retrieval portion of each memory task. EEG electrodes were grouped into four ROIs, left anterior superior, right anterior superior, left posterior superior, and right posterior superior. ERP mean amplitudes during hits in the item and source memory task were compared to correctly recognizing new items (correct rejections). Results show that s-carriers have decreased mean hit amplitudes in both the right anterior superior ROI 1000-1500ms post stimulus during the source memory task and the left anterior superior ROI 300-500ms post stimulus during the item memory task. These results suggest that individual differences due to genetic variation of the serotonin transporter gene influences recognition memory.

  5. 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.

  6. 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...... the variation is productivity and a negative relationship indicates density-dependence. We found that variation in walleye growth among water bodies is largely explained by food productivity - not density-dependence. These results suggest that we can’t detect density-dependence among lakes when density......Most fishes exhibit strong spatial variation in growth. Because fish growth and production are tightly linked, quantifying and explaining variation in growth can mean the difference between successful management and unforeseen collapse. However, disentangling the factors that are responsible...

  7. On the Road to Improved Scheduling: Reducing the Effects of Variation in Duration

    DEFF Research Database (Denmark)

    Lindhard, Søren; Wandahl, Søren

    2013-01-01

    Scheduling in onsite construction is based on commitments. Unmet commitments result in non-completions which leads to waste. Moreover, it is important that commitments are realistic to avoid both positive and negative variation in duration. Negative variation is destructive to plans and schedules...... and results in delays, while positive variation is destructive to productivity by creating unexploited gaps between activities, thus inducing unexploited capacity. By registering non-completion at three construction sites, the magnitude of activities inducing negative variation has been mapped. In total, 5424...... activities have been registered whereof 1450 activities ended up as non-completions. Thus, 27% of the scheduled activities did not finish on schedule. Both positive and negative variation can be minimized by improving the quality of the commitments. Moreover, positive variation can be exploited by: (a...

  8. A Probabilistic Approach to Examine the Effect of Chemistry Variations on Distortion During Industrial Gas Carburizing

    Science.gov (United States)

    Sahay, Satyam S.; Deshmukh, Vinayak; El-Zein, Mohamad

    2013-07-01

    Industrial carburizing operations have been traditionally simulated for several decades by solving the diffusion equation. However, using this deterministic approach, it is difficult to capture batch-to-batch variations in the properties attributed to process and chemistry variations. In the current study, a probabilistic approach is used to capture the variations in process parameters and alloy chemistry. The advantage of this approach is illustrated through a case study on reduction in distortion variations as well as its absolute value during the carburizing operation. Finally, some of the opportunities and challenges in the carburizing simulation are discussed.

  9. Modifying the Functional Movement Screen Deep Squat Test: The Effect of Foot and Arm Positional Variations.

    Science.gov (United States)

    McMillian, Danny J; Rynders, Zach G; Trudeau, Tyler R

    2016-04-01

    The functional movement screen (FMS) was developed as an evaluation tool for assessing the fundamental movement patterns believed to be prerequisites for functional activity. However, some of the FMS component movements, such as the deep overhead squat test (DST), likely represent novel motor challenges on which poor performance might reflect inexperience with the task rather than a movement impairment. The purpose of this study was to examine the effects of positional variations on DST scores in a population of young, healthy adults. We hypothesized that self-selecting foot positioning, removal of an overhead component, or changing both aspects of the DST would result in improvement in FMS scores. Twenty healthy subjects completed 4 squatting conditions in a counterbalanced sequence to eliminate carry over effects: DST, modified squat with hands at chest level and feet in the DST position (DSTO), modified squat with arms in the DST position and self-selected foot placement (DSTF), and modified squat with hands at chest level and self-selected foot placement (DSTB). A Friedman's analysis of variance and Wilcoxon signed-ranks' post hoc analysis revealed a significant difference between all squat conditions (p = 0.036), between DSTB-DST groups (p DST groups (p = 0.004), and DSTO-DSTB groups (p = 0.046). Each modified squat condition had an average score higher than the DST. These findings suggest that the FMS DST might underestimate an individual's ability to squat during functional tasks that involve self-selected foot and arm placement.

  10. 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.

  11. Effect of day-to-day variations in adrenal cortex hormone levels on abdominal symptoms

    Directory of Open Access Journals (Sweden)

    Tsumura Hideki

    2010-03-01

    Full Text Available Abstract Introduction The hypothalamic-pituitary-adrenal axis is known to be related to abdominal symptoms, and the relationship between abdominal pain and cortisol secretory patterns has been previously investigated using a cross-sectional approach. Here, we investigated the effect of day-to-day variations in salivary cortisol and dehydroepiandrosterone-sulfate levels on abdominal symptoms in healthy individuals. Methods Eleven college students (4 males and 7 females participated in this study. The participants were asked to collect their saliva immediately after awakening and before bedtime for eight consecutive days. They also completed a questionnaire about abdominal symptoms before bedtime. The linear mixed model was applied to analyze the effects of the day-by-day variability or the 8-day average adrenal hormone level (at awakening, before bedtime, slope from awakening to bedtime on abdominal symptoms. Results The day-to-day variability of cortisol levels before bedtime was negatively related with loose stool, while the day-to-day variability of the cortisol slope was positively correlated with loose stool. A low 8-day average dehydroepiandrosterone-sulfate level at awakening was positively related with frequent bowel movements, loose stool, and long bouts of severe abdominal pain. Likewise, a low 8-day average dehydroepiandrosterone-sulfate slope was positively related with long bouts of abdominal pain. Conclusions Low cortisol levels before bedtime and a steeper diurnal cortisol slope during the day may be related to bouts of diarrhea during the day.

  12. 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.

  13. 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

  14. A technical perspective in modern tree-ring research--how to overcome dendroecological and wood anatomical challenges.

    Science.gov (United States)

    Gärtner, Holger; Cherubini, Paolo; Fonti, Patrick; von Arx, Georg; Schneider, Loïc; Nievergelt, Daniel; Verstege, Anne; Bast, Alexander; Schweingruber, Fritz H; Büntgen, Ulf

    2015-03-05

    Dendroecological research uses information stored in tree rings to understand how single trees and even entire forest ecosystems responded to environmental changes and to finally reconstruct such changes. This is done by analyzing growth variations back in time and correlating various plant-specific parameters to (for example) temperature records. Integrating wood anatomical parameters in these analyses would strengthen reconstructions, even down to intra-annual resolution. We therefore present a protocol on how to sample, prepare, and analyze wooden specimen for common macroscopic analyses, but also for subsequent microscopic analyses. Furthermore we introduce a potential solution for analyzing digital images generated from common small and large specimens to support time-series analyses. The protocol presents the basic steps as they currently can be used. Beyond this, there is an ongoing need for the improvement of existing techniques, and development of new techniques, to record and quantify past and ongoing environmental processes. Traditional wood anatomical research needs to be expanded to include ecological information to this field of research. This would support dendro-scientists who intend to analyze new parameters and develop new methodologies to understand the short and long term effects of specific environmental factors on the anatomy of woody plants.

  15. 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.

  16. The Effect of Intertalker Variations on Acoustic-Perceptual Mapping in Cantonese and Mandarin Tone Systems

    Science.gov (United States)

    Peng, Gang; Zhang, Caicai; Zheng, Hong-Ying; Minett, James W.; Wang, William S.-Y.

    2012-01-01

    Purpose: This study investigates the impact of intertalker variations on the process of mapping acoustic variations on tone categories in two different tone languages. Method: Pitch stimuli manipulated from four voice ranges were presented in isolation through a blocked-talker design. Listeners were instructed to identify the stimuli that they…

  17. Temporal and spatial variations in wildlife population fluctuations in Greenland; The effect of climate, environment and man

    DEFF Research Database (Denmark)

    Moshøj, Charlotte Margaret; Forchhammer, Mads C.; Forbes, Valery E.

    2009-01-01

    Temporal and spatial variations in wildlife population fluctuations in Greenland; The effect of climate, environment and man Moshøj, C.M, M.C.Forchhammer and V.E. Forbes Temporal and spatial variations in wildlife population fluctuations in Greenland; The effect of climate, environment and man...... and mammals display distinct population fluctuations of varying temporal and spatial scale. In Greenland, historical records, archaeological findings and oral accounts passed on from Inuit elders all document that the presence of wildlife species and their population sizes have undergone pronounced....... The results of this study will model future predictions of wildlife populations under changing climate variables and human hunting pressure....

  18. 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.

  19. 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

  20. 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.

  1. Anatomical MRI with an atomic magnetometer.

    Science.gov (United States)

    Savukov, I; Karaulanov, T

    2013-06-01

    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 a 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 a 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 1.1 mm×1.4 mm in about 6 min of acquisition with SNR of 10. Some applications of the method are discussed. We discuss several measures to increase the sensitivity to reach a resolution 1 mm×1 mm.

  2. 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...

  3. 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

  4. 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.

  5. Effects of shading on seedling growth and leaf anatomical characteristics of Aquilaria sinensis%遮阴处理对土沉香幼苗生长和叶片解剖特征的影响

    Institute of Scientific and Technical Information of China (English)

    原慧芳; 魏丽萍; 田耀华; 岳海

    2013-01-01

    In order to understand the light requirement and adaptabihty of Aquilaria sinensis (Lour.) Spreng,seedlings morphology and leaf anatomical characteristics of Aquilaria sinensis seedlings under different light treatments (100%,50%,25% and 5% natural light) were studied.The results showed that different shade treatments had different effects on the leaf anatomical structure and seedling growth parameters of three Aquilaria sinensis provenances (Dabai,Dahuang and Yunnan).For all the three provenances,with the weakening of light intensity,the main veins,leaf thickness,palisade tissue thickness and leaf epidermal cells were generally decreased significantly (P < 0.05),the thickness of spongy tissue increased,and the lower leaf epidermis cell thickness showed varying change degrees.With the decrease of light intensity,leaf area ratio and leaf area increased in all the three provenances.For Yunnan provenance,the total biomass and absolute growth rate decreased as light intensity decreased,but for Dabai and Dahuang,growth parameter values under 50% and 25% light intensity were higher than that under 100% and 5% light intensity.The specific leaf weight and root weight ratio generally showed decrease trends with the decrease of light intensity in all the three provenances,except that the specific leaf weight of Dahuang in 50% light intensity was higher than other light treatments.In short,the seedlings of three Aquilaria sinensis provenances could make a series of changes in morphology to adapt to the light environment; Yunnan provenance had the best growth in natural light (100%),while Dabai and Dahuang were more suitable in moderate light intensity(50%).%研究不同光处理(100%,50%,25%和5%自然光)对土沉香幼苗形态和解剖特征的影响,以了解土沉香幼苗叶片形态结构对光的适应规律.结果表明,不同光强对3个土沉香种源(大白、大黄和云南)的解剖结构和生长参数有不同程度

  6. Effect of adaptive threshold filtering on ultrasonic nakagami parameter to detect variation in scatterer concentration.

    Science.gov (United States)

    Tsui, Po-Hsiang; Wan, Yung-Liang; Huang, Chih-Chung; Wang, Ming-Chen

    2010-10-01

    The Nakagami parameter is associated with the Nakagami distribution estimated from ultrasonic backscattered signals and closely reflects the scatterer concentrations in tissues. There is an interest in exploring the possibility of enhancing the ability of the Nakagami parameter to characterize tissues. In this paper, we explore the effect of adaptive thresholdfiltering based on the noise-assisted empirical mode decomposition of the ultrasonic backscattered signals on the Nakagami parameter as a function of scatterer concentration for improving the Nakagami parameter performance. We carried out phantom experiments using 5 MHz focused and nonfocused transducers. Before filtering, the dynamic ranges of the Nakagami parameter, estimated using focused and nonfocused transducers between the scatterer concentrations of 2 and 32 scatterers/mm3, were 0.44 and 0.1, respectively. After filtering, the dynamic ranges of the Nakagami parameter, using the focused and nonfocused transducers, were 0.71 and 0.79, respectively. The experimental results showed that the adaptive threshold filter makes the Nakagami parameter measured by a focused transducer more sensitive to the variation in the scatterer concentration. The proposed method also endows the Nakagami parameter measured by a nonfocused transducer with the ability to differentiate various scatterer concentrations. However, the Nakagami parameters estimated by focused and nonfocused transducers after adaptive threshold filtering have different physical meanings: the former represents the statistics of signals backscattered from unresolvable scatterers while the latter is associated with stronger resolvable scatterers or local inhomogeneity due to scatterer aggregation.

  7. 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.

  8. Corticosterone metabolites in laying hen droppings-Effects of fiber enrichment, genotype, and daily variations.

    Science.gov (United States)

    Alm, M; Holm, L; Tauson, R; Wall, H

    2014-10-01

    There is growing interest and concern for animal welfare in commercial poultry production. To evaluate stress and welfare in an objective and noninvasive way, fecal corticosterone metabolites (FCM) in droppings can be analyzed. However, the influence of diet, genotype, and daily variations in FCM and production of droppings in laying hens has been poorly investigated. This study examined the effect of insoluble fiber by adding 3% ground straw pellets to the feed to Lohmann Selected Leghorn (LSL) and Lohmann Brown (LB) hens housed in furnished cages between 20 and 40 wk of age. In total, 960 hens were included in the study. Droppings were collected 4 times per day for 3 consecutive days and analyzed by corticosterone immunoassay. Biological validation confirmed the ability of the assay to detect changes in FCM levels. Inclusion of straw pellets in the feed increased FCM concentration in both hen genotypes and increased excretion rate of FCM in LB hens. The LB hens also produced greater amounts of droppings than LSL hens. Both FCM levels and production of droppings varied during the day, although no distinct diurnal rhythm was found. These findings demonstrate that when using FCM to evaluate stress and welfare in laying hens, many factors (e.g., diet, genotype used, and so on) need to be taken into account to allow accurate interpretation of the results. In addition, under certain conditions, excretion rate of FCM might be more appropriate to use compared with FCM concentration.

  9. Effect of Salinity Variations on the Performance of Activated Sludge System

    Institute of Scientific and Technical Information of China (English)

    JIAN-LONG WANG; XIN-MIN ZHAN; YE-CHENG FENG; YI QIAN

    2005-01-01

    Objective To investigate the influence of salinity variations on the performance of activated sludge systems, treating domestic wastewater. Methods The completely mixed reactor was used and operated in a batch-wise mode. The activated sludge taken from the Gaobeidian Wastewater Treatment Plant was used as a seeding sludge. Total organic carbon (TOC), oxygen uptake rate (OUR) and suspended solids (SS) were used as parameters to characterize the performance of the treatment systems. TOC was measured using a TOC-analyzer (TOC-5000, Japan). The OUR value was measured with a dissolved oxygen meter (YSI model-58). SS was measured gravimetrically. Results The TOC removal efficiency and the OUR value of activated sludge were not deteriorated when the NaCl shock concentration was less than 0.5 g/L. However, when the NaCl shock concentrations were up to 10g/L and 20 g/L, the OUR of activated sludge was reduced by 35% and TOC removal efficiency was dropped by 30%, compared with the control experiment without NaCl shock loading. Conclusion The effect of NaCl shock loading on the activated sludge wastewater treatment system is dependant upon the NaCl concentrations and the degree of influence can be inferred through the change of substrate utilization rate at different shock NaCl loadings.

  10. 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.

  11. 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.

  12. Varying Variation: The Effects of Within- Versus Across-Feature Differences on Relational Category Learning

    Directory of Open Access Journals (Sweden)

    Katherine Anne Livins

    2015-02-01

    Full Text Available Learning of feature-based categories is known to interact with feature-variation in a variety of ways, depending on the type of variation (e.g., Markman & Maddox, 2003. However, relational categories are distinct from feature-based categories in that they determine membership based on structural similarities. As a result, the way that they interact with feature variation is unclear. This paper explores both experimental and computational data and argues that, despite its reliance on structural factors, relational category-learning should still be affected by the type of feature variation present during the learning process. It specifically suggests that within-feature and across-feature variation should produce different learning trajectories due to a difference in representational cost. The paper then uses the DORA model (Doumas, Hummel, & Sandhofer, 2008 to discuss how this account might function in a cognitive system before presenting an experiment aimed at testing this account. The experiment was a relational category-learning task and was run on human participants and then simulated in DORA. Both sets of results indicated that learning a relational category from a training set with a lower amount of variation is easier, but that learning from a training set with increased within-feature variation is significantly less challenging than learning from a set with increased across-feature variation. These results sup-port the claim that, like feature-based category-learning, relational category-learning is sensitive to the type of feature variation in the training set.

  13. 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.

  14. The effect of variation in phased array element performance for Non-Destructive Evaluation (NDE).

    Science.gov (United States)

    Duxbury, David; Russell, Jonathan; Lowe, Michael

    2013-08-01

    This paper reports the results of an investigation into the effects of phased array element performance on ultrasonic beam integrity. This investigation has been performed using an array beam model based on Huygens' principle to independently investigate the effects of element sensitivity and phase, and non-functioning elements via Monte Carlo simulation. The purpose of this work is to allow a new method of array calibration for Non-Destructive Evaluation (NDE) to be adopted that focuses on probe integrity rather than beam integrity. This approach is better suited to component inspections that utilise Full Matrix Capture (FMC) to record data as the calibration routine is uncoupled from the beams that the array is required to produce. For this approach to be adopted specifications must be placed on element performance that guarantee beam quality without carrying out any beam forming. The principal result of this investigation is that the dominant outcome following variations in array element performance is the introduction of beam artefacts such as main beam broadening, raising of the noise floor of the ultrasonic field, and the enlargement or creation of side lobes. Specifications for practical allowable limits of element sensitivity, element phase, and the number of non-functioning elements have been suggested based on a minimum amplitude difference between beam artefacts and the main beam peak of 8 dB. Simulation at a number of centre frequencies has led to a recommendation that the product of transducer bandwidth and maximum phase error should be kept below 0.051 and 0.035 for focused and plane beams respectively. Element sensitivity should be within 50% of mean value of the aperture, and no more than 9% of the elements should be non-functioning.

  15. 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

  16. 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

  17. 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...

  18. Estimating the effect of income on health and mortality using lottery prizes as exogenous source of variation in income

    NARCIS (Netherlands)

    Lindahl, M.

    2003-01-01

    A vast literature has established a strong positive relation between income and health status and a negative relation with mortality. This paper studies the effects of income on health and mortality, using only the part of income variation due to a truly exogenous factor: monetary lottery prizes of

  19. 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

  20. 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

  1. The anatomical diaspora: evidence of early American anatomical traditions in North Dakota.

    Science.gov (United States)

    Stubblefield, Phoebe R

    2011-09-01

    The current focus in forensic anthropology on increasing scientific certainty in ancestry determination reinforces the need to examine the ancestry of skeletal remains used for osteology instruction. Human skeletal remains were discovered on the University of North Dakota campus in 2007. After recovery, the osteological examination resulted in a profile for a 33- to 46-year-old woman of African descent with stature ranging from 56.3 to 61.0 in. The pattern of postmortem damage indicated that the remains had been prepared for use as an anatomical teaching specimen. Review of the American history of anatomical teaching revealed a preference for Black subjects, which apparently extended to states like North Dakota despite extremely low resident populations of people of African descent. This study emphasizes the need to examine the ancestry of older teaching specimens that lack provenience, rather than assuming they are derived from typical (i.e., Indian) sources of anatomical material.

  2. 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

  3. 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

  4. 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

  5. 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).

  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. 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).

  8. 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).

  9. 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.

  10. Spatial variation in keystone effects: Small mammal diversity associated with black-tailed prairie dog colonies

    Science.gov (United States)

    Cully, J.F.; Collinge, S.K.; Van Nimwegen, R. E.; Ray, C.; Johnson, W.C.; Thiagarajan, B.; Conlin, D.B.; Holmes, B.E.

    2010-01-01

    Species with extensive geographic ranges may interact with different species assemblages at distant locations, with the result that the nature of the interactions may vary spatially. Black-tailed prairie dogs Cynomys ludovicianus occur from Canada to Mexico in grasslands of the western Great Plains of North America. Black-tailed prairie dogs alter vegetation and dig extensive burrow systems that alter grassland habitats for plants and other animal species. These alterations of habitat justify the descriptor " ecological engineer," and the resulting changes in species composition have earned them status as a keystone species. We examined the impact of black-tailed prairie dogs on small mammal assemblages by trapping at on- and off-colony locations at eight study areas across the species' geographic range. We posed 2 nested hypotheses: 1) prairie dogs function as a keystone species for other rodent species; and 2) the keystone role varies spatially. Assuming that it does, we asked what are the sources of the variation? Black-tailed prairie dogs consistently functioned as a keystone species in that there were strong statistically significant differences in community composition on versus off prairie dog colonies across the species range in prairie grassland. Small mammal species composition varied along both latitudinal and longitudinal gradients, and species richness varied from 4 to 11. Assemblages closer together were more similar; such correlations approximately doubled when including only on- or off-colony grids. Black-tailed prairie dogs had a significant effect on associated rodent assemblages that varied regionally, dependent upon the composition of the local rodent species pool. Over the range of the black-tailed prairie dog, on-colony rodent richness and evenness were less variable, and species composition was more consistent than off-colony assemblages. ?? 2010 The Authors.

  11. 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.

  12. 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.

  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. Construction and biomechanical properties of polyaxial self-locking anatomical plate based on the geometry of distal tibia.

    Science.gov (United States)

    Liang, Weiguo; Ye, Weixiong; Ye, Dongping; Zhou, Ziqiang; Chen, Zhiguang; Li, Aiguo; Xie, Zong-Han; Zhang, Lihai; Xu, Jiake

    2014-01-01

    In order to provide scientific and empirical evidence for the clinical application of the polyaxial self-locking anatomical plate, 80 human tibias from healthy adults were scanned by spiral CT and their three-dimensional images were reconstructed using the surface shaded display (SSD) method. Firstly, based on the geometric data of distal tibia, a polyaxial self-locking anatomical plate for distal tibia was designed and constructed. Biomechanical tests were then performed by applying axial loading, 4-point bending, and axial torsion loading on the fracture fixation models of fresh cadaver tibias. Our results showed that variation in twisting angles of lateral tibia surface was found in various segments of the distal tibia. The polyaxial self-locking anatomical plate was constructed based on the geometry of the distal tibia. Compared to the conventional anatomical locking plate, the polyaxial self-locking anatomical plate of the distal tibia provides a better fit to the geometry of the distal tibia of the domestic population, and the insertion angle of locking screws can be regulated up to 30°. Collectively, this study assesses the geometry of the distal tibia and provides variable locking screw trajectory to improve screw-plate stability through the design of a polyaxial self-locking anatomical plate.

  15. INVESTIGATION OF SYSTEMATIC EFFECTS IN KEPLER DATA: SEASONAL VARIATIONS IN THE LIGHT CURVE OF HAT-P-7b

    Energy Technology Data Exchange (ETDEWEB)

    Van Eylen, V.; Lindholm Nielsen, M.; Hinrup, B.; Tingley, B.; Kjeldsen, H., E-mail: vincent@phys.au.dk [Stellar Astrophysics Centre, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C (Denmark)

    2013-09-10

    With years of Kepler data currently available, the measurement of variations in planetary transit depths over time can now be attempted. To do so, it is of primary importance to understand which systematic effects may affect the measurement of transits. We aim to measure the stability of Kepler measurements over years of observations. We present a study of the depth of about 500 transit events of the Hot Jupiter HAT-P-7b, using 14 quarters (Q0-Q13) of data from the Kepler satellite. We find a systematic variation in the depth of the primary transit, related to quarters of data and recurring yearly. These seasonal variations are about 1%. Within seasons, we find no evidence for trends. We speculate that the cause of the seasonal variations could be unknown field crowding or instrumental artifacts. Our results show that care must be taken when combining transits throughout different quarters of Kepler data. Measuring the relative planetary radius of HAT-P-7b without taking these systematic effects into account leads to unrealistically low error estimates. This effect could be present in all Kepler targets. If so, relative radius measurements of all Hot Jupiters to a precision much better than 1% are unrealistic.

  16. 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.

  17. 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.

  18. 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 .

  19. Seed size variation in the palm Euterpe edulis and the effects of seed predators on germination and seedling survival

    Science.gov (United States)

    Pizo, Marco A.; Von Allmen, Christiane; Morellato, L. Patricia C.

    2006-05-01

    Intraspecific variation in seed size is common in wild plant populations and has important consequences for the reproductive success of individual plants. Multiple, often conflicting evolutionary forces mediated by biotic as well as abiotic agents may maintain such a variation. In this paper we assessed seed size variation in a population of the threatened, commercially important palm Euterpe edulis in southeast Brazil. We investigated (i) how this variation affects the probability of attack by vertebrate and invertebrate post-dispersal seed predators, and (ii) if seed size influences the outcome of seeds damaged by beetles in terms of seed germination and early survival of seedlings. Euterpe edulis seeds varied in diameter from 8.3 to 14.1 mm. Neither insects nor rodents selected the seeds they preyed upon based on seed size. Seed germination and total, shoot and root biomasses of one-year seedlings were significantly and positively affected by seed size. Root biomass and seedling survival were negatively affected by seed damage caused by a scolytid beetle ( Coccotrypes palmarum) whose adults bore into seeds to consume part of the endosperm, but do not oviposit on them. Seed size had a marginally significant effect on seedling survival. Therefore, if any advantage is accrued by E. edulis individuals producing large seeds, this is because of greater seed germination success and seedling vigor. If this is so, even a relatively narrow range of variation in seed size as observed in the E. edulis population studied may translate into differential success of individual plants.

  20. Environmental effects on the shape variation of male ultraviolet patterns in the Brimstone butterfly ( Gonepteryx rhamni, Pieridae, Lepidoptera)

    Science.gov (United States)

    Pecháček, Pavel; Stella, David; Keil, Petr; Kleisner, Karel

    2014-12-01

    The males of the Brimstone butterfly ( Gonepteryx rhamni) have ultraviolet pattern on the dorsal surfaces of their wings. Using geometric morphometrics, we have analysed correlations between environmental variables (climate, productivity) and shape variability of the ultraviolet pattern and the forewing in 110 male specimens of G. rhamni collected in the Palaearctic zone. To start with, we subjected the environmental variables to principal component analysis (PCA). The first PCA axis (precipitation, temperature, latitude) significantly correlated with shape variation of the ultraviolet patterns across the Palaearctic. Additionally, we have performed two-block partial least squares (PLS) analysis to assess co-variation between intraspecific shape variation and the variation of 11 environmental variables. The first PLS axis explained 93 % of variability and represented the effect of precipitation, temperature and latitude. Along this axis, we observed a systematic increase in the relative area of ultraviolet colouration with increasing temperature and precipitation and decreasing latitude. We conclude that the shape variation of ultraviolet patterns on the forewings of male Brimstones is correlated with large-scale environmental factors.

  1. 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

  2. Effects of variation of environmental parameters on the performance of Resistive Plate Chamber detectors

    Energy Technology Data Exchange (ETDEWEB)

    Meghna, K.K. [INO Graduate Training Programme and Saha Institute of Nuclear Physics, Kolkata 700064 (India); Homi Bhabha National Institute, Mumbai 400085 (India); Biswas, S. [School of Physical Sciences, National Institute of Science Education and Research, Bhubaneswar 751005 (India); Jash, A. [INO Graduate Training Programme and Saha Institute of Nuclear Physics, Kolkata 700064 (India); Homi Bhabha National Institute, Mumbai 400085 (India); Chattopadhyay, S. [Variable Energy Cyclotron Centre, Kolkata 700064 (India); Homi Bhabha National Institute, Mumbai 400085 (India); Saha, S., E-mail: satyajit.saha@saha.ac.in [Applied Nuclear Physics Division, Saha Institute of Nuclear Physics, Kolkata 700064 (India); Homi Bhabha National Institute, Mumbai 400085 (India)

    2016-04-21

    Performance of single gap Resistive Plate Chamber (RPC) detectors is investigated under variation of environmental parameters, such as temperature and relative humidity. Operational characteristics of the RPCs depend on both the environmental temperature and the relative humidity. Sensitivity to such dependence is found to be more on temperature rather than the relative humidity. Qualitative interpretation of some of the results obtained is given based on the known properties of the electrode materials and gases used in the detectors. - Highlights: • Performance of single gap bakelite Resistive Plate Chamber (RPC) detectors is investigated under independent variation of environmental temperature and relative humidity. • Parameters such as leakage currents, noise rates, efficiency and timing characteristics of RPCs are investigated. • Operational characteristics of the RPCs depend on both the environmental temperature and the relative humidity. • Sensitivity of the operational parameters to variation of environmental parameters is found to be more on temperature rather than the relative humidity.

  3. 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.

  4. Anatomic Optical Coherence Tomography of Upper Airways

    Science.gov (United States)

    Chin Loy, Anthony; Jing, Joseph; Zhang, Jun; Wang, Yong; Elghobashi, Said; Chen, Zhongping; Wong, Brian J. F.

    The upper airway is a complex and intricate system responsible for respiration, phonation, and deglutition. Obstruction of the upper airways afflicts an estimated 12-18 million Americans. Pharyngeal size and shape are important factors in the pathogenesis of airway obstructions. In addition, nocturnal loss in pharyngeal muscular tone combined with high pharyngeal resistance can lead to collapse of the airway and periodic partial or complete upper airway obstruction. Anatomical optical coherence tomography (OCT) has the potential to provide high-speed three-dimensional tomographic images of the airway lumen without the use of ionizing radiation. In this chapter we describe the methods behind endoscopic OCT imaging and processing to generate full three dimensional anatomical models of the human airway which can be used in conjunction with numerical simulation methods to assess areas of airway obstruction. Combining this structural information with flow dynamic simulations, we can better estimate the site and causes of airway obstruction and better select and design surgery for patients with obstructive sleep apnea.

  5. Retinal vascular tree reconstruction with anatomical realism.

    Science.gov (United States)

    Lin, Kai-Shun; Tsai, Chia-Ling; Tsai, Chih-Hsiangng; Sofka, Michal; Chen, Shih-Jen; Lin, Wei-Yang

    2012-12-01

    Motivated by the goals of automatically extracting vessel segments and constructing retinal vascular trees with anatomical realism, this paper presents and analyses an algorithm that combines vessel segmentation and grouping of the extracted vessel segments. The proposed method aims to restore the topology of the vascular trees with anatomical realism for clinical studies and diagnosis of retinal vascular diseases, which manifest abnormalities in either venous and/or arterial vascular systems. Vessel segments are grouped using extended Kalman filter which takes into account continuities in curvature, width, and intensity changes at the bifurcation or crossover point. At a junction, the proposed method applies the minimum-cost matching algorithm to resolve the conflict in grouping due to error in tracing. The system was trained with 20 images from the DRIVE dataset, and tested using the remaining 20 images. The dataset contained a mixture of normal and pathological images. In addition, six pathological fluorescein angiogram sequences were also included in this study. The results were compared against the groundtruth images provided by a physician, achieving average success rates of 88.79% and 90.09%, respectively.

  6. Anatomical considerations to prevent facial nerve injury.

    Science.gov (United States)

    Roostaeian, Jason; Rohrich, Rod J; Stuzin, James M

    2015-05-01

    Injury to the facial nerve during a face lift is a relatively rare but serious complication. A large body of literature has been dedicated toward bettering the understanding of the anatomical course of the facial nerve and the relative danger zones. Most of these prior reports, however, have focused on identifying the location of facial nerve branches based on their trajectory mostly in two dimensions and rarely in three dimensions. Unfortunately, the exact location of the facial nerve relative to palpable or visible facial landmarks is quite variable. Although the precise location of facial nerve branches is variable, its relationship to soft-tissue planes is relatively constant. The focus of this report is to improve understanding of facial soft-tissue anatomy so that safe planes of dissection during surgical undermining may be identified for each branch of the facial nerve. Certain anatomical locations more prone to injury and high-risk patient parameters are further emphasized to help minimize the risk of facial nerve injury during rhytidectomy.

  7. 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

  8. Anatomic structural study of cerebellopontine angle via endoscope

    Institute of Scientific and Technical Information of China (English)

    XIA Yin; LI Xi-ping; HAN De-min; ZHENG Jun; LONG Hai-shan; SHI Jin-feng

    2007-01-01

    Background Minimally invasive surgery in skull base relying on searching for possible anatomic basis for endoscopic technology is controversial. The objective of this study was to observe the spatial relationships between main blood vessels and nerves in the cerebellopontine angle area and provide anatomic basis for lateral and posterior skull base minimally invasive surgery via endoscopic retrosigmoid keyhole approach.Methods This study was conducted on thirty dried adult skulls to measure the spatial relationships among the surface bony marks of posterior cranial fossa, and to locate the most appropriate drilling area for retrosigmoid keyhole approach.In addition, we used 10 formaldehyde-fixed adult cadaver specimens for simulating endoscopic retrosigmoid approach to determine the visible scope.Results The midpoint between the mastoid tip and the asterion was the best drilling point for retrosigmoid approach. A hole centered on this point with the 2.0 cm in diameter was suitable for exposing the related structures in the cerebellopontine angle. Retrosigmoid keyhole approach can decrease the pressure on the cerebellum and expose the related structures effectively which include facial nerve, vestibulocochlear nerve, trigeminal nerve, glossopharyngeal nerve, vagus nerve, accessory nerve, hypoglossal nerve, anterior inferior cerebellar artery, posterior inferior cerebellar artery and labyrinthine artery, etc.Conclusions Exact location on endoscope retrosigmoid approach can avoid dragging cerebellum during the minimally invasive surgery. The application of retrosigmoid keyhole approach will extend the application of endoscopic technology.

  9. Assessment of anatomical knowledge: Approaches taken by higher education institutions.

    Science.gov (United States)

    Choudhury, Bipasha; Freemont, Anthony

    2017-04-01

    Assessment serves the primary function of determining a student's competence in a subject. Several different assessment formats are available for assessing anatomical skills, knowledge and understanding and, as assessment can drive learning, a careful selection of assessments can help to engender the correct deep learning facility required of the safe clinical practitioner. The aim of this review was to survey the published literature to see whether higher education institutions are taking an andragogical approach to assessment. Five databases (EMBASE, ERIC, Medline, PubMed, and Web of Knowledge) were searched using standardized search terms with two limits applied (English language, and 2000 to the present). Among the 2,094 papers found, 32 were deemed suitable for this review. Current literature on assessment can be categorized into the following themes: assessment driven learning, types of assessments, frequency of assessments, and use of images in assessments. The consensus is to use a variety of methods, written and practical, to assess anatomical knowledge and skill in different domains. Institutions aim for different levels of Bloom's taxonomy for students at similar stages of their medical degree. Formative assessments are used widely, in differing formats, with mostly good effects on the final examination grade. In conclusion, a wide variety of assessments, each aimed at a different level of Bloom's taxonomy, are used by different institutions. Clin. Anat. 30:290-299, 2017. © 2017 Wiley Periodicals, Inc.

  10. 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.

  11. The effect of microstructural variation on the mechanical and acoustic properties of silicon carbide

    Science.gov (United States)

    Slusark, Douglas Michael

    Silicon carbide ceramic materials have many beneficial properties which have led to their adoption in various industrial uses, including its application as an armor material. This is due to the high hardness and stiffness of these materials, as well as a low relative density. The homogeneity of the final properties depends upon the processing history of the material. Factors which affect this include the need for high temperatures and sintering additives to achieve densification, as well as the presence of additive agglomerates and pressing artifacts within the green compact. This dissertation seeks to determine the effect which microstructural variability has on the acoustic and mechanical properties of sintered silicon carbide materials. Sample sets examined included commercially produced, pressurelessly sintered tiles, as well as additional, targeted tiles which were specifically produced for evaluation in this study. Production of these targeted samples was carried out such that particular aspects of the microstructure were emphasized. These included tiles which were fired with an excess of boron sintering aid as well as tiles which had been pressed to a reduced green body density and then fired. The sample evaluation procedure which was developed incorporated non destructive evaluation methods, mechanical testing, and both fractographic and image analysis of fractured and polished sections. Non destructive evaluation of the tiles was carried out by Archimedes density and ultrasound scanning at 20 MHz to determine the acoustic attenuation coefficient. Selected samples were chosen for machining into ASTM B-type bend bars on which 4-pt flexure testing was performed. Strength limiting features were designated for each sample set. The correlation between acoustic attenuation coefficient and quasi-static strength was examined both qualitatively and quantitatively. This was done by comparing the primary fracture location of flexure bars to features within the

  12. 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

  13. 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

  14. Review: the effects of secular variation in seawater Mg/Ca on marine biocalcification

    Science.gov (United States)

    Ries, J. B.

    2009-07-01

    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"; 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/Ca2=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 seawater Mg/Ca, a probable consequence of them inducing a less controlled mode of calcification simply through the removal of CO2 via photosynthesis. This body of work also has implications for thermal

  15. Interpreting variation in growth of Eurasian Spoonbill chicks: disentangling the effects of age, sex and environment

    NARCIS (Netherlands)

    Lok, T.; Overdijk, O.; Piersma, T.

    2014-01-01

    Chick body condition can be a sensitive indicator of local environmental conditions and has been shown to be correlated with chick survival. Designing a reliable index of chick body condition for a given species from a single measurement point requires knowledge about the extent of variation in body

  16. The Effect of Scene Variation on the Redundant Use of Color in Definite Reference

    Science.gov (United States)

    Koolen, Ruud; Goudbeek, Martijn; Krahmer, Emiel

    2013-01-01

    This study investigates to what extent the amount of variation in a visual scene causes speakers to mention the attribute color in their definite target descriptions, focusing on scenes in which this attribute is not needed for identification of the target. The results of our three experiments show that speakers are more likely to redundantly…

  17. Effective Normalization for Copy Number Variation Detection from Whole Genome Sequencing

    NARCIS (Netherlands)

    Janevski, A.; Varadan, V.; Kamalakaran, S.; Banerjee, N.; Dimitrova, D.

    2012-01-01

    Background Whole genome sequencing enables a high resolution view ofthe human genome and provides unique insights into genome structureat an unprecedented scale. There have been a number of tools to infer copy number variation in the genome. These tools while validatedalso include a number of parame

  18. Effects of local variation in nitrogen deposition on butterfly trends in The Netherlands

    NARCIS (Netherlands)

    Wallis de Vries, M.F.; Swaay, van C.A.M.

    2013-01-01

    Anthropogenic nitrogen deposition has been recognized as a factor affecting the dynamics and composition of plant communities. Its impact on insect communities is still largely unknown. Using data from the Dutch Butterfly Monitoring Scheme, we analyzed the variation in local trends of butterfly abun

  19. 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.

  20. Sex Variations in Youth Anxiety Symptoms: Effects of Pubertal Development and Gender Role Orientation

    Science.gov (United States)

    Carter, Rona; Silverman, Wendy K.; Jaccard, James

    2011-01-01

    This study evaluated whether pubertal development and gender role orientation (i.e., masculinity and femininity) can partially explain sex variations in youth anxiety symptoms among clinic-referred anxious youth (N = 175; ages 9-13 years; 74% Hispanic; 48% female). Using youth and parent ratings of youth anxiety symptoms, structural equation…

  1. The Effective Comparisons of Tibial Distal Anatomical Steel Plates on Treating Intertrochanteric Fractures of the Middle and Lower Segment of Tibia%胫骨远端解剖钢板治疗胫骨中下段骨折疗效比较

    Institute of Scientific and Technical Information of China (English)

    刘跃华; 陈岩; 李亚非

    2015-01-01

    Objective The aim of this thesis is to make comparisons and analysis of the clinical effect between tibial distal medial anatomical steel plate and tibial distal anterolateral anatomical steel plate on treating fractures of the middle and lower segment of tibia.MethodsThe research method was to divide the 60 patients with fractures of the middle and lower segment of tibia into 2 groups according to different treating ways: one with tibial distal medial anatomical steel plate, the other with tibial distal anterolateral anatomical steel plate. The author applied operation time, intraoperative blood loss, fracture healing time, the rate of delayed healing of incision, fracture of the steel plate and bone nonunion as the indexes of clinical evaluation and evaluated the postoperative limb function on the base of Johner - Wruhs joint function evaluation standard. And the results were analyzed by statistical software SPSS13.0.ResultsThere was no statistical difference in operation time, intraoperative blood loss and fracture healing time, (P>0. 05); the rate of delayed healing of incision, fracture of the steel plate and bone nonunion was a little higher in the group with tibial distal anterolateral anatomical steel plate, but there was no statistical difference, (P>0. 05); According to the Johner - Wruhs evaluation, there was signiifcant difference in limb function recovery between the two groups.Conclusion Therefore, the conclusion of this thesis is that applying tibial distal medial anatomical steel plate on treating fractures of the middle and lower segment of tibia could get more desired effect, which is really worth promoting.%目的:应用胫骨远端内侧解剖钢板和胫骨远端前外侧解剖钢板治疗胫骨中下段骨折,对2种方法的临床疗效进行比较分析。方法63例胫骨中下段骨折患者按治疗方法不同,依次分为A组即胫骨远端内侧解剖钢板组和B组即胫骨远端前外侧解剖钢板组,分别以手术时间

  2. 不同盐梯度处理下沼泽小叶桦的生理特征及叶片结构%Photosynthetic Performance and Variation in Leaf Anatomic Structure of Betula microphylla var.paludosa under Different Saline Conditions