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Sample records for anatomical variation effect

  1. Anatomical variations of the proximal radius and their effects on osteosynthesis.

    Science.gov (United States)

    Giannicola, Giuseppe; Manauzzi, Erica; Sacchetti, Federico M; Greco, Alessandro; Bullitta, Gianluca; Vestri, Annarita; Cinotti, Gianluca

    2012-05-01

    In fractures of the radial head and neck requiring open reduction and internal fixation, osteosynthesis may be safely applied in a limited zone. We conducted a morphometric study of the proximal radius at the level of the safe zone to identify different morphologic types of this anatomical region. We analyzed 44 dried cadaveric radii. We measured the whole length of the radius, the length of the neck and head, and the minimum and maximum diameter of the radial head. The morphologic aspect of the neck-head curvature of the safe zone was evaluated qualitatively and quantitatively. The proximal radius at the level of the safe zone exhibited different radii of bending. In particular, we identified a morphologic type A, which showed a flat profile (25% of cases), morphologic types B and C, which showed a low concave curvature (64%), and a marked concave curvature (11%), respectively, of the safe zone. The profile of the proximal radius in the safe zone shows substantial morphologic variations that should be taken into account when operating on fractures of the proximal radius, to avoid malunions, pain, and stiffness of the elbow joint. A preoperative radiograph of the contralateral uninjured radius may be helpful in selecting the most appropriate internal fixation device to reconstruct the proximal radius after comminuted fractures. Knowledge of the proper bending radius of the safe zone allows the surgeon to select the most appropriate plate, and to achieve good fracture reduction and anatomical restoration of the proximal radius. Copyright © 2012 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  2. Effects of anatomical variation on trainee performance in a virtual reality temporal bone surgery simulator.

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    Piromchai, P; Ioannou, I; Wijewickrema, S; Kasemsiri, P; Lodge, J; Kennedy, G; O'Leary, S

    2017-01-01

    To investigate the importance of anatomical variation in acquiring skills in virtual reality cochlear implant surgery. Eleven otolaryngology residents participated in this study. They were randomly allocated to practice cochlear implant surgery on the same specimen or on different specimens for four weeks. They were then tested on two new specimens, one standard and one challenging. Videos of their performance were de-identified and reviewed independently, by two blinded consultant otolaryngologists, using a validated assessment scale. The scores were compared between groups. On the standard specimen, the round window preparation score was 2.7 ± 0.4 for the experimental group and 1.7 ± 0.6 for the control group (p = 0.01). On the challenging specimen, instrument handling and facial nerve preservation scores of the experimental group were 3.0 ± 0.4 and 3.5 ± 0.7 respectively, while the control group received scores of 2.1 ± 0.8 and 2.4 ± 0.9 respectively (p anatomies is beneficial in the development of expertise.

  3. The effect of catheter displacement and anatomical variations on the dose distribution in MRI-guided focal HDR brachytherapy for prostate cancer

    NARCIS (Netherlands)

    Maenhout, Metha; van der Voort van Zyp, Jochem R N; Borot, Maxence; Peters, Max; van Vulpen, Marco; van den Bosch, Maurice; Moerland, Rien

    PURPOSE: The aim of this study was to analyze the effect of catheter displacement and anatomical variations of prostate and organs at risk on dose distribution in MRI-guided 19 Gy single fraction focal high-dose-rate brachytherapy (HDR-BT) of the prostate. METHODS AND MATERIALS: Seventeen patients

  4. Role of anatomic variations of paranasal sinuses on the prevalence ...

    African Journals Online (AJOL)

    Objective: The aim of this study was to determine the frequency of anatomic variations of the paranasal sinuses and their roles in the development of sinusitis. Materials and Methods: Computed tomography of paranasal sinuses of 350 patients was assessed in terms of anatomic variations and inflammatory sinus pathology.

  5. Role of Anatomic Variations of Paranasal Sinuses on the ...

    African Journals Online (AJOL)

    2017-05-09

    May 9, 2017 ... pathology. The coexistence of anatomic variations with sinusitis was statistically investigated.Results: At least one anatomical variation of paranasal sinuses was detected in 325 patients ... area, hardly evaluated regions of sinonasal pathologies ..... formation. Optic nerve and extraorbital muscle damage.

  6. Tinkering and the Origins of Heritable Anatomical Variation in Vertebrates

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    Jonathan B. L. Bard

    2018-02-01

    Full Text Available Evolutionary change comes from natural and other forms of selection acting on existing anatomical and physiological variants. While much is known about selection, little is known about the details of how genetic mutation leads to the range of heritable anatomical variants that are present within any population. This paper takes a systems-based view to explore how genomic mutation in vertebrate genomes works its way upwards, though changes to proteins, protein networks, and cell phenotypes to produce variants in anatomical detail. The evidence used in this approach mainly derives from analysing anatomical change in adult vertebrates and the protein networks that drive tissue formation in embryos. The former indicate which processes drive variation—these are mainly patterning, timing, and growth—and the latter their molecular basis. The paper then examines the effects of mutation and genetic drift on these processes, the nature of the resulting heritable phenotypic variation within a population, and the experimental evidence on the speed with which new variants can appear under selection. The discussion considers whether this speed is adequate to explain the observed rate of evolutionary change or whether other non-canonical, adaptive mechanisms of heritable mutation are needed. The evidence to hand suggests that they are not, for vertebrate evolution at least.

  7. Corona mortis: an anatomical variation with clinical relevance. Case report.

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    Guillermo Adrián Rivera-Cardona

    2010-12-01

    Full Text Available The obturator artery is one of the parietal branches arising from the internal iliac artery, the anatomical variation from which this artery originates is called “The corona mortis”, generally from the external iliac artery or the inferior epigastric artery. This finding was observed bilaterally in a male cadaver during a pelvis dissection. Clinical consideration of the anatomical variation in the obturator artery, during surgical procedures, is of great importance due to the risk of pelvic hemorrhage.

  8. Anatomical variations of the brachial plexus terminal branches in ...

    African Journals Online (AJOL)

    Anatomical variations are clinically significant, but many are inadequately described or quantified. Variations in anatomy of the brachial plexus are important to surgeons and anesthesiologists performing surgical procedures in the neck, axilla and upper limb regions. It is also important for radiologists who interpret plain and ...

  9. Variations in the Anatomical Structures of the Guyon Canal.

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    Fadel, Zahir T; Samargandi, Osama A; Tang, David T

    2017-05-01

    Compression neuropathy of the ulnar nerve at the Guyon canal is commonly seen by hand surgeons. Different anatomical variations of structures related to the Guyon canal have been reported in the literature. A thorough knowledge of the normal contents and possible variations is essential during surgery and exploration. To review the recognized anatomical variations within and around the Guyon canal. This study is a narrative review in which relevant papers, clinical studies, and anatomical studies were selected by searching electronic databases (PubMed and EMBASE). Extensive manual review of references of the included studies was performed. We also describe a case report of an aberrant muscle crossing the Guyon canal. This study identified several variations in the anatomical structures of the Guyon canal reported in the literature. Variations of the ulnar nerve involved its course, branching pattern, deep motor branch, superficial sensory branch, dorsal cutaneous branch, and the communication with the median nerve. Ulnar artery variations involved its course, branching pattern, the superficial ulnar artery, and the dorsal perforating artery. Aberrant muscles crossing the Guyon canal were found to originate from the antebrachial fascia, pisiform bone, flexor retinaculum, the tendon of palmaris longus, flexor carpi ulnaris, or flexor carpi radialis; these muscles usually fuse with the hypothenar group. The diverse variations of the contents of the Guyon canal were adequately described in the literature. Taking these variations into consideration is important in preventing clinical misinterpretation and avoiding potential surgical complications.

  10. Anatomical Variation in the Wall Thickness of Wood Fibres of ...

    African Journals Online (AJOL)

    The wall thickness of wood fibres of rubber (Hevea brasiliensis) grown and tapped for latex in south eastern Nigeria were investigated to determine anatomical variation. The rubber trees which were overmature for tapping and keeping were sampled in hierarchical order of plantations, bud classes, trees, discs, cardinal ...

  11. Ethmomaxillary sinus: a particular anatomic variation of the paranasal sinuses

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    Sirikci, Akif; Bayram, Metin [Department of Radiology, Faculty of Medicine, Gaziantep University, Kolejtepe, 27310, Gaziantep (Turkey); Bayazit, Y.A.; Kanlikama, Muzaffer [Department of Otorhinolaryngology and Head and Neck Surgery, Faculty of Medicine, Gaziantep University, Kolejtepe, 27310, Gaziantep (Turkey)

    2004-02-01

    We assessed the morphological and radiological characteristics of ethmomaxillary sinus (EMS), which is an enlarged posterior ethmoidal air cell occupying the superior portion of the maxillary sinus while draining into superior meatus. This study is based on 1450 patients submitted to CT examination of the paranasal sinuses between 1998 and 2002. Sequential CT scans were obtained in the coronal plane in all the patients with 2.5- to 5-mm section thickness and were evaluated for EMS. The diagnosis of EMS was made when there was a posterior ethmoidal cell occupying the superior part of the maxillary sinus while draining to the superior meatus. When EMS was diagnosed, the morphology of the septum between the and maxillary sinus, and width of the superior meatus, were noted. The EMS was found in 10 of 1450 (0.7%) patients. The coexisting anatomic variations were concha bullosa (50%), upper concha pneumatization (20%), maxillary sinus hypoplasia (20%), uncinate bulla (10%), hypertrophied inferior concha (10%), paradoxic middle concha (10%), and septate maxillary sinus (10%). There was no relation between EMS and sinus disease. The EMS is a rare anatomic variation and does not appear to be associated with sinusitis. The EMS is not a well-studied anatomic variation, and the literature is lacking adequate information about this anatomic variation. This study performed in a large series of patients will possibly contribute to better understanding of this particular anomaly. (orig.)

  12. Gross Anatomical Variations and Congenital Anomalies of Surgical ...

    African Journals Online (AJOL)

    Results: A wide range of Anatomical variations of surgical importance were noted among the Ugandan cadavers. In 5% of the cases, the common hepatic artery originated from the superior Mesenteric artery. The course of the cystic artery in 61.9% of the cases was anterior to the right hepatic duct, in 31% it passed anterior ...

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

    International Nuclear Information System (INIS)

    Villela, Caroline Laurita Batista Couto; Gomes, Natalia Delage; Gaiotti, Juliana Oggioni; Costa, Ana Maria Doffemond; Ribeiro, Marcelo Almeida; Motta, Emilia Guerra Pinto Coelho; Moreira, Wanderval; Ramos, Laura Filgueiras Mourao; Diniz, Renata Lopes Furletti Caldeira

    2012-01-01

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

  14. Learning-based stochastic object models for characterizing anatomical variations

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    Dolly, Steven R.; Lou, Yang; Anastasio, Mark A.; Li, Hua

    2018-03-01

    It is widely known that the optimization of imaging systems based on objective, task-based measures of image quality via computer-simulation requires the use of a stochastic object model (SOM). However, the development of computationally tractable SOMs that can accurately model the statistical variations in human anatomy within a specified ensemble of patients remains a challenging task. Previously reported numerical anatomic models lack the ability to accurately model inter-patient and inter-organ variations in human anatomy among a broad patient population, mainly because they are established on image data corresponding to a few of patients and individual anatomic organs. This may introduce phantom-specific bias into computer-simulation studies, where the study result is heavily dependent on which phantom is used. In certain applications, however, databases of high-quality volumetric images and organ contours are available that can facilitate this SOM development. In this work, a novel and tractable methodology for learning a SOM and generating numerical phantoms from a set of volumetric training images is developed. The proposed methodology learns geometric attribute distributions (GAD) of human anatomic organs from a broad patient population, which characterize both centroid relationships between neighboring organs and anatomic shape similarity of individual organs among patients. By randomly sampling the learned centroid and shape GADs with the constraints of the respective principal attribute variations learned from the training data, an ensemble of stochastic objects can be created. The randomness in organ shape and position reflects the learned variability of human anatomy. To demonstrate the methodology, a SOM of an adult male pelvis is computed and examples of corresponding numerical phantoms are created.

  15. The effect of catheter displacement and anatomical variations on the dose distribution in MRI-guided focal HDR brachytherapy for prostate cancer.

    Science.gov (United States)

    Maenhout, Metha; van der Voort van Zyp, Jochem R N; Borot de Battisti, Maxence; Peters, Max; van Vulpen, Marco; van den Bosch, Maurice; Moerland, Marinus A

    The aim of this study was to analyze the effect of catheter displacement and anatomical variations of prostate and organs at risk on dose distribution in MRI-guided 19 Gy single fraction focal high-dose-rate brachytherapy (HDR-BT) of the prostate. Seventeen patients with localized prostate cancer were enrolled in a prospective trial investigating focal HDR-BT in a 1.5 T MRI-HDR-BT facility. The diagnostic MRI delineations were registered with intraoperative MR scan, and a single fraction of 19 Gy was applied to the visible tumor. Self-anchoring umbrella catheters were used for HDR-BT delivery. A 1.5 T MRI was performed directly after ultrasound (US)-guided catheter placement for treatment planning. After treatment and before removal of catheters, a posttreatment 1.5 T MRI was performed. Regions of interest were also delineated on the posttreatment MR images and the catheters of 17 patients were reconstructed. The dose plan was constructed for the posttreatment MRI scan to assess the influence of catheter migration and anatomical variation on the dose delivered to the target and the organs at risk. Also on the posttreatment MRI, the complete catheter reconstruction was reassessed, to correct for, for example, bending of the catheters. The displacement of catheters between the MRI scans was determined by comparing the catheter tip positions on the treatment planning and posttreatment 1.5 T MRI scans. The displacements of 241 catheters were investigated. Average (range) displacements of the umbrella catheters are 0.6 (0-2.9) mm in the x-direction, 0.5 (0-2.1) mm in the y-direction, and 0.9 (0-5.5) mm in the z-direction. In 3 patients, the displacement was >4 mm and up to 5.5 mm. This occurred in respectively 1/13, 1/16, and 1/18 catheters in these patients. The dosimetric differences between the intraoperative treatment and the posttreatment plans were in most patients less than 1.5 Gy. In 4 patients, a dose difference in clinical target volume D95 of >2

  16. Anatomical Variations of the Circulus Arteriosus in Cadaveric Human Brains

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    S. A. Gunnal

    2014-01-01

    Full Text Available Objective. Circulus arteriosus/circle of Willis (CW is a polygonal anastomotic channel at the base of the brain which unites the internal carotid and vertebrobasilar system. It maintains the steady and constant supply to the brain. The variations of CW are seen often. The Aim of the present work is to find out the percentage of normal pattern of CW, and the frequency of variations of the CW and to study the morphological and morphometric aspects of all components of CW. Methods. Circulus arteriosus of 150 formalin preserved brains were dissected. Dimensions of all the components forming circles were measured. Variations of all the segments were noted and well photographed. The variations such as aplasia, hypoplasia, duplication, fenestrations, and difference in dimensions with opposite segments were noted. The data collected in the study was analyzed. Results. Twenty-one different types of CW were found in the present study. Normal and complete CW was found in 60%. CW with gross morphological variations was seen in 40%. Maximum variations were seen in the PCoA followed by the ACoA in 50% and 40%, respectively. Conclusion. As it confirms high percentage of variations, all surgical interventions should be preceded by angiography. Awareness of these anatomical variations is important in neurovascular procedures.

  17. 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.

  18. Unilateral Duplication Of Parotid Duct. A Rare Anatomical Variation

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    Humberto Ferreira Arquez

    2017-11-01

    Full Text Available Background: The paired parotid glands are the largest of the major salivary glands and produces mainly serous secretions. The secretion of this gland reaches the oral cavity through single parotid duct (Stensen’s duct. The parotid duct begins at the anterior border of the gland, crosses the masseter muscle, and then pierces the buccinator muscle to reach the mucosa lining the mouth at the level of the cheek. The purpose of this study is determine the morphologic features of the parotid duct and describe an anatomical variation until now unreported. Methods and Findings: A total of 17 cadavers were used for this study in the Morphology Laboratory at the University of Pamplona. In a cadaver were findings: The main parotid duct originated two conducts: Left superior parotid duct and Left inferior parotid duct, is observed the criss-cross of the ducts, and then perforated the buccinator muscle and entered the oral cavity at a double parotid papilla containing a double opening, separated from each other in 0,98 mm. In the remaining  33 parotid regions (97.06% the parotid duct is conformed to the classical descriptions given in anatomical textbooks. Conclusions: The parotid duct anatomy is important for duct endoscopy, lithotripsy, sialography and trans-ductal facial nerve stimulation in the early stage of facial palsy in some cases. The anatomical variations also has clinical importance for parotid gland surgery and facial cosmetic surgery. To keep in mind the parotid duct variation will reduce iatrogenic injury risks and improve diagnosis of parotid duct injury.

  19. The Celiac Trunk and Its Anatomical Variations: A Cadaveric Study.

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    Pinal-Garcia, David F; Nuno-Guzman, Carlos M; Gonzalez-Gonzalez, Maria E; Ibarra-Hurtado, Tomas R

    2018-04-01

    The celiac artery, celiac axis or celiac trunk is the first major abdominal branch of the aorta. Anatomic variations and accessory vessels have been reported with variable percentages. The purpose of this study was to report the pattern of the celiac trunk and its anatomic variations in a sample of Mexican population. Celiac trunk dissection was performed in 140 fresh cadavers. Cadavers of Mexican subjects aged 18 years and older were included. Cadavers with previous upper abdominal surgery, abdominal trauma, disease process that distorted the arterial anatomy or signs of putrefaction were excluded. Celiac trunk variations and external diameter, accessory vessels, and vertebral level of origin were described. Celiac trunk patterns were reported according to the Panagouli classification. This study was reviewed and approved by the Ethics Committee of our Hospital. The celiac trunk derived in a common hepatic artery, a left gastric artery and a splenic artery (type I) in 43.6% of dissections. A true tripod was found in 7.1% and a false tripod in 36.4%. Celiac trunk bifurcation (type II) was found in 7.1%. Additional branches (type III) were observed in 47.9%. One or both phrenic arteries originated from the celiac trunk in 41.4% of dissections. Celiac trunk tetrafurcation was observed in 12.9%, pentafurcation in 12.9%, hexafurcation in 1.4%, and heptafurcation in 0.7%. The mean diameter of the celiac trunk ranged from 6 to 12 mm, with a mean diameter of 7.2 mm (SD = 1.39 mm). No significant difference was found between the diameters of the different types of celiac trunk (P > 0.05). The celiac trunk originated between the 12th thoracic and first lumbar vertebral bodies in 90% of dissections. Trifurcation of the celiac trunk was lower than previously reported. A high proportion of cases with additional vessels were found.

  20. Anatomic Variations of the Paranasal Sinuses on CT Scan Images

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    AR. Talaiepour

    2005-12-01

    Full Text Available Statement of Problem: Variation in paranasal sinus anatomy as shown on computed tomographic scans is of potential significance for it may pose risks during surgery or predispose to certain pathologic conditions.Purpose: The aim of this study was to assess the relative frequency and concurrence of variations in paranasal sinus anatomy in a given population and to compare the results with previous investigations conducted on different populations.Materials and Methods: All patients over 16 years of age referred to Valiasr hospital,Tehran, Iran, with paranasal sinus tomographic scans and a clinical diagnosis of chronic sinusitis were considered for this study. After excluding those with altered anatomy(iatrogenic or pathologic, scans of unaltered patients were meticulously analyzed for variations in sinus anatomy. Findings were recorded on the patient’s data sheet. The distance between the maxillary sinus floor and the alveolar ridge at the level of the 1stmolar was recorded. All findings were analyzed, and tested with Chi square, where applicable.Results: Overall 143 patients were analyzed (48.3% male and 51.7% female. The frequency of major sinus variations was: Agger nasi cell in 56.7%, Haller cell in 3.5%,Onodi cell in 7%, nasal septal deviation in 63%, Concha bullosa in 35%, and dental anomalies in 4.9% of the studied cases. The distance between the upper alveolar ridge and maxillary sinus floor was 0-30mm (mean 12.16 on the right, and 0-52mm (mean 12.20 on the left.Conclusion: The frequency of anatomic variations in sinus anatomy may be related to race and heredity. A lower number of cases in addition to the use of low yield imaging may explain the discrepancies observed between our results and other investigations.The findings of the present study were based on computed tomography.

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

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    Fritz Hans Schweingruber

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

  2. Anatomical variations of the torcular Herophili evaluated with MR venography

    International Nuclear Information System (INIS)

    Fukusumi, Akio; Tanaka, Takehiro; Koh, Sachiko; Nakagawa, Hiroyuki; Taoka, Toshiaki; Takayama, Katsutoshi; Sakamoto, Masahiko; Kichikawa, Kimihiko; Iwasaki, Satoru

    2002-01-01

    Anatomical variations of venous sinuses in the region of the torcular Herophili were evaluated with MR venography. We analyzed 200 MR venograms using Gd-DTPA enhanced 3D-field echo method with fat suppression with a 1.5 T unit. Compared with the size of the bilateral lateral sinuses (LS), the right LS were larger than the left LS by 68.5%. The left LS were larger than the right LS by 21.5%, same size by 10%. Partial aplasia or hypoplasia of the left LS were seen in 23 cases. The right sided aplasia were in two cases. Draining types of the superior sagittal sinus (SSS) and rectal sinus (RS) to the lateral sinus (LS) were classified into four. The SSS reached to the confluence and then joined to the bilateral LS (Sc type), 15%; SSS divided into two channels and then drained into each LS (S type), 26%; SSS drained into the right LS (Sr type), 49%; SSS drained into the left LS (Sl type), 10%. Similarly, the draining types of the RS were classified, Rc, R, Rr, Rl; 40.5%, 31%, 20%, 8.5%. Persistent occipital sinuses were recognized in 18%. An asymmetry of the LS mainly was due to the draining type of SSS at the confluence. The aplasia and/or hypoplasia of the LS and the configuration of the occipital sinuses could be analyzed precisely with MR venography. In conclusion, MR venography was proved reliable, non-invasive means for the evaluation of venous dural sinuses and provided useful informations for surgery. (author)

  3. 3 Variation in Leaf Anatomical Characters.cdr

    African Journals Online (AJOL)

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    Dry and wet season studies of the leaf anatomy of ten plant species in the family Euphorbiaceae from three sites with different pollution levels in Southwestern Nigeria were carried out. This is with a view to establish the response of plant anatomical structures to air pollution. The species investigated were Alchornea laxiflora.

  4. Anatomical variations of the circle of Willis and cerebrovascular accidents in transitional Albania

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    Edlira Harizi (Shemsi

    2015-12-01

    Full Text Available Aim: The purpose of this study was twofold: i in a case-control design, to determine the relationship between anatomical variations of the circle of Willis and cerebrovascular accidents; ii to assess the association between anatomical variations of the circle of Willis and aneurisms among patients with subarachnoid hemorrhage. Methods: A case-control study was conducted in Albania in 2013-2014, including 100 patients with subarachnoid hemorrhage and 100 controls (individuals without cerebrovascular accidents. Patients with subarachnoid hemorrhage underwent a CT angiography procedure, whereas individuals in the control group underwent a magnetic resonance angiography procedure. Binary logistic regression was used to assess the association between cerebrovascular accidents and the anatomical variations of the circle of Willis. Conversely, Fisher’s exact test was used to compare the prevalence of aneurisms between subarachnoid hemorrhage patients with and without anatomical variations of the circle of Willis. Results: Among patients, there were 22 (22% cases with anatomical variations of the circle of Willis compared with 10 (10% individuals in the control group (P=0.033. There was no evidence of a statistically significant difference in the types of the anatomical variations of the circle of Willis between patients and controls (P=0.402. In age- and-sex adjusted logistic regression models, there was evidence of a significant positive association between cerebrovascular accidents and the anatomical variations of the circle of Willis (OR=1.87, 95%CI=1.03-4.68, P=0.048. Within the patients’ group, of the 52 cases with aneurisms, there were 22 (42.3% individuals with anatomical variations of the circle of Willis compared with no individuals with anatomical variations among the 48 patients without aneurisms (P<0.001. Conclusion: This study provides useful evidence on the association between anatomical variations of the circle of Willis and

  5. Contribution to the anatomical nomenclature concerning general anatomy and anatomical variations.

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    Kachlik, David; Musil, Vladimir; Baca, Vaclav

    2016-09-01

    Nomenclature of the general and variant anatomy belongs to the most neglected parts of the Latin anatomical nomenclature in Terminologia Anatomica. Although many important small structures are included in Terminologia Anatomica, when describing and teaching particular anatomy of any part of the human body, the general terms are necessary, such as planes, lines and flexion grooves. Moreover, Terminologia Anatomica contains only 149 terms of variant structures, enlisted in the parentheses to differentiate them from constant ones. They are only a rather representative selection and some more should be added, both from the educational and clinical point of view. The authors present some terms, completed with their definitions or explanations concerning the general and variant anatomy to evoke broader discussion on this topic which should issue in incorporation of proposed terms (or their equivalents) into the Terminologia Anatomica.

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

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    Verenna, Anne-Marie

    2013-01-01

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

  7. Variations in Wood Anatomical Characteristics of Nigerian grown ...

    African Journals Online (AJOL)

    obeche) were investigated to assess the variation pattern of fibre, vessel and ray elements. Test samples were obtained axially from butt, 10%, 30%, 50%, 70% and 90% of merchantable height (MH); and radially from inner wood, middle wood and ...

  8. An anatomical variation of Superficial Palmar Arch and its clinical ...

    African Journals Online (AJOL)

    The familiarity of variations in vascular architecture of hand is helpful to surgeons, in microsurgical procedures precipitated by crush injuries of hand and in amputations. The efficiency of collateral circulation in hand is essential in certain peripheral vascular diseases like Raynaud's disease and in harvesting of the radial ...

  9. 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.

  10. Medial depression with bony dehiscence of lamina papyracea as an anatomic variation: CT evaluation

    International Nuclear Information System (INIS)

    Na, Sun Young; Lee, Young Uk; Youn, Eun Kyung; Suh, Sang Gyung; Kim, Dong Hyun

    1994-01-01

    To evaluate the incidence and CT findings of the medial depression and bony dehiscence of lamina papyracea as an anatomic variation. 1472 PNS CTs of the patients with symptoms of chronic sinusitis were retrospectively evaluated. The total incidence of depressed lamina papyracea as an anatomic variation was 3.5%(52/1472) on PNS CT. There was a statistically significant correlation between the increasing age and the incidence of depressed lamina papyracea. Depression of lamina papyracea anterior to the basal lamella were more common than those of the posterior depression. Associated findings were herniation of adjacent fatty tissue in all cases and the medial bowing and hypertrophied configuration of the medial rectus muscle without significant herniation in 19 cases(34%). Nontraumatic, asymptomatic depression with bony dehiscence of lamina papyracea as an anatomic variation is not uncommon with the incidence of 3.5%. Recognition of its existence and degree may be helpful in avoiding various ocular complication during ethmoid surgery

  11. Remarkable anatomic variations in paranasal sinus region and their clinical importance

    Energy Technology Data Exchange (ETDEWEB)

    Kantarci, Mecit E-mail: akkanrad@hotmail.com; Karasen, R. Murat; Alper, Fatih; Onbas, Omer; Okur, Adnan; Karaman, Adem

    2004-06-01

    With the advent of functional endoscopic sinus surgery (FESS) and coronal computed tomography (CT) imaging, considerable attention has been directed toward paranasal region anatomy. Detailed knowledge of anatomic variations in paranasal sinus region is critical for surgeons performing endoscopic sinus surgery as well as for the radiologist involved in the preoperative work-up. To be in the known anatomical variants with some accompanying pathologies, directly influence the success of diagnostic and therapeutic management of paranasal sinus diseases. A review of 512 (1024 sides) paranasal sinus tomographic scans was carried out to expose remarkable anatomic variations of this region. We used only coronal sections, but for some cases to clear exact diagnosis, additional axial CT scan, magnetic resonance imaging (MRI) and nasal endoscopy were also performed. In this pictorial essay, rates of remarkable anatomic variations in paranasal region were displayed. The images of some interesting cases were illustrated, such as the Onodi cell in which isolated mucocele caused loss of visual acuity, agger nasi cell, Haller's cell, uncinate bulla, giant superior concha bullosa, inferior concha bullosa, bilateral carotid artery protrusion into sphenoid sinus, maxillary sinus agenesis, bilateral secondary middle turbinate (SMT) and sphenomaxillary plate. The clinical importance of all these variations were discussed under the light of the literature. It was suggested that remarkable anatomic variations of paranasal region and their possible pathologic consequences should be well defined in order to improve success of management strategies, and to avoid potential complications of endoscopic sinus surgery. The radiologist must pay close attention to anatomical variations in the preoperative evaluation.

  12. The 4D hyperspherical diffusion wavelet: A new method for the detection of localized anatomical variation.

    Science.gov (United States)

    Hosseinbor, Ameer Pasha; Kim, Won Hwa; Adluru, Nagesh; Acharya, Amit; Vorperian, Houri K; Chung, Moo K

    2014-01-01

    Recently, the HyperSPHARM algorithm was proposed to parameterize multiple disjoint objects in a holistic manner using the 4D hyperspherical harmonics. The HyperSPHARM coefficients are global; they cannot be used to directly infer localized variations in signal. In this paper, we present a unified wavelet framework that links Hyper-SPHARM to the diffusion wavelet transform. Specifically, we will show that the HyperSPHARM basis forms a subset of a wavelet-based multiscale representation of surface-based signals. This wavelet, termed the hyperspherical diffusion wavelet, is a consequence of the equivalence of isotropic heat diffusion smoothing and the diffusion wavelet transform on the hypersphere. Our framework allows for the statistical inference of highly localized anatomical changes, which we demonstrate in the first-ever developmental study on the hyoid bone investigating gender and age effects. We also show that the hyperspherical wavelet successfully picks up group-wise differences that are barely detectable using SPHARM.

  13. Anatomical Variations of Brachial Artery - Its Morphology, Embryogenesis and Clinical Implications

    Science.gov (United States)

    KS, Siddaraju; Venumadhav, Nelluri; Sharma, Ashish; Kumar, Neeraj

    2014-01-01

    Background: Accurate knowledge of variation pattern of the major arteries of upper limb is of considerable practical importance in the conduct of reparative surgery in the arm, forearm and hand however brachial artery and its terminal branches variations are less common. Aim: Accordingly the present study was designed to evaluate the anatomical variations of the brachial artery and its morphology, embryogenesis and clinical implications. Materials and Methods: In an anatomical study 140 upper limb specimens of 70 cadavers (35 males and 35 females) were used and anatomical variations of the brachial artery have been documented. Results: Accessory brachial artery was noted in eight female cadavers (11.43%). Out of eight cadavers in three cadavers (4.29%) an unusual bilateral accessory brachial artery arising from the axillary artery and it is continuing in the forearm as superficial accessory ulnar artery was noted. Rare unusual variant unilateral accessory brachial artery and its reunion with the main brachial artery in the cubital fossa and its variable course in relation to the musculocutaneous nerve and median nerve were also noted in five cadavers (7.14%). Conclusion: As per our knowledge such anatomical variations of brachial artery and its terminal branches with their relation to the surrounding structures are not reported in the modern medical literature. An awareness of such a presence is valuable for the surgeons and radiologists in evaluation of angiographic images, vascular and re-constructive surgery or appropriate treatment for compressive neuropathies. PMID:25653931

  14. Computerized Tomographic Study on the Anatomic Variation of the Paranasal Sinus

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Sun Kyung; Lim, Sug Young; Koh, Kwang Joon [Dept. of Oral and Maxillofacial Radiology and Institute of Oral Bio Science, College of Dentistry, Chonbuk National University, Chonju (Korea, Republic of); Park, Mi Ju [Dept. of Prosthodontics, School of Denstistry, Chonbuk National Universty, Chonju (Korea, Republic of)

    1999-08-15

    To evaluate the anatomic variations of the paranasal sinuses on computed tomographs. The author examined the CT images of the paranasal sinuses retrospectively in 500 patients who visited Chonbuk National University Hospital between January 1996 and December 1997. The highest incidence of anatomic variation of the paranasal sinuses in bilateral structures was agger nasi cell (73.2%), followed by concha bullosa (31.1%), Onodi cell (24.0%), Haller cell (19.8%), maxillary sinus septum (13.0%), paradoxical middle turbinate (2.5%), pneumatized uncinate process (2.0%), and bent uncinate process. The highest incidence of anatomic variation in midline structures was nasal septum deviation(53.2%), followed by nasal septumaerated (29.4%), bulla galli (24.7%) asymmetric intersphenoid septum (22.3%), and nasal septum spur (13.8%). The correlation between anatomic variation and paranasal sinusitis was not found. The results of this study will aid in the diagnosis and treatment of paranasal sinus diseases, especially in the treatment planning before functional endoscopic surgery.

  15. Anatomical basics, variations, and degenerative changes of the shoulder joint and shoulder girdle

    Energy Technology Data Exchange (ETDEWEB)

    Prescher, Andreas E-mail: dkeyserlingk@post.klinikum.rwth-aachen.de

    2000-08-01

    This paper summarizes the anatomical basics of the shoulder, their variations, and precise definitions, including differential diagnoses. It also describes the characteristic degenerative changes caused by aging. A typical variation (7-15%) is the os acromiale, which forms the triangular epiphysis of the scapular spine. This abnormality must be differentiated from a fracture of the acromion or a pseudarthrosis. Because ossification of the acromion is complete after age 25, the os acromiale should be diagnosed only after this age. The shape of the acromion is a further important feature. In a recent anatomical study, the following frequencies of the Bigliani-types of the acromial shape were anatomically determined - type 1 (flat), 10.2% and type 2 (curved), 89.8%. Type 3 (hooked) was not observed, which indicates that this type is probably a misinterpretation of the so-called acromial spur. Minor dehiscences and perforations in the infraspinate or supraspinate fossa should not be confused with malignant osteolyses. The scapula has three ligaments of its own, (1) the coracoacromial ligament and its osseous fixations form an osteofibrous arch above the shoulder joint, which plays a part in impingement syndrome; (2) the superior transverse scapular ligament or its ossified correlate arches the scapular incisure and can cause a typical compression syndrome of the suprascapular nerve; (3) the inferior transverse scapular ligament is of no great clinical importance. Two intraarticular structures (glenoid labrum and tendon of the long bicipital head) must be mentioned. The glenoid labrum consists of dense connective tissue and surrounds the margin of the glenoid cavity. Two areas exhibit specialized conditions, cranial at the supraglenoid tubercle an intimate relationship exists to the tendon of the long bicipital head and in about 55% of cases, the labrum is stretched over the glenoid rim at the ventral side. At the area of the biceps-tendon-labrum complex, so-called SLAP

  16. Anatomical basics, variations, and degenerative changes of the shoulder joint and shoulder girdle

    International Nuclear Information System (INIS)

    Prescher, Andreas

    2000-01-01

    This paper summarizes the anatomical basics of the shoulder, their variations, and precise definitions, including differential diagnoses. It also describes the characteristic degenerative changes caused by aging. A typical variation (7-15%) is the os acromiale, which forms the triangular epiphysis of the scapular spine. This abnormality must be differentiated from a fracture of the acromion or a pseudarthrosis. Because ossification of the acromion is complete after age 25, the os acromiale should be diagnosed only after this age. The shape of the acromion is a further important feature. In a recent anatomical study, the following frequencies of the Bigliani-types of the acromial shape were anatomically determined - type 1 (flat), 10.2% and type 2 (curved), 89.8%. Type 3 (hooked) was not observed, which indicates that this type is probably a misinterpretation of the so-called acromial spur. Minor dehiscences and perforations in the infraspinate or supraspinate fossa should not be confused with malignant osteolyses. The scapula has three ligaments of its own, (1) the coracoacromial ligament and its osseous fixations form an osteofibrous arch above the shoulder joint, which plays a part in impingement syndrome; (2) the superior transverse scapular ligament or its ossified correlate arches the scapular incisure and can cause a typical compression syndrome of the suprascapular nerve; (3) the inferior transverse scapular ligament is of no great clinical importance. Two intraarticular structures (glenoid labrum and tendon of the long bicipital head) must be mentioned. The glenoid labrum consists of dense connective tissue and surrounds the margin of the glenoid cavity. Two areas exhibit specialized conditions, cranial at the supraglenoid tubercle an intimate relationship exists to the tendon of the long bicipital head and in about 55% of cases, the labrum is stretched over the glenoid rim at the ventral side. At the area of the biceps-tendon-labrum complex, so-called SLAP

  17. Anatomical variations of rami communicantes in the upper thoracic sympathetic trunk.

    Science.gov (United States)

    Cho, Hyun Min; Lee, Doo Yun; Sung, Sook Whan

    2005-02-01

    .81/9.40 mm among 26 cadavers. The mean distance of each side was 6.81/7.94 mm at the level of the third intercostal nerve. And at the level of the fourth intercostal nerve, the mean distance was 7.48/10.92 mm, respectively. On the basis of this study, the anatomical variations of communicating rami could explain some surgical failures and recurrences. Moreover, in addition to the conventional surgical methods (sympathectomy, sympathicotomy, clipping of sympathetic chain and ramicotomy), dividing the inconstant sympathetic pathways (nerve of Kuntz, ascending or descending rami communicantes) on the second, the third and the fourth ribs will help to get better surgical effect.

  18. Comparative analysis of mandibular anatomical variations between panoramic radiography and cone beam computed tomography.

    Science.gov (United States)

    Neves, Frederico Sampaio; Nascimento, Monikelly Carmo Chagas; Oliveira, Matheus Lima; Almeida, Solange Maria; Bóscolo, Frab Norberto

    2014-12-01

    The objective of this study is to compare the ability of panoramic radiography and cone beam computed tomography (CBCT) in detecting anatomical variations of the mandibular canal and mental foramen. One hundred twenty-seven preoperative panoramic and CBCT images were evaluated. Two oral and maxillofacial radiologists investigated the presence of bifid mandibular canals and/or additional mental foramina on the right, left, or both sides of the mandible. Intra- and interobserver reliability was determined using Cohen's kappa coefficient. McNemar's test compared the prevalence of mandibular anatomical variations between panoramic radiography and CBCT. The significance level was set at 0.05. Additional mental foramen and bifid mandibular canal were detected in 1.2 and 7.4 % of the panoramic radiographs and 7.4 and 9.8 % of the CBCT images, respectively. The incidence of anatomical variations on the mandibular canal was not significantly different between both imaging modalities (P > 0.05). Although CBCT provides better viewing of anatomical structures, including location, shape, and relationship with the surrounding area, panoramic radiography is a conventional imaging modality that can be used in the study of the bifid mandibular canals.

  19. Anatomic Variation of the Median Nerve Associated with an Anomalous Muscle of the Forearm.

    Science.gov (United States)

    Atoni, Atoni Dogood; Oyinbo, Charles Aidemise

    2017-03-01

    Documented anatomical variations are important not only for the study of the subject of anatomy, but also in clinical situation. This knowledge would aid surgeons in planning a preoperative strategy for surgical procedures and reconstructive surgery. The right forearm of a 35-year-old embalmed male cadaver present a splitting of the median nerve in the proximal 1/3 of the forearm to form medial and lateral divisions that accommodate an anomalous muscle. The split median nerve reunites at the distal 1/3 and continues as a single nerve. The anomalous muscle arises by muscle fibers from flexor digitorum superficialis and inserted by tendon into flexor digitorum profundus. There was no such variation in the left forearm. The knowledge of such anatomical variations is important to clinicians and surgeons in interpreting atypical clinical presentations and avoiding unusual injury during surgery.

  20. Anatomic Variation of the Median Nerve Associated with an Anomalous Muscle of the Forearm

    Directory of Open Access Journals (Sweden)

    Atoni Atoni Dogood

    2017-03-01

    Full Text Available Documented anatomical variations are important not only for the study of the subject of anatomy, but also in clinical situation. This knowledge would aid surgeons in planning a preoperative strategy for surgical procedures and reconstructive surgery. The right forearm of a 35-year-old embalmed male cadaver present a splitting of the median nerve in the proximal 1/3 of the forearm to form medial and lateral divisions that accommodate an anomalous muscle. The split median nerve reunites at the distal 1/3 and continues as a single nerve. The anomalous muscle arises by muscle fibers from flexor digitorum superficialis and inserted by tendon into flexor digitorum profundus. There was no such variation in the left forearm. The knowledge of such anatomical variations is important to clinicians and surgeons in interpreting atypical clinical presentations and avoiding unusual injury during surgery.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    International Nuclear Information System (INIS)

    Torres, Marianna Guanaes Gomes; De Faro Valverde, Ludmila; Vidal, Manuela Torres Andion; Crusoe-Rebello, Ieda Margarida

    2015-01-01

    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.

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

    Science.gov (United States)

    Torres, Marianna Guanaes Gomes; Valverde, Ludmila de Faro; Vidal, Manuela Torres Andion; Crusoé-Rebello, Iêda Margarida

    2015-03-01

    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.

  4. HPV Vaccine Effective at Multiple Anatomic Sites

    Science.gov (United States)

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

  5. Anatomic variations of the branches of the aortic arch in a Peruvian population.

    Science.gov (United States)

    Huapaya, Julio Arturo; Chávez-Trujillo, Kristhy; Trelles, Miguel; Dueñas Carbajal, Roy; Ferrandiz Espadin, Renato

    2015-07-31

    Previous publications from two countries in South America found one anatomical variation not previously reported in the rest of the world, which in turn give some clues with regard to a racial difference. The objective of the present study is to describe variations in the anatomical distribution of the branches of the aortic arch in a Peruvian population. To describe variations in the anatomical distribution of the branches of the aortic arch in a Peruvian population. A descriptive study of patients who underwent a tomography angiography of the aorta was performed. We analyzed the reports that showed the description of the variations of the branches of the aortic arch based on the eight types currently described in the literature. From 361 analyzed reports, 282 patients (78.12%) had a normal aortic arch configuration (type I; aortic arch gives rise to the brachiocephalic trunk, left common carotid and left subclavian arteries); followed by type II (left common carotid artery as a branch of the aorta) with 41 patients (11.36%); and type IX (common ostium for the brachiocephalic trunk and the left common carotid artery) with 25 patients (6.93%). The latter and two other types are new variations. Aortic Arch Type I, Type II and Type IX were the most frequent variations in this Peruvian study. Additionally, we also found two more new types that have not been previously described in the literature. Further investigation regarding these variations is needed in order to assess a racial factor in South America and possible relationships with clinical or surgical events.

  6. Interfractional Variations in Patient Setup and Anatomic Change Assessed by Daily Computed Tomography

    International Nuclear Information System (INIS)

    Li, X. Allen; Qi, X. Sharon; Pitterle, Marissa; Kalakota, Kapila; Mueller, Kevin; Erickson, Beth A.; Wang Dian; Schultz, Christopher J.; Firat, Selim Y.; Wilson, J. Frank

    2007-01-01

    Purpose: To analyze the interfractional variations in patient setup and anatomic changes at seven anatomic sites observed in image-guided radiotherapy. Methods and Materials: A total of 152 patients treated at seven anatomic sites using a Hi-Art helical tomotherapy system were analyzed. Daily tomotherapy megavoltage computed tomography images acquired before each treatment were fused to the planning kilovoltage computed tomography images to determine the daily setup errors and organ motions and deformations. The setup errors were corrected before treatment and were used, along with the organ motions, to determine the clinical target volume/planning target volume margins. The organ motions and deformations for 3 representative patient cases (pancreas, uterus, and soft-tissue sarcoma) and for 14 kidneys of 7 patients are presented. Results: Interfractional setup errors in the skull, brain, and head and neck are significantly smaller than those in the chest, abdomen, pelvis, and extremities. These site-specific relationships are statistically significant. The margins required to account for these setup errors range from 3 to 8 mm for the seven sites. The margin to account for both setup errors and organ motions for kidney is 16 mm. Substantial interfractional anatomic changes were observed. For example, the pancreas moved up to ±20 mm and volumes of the uterus and sarcoma varied ≤30% and 100%, respectively. Conclusion: The interfractional variations in patient setup and in shapes, sizes, and positions of both targets and normal structures are site specific and may be used to determine the site-specific margins. The data presented in this work dealing with seven anatomic sites may be useful in developing adaptive radiotherapy

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-05-15

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

  8. Anatomical variations of mandibular canal detected by panoramic radiography and CT: a systematic review and meta-analysis.

    Science.gov (United States)

    Haas, Letícia F; Dutra, Kamile; Porporatti, André Luís; Mezzomo, Luis A; De Luca Canto, Graziela; Flores-Mir, Carlos; Corrêa, Márcio

    2016-01-01

    To investigate the anatomical variations of the mandibular canal through assessment in situ, panoramic radiography, CT or CBCT and assess their frequency. Articles were selected from databases (Cochrane Library, LILACS, ProQuest, PubMed, Scopus, Web of Science and Google Scholar), articles without limitations of language, in which the main objective was to evaluate the frequency of bifurcation of the mandibular canal through assessment in situ, panoramic radiography, CT or CBCT were selected. A meta-analysis of prevalence using random effects was performed. Using a selection process in two phases, 15 articles were identified, and a meta-analysis was conducted. The results from these meta-analyses showed that the overall prevalence of anatomical variations for in situ studies was 6.46%, and through assessment of panoramic radiography and CT or CBCT the overall prevalence shown was 4.20% and 16.25%, respectively. There are two types of variations of the mandibular canal: the retromolar canal and bifid mandibular canal. The frequency variations through assessing in situ, panoramic radiography and CT or CBCT were 6.46%, 4.20% and 16.25%, respectively.

  9. Anatomical variations of the thymus in relation to the left brachiocephalic vein, findings of necropsia.

    Science.gov (United States)

    Plaza, Oscar Alonso; Moreno, Freddy

    2018-04-01

    Two cases of anatomical variations of the thymus are presented with respect to the anatomical relations with the left brachiocephalic vein and found during the necropsy process. Less than 2 days after birth with Noonan Syndrome, when the left brachiocephalic vein was scanning behind the upper thymus horns, there were other adjacent lesions consisting of three supernumerary spleens and three hepatic veins. The second case was an 8-year-old infant with child malpractice who died from urinary sepsis due to obstructive uropathy, in which case the upper lobes of the thymus were fused and formed a ring through which the left brachiocephalic vein passed. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. Dosimetric effects of anatomical changes during fractionated photon radiation therapy in pancreatic cancer patients

    NARCIS (Netherlands)

    van der Horst, Astrid; Houweling, Antonetta C.; van Tienhoven, Geertjan; Visser, Jorrit; Bel, Arjan

    2017-01-01

    Pancreatic tumors show large interfractional position variation. In addition, changes in gastrointestinal gas volumes and body contour take place over the course of radiation therapy. We aimed to quantify the effect of these anatomical changes on target dose coverage, for the clinically used

  11. [Anatomic variations of the hepatic artery : a study of 33 cases and review].

    Science.gov (United States)

    Daghfous, Amine; Baraket, Oussama; Bedioui, Heykal; Ayadi, Sofiene; Mighri, Mongi; Touinsi, Hassen; Jouini, Mohamed; Kacem, Montacer; Ben Safta, Zoubeir; Sadok, Sassi

    2011-05-01

    The hepatic artery is prone to numerous anatomic variations dictated by certain variables of the organogenesis. Aim : To research study the anatomic variations of the hepatic artery as well as their implications within surgical practice. Study of a post-mortem series of 33 cases of dissection of the hepatic pedicle with fresh corpses (deaths amounting no longer than 24 hours), carried out in conditions that are quite close to those met with the living ones. The common hepatic artery was divided at the foot of the hepatic pedicle into a gastro duodenal artery and into a proper hepatic artery in 94% of the cases. In 6% of the cases, we noticed a three level change, a branching of the average hepatic artery into a gastro duodenal artery, a right hepatic artery and a left hepatic artery. The proper hepatic artery represented the pedicle segment of the hepatic artery in 94% of the cases. In 36% of the cases, the liver was irrigated by two hepatic arteries. In 12% of the cases, there was the matter of the right hepatic artery, branch of the mesenteric artery. In 24% of the cases, there was the matter of the left hepatic artery branch of the left gastric artery. The perfect knowledge in preoperative and preoperative stages of the anatomic variations of the hepatic pedicle is quite essential. Actually, the lack of knowledge of these variations exposes to the risk of certain complications which are sometimes deadly during hepatic transplants, pancreatic surgery, cholecystectomies, through laroscopic way as well as in the treatment of gastro-esophagus surging.

  12. Anatomic and energy variation of scatter compensation for digital chest radiography with Fourier deconvolution

    International Nuclear Information System (INIS)

    Floyd, C.E.; Beatty, P.T.; Ravin, C.E.

    1988-01-01

    The Fourier deconvolution algorithm for scatter compensation in digital chest radiography has been evaluated in four anatomically different regions at three energies. A shift invariant scatter distribution shape, optimized for the lung region at 140 kVp, was applied at 90 kVp and 120 kVp in the lung, retrocardiac, subdiaphragmatic, and thoracic spine regions. Scatter estimates from the deconvolution were compared with measured values. While some regional variation is apparent, the use of a shift invariant scatter distribution shape (optimized for a given energy) produces reasonable scatter compensation in the chest. A different set of deconvolution parameters were required at the different energies

  13. Technical note: Quantification of neurocranial shape variation using the shortest paths connecting pairs of anatomical landmarks.

    Science.gov (United States)

    Morita, Yusuke; Ogihara, Naomichi; Kanai, Takashi; Suzuki, Hiromasa

    2013-08-01

    Three-dimensional geometric morphometric techniques have been widely used in quantitative comparisons of craniofacial morphology in humans and nonhuman primates. However, few anatomical landmarks can actually be defined on the neurocranium. In this study, an alternative method is proposed for defining semi-landmarks on neurocranial surfaces for use in detailed analysis of cranial shape. Specifically, midsagittal, nuchal, and temporal lines were approximated using Bezier curves and equally spaced points along each of the curves were defined as semi-landmarks. The shortest paths connecting pairs of anatomical landmarks as well as semi-landmarks were then calculated in order to represent the surface morphology between landmarks using equally spaced points along the paths. To evaluate the efficacy of this method, the previously outlined technique was used in morphological analysis of sexual dimorphism in modern Japanese crania. The study sample comprised 22 specimens that were used to generate 110 anatomical semi-landmarks, which were used in geometric morphometric analysis. Although variations due to sexual dimorphism in human crania are very small, differences could be identified using the proposed landmark placement, which demonstrated the efficacy of the proposed method. Copyright © 2013 Wiley Periodicals, Inc.

  14. 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

    2017-09-01

    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).

  15. Preserving and sharing examples of anatomical variation and developmental anomalies via photorealistic virtual reality.

    Science.gov (United States)

    Nieder, Gary L; Nagy, Frank; Wagner, Lynn A

    2004-01-01

    Computer graphics technology has made it possible to create photographic-quality virtual specimens from real anatomical material. One technique for doing this, QuickTime Virtual Reality (QTVR), results in virtual specimens that are easily shared on the Internet and displayed as standalone entities or incorporated into complex programs or Web sites. A compelling use of this technology is the sharing of rare specimens such as unusual variations, developmental anomalies or gross pathology. These types of specimens have traditionally been confined to anatomical museums, but could serve a much more useful existence as freely shared virtual specimens. An example presented here is a relatively rare developmental defect in the embryonic aortic arches that results in a right-sided aortic arch coursing posterior to the trachea and esophagus. In a time of ever increasing restraints on the practical side of anatomy education, an Internet-based library of human variation and other rare specimens would be a useful supplement to students' limited exposure to the human body. Since the discovery and preparation of specimens would be the rate-limiting step in producing such a collection, we propose the establishment of a center for virtual specimen creation and preservation through a cooperative effort by gross anatomists and pathologists in contributing the source material. This collection, a work in progress, is available at www.anatomy.wright.edu/qtvr. Copyright 2004 Wiley-Liss, Inc.

  16. ANATOMICAL VARIATIONS OF THE GASTROCNEMIUS MUSCLE- A DISSECTION-BASED STUDY

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    Rajat Dutta Roy

    2017-11-01

    Full Text Available BACKGROUND In human, the bulk of the posterior compartment of the leg is formed by the gastrocnemius and the soleus muscle. The superficially-placed gastrocnemius is a bipennate muscle, but according to available literature, it exhibits numerous anatomical variations. The aim of the present study is to find out the anatomical variations of the gastrocnemius muscle in this part of Assam. MATERIALS AND METHODS The present study undertaken in the Department of Anatomy, Jorhat Medical College, from August 2014 to August 2017 included 30 lower limbs from 15 embalmed cadavers of known sexes. These cadavers were provided to the first year MBBS students for routine dissection procedure. After carrying out the dissection as per Cunningham’s Manual of Practical Anatomy, the gastrocnemius muscle was examined for its two heads of origin. Any accessory heads found were noted and recorded. RESULTS Out of the 30 lower limb specimens, 28 (93.33% limbs presented with the normal two-headed gastrocnemius muscle, while 2 (6.66% limbs (1 right and 1 left, presented with four-headed gastrocnemius muscle. Both these limbs belonged to male cadavers. CONCLUSION The precise knowledge of occurrence of multi-headed gastrocnemius muscle should be kept in mind, while performing myocutaneous flaps around the knee joint and also during limb salvage procedures or limb sparing surgery.

  17. Variations in the anatomic relations of the posterior interosseous nerve associated with proximal forearm trauma.

    Science.gov (United States)

    Calfee, Ryan P; Wilson, Joyce M; Wong, Ambrose H W

    2011-01-05

    The posterior interosseous nerve is at risk for iatrogenic injury during surgery involving the proximal aspect of the radius. Anatomic relationships of this nerve in skeletally intact cadavers have been defined, but variations associated with osseous and soft-tissue trauma have not been examined. This study quantifies the effect of a simulated diaphyseal fracture of the proximal aspect of the radius and of a radial neck fracture with an Essex-Lopresti injury on the posterior interosseous nerve. In twenty unembalmed cadaveric upper extremities, the distance from the radiocapitellar joint to the point where the posterior interosseous nerve crosses the midpoint of the axis of the radius (Thompson approach) was recorded in three forearm positions (supination, neutral, and pronation). Specimens were then treated with either proximal diaphyseal osteotomy (n = 10) or radial head excision with simulated Essex-Lopresti injury (n = 10), and the position of the nerve in each forearm position was remeasured. We evaluated the effect of the simulated trauma on nerve position and correlated baseline measurements with radial length. In neutral rotation, the posterior interosseous nerve crossed the radius at a mean of 4.2 cm (range, 2.5 to 6.2 cm) distal to the radiocapitellar joint. In pronation, the distance increased to 5.6 cm (range, 3.1 to 7.4 cm) (p 0.50, p = 0.01). Diaphyseal osteotomy of the radius markedly decreased the effect of forearm rotation, as the change in nerve position from supination to pronation decreased from 2.13 ± 0.8 cm to 0.24 ± 0.2 cm (p = 0.001). Proximal migration of the radius following radial head excision was accompanied by similar magnitudes of proximal nerve migration in all forearm positions. Forearm pronation has minimal effect on posterior interosseous nerve position within the surgical window following a displaced diaphyseal osteotomy of the proximal aspect of the radius. The nerve migrates proximally toward the capitellum with proximal

  18. The effects of selected anatomical characteristics on physical ...

    African Journals Online (AJOL)

    The effects of selected anatomical characteristics on physical properties of Ethiopian Highland Bamboo Arundinaria Alpina K. Schum. (Poaceae) ... In early maturing bamboo, fibers are relatively small in wall thickness. The results of statistical analyses revealed that bamboo portion has significant effects on all variables.

  19. 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.

  20. An eccentric anatomical variation of palmar vascular pattern: Report of surgical challenging vascular variation

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    Jyothsna Patil

    2016-01-01

    Full Text Available The knowledge of variations in the vascular architecture of hand is of great importance to surgeons, orthopedicians, and plastic surgeons in microsurgical procedures following crush injuries of the hand and amputations. The efficiency of collateral circulation in hand is essential in few peripheral vascular diseases like Raynaud′s disease and harvesting of the radial artery for the coronary bypass graft. During routine dissection of the right upper limb of a 55-year-old male cadaver, we observed that the superficial palmar arch (SPA is formed by the ulnar artery and completed by the first dorsal metacarpal artery. After completing the arch, dorsal metacarpal artery continued as princeps pollicis artery for the thumb. The common palmar digital artery supplying the contiguous side of index and middle fingers passed through the neural loop formed by the proper digital nerve supplying the radial side of the middle finger and joined with the unusually large first palmar metacarpal artery before dividing into proper digital arteries. The first palmar metacarpal artery also gave origin to radialis indicis artery which in turn ran deep to tendons of the index finger to reach index finger. The common palmar digital artery supplying the contiguous side of middle and ring fingers also passed through the neural loop formed by the proper digital nerve supplying the ulnar side of the middle finger. The deep palmar branch of ulnar artery gave proper digital artery to little finger.

  1. 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

  2. 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.

  3. Anatomic Variation of Rami Communicantes in the Upper Thoracic Sympathetic Chain: A Human Cadaveric Study.

    Science.gov (United States)

    Street, Elliot; Ashrafi, Mohammed; Greaves, Nicholas; Gouldsborough, Ingrid; Baguneid, Mohamed

    2016-07-01

    Hyperhidrosis is secondary to over activation of the sympathetic nervous system and surgical sympathectomy is the treatment of choice when other modalities have failed. This study investigated anatomic variation in the upper thoracic sympathetic chain and associated rami communicantes among cadaveric specimens. It considers the implications of these findings on surgical techniques to treat hyperhidrosis. The upper 4 thoracic sympathetic ganglia, intercostal nerves, and connecting rami were dissected, measured and mapped in 40 sides of 20 adult human cadavers. Ganglia location was recorded. The incidence, orientation, and distance travelled by rami communicantes was compared across different ganglionic levels and between sides. The percentage of ganglia located below their associated intercostal space was 6.25% with stellate ganglions present in 70% of specimens and Kuntz fibers noted in 40%. There was a stepwise reduction in incidence of rami from superior to inferior placed ganglia. The number of rami identified across all levels was significantly greater on the right (P = 0.03). The horizontal distance between the sympathetic chain and union of the rami on the intercostal nerves was significantly greater on the right across all levels (P = 0.04). There was substantial variation in the rami communicantes across the upper 4 ganglia and between right and left sides. Consideration of this variation should be given when planning surgical sympathectomy for hyperhidrosis particularly to avoid symptom recurrence. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. 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.

  5. Anatomical Variations of the Blood Vascular System in Veterinary Medicine. The Internal Iliac Artery of the Dog. Part Two.

    Science.gov (United States)

    Avedillo, L; Martín-Alguacil, N; Salazar, I

    2016-04-01

    The aim of this study was to investigate the variability of the internal pudendal artery. Two hundred and thirty-two pelvic halves from 116 adult dogs were examined. Twenty-six anatomical variations were found, thirteen occurring in more than 5% of the dogs. Anatomical variations were grouped in relation to the origin of the prostatic/vaginal arteries, middle rectal artery, urethral artery, ventral perineal and caudal rectal arteries. The chi-squared test was used to analyse differences in sex, side of the body, profile and size, and the results were considered statistically significant when P ≤ 0.05. An identical vascular pattern in both hemipelvises was found for most of the anatomical variations described. © 2015 Blackwell Verlag GmbH.

  6. Trifid nasopalatine canal: case report of a rare anatomical variation and its surgical implications

    International Nuclear Information System (INIS)

    Guanaes Gomes Torres, Marianna; Crusoé-Rebello, Margarida Iêda; Faro Valverde, Ludmila de; Torres Andion Vidal, Manuela

    2016-01-01

    The nasopalatine canal is a long slender structure present in the midline of the anterior maxilla that connects the palate to the floor of the nasal cavity. The nasopalatine canal contains the nasopalatine nerve, the terminal branch of the nasopalatine artery, fibrous connective tissue, adipose tissue, and minor salivary glands. The purpose of this article was to report a case of a trifid nasopalatine canal detected by cone beam computed tomography prior to dental implant placement. A 47-year-old female patient was submitted to cone beam computed tomography. Axial and sagittal sections revealed a trifurcation of the nasopalatine canal. Each canal was separated from the other by bony septa and extended independently from the floor of the nasal cavity to the incisive foramen in the remnant of the alveolar process in the anterior region of the maxilla. Cone beam computed tomography has permitted better visualization of the details and anatomical variations of the nasopalatine canal. Detailed knowledge of variations in the shape, number and size of the nasopalatine canal is fundamental for surgical procedures, such as local anesthesia in the anterior maxillary region and placement of dental implants, in order to prevent damage to important arteries and nerves. (author)

  7. Variations in the anatomical positioning of impacted mandibular wisdom teeth and their practical implications.

    Science.gov (United States)

    Schneider, Thomas; Filo, Katharina; Kruse, Astrid L; Locher, Michael; Grätz, Klaus W; Lübbers, Heinz-Theo

    2014-01-01

    Surgical removal of impacted third molars is one of the most frequent procedures in oral surgery. Here, three-dimensional (3D) imaging is often used, yet its necessity is still being heavily debated. The aim of the study was to describe the variation in the anatomical positioning of third mandibular molars, and, by doing so, examine the necessity of 3D imaging. A retrospective case study was performed with the patients from an oral surgery department from January 2009 to February 2013. The primary focus of the study was on the spatial relationship to the mandibular canal, as well as angulation, root configuration, and developmental stage of the wisdom tooth. Descriptive statistics were calculated for these variables. A total of 1197 wisdom teeth in 699 patients were evaluated. 46.7% exhibited direct contact to the mandibular canal, another 28.7% showed close proximity and 24.6% a measurable distance. In 29.0%, the mandibular canal was vestibular and in 23.8% lingual to the wisdom tooth. In 7.4%, it was interradicular and in 0.6% intraradicular. Most teeth had one (21.3%) or two (55.3%) roots. Others had three (17.6%), four (2.0%) or five (0.2%) roots. In 31.4% of the teeth, the root perforated the lingual compact bone, and in 4.3% the vestibular compact bone. 44.4% of the teeth had mesial angulation, 9.7% distal angulation, 35.3% lingual and 2.9% buccal angulation. Due to the anatomical variety, the use of 3D imaging is recommended before surgical removal of mandibular third molars if conventional imaging cannot exclude complicated conditions.

  8. Lingual Foramina and Canals of the Mandible: Anatomic Variations in a Lebanese Population

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    Georges Aoun

    2017-01-01

    Full Text Available Objective: The aim of this study was to evaluate the mandibular lingual foramina (LF and canals and their anatomic variations using cone-beam computed tomography (CBCT technology in a Lebanese population. Materials and Methods: In this study, we analyzed CBCT images of 90 adult Lebanese patients (41 males and 49 females. We assessed the number and location of the LF. In additional, we measured: (a The distance from both the alveolar crest and the inferior border of the mandible to the LF and (b the length of the lingual canals (LCs. The data obtained was analyzed statistically using Shapiro–Wilk normality test, t-test, Chi-square, and Fisher's exact tests. Statistical significance was set at 0.05. Results: In our sample, the LF and canals were present in 93.33% of the CBCT analyzed, and the majority (76.64% was located above the genial tubercles. The distance from the foramen of the superior and the inferior LCs to the alveolar crest was 16.24 ± 2.82 mm and 25.49 ± 2.43 mm, respectively. The distance from the foramen of the superior canal to the inferior border of the mandible was 14 ± 2.32 mm. The mean length of the superior canal was 5.81 ± 1.6 mm and 4.25 ± 1.2 mm for the inferior one. There were no gender-related differences in the anatomic characteristics of the LF and canals except for the distance measured from the superior canal foramina to the alveolar crest where the measurement was significantly greater in males compared to females. Neither the number of canals nor the positions of the foramina were different between males and females. Conclusion: Within the limits of this study, we concluded that in our sample of Lebanese adults, there was substantial variability in the LF and canals anatomy and location.

  9. Anatomical Variations of the Blood Vascular System in Veterinary Medicine: The Internal Iliac Artery of the Dog: Part One.

    Science.gov (United States)

    Avedillo, L; Martín-Alguacil, N; Salazar, I

    2015-08-01

    Traditional veterinary anatomical models describe the branches of the caudal gluteal artery as the iliolumbar, cranial gluteal, lateral caudal, satellite of the ischiatic nerve and dorsal perineal arteries. However, some classical veterinary anatomy textbooks often indicate variations the general organization of the arterial tree, without giving any pattern of origin or illustrations of the different branching. The aim of this study was to investigate the presumptive variability of the caudal gluteal artery. Two hundred and thirty-two pelvic halves from 116 adult dogs were examined. Twelve anatomical variations were found, nine occurring in more than 5% of the dogs, and three in internal iliac artery, which means short caudal gluteal and internal pudendal arteries, was identified, while a 'perineal trunk' was observed as an interesting arterial variation. If the caudal segment alone is taken into consideration, identical vascular patterns in both hemi-pelvises are found in 17% of the dogs. Significant statistical correlation was found for four different types of anatomic variations and gender, two types of variations and body size, one type of variation for body side and one type of variation for head shape. © 2014 Blackwell Verlag GmbH.

  10. Anatomical variations of pronator teres muscle: predispositional role for nerve entrapment

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    Edie Benedito Caetano

    Full Text Available ABSTRACT OBJECTIVE: To assess the anatomical variations of the pronator teres muscle (PTM and its implication in the compression of the median nerve, which passes through the humeral and ulnar heads of the PTM. METHODS: For the present study, 100 upper limbs from human cadavers from the anatomy laboratory were dissected. Forty-six specimens were male and four, female, whose aged ranged from 28 to 77 years; 27 were white and 23, non-white. A pilot study consisting of six hands from three fresh cadaver dissections was conducted to familiarize the authors with the local anatomy; these were not included in the present study. RESULTS: The humeral and ulnar heads of PTM were present in 86 limbs. In 72 out of the 86 limbs, the median nerve was positioned between the two heads of the PTM; in 11, it passed through the muscle belly of ulnar head of the PTM, and in three, posteriorly to both heads of the PTM. When both heads were present, the median nerve was not observed as passing through the muscle belly of the humeral head of PTM. In 14 out of the 100 dissected limbs, the ulnar head of the PTM was not observed; in this situation, the median nerve was positioned posteriorly to the humeral head in 11 limbs, and passed through the humeral head in three. In 17 limbs, the ulnar head of PTM was little developed, with a fibrous band originating from the ulnar coronoid process, associated with a distal muscle component near the union with the humeral head. In four limbs, the ulnar head of the MPR was represented by a fibrous band. In both limbs of one cadaver, a fibrous band was observed between the supinator muscle and the humeral head of the PTM, passing over median nerve. CONCLUSION: The results suggest that these anatomical variations in relationship median nerve and PTM are potential factors for median nerve compression, as they narrow the space through which the median nerve passes.

  11. Digital preservation of anatomical variation: 3D-modeling of embalmed and plastinated cadaveric specimens using uCT and MRI.

    Science.gov (United States)

    Moore, Colin W; Wilson, Timothy D; Rice, Charles L

    2017-01-01

    Anatomy educators have an opportunity to teach anatomical variations as a part of medical and allied health curricula using both cadaveric and three-dimensional (3D) digital models of these specimens. Beyond published cadaveric case reports, anatomical variations identified during routine gross anatomy dissection can be powerful teaching tools and a medium to discuss several anatomical sub-disciplines from embryology to medical imaging. The purpose of this study is to document how cadaveric anatomical variation identified during routine dissection can be scanned using medical imaging techniques to create two-dimensional axial images and interactive 3D models for teaching and learning of anatomical variations. Three cadaveric specimens (2 formalin embalmed, 1 plastinated) depicting anatomical variations and an embryological malformation were scanned using magnetic resonance imaging (MRI) and micro-computed tomography (μCT) for visualization in cross-section and for creation of 3D volumetric models. Results provide educational options to enable visualization and facilitate learning of anatomical variations from cross-sectional scans. Furthermore, the variations can be highlighted, digitized, modeled and manipulated using 3D imaging software and viewed in the anatomy laboratory in conjunction with traditional anatomical dissection. This study provides an example for anatomy educators to teach and describe anatomical variations in the undergraduate medical curriculum. Copyright © 2016 Elsevier GmbH. All rights reserved.

  12. ANATOMIC VARIATIONS OF HEPATIC ARTERY: A STUDY IN 479 LIVER TRANSPLANTATIONS.

    Science.gov (United States)

    Fonseca-Neto, Olival Cirilo Lucena da; Lima, Heloise Caroline de Souza; Rabelo, Priscylla; Melo, Paulo Sérgio Vieira de; Amorim, Américo Gusmão; Lacerda, Cláudio Moura

    2017-01-01

    The incidence of anatomic variations of hepatic artery ranges from 20-50% in different series. Variations are especially important in the context of liver orthotopic transplantation, since, besides being an ideal opportunity for surgical anatomical study, their precise identification is crucial to the success of the procedure. To identify the anatomical variations in the hepatic arterial system in hepatic transplantation. 479 medical records of transplanted adult patients in the 13-year period were retrospectively analyzed, and collected data on hepatic arterial anatomy of the deceased donor. It was identified normal hepatic arterial anatomy in 416 donors (86.84%). The other 63 patients (13.15%) showed some variation. According to the Michels classification, the most frequently observed abnormalities were: right hepatic artery branch of superior mesenteric artery (Type III, n=27, 5.63%); left hepatic artery branch of the left gastric artery (Type II, n=13, 2.71%); right hepatic artery arising from the superior mesenteric artery associated with the left hepatic artery arising from the left gastric artery (Type IV, n=4, 0.83%). Similarly, in relation to Hiatt classification, the most prevalent changes were: right hepatic accessory artery or substitute of the superior mesenteric artery (Type III, n=28, 6.05%)), followed by liver ancillary left artery or replacement of gastric artery left (Type II, n=16, 3.34. Fourteen donors (2.92%) showed no anatomical abnormalities defined in classifications, the highest frequency being hepatomesenteric trunk identified in five (01.04%). Detailed knowledge of the variations of hepatic arterial anatomy is of utmost importance to surgeons who perform approaches in this area, particularly in liver transplantation, since their identification and proper management are critical to the success of the procedure. A incidência das variações anatômicas da artéria hepática varia de 20-50% em diferentes casuísticas. Elas s

  13. 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.

  14. Anatomical variations of the coeliac trunk in the homogeneous Polish population.

    Science.gov (United States)

    Torres, K; Staśkiewicz, G; Denisow, M; Pietrzyk, Ł; Torres, A; Szukała, M; Czekajska-Chehab, E; Drop, A

    2015-01-01

    The abdominal vessels show a number of abnormalities and pathologies knowledge of which is important during open as well as laparoscopic surgeries. One of the most common vessels which pattern has many variations is the coeliac trunk. The present study was undertaken on homogeneous population to assess morphology of the coeliac trunk and to evaluate the possible variability of its branches. Standard abdominal multidetector computed tomography examinations were performed on a total of 1569 patients diagnosed by 2 radiologists independently; in case of doubts common assessment was performed. The coeliac trunk followed the classic pattern in 92.7% of the cases (1455/1569 of patients). The gastrosplenic trunk was detected in 4.1% of cases (64/1569); the hepatosplenic trunk in 2.2% of cases (34/1569); the coeliac-mesenteric trunk was observed in 0.5% of cases (8/1569); the hepatogastric trunk in 0.2% of cases (4/1569); the splenomesenteric trunk was detected in 0.1% of cases (2/1569). In the next 0.1% the coeliac trunk was absent. The hepatosplenomesenteric and the coeliac-colic trunk were not observed in the study population. Vascular anatomical abnormality is usually asymptomatic hovewer, its preoperative knowledge is helpful to reduce complications like vascular bleeding when dissecting the hapato-pancreatic region. The coeliac trunk and its branches can be fast and easy evaluated in computed tomography exams performed due to various symptoms from abdominal cavity.

  15. 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. © 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.

  16. 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.

  17. Broad Anatomical Variation within a Narrow Wood Density Range--A Study of Twig Wood across 69 Australian Angiosperms.

    Science.gov (United States)

    Ziemińska, Kasia; Westoby, Mark; Wright, Ian J

    2015-01-01

    Just as people with the same weight can have different body builds, woods with the same wood density can have different anatomies. Here, our aim was to assess the magnitude of anatomical variation within a restricted range of wood density and explore its potential ecological implications. Twig wood of 69 angiosperm tree and shrub species was analyzed. Species were selected so that wood density varied within a relatively narrow range (0.38-0.62 g cm-3). Anatomical traits quantified included wood tissue fractions (fibres, axial parenchyma, ray parenchyma, vessels, and conduits with maximum lumen diameter below 15 μm), vessel properties, and pith area. To search for potential ecological correlates of anatomical variation the species were sampled across rainfall and temperature contrasts, and several other ecologically-relevant traits were measured (plant height, leaf area to sapwood area ratio, and modulus of elasticity). Despite the limited range in wood density, substantial anatomical variation was observed. Total parenchyma fraction varied from 0.12 to 0.66 and fibre fraction from 0.20 to 0.74, and these two traits were strongly inversely correlated (r = -0.86, P wood density spectrum, a fibre-parenchyma spectrum, and a vessel area spectrum. The fibre-parenchyma spectrum does not yet have any clear or convincing ecological interpretation.

  18. Broad Anatomical Variation within a Narrow Wood Density Range—A Study of Twig Wood across 69 Australian Angiosperms

    Science.gov (United States)

    Ziemińska, Kasia; Westoby, Mark; Wright, Ian J.

    2015-01-01

    Objectives Just as people with the same weight can have different body builds, woods with the same wood density can have different anatomies. Here, our aim was to assess the magnitude of anatomical variation within a restricted range of wood density and explore its potential ecological implications. Methods Twig wood of 69 angiosperm tree and shrub species was analyzed. Species were selected so that wood density varied within a relatively narrow range (0.38–0.62 g cm-3). Anatomical traits quantified included wood tissue fractions (fibres, axial parenchyma, ray parenchyma, vessels, and conduits with maximum lumen diameter below 15 μm), vessel properties, and pith area. To search for potential ecological correlates of anatomical variation the species were sampled across rainfall and temperature contrasts, and several other ecologically-relevant traits were measured (plant height, leaf area to sapwood area ratio, and modulus of elasticity). Results Despite the limited range in wood density, substantial anatomical variation was observed. Total parenchyma fraction varied from 0.12 to 0.66 and fibre fraction from 0.20 to 0.74, and these two traits were strongly inversely correlated (r = -0.86, P wood density spectrum, a fibre-parenchyma spectrum, and a vessel area spectrum. The fibre-parenchyma spectrum does not yet have any clear or convincing ecological interpretation. PMID:25906320

  19. STUDY OF ANATOMICAL VARIATIONS AND INCIDENCE OF MENTAL FORAMEN AND ACCESSORY MENTAL FORAMEN IN DRY HUMAN MANDIBLES

    OpenAIRE

    Sumit Gupta; Jagdish S. Soni

    2012-01-01

    Objectives: To provide anatomical information on the position, morphological variations and incidence of mental foramen and accessory mental foramen as they are important for dental surgeons, anaesthetists in nerve block and surgical procedures to avoid injury to neurovascular bundle in mental foramen area. Method: The present study was conducted using 120 dried human mandibles of both sexes. Size, shape and position of mental foramen and accessory mental foramen were determined using digital...

  20. AnAtomicAl vAriAtions of the cArotid Arteries in Adult KenyAns

    African Journals Online (AJOL)

    85 No. 5 May 2008. anatoMical variations of tHE carotid artEriEs in adult KEnyans d. anangwe, Bsc (anat), H. saidi, Bsc (anat), MBchB, MMed, fcs, senior lecturer, J. ogeng'o, Bsc. (anat), MBchB and K.o. awori, MBchB, MMed, department of Human anatomy, college of Health sciences, university of nairobi,. P.o. Box ...

  1. Anatomical Variations of the Blood Vascular System in Veterinary Medicine: The Internal Iliac Artery of the Dog - Part Three.

    Science.gov (United States)

    Avedillo, L; Martín-Alguacil, N; Salazar, I

    2016-06-01

    The aim of this study was to analyse and describe the variability of the umbilical artery. Two hundred and thirty-two pelvic halves from 116 adult dogs were examined. To study the permeability of the umbilical artery, ten adult dogs, nine newborns and thirteen foetuses between 35 and 50 days of gestation were also used. In relation to the origin of the umbilical artery, six anatomical variations were found. From which five involved a cranial (n = 4) or caudal (n = 1) relocation of its origin, and in one case (n = 1), the umbilical artery arose from the median sacral artery. In eight cases, the umbilical artery gave off the prostatic (n = 1) or vaginal (n = 7) arteries. The permeability of the umbilical artery was the most significant anatomical variation: permeability was detected in 45% (106 of 232 pelvic halves) of all cases, from which 36 were males and 70 females. Interestingly, an equal vascular permeability in both hemipelvises was found for 82% of the dogs, thus additional data related to such feature of the umbilical artery was also recorded. In accordance with the statistical study, the main anatomical variations described showed significant values for gender, side of the body, size and profile variables. © 2015 Blackwell Verlag GmbH.

  2. 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.

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

    Directory of Open Access Journals (Sweden)

    Nalamachu S

    2013-06-01

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

  4. Variation in leaf anatomical characters in response to air pollution in ...

    African Journals Online (AJOL)

    Dry and wet season studies of the leaf anatomy of ten plant species in the family Euphorbiaceae from three sites with different pollution levels in Southwestern Nigeria were carried out. This is with a view to establish the response of plant anatomical structures to air pollution. The species investigated were Alchornea laxiflora ...

  5. 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.

  6. Anatomical variations of the iliolumbar vein with application to the anterior retroperitoneal approach to the lumbar spine: a cadaver study.

    Science.gov (United States)

    Unruh, Kenneth P; Camp, Christopher L; Zietlow, Scott P; Huddleston, Paul M

    2008-10-01

    Objectives of this study include identification of lumbosacral venous variations, designation of a critical area of dissection for surgical exposure, and comparison between both male/female and right/left-sided anatomy. Attempts were made to provide anatomic nomenclature that accurately describes these structures. Thirty-eight iliolumbar venous systems in 20 cadavers (11 females/9 males) were dissected. Each system was identified as one of three patterns of variation: common venous trunk (combining ascending lumbar and iliolumbar venous systems) with distal veins, common venous trunk without distal veins, and venous systems without a common venous trunk. Dimensions including distances to the inferior vena cava (IVC) confluence, the obturator nerve, and the lumbosacral trunk, and venous stem length were obtained to aid surgical dissection. Differences between males and females and those between right and left sides were compared. Anterior lumbosacral venous variations could be organized into three groups. A Type 1 venous system (common venous trunk with distal veins) was most common (53% of systems). The anatomical name "lateral lumbosacral veins" adequately describes the anatomical location of these veins and does not assume a direction of venous flow or the lack of individual distal veins. A critical area bordered by the obturator nerve anteriorly, the psoas muscle laterally, the spinal column medially, and sacrum posteriorly within 8.2 cm of the IVC confluence should be defined to adequately dissect the lateral lumbosacral veins. Differences in male and female lateral lumbosacral venous anatomy do not alter surgeon's approach to the anterior lumbar spine. (c) 2008 Wiley-Liss, Inc.

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

    Directory of Open Access Journals (Sweden)

    Róger Moya

    2008-06-01

    Full Text Available 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. Rev. Biol. Trop. 56 (2: 689-704. Epub 2008 June 30.Gmelina arborea ha sido introducida y ampliamente sembrada en Costa Rica en plantaciones de rápido crecimiento. Estas nuevas condiciones ecológicas provocan variación en la anatomía del xilema de estos árboles. El presente trabajo tuvo como objetivo determinar la variación en la anatomía del xilema debido a la variación de la latitud, longitud, altitud y precipitación. Se evaluaron las dimensiones de las fibras, el porcentaje de área ocupada por el parénquima y los parámetros de los vasos y los radios. Algunas características anatómicas se mantuvieron estables con las variaciones de las

  8. Case Report: Multiple anatomical variations in the arm in an Indian ...

    African Journals Online (AJOL)

    Additionally, a small slip of accessory fibers of biceps brachii was found arising from the main bulk of the muscle and inserted on to the deep fascia of the lateral cubital region. We present multiple variations in the same limb some of which have not been reported yet. Awareness of these rare variations is therefore necessary ...

  9. Anatomical robust optimization to account for nasal cavity filling variation during intensity-modulated proton therapy: a comparison with conventional and adaptive planning strategies.

    Science.gov (United States)

    van de Water, Steven; Albertini, Francesca; Weber, Damien C; Heijmen, Ben J M; Hoogeman, Mischa S; Lomax, Antony J

    2018-01-11

    The aim of this study is to develop an anatomical robust optimization method for intensity-modulated proton therapy (IMPT) that accounts for interfraction variations in nasal cavity filling, and to compare it with conventional single-field uniform dose (SFUD) optimization and online plan adaptation. We included CT data of five patients with tumors in the sinonasal region. Using the planning CT, we generated for each patient 25 'synthetic' CTs with varying nasal cavity filling. The robust optimization method available in our treatment planning system 'Erasmus-iCycle' was extended to also account for anatomical uncertainties by including (synthetic) CTs with varying patient anatomy as error scenarios in the inverse optimization. For each patient, we generated treatment plans using anatomical robust optimization and, for benchmarking, using SFUD optimization and online plan adaptation. Clinical target volume (CTV) and organ-at-risk (OAR) doses were assessed by recalculating the treatment plans on the synthetic CTs, evaluating dose distributions individually and accumulated over an entire fractionated 50 Gy RBE treatment, assuming each synthetic CT to correspond to a 2 Gy RBE fraction. Treatment plans were also evaluated using actual repeat CTs. Anatomical robust optimization resulted in adequate CTV doses (V 95%   ⩾  98% and V 107%   ⩽  2%) if at least three synthetic CTs were included in addition to the planning CT. These CTV requirements were also fulfilled for online plan adaptation, but not for the SFUD approach, even when applying a margin of 5 mm. Compared with anatomical robust optimization, OAR dose parameters for the accumulated dose distributions were on average 5.9 Gy RBE (20%) higher when using SFUD optimization and on average 3.6 Gy RBE (18%) lower for online plan adaptation. In conclusion, anatomical robust optimization effectively accounted for changes in nasal cavity filling during IMPT, providing substantially improved CTV and

  10. Anatomical robust optimization to account for nasal cavity filling variation during intensity-modulated proton therapy: a comparison with conventional and adaptive planning strategies

    Science.gov (United States)

    van de Water, Steven; Albertini, Francesca; Weber, Damien C.; Heijmen, Ben J. M.; Hoogeman, Mischa S.; Lomax, Antony J.

    2018-01-01

    The aim of this study is to develop an anatomical robust optimization method for intensity-modulated proton therapy (IMPT) that accounts for interfraction variations in nasal cavity filling, and to compare it with conventional single-field uniform dose (SFUD) optimization and online plan adaptation. We included CT data of five patients with tumors in the sinonasal region. Using the planning CT, we generated for each patient 25 ‘synthetic’ CTs with varying nasal cavity filling. The robust optimization method available in our treatment planning system ‘Erasmus-iCycle’ was extended to also account for anatomical uncertainties by including (synthetic) CTs with varying patient anatomy as error scenarios in the inverse optimization. For each patient, we generated treatment plans using anatomical robust optimization and, for benchmarking, using SFUD optimization and online plan adaptation. Clinical target volume (CTV) and organ-at-risk (OAR) doses were assessed by recalculating the treatment plans on the synthetic CTs, evaluating dose distributions individually and accumulated over an entire fractionated 50 GyRBE treatment, assuming each synthetic CT to correspond to a 2 GyRBE fraction. Treatment plans were also evaluated using actual repeat CTs. Anatomical robust optimization resulted in adequate CTV doses (V95%  ⩾  98% and V107%  ⩽  2%) if at least three synthetic CTs were included in addition to the planning CT. These CTV requirements were also fulfilled for online plan adaptation, but not for the SFUD approach, even when applying a margin of 5 mm. Compared with anatomical robust optimization, OAR dose parameters for the accumulated dose distributions were on average 5.9 GyRBE (20%) higher when using SFUD optimization and on average 3.6 GyRBE (18%) lower for online plan adaptation. In conclusion, anatomical robust optimization effectively accounted for changes in nasal cavity filling during IMPT, providing substantially improved CTV and

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

    International Nuclear Information System (INIS)

    Amer, Maha Eshak; Heo, Min Suk; Brooks, Sharon L; Benavides, Erika

    2012-01-01

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

  12. The auriculotemporal nerve in etiology of migraine headaches: compression points and anatomical variations.

    Science.gov (United States)

    Chim, Harvey; Okada, Haruko C; Brown, Matthew S; Alleyne, Brendan; Liu, Mengyuan T; Zwiebel, Samantha; Guyuron, Bahman

    2012-08-01

    The auriculotemporal nerve has been identified as one of the peripheral trigger sites for migraine headaches. However, its distal course is poorly mapped following emergence from the parotid gland. In addition, a reliable anatomical landmark for locating the potential compression points along the course of the nerve during surgery has not been sufficiently described. Twenty hemifaces on 10 fresh cadavers were dissected to trace the course of the auriculotemporal nerve from the inferior border of the zygomatic arch to its termination in the temporal scalp. The compression points were mapped and the distances were measured from the most anterosuperior point of the external auditory meatus, which was used as a fixed anatomical landmark. Three potential compression points along the course of the auriculotemporal nerve were identified. Compression points 1 and 2 corresponded to preauricular fascial bands. Compression point 1 was centered 13.1±5.9 mm anterior and 5.0±7.0 mm superior to the most anterosuperior point of the external auditory meatus, whereas compression point 2 was centered at 11.9±6.0 mm anterior and 17.2±10.4 mm superior to the most anterosuperior point of the external auditory meatus. A significant relationship was found between the auriculotemporal nerve and superficial temporal artery (compression point 3) in 80 percent of hemifaces, with three patterns of interaction: a single site of artery crossing over the nerve (62.5 percent), a helical intertwining relationship (18.8 percent), and nerve crossing over the artery (18.8 percent). Findings from this cadaver study provide information relevant to the operative localization of potential compression points along the auriculotemporal nerve.

  13. Effects of plantation density on wood density and anatomical properties of red pine (Pinus resinosa Ait.)

    Science.gov (United States)

    J. Y. Zhu; C. Tim Scott; Karen L. Scallon; Gary C. Myers

    2007-01-01

    This study demonstrated that average ring width (or average annual radial growth rate) is a reliable parameter to quantify the effects of tree plantation density (growth suppression) on wood density and tracheid anatomical properties. The average ring width successfully correlated wood density and tracheid anatomical properties of red pines (Pinus resinosa Ait.) from a...

  14. 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

  15. [AICA anatomic variation as a factor of worse prognosis for the surgical treatment of hemi-facial spasm].

    Science.gov (United States)

    Reizinho, Carla; Casimiro, Miguel; Luís, Ana; Dominguez, Manuel

    2013-01-01

    Hemifacial spasm is a neurovascular compression syndrome. These consist in a contacting vessel (most often an artery) to a cranial nerve in cerebelar-pontine angle. The most common is trigeminal neuralgia caused by contact between the superior cerebellar artery and the trigeminal nerve, and less commonly hemifacial spasm, vertiginous syndrome by contact of the antero inferior cerebelar artery with the eighth cranial nerve, glossopharyngeal neuralgia by contact of the postero inferior cerebelar artery and the IX cranial nerve, etc. These syndromes typically occur after the fifth decade of life, when the arterial tortuosity increases due to the arteriosclerosis process. They are however associated anatomical variations of the origin and course of the arteries, which facilitate contact with the nerves of the cerebellar-pontine angle. In hemifacial spasm, the vessel most often related is antero inferior cerebelar and the authors describe a case of a rare anatomical variant in the course of the artery that motivated the development of the disease, which was identified intraoperatively on a surgical approach to the cerebellar-pontine for vascular microdescompression.

  16. Racial Variations in Prostate Cancer Molecular Subtypes and Androgen Receptor Signaling Reflect Anatomic Tumor Location.

    Science.gov (United States)

    Faisal, Farzana A; Sundi, Debasish; Tosoian, Jeffrey J; Choeurng, Voleak; Alshalalfa, Mohammed; Ross, Ashley E; Klein, Eric; Den, Robert; Dicker, Adam; Erho, Nicholas; Davicioni, Elai; Lotan, Tamara L; Schaeffer, Edward M

    2016-07-01

    Prostate cancer (PCa) subtypes based on ETS gene expression have been described. Recent studies suggest there are racial differences in tumor location, with PCa located anteriorly more often among African-American (AA) compared to Caucasian-American (CA) men. In this retrospective analysis of a multi-institutional cohort treated by radical prostatectomy (179 CA, 121 AA), we evaluated associations among molecular subtype, race, anatomic tumor location, and androgen receptor (AR) signaling. Subtype (m-ERG(+), m-ETS(+), m-SPINK1(+), or triple-negative) was determined using distribution-based outlier analysis. AR signaling was investigated using gene expression profiling of canonical AR targets. m-ERG(+) was more common in CA than AA men (47% vs 22%, pRacial differences in molecular subtypes did not persist when tumors were analyzed by location, suggesting a biologically important relationship between tumor location and subtype. Accordingly, anterior tumor location was associated with higher Decipher scores and lower global AR signaling. This study demonstrates associations among patient race, prostate cancer molecular subtypes, and tumor location. Location-specific differences in androgen regulation may further underlie these relationships. Copyright © 2015. Published by Elsevier B.V.

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

    International Nuclear Information System (INIS)

    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

    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. (author)

  18. 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.

  19. 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)

  20. Anatomical variation of the spinous and transverse processes in the caudal cervical vertebrae and the first thoracic vertebra in horses.

    Science.gov (United States)

    Santinelli, I; Beccati, F; Arcelli, R; Pepe, M

    2016-01-01

    There are scant data on the incidence of different anatomical variants of the equine caudal cervical spine, despite interest in cervical pathology. To identify morphological radiographic variation in the 6th and 7th cervical vertebrae and the first thoracic vertebra in horses of different breeds and to determine whether there are breed- and sex-related differences. Retrospective descriptive study. Radiographs of the cervical spine of 270 horses were assessed retrospectively. The Chi-square test, or Fisher's exact test when appropriate, was used to test for associations between radiographic findings and sex or breed, and residual analysis was performed to localise differences. Chi-square tests and calculation of phi coefficient (φ) were used to test for associations between different types of radiological variation. Three variants were identified in the spinous process of the 7th cervical vertebra, and 2 variants were identified in the spinous process of the first thoracic vertebra. The presence of the spinous process of the 7th cervical vertebra was associated with breed, and transposition of the ventral process of the 6th cervical vertebra onto the ventral aspect of the 7th cervical vertebra was associated with sex. The shape of the spinous process of first thoracic vertebra was associated with the shape of the spinous process of the 7th cervical vertebra and with the presence of transposition of the ventral process of the 6th cervical vertebra onto the ventral aspect of the 7th. A large number of anatomical variants can be detected radiographically in the caudal cervical area; some of these have a higher frequency, depending on sex and breed. Knowledge of the different shapes is very important in avoiding misdiagnosis of periarticular new bone formation. The spinous process of the first thoracic vertebra has 2 morphological variants. © 2015 EVJ Ltd.

  1. Anatomical Variations in Clefts of the Lip with or without Cleft Palate

    Directory of Open Access Journals (Sweden)

    K. Carroll

    2012-01-01

    Full Text Available Objective. Few orofacial cleft (OFC studies have examined the severity of clefts of the lip or palate. This study examined associations between the severity of cleft of the lip with cleft type, laterality, and sex in four regional British Isles cleft registers whilst also looking for regional variations. Design. Retrospective analysis of cleft classification in the data contained in these four cleft registers. Sample. Three thousand and twelve patients from cleft registers based in Scotland, East England, Merseyside, and Belfast were sourced from the period 2002–2010. Submucous clefts and syndromic clefts were included whilst stillbirths, abortuses, and atypical orofacial clefts were excluded. Results. A cleft of the lip in CLP patients is more likely to be complete in males. A cleft of the lip in isolated CL patients is more likely to be complete in females. Variation in the proportion of cleft types was evident between Scotland and East England. Conclusions. Association between severity of cleft of the lip and sex was found in this study with females having a significantly greater proportion of more severe clefts of the lip (CL and CLP males being more severe . This finding supports a fundamental difference between cleft aetiology between CL and CLP.

  2. A rare anatomical variation: a case of a common celiacomesenteric trunk in a cat.

    Science.gov (United States)

    Gorissen, B M C; Moens, H C; Wolschrijn, C F

    2014-08-01

    In this study, we present a cat with a common 1-cm-long celiacomesenteric trunk. The arteria hepatica branched off first from the separate arteria celiaca and gave rise to the arteria gastrica dextra and arteria gastroduodenalis. The main stem of the arteria celiaca then split into the arteria gastrica sinistra and the arteria lienalis. The arteria mesenterica cranialis extended ventrocaudally in the mesentery. This variation is due to developmental changes in the ventral splanchnic arteries, and they are quite varied. The basic architecture and perfused organs are comparable, which indicates that the presence of a common celiacomesenteric trunk is more related to individual development than to phylogeny or function. © 2013 Blackwell Verlag GmbH.

  3. Significance of anatomical variations of the lateral circumflex femoral artery for the tensor fasciae latae flapping.

    Science.gov (United States)

    Vuksanovic-Bozaric, A; Radojevic, N; Muhovic, D; Abramovic, M; Radunovic, M

    2015-01-01

    The tensor fasciae latae (TFL) muscle is commonly used in plastic and reconstructive surgery as a transpositional or a free flap, in order to repair different kinds of defects. In most cases its vascularisation is provided by an ascending branch of lateral circumflex femoral artery (LCFA), which gives different numbers of branches and enters the TFL muscle in different manners. The represented study deals with the arterial vascularisation of the TFL muscle: the entrance of the vascular stalk branches; variations of the LCFA bifurcation's angle; and the skin area of vascularisation. The study was performed on both lower limbs of a 100 foetal and 10 adult cadavers. The LCFA was injected with micropaque solution, afterwards fixed and preserved in 10% formalin solution. Microdissection was performed under magnifying glass and surgical microscope. Analysis of adult cadavers was performed to determine the skin area vascularised by perforating blood vessels from the TFL muscle, by injecting methylene-blue dye into the artery, prior to which all branches of the LCFA, besides the ascending branch, were ligated. The research of a 100 foetal cadavers showed that the LCFA with its ascending branch ensured the blood supply to the muscle. In 85% it gave two branches, the ascending and the descending one, with the angle of bifurcation circa 90o in 73% of cases. The ascending branch can give 0 or more terminal branches, or even form an arterial net. Skin area affected with dye ranged from 18 × 22 cm to 23 × 28 cm and is in positive correlation with the LCFA length and diameter. The understanding of the presented variations have an exceptional significance in planning and applying the TFL flap, especially free flap, in successful repairing and covering the defects, as well as in preventing postoperative complications.

  4. Three-Dimensional Evaluation of the Anatomic Variations of the Femoral Vein and Popliteal Vein in Relation to the Accompanying Artery by Using CT Venography

    Energy Technology Data Exchange (ETDEWEB)

    Park, Eun Ah; Chung, Jin Wook; Lee, Whal; Yin, Yong Hu; Ha, Jung Won; Kim, Sang Joon; Park, Jae Hyung [Seoul National University Hospita, Seoul (Korea, Republic of)

    2011-06-15

    We wanted to describe the three-dimensional (3D) anatomic variations of the femoral vein (FV) and popliteal vein (PV) in relation to the accompanying artery using CT venography. We performed a retrospective review of 445 bilateral (890 limbs) lower limb CT venograms. After the 3D relationship between the FV and PV and accompanying artery was analyzed, the presence or absence of variation was determined and the observed variations were classified. In each patient, the extent and location of the variations and the location of the adductor hiatus were recorded to investigate the regional frequency of the variations. There were four distinct categories of variations: agenesis (3 limbs, 0.3%), multiplication (isolated in the FV: 190 limbs, 21%; isolated in the PV: 14 limbs, 2%; and in both the FV and PV: 51 limbs, 6%), anatomical course variation (75 limbs, 8%) and high union of the tibial veins (737 limbs, 83%). The course variations included medial malposition (60 limbs, 7%), anterior rotation (11 limbs, 1%) and posterior rotation (4 limbs, 0.4%). Mapping the individual variations revealed regional differences in the pattern and frequency of the variations. CT venography helps to confirm a high incidence of variations in the lower limb venous anatomy and it also revealed various positional venous anomalies in relation to the respective artery.

  5. Incidence and anatomical variations of accessory navicular bone in patients with foot pain: A retrospective radiographic analysis.

    Science.gov (United States)

    Kalbouneh, Heba; Alajoulin, Omar; Alsalem, Mohammad; Humoud, Noor; Shawaqfeh, Jamil; Alkhoujah, Mohammad; Abu-Hassan, Hana; Mahafza, Waleed; Badran, Darwish

    2017-05-01

    The accessory navicular (AN) is an accessory ossicle anatomically located on the medial side of the foot, proximal to the navicular and continuous with the tibialis posterior tendon. It is occasionally a source of pain and local tenderness. Knowledge of the AN and its morphological variations can help identify the source of a patient's symptoms and prevent misinterpreting them as fractures. Foot radiographs from 1,240 patients who presented in two centers with chronic foot pain, or persistent pain developed after trauma, were retrospectively reviewed to determine the incidence and variations of the AN in relation to gender. The AN was found in 20.9% (259/1240). Among 259 feet with AN, Type 1 was identified in 25.4% (66/259), Type 2 in 42.4% (110/259) (20.0% (52/259) Type 2 A and 22.4% (58/259) Type 2B), and Type 3 in 32.0% (83/259). After 13 patients with incomplete medical records had been excluded, the remaining records showed that foot pain was associated with an AN in 10.6% of patients (26/246). In 1.2% of cases, two additional ossicles were found proximal to the navicular, possibly the result of multiple ossification centers that did not unite at the time of development. Patient symptomatology was related to the presence of an AN in 2% of patients with chronic foot pain. The AN could vary morphologically. Our data can enhance our diagnostic skills in detecting these ossicles. Clin. Anat. 30:436-444, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

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

    International Nuclear Information System (INIS)

    Lee, Min Sun; Lee, Jee Eun; Hwang, Ji Young; Shim, Sung Shine; Yoo, Jeong Hyun; Suh, Jeong Soo; Park, Jae Young

    2006-01-01

    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

  7. 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

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

    OpenAIRE

    Ghorbani, Ahmad; Forouzesh, Mehdi; Kazemifar, Amir Mohammad

    2014-01-01

    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, ...

  9. Extractive and anatomical wood structure effects on mechanical properties of Caoba wood (Swietenia macrophylla King)

    International Nuclear Information System (INIS)

    Arevalo Fuentes Rosven Libardo; Hernandez Roger

    2008-01-01

    The compression tangential to grain of samples of mahogany wood from Peru was examined at different relative humidity levels at 25 Celsius degrade to determine the influence of both extractives and anatomical structure. Matched samples were used to assess the percentage of extractive components by extraction with solvents of increasing polarity: cyclohexane, dichloromethane, acetone, methanol and hot water. Additionally, fourteen anatomical parameters were determined by image analysis. Stepwise regression analysis concluded that mainly anatomical features, such as rays and vessels, rather than extractives, affect the mechanical behaviour of mahogany. These findings are agree with earlier results showing a negative effect of large and multiseriate rays on the mechanical properties of wood when loaded perpendicularly to their long axis. The influence of lumen located extracts soluble in dichloromethane might disallow deformations. Finally, it is postulated that hot water extracts may play a plasticizing role in this species.

  10. Effect of industrial effluents on the growth and anatomical structures ...

    African Journals Online (AJOL)

    The authors investigated the impact of industrial effluents from 5 different industrial concerns in Lagos, Nigeria on Okra (Abelmoschus esculentus). During the study, it was observed that these effluents induced detrimental effects on the flowering, fruiting, stem length, leaf width and leaf length of okra. Other parameters ...

  11. Effect of industrial effluents on the growth and anatomical structures ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-07-20

    Jul 20, 2009 ... The authors investigated the impact of industrial effluents from 5 different industrial concerns in Lagos,. Nigeria on Okra (Abelmoschus esculentus). During the study, it was observed that these effluents induced detrimental effects on the flowering, fruiting, stem length, leaf width and leaf length of okra.

  12. Salt effect on physiological, biochemical and anatomical structures ...

    African Journals Online (AJOL)

    Yomi

    2012-04-03

    Apr 3, 2012 ... In this study, we evaluated the salt concentration effect on plant growth, mineral composition, ... absence of salt. This was accompanied by an increase in the length of palisade cells, and the width of spongy collenchyma lacuna. The stem had a subquadrangular shape .... formation was recorded at 470 nm.

  13. 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…

  14. A Computational Model Quantifies the Effect of Anatomical Variability on Velopharyngeal Function

    Science.gov (United States)

    Inouye, Joshua M.; Perry, Jamie L.; Lin, Kant Y.; Blemker, Silvia S.

    2015-01-01

    Purpose: This study predicted the effects of velopharyngeal (VP) anatomical parameters on VP function to provide a greater understanding of speech mechanics and aid in the treatment of speech disorders. Method: We created a computational model of the VP mechanism using dimensions obtained from magnetic resonance imaging measurements of 10 healthy…

  15. 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.

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

    Science.gov (United States)

    Ghorbani, Ahmad; Forouzesh, Mehdi; Kazemifar, Amir Mohammad

    2014-01-01

    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.

  17. 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.

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

    Directory of Open Access Journals (Sweden)

    DZOMEKU BELOVED MENSAH

    2012-12-01

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

  19. Separation of bones from chest radiographs by means of anatomically specific multiple massive-training ANNs combined with total variation minimization smoothing.

    Science.gov (United States)

    Sheng Chen; Suzuki, Kenji

    2014-02-01

    Most lung nodules that are missed by radiologists as well as computer-aided detection (CADe) schemes overlap with ribs or clavicles in chest radiographs (CXRs). The purpose of this study was to separate bony structures such as ribs and clavicles from soft tissue in CXRs. To achieve this, we developed anatomically specific multiple massive-training artificial neural networks (MTANNs) combined with total variation (TV) minimization smoothing and a histogram-matching-based consistency improvement method. The anatomically specific multiple MTANNs were designed to separate bones from soft tissue in different anatomic segments of the lungs. Each of the MTANNs was trained with the corresponding anatomic segment in the teaching bone images. The output segmental images from the multiple MTANNs were merged to produce an entire bone image. TV minimization smoothing was applied to the bone image for reduction of noise while preserving edges. This bone image was then subtracted from the original CXR to produce a soft-tissue image where bones were separated out. This new method was compared with conventional MTANNs with a database of 110 CXRs with nodules. Our new anatomically specific MTANNs separated rib edges, ribs close to the lung wall, and the clavicles from soft tissue in CXRs to a substantially higher level than did the conventional MTANNs, while the conspicuity of lung nodules and vessels was maintained. Thus, our technique for bone-soft-tissue separation by means of our new MTANNs would be potentially useful for radiologists as well as CADe schemes in detection of lung nodules on CXRs.

  20. 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 < 0.05). Consequently, there was a significant reduction of the percentage of the volume receiving the prescribed dose (V100) of CTV1 and GTVnd, which was more prominent after the first 15 fractions treatment compared to that between fraction 16 and 25 (p < 0.05). Additionally, there was a significant increase in the mean dose (Dmean) and percentage of volume receiving ≥ 30 Gy (V30) to the bilateral parotid in the first 15 fractions (p < 0.05), but not between 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 < 0.05), the increase of the percent of spinal cord volume receiving ≥ 40 Gy (V40) was significantly higher in the first 15 fractions compared to that between fraction 16 and 25 (p < 0.05). Based on the dose constraint criterion in the RTOG0225 protocol, a total 39.1% (9/23) of phantom plan 1 (generated by applying the beam configurations of the original IMRT treatment plan to the anatomy of the second CT scan) and 17.4% (4/23) of phantom 2 (generated by applying the beam configurations of the replan 1 to the anatomy of the third CT scan) were out of limit for the dose to the normal critical structures. In conclusion, our data indicated that

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

    International Nuclear Information System (INIS)

    Qi, X. Sharon; Santhanam, Anand; Neylon, John; Min, Yugang; Armstrong, Tess; Sheng, Ke; Staton, Robert J.; Pukala, Jason; Pham, Andrew; Low, Daniel A.; Lee, Steve P.; Steinberg, Michael; Manon, Rafael; Chen, Allen M.; Kupelian, Patrick

    2015-01-01

    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

  2. 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

  3. 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:…

  4. Image guided radiotherapy: equipment specifications and performance - an analysis of the dosimetric consequences of anatomic variations during head-and-neck radiotherapy treatment

    International Nuclear Information System (INIS)

    Marguet, Maud

    2009-01-01

    Anatomic variations during head-and-neck radiotherapy treatment may compromise the delivery of the planned dose distribution, particularly in the case of IMRT treatments. The aim of this thesis was to establish 'dosimetric indicators' to identify patients who delivered dose deviates from the planned dose, to allow an eventual re-optimisation of the patient's dosimetry, if necessary, during the course of their radiotherapy treatment. These anatomic variations were monitored by regular acquisition of 3D patient images using an onboard imaging system, for which a rigorous quality control program was implemented. The patient dose distribution analysis and comparison was performed using a modified gamma index technique which was named gammaLSC3D. This improved gamma index technique quantified and identified the location of changes in the dose distribution in a stack of 2D images, with particular reference to the target volume (PTV) or organs at risk (parotids). The changes observed in the dose distribution for the PTV or parotids were then analysed and presented in the form of gamma-volume histograms in order to facilitate the follow up of dosimetric changes during the radiotherapy treatment. This analysis method has been automated, and is applicable in clinical routine to follow dose variations during head and neck radiotherapy treatment. (author) [fr

  5. The role of the circle of Willis in internal carotid artery stenosis and anatomical variations: a computational study based on a patient-specific three-dimensional model.

    Science.gov (United States)

    Zhu, Guangyu; Yuan, Qi; Yang, Jian; Yeo, Joon Hock

    2015-11-25

    The aim of this study is to provide better insights into the cerebral perfusion patterns and collateral mechanism of the circle of Willis (CoW) under anatomical and pathological variations. In the current study, a patient-specific three-dimensional computational model of the CoW was reconstructed based on the computed tomography (CT) images. The Carreau model was applied to simulate the non-Newtonian property of blood. Flow distributions in five common anatomical variations coexisting with different degrees of stenosis in the right internal carotid artery (RICA) were investigated to obtain detailed flow information. With the development of stenosis in unilateral internal carotid artery (ICA), the cerebral blood supply decreased when the degree of stenosis increased. The blood supply of the ipsilateral middle cerebral artery (MCA) was most affected by the stenosis of ICA. The anterior communicating artery (ACoA) and ipsilateral posterior communicating artery (PCoA) functioned as the important collateral circulation channels when unilateral stenosis occurred. The blood flow of the anterior circulation and the total cerebral blood flow (CBF) reached to the minimum in the configuration of the contralateral proximal anterior cerebral artery (A1) absence coexisting with unilateral ICA stenosis. Communicating arteries provided important collateral channels in the complete CoW when stenosis in unilateral ICA occurred. The cross-flow in the ACoA is a sensitive indicator of the morphological change of the ICA. The collateral function of the PCoA on the affected side will not be fully activated until a severe stenosis occurred in unilateral ICA. The absence of unilateral A1 coexisting with the stenosis in the contralateral ICA could be the most dangerous configuration in terms of the total cerebral blood supply. The findings of this study would enhance the understanding of the collateral mechanism of the CoW under different anatomical variations.

  6. Effect of local background anatomical patterns on the detection of subtle lung nodules in chest radiographs

    Science.gov (United States)

    Samei, Ehsan; Flynn, Michael J.; Eyler, William R.; Peterson, Edward

    1998-04-01

    Anatomical noise in chest radiography, created by the projection of anatomical features in the thorax such as ribs and pulmonary vessels, greatly influences the detection of subtle lung nodules in chest radiographs. Detection may be hindered by 1) the 'global' statistical characteristics of the background in relation to the signal associated withthe nodule, and/or 2) the interference of the 'local' background pattern with the nodule signal. This investigation aimed at assessing the influence of the latter process in the detection of subtle lung nodules. Six 8 X 8 cm images were extracted from the lung regions o six digital chest radiographs of normal patients from our clinic. Simulated nodules emulating the radiographic characteristics of subtle tissue-equivalent lesions ranging in size from 3.2 to 6.4 mm were numerically superimposed on the images. For each of the six lung images, a set of thirty-one processed images were produced, six containing no nodule, and the remaining 25 containing single nodules of five different sizes placed at five different locations within 6 mm of the center. The variation in location allowed different local background patterns to overlay the nodules. An observer detection study was then performed using 14 experienced radiologists. The observer data were analyzed to determine the variation in detectability with nodule location for all five sizes of the nodules. The preliminary results indicate that the variation in detectability of a nodule due to the influence of its local background surroundings is equivalent to that caused by changing its CD product by a factor of 4.45.

  7. 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.

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

    OpenAIRE

    MOYA, Roger; FO, Mario Tomazello

    2008-01-01

    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 anato...

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

    Science.gov (United States)

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

    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; 90º, 45º and 0º, 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 90º, 45º and 0º, respectively. Pearson correlation results were r = -0.716 and P 0.05 according the subject’s BMI. 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. PMID:18837088

  10. Rotation effect and anatomic landmark accuracy for midline placement of lumbar artificial disc under fluoroscopy.

    Science.gov (United States)

    Mikhael, Mark; Brooks, Jaysson T; Akpolat, Yusuf T; Cheng, Wayne K

    2017-03-01

    Total disc arthroplasty can be a viable alternative to fusion for degenerative disc disease of the lumbar spine. The correct placement of the prosthesis within 3 mm from midline is critical for optimal function. Intra-operative radiographic error could lead to malposition of the prosthesis. The objective of this study was first to measure the effect of fluoroscopy angle on the placement of prosthesis under fluoroscopy. Secondly, determine the visual accuracy of the placement of artificial discs using different anatomical landmarks (pedicle, waist, endplate, spinous process) under fluoroscopy. Artificial discs were implanted into three cadaver specimens at L2-3, L3-4, and L4-L5. Fluoroscopic images were obtained at 0°, 2.5°, 5°, 7.5°, 10°, and 15° from the mid axis. Computerized tomography (CT) scans were obtained after the procedure. Distances were measured from each of the anatomic landmarks to the center of the implant on both fluoroscopy and CT. The difference between fluoroscopy and CT scans was compared to evaluate the position of prosthesis to each anatomic landmark at different angles. The differences between the fluoroscopy to CT measurements from the implant to pedicle was 1.31 mm, p fluoroscopy angle was greater than 7.5°, the difference between fluoroscopy and CT measurements was greater than 3 mm for all landmarks. A fluoroscopy angle of 7.5° or more can lead to implant malposition greater than 3 mm. The pedicle is the most accurate of the anatomic landmarks studied for placement of total artificial discs in the lumbar spine.

  11. Normal Anatomical Features and Variations of the Vertebrobasilar Circulation and Its Branches: An Analysis with 64-Detector Row CT and 3T MR Angiographies

    Science.gov (United States)

    Akgun, Veysel; Bozkurt, Yalcin; Hamcan, Salih; Sari, Sebahattin; Akgun, Hakan

    2013-01-01

    Purpose. To determine the normal anatomical features and variations of the vertebrobasilar circulation and its branches in patients who underwent multidetector computed tomography (CT) or magnetic resonance (MR) angiographies of the brain. Methods. 135 patients (male, 83 and female, 52; mean age, 50.1 years) who underwent CT (n = 71) or MR (n = 64) angiographies of the vertebrobasilar vasculature for various reasons were analyzed retrospectively. The right and left distal vertebral arteries (VAs), posterior inferior cerebellar arteries (PICAs), anterior inferior cerebellar arteries (AICAs), superior cerebellar arteries (SCAs), posterior cerebral arteries (PCAs), and posterior communicating arteries (PCoAs) were analyzed individually. Results. In 24.4% of the cases (33/135) right PICA, in 19.3% of the cases (26/135) left PICA, in 17.8% of the cases (24/135) right AICA, and in 18.5% of the cases (25/135) left AICA were absent. In cases without PICA or AICA, there was a statistically significant, moderately or well-developed AICA or PICA on the same side, respectively (P < 0.001). The most common variation was isolated absence of right PICA and was seen in 17.8% of the cases. Conclusions. The anatomic features of the branches of the vertebrobasilar circulation may be different from well-known normal anatomy. CT and MR angiographies allow a precise and detailed evaluation of vertebrobasilar circulation. PMID:24023533

  12. Anatomical imaging for radiotherapy

    International Nuclear Information System (INIS)

    Evans, Philip M

    2008-01-01

    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. (topical review)

  13. Human movement analysis using stereophotogrammetry. Part 4: assessment of anatomical landmark misplacement and its effects on joint kinematics.

    Science.gov (United States)

    Della Croce, Ugo; Leardini, Alberto; Chiari, Lorenzo; Cappozzo, Aurelio

    2005-02-01

    Estimating the effects of different sources of error on joint kinematics is crucial for assessing the reliability of human movement analysis. The goal of the present paper is to review the different approaches dealing with joint kinematics sensitivity to rotation axes and the precision of anatomical landmark determination. Consistent with the previous papers in this series, the review is limited to studies performed with video-based stereophotogrammetric systems. Initially, studies dealing with estimates of precision in determining the location of both palpable and internal anatomical landmarks are reviewed. Next, the effects of anatomical landmark position uncertainty on anatomical frames are shown. Then, methods reported in the literature for estimating error propagation from anatomical axes location to joint kinematics are described. Interestingly, studies carried out using different approaches reported a common conclusion: when joint rotations occur mainly in a single plane, minor rotations out of this plane are strongly affected by errors introduced at the anatomical landmark identification level and are prone to misinterpretation. Finally, attempts at reducing joint kinematics errors due to anatomical landmark position uncertainty are reported. Given the relevance of this source of errors in the determination of joint kinematics, it is the authors' opinion that further efforts should be made in improving the reliability of the joint axes determination.

  14. Callosal anatomical and effective connectivity between primary motor cortices predicts visually cued bimanual temporal coordination performance.

    Science.gov (United States)

    Wahl, Mathias; Lauterbach-Soon, Birgit; Hattingen, Elke; Hübers, Annemarie; Ziemann, Ulf

    2016-09-01

    Default in-phase coupling of hand movements needs to be suppressed when temporal coordination is required for out-of-phase bimanual movements. There is lack of knowledge on how the brain overrides these default in-phase movements to enable a required interval of activity between hands. We used a visually cued bimanual temporal coordination (vc-BTC) paradigm with a constant rhythmical time base of 1 s, to test the accuracy of in-phase and out-of-phase (0.1, 0.2,…,0.9) finger tapping. We hypothesized that (1) stronger anatomical and effective interhemispheric connectivity between the hand areas of the primary motor cortex (M1HAND) predict higher temporal offsets between hands in the out-of-phase conditions of the vc-BTC; (2) patients with relapsing-remitting multiple sclerosis (RRMS) and clinically isolated syndrome (CIS) have reduced interhemispheric connectivity and altered between-hand coupling. Anatomical connectivity was determined by fractional anisotropy of callosal hand motor fibers (FA-hCMF). Effective connectivity was probed by short interval interhemispheric inhibition (S-IHI) using paired-coil transcranial magnetic stimulation (TMS). In healthy subjects, higher FA-hCMF and S-IHI correlated with higher temporal offsets between hands in the out-of-phase conditions of the tapping test. FA-hCMF was reduced in patients with RRMS but not in CIS, while S-IHI was reduced in both patient groups. These abnormalities were associated with smaller temporal offsets between hands leading to less deviation from the required phasing in the out-of-phase tapping conditions. Findings provide multiple levels of evidence that callosal anatomical and effective connectivity between the hand areas of the motor cortices play important roles in visually cued bimanual temporal coordination performance.

  15. The anatomical variation of the circulus arteriosus cerebri in a cadaver cohort representing the population dynamics of the Western Cape.

    Science.gov (United States)

    Cilliers, Karen; Vorster, Willie; Page, Benedict John

    2017-09-05

    The literature revealed a connection between the variations of the Circulus arteriosus cerebri (CAC) and cerebrovascular disease, ischemia, stroke, aneurysms and atherosclerosis. The diameters of the vessels forming the CAC have been classified into 22 types by previous authors. The aim of this study was to assess the variation of the CAC (diameter, length and anomalies) in a cadaver cohort representing the population of the Western Cape. Thirty-nine subjects (female n = 11, male n = 28) who had died of causes unrelated to brain trauma, were obtained from Stellenbosch University. Additionally, a pilot study was done on 20 specimens. The CAC were removed and fixed for three weeks in 10% buffered formaldehyde. Digital images were taken and the vessels were measured using Adobe Creative Suite 5: Extended edition (Photoshop). The normal diameter (type 1) was observed in 41% of specimens and type 4 (hypoplastic posterior communicating artery) was observed in 23.1%. One case (bilateral hypoplastic posterior communicating arteries and a hypoplastic right posterior cerebral artery) was classified as "other", since it could not be classified into the 22 types. Additional variations included duplication (17.9%) and one point fusion (15.4%) of the anterior communicating artery. Studies have shown that about half of a healthy population have a typical CAC (normal diameter and no anomalies). In the present study the prevalence of a typical CAC was only 15.4%. Studies can only be compared if the same definitions for variations are used. The knowledge of these variations is important in endarterectomy, stenting head and neck surgery and angiography.

  16. The right vertebral artery originating from the right occipital artery and the absence of the transverse foramen: a rare anatomical variation.

    Science.gov (United States)

    Öner, Zülal; Öner, Serkan; Kahraman, Ayşegül Sağır

    2017-12-01

    Variations in the origin of the vertebral artery (VA) is a congenital anomaly that occurs during embryological development. Multiple variations related to VA origin have been reported in the literature. Abnormal VA origin is usually determined as incidental findings during angiographic or postmortem anatomical studies. Although most of the cases are asymptomatic, in patients with VA anomaly symptoms such as dizziness have been described. The anomalous variation in the origin of the right VA is rare and separated into three categories: (1) originating from the aorta, (2) originating from the carotid arteries, (3) duplicated origin. In this case, we aimed to present the right VA originating from the right occipital artery and concomitant anomalies of the transverse foramen that have not been reported previously according to our knowledge in literature. In a 32-year-old female patient referred to our hospital because of dizziness, the right VA was not observed on magnetic resonance imaging and computed tomography angiography (CTA) examination was performed. CTA showed hypoplasia of the right transverse foramen at the levels of the C1, C5 and C6 vertebrae and aplasia of the right transverse foramen at the levels of the C2, C3 and C4 vertebrae. The right VA originating from the right occipital artery continues to its normal course by entering the cranium through the foramen magnum at the level of the atlantooccipital junction.

  17. The dorsal sagittal venous sinus anatomical variations in brachycephalic, dolichocephalic, and mesocephalic dogs and their significance for brain surgery.

    Science.gov (United States)

    Carreira, L Miguel; Ferreira, António; Burilo, Fernando Liste

    2011-11-01

    Dorsal sagittal venous sinus (DSVS) is an encephalic structure located in the midline of brain dorsal surface, starting behind the frontal venous sinus and following the brain falx in its extension. Knowing DSVS morphology and cranial-cerebral relationships it is very important for surgeon when he is planning the placement of craniotomies, in order to prevent the damage of this structure. The main purpose of this study were to establish craniometric points that can be used as key points of neurosurgical importance providing an anatomic framework to brain access regarding the localization of DSVS, and to characterize the morphology of DSVS in the three groups considered in study according their type of skull (brachycephalic-B, dolychocephalic-D and mesocephalic-M). The study was performed on 138 formalin-fixed cerebral hemispheres of 69 adult dog cadavers (23 of each group) which had been removed from the skulls after the introduction of plastic catheters through properly positioned burr holes placed on the five craniometric points considered: asterion(ast), bregma(br), glabella(g), stephanion(st) and pterion(pt). From the three groups, DSVS length and width were different, his geometry in B assumed a triangular appearance and in D, M a "butterfly" shape. From all craniometric points considered, only bregma (br) can be useful as a landmark to delimitate DSVS morphology in all three groups. Asterion in M, stephanion in B, glabella and pterion in all three groups, can not be used to compose a framework that help to understand skull surface projection of DSVS morphology, since their measurements were not uniform. Copyright © 2011 Wiley-Liss, Inc.

  18. The effect of intraoperative fluoroscopy on the accuracy of femoral tunnel placement in single-bundle anatomic ACL reconstruction.

    Science.gov (United States)

    Inderhaug, Eivind; Larsen, Allan; Waaler, Per Arne; Strand, Torbjørn; Harlem, Thomas; Solheim, Eirik

    2017-04-01

    The purpose of the current study was to investigate the potential effect of intraoperative fluoroscopy on the accuracy of femoral tunnel placement in anatomic ACL reconstruction, using an ideal anatomic point as reference and evaluating postoperative tunnel placement based on 3D CT. An experienced ACL surgeon, using the anatomic approach for femoral tunnel placement, relying on intraarticular landmarks and remnants of the torn ACL-and novel to the fluoroscopic assist-was introduced to its use. A prospective series of patients was included where group 1 (without fluoroscopy) and group 2 (with fluoroscopy) both had postoperative CT scans so that femoral tunnel position could be evaluated and compared to an ideal tunnel centre based on anatomic studies by using the Bernard and Hertel grid. Group 2, where fluoroscopy was used, had a mean femoral tunnel that was closer to the ideal anatomic centre than group 1. In the Bernard and Hertel grid, the distance in the high-low axis (y-axis) was found significantly closer (P = 0.001), whilst the deep-shallow axis (x-axis) and a total absolute distance were not significantly closer to the ideal described anatomic centre. Intraoperative fluoroscopy was found effective as an aid for placing the femoral tunnel in a more accurate position, as compared to a desired anatomic centre. Although the concept of the "one-size-fits-all" approach for tunnel placement is debatable, the avoidance of grossly misplaced tunnels is the benefit of using fluoroscopy during ACL reconstruction. The authors hold that fluoroscopy is readily available, safe and easy to use and therefore a good aid in the anatomic approach for graft tunnel placement, for example, in a learning situation, in revision cases and when performing low volumes of such surgery. III.

  19. Modeling the pharyngeal anatomical effects on breathing resistance and aerodynamically generated sound.

    Science.gov (United States)

    Xi, Jinxiang; Si, Xiuhua; Kim, JongWon; Su, Guoguang; Dong, Haibo

    2014-07-01

    The objective of this study was to systematically assess the effects of pharyngeal anatomical details on breathing resistance and acoustic characteristics by means of computational modeling. A physiologically realistic nose-throat airway was reconstructed from medical images. Individual airway anatomy such as the uvula, pharynx, and larynx was then isolated for examination by gradually simplifying this image-based model geometry. Large eddy simulations with the FW-H acoustics model were used to simulate airflows and acoustic sound generation with constant flow inhalations in rigid-walled airway geometries. Results showed that pharyngeal anatomical details exerted a significant impact on breathing resistance and energy distribution of acoustic sound. The uvula constriction induced considerably increased levels of pressure drop and acoustic power in the pharynx, which could start and worsen snoring symptoms. Each source anatomy was observed to generate a unique spectrum with signature peak frequencies and energy distribution. Moreover, severe pharyngeal airway narrowing led to an upward shift of sound energy in the high-frequency range. Results indicated that computational aeroacoustic modeling appeared to be a practical tool to study breathing-related disorders. Specifically, high-frequency acoustic signals might disclose additional clues to the mechanism of apneic snoring and should be included in future acoustic studies.

  20. Density variation of parotid glands during IMRT for head–neck cancer: Correlation with treatment and anatomical parameters

    International Nuclear Information System (INIS)

    Fiorino, Claudio; Rizzo, Giovanna; Scalco, Elisa; Broggi, Sara; Belli, Maria Luisa; Dell’Oca, Italo; Dinapoli, Nicola; Ricchetti, Francesco; Rodriguez, Aldo Mejia; Di Muzio, Nadia; Calandrino, Riccardo; Sanguineti, Giuseppe; Valentini, Vincenzo; Cattaneo, Giovanni Mauro

    2012-01-01

    Purpose: Measuring parotid density changes in patients treated with IMRT for head–neck cancer (HNC) and assessing correlation with treatment-related parameters. Patients and materials: Data of 84 patients treated with IMRT for different HNC were pooled from three institutions. Parotid deformation and average Hounsfield number changes (ΔHU) were evaluated through MVCT (with Helical Tomotherapy) or diagnostic kVCT images taken at the treatment start/end. Parotids were delineated in the first image and propagated to the last using a previously validated algorithm based on elastic registration. The correlation between ΔHU and several treatment-related parameters was tested; then, logistic uni- and multi-variate analyses taking “large” ΔHU as end-point were carried out. Due to the better image quality, analyses were repeated considering only kVCT data. Results: ΔHU was negative in 116/168 parotids (69%; for kVCT patients: 72/92, 78%). The average ΔHU was significantly different from zero (−7.3, 0.20–0.25 HU/fraction, p m ean), and with neck thickness variation; these correlations were much stronger for kVCT data. Logistic analyses considering ΔHU m ean < 0.68) and initial neck thickness to be the most predictive variables (p < 0.0005, AUC = 0.683; AUC = 0.776 for kVCT); the odd ratio of large vs moderate/small parotid deformation was 3.8 and 8.0 for the whole and the kVCT population respectively. Conclusions: Parotid density reduced in most patients during IMRT and this phenomenon was highly correlated with parotid deformation. The individual assessment of density changes was highly reliable just with diagnostic KvCT. Density changes should be considered as an additional objective measurement of early parotid radiation-induced modifications; further research is warranted.

  1. 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.)

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

    International Nuclear Information System (INIS)

    Wang, Yi; Cheng, Cheng; Wang, Lu; Li, Ran; Chen, Jin-hua; Gong, Shui-gen

    2014-01-01

    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.)

  3. Anatomical variations of the deep head of Cruveilhier of the flexor pollicis brevis and its significance for the evolution of the precision grip.

    Science.gov (United States)

    Dunlap, Samuel S; Aziz, M Ashraf; Ziermann, Janine M

    2017-01-01

    Cruveilhier described in 1834 the human flexor pollicis brevis (FPB), a muscle of the thenar compartment, as having a superficial and a deep head, respectively, inserted onto the radial and ulnar sesamoids of the thumb. Since then, Cruveilhier's deep head has been controversially discussed. Often this deep head is confused with Henle's "interosseous palmaris volaris" or said to be a slip of the oblique adductor pollicis. In the 1960s, Day and Napier described anatomical variations of the insertions of Cruveilhier's deep head, including its absence, and hypothesized, that the shift of the deep head's insertion from ulnar to radial facilitated "true opposability" in anthropoids. Their general thesis for muscular arrangements underlying the power and precision grip is sound, but they did not delineate their deep head from Henle's muscle or the adductor pollicis, and their description of the attachments of Cruveilhier's deep head were too vague and not supported by a significant portion of the anatomical literature. Here, we reinvestigated Cruveilhier's deep head to resolve the controversy about it and because many newer anatomy textbooks do not describe this muscle, while it is often an obvious functionally (writing, texting, precision grip) and clinically significant thenar muscle. For the first time, we empirically delineated Cruveilhier's deep head from neighboring muscles with which it was previously confused. We observed 100% occurrence of the uncontested deep head in 80 human hands, displaying a similar variability of insertions as Day and Napier, but in significantly different numbers. Furthermore, we found variability in the origin and included as important landmarks the trapezoid and the ligamentum carpi radiatum. We tested the assertion regarding the evolutionary morphology and its role in the improvements in thumb movements during various precision grips. Our overall conclusions differ with respect to the developmental and evolutionary origin of the FPB

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

    Science.gov (United States)

    Nemati, Somayeh; Ashouri Moghadam, Anahita; Dalili Kajan, Zahra; Mohtavipour, Seyedeh Tahereh; Amouzad, Hasan

    2016-06-01

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

  5. Integration of anatomical and external response mappings explains crossing effects in tactile localization: A probabilistic modeling approach.

    Science.gov (United States)

    Badde, Stephanie; Heed, Tobias; Röder, Brigitte

    2016-04-01

    To act upon a tactile stimulus its original skin-based, anatomical spatial code has to be transformed into an external, posture-dependent reference frame, a process known as tactile remapping. When the limbs are crossed, anatomical and external location codes are in conflict, leading to a decline in tactile localization accuracy. It is unknown whether this impairment originates from the integration of the resulting external localization response with the original, anatomical one or from a failure of tactile remapping in crossed postures. We fitted probabilistic models based on these diverging accounts to the data from three tactile localization experiments. Hand crossing disturbed tactile left-right location choices in all experiments. Furthermore, the size of these crossing effects was modulated by stimulus configuration and task instructions. The best model accounted for these results by integration of the external response mapping with the original, anatomical one, while applying identical integration weights for uncrossed and crossed postures. Thus, the model explained the data without assuming failures of remapping. Moreover, performance differences across tasks were accounted for by non-individual parameter adjustments, indicating that individual participants' task adaptation results from one common functional mechanism. These results suggest that remapping is an automatic and accurate process, and that the observed localization impairments in touch result from a cognitively controlled integration process that combines anatomically and externally coded responses.

  6. Anatomical localization and some pharmacological effects of vasoactive intestinal polypeptide in human and monkey corpus cavernosum.

    Science.gov (United States)

    Steers, W D; McConnell, J; Benson, G S

    1984-11-01

    Vasoactive intestinal polypeptide is hypothesized to be a nonadrenergic, noncholinergic neurotransmitter important in the physiology of penile erection. To further explore this concept, anatomical localization of vasoactive intestinal polypeptide, in vitro muscle bath studies and in vivo injection experiments were undertaken in the monkey and man. Using immunohistochemical techniques vasoactive intestinal polypeptide was localized at the light microscopic level to nerves within the monkey and human penis. Ultrastructurally, a modified peroxidase-antiperoxidase technique was used to identify large vasoactive intestinal polypeptide-positive vesicles within peptidergic and cholinergic varicosities. In the in vitro muscle bath, the addition of 10(-7) M vasoactive intestinal polypeptide did not alter the baseline tension of strips of monkey and human corpus cavernosum. During contraction produced by norepinephrine stimulation, however, vasoactive intestinal polypeptide (10(-7) M) caused relaxation of the monkey (41 +/- 18 per cent, no. = 8) and human (23 +/- 8 per cent, no. = 5) corpus cavernosum. Intracorporal injection of vasoactive intestinal polypeptide (0.75 X 10(-9) to 3.75 X 10(-9) moles/kg.) had no effect on the monkey penis. Administration of vasoactive intestinal polypeptide (1.25 X 10(-9) to 2.5 X 10(-9) moles/kg.) into the internal iliac artery of the monkey, while having no effect on the flaccid penis, caused detumescence of the erect penis obtained by cavernous nerve stimulation (2-5 V, 40 Hz, 2 msec.). Although vasoactive intestinal polypeptide can be found within the nerves of the penis, its apparent in vitro and in vivo effects raise further questions concerning the role of this peptide in penile erection.

  7. Anatomical Variation of Age-Related Changes in Vertebral Bone Marrow Composition Using Chemical Shift Encoding-Based Water–Fat Magnetic Resonance Imaging

    Directory of Open Access Journals (Sweden)

    Thomas Baum

    2018-04-01

    Full Text Available Assessment of vertebral bone marrow composition has been proposed as imaging biomarker for osteoporosis, hematopoietic, and metabolic disorders. We investigated the anatomical variation of age-related changes of vertebral proton density fat fraction (PDFF using chemical shift encoding-based water–fat magnetic resonance imaging (MRI. 156 healthy subjects were recruited (age range 20–29 years: 12/30 males/females; 30–39: 15/9; 40–49: 4/14; 50–59: 9/27; 60–69: 5/19; 70–79: 4/8. An eight-echo 3D spoiled gradient-echo sequence at 3T MRI was used for chemical shift-encoding based water–fat separation at the lumbar spine. Vertebral bodies of L1–L4 were manually segmented to extract PDFF values at each vertebral level. PDFF averaged over L1–L4 was significantly (p < 0.05 higher in males than females in the twenties (32.0 ± 8.0 vs. 27.2 ± 6.0% and thirties (35.3 ± 6.7 vs. 27.3 ± 6.2%. With increasing age, females showed an accelerated fatty conversion of the bone marrow compared to men with no significant (p > 0.05 mean PDFF differences in the forties (32.4 ± 8.4 vs. 34.5 ± 6.8% and fifties (42.0 ± 6.1 vs. 40.5 ± 9.7%. The accelerated conversion process continued resulting in greater mean PDFF values in females than males in the sixties (40.2 ± 6.9 vs. 48.8 ± 7.7%; p = 0.033 and seventies (43.9 ± 7.6 vs. 50.5 ± 8.2%; p = 0.208, though the latter did not reach statistical significance. Relative age-related PDFF change from the twenties to the seventies increased from 16.7% (L1 to 51.4% (L4 in males and 76.8% (L1 to 85.7% (L4 in females. An accelerated fatty conversion of bone marrow was observed in females with increasing age particularly evident after menopause. Relative age-related PDFF changes showed an anatomical variation with most pronounced changes at lower lumbar vertebral levels in both sexes.

  8. Variation in Location of the Mandibular Foramen/Inferior Alveolar Nerve Complex Given Anatomic Landmarks Using Cone-beam Computed Tomographic Scans.

    Science.gov (United States)

    Blacher, Jonathan; Van DaHuvel, Scott; Parashar, Vijay; Mitchell, John C

    2016-03-01

    The inferior alveolar nerve (IAN) injection is 1 of the most commonly administered and useful injections in the field of dentistry. Practitioners use intraoral anatomic landmarks, which vary greatly among patients. The objective of this study was to assist practitioners by identifying a range of normal variability within certain landmarks used in delivering IAN anesthesia. A total of 203 randomly selected retrospective cone-beam computed tomographic scans were obtained from the Midwestern University Dental Institute cone-beam computed tomographic database. InVivoDental5.0 volumetric imaging software (Anatomage, San Jose, CA) was used to measure 2 important parameters used in locating the mandibular foramen (MF)/IAN complex: (1) the angle from the contralateral premolar contact area to the MF and (2) the distance above the mandibular occlusal plane to the center of the MF. The variation of these measurements was compared with established reference values and statistically analyzed using a 1-sample t test. The angle from the contralateral premolar contact area to the MF for the right and left sides was 42.99° and 42.57°, respectively. The angulations varied significantly from the reference value of 45° (P < .001). The minimum height above the mandibular occlusal plane for the right and left sides was 9.85 mm and 9.81 mm, respectively. The heights varied significantly from the minimum reference value of 6 mm but not the maximum reference value of 10 mm (P < .001). Orienting the syringe barrel at an angulation slightly less than 45° and significantly higher than 6 mm above the mandibular occlusal plane can aid in successfully administering anesthesia to the MF/IAN complex. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  9. Fabrication and variation of the cut-out yield of beef carcasses in Venezuela: anatomical description of the process and equivalency of cut nomenclature to North American counterparts

    Directory of Open Access Journals (Sweden)

    Angela Montero

    2014-06-01

    Full Text Available The typical processes of beef carcass fabrication in Venezuela are anatomically described and the equivalence in cut nomenclature with that of México and United States is provided. Additionally, 910 carcasses were fabricated to assess yield (kg and percentages of carcass weight in products (subprimals, subprimal groups of distinct commercial value (High, Medium, Low and by-products (bone, fat trimmings using mean values ± standard deviation (DE, coefficient of variation (CV and range of values. Once the carcass is ribbed at the 5th intercostal space, subprimals are obtained by deboning and dissecting the muscle masses (saw cutting is seldom used. In terms of yield, the top three (out of 18 individual subprimals were: Solomo Abierto (boneless Chuck Roll, 39.1± 10.88kg; 14.3± 2.84%, Costilla (bone-in Plate, 22kg± 4.15; 8.12± 0.88% and Solomo de Cuerito (boneless Rib and Loin, 21.6± 3.10kg; 8.0± 0.59%. Cutability values for High-Valued and Medium-Valued subprimal groups were 81.5± 10.3kg (30.2± 1.43% and 67.3± 14.57kg (24.8± 3.22%, respectively; the latter showing the highest CV (13.0%. Fat trimmings were the most variable by-product (10.1± 2.84%, CV = 28.0%. This report serves as a reference for future studies and could facilitate the commercial language for trading beef cuts between the countries involved

  10. The effect of steroid-abuse on anatomic reinsertion of ruptured distal biceps brachii tendon.

    Science.gov (United States)

    Pagonis, Thomas; Givissis, Panagiotis; Ditsios, Kostantinos; Pagonis, Athanasios; Petsatodis, Georgios; Christodoulou, Anastasios

    2011-11-01

    There is an increase in the number of anabolic-steroid (AS)-abusing trainees, who suffer from sports injuries, needing reconstruction surgery. Rupture of the distal biceps brachii tendon is a common injury in this group. The study aimed to investigate the effect of AS abuse in the anatomic reconstruction of the ruptured distal biceps brachii tendon along with an immediate range-of-motion postoperative protocol. We conducted an observation study of 17 male athletes suffering from distal biceps tendon ruptures. Six of them reported that they abused AS (group A), whereas the non-users comprised group B (n=11). Both groups were treated with the modified single-incision technique with two suture anchors and an immediate active range-of-motion protocol postoperatively. Follow-up was at 4, 16 and 52 weeks postoperatively, with a final follow-up at 24 months. Follow-up at 4, 16 and 52 weeks postoperatively showed a statistical significance in favour of group A for therapeutic outcomes concerning flexion, supination, pronation, Disabilities of the Arm, Shoulder and Hand (DASH) Disability Symptom Scores, Mayo Elbow Performance Elbow Scores and isometric muscle strength tests for both flexion and supination. Twenty-four months postoperatively, statistical significance in favour of group A was recorded in isometric muscle strength tests for both flexion and supination and also in DASH Disability Symptom Score. The results of our study suggest that there is a correlation between the effect of AS and the quicker and better recuperation and rehabilitation observed in group A. Nonetheless, these results must be interpreted with caution, and further in vivo research is needed to confirm these findings. Copyright © 2011 Elsevier Ltd. All rights reserved.

  11. Effect of hyoscine butylbromide on prostate multiparametric MRI anatomical and functional image quality.

    Science.gov (United States)

    Slough, R A; Caglic, I; Hansen, N L; Patterson, A J; Barrett, T

    2018-02-01

    To evaluate the effect of the spasmolytic agent hyoscine butylbromide (HBB) on the quality of anatomical and functional imaging of the prostate. One hundred and seventy-three patients were included in this retrospective study. Eighty-seven patients received intravenous HBB prior to scanning (HBB group) and 86 patients did not (non-HBB group). Multiparametric (mp) 3 T magnetic resonance imaging (MRI) was performed using a 32-channel body coil. Two radiologists independently evaluated the image quality of T2-weighted imaging (WI), diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) maps, using a five-point Likert scale. DWI was further assessed for distortion and artefact (four-point Likert scale), and T2WI for the presence of motion artefact or blurring. Dynamic contrast-enhanced (DCE) image quality was assessed by recording the number of corrupt contrast curve data points. T2W image quality in the HBB group was significantly higher than in the non-HBB group (3.63±1.11 versus 2.84±0.899); ppoints from the contrast curve (2.47±2.44 versus 3.68±2.64), but this did not reach significance (p=0.052). Administration of HBB significantly improves the image quality of T2WI images. These results provide evidence for the use of HBB in routine patient preparation prior to prostate mpMRI. Copyright © 2017 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  12. The effect of dose reduction on the detection of anatomical structures on panoramic radiographs.

    Science.gov (United States)

    Kaeppler, G; Dietz, K; Reinert, S

    2006-07-01

    The aim was to evaluate the effect of dose reduction on diagnostic accuracy using different screen-film combinations and digital techniques for panoramic radiography. Five observers assessed 201 pairs of panoramic radiographs (a total of 402 panoramic radiographs) taken with the Orthophos Plus (Sirona, Bensheim, Germany), for visualization of 11 anatomical structures on each side, using a 3-point scale -1, 0 and 1. Two radiographs of each patient were taken at two different times (conventional setting and setting with decreased dose, done by increasing tube potential settings or halving tube current). To compare the dose at different tube potential settings dose-length product was measured at the secondary collimator. Films with medium and regular intensifying screens (high and low tube potential settings) and storage phosphor plates (low tube potential setting, tube current setting equivalent to regular intensifying screen and halved) were compared. The five observers made 27 610 assessments. Intrarater agreement was expressed by Cohen's kappa coefficient. The results demonstrated an equivalence of regular screens (low tube potential setting) and medium screens (high and low tube potential settings). A significant difference existed between medium screens (low tube potential setting, mean score 0.92) and the group of regular film-screen combinations at high tube potential settings (mean score 0.89) and between all film-screen combinations and the digital system irrespective of exposure (mean score below 0.82). There were no significant differences between medium and regular screens (mean score 0.88 to 0.92) for assessment of the periodontal ligament space, but there was a significant difference compared with the digital system (mean score below 0.76). The kappa coefficient for intrarater agreement was moderate (0.55). New regular intensifying screens can replace medium screens at low tube potential settings. Digital panoramic radiographs should be taken at low

  13. Effects of air pollution on morphological and anatomical characteristics of Pinus Eldarica Wood

    Science.gov (United States)

    Vahidreza Safdari; Moinuddin Ahmed; Margaret S. Devall; Vilma Bayramzadeh

    2012-01-01

    Air pollution, including automobile exhaust pollution, can affect anatomical and morphological characteristics of wood. In order to evaluate this subject, the Pinus eldarica trees of Chitgar Park in Tehran, which extends from a crowded highway in the south (polluted site) to the semi polluted midsection and to Alborz Mountain in the north (unpolluted...

  14. Using ring width correlations to study the effects of plantation density on wood density and anatomical properties of red pine (Pinus resinosa Ait.)

    Science.gov (United States)

    J. Y. Zhu; C. T. Scott; K. L. Scallon; G. C. Myers

    2006-01-01

    This study demonstrated that average ring width (or average annual radial growth rate) is a reliable parameter to quantify the effects of tree plantation ndensity (growth suppression) on wood density and tracheid anatomical properties. The average ring width successfully correlated wood density and tracheid anatomical properties of red pines (Pinus resinosa Ait.) from...

  15. 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.

  16. Variation in Incentive Effects across Neighbourhoods

    Directory of Open Access Journals (Sweden)

    Mark J Hanly

    2014-03-01

    Full Text Available Small monetary incentives increase survey cooperation rates, however evidence suggests that the appeal of incentives may vary across sample subgroups. Fieldwork budgets can be most effectively distributed by targeting those subgroups where incentives will have the strongest appeal. We examine data from a randomised experiment implemented in the pilot phase of the Irish Longitudinal Study of Ageing, which randomly assigned households to receive a higher (€25 or lower (€10 incentive amount. Using a random effects logistic regression model, we observe a variable effect of the higher incentive across geographic neighbourhoods. The higher incentive has the largest impact in neighbourhoods where baseline cooperation is low, as predicted by Leverage-Saliency theory. Auxiliary neighbourhood-level variables are linked to the sample frame to explore this variation further, however none of these moderate the incentive effect, suggesting that richer information is needed to identify sample subgroups where incentive budgets should be directed.

  17. Effect of Cuscuta campestris parasitism on the physiological and anatomical changes in untreated and herbicide-treated sugar beet.

    Science.gov (United States)

    Saric-Krsmanovic, Marija M; Bozic, Dragana M; Radivojevic, Ljiljana M; Umiljendic, Jelena S Gajic; Vrbnicanin, Sava P

    2017-11-02

    The effects of field dodder on physiological and anatomical processes in untreated sugar beet plants and the effects of propyzamide on field dodder were examined under controlled conditions. The experiment included the following variants: N-noninfested sugar beet plants (control); I - infested sugar beet plants (untreated), and infested plants treated with propyzamide (1500 g a.i. ha -1 (T 1 ) and 2000 g a.i. ha -1 (T 2 )). The following parameters were checked: physiological-pigment contents (chlorophyll a, chlorophyll b, total carotenoids); anatomical -leaf parameters: thickness of epidermis, parenchyma and spongy tissue, mesophyll and underside leaf epidermis, and diameter of bundle sheath cells; petiole parameters: diameter of tracheid, petiole hydraulic conductance, xylem surface, phloem cell diameter and phloem area in sugar beet plants. A conventional paraffin wax method was used to prepare the samples for microscopy. Pigment contents were measured spectrophotometrically after methanol extraction. All parameters were measured: prior to herbicide application (0 assessment), then 7, 14, 21, 28 and 35 days after application (DAA). Field dodder was found to affect the pigment contents in untreated sugar beet plants, causing significant reductions. Conversely, reduction in the treated plants decreased 27% to 4% for chlorophyll a, from 21% to 5% for chlorophyll b, and from 28% to 5% for carotenoids (T 1 ). Also, in treatment T 2, reduction decreased in infested and treated plants from 19% to 2% for chlorophyll a, from 21% to 2% for chlorophyll b, from 23% to 3% for carotenoids and stimulation of 1% and 2% was observed 28 and 35 DAA, respectively. Plants infested (untreated) by field dodder had lower values of most anatomical parameters, compared to noninfested plants. The measured anatomical parameters of sugar beet leaves and petiole had significantly higher values in noninfested plants and plants treated with propyzamide than in untreated plants. Also, the

  18. Effects of two surface finishes on the color of cemented and colored anatomic-contour zirconia crowns.

    Science.gov (United States)

    Lee, Wei-Fang; Feng, Sheng-Wei; Lu, Yi-Jie; Wu, Hsin-Jui; Peng, Pei-Wen

    2016-08-01

    The esthetic appearance of anatomic-contour zirconia restorations is influenced by the shade of the coloring liquid and the optical properties of the luting cements. However, few studies are available on the effects of surface-finishing methods and luting cements on colored anatomic-contour zirconia restorations. The purpose of this in vitro study was to investigate the effects of surface finishing methods on the color distribution of colored anatomic-contour zirconia crowns before and after being cemented onto abutments. Implant-supported anatomic-contour zirconia premolar crowns were fabricated and immersed in A3-coloring liquid for 30 seconds. The colored zirconia crowns were separated into 3 groups according to the method of surface treatment: no treatment (N), polishing (P), and glazing (G). The zirconia crowns without coloring liquid application served as the control group. CIELab color coordinates were obtained, and color differences (ΔE) between shaded crowns were calculated with a spectrophotometer. The color stability of the crown before and after cement application was also investigated. Before cement application, the mean color difference between groups N and P was 2.85 ΔE units, whereas the mean ΔE value between groups N and G was 3.27. Mean ΔE values with and without cement application among groups ranged from 2.75 to 3.45 ΔE units. The color appearance of the colored zirconia crowns was strongly influenced by the surface-finishing methods and luting cement application. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  19. Effect of anatomical variability in brain on transcranial magnetic stimulation treatment

    Science.gov (United States)

    Syeda, F.; Magsood, H.; Lee, E. G.; El-Gendy, A. A.; Jiles, D. C.; Hadimani, R. L.

    2017-05-01

    Transcranial Magnetic Stimulation is a non-invasive clinical therapy used to treat depression and migraine, and shows further promise as treatment for Parkinson's disease, Alzheimer's disease, and other neurological disorders. However, it is yet unclear as to how anatomical differences may affect stimulation from this treatment. We use finite element analysis to model and analyze the results of Transcranial Magnetic Stimulation in various head models. A number of heterogeneous head models have been developed using MRI data of real patients, including healthy individuals as well as patients of Parkinson's disease. Simulations of Transcranial Magnetic Stimulation performed on 22 anatomically different models highlight the differences in induced stimulation. A standard Figure of 8 coil is used with frequency 2.5 kHz, placed 5 mm above the head. We compare cortical stimulation, volume of brain tissue stimulated, specificity, and maximum E-field induced in the brain for models ranging from ages 20 to 60. Results show that stimulation varies drastically between patients of the same age and health status depending upon brain-scalp distance, which is not necessarily a linear progression with age.

  20. Bidirectional anatomical effects in a mistletoe-host relationship: Psittacanthus schiedeanus mistletoe and its hosts Liquidambar styraciflua and Quercus germana.

    Science.gov (United States)

    Cocoletzi, Eliezer; Angeles, Guillermo; Ceccantini, Gregório; Patrón, Araceli; Ornelas, Juan Francisco

    2016-06-01

    During the interactions between a parasitic plant and its host, the parasite affects its host morphologically, anatomically, and physiologically, yet there has been little focus on the effect of hosts on the parasite. Here, the functional interactions between the hemiparasitic mistletoe Psittacanthus schiedeanus and its hosts Liquidambar styraciflua and Quercus germana were interpreted based on the anatomical features of the vascular tissues. Using standard techniques for light and transmission electron microscopy, we studied the effects of P. schiedeanus on the phloem anatomy of Liquidambar styraciflua and Quercus germana and vice versa. The phloem of P. schiedeanus has larger sieve elements, companion cells, and sieve plate areas when it is parasitizing L. styraciflua than Q. germana; however, the parasite produces systemic effects on the phloem of its hosts, reducing the size of phloem in L. styraciflua but increasing it in Q. germana. Those seem to be the bidirectional effects. No direct connections between the secondary phloem of the parasite and that of its hosts were observed. Parenchymatic cells of L. styraciflua in contact with connective parenchyma cells of the parasite develop half-plasmodesmata, while those of Q. germana do not. The bidirectional effects between the parasite and its hosts comprise modifications in secondary phloem that are potentially affected by the phenology of its hosts, a combination of hormonal agents such as auxins, and the symplasmic or apoplasmic pathway for solutes import. © 2016 Botanical Society of America.

  1. Effect of salinity on biomass yield and physiological and stem-root anatomical characteristics of purslane (Portulaca oleracea L.) accessions.

    Science.gov (United States)

    Alam, Md Amirul; Juraimi, Abdul Shukor; Rafii, M Y; Abdul Hamid, Azizah

    2015-01-01

    13 selected purslane accessions were subjected to five salinity levels 0, 8, 16, 24, and 32 dS m(-1). Salinity effect was evaluated on the basis of biomass yield reduction, physiological attributes, and stem-root anatomical changes. Aggravated salinity stress caused significant (P < 0.05) reduction in all measured parameters and the highest salinity showed more detrimental effect compared to control as well as lower salinity levels. The fresh and dry matter production was found to increase in Ac1, Ac9, and Ac13 from lower to higher salinity levels but others were badly affected. Considering salinity effect on purslane physiology, increase in chlorophyll content was seen in Ac2, Ac4, Ac6, and Ac8 at 16 dS m(-1) salinity, whereas Ac4, Ac9, and Ac12 showed increased photosynthesis at the same salinity levels compared to control. Anatomically, stem cortical tissues of Ac5, Ac9, and Ac12 were unaffected at control and 8 dS m(-1) salinity but root cortical tissues did not show any significant damage except a bit enlargement in Ac12 and Ac13. A dendrogram was constructed by UPGMA based on biomass yield and physiological traits where all 13 accessions were grouped into 5 clusters proving greater diversity among them. The 3-dimensional principal component analysis (PCA) has also confirmed the output of grouping from cluster analysis. Overall, salinity stressed among all 13 purslane accessions considering biomass production, physiological growth, and anatomical development Ac9 was the best salt-tolerant purslane accession and Ac13 was the most affected accession.

  2. Effect of patient size, anatomical location and modulation strength on dose delivered and image-quality on CT examination

    International Nuclear Information System (INIS)

    Greffier, Joel; Larbi, Ahmed; Macri, Francesco; Beregi, Jean-Paul; Pereira, Fabricio

    2017-01-01

    To study the effect of patient size, anatomical location and modulation strength (MS) on image-quality and delivered dose of CT scans acquired with automatic-exposure control system (AEC). Four anthropomorphic phantoms (three paediatric and one thin adult) were studied, and normal and obese adults were simulated by placing bolus plates around the adult phantom. Thorax and abdomen pelvis CT were performed using an AEC system equipped with five possible MS. Modulated tube current (mAs mod ) was compared to Reference mAs and image-noise was assessed. Effective-mAs were lower than Reference-mAs for all but the obese phantom. However, reversal points were estimated for an effective diameter of 27.8 cm in thorax and 26.9 cm in abdomen pelvis scans, beyond which the patterns of MS were inverted. mAs mod were dependent on attenuation differences among distinct anatomical location. Finally, dose delivered was associated to the mAs mod and patient s size, with both affecting image-quality. (authors)

  3. Effects of temperature variation on MOSFET dosimetry

    International Nuclear Information System (INIS)

    Cheung Tsang; Butson, Martin J; Yu, Peter K N

    2004-01-01

    This note investigates temperature effects on dosimetry using a metal oxide semiconductor field effect transistor (MOSFET) for radiotherapy x-ray treatment. This was performed by analysing the dose response and threshold voltage outputs for MOSFET dosimeters as a function of ambient temperature. Results have shown that the clinical semiconductor dosimetry system (CSDS) MOSFET provides stable dose measurements with temperatures varying from 15 deg. C up to 40 deg. C. Thus standard irradiations performed at room temperature can be directly compared to in vivo dose assessments performed at near body temperature without a temperature correction function. The MOSFET dosimeter threshold voltage varies with temperature and this level is dependent on the dose history of the MOSFET dosimeter. However, the variation can be accounted for in the measurement method. For accurate dosimetry, the detector should be placed for approximately 60 s on a patient to allow thermal equilibrium before measurements are taken with the final reading performed whilst still attached to the patient or conversely left for approximately 120 s after removal from the patient if initial readout was measured at room temperature to allow temperature equilibrium to be established. (note)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-07-01

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

  5. 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

  6. Effects of an oil spill on the leaf anatomical characteristics of a beach plant (Terminalia catappa L.).

    Science.gov (United States)

    Punwong, Paramita; Juprasong, Yotin; Traiperm, Paweena

    2017-09-01

    This study investigated the short-term impacts of an oil spill on the leaf anatomical structures of Terminalia catappa L. from crude oil leakage in Rayong province, Thailand, in 2013. Approximately 3 weeks after the oil spill, leaves of T. catappa were collected along the coastline of Rayong from one affected site, five adjacent sites, and a control site. Slides of the leaf epidermis were prepared by the peeling method, while leaf and petiole transverse sections were prepared by paraffin embedding. Cell walls of adaxial epidermal cell on leaves in the affected site were straight instead of the jigsaw shape found in leaves from the adjacent and control sites. In addition, the stomatal index of the abaxial leaf surface was significantly lower in the affected site. Leaf and petiole transverse sections collected from the affected site showed increased cuticle thickness, epidermal cell diameter on both sides, and palisade mesophyll thickness; in contrast, vessel diameter and spongy mesophyll thickness were reduced. These significant changes in the leaf anatomy of T. catappa correspond with previous research and demonstrate the negative effects of oil spill pollution on plants. The anatomical changes of T. catappa in response to crude oil pollution are discussed as a possible indicator of pollution and may be used in monitoring crude oil pollution.

  7. On the new anatomical nomenclature.

    Science.gov (United States)

    Marecková, E; Simon, F; Cervený, L

    2001-05-01

    The present paper is concerned with the linguistic aspect of the new anatomical nomenclature (Terminologia Anatomica 1998). Orthographic, morphological, syntactic, lexical, and terminological comments are presented. In the authors' opinion, shortcomings might have been effectively avoided by cooperation with linguists.

  8. Molecular alterations induced by a high-fat high-fiber diet in porcine adipose tissues: variations according to the anatomical fat location.

    Science.gov (United States)

    Gondret, Florence; Vincent, Annie; Houée-Bigot, Magalie; Siegel, Anne; Lagarrigue, Sandrine; Louveau, Isabelle; Causeur, David

    2016-02-18

    Changing the energy and nutrient source for growing animals may be an effective way of limiting adipose tissue expansion, a response which may depend on the genetic background of the animals. This study aims to describe the transcriptional modulations present in the adipose tissues of two pig lines divergently selected for residual feed intake which were either fed a high-fat high-fiber (HF) diet or an isocaloric low-fat high-starch diet (LF). Transcriptomic analysis using a porcine microarray was performed on 48 pigs (n = 12 per diet and per line) in both perirenal (PRAT) and subcutaneous (SCAT) adipose tissues. There was no interaction between diet and line on either adiposity or transcriptional profiles, so that the diet effect was inferred independently of the line. Irrespective of line, the relative weights of the two fat depots were lower in HF pigs than in LF pigs after 58 days on dietary treatment. In the two adipose tissues, the most apparent effect of the HF diet was the down-regulation of several genes associated with the ubiquitin-proteasome system, which therefore may be associated with dietary-induced modulations in genes acting in apoptotic and cell cycle regulatory pathways. Genes involved in glucose metabolic processes were also down-regulated by the HF diet, with no significant variation or decreased expression of important lipid-related genes such as the low-density lipoprotein receptor and leptin in the two fat pads. The master regulators of glucose and fatty acid homeostasis SREBF1 and MLXIPL, and peroxisome proliferator-activated receptor (PPAR)δ and its heterodimeric partner RXRA were down-regulated by the HF diet. PPARγ which has pleiotropic functions including lipid metabolism and adipocyte differentiation, was however up-regulated by this diet in PRAT and SCAT. Dietary-related modulations in the expression of genes associated with immunity and inflammation were mainly revealed in PRAT. A high-fat high-fiber diet depressed glucose and

  9. 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.

  10. [EFFECTIVENESS OF ANATOMIC FEMORAL COMPONENT PROSTHESIS FOR SEVERE DEVELOPMENTAL DYSPLASIA OF THE HIP IN TOTAL HIP ARTHROPLASTY].

    Science.gov (United States)

    An, Xiao; Dong, Jiyuan; Gong, Ke; Zhang, Qi; Li, Xiang; Song, Wei

    2015-04-01

    To evaluate the effectiveness of anatomic femoral component prosthesis for severe development dysplasia of the hip (DDH) in total hip arthroplasty (THA). Between September 2009 and September 2013, 48 patients (51 hips) with severe DDH underwent THA with cementless anatomic femoral component prosthesis. There were 5 males (5 hips) and 43 females (46 hips) with an average age of 51 years (range, 28-67 years). The left hip was involved in 25 cases, the right hip in 20 cases, and bilateral hips in 3 cases. There were 39 cases (44 hips) of Crowe type III and 9 cases (7 hips) of Crowe type IV. The visual analogue scale (VAS) score was 5.72 +/- 1.84, and Harris score was 41.66 +/- 4.87 at preoperation. All patients had leg discrepancy with a length difference of (4.31 +/- 0.84) cm. The duration of surgery was 59-110 minutes (mean, 78.6 minutes), and the hospitalization days were 6-20 days (mean, 12.3 days). All patients obtained primary healing of incision without wound related complications of swelling, effusion, and infection. Two patients were found to have intramuscular venous thrombosis. All patients were followed up 10-54 months (mean, 29 months). Limp was observed at the early stage after operation in 9 patients and disappeared after 1 year, the other patients had normal gait. The VAS score 1.46?0.47, Harris score 88.66 +/- 3.48, and the leg length difference (1.15 +/- 0.33) cm at last follow-up all showed significant differences when compared with the preoperative values (Phip joint function and limb discrepancy. Short-term effectiveness was satisfactory, but the long-term effectiveness should still be observed in future.

  11. Poster - Thurs Eve-17: Stand alone software for deforming delivered dose distributions to account for daily anatomical variations in prostate patients treated on the TomoTherapy Hi-Art II system.

    Science.gov (United States)

    Rivest, R; Riauka, T; Murtha, A; Fallone, G

    2008-07-01

    The acquisition of daily megavoltage (MV)-CT images provides an invaluable tool in the delivery of adaptive radiotherapy (ART) on the TomoTherapy Hi-ART II system. Using TomoTherapy's Planned Adaptive software, delivery sinograms can be applied to pre-treatment MVCT images to generate daily delivered dose distributions, allowing for the potential comparison of planned and delivered doses. However, daily patient anatomical variations complicate the task and accurate comparison requires that daily doses be evaluated in the same references frame as the planned dose. Each anatomical point in daily MVCT images must be mapped to its corresponding point in the patient planning CT and that deformation map must be applied to the daily dose distribution. Stand alone software has been developed for the comparison of planned and delivered doses for TomoTherapy prostate patients. Software inputs are the planning CT, planning structure data, planned dose distribution, daily MVCT and delivered dose distribution. The software uses an in-house developed automatic voxel-based deformable registration algorithm designed and optimized specifically for the registration of prostate CT images to achieve anatomical correspondence between MVCT and planning images. The resultant deformation map is applied to the daily dose distribution and the software outputs the deformed daily dose distribution in the planning CT's reference frame, as well as a delivered DVH for each of the planning CT's ROI. The software allows for a number of potential research opportunities, in particular, the calculation of the cumulative dose delivered over the course of treatment for prostate patients treated on the Hi-Art II system. © 2008 American Association of Physicists in Medicine.

  12. Analyses of anatomical relationship between mandibular third molar roots and variations in lingual undercut of mandible using cone-beam computed tomography

    Directory of Open Access Journals (Sweden)

    Sertac Aktop

    2017-09-01

    Conclusion: The narrow angulation of the lingual balcony region and the relationship between roots and lingual soft tissues should be noted to avoid undesirable complication of displacement of a tooth or fragment into sublingual, submandibular, and pterygomandibular spaces. There was no relation in the floor of the mouth between the position of the impacted third molar roots and different lingual undercut angulation variations.

  13. Genes and gene clusters related to genotype and drought-induced variation in saccharification potential, lignin content and wood anatomical traits in Populus nigra

    NARCIS (Netherlands)

    Wildhagen, Henning; Paul, Shanty; Allwright, Mike; Smith, Hazel K.; Malinowska, Marta; Schnabel, S.K.; Caldas Paulo, M.J.; Cattonaro, Federica; Vendramin, Vera; Scalabrin, Simone; Eeuwijk, van F.A.; Keurentjes, J.J.B.

    2017-01-01

    Wood is a renewable resource that can be employed for the production of second generation biofuels by enzymatic saccharification and subsequent fermentation. Knowledge on how the saccharification potential is affected by genotype-related variation of wood traits and drought is scarce. Here, we used

  14. Passive vs. active virtual reality learning: the effects on short- and long-term memory of anatomical structures.

    Science.gov (United States)

    Phelps, Andrew; Fritchle, Alicia; Hoffman, Helene

    2004-01-01

    This pilot study compares the differences in learning outcomes when students are presented with either an active (student-centered) or passive (teacher-centered) virtual reality-based anatomy lesson. The "active" lesson used UCSD's Anatomic VisualizeR and enabled students to interact with 3D models and control presentation of learning materials. The "passive" lesson used a digital recording of an anatomical expert's tour of the same VR lesson played back as a QuickTime movie. Subsequent examination of the recall and retention of the studied anatomic objects were comparable in both groups. Issues underlying these results are discussed.

  15. 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)

  16. [Winging effect in interatrial defect after transseptal mitral valvuloplasty: an anatomical study].

    Science.gov (United States)

    Martuscelli, E; Avella, A; Berni, A; Melis, M; Soda, G; Ferraironi, A; Nigri, A; Reale, A

    1990-04-01

    In the balloon catheters the redundancy of the deflated balloon produces 2 or 3 sort of thin wings. The presence of wings can reduce the catheter "pushability" or, in certain conditions, can determine tissue lesion (winging effect). Simulating a transeptal valvuloplasty of the mitral valve by technique of the 2 balloon in human fresh heart, we studied the winging effect over the interatrial septum in 12 hearts; in the first 6 the atrial septum was dilated with a 6 mm balloon (Group A), in the second 6 the atrial septum was dilated with a 10 mm balloon (Group B). The procedure was completed introducing consecutively 2 bigger balloons (15 + 20 mm). We suppose that the winging effect of the 2 bigger balloons (15 + 20 mm) could counter balance the theoretical advantage of a small balloon (6 mm). The atrial septal defect (ASD) after septal dilatation was 5.0 +/- 0.59 mm x 1.56 +/- 0.25 mm (long axis x short axis) in Group A and 6.53 +/- 0.35 x 2.16 +/- 0.39 mm in Group B (p less than 0.01). The final ASD (after introducing the 2 bigger balloons) was 7.04 +/- 1.06 x 2.36 +/- 0.57 mm in Group A and 7.03 +/- 0.18 x 2.16 +/- 0.32 mm in Group B (NS). Our data show that the winging effect can determine biological negative effects.

  17. Cardiac resynchronisation therapy in paediatric and congenital heart disease: differential effects in various anatomical and functional substrates

    NARCIS (Netherlands)

    Janousek, J.; Gebauer, R. A.; Abdul-Khaliq, H.; Turner, M.; Kornyei, L.; Grollmuss, O.; Rosenthal, E.; Villain, E.; Früh, A.; Paul, T.; Blom, N. A.; Happonen, J.-M.; Bauersfeld, U.; Jacobsen, J. R.; van den Heuvel, F.; Delhaas, T.; Papagiannis, J.; Trigo, C.

    2009-01-01

    BACKGROUND: Cardiac resynchronisation therapy (CRT) is increasingly used in children in a variety of anatomical and pathophysiological conditions, but published data are scarce. OBJECTIVE: To record current practice and results of CRT in paediatric and congenital heart disease. DESIGN: Retrospective

  18. Cardiac resynchronisation therapy in paediatric and congenital heart disease : differential effects in various anatomical and functional substrates

    NARCIS (Netherlands)

    Janousek, J.; Gebauer, R. A.; Abdul-Khaliq, H.; Turner, M.; Kornyei, L.; Grollmuss, O.; Rosenthal, E.; Villain, E.; Frueh, A.; Paul, T.; Blom, N. A.; Happonen, J-M; Bauersfeld, U.; Jacobsen, J. R.; van den Heuvel, F.; Delhaas, T.; Papagiannis, J.; Trigo, C.

    2009-01-01

    Background: Cardiac resynchronisation therapy (CRT) is increasingly used in children in a variety of anatomical and pathophysiological conditions, but published data are scarce. Objective: To record current practice and results of CRT in paediatric and congenital heart disease. Design: Retrospective

  19. Gamma radiation effect on the anatomical structure of soybean (Glycine max. Merr)

    International Nuclear Information System (INIS)

    Bhikuningputra, W.

    1976-01-01

    Gamma radiation effects on soybean plant (Glycine max. Merr) have been studied by using radiation doses of 0, 20, 25, 30, and 35 Krad. Investigation is carried out after each treatment. It proves that each treatment causes different morphological changes on leaves, stems, roots, and fibres of the treated plants. (SMN)

  20. Jensen's Inequality Predicts Effects of Environmental Variation

    Science.gov (United States)

    Jonathan J. Ruel; Matthew P. Ayres

    1999-01-01

    Many biologists now recognize that environmental variance can exert important effects on patterns and processes in nature that are independent of average conditions. Jenson's inequality is a mathematical proof that is seldom mentioned in the ecological literature but which provides a powerful tool for predicting some direct effects of environmental variance in...

  1. Effect of Lean method implementation in the histopathology section of an anatomical pathology laboratory.

    Science.gov (United States)

    Raab, S S; Grzybicki, D M; Condel, J L; Stewart, W R; Turcsanyi, B D; Mahood, L K; Becich, M J

    2008-11-01

    In the USA, the lack of processes standardisation in histopathology laboratories leads to less than optimal quality, errors, inefficiency and increased costs. The effectiveness of large-scale quality improvement initiatives has been evaluated rarely. To measure the effect of implementation of a Lean quality improvement process on the efficiency and quality of a histopathology laboratory section. A non-concurrent interventional cohort study from 1 January 2003 to 31 December 2006 was performed, and the Lean process was implemented on 1 January 2004. Also compared was the productivity of the Lean histopathology section to a sister histopathology section that did not implement Lean processes. Pre- and post-Lean specimen turnaround time and productivity ratios (work units/full time equivalents) were measured. For 200 Lean interventions, a 5-part Likert scale was used to assess the impact on error, success and complexity. In the Lean laboratory, the mean monthly productivity ratio increased from 3439 to 4074 work units/full time equivalents (phistopathology section specimen turnaround time decreased from 9.7 to 9.0 h (p = 0.01). The Lean histopathology section had a higher productivity ratio compared with a sister histopathology section (1598 work units/full time equivalents, phistopathology section.

  2. Variational methods and effective actions in string models

    International Nuclear Information System (INIS)

    Dereli, T.; Tucker, R.W.

    1987-01-01

    Effective actions motivated by zero-order and first-order actions are examined. Particular attention is devoted to a variational procedure that is consistent with the structure equations involving the Lorentz connection. Attention is drawn to subtleties that can arise in varying higher-order actions and an efficient procedure developed to handle these cases using the calculus of forms. The effect of constrained variations on the field equations is discussed. (author)

  3. [Effective anatomic structures of ultrasound-guide acupoint embedding therapy for cervical spondylosis].

    Science.gov (United States)

    Sun, Wenshan; Chu, Ningning; Ma, Yilei; Wang, Yumin; Wang, Hong; Jiang, Guofang

    2015-10-01

    To explore the relationship between the therapeutic effect of minimally invasive embedding therapy and the implanted depth for cervical spondylosis. Ninety patients of cervical spondylosis of nerve root type were randomized into a shallow-layer embedding group (subcutaneous layer), a middle-layer embedding group (semispinalis capitis muscle layer) and a deep-layer embedding group (multifidus muscle layer), 30 cases in each one. Jiaji (EX-B 2) of C5 and C6 on the affected side and Dazhui (GV 14) were selected. Under the guide of ultrasound, the catgut was implanted to the corresponding tissue layers. The treatment was given once a week, continuously for 3 weeks in the three groups. The symptoms and physical signs were observed before and after treatment. The pain rating index (PRI), visual analogue scale (VAS) and present pain index (PPI) were assessed. The neck disability index (NDI) was compared. The score of symptoms and function after treatment was increased apparently in the deep-layer embedding group (P spondylosis of nerve root type, the efficacy is different apparently in terms of the implantation depth. The deep-layer implantation, meaning to the multifidus muscle layer is more conductive to the treatment of cervical spondylosis.

  4. The effect of near-peer tutoring on medical students' performance in anatomical and physiological sciences.

    Science.gov (United States)

    Morgan, Katrina M; Northey, Emily E; Khalil, Mohammed K

    2017-10-01

    Healthcare professional schools across the world are implementing near-peer tutoring (NPT) programs owing to numerous benefits to both tutors and tutees. This study determined whether higher attendance at NPT sessions led to improvements in course grades for high and low performing students. Fourth-year medical students used the USMLE Step 1 question format to tutor first-year medical students during the second half of the Structure and Function (SF) module, i.e., SF2. Attendance was recorded and students were accordingly divided into three groups: high, moderate, and low-no attendance. Students' performances in SF1 and SF2 were compared using Student's t-test. Differences among the three groups were analyzed using ANOVA and Scheffé post hoc test (Ptutors highly. They also agreed that NPT prepared them for course exams and Step 1, but did not reduce anxiety and stress about Step 1. The positive effect of the NPT program resulted in its expansion to include all first-year modules. Clin. Anat. 30:922-928, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  5. Anatomic Changes Caused by Endoscopic Endonasal Transsphenoidal Surgery and Their Effects on Nasal Functions.

    Science.gov (United States)

    Kim, Do Hyun; Hong, Yong-Kil; Jeun, Sin-Soo; Park, Yong Jin; Kim, Soo Whan; Cho, Jin Hee; Kim, Boo Young; Han, Sungwoo; Jung, Young Hoon; Lee, Yong Joo; Kim, Sung Won

    2016-06-01

    We evaluated postoperative changes in nasal cavity dimensions and their effects on nasal functions and symptoms. Case series with chart review. Tertiary referral center. We studied patients who underwent binostril, 4-hand endoscopic endonasal transsphenoidal approach surgery with the bilateral modified nasoseptal rescue flap technique. Pre- and postoperative paranasal computed tomography scans were used to assess nasal cavity dimensional changes at 4 levels. We also performed several pre- and postoperative tests, including the Connecticut Chemosensory Clinical Research Center test and the Cross-Cultural Smell Identification Test (n = 119) to evaluate olfactory functions. Also, the Nasal Obstruction Symptoms Evaluation, the Sino-Nasal Outcome Test-20, and a visual analog scale were used (n = 157) to record subjective symptoms. We compared these data with the pre- and postoperative nasal cavity dimensions. Two-dimensional objective increases in nasal passage dimensions were evident postoperatively (all cross-sectional areas, P Cultural Smell Identification Test (all cross-sectional areas, P ≥ .05). Endoscopic endonasal transsphenoidal approach surgery altered the patients' nasal anatomy, but the changes in nasal cavity dimensions did not affect nasal functions and symptoms. These results will help surgeons to appropriately expose the surgical field during endoscopic endonasal transsphenoidal approach surgery. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2016.

  6. RARE TRIPLE ANATOMICAL VARIATION OF THE CEREBRAL ARTERIAL CIRCLE; Rara triple variación del círculo arterial cerebral.

    Directory of Open Access Journals (Sweden)

    Joaquín García Pisón

    2017-04-01

    Full Text Available Se reporta la rara asociación de un aneurisma de arteria trigeminal persistente lateral derecha (Tipo II de Saltzman, aplasia del segmento pre-comunicante de ambas arterias cerebrales posteriores y la presencia de arterias cerebrales posteriores fetales en forma bilateral, en una mujer de 64 años que consultó de diplopía y parálisis del nervio abducens derecho, probablemente debida a compresión del nervio en el espacio latero-celar. Se realizó con éxito la embolización endovascular con coils, sin complicaciones inmediatas. Los hallazgos de CT, RM y angiografía son presentados. Aunque cada una de estas variaciones son infrecuentes en forma individual, la combinación de las mismas no ha sido reportada en la literatura hasta nuestro conocimiento, siendo de enorme importancia en el manejo diagnóstico y terapéutico de pacientes con stroke de mecanismo embolico, así como para la planificación de procedimientos endovasculares diagnósticos y terapéuticos. We report the rare association of an aneurysm of a lateral right persistent trigeminal artery (Saltzman type II, bilateral aplasia of the pre-communicating segment of both posterior cerebral arteries and bilateral fetal posterior cerebral arteries, in a 64 years old woman who suffered from progressive diplopia and right abducens nerve palsy, most likely due to nerve compression in the latero-cellar space. Successful endovascular coils embolization of the aneurysm was performed, with no immediate complications. CT, MR and angiographic findings are presented. Although infrequent as single variations, the association of these three arterial variations has not been reported in literature to our knowledge, having special importance in the diagnostic workup and therapeutic procedures in a patient with an embolic stroke, as well as in the planification of intracranial endovascular diagnostic and therapeutic procedures.

  7. 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.

  8. 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

  9. 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.

  10. 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...

  11. 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.

  12. The superior mesenteric artery and the variations of the colic patterns. A new anatomical and radiological classification of the colic arteries.

    Science.gov (United States)

    Gamo, E; Jiménez, C; Pallares, E; Simón, C; Valderrama, F; Sañudo, J R; Arrazola, J

    2016-07-01

    is responsible of major variations.

  13. 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…

  14. Effects of the Variation in Brain Tissue Mechanical Properties on the Intracranial Response of a 6-Year-Old Child

    Directory of Open Access Journals (Sweden)

    Shihai Cui

    2015-01-01

    Full Text Available Brain tissue mechanical properties are of importance to investigate child head injury using finite element (FE method. However, these properties used in child head FE model normally vary in a large range in published literatures because of the insufficient child cadaver experiments. In this work, a head FE model with detailed anatomical structures is developed from the computed tomography (CT data of a 6-year-old healthy child head. The effects of brain tissue mechanical properties on traumatic brain response are also analyzed by reconstruction of a head impact on engine hood according to Euro-NCAP testing regulation using FE method. The result showed that the variations of brain tissue mechanical parameters in linear viscoelastic constitutive model had different influences on the intracranial response. Furthermore, the opposite trend was obtained in the predicted shear stress and shear strain of brain tissues caused by the variations of mentioned parameters.

  15. Effects of Remnant Tissue Preservation on Clinical and Arthroscopic Results After Anatomic Double-Bundle Anterior Cruciate Ligament Reconstruction.

    Science.gov (United States)

    Kondo, Eiji; Yasuda, Kazunori; Onodera, Jun; Kawaguchi, Yasuyuki; Kitamura, Nobuto

    2015-08-01

    Clinical utility of remnant tissue preservation after single-bundle anterior cruciate ligament (ACL) reconstruction has not been established. In addition, no studies have evaluated the clinical utility of remnant preservation after anatomic double-bundle ACL reconstruction. The study hypotheses were as follows: (1) Subjective and functional clinical results may be comparable between anatomic double-bundle reconstructions that preserve the remnant tissue and those that resect the remnant tissue, (2) postoperative knee stability and the second-look arthroscopic evaluation may be significantly more favorable with the remnant-preserving reconstruction, and (3) the degree of the initial graft coverage may significantly affect postoperative knee stability. Cohort study; Level of evidence, 2. A total of 179 patients underwent anatomic double-bundle ACL reconstruction. Based on the Crain classification of ACL remnant tissue, 81 patients underwent the remnant-preserving procedure (group P) and the remaining 98 patients underwent the remnant-resecting procedure (group R). There were no differences between the 2 groups concerning all background factors, including preoperative knee instability and intraoperative tunnel positions. The patients were followed for 2 years or more. The subjective and functional clinical results were comparable between the 2 reconstruction procedures. Side-to-side anterior laxity was significantly less (P = .0277) in group P (0.9 mm) than in group R (1.5 mm). The pivot-shift test was negative in 89% of group P and 78% of group R patients; the result for group R was significantly lower (P = .0460). In the arthroscopic observations, results for group P were significantly better than for group R concerning postoperative laceration and fibrous tissue coverage of the grafts (P = .0479). Remnant preservation in anatomic double-bundle ACL reconstruction did not significantly improve subjective and functional results in the short-term evaluation, but it

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

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Chemical Sciences; Volume 124; Issue 1. Variation of kinetic isotope ... 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 ...

  17. Effects of seasonal variation and tidal regimes on macrobenthic ...

    African Journals Online (AJOL)

    An assessment of the effects of seasonal variation and tidal regimes on the distribution and density of macrobenthic invertebrates of the coastal Warri River, southern Nigeria was carried out from July 2014 to February 2015. Samples were collected from five longitudinal stations from headwater to mouth during high and low ...

  18. The Effect of Extremely Low Frequency Electromagnetic Fields on Visual Learning & Memory and Anatomical Structures of the Brain in Male Rhesus Monkeys

    Directory of Open Access Journals (Sweden)

    Elahe Tekieh

    2018-04-01

    Full Text Available Background: Humans in modern societies expose to substantially elevated levels of electromagnetic field (EMF emissions with different frequencies.The neurobiological effects of EMF have been the subject of debate and intensive research over the past few decades. Therefore, we evaluated the effects of EMF on visual learning and anatomical dimensions of the hippocampus and the prefrontal area (PFA in male Rhesus monkeys. Materials and Methods:In this study, four rhesus monkeys were irradiated by 0.7 microtesla ELF-EMF either at 5 or 30 Hz, 4 h a day, for 30 days. Alterations in visual learning and memory were assessed before and after irradiation phase by using a box designed that cchallenging animals for gaining rewards Also, the monkeys’ brains were scanned by using MRI technique one week before and one week after irradiation. The monkeys were anesthetized by intramuscular injection of ketamine hydrochloride (10–20 mg/kg and xylazine (0.2–0.4 mg/kg, and scanned with a 3-Tesla Magnetom, in axial, sagittal, and coronal planes using T2 weight­ed protocol with a slice thickness of 3 mm. The anatomical changes of hippocampus and the prefrontal area (PFA was measured by volumetric study. Results: Electromagnetic field exposure at a frequency of 30 Hz reduced the number of correct responses in the learning process and delayed memory formation in the two tested monkeys. While, ELF-EMF at 5 Hz had no effect on the visual learning and memory changes. No anatomical changes were found in the prefrontal area and the hippocampus at both frequencies. Conclusion: ELF-EMF irradiation at 30 Hz adversely affected visual learning and memory, pprobably through these changes apply through effects on other factors except changes in brain structure and anatomy.

  19. Maximum weight of greenhouse effect to global temperature variation

    International Nuclear Information System (INIS)

    Sun, Xian; Jiang, Chuangye

    2007-01-01

    Full text: The global average temperature has risen by 0.74 0 C since the late 19th century. Many studies have concluded that the observed warming in the last 50 years may be attributed to increasing concentrations of anthropogenic greenhouse gases. But some scientists have a different point of view. Global climate change is affected not only by anthropogenic activities, but also constraints in climate system natural factors. How much is the influencing weight of C02's greenhouse effects to the global temperature variation? Does global climate continue warming or decreasing in the next 20 years? They are two hot spots in global climate change. The multi-timescales analysis method - Empirical mode decomposition (EMD) is used to diagnose global annual mean air temperature dataset for land surface provided by IPCC and atmospheric content of C02 provided by the Carbon Dioxide Information Analysis Center (CDIAC) during 1881-2002. The results show that: Global temperature variation contains quasi-periodic oscillations on four timescales (3 yr, 6 yr, 20 yr and 60 yr, respectively) and a century-scale warming trend. The variance contribution of IMF1-IMF4 and trend is 17.55%, 11.34%, 6.77%, 24.15% and 40.19%, respectively. The trend and quasi-60 yr oscillation of temperature variation are the most prominent; C02's greenhouse effect on global temperature variation is mainly century-scale trend. The contribution of C02 concentration to global temperature variability is not more than 40.19%, whereas 59.81% contribution to global temperature variation is non-greenhouse effect. Therefore, it is necessary to re-study the dominant factors that induce the global climate change; It has been noticed that on the periods of 20 yr and 60 yr oscillation, the global temperature is beginning to decreased in the next 20 years. If the present C02 concentration is maintained, the greenhouse effect will be too small to countercheck the natural variation in global climate cooling in the next 20

  20. Anatomical features of renal artery in a black Kenyan population ...

    African Journals Online (AJOL)

    Knowledge of anatomical features of the renal artery is important in prediction, management and control of atherosclerotic renal artery stenosis. These features show population variations but data from black African populations are scarce. The aim of this study was therefore to describe the anatomical features of the renal ...

  1. 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

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

    Directory of Open Access Journals (Sweden)

    Pablo Delgado-Sánchez

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

  3. 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

    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. 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. 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.

  4. Environmental Variation and Cohort Effects in an Antarctic Predator

    Science.gov (United States)

    Garrott, Robert A.; Rotella, Jay J.; Siniff, Donald B.; Parkinson, Claire L.; Stauffer, Glenn E.

    2011-01-01

    Understanding the potential influence of environmental variation experienced by animals during early stages of development on their subsequent demographic performance can contribute to our understanding of population processes and aid in predicting impacts of global climate change on ecosystem functioning. Using data from 4,178 tagged female Weddell seal pups born into 20 different cohorts, and 30 years of observations of the tagged seals, we evaluated the hypothesis that environmental conditions experienced by young seals, either indirectly through maternal effects and/or directly during the initial period of juvenile nutritional independence, have long-term effects on individual demographic performance. We documented an approximately 3-fold difference in the proportion of each cohort that returned to the pupping colonies and produced a pup within the first 10 years after birth. We found only weak evidence for a correlation between annual environmental conditions during the juvenile-independence period and cohort recruitment probability. Instead, the data strongly supported an association between cohort recruitment probability and the regional extent of sea ice experienced by the mother during the winter the pup was in utero. We suggest that inter-annual variation in winter sea-ice extent influences the foraging success of pregnant seals by moderating the regional abundance of competing predators that cannot occupy areas of consolidated sea ice, and by directly influencing the abundance of mid-trophic prey species that are sea-ice obligates. We hypothesize that this environmentally-induced variation in maternal nutrition dictates the extent of maternal energetic investment in offspring, resulting in cohort variation in mean size of pups at weaning which, in turn, contributes to an individual?s phenotype and its ultimate fitness. These linkages between sea ice and trophic dynamics, combined with demonstrated and predicted changes in the duration and extent of sea

  5. Anatomical terminology in Ophthalmology

    OpenAIRE

    Abib, Fernando César; Oréfice, Fernando

    2005-01-01

    O objetivo deste artigo é informar à classe oftalmológica a existência da edição em língua portuguesa da Terminologia Anatômica Internacional, editada pela Federation Committee on Anatomical Terminology (FCAT). No Brasil a Terminologia Anatômica Internacional é traduzida pela Comissão de Terminologia Anatômica (CTA) da Sociedade Brasileira de Anatomia (SBA).The purpose of this article is inform ophthalmologists of the International Anatomical Terminology in the Portuguese language edited by t...

  6. Effect of canopy architectural variation on transpiration and thermoregulation

    Science.gov (United States)

    Linn, R.; Banerjee, T.

    2017-12-01

    One of the major scientific questions identified by the NGEE - Tropics campaign is the effect of disturbances such as forest fires, vegetation thinning and land use change on carbon, water and energy fluxes. Answers to such questions can help develop effective forest management strategies and shape policies to mitigate damages under natural and anthropogenic climate change. The absence of horizontal and vertical variation of forest canopy structure in current models is a major source of uncertainty in answering these questions. The current work addresses this issue through a bottom up process based modeling approach to systematically investigate the effect of forest canopy architectural variation on plant physiological response as well as canopy level fluxes. A plant biophysics formulation is used which is based on the following principles: (1) a model for the biochemical demand for CO2 as prescribed by photosynthesis models. This model can differentiate between photosynthesis under light-limited and nutrient-limited scenarios. (2) A Fickian mass transfer model including transfer through the laminar boundary layer on leaves that may be subjected to forced or free convection depending upon the mean velocity and the radiation load; (3) an optimal leaf water use strategy that maximizes net carbon gain for a given transpiration rate to describe the stomatal aperture variation; (4) a leaf-level energy balance to accommodate evaporative cooling. Such leaf level processes are coupled to solutions of atmospheric flow through vegetation canopies. In the first test case, different scenarios of top heavy and bottom heavy (vertical) foliage distributions are investigated within a one-dimensional framework where no horizontal heterogeneity of canopy structure is considered. In another test case, different spatial distributions (both horizontal and vertical) of canopy geometry (land use) are considered, where flow solutions using large eddy simulations (LES) are coupled to the

  7. Variation in the effect of carcass decontamination impacts the risk for consumers

    DEFF Research Database (Denmark)

    Ribeiro Duarte, Ana Sofia; Nauta, Maarten; Aabo, Søren

    2016-01-01

    •The variation of decontamination has an effect on consumer risk reduction.•The effect of variation on risk is lower when mean log reduction is high.•The effect of variation on risk also depends on initial carcass contamination.•The effect of decontamination should be expressed as consumer risk...

  8. Magnetohydrodynamic shock wave formation: Effect of area and density variation

    International Nuclear Information System (INIS)

    Sujith, R.I.

    2005-01-01

    The nonlinear steepening of finite amplitude magnetohydrodynamic (MHD) waves propagating perpendicular to the magnetic field is investigated. The nonlinear evolution of a planar fast magnetosonic wave in a homentropic flow field is understood well through simple waves. However, in situations where the wave is moving through a variable area duct or when the flow field is nonhomentropic, the concept of simple waves cannot be used. In the present paper, the quasi-one-dimensional MHD equations that include the effect of area variation and density gradients are solved using the wave front expansion technique. The analysis is performed for a perfectly conducting fluid and also for a weakly conducting fluid. Closed form solutions are obtained for the nonlinear evolution of the slope of the wave front in the limits of infinitely large and small conductivity. A general criterion for a compression wave to steepen into a shock is obtained. An analytical expression for the location of shock formation is derived. The effect of area variation and density gradient on shock formation is studied and examples highlighting the same are presented

  9. VARIATIONALLY-BASED EFFECTIVE DYNAMIC THICKNESS FOR LAMINATED GLASS BEAMS

    Directory of Open Access Journals (Sweden)

    Jaroslav Schmidt

    2017-11-01

    Full Text Available Laminated glass, consisting of glass layers connected with transparent foils, has found its applications in civil, automotive, or marine engineering. Due to a high contrast in layer properties, mechanical response of laminated glass structures cannot be predicted using classical laminate theories. On the other hand, engineering applications demand easy-to-use formulas of acceptable accuracy. This contribution addresses such simplified models for free vibrations of laminated glass beams, with the goal to determine their natural frequencies and modal damping properties. Our strategy is to approximate the complex behavior of a laminated structure with that of an equivalent monolithic beam. Its effective thickness is determined by the variational method proposed by Galuppi and Royer-Carfagni for static problems, which we extended for modal analysis. We show that this new approach overcomes inaccuracies of the currently used dynamic effective thickness model by López-Aenlle and Pelayo.

  10. Systematic significance of anatomical characterization in some euphorbiaceous species

    International Nuclear Information System (INIS)

    Zahra, N.B.; Shinwari, Z.K.

    2014-01-01

    The study was aimed to explore the systematic potential of anatomical characters for identification and delimitation among Euphorbia species. Eight species of leafy spurges of genus Euphorbia L. (Euphorbiaceae) were evaluated for variations in micro morphological characters of foliar epidermal anatomy. While anatomical observations are of importance in the assessments and appraisals, use of these characters as an effective tool in interpreting phyletic evaluations and systematic delineations has its limitations too. The epidermal cell wall in majority of species was wavy to undulate on both adaxial and abaxial surfaces. The observations made in this study indicate that there is not a single type of stomata which appears as characteristic of the genus Euphorbia. Also their distribution whether epistomatic or hypostomatic is not a genus-characteristic. The trichomes found were simple, unicellular or multicellular, uniseriate. Present investigation revealed the utility of both qualitative and quantitative characters in systematic studies; also the potential influence in the delimitation of species cannot be ignored. Our results show that the micro-morphology of anatomical characters play an important role in definition of taxa at species and sectional levels. (author)

  11. 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.

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

    DEFF Research Database (Denmark)

    Borjesson, Maria; Cherchi, Elisabetta; Bierlaire, Michel

    2013-01-01

    that variation in VTT between observed trips reflects the variation in the average VTT between individuals, which is usually made in equity analyses, will over-state the between-individual variation. The results suggest that if intraindividual variation in preferences is not taken into account, the negative...... equity effects of congestion charges are likely to be overestimated....

  13. 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.

  14. Accessory mental foramen: a rare anatomical finding

    Science.gov (United States)

    Thakur, Gagan; Thomas, Shaji; Thayil, Sumeeth Cyriac; Nair, Preeti P

    2011-01-01

    Accessory mental foramen (AMF) is a rare anatomical variation with a prevalence ranging from 1.4 to 10%. Even so, in order to avoid neurovascular complications, particular attention should be paid to the possible occurrence of one or more AMF during surgical procedures involving the mandible. Careful surgical dissection should be performed in the region so that the presence of AMF can be detected and the occurrence of a neurosensory disturbance or haemorrhage can be avoided. Although this anatomical variation is rare, it should be kept in mind that an AMF may exist. Trigeminal neuralgia was diagnosed. On the basis of diagnostic test results, peripheral neurectomy of mental nerve was planned. Failure to do neurectomy of mental nerve branch in the reported case, coming out from AMF, would have resulted in recurrence of pain and eventually failure of the procedure. PMID:22707601

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

    Science.gov (United States)

    van de Kerk, Madelon; Jones Littles, Chanda; Saucedo, Omar; Lorenzen, Kai

    2016-01-01

    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.

  16. The Effects of Phacoemulsification and Intraocular Lens Implantation on Anatomical and Functional Parameters in Patients with Primary Angle Closure: A Prospective Study. (An American Ophthalmological Society Thesis).

    Science.gov (United States)

    Traverso, Carlo Enrico; Cutolo, Carlo Alberto

    2017-08-01

    To investigate the clinical, anatomical, and patient-reported outcomes of phacoemulsification (PE) with intraocular lens implantation performed to treat primary angle closure (PAC) and primary angle-closure glaucoma (PACG). Patients were evaluated at baseline and at 6 months after PE. The examination included visual acuity, intraocular pressure (IOP), visual field, optic nerve head, endothelial cell count (ECC), aqueous depth, and ocular biometric parameters. Patient-reported visual function and health status were assessed. Coprimary outcome measures were IOP changes, angle widening, and patient-reported visual function; secondary outcome measures were visual acuity changes, use of IOP-lowering medications, and complications. Univariate and multivariate analyses were performed to determine the predictors of IOP change. Thirty-nine cases were identified, and postoperative data were analyzed for 59 eyes, 39 with PACG and 20 with PAC. Globally, PE resulted in a mean reduction in IOP of -6.33 mm Hg (95% CI, -8.64 to -4.01, P <.001). Aqueous depth and angle measurements improved ( P <.01), whereas ECC significantly decreased ( P <.001). Both corrected and uncorrected visual acuity improved ( P <.01). The EQ visual analog scale did not change ( P =.16), but VFQ-25 improved ( P <.01). The IOP-lowering effect of PE was greater in the PACG compared to the PAC group ( P =.04). In both groups, preoperative IOP was the most significant predictor of IOP change ( P <.01). No sight-threatening complications were recorded. Our data support the usefulness of PE in lowering the IOP in patients with PAC and PACG. Although PE resulted in several anatomical and patient-reported visual improvements, we observe that a marked decrease in ECC should be carefully weighed before surgery.

  17. Perceived Effect of Climate Variation on Food Crop Production in ...

    African Journals Online (AJOL)

    The study objective is to determine the perception of food crop farmers in Oyo state to climate variation as it affects their production, because the relationship between climate variation and food security is direct and Oyo State has enormous potentials to make Nigeria food secure. Multi-stage sampling technique was used to ...

  18. 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.)

  19. Anatomical influences on internally coupled ears in reptiles.

    Science.gov (United States)

    Young, Bruce A

    2016-10-01

    Many reptiles, and other vertebrates, have internally coupled ears in which a patent anatomical connection allows pressure waves generated by the displacement of one tympanic membrane to propagate (internally) through the head and, ultimately, influence the displacement of the contralateral tympanic membrane. The pattern of tympanic displacement caused by this internal coupling can give rise to novel sensory cues. The auditory mechanics of reptiles exhibit more anatomical variation than in any other vertebrate group. This variation includes structural features such as diverticula and septa, as well as coverings of the tympanic membrane. Many of these anatomical features would likely influence the functional significance of the internal coupling between the tympanic membranes. Several of the anatomical components of the reptilian internally coupled ear are under active motor control, suggesting that in some reptiles the auditory system may be more dynamic than previously recognized.

  20. Understanding anatomical terms.

    Science.gov (United States)

    Mehta, L A; Natrajan, M; Kothari, M L

    1996-01-01

    Words are our masters and words are our slaves, all depending on how we use them. The whole of medical science owes its origin to Greco-Roman culture and is replete with terms whose high sound is not necessarily accompanied by sound meaning. This is even more the case in the initial, pre-clinical years. Anatomical terminology seems bewildering to the initiate; and maybe that is a reason why love of anatomy as a subject does not always spill over through later years. Employing certain classifications of the origin of the anatomical terms, we have prepared an anthology that we hope will ease the student's task and also heighten the student's appreciation of the new terms. This centers on revealing the Kiplingian "how, why, when, where, what, and who" of a given term. This presentation should empower students to independently formulate a wide network of correlations once they understand a particular term. The article thus hopes to stimulate students' analytic and synthetic faculties as well. A small effort can reap large rewards in terms of enjoyment of the study of anatomy and the related subjects of histology, embryology, and genetics. It is helpful to teachers and students alike. This exercise in semantics and etymology does not demand of the student or his teacher any background in linguistics, grammar, Greek, Latin, Sanskrit, anatomy, or medicine.

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

    Science.gov (United States)

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

    2014-05-01

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

  2. Evaluation of the anatomic effect of physical therapy exercises for mobilization of lumbar spinal nerves and the dura mater in dogs.

    Science.gov (United States)

    Gruenenfelder, Fredrik I; Boos, Alois; Mouwen, Marco; Steffen, Frank

    2006-10-01

    To adapt and standardize neural tissue mobilization exercises, quantify nerve root movement, and assess the anatomic effects of lumbar spinal nerve and dural mobilization in dogs. 15 canine cadavers. 5 cadavers were used in the preliminary part of the study to adapt 3 neural tissue mobilization physical therapy exercises to canine anatomy. In the other 10 cadavers, the L4 to L7 nerve roots and the dura at the level of T13 and L1 were isolated and marked. Movements during the physical therapy exercises were standardized by means of goniometric control. Movement of the nerve roots in response to each exercise was digitally measured. The effects of body weight and crownrump length on the distance of nerve root movement achieved during each exercise were also assessed. Each exercise was divided into 4 steps, and the overall distance of neural movement achieved was compared with distances achieved between steps. Neural tissue mobilization exercises elicited visible and measurable movement of nerve roots L4 to L7 and of the dura at T13 and L1 in all cadavers. The physical therapy exercises evaluated had measurable effects on nerve roots L4 to L7 and the dura mater in the T13 and L1 segments. These exercises should be evaluated in clinical trials to validate their efficacy as primary treatments or ancillary postsurgical therapy in dogs with disorders of the thoracolumbar and lumbosacral segments of the vertebral column.

  3. 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

  4. Effects of posture and anatomical location on inter-recti distance measured using ultrasound imaging in parous women.

    Science.gov (United States)

    Gillard, S; Ryan, C G; Stokes, M; Warner, M; Dixon, J

    2018-04-01

    Cross-sectional repeated measures. To quantify the effects of posture and measurement site on the inter-recti distance (IRD) and investigate the reliability of IRD measurement using ultrasound imaging in different postures. The linea alba connects the rectus abdominis muscles anteriorly and the width is known as the IRD. The IRD is usually measured in crook-lying and is the primary outcome measure to assess for a divarication of recti abdominis (DRA). The effects of posture and measurement site on the IRD have not been investigated. Ultrasound imaging was used to measure IRD in 41 women ≥8 weeks postpartum. The IRD was measured at three sites (superior-umbilicus, umbilicus and inferior-umbilicus), in three postures (crook-lying, sitting and standing), and repeated one-week later. The effects of posture and site were investigated using one-way ANOVAs. Reliability was analysed using Intraclass correlation coefficients (ICCs), Bland Altman analyses, standard error of measurement and minimal detectable change. The IRD was wider when standing vs. lying at both the superior-umbilicus and umbilicus by 0.30 cm (95% CI 0.21 to 0.39) and 0.20 cm (0.11-0.30) respectively (p < 0.001). Measurements at the inferior-umbilicus were, on average, 1.6 and 2.1 cm narrower than superior-umbilicus and umbilicus sites, respectively (p < 0.001). There was high intra-rater reliability within-session (ICC 3.3 ) and between-session (ICC 3.1 ) at all sites measured. The IRD can be measured reliably at all sites and postures. The IRD is wider at superior-umbilicus and umbilicus when upright compared with lying. There is a difference in IRD between all sites measured. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Effect of dietary restriction on metabolic, anatomic and molecular traits in mice depends on the initial level of basal metabolic rate.

    Science.gov (United States)

    Brzek, Pawel; Ksiazek, Aneta; Dobrzyn, Agnieszka; Konarzewski, Marek

    2012-09-15

    Dietary restriction (DR)-related delay of ageing is hypothesized to be mediated by the reduction of the metabolic rate (MR). However, studies on the effect of DR on MR have produced equivocal results. We demonstrated that this lack of congruency can be due to a variation in the initial level of MR within a given pool of experimental subjects. We subjected laboratory mice from two line types divergently selected for basal MR (BMR) to 30% DR lasting 6 months to test whether the effect of DR depends on the initial variation in BMR and peak MR. BMR and peak MR were independently affected by DR. The effect of DR was stronger in line types with higher initial levels of MR. Line-type-specific changes in the proportions of body components explained contrasting effects of DR on the mass-corrected BMR, which decreased in the high-BMR line type and did not change in the low-BMR line type. We conclude that the initial variation in MR can significantly affect response to DR. However, we found no association between the level of MR and mechanisms underlying the susceptibility to or protection against oxidative stress.

  6. 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.)

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

    International Nuclear Information System (INIS)

    Papadakis, Antonios E.; Perisinakis, Kostas; Damilakis, John

    2014-01-01

    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 mod ) values were recorded. Image noise was measured at selected anatomical sites. The mAs 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 mod was lower than the preselected mAs with the exception of the 10-year-old phantom. In paediatric and adult phantoms, the mAs 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.)

  8. Effect of scapular external rotation on the axillary nerve during the arthroscopic Latarjet procedure: an anatomical investigation.

    Science.gov (United States)

    Reinares, Felipe; Werthel, Jean-David; Moraiti, Constantina; Valenti, Philippe

    2017-10-01

    The first purpose of this study is to measure the distance between the axillary nerve and the exit point of K-wires placed retrograde through the glenoid in the setting of an arthroscopic Latarjet procedure. The second objective is to evaluate whether manual external rotation of the scapula alters that distance. In seven fresh-frozen specimens, two 2.0-mm K-wires were drilled through the glenoid using an arthroscopic Latarjet retrograde glenoid guide. These were drilled into the glenoid at the 7- and 8-o'clock positions (right shoulders) and at the 4- and 5-o'clock positions (left). K-wires were oriented parallel to the glenoid articular surface and perpendicular to the long superoinferior axis of the glenoid, 7 mm medial to the joint surface. Two independent evaluators measured the distances between the axillary nerve and the exit point of the K-wires in the horizontal plane (AKHS for the superior K-wire and AKHI for the inferior K-wire) and in the vertical plane (AKV). Measurements were taken with the scapula left free and were repeated with the scapula placed at 15° and 30° of external rotation. With the scapula left free, scapular external rotation was 34° ± 2.3°. In this position, the AKHS was 2.5 ± 1.6, 6.3 ± 1.2 mm at 15° of external rotation (ER) and 11.4 ± 1.4 mm at 30° ER. The AKHI distance was 0.37 ± 1.6, 3.4 ± 1.4 and 10.6 ± 2.1 mm, respectively, for the scapula left free, at 15° ER and 30° of ER. The AKV distances were, respectively, 0.12 ± 0.2, 4.9 ± 1.6 and 9.9 ± 1.7 mm. The increase in all distances was statistically significant (p < 0.001). Increasing scapular external rotation significantly increases the distance between the axillary nerve and the exit point of the K-wires, increasing the margin of safety during this procedure. Therefore, increased external rotation of the scapula could be an effective tool to decrease the risk of iatrogenic axillary nerve injury. Cadaveric study, Level V.

  9. Effect Of Bulk Density Variation On The Compression Strength Of ...

    African Journals Online (AJOL)

    This paper reports a study conducted to assess the influence of variation of bulk density on compression strength of clay-bonded sand. Five sand mixes containing silica sand, sodium silicate gel (1 wt. % to 5 wt. %), potters' clay (2 wt. %), and about 5 wt. % water were produced. Each mix was divided into three portions to ...

  10. Variation in Primary Radioclimatic Variables, And Its Effects on ...

    African Journals Online (AJOL)

    The impact of these variables depends on the variation of the measured data of the primary radioclimatic parameters (temperature, relative humidity and atmospheric pressure) with height at lower troposphere. The data of the study was collected via two wireless weather station using Vantage pro2, one stationed at ground ...

  11. Evaluation of anatomical and physical properties of Khaya nthotheca

    African Journals Online (AJOL)

    The anatomical and physical properties of Khaya anthotheca (Welw.) C. DC wood from the transition forest of middle altitude (zone 1) and the humid dense forest of low altitude (zone 2) in the East of the Democratic Republic of Congo were evaluated to ascertain the effect of growth area on the anatomical and physical ...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-03-21

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

  13. 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.

    2011-03-01

    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.

  14. Effects of seasonal variations on thermoregulation of ostrich

    International Nuclear Information System (INIS)

    Basuony, H.A.M.

    2011-01-01

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

  15. The effects of FreeSurfer version, workstation type, and Macintosh operating system version on anatomical volume and cortical thickness measurements.

    Directory of Open Access Journals (Sweden)

    Ed H B M Gronenschild

    Full Text Available FreeSurfer is a popular software package to measure cortical thickness and volume of neuroanatomical structures. However, little if any is known about measurement reliability across various data processing conditions. Using a set of 30 anatomical T1-weighted 3T MRI scans, we investigated the effects of data processing variables such as FreeSurfer version (v4.3.1, v4.5.0, and v5.0.0, workstation (Macintosh and Hewlett-Packard, and Macintosh operating system version (OSX 10.5 and OSX 10.6. Significant differences were revealed between FreeSurfer version v5.0.0 and the two earlier versions. These differences were on average 8.8 ± 6.6% (range 1.3-64.0% (volume and 2.8 ± 1.3% (1.1-7.7% (cortical thickness. About a factor two smaller differences were detected between Macintosh and Hewlett-Packard workstations and between OSX 10.5 and OSX 10.6. The observed differences are similar in magnitude as effect sizes reported in accuracy evaluations and neurodegenerative studies.The main conclusion is that in the context of an ongoing study, users are discouraged to update to a new major release of either FreeSurfer or operating system or to switch to a different type of workstation without repeating the analysis; results thus give a quantitative support to successive recommendations stated by FreeSurfer developers over the years. Moreover, in view of the large and significant cross-version differences, it is concluded that formal assessment of the accuracy of FreeSurfer is desirable.

  16. A guide for effective anatomical vascularization studies: useful ex vivo methods for both CT and MRI imaging before dissection.

    Science.gov (United States)

    Renard, Yohann; Hossu, Gabriela; Chen, Bailiang; Krebs, Marine; Labrousse, Marc; Perez, Manuela

    2018-01-01

    The objective of this study was to develop a simple and useful injection protocol for imaging cadaveric vascularization and dissection. Mixtures of contrast agent and cast product should provide adequate contrast for two types of ex vivo imaging (MRI and CT) and should harden to allow gross dissection of the injected structures. We tested the most popular contrast agents and cast products, and selected the optimal mixture composition based on their availability and ease of use. All mixtures were first tested in vitro to adjust dilution parameters of each contrast agent and to fine-tune MR imaging acquisition sequences. Mixtures were then injected in 24 pig livers and one human pancreas for MR and computed tomography (CT) imaging before anatomical dissection. Colorized latex, gadobutrol and barite mixture met the above objective. Mixtures composed of copper sulfate (CuSO 4 ) gadoxetic acid (for MRI) and iodine (for CT) gave an inhomogeneous signal or extravasation of the contrast agent. Agar did not harden sufficiently for gross dissection but appears useful for CT and magnetic resonance imaging (MRI) studies without dissection. Silicone was very hard to inject but achieved the goals of the study. Resin is particularly difficult to use but could replace latex as an alternative for corrosion instead of dissection. This injection protocol allows CT and MRI images to be obtained of cadaveric vascularization and anatomical casts in the same anatomic specimen. Post-imaging processing software allow easy 3D reconstruction of complex anatomical structures using this technique. Applications are numerous, e.g. surgical training, teaching methods, postmortem anatomic studies, pathologic studies, and forensic diagnoses. © 2017 Anatomical Society.

  17. Planning tiger recovery: Understanding intraspecific variation for effective conservation

    Science.gov (United States)

    Wilting, Andreas; Courtiol, Alexandre; Christiansen, Per; Niedballa, Jürgen; Scharf, Anne K.; Orlando, Ludovic; Balkenhol, Niko; Hofer, Heribert; Kramer-Schadt, Stephanie; Fickel, Jörns; Kitchener, Andrew C.

    2015-01-01

    Although significantly more money is spent on the conservation of tigers than on any other threatened species, today only 3200 to 3600 tigers roam the forests of Asia, occupying only 7% of their historical range. Despite the global significance of and interest in tiger conservation, global approaches to plan tiger recovery are partly impeded by the lack of a consensus on the number of tiger subspecies or management units, because a comprehensive analysis of tiger variation is lacking. We analyzed variation among all nine putative tiger subspecies, using extensive data sets of several traits [morphological (craniodental and pelage), ecological, molecular]. Our analyses revealed little variation and large overlaps in each trait among putative subspecies, and molecular data showed extremely low diversity because of a severe Late Pleistocene population decline. Our results support recognition of only two subspecies: the Sunda tiger, Panthera tigris sondaica, and the continental tiger, Panthera tigris tigris, which consists of two (northern and southern) management units. Conservation management programs, such as captive breeding, reintroduction initiatives, or trans-boundary projects, rely on a durable, consistent characterization of subspecies as taxonomic units, defined by robust multiple lines of scientific evidence rather than single traits or ad hoc descriptions of one or few specimens. Our multiple-trait data set supports a fundamental rethinking of the conventional tiger taxonomy paradigm, which will have profound implications for the management of in situ and ex situ tiger populations and boost conservation efforts by facilitating a pragmatic approach to tiger conservation management worldwide. PMID:26601191

  18. Effects of reservoirs water level variations on fish recruitment

    Directory of Open Access Journals (Sweden)

    Fabíula T. de Lima

    2017-10-01

    Full Text Available ABSTRACT The construction of hydroelectric power plants has many social and environmental impacts. Among them, the impacts on fish communities, which habitats are drastically modified by dams, with consequences across the ecosystem. This study aimed to assess the influence of water level (WL variations in the reservoirs of the Itá and Machadinho hydroelectric plants on the recruitment of fish species from the upper Uruguay River in southern Brazil. The data analyzed resulted from the WL variation produced exclusively by the hydroelectric plants generation and were collected between the years 2001 and 2012. The results showed significant correlations between the abundance of juvenile fish and the hydrological parameters only for some reproductive guilds. The species that spawn in nests showed, in general, a clear preference for the stability in the WL of the reservoirs, while the species that spawn in macrophytes or that release demersal eggs showed no significant correlation between the abundance of juvenile fish and hydrological parameters. A divergence of results between the two reservoirs was observed between the species that release semi-dense eggs; a positive correlation with a more stable WL was only observed in the Machadinho reservoir. This result can be driven by a wider range of WL variation in Machadinho reservoir.

  19. Effects of temporal variation in temperature and density dependence on insect population dynamics

    Science.gov (United States)

    Understanding effects of environmental variation on insect populations is important in light of predictions about increasing future climatic variability. In order to understand the effects of changing environmental variation on population dynamics and life history evolution in insects one would need...

  20. 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

  1. 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. 2007 Wiley-Liss, Inc.

  2. Anatomical changes in the pharyngeal constrictors after chemo-irradiation of head and neck cancer and their dose-effect relationships: MRI-based study

    International Nuclear Information System (INIS)

    Popovtzer, Aron; Cao Yue; Feng, Felix Y.; Eisbruch, Avraham

    2009-01-01

    Purpose: Dysfunction of pharyngeal constrictors (PCs) after chemo-irradiation of head and neck (HN) cancer has been proposed as major cause of dysphagia. We conducted prospective MRI study to evaluate anatomical changes in the PCs after chemo-irradiation, to gain insight of the mechanism of their dysfunction and their dose-effect relationships. The PCs were compared to the sternocleidomastoid muscles (SCMs), which receive high doses but do not relate to swallowing. Patients and methods: Twelve patients with stage III-IV HN cancer underwent MRI before and 3 months after completing chemo-irradiation. T1- and T2-weighted signals and muscle thickness were evaluated for PCs (superior, middle, and inferior), and SCMs. Mean muscle doses were determined after registration with the planning CT. Results: T1-weighted signals decreased in both PCs and SCMs receiving >50 Gy (p 2 = 0.34, p = 0.01). The T2 signal changes in the PCs were significantly higher than the T2 changes in the SCMs (p 50 Gy gaining significantly more thickness than PCs receiving lesser doses (p = 0.02). In contrast, the SCM thickness decreased post-therapy (p = 0.002). Conclusions: These MRI-based findings, notably the differences between PCs and SCMs, suggest that underlying causes of PC dysfunction are inflammation and edema, likely consequential to acute mucositis affecting the submucosa-lying PCs. These results support reducing mean PC doses to ≤50 Gy, as well as reducing acute mucositis, to improve long-term dysphagia.

  3. Effects of extreme obliquity variations on the habitability of exoplanets.

    Science.gov (United States)

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

    2014-04-01

    We explore the impact of obliquity variations on planetary habitability in hypothetical systems with high mutual inclination. We show that large-amplitude, high-frequency obliquity oscillations on Earth-like exoplanets can suppress the ice-albedo feedback, increasing the outer edge of the habitable zone. We restricted our exploration to hypothetical systems consisting of a solar-mass star, an Earth-mass planet at 1 AU, and 1 or 2 larger planets. We verified that these systems are stable for 10(8) years with N-body simulations and calculated the obliquity variations induced by the orbital evolution of the Earth-mass planet and a torque from the host star. We ran a simplified energy balance model on the terrestrial planet to assess surface temperature and ice coverage on the planet's surface, and we calculated differences in the outer edge of the habitable zone for planets with rapid obliquity variations. For each hypothetical system, we calculated the outer edge of habitability for two conditions: (1) the full evolution of the planetary spin and orbit and (2) the eccentricity and obliquity fixed at their average values. We recovered previous results that higher values of fixed obliquity and eccentricity expand the habitable zone, but we also found that obliquity oscillations further expand habitable orbits in all cases. Terrestrial planets near the outer edge of the habitable zone may be more likely to support life in systems that induce rapid obliquity oscillations as opposed to fixed-spin planets. Such planets may be the easiest to directly characterize with space-borne telescopes.

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

    International Nuclear Information System (INIS)

    Liu Feng; Erickson, Beth; Peng Cheng; Li, X. Allen

    2012-01-01

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

  6. Anatomic Preformed Post: Case Report

    OpenAIRE

    Lamas Lara, César; Cirujano Dentista, Docente del Área de Operatoria Dental y Endodoncia de la Facultad de OdontoIogía de la UNMSM.; Alvarado Menacho, Sergio; Cirujano Dentista, Especialista en Rehabilitación Oral, Profesor Asociado del Área de Prótesis y Oclusión de la Facultad de Odontología de la UNMSM.; Pari Espinoza, Rosa; Alumna del 5to año de Odontología de la UNMSM.

    2014-01-01

    Nowadays, preformed posts are being used frequently, but they do not follow root canal anatomy. Obtaining a more anatomical form of the root canal and reducing the space of the cement, it would help to reduce the possibility of its eviction. This article details the process of making of an anatomical preformed post and the advantages that would represent its clinical use. En la actualidad los postes preformados se utilizan con mucha frecuencia, pero tienenla dificultad de no seguir la anat...

  7. 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.

  8. 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.

  9. Dissimilarity-based classification of anatomical tree structures

    DEFF Research Database (Denmark)

    Sørensen, Lauge Emil Borch Laurs; Lo, Pechin Chien Pau; Dirksen, Asger

    2011-01-01

    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...

  10. 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...

  11. Effects of variations in structural parameters on performance of switched parasitic arrays

    CSIR Research Space (South Africa)

    Mofolo, MRO

    2011-09-01

    Full Text Available to model random errors in such parameters. The effects of these variations on the performance of the SPA antenna are investigated using a numerical approach. Mutual coupling between the array elements is taken into consideration. The variations are modelled...

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

    Indian Academy of Sciences (India)

    Proton transfer; promoter modes; kinetic isotope effect. 1. Introduction. Kinetic isotope effect (KIE) is the dependence of the rate constant on the mass of the isotope of the atom in a chemical reaction. The primary kinetic isotope effect is the KIE when the bonds connecting that atom to the rest of the molecular frame are broken ...

  13. Organ/patient geometric variation in external beam radiotherapy and its effects

    International Nuclear Information System (INIS)

    Yan Di; Lockman, David

    2001-01-01

    Treatment variation in positioning of the organ/patient with respect to the radiation beams causes a temporal dose variation in critical normal tissues adjacent to the treatment target. This temporal variation induces uncertainties in understanding the normal tissue dose response, thereby limiting reliable treatment evaluation and optimization. The aim of this study is to model and analyze the temporal variation of organ dose distribution, and its effect on the biological effective dose. The study mainly focuses on the temporal dose variation caused by intertreatment organ motion/deformation and daily setup error. Sensitivity of the biological effective dose to organ/patient geometric variation, dose distribution, and treatment fractionation will be investigated. Significant deviation of the biological effective dose could be expected in a critical normal structure, even if the cumulative dose deviation in this structure is negligible. Patients with similar geometric variation characteristics can experience significantly different biological effective dose, and the differences are sensitive to the dose distribution and the total number of treatment fractions

  14. Radiographic evaluation of anatomical variables in maxilla and mandible in relation to dental implant placement

    Directory of Open Access Journals (Sweden)

    Poornima Chandra

    2016-01-01

    Conclusion: The location and morphology of anatomical structures of the jaws vary not only in different populations but also within the same population. The amount of bone available also showed variations in the same population and in the same individual on the right and left sides. The limiting anatomical structures govern the amount of bone available for possible implant placement.

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

    Science.gov (United States)

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

    2010-01-01

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

  16. 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.

  17. Numerical estimation of the effects of climatic variations on human ...

    African Journals Online (AJOL)

    temperature, humidity, solar radiation and wind speed) are used to develop a numerical model for estimating the effect of climatic changes on human thermal comfort in Botswana. Numerical values of energy load for four different comfort classes were ...

  18. 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.

  19. In vivo posterior cruciate ligament elongation in running activity after anatomic and non-anatomic anterior cruciate ligament reconstruction.

    Science.gov (United States)

    Tang, Jing; Thorhauer, Eric; Bowman, Karl; Fu, Freddie H; Tashman, Scott

    2017-04-01

    The goals of this study were to (1) investigate the in vivo elongation behaviour of the posterior cruciate ligament (PCL) during running in the uninjured knee and (2) evaluate changes in PCL elongation during running after anatomic or non-anatomic anterior cruciate ligament (ACL) reconstruction. Seventeen unilateral ACL-injured subjects were recruited after undergoing anatomic (n = 9) or non-anatomic (n = 8) ACL reconstruction. Bilateral high-resolution CT scans were obtained to produce 3D models. Anterolateral (AL) and posteromedial (PM) bundles insertion sites of the PCL were identified on the 3D CT scan reconstructions. Dynamic knee function was assessed during running using a dynamic stereo X-ray (DSX) system. The lengths of the AL and PM bundles were estimated from late swing through mid-stance. The contralateral knees served as normal controls. Control knees demonstrated a slight decrease in AL bundle and a significant decrease in PM bundle length following foot strike. Length and elongation patterns of the both bundles of the PCL in the anatomic ACL reconstruction group were similar to the controls. However, the change in dynamic PCL length was significantly greater in the non-anatomic group than in the anatomic reconstruction group after foot strike (p < 0.05). The AL bundle length decreased slightly, and the PM bundle length significantly decreased after foot strike during running in uninjured knees. Anatomic ACL reconstruction maintained normal PCL elongation patterns more effectively than non-anatomic ACL reconstruction during high-demand, functional loading. These results support the use of anatomic ACL reconstruction to achieve normal knee function in high-demand activities. Case-control study, Level III.

  20. The effect of longshore topographic variation on overwash modelling

    NARCIS (Netherlands)

    McCall, R.; Plant, N.; Van Thiel de Vries, J.S.M.

    2011-01-01

    This paper describes an application of the XBeach model to investigate the effect of longshore topographic variance on overwash. The model is used to simulate the morphological response of an eight-kilometer section of Santa Rosa Island, Florida, due to Hurricane Ivan (2004). The influence of

  1. Effect of seasonal drawdown variations on groundwater quality in ...

    African Journals Online (AJOL)

    user

    2013-07-24

    Jul 24, 2013 ... Igbinosa and Okoh (2009) reported the damaging conse- quences of leachate infiltration into groundwater bodies on life expectancy of such water consumers, while Quinn et al. (2006) enumerated its effect and that of delayed drawdown on moist plant productivity and wetland ecology. Several studies have ...

  2. Variation in the Protective Effect of Higher Education Against Depression*

    Science.gov (United States)

    Bauldry, Shawn

    2016-01-01

    Numerous studies document that higher education is associated with a reduced likelihood of depression. The protective effects of higher education, however, are known to vary across population subgroups. This study tests competing theories for who is likely to obtain a greater protective benefit from a college degree against depression through an analysis of data from the National Longitudinal Study of Adolescent Health and recently developed methods for analyzing heterogeneous treatment effects involving the use of propensity scores. The analysis examines how the effects of two “treatments” (at least some college education and attaining at least a four-year college degree) on latent depressive symptomology vary by background disadvantage, as indicated by having a low propensity for completing some college or attaining a four-year college degree. Results indicate that people from disadvantaged backgrounds realize a greater protective effect of higher education, either completing some college or attaining a four-year degree, against depressive symptomology than people from advantaged backgrounds. This pattern is more pronounced for people who attain at least a four-year degree than for people who complete at least some college education. PMID:27840772

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

    NARCIS (Netherlands)

    Davidge, Kristen M.; van Furth, Wouter R.; Agur, Anne; Cusimano, Michael

    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

  4. Tree growth variation in the tropical forest: understanding effects of temperature, rainfall and CO2.

    Science.gov (United States)

    Schippers, Peter; Sterck, Frank; Vlam, Mart; Zuidema, Pieter A

    2015-01-28

    Tropical forest responses to climatic variability have important consequences for global carbon cycling, but are poorly understood. As empirical, correlative studies cannot disentangle the interactive effects of climatic variables on tree growth, we used a tree growth model (IBTREE) to unravel the climate effects on different physiological pathways and in turn on stem growth variation. We parameterized the model for canopy trees of Toona ciliata (Meliaceae) from a Thai monsoon forest and compared predicted and measured variation from a tree-ring study over a 30-year period. We used historical climatic variation of minimum and maximum day temperature, precipitation and carbon dioxide (CO 2 ) in different combinations to estimate the contribution of each climate factor in explaining the inter-annual variation in stem growth. Running the model with only variation in maximum temperature and rainfall yielded stem growth patterns that explained almost 70% of the observed inter-annual variation in stem growth. Our results show that maximum temperature had a strong negative effect on the stem growth by increasing respiration, reducing stomatal conductance and thus mitigating a higher transpiration demand, and - to a lesser extent - by directly reducing photosynthesis. Although stem growth was rather weakly sensitive to rain, stem growth variation responded strongly and positively to rainfall variation owing to the strong inter-annual fluctuations in rainfall. Minimum temperature and atmospheric CO 2 concentration did not significantly contribute to explaining the inter-annual variation in stem growth. Our innovative approach - combining a simulation model with historical data on tree-ring growth and climate - allowed disentangling the effects of strongly correlated climate variables on growth through different physiological pathways. Similar studies on different species and in different forest types are needed to further improve our understanding of the sensitivity of

  5. Effect of variation of precursor concentration on structural ...

    Indian Academy of Sciences (India)

    lized in industrial and domestic fields as fuel. It is referred to as town or cooking gas. This gas is ... Takeuchi 2003), solar cells (Bach et al 1998; Grätzel 2001;. Adachi 2004). Several methods for the growth of TiO2 ... response to LPG and H2 at operating temperatures of 350 and 250. ◦. C, respectively. The effect of precursor ...

  6. Ecological effects of aphid abundance, genotypic variation, and contemporary evolution on plants.

    Science.gov (United States)

    Turley, Nash E; Johnson, Marc T J

    2015-07-01

    Genetic variation and contemporary evolution within populations can shape the strength and nature of species interactions, but the relative importance of these forces compared to other ecological factors is unclear. We conducted a field experiment testing the effects of genotypic variation, abundance, and presence/absence of green peach aphids (Myzus persicae) on the growth, leaf nitrogen, and carbon of two plant species (Brassica napus and Solanum nigrum). Aphid genotype affected B. napus but not S. nigrum biomass explaining 20 and 7% of the total variation, respectively. Averaging across both plant species, the presence/absence of aphids had a 1.6× larger effect size (Cohen's d) than aphid genotype, and aphid abundance had the strongest negative effects on plant biomass explaining 29% of the total variation. On B. napus, aphid genotypes had different effects on leaf nitrogen depending on their abundance. Aphids did not influence leaf nitrogen in S. nigrum nor leaf carbon in either species. We conducted a second experiment in the field to test whether contemporary evolution could affect plant performance. Aphid populations evolved in as little as five generations, but the rate and direction of this evolution did not consistently vary between plant species. On one host species (B. napus), faster evolving populations had greater negative effects on host plant biomass, with aphid evolutionary rate explaining 23% of the variation in host plant biomass. Together, these results show that genetic variation and evolution in an insect herbivore can play important roles in shaping host plant ecology.

  7. Environmental and geographic variables are effective surrogates for genetic variation in conservation planning.

    Science.gov (United States)

    Hanson, Jeffrey O; Rhodes, Jonathan R; Riginos, Cynthia; Fuller, Richard A

    2017-11-28

    Protected areas buffer species from anthropogenic threats and provide places for the processes that generate and maintain biodiversity to continue. However, genetic variation, the raw material for evolution, is difficult to capture in conservation planning, not least because genetic data require considerable resources to obtain and analyze. Here we show that freely available environmental and geographic distance variables can be highly effective surrogates in conservation planning for representing adaptive and neutral intraspecific genetic variation. We obtained occurrence and genetic data from the IntraBioDiv project for 27 plant species collected over the European Alps using a gridded sampling scheme. For each species, we identified loci that were potentially under selection using outlier loci methods, and mapped their main gradients of adaptive and neutral genetic variation across the grid cells. We then used the cells as planning units to prioritize protected area acquisitions. First, we verified that the spatial patterns of environmental and geographic variation were correlated, respectively, with adaptive and neutral genetic variation. Second, we showed that these surrogates can predict the proportion of genetic variation secured in randomly generated solutions. Finally, we discovered that solutions based only on surrogate information secured substantial amounts of adaptive and neutral genetic variation. Our work paves the way for widespread integration of surrogates for genetic variation into conservation planning.

  8. Variations in ultraviolet extinction: effect of polarization revisited

    International Nuclear Information System (INIS)

    Greenberg, J.M.; Chlewicki, G.; Rijksuniversiteit Groningen

    1987-01-01

    The alignment of the particles responsible for the polarization and visual extinction is shown to provide a basis for changing the saturation level of the ultraviolet extinction without changing the particle sizes. If the particles are well aligned, it is predicted that there should be significantly lower extinction in the ultraviolet relative to the visible for stars viewed perpendicular to magnetic-field lines (maximum polarization) as compared with those viewed across the field lines. Preliminary evidence for such an effect is noted in Carina. (author)

  9. Effect of α variation on a prospective experiment to detect variation of me/mp in diatomic molecules

    International Nuclear Information System (INIS)

    Beloy, K.; Borschevsky, A.; Schwerdtfeger, P.; Flambaum, V. V.

    2011-01-01

    We consider the influence of variation in the fine structure constant α on a promising experiment proposed by DeMille et al. to search for variation in the electron-to-proton mass ratio μ using diatomic molecules [DeMille et al., Phys. Rev. Lett. 100, 043202 (2008)]. The proposed experiment involves spectroscopically probing the splitting between two nearly degenerate vibrational levels supported by different electronic potentials. Here we demonstrate that this splitting may be equally or more sensitive to variation in α as to variation in μ. For the anticipated experimental precision, this implies that the α variation may not be negligible, as previously assumed, and further suggests that the method could serve as a competitive means to search for α variation as well.

  10. Anatomical modeling of the bronchial tree

    Science.gov (United States)

    Hentschel, Gerrit; Klinder, Tobias; Blaffert, Thomas; Bülow, Thomas; Wiemker, Rafael; Lorenz, Cristian

    2010-02-01

    The bronchial tree is of direct clinical importance in the context of respective diseases, such as chronic obstructive pulmonary disease (COPD). It furthermore constitutes a reference structure for object localization in the lungs and it finally provides access to lung tissue in, e.g., bronchoscope based procedures for diagnosis and therapy. This paper presents a comprehensive anatomical model for the bronchial tree, including statistics of position, relative and absolute orientation, length, and radius of 34 bronchial segments, going beyond previously published results. The model has been built from 16 manually annotated CT scans, covering several branching variants. The model is represented as a centerline/tree structure but can also be converted in a surface representation. Possible model applications are either to anatomically label extracted bronchial trees or to improve the tree extraction itself by identifying missing segments or sub-trees, e.g., if located beyond a bronchial stenosis. Bronchial tree labeling is achieved using a naïve Bayesian classifier based on the segment properties contained in the model in combination with tree matching. The tree matching step makes use of branching variations covered by the model. An evaluation of the model has been performed in a leaveone- out manner. In total, 87% of the branches resulting from preceding airway tree segmentation could be correctly labeled. The individualized model enables the detection of missing branches, allowing a targeted search, e.g., a local rerun of the tree-segmentation segmentation.

  11. Effects of Abrupt Variations of Solar Wind Dynamic Pressure on the High-Latitude Ionosphere

    Directory of Open Access Journals (Sweden)

    Igino Coco

    2011-01-01

    Full Text Available We show the results of a statistical study on the effects in the high-latitude ionosphere of abrupt variations of solar wind dynamic pressure, using Super Dual Auroral Radar Network (SuperDARN data in both hemispheres. We find that, during periods of quiet ionospheric conditions, the amount of radar backscatter increases when a variation in the dynamic pressure occurs, both positive (increase of the pressure and negative (decrease of the pressure. We also investigate the behaviour of the Cross-Polar Cap Potential (CPCP during pressure variations and show preliminary results.

  12. 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...

  13. 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.

  14. Custom anatomic healing abutments

    Directory of Open Access Journals (Sweden)

    Vinayak S Gowda

    2016-01-01

    Full Text Available Dental implants with their increasing success rates and predictability of final outcome are fast becoming the treatment of choice for replacing missing teeth. Considering the success of immediate implant placement in reducing tissue loss and achieving good esthetic results, is making it a more popular treatment modality in implant dentistry. Understanding the management of gingival tissues in relation to implants to obtain maximum esthetics is of utmost importance. The use of provisional abutments and immediate temporization has a proven track record of their ability to produce optimal esthetics and to guide the tissue response during the healing phase. With careful patient selection and execution, customized healing abutments can provide an effective method to enhance the esthetic and emergence profile for anterior implant restorations.

  15. 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.

  16. Intervention effects and relative variation as dimensions in experts' use of visual inference.

    Science.gov (United States)

    Furlong, M J; Wampold, B E

    1982-01-01

    Recent research indicates that when analyzing graphically presented single-subject data, subjects trained in visual inference appear to attend to large changes between phases regardless of relative variation and do not differentiate among common intervention effect patterns. In this follow-up study, experts in applied behavior analysis completed a free-sort task designed to assess the effects of these dimensions on their use of visual inference. The results indicate that they tended to differentiate among common intervention effect patterns but did not attend to relative variation in the data.

  17. Variation Of The Effects Of Adopol EVS-9279X On The Emulsion ...

    African Journals Online (AJOL)

    The effects of Adopol EVS-9279X on the emulsion and film properties of emulsion paint using 5%-10% w/w sample formulations have been examined. Variation of these effects with time was investigated in this study using the same 5%-10% w/w sample formulations. The emulsion and film properties were measured at four ...

  18. The Effect of Intrapulse RF Variation on Bunch Train Energy Spread (LCC-0030)

    International Nuclear Information System (INIS)

    Nantista, C.

    2004-01-01

    In this note, we present a brief analysis of the effect of small variations in amplitude and phase in the accelerating rf pulse in addition to the deliberate pulse shaping on the energy deviation along a bunch train and the effects of pulse-to-pulse fluctuations

  19. Effects of variations in fuel pellet composition and size on mixed-oxide fuel pin performance

    International Nuclear Information System (INIS)

    Makenas, B.J.; Jensen, B.W.; Baker, R.B.

    1980-10-01

    Experiments have been conducted which assess the effects on fuel pin performance of specific minor variations from nominal in both fuel pellet size and pellet composition. Such pellets are generally referred to in the literature as rogue pellets. The effect of these rogue pellets on fuel pin and reactor performance is shown to be minimal

  20. Variational Effective Index Method for 3D Vectorial Scattering Problems in Photonics: TE Polarization

    NARCIS (Netherlands)

    Ivanova, Alyona; Stoffer, Remco; Kauppinen, L.J.; Hammer, Manfred

    2009-01-01

    In order to reduce the computational effort we develop a method for 3D-to-2D dimensionality reduction of scattering problems in photonics. Contrary to the `standard' Effective Index Method the effective parameters of the reduced problem are always rigorously defined using the variational technique,

  1. Effect of a large-scale distance variation of gravitational constant on the orbital elements of celestial bodies

    International Nuclear Information System (INIS)

    Li, L.-S.

    2009-01-01

    The effects of the variation of the gravitational constant with distance on the variation of the orbital elements of celestial objects are examined. The theoretical results show clearly that the large distance variation of the gravitational constant results in the periodic variation of the semi-major axis, eccentricity, longitude of the perihelion and the mean longitude, but it results in the secular variation of the longitude of the perihelion and the mean longitude, no secular variation for other orbital elements. As an example, the effects on four planets are estimated. Discussion and conclusion are drawn.

  2. 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.

  3. How accurate is anatomic limb alignment in predicting mechanical limb alignment after total knee arthroplasty?

    Science.gov (United States)

    Lee, Seung Ah; Choi, Sang-Hee; Chang, Moon Jong

    2015-10-27

    Anatomic limb alignment often differs from mechanical limb alignment after total knee arthroplasty (TKA). We sought to assess the accuracy, specificity, and sensitivity for each of three commonly used ranges for anatomic limb alignment (3-9°, 5-10° and 2-10°) in predicting an acceptable range (neutral ± 3°) for mechanical limb alignment after TKA. We also assessed whether the accuracy of anatomic limb alignment was affected by anatomic variation. This retrospective study included 314 primary TKAs. The alignment of the limb was measured with both anatomic and mechanical methods of measurement. We also measured anatomic variation, including the femoral bowing angle, tibial bowing angle, and neck-shaft angle of the femur. All angles were measured on the same full-length standing anteroposterior radiographs. The accuracy, specificity, and sensitivity for each range of anatomic limb alignment were calculated and compared using mechanical limb alignment as the reference standard. The associations between the accuracy of anatomic limb alignment and anatomic variation were also determined. The range of 2-10° for anatomic limb alignment showed the highest accuracy, but it was only 73 % (3-9°, 65 %; 5-10°, 67 %). The specificity of the 2-10° range was 81 %, which was higher than that of the other ranges (3-9°, 69 %; 5-10°, 67 %). However, the sensitivity of the 2-10° range to predict varus malalignment was only 16 % (3-9°, 35 %; 5-10°, 68 %). In addition, the sensitivity of the 2-10° range to predict valgus malalignment was only 43 % (3-9°, 71 %; 5-10°, 43 %). The accuracy of anatomical limb alignment was lower for knees with greater femoral (odds ratio = 1.2) and tibial (odds ratio = 1.2) bowing. Anatomic limb alignment did not accurately predict mechanical limb alignment after TKA, and its accuracy was affected by anatomic variation. Thus, alignment after TKA should be assessed by measuring mechanical alignment rather than anatomic

  4. 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.

  5. Unification of Sinonasal Anatomical Terminology

    Directory of Open Access Journals (Sweden)

    Voegels, Richard Louis

    2015-07-01

    Full Text Available The advent of endoscopy and computed tomography at the beginning of the 1980s brought to rhinology a revival of anatomy and physiology study. In 1994, the International Conference of Sinus Disease was conceived because the official “Terminologia Anatomica”[1] had little information on the detailed sinonasal anatomy. In addition, there was a lack of uniformity of terminology and definitions. After 20 years, a new conference has been held. The need to use the same terminology led to the publication by the European Society of Rhinology of the “European Position Paper on the Anatomical Terminology of the Internal Nose and Paranasal Sinuses,” that can be accessed freely at www.rhinologyjournal.com. Professor Valerie Lund et al[2] wrote this document reviewing the anatomical terms, comparing to the “Terminology Anatomica” official order to define the structures without eponyms, while respecting the embryological development and especially universalizing and simplifying the terms. A must-read! The text's purpose lies beyond the review of anatomical terminology to universalize the language used to refer to structures of the nasal and paranasal cavities. Information about the anatomy, based on extensive review of the current literature, is arranged in just over 50 pages, which are direct and to the point. The publication may be pleasant reading for learners and teachers of rhinology. This text can be a starting point and enables searching the universal terminology used in Brazil, seeking to converge with this new European proposal for a nomenclature to help us communicate with our peers in Brazil and the rest of the world. The original text of the European Society of Rhinology provides English terms that avoided the use of Latin, and thus fall beyond several national personal translations. It would be admirable if we created our own cross-cultural adaptation of this new suggested anatomical terminology.

  6. [Cellular subcutaneous tissue. Anatomic observations].

    Science.gov (United States)

    Marquart-Elbaz, C; Varnaison, E; Sick, H; Grosshans, E; Cribier, B

    2001-11-01

    We showed in a companion paper that the definition of the French "subcutaneous cellular tissue" considerably varied from the 18th to the end of the 20th centuries and has not yet reached a consensus. To address the anatomic reality of this "subcutaneous cellular tissue", we investigated the anatomic structures underlying the fat tissue in normal human skin. Sixty specimens were excised from the surface to the deep structures (bone, muscle, cartilage) on different body sites of 3 cadavers from the Institut d'Anatomie Normale de Strasbourg. Samples were paraffin-embedded, stained and analysed with a binocular microscope taking x 1 photographs. Specimens were also excised and fixed after subcutaneous injection of Indian ink, after mechanic tissue splitting and after performing artificial skin folds. The aspects of the deep parts of the skin greatly varied according to their anatomic localisation. Below the adipose tissue, we often found a lamellar fibrous layer which extended from the interlobular septa and contained horizontally distributed fat cells. No specific tissue below the hypodermis was observed. Artificial skin folds concerned either exclusively the dermis, when they were superficial or included the hypodermis, but no specific structure was apparent in the center of the fold. India ink diffused to the adipose tissue, mainly along the septa, but did not localise in a specific subcutaneous compartment. This study shows that the histologic aspects of the deep part of the skin depend mainly on the anatomic localisation. Skin is composed of epidermis, dermis and hypodermis and thus the hypodermis can not be considered as being "subcutaneous". A difficult to individualise, fibrous lamellar structure in continuity with the interlobular septa is often found under the fat lobules. This structure is a cleavage line, as is always the case with loose connective tissues, but belongs to the hypodermis (i.e. fat tissue). No specific tissue nor any virtual space was

  7. Ontogenetic variation in cold tolerance plasticity in Drosophila: is the Bogert effect bogus?

    Science.gov (United States)

    Mitchell, Katherine A.; Sinclair, Brent J.; Terblanche, John S.

    2013-03-01

    Ontogenetic variation in plasticity is important to understanding mechanisms and patterns of thermal tolerance variation. The Bogert effect postulates that, to compensate for their inability to behaviourally thermoregulate, less-mobile life stages of ectotherms are expected to show greater plasticity of thermal tolerance than more-mobile life stages. We test this general prediction by comparing plasticity of thermal tolerance (rapid cold-hardening, RCH) between mobile adults and less-mobile larvae of 16 Drosophila species. We find an RCH response in adults of 13 species but only in larvae of four species. Thus, the Bogert effect is not as widespread as expected.

  8. Ecological and evolutionary consequences of tri-trophic interactions: Spatial variation and effects of plant density.

    Science.gov (United States)

    Abdala-Roberts, Luis; Parra-Tabla, Víctor; Moreira, Xoaquín; Ramos-Zapata, José

    2017-02-01

    The factors driving variation in species interactions are often unknown, and few studies have made a link between changes in interactions and the strength of selection. We report on spatial variation in functional responses by a seed predator (SP) and its parasitic wasps associated with the herb Ruellia nudiflora . We assessed the influence of plant density on consumer responses and determined whether density effects and spatial variation in functional responses altered natural selection by these consumers on the plant. We established common gardens at two sites in Yucatan, Mexico, and planted R. nudiflora at two densities in each garden. We recorded fruit output and SP and parasitoid attack; calculated relative fitness (seed number) under scenarios of three trophic levels (accounting for SP and parasitoid effects), two trophic levels (accounting for SP but not parasitoid effects), and one trophic level (no consumer effects); and compared selection strength on fruit number under these scenarios across sites and densities. There was spatial variation in SP recruitment, whereby the SP functional response was negatively density-dependent at one site but density-independent at the other; parasitoid responses were density-independent and invariant across sites. Site variation in SP attack led, in turn, to differences in SP selection on fruit output, and parasitoids did not alter SP selection. There were no significant effects of density at either site. Our results provide a link between consumer functional responses and consumer selection on plants, which deepens our understanding of geographic variation in the evolutionary outcomes of multitrophic interactions. © 2017 Botanical Society of America.

  9. A study on parameter variation effects on battery packs for electric vehicles

    Science.gov (United States)

    Zhou, Long; Zheng, Yuejiu; Ouyang, Minggao; Lu, Languang

    2017-10-01

    As one single cell cannot meet power and driving range requirement in an electric vehicle, the battery packs with hundreds of single cells connected in parallel and series should be constructed. The most significant difference between a single cell and a battery pack is cell variation. Not only does cell variation affect pack energy density and power density, but also it causes early degradation of battery and potential safety issues. The cell variation effects on battery packs are studied, which are of great significant to battery pack screening and management scheme. In this study, the description for the consistency characteristics of battery packs was first proposed and a pack model with 96 cells connected in series was established. A set of parameters are introduced to study the cell variation and their impacts on battery packs are analyzed through the battery pack capacity loss simulation and experiments. Meanwhile, the capacity loss composition of the battery pack is obtained and verified by the temperature variation experiment. The results from this research can demonstrate that the temperature, self-discharge rate and coulombic efficiency are the major affecting parameters of cell variation and indicate the dissipative cell equalization is sufficient for the battery pack.

  10. Gene expression variation in Drosophila melanogaster due to rare transposable element insertion alleles of large effect.

    Science.gov (United States)

    Cridland, Julie M; Thornton, Kevin R; Long, Anthony D

    2015-01-01

    Transposable elements are a common source of genetic variation that may play a substantial role in contributing to gene expression variation. However, the contribution of transposable elements to expression variation thus far consists of a handful of examples. We used previously published gene expression data from 37 inbred Drosophila melanogaster lines from the Drosophila Genetic Reference Panel to perform a genome-wide assessment of the effects of transposable elements on gene expression. We found thousands of transcripts with transposable element insertions in or near the transcript and that the presence of a transposable element in or near a transcript is significantly associated with reductions in expression. We estimate that within this example population, ∼2.2% of transcripts have a transposable element insertion, which significantly reduces expression in the line containing the transposable element. We also find that transcripts with insertions within 500 bp of the transcript show on average a 0.67 standard deviation decrease in expression level. These large decreases in expression level are most pronounced for transposable element insertions close to transcripts and the effect diminishes for more distant insertions. This work represents the first genome-wide analysis of gene expression variation due to transposable elements and suggests that transposable elements are an important class of mutation underlying expression variation in Drosophila and likely in other systems, given the ubiquity of these mobile elements in eukaryotic genomes. Copyright © 2015 by the Genetics Society of America.

  11. Dyslexia, neurolinguistic ability, and anatomical variation of the planum temporale.

    Science.gov (United States)

    Morgan, A E; Hynd, G W

    1998-06-01

    This article addresses the relationship between patterns of planum temporale symmetry/asymmetry and dyslexia and neurolinguistic abilities. Considerable research indicates that dyslexic individuals typically do not display the predominant pattern of leftward planum temporale asymmetry. Variable findings on the structural basis of symmetry are due partially to measurement issues, which are examined in some detail in this critical review. The physiological basis of symmetry may be reduced neuronal elimination in the right planum, although other alternatives are offered. Theories are offered to explain how symmetrical plana are related to dyslexia, and it is evident that symmetrical plana are not sufficient to produce dyslexia. However, some evidence suggests that nonleftward plana asymmetry is associated with deficits in verbal comprehension, phonological decoding, and expressive language. It is concluded that nonleftward asymmetry is associated with linguistic deficits, but that explanatory theories need to be further developed. Among the many issues that need to be addressed, future research needs to determine whether the relationship between patterns of planum temporale symmetry/asymmetry and linguistic ability is specific to dyslexia or if asymmetry covaries lawfully with linguistic abilities in nondyslexic populations.

  12. Sparse Decomposition and Modeling of Anatomical Shape Variation

    DEFF Research Database (Denmark)

    Sjöstrand, Karl; Rostrup, Egill; Ryberg, Charlotte

    2007-01-01

    Recent advances in statistics have spawned powerful methods for regression and data decomposition that promote sparsity, a property that facilitates interpretation of the results. Sparse models use a small subset of the available variables and may perform as well or better than their full counter...

  13. Sparse decomposition and modeling of anatomical shape variation

    DEFF Research Database (Denmark)

    Sjöstrand, Karl; Rostrup, Egill; Ryberg, Charlotte

    2007-01-01

    Recent advances in statistics have spawned powerful methods for regression and data decomposition that promote sparsity, a property that facilitates interpretation of the results. Sparse models use a small subset of the available variables and may perform as well or better than their full counter...

  14. Case Report: Anatomic variation of celiac and testicular arteries ...

    African Journals Online (AJOL)

    Anatomy Journal of Africa. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 3, No 3 (2014) >. Log in or Register to get access to full text downloads.

  15. Anatomical Variation of Position and Location of the Fibula Nutrient ...

    African Journals Online (AJOL)

    Design: Cross-sectional descriptive study. Subjects: Two hundred right and left dry fibulas for male and female Kenyans were obtained. Setting: Department of Human Anatomy, University of Nairobi and the Osteology Department, National Museums of Kenya, Nairobi. Methods: The number and position of the nutrient ...

  16. Anatomical variation: T1 spina bifida occulta. Radiological findings

    Directory of Open Access Journals (Sweden)

    Guglielmo Manenti, MD, PhD

    2017-03-01

    Full Text Available We report a 26-year-old male patient who was admitted to our emergency department after a traffic accident and who suffered from neck pain. We have found accidentally a dorsal spinous process schisis, a very rare vertebral abnormality, that we recognized in the X-rays imaging performed for the study of the lung parenchyma.

  17. Anatomical variation: T1 spina bifida occulta. Radiological findings.

    Science.gov (United States)

    Manenti, Guglielmo; Iundusi, Riccardo; Picchi, Eliseo; Marsico, Salvatore; D'Onofrio, Adolfo; Rossi, Giorgia; Tarantino, Umberto; Floris, Roberto

    2017-03-01

    We report a 26-year-old male patient who was admitted to our emergency department after a traffic accident and who suffered from neck pain. We have found accidentally a dorsal spinous process schisis, a very rare vertebral abnormality, that we recognized in the X-rays imaging performed for the study of the lung parenchyma.

  18. Anatomical Variations of the Sphenoid Sinus and Nearby ...

    African Journals Online (AJOL)

    Background: To describe the relationship of optic nerves and internal carotid arteries to sphenoid sinus using Computerized Tomography (CT) in a black African population. Methods: We retrospectively reviewed both the coronal and axial CT images of the paranasal sinuses and brain of 110 patients which were obtained ...

  19. 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

  20. The effects of local control station design variation on plant risk

    International Nuclear Information System (INIS)

    O'Hara, J.

    1989-01-01

    The existence of human engineering deficiencies at local control stations (LCSs) was addressed in a study (NUREG/CR-3696) conducted by the Pacific Northwest Laboratory (PNL). PNL concluded that the existence of these human factors deficiencies at safety significant LCSs increases the potential for operator errors that could be detrimental to plant and public safety. However, PNL did not specific analysis to evaluate the effects of LCS design variations on human performance, on plant risk, or on the cost benefit feasibility of upgrading LCSs. The purpose of the present investigation was to conduct such an analysis. The specific objectives of the research were (1) to further define important local control stations, human factors related LCS design variations, and typical human engineering deficiencies (HEDs) at LCSs; (2) to determine the effect of LCS design variations on human performance, i.e., on risk-significant human errors (HEs); (3) to determine the effect of LCS-induced human performance variation on plant risk as measured by core melt frequency (CMF); and (4) to determine whether LCS improvements (upgrades in LCS design to mitigate HEDs) are feasible in a scoping-type value-impact analysis. The results can be summarized as follows. There was an overall effect of LCS variations on human performance. The transition from the worst LCS configuration to the best resulted in an absolute reduction or improvement of 0.82 in mean HEP (reduction by a factor of 20). The transition from low to high levels of FC was associated with a 0.46 (86%) reduction in mean HEP. The majority of the effect was accounted for in the transition from the low to medium levels. The Panel Design dimension also had an effect on human performance although not as large as functional centralization. Upgrading from a low to high panel design resulted in a 0.29 (69%) reduction in mean HEP

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

    NARCIS (Netherlands)

    Sanny, M.A.I.

    2012-01-01

    The aim of this thesis was first to identify the major technological and managerial factors and to investigate their contribution to variation in acrylamide concentrations. The second aim was to investigate the effect of technological and managerial control measures on the concentration and

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

    Science.gov (United States)

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

    2006-01-01

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

  3. Effects of Variation of Particle Size and Weight Fraction on the ...

    African Journals Online (AJOL)

    The effects of variation of particle size and weight fraction on the tensile strength and Young's modulus of periwinkle shell reinforced polyester composite have been investigated. Particulate reinforced polyester composites incorporating varying amounts of periwinkle shell particles (10, 20, 30, 35, 40 and 45wt %) of different ...

  4. Effect of slurry mixture variation on the quality of biogas produced ...

    African Journals Online (AJOL)

    This paper reports the effect of slurry mixture variations on the quality of biogas produced from chicken droppings. Chicken droppings were anaerobically digested to generate biogas as a sustainable alternative energy source for rural household energy requirements, in place of firewood. Samples of the chicken dropping ...

  5. An Exploration of the Effects of Cycle Time and Force Variations on ...

    African Journals Online (AJOL)

    This study investigated the effects of two intermittent task parameters on muscle fatigue, namely cycle time and force level variation. Of particular interest was whether a constant low-level underlying force would contribute to fatigue. Twelve students participated in four experimental conditions, each lasting 8 minutes.

  6. 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.

  7. 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

    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

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

    NARCIS (Netherlands)

    Sanny, M.A.I.

    2012-01-01

    The aim of this thesis was first to identify the major technological and managerial factors and to investigate their contribution to variation in acrylamide concentrations.  The second aim was to investigate the effect of technological and managerial control measures on the concentration and

  9. The effect of Experimental Law Variations on the Super 14 Rugby ...

    African Journals Online (AJOL)

    The aim of this study was to determine whether experimental law variations (ELV) was effective in making rugby union matches more appealing to spectators by improving continuity. All the teams of the 2006 and 2008 Super 14 rugby tournament were used in this study. Three hundred and seventy games were recorded on ...

  10. effects of load and speed variations in a modified closed loop v/f

    African Journals Online (AJOL)

    2012-11-03

    Nov 3, 2012 ... Abstract. This paper investigates the effects of load and reference speed variations in a modified closed loop v/f induction motor drive. A modified approach, involving the addition of a low frequency boost voltage, is developed and adopted as an enhancement to the conventional closed loop v/f speed.

  11. Variation in Local-Scale Edge Effects: Mechanisms and landscape Context

    Science.gov (United States)

    Therese M. Donovan; Peter W. Jones; Elizabeth M. Annand; Frank R. Thompson III

    1997-01-01

    Ecological processes near habitat edges often differ from processes away from edges. Yet, the generality of "edge effects" has been hotly debated because results vary tremendously. To understand the factors responsible for this variation, we described nest predation and cowbird distribution patterns in forest edge and forest core habitats on 36 randomly...

  12. Principal Stratification: A Tool for Understanding Variation in Program Effects across Endogenous Subgroups

    Science.gov (United States)

    Page, Lindsay C.; Feller, Avi; Grindal, Todd; Miratrix, Luke; Somers, Marie-Andree

    2015-01-01

    Increasingly, researchers are interested in questions regarding treatment-effect variation across partially or fully latent subgroups defined not by pretreatment characteristics but by postrandomization actions. One promising approach to address such questions is principal stratification. Under this framework, a researcher defines endogenous…

  13. The Effects of Phonological Neighborhoods on Pronunciation Variation in Conversational Speech

    Science.gov (United States)

    Yao, Yao

    2011-01-01

    This dissertation investigates the effects of phonological neighborhoods on pronunciation variation in conversational speech. Phonological neighbors are defined as words that are different in one and only one phoneme by addition, deletion and substitution. Phonological neighborhood density refers to the number of neighbors a certain word has. …

  14. Some variations in petrography of South African Karoo dolerites and the effects thereof on aggregate properties

    CSIR Research Space (South Africa)

    Leyland, R

    2014-01-01

    Full Text Available -1 Engineering Geology for Society and Territory - Volume 5 Some Variations in Petrography of South African Karoo Dolerites and the Effects Thereof on Aggregate Properties Robert Leyland Abstract The Karoo Dolerite Suite in South Africa is an important...

  15. Some variations in petrography of South African Karoo dolerites and the effects thereof on aggregate properties

    CSIR Research Space (South Africa)

    Leyland, R

    2015-01-01

    Full Text Available -1 Engineering Geology for Society and Territory - Volume 5, pp 65-69 Some Variations in Petrography of South African Karoo Dolerites and the Effects Thereof on Aggregate Properties Robert Leyland Abstract The Karoo Dolerite Suite in South Africa...

  16. Effect of power variation on wettability and optical properties of co ...

    Indian Academy of Sciences (India)

    Abstract. The present paper deals with deposition of titanium and zirconium oxynitride films prepared from co- sputtering titanium and zirconium targets by reactive RF magnetron sputtering. The effect of power variation on various properties of the deposited films is analysed. The film gets transformed from amorphous to well ...

  17. 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

    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

  18. Variation Of The Effects Of Adopol EVS-9279X On The Emulsion ...

    African Journals Online (AJOL)

    vinyl acetate) and acrylic resin have been examined. Variation of these effects with time was investigated in this study using 5%-10% w/w sample formulations. The emulsion and film properties were measured at 4 weekly intervals. Results ...

  19. 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.

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

    NARCIS (Netherlands)

    Khachatryan, A.G.; van Goor, F.A.; Verschuur, Jeroen W.J.; Boller, Klaus 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

  1. Effects of anatomic conformation on three-dimensional motion of the caudal lumbar and lumbosacral portions of the vertebral column of dogs.

    Science.gov (United States)

    Benninger, Monika I; Seiler, Gabriela S; Robinson, Leanne E; Ferguson, Stephen J; Bonél, Harald M; Busato, André R; Lang, Johann

    2006-01-01

    To determine the association between the 3-dimensional (3-D) motion pattern of the caudal lumbar and lumbosacral portions of the canine vertebral column and the morphology of vertebrae, facet joints, and intervertebral disks. Vertebral columns of 9 German Shepherd Dogs and 16 dogs of other breeds with similar body weights and body conditions. Different morphometric parameters of the vertebral column were assessed by computed tomography (CT) and magnetic resonance imaging. Anatomic conformation and the 3-D motion pattern were compared, and correlation coefficients were calculated. Total range of motion for flexion and extension was mainly associated with the facet joint angle, the facet joint angle difference between levels of the vertebral column in the transverse plane on CT images, disk height, and lever arm length. Motion is a complex process that is influenced by the entire 3-D conformation of the lumbar portion of the vertebral column. In vivo dynamic measurements of the 3-D motion pattern of the lumbar and lumbosacral portions of the vertebral column will be necessary to further assess biomechanics that could lead to disk degeneration in dogs.

  2. Promising neuroprotective strategies for traumatic spinal cord injury with a focus on the differential effects among anatomical levels of injury [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Antigona Ulndreaj

    2017-10-01

    Full Text Available Traumatic spinal cord injury (SCI is a devastating condition of motor, sensory, and autonomic dysfunction. The significant cost associated with the management and lifetime care of patients with SCI also presents a major economic burden. For these reasons, there is a need to develop and translate strategies that can improve outcomes following SCI. Given the challenges in achieving regeneration of the injured spinal cord, neuroprotection has been at the forefront of clinical translation. Yet, despite many preclinical advances, there has been limited translation into the clinic apart from methylprednisolone (which remains controversial, hypertensive therapy to maintain spinal cord perfusion, and early decompressive surgery. While there are several factors related to the limited translational success, including the clinical and mechanistic heterogeneity of human SCI, the misalignment between animal models of SCI and clinical reality continues to be an important factor. Whereas most clinical cases are at the cervical level, only a small fraction of preclinical research is conducted in cervical models of SCI. Therefore, this review highlights the most promising neuroprotective and neural reparative therapeutic strategies undergoing clinical assessment, including riluzole, hypothermia, granulocyte colony-stimulating factor, glibenclamide, minocycline, Cethrin (VX-210, and anti-Nogo-A antibody, and emphasizes their efficacy in relation to the anatomical level of injury. Our hope is that more basic research will be conducted in clinically relevant cervical SCI models in order to expedite the transition of important laboratory discoveries into meaningful treatment options for patients with SCI.

  3. 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.

  4. 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.

  5. Plant genetic variation mediates an indirect ecological effect between belowground earthworms and aboveground aphids.

    Science.gov (United States)

    Singh, Akanksha; Braun, Julia; Decker, Emilia; Hans, Sarah; Wagner, Agnes; Weisser, Wolfgang W; Zytynska, Sharon E

    2014-10-21

    Interactions between aboveground and belowground terrestrial communities are often mediated by plants, with soil organisms interacting via the roots and aboveground organisms via the shoots and leaves. Many studies now show that plant genetics can drive changes in the structure of both above and belowground communities; however, the role of plant genetic variation in mediating aboveground-belowground interactions is still unclear. We used an earthworm-plant-aphid model system with two aphid species (Aphis fabae and Acyrthosiphon pisum) to test the effect of host-plant (Vicia faba) genetic variation on the indirect interaction between the belowground earthworms (Eisenia veneta) on the aboveground aphid populations. Our data shows that host-plant variety mediated an indirect ecological effect of earthworms on generalist black bean aphids (A. fabae), with earthworms increasing aphid growth rate in three plant varieties but decreasing it in another variety. We found no effect of earthworms on the second aphid species, the pea aphid (A. pisum), and no effect of competition between the aphid species. Plant biomass was increased when earthworms were present, and decreased when A. pisum was feeding on the plant (mediated by plant variety). Although A. fabae aphids were influenced by the plants and worms, they did not, in turn, alter plant biomass. Previous work has shown inconsistent effects of earthworms on aphids, but we suggest these differences could be explained by plant genetic variation and variation among aphid species. This study demonstrates that the outcome of belowground-aboveground interactions can be mediated by genetic variation in the host-plant, but depends on the identity of the species involved.

  6. Effect of monensin and monensin and tylosin combination on feed intake variation of feedlot steers.

    Science.gov (United States)

    Stock, R A; Laudert, S B; Stroup, W W; Larson, E M; Parrott, J C; Britton, R A

    1995-01-01

    A trial involving four commercial feedlots and an individual feeding trial evaluated the effect of monensin and monensin/tylosin on intake variation and deaths from digestive disorders. Four commercial feedlots in Texas and Colorado fed 2,904 yearling crossbred steers (340 kg) high-grain diets containing approximately 82% grain, 8% silage and alfalfa hay, 4% fat, and 6% supplement (DM basis). Steers were allotted randomly to one of three monensin/tylosin levels: 1) no monensin or tylosin (control); 2) 22 mg/kg of monensin and 11 mg/kg of tylosin; or 3) 33 mg/kg of monensin and 11 mg/kg of tylosin. Monensin/tylosin reduced DMI (P tylosin reduce feed intake variation among individual steers within a pen of steers. Pen means mask individual animal variation to the point that it is difficult to detect treatment differences.

  7. Effect of Viscosity Variation on the Micropolar Fluid Squeeze Film Lubrication of a Short Journal Bearing

    Directory of Open Access Journals (Sweden)

    N. B. Naduvinamani

    2013-01-01

    Full Text Available A theoretical study of the effect of the viscosity variation on the squeeze film performance of a short journal bearing operating with micropolar fluid is presented. The modified Reynolds equation accounting for the viscosity variation in micropolar fluid is mathematically derived. To obtain a closed form solution, the short bearing approximation under constant load is considered. The modified Reynolds equation is solved for the fluid film pressure and then the bearing characteristics, such as obtaining the load carrying capacity and the squeeze film time. According to the results evaluated, the micropolar fluid as a lubricant improves the squeeze film characteristics and results in a longer bearing life, whereas the viscosity variation factor decreases the load carrying capacity and squeezes film time. The result is compared with the corresponding Newtonian case.

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

    Directory of Open Access Journals (Sweden)

    B. LAKSHMI

    2015-08-01

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

  9. Effect of mass variation on dynamics of tethered system in orbital maneuvering

    Science.gov (United States)

    Sun, Liang; Zhao, Guowei; Huang, Hai

    2018-05-01

    In orbital maneuvering, the mass variation due to fuel consumption has an obvious impact on the dynamics of tethered system, which cannot be neglected. The contributions of the work are mainly shown in two aspects: 1) the improvement of the model; 2) the analysis of dynamics characteristics. As the mass is variable, and the derivative of the mass is directly considered in the traditional Lagrange equation, the expression of generalized force is complicated. To solve this problem, the coagulated derivative is adopted in the paper; besides, the attitude dynamics equations derived in this paper take into account the effect of mass variation and the drift of orbital trajectory at the same time. The bifurcation phenomenon, the pendular motion angular frequency, and amplitudes of tether vibration revealed in this paper can provide a reference for the parameters and controller design in practical engineering. In the article, a dumbbell model is adopted to analyze the dynamics of tethered system, in which the mass variation of base satellite is fully considered. Considering the practical application, the case of orbital transfer under a transversal thrust is mainly studied. Besides, compared with the analytical solutions of librational angles, the effects of mass variation on stability and librational characteristic are studied. Finally, in order to make an analysis of the effect on vibrational characteristic, a lumped model is introduced, which reveals a strong coupling of librational and vibrational characteristics.

  10. 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. © 2013.

  11. 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

    2017-01-01

    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...... alleles, the Inuit show, at most, a slight increase in load compared to European, East Asian, and African populations. Specifically, we observe recessive model suggest that the Inuit have...

  12. Seasonal variation of radon level and radon effective doses in the ...

    Indian Academy of Sciences (India)

    Because of the variations of the catacomb ventilation system, the equilibrium factor between radon and its progeny ranges from 0.14 to 0.48. The tour guides are exposed to an average estimated annual effective dose ranging from 0.21 to 0.52 mSv y-1 and the visitors from 0.88 to 2.28 Sv y-1. The effective doses the ...

  13. Intervention effects and relative variation as dimensions in experts' use of visual inference

    OpenAIRE

    Furlong, Michael J.; Wampold, Bruce E.

    1982-01-01

    Recent research indicates that when analyzing graphically presented single-subject data, subjects trained in visual inference appear to attend to large changes between phases regardless of relative variation and do not differentiate among common intervention effect patterns. In this follow-up study, experts in applied behavior analysis completed a free-sort task designed to assess the effects of these dimensions on their use of visual inference. The results indicate that they tended to differ...

  14. 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.

  15. 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)

  16. Effects of common germ-line genetic variation in cell cycle genes on ovarian cancer survival

    DEFF Research Database (Denmark)

    Song, H.; Hogdall, E.; Ramus, S.J.

    2008-01-01

    PURPOSE: Somatic alterations have been shown to correlate with ovarian cancer prognosis and survival, but less is known about the effects on survival of common inherited genetic variation. Of particular interest are genes involved in cell cycle pathways, which regulate cell division and could...... plausibly influence clinical characteristics of multiple tumors types. EXPERIMENTAL DESIGN: We examined associations between common germ-line genetic variation in 14 genes involved in cell cycle pathway (CCND1, CCND2, CCND3, CCNE1, CDKN1A, CDKN1B, CDKN2A, CDKN2B, CDKN2C, CDKN2D, CDK2, CDK4, CDK6, and RB1....... CONCLUSION: It is unlikely that common variants in cell cycle pathways examined above associated with moderate effect in survival after diagnosis of ovarian cancer. Much larger studies will be needed to exclude common variants with small effects Udgivelsesdato: 2008/2/15...

  17. The effect of conjunctions on the transit timing variations of exoplanets

    Energy Technology Data Exchange (ETDEWEB)

    Nesvorný, David [Department of Space Studies, Southwest Research Institute, 1050 Walnut Street, Suite 300, Boulder, CO 80302 (United States); Vokrouhlický, David, E-mail: davidn@boulder.swri.edu, E-mail: vokrouhl@cesnet.cz [Institute of Astronomy, Charles University, V Holešovičkách 2, CZ-18000 Prague 8 (Czech Republic)

    2014-07-20

    We develop an analytic model for transit timing variations produced by orbital conjunctions between gravitationally interacting planets. If the planetary orbits have tight orbital spacing, which is a common case among the Kepler planets, the effect of a single conjunction can be best described as: (1) a step-like change of the transit timing ephemeris with subsequent transits of the inner planet being delayed and those of the outer planet being sped up, and (2) a discrete change in sampling of the underlying oscillations from eccentricity-related interaction terms. In the limit of small orbital eccentricities, our analytic model gives explicit equations for these effects as a function of the mass and orbital separation of planets. We point out that a detection of the conjunction effect in real data is of crucial importance for the physical characterization of planetary systems from transit timing variations.

  18. Take away body parts! An investigation into the use of 3D-printed anatomical models in undergraduate anatomy education.

    Science.gov (United States)

    Smith, Claire F; Tollemache, Nicholas; Covill, Derek; Johnston, Malcolm

    2018-01-01

    Understanding the three-dimensional (3D) nature of the human form is imperative for effective medical practice and the emergence of 3D printing creates numerous opportunities to enhance aspects of medical and healthcare training. A recently deceased, un-embalmed donor was scanned through high-resolution computed tomography. The scan data underwent segmentation and post-processing and a range of 3D-printed anatomical models were produced. A four-stage mixed-methods study was conducted to evaluate the educational value of the models in a medical program. (1) A quantitative pre/post-test to assess change in learner knowledge following 3D-printed model usage in a small group tutorial; (2) student focus group (3) a qualitative student questionnaire regarding personal student model usage (4) teaching faculty evaluation. The use of 3D-printed models in small-group anatomy teaching session resulted in a significant increase in knowledge (P = 0.0001) when compared to didactic 2D-image based teaching methods. Student focus groups yielded six key themes regarding the use of 3D-printed anatomical models: model properties, teaching integration, resource integration, assessment, clinical imaging, and pathology and anatomical variation. Questionnaires detailed how students used the models in the home environment and integrated them with anatomical learning resources such as textbooks and anatomy lectures. In conclusion, 3D-printed anatomical models can be successfully produced from the CT data set of a recently deceased donor. These models can be used in anatomy education as a teaching tool in their own right, as well as a method for augmenting the curriculum and complementing established learning modalities, such as dissection-based teaching. Anat Sci Educ 11: 44-53. © 2017 American Association of Anatomists. © 2017 American Association of Anatomists.

  19. [Geographic variations in freshwater molluscs].

    Science.gov (United States)

    Vinarskiĭ, M V

    2012-01-01

    The phenomenon of geographic variation is known in practically all taxa of living beings. However, the reality of this phenomenon in freshwater molluscs (snails and bivalves) has many times been questioned in the past. It was accepted that these animals do not demonstrate spatially-oriented variation, where specific "local race" is arisen in each specific habitat. Till the beginning of 1970s, there was no statistical evidence that geographic clines in freshwater molluscs really exist. However, a few species of freshwater molluscs has been studied in this respect so far, therefore it is almost impossible to draw any general patterns of geographical variation in this group of animals. Most species of freshwater molluscs studied to the date exhibit statistically significant decrease of their body size in the south-north direction. Perhaps, it may be explained by decrease of the duration of the growth season in high latitudes. Some species of freshwater snails demonstrate clinal changes in shell proportions. This allows to reject subspecies separation within these species since diagnostic characters of such "subspecies" may blur when geographic variation is taken into consideration. The data on geographic variation in anatomical traits in freshwater molluscs is much more scarce. At least one species of pond snails (Lymnaea terebra) demonstrates clinal variation in proportions of the copulative apparatus in the south-north direction. Further studies of geographic variation in freshwater molluscs should reveal whether it is truly adaptive, i.e. whether geographical clines have underlying genetic basis. Otherwise, the clines may arise as a result of direct modifying effect of a habitat.

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

    DEFF Research Database (Denmark)

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

    2000-01-01

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

  1. Experimental Study on the Effects of Stress Variations on the Permeability of Feldspar-Quartz Sandstone

    Directory of Open Access Journals (Sweden)

    Fugang Wang

    2017-01-01

    Full Text Available The multistage and discontinuous nature of the injection process used in the geological storage of CO2 causes reservoirs to experience repeated loading and unloading. The reservoir permeability changes caused by this phenomenon directly impact the CO2 injection process and the process of CO2 migration in the reservoirs. Through laboratory experiments, variations in the permeability of sandstone in the Liujiagou formation of the Ordos CO2 capture and storage (CCS demonstration project were analyzed using cyclic variations in injection pressure and confining pressure and multistage loading and unloading. The variation in the micropore structure and its influence on the permeability were analyzed based on micropore structure tests. In addition, the effects of multiple stress changes on the permeability of the same type of rock with different clay minerals content were also analyzed. More attention should be devoted to the influence of pressure variations on permeability in evaluations of storage potential and studies of CO2 migration in reservoirs in CCS engineering.

  2. The Effects of Predator Evolution and Genetic Variation on Predator-Prey Population-Level Dynamics.

    Science.gov (United States)

    Cortez, Michael H; Patel, Swati

    2017-07-01

    This paper explores how predator evolution and the magnitude of predator genetic variation alter the population-level dynamics of predator-prey systems. We do this by analyzing a general eco-evolutionary predator-prey model using four methods: Method 1 identifies how eco-evolutionary feedbacks alter system stability in the fast and slow evolution limits; Method 2 identifies how the amount of standing predator genetic variation alters system stability; Method 3 identifies how the phase lags in predator-prey cycles depend on the amount of genetic variation; and Method 4 determines conditions for different cycle shapes in the fast and slow evolution limits using geometric singular perturbation theory. With these four methods, we identify the conditions under which predator evolution alters system stability and shapes of predator-prey cycles, and how those effect depend on the amount of genetic variation in the predator population. We discuss the advantages and disadvantages of each method and the relations between the four methods. This work shows how the four methods can be used in tandem to make general predictions about eco-evolutionary dynamics and feedbacks.

  3. Teaching For All? Variation in the Effects of Teach For America

    OpenAIRE

    Penner, Emily Kathryn

    2014-01-01

    Teach For America (TFA) is a high-profile alternative teacher certification program that seeks to provide high-quality teachers to students in low-income schools. While a growing body of research examines the average impact of TFA, few researchers examine how its impacts may vary across students and whether it positively impacts all children. This dissertation broadens our understanding of the impacts of TFA by examining variation in its effectiveness across a number of dimensions. The first ...

  4. 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

  5. Effect of agrowastes, pH and temperature variation on the growth of ...

    African Journals Online (AJOL)

    The effect of pH and temperature variations on the growth of Volvariella volvacea cultivated on various agricultural wastes singly and in various combinations was studied. A pH range of 5.5 to 8.5 recorded the maximum mycelia yield and the highest mycelia weight was recorded at pH 6.5. The mycelia yield decreased at pH ...

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

    OpenAIRE

    Bogaers, Lise

    2011-01-01

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

  7. The Effects of Phonological Neighborhoods on Pronunciation Variation in Conversational Speech

    OpenAIRE

    Yao, Yao

    2011-01-01

    This dissertation investigates the effects of phonological neighborhoods on pronunciation variation in conversational speech. Phonological neighbors are defined as words that are different in one and only one phoneme by addition, deletion and substitution. Phonological neighborhood density refers to the number of neighbors a certain word has.Previous research has shown that phonological neighbors impede auditory perception, but facilitate lexical production. As a result, words from dense neig...

  8. Regional variations and the effects of age and gender on glutamate concentrations in the human brain☆

    OpenAIRE

    Sailasuta, Napapon; Ernst, Thomas; Chang, Linda

    2007-01-01

    Proton magnetic resonance spectroscopy was performed at 3 T using the echo time-averaged point-resolved spectroscopy method to determine the effects of age, gender and brain region on glutamate (Glu) concentrations in the healthy human brain. Thirty healthy men and 20 healthy women aged between 21 and 71 years were studied. Significant regional variations of Glu concentrations were observed. Glu concentration in the gray matter (GM) was approximately 25% higher than that in the white matter. ...

  9. ANATOMIC STRUCTURE OF CAMPANULA ROTUNDIFOLIA L. GRASS

    OpenAIRE

    V. N. Bubenchikova; E. A. Nikitin

    2017-01-01

    The article present results of the study for a anatomic structure of Campanula rotundifolia grass from Campanulaceae family. Despite its dispersion and application in folk medicine, there are no data about its anatomic structure, therefore to estimate the indices of authenticity and quality of raw materials it is necessary to develop microdiagnostical features in the first place, which could help introducing of thisplant in a medical practice. The purpose of this work is to study anatomical s...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-11-15

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

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

    International Nuclear Information System (INIS)

    Paul, Jijo; Bauer, Ralf W.; Maentele, Werner; Vogl, Thomas J.

    2011-01-01

    Objective: The purpose of this study was to evaluate image fusion in dual energy computed tomography for detecting various anatomic structures based on the effect on contrast enhancement, contrast-to-noise ratio, signal-to-noise ratio and image quality. Material and methods: Forty patients underwent a CT neck with dual energy mode (DECT under a Somatom Definition flash Dual Source CT scanner (Siemens, Forchheim, Germany)). Tube voltage: 80-kV and Sn140-kV; tube current: 110 and 290 mA s; collimation-2 x 32 x 0.6 mm. Raw data were reconstructed using a soft convolution kernel (D30f). Fused images were calculated using a spectrum of weighting factors (0.0, 0.3, 0.6 0.8 and 1.0) generating different ratios between the 80- and Sn140-kV images (e.g. factor 0.6 corresponds to 60% of their information from the 80-kV image, and 40% from the Sn140-kV image). CT values and SNRs measured in the ascending aorta, thyroid gland, fat, muscle, CSF, spinal cord, bone marrow and brain. In addition, CNR values calculated for aorta, thyroid, muscle and brain. Subjective image quality evaluated using a 5-point grading scale. Results compared using paired t-tests and nonparametric-paired Wilcoxon-Wilcox-test. Results: Statistically significant increases in mean CT values noted in anatomic structures when increasing weighting factors used (all P ≤ 0.001). For example, mean CT values derived from the contrast enhanced aorta were 149.2 ± 12.8 Hounsfield Units (HU), 204.8 ± 14.4 HU, 267.5 ± 18.6 HU, 311.9 ± 22.3 HU, 347.3 ± 24.7 HU, when the weighting factors 0.0, 0.3, 0.6, 0.8 and 1.0 were used. The highest SNR and CNR values were found in materials when the weighting factor 0.6 used. The difference CNR between the weighting factors 0.6 and 0.3 was statistically significant in the contrast enhanced aorta and thyroid gland (P = 0.012 and P = 0.016, respectively). Visual image assessment for image quality showed the highest score for the data reconstructed using the weighting factor 0

  12. Circadian variation of the effects of immobility on symptoms of restless legs syndrome.

    Science.gov (United States)

    Michaud, Martin; Dumont, Marie; Paquet, Jean; Desautels, Alex; Fantini, Maria Livia; Montplaisir, Jacques

    2005-07-01

    It is now well established that symptoms of restless legs syndrome (RLS) are worsened by immobility and that their severity fluctuates according to a circadian pattern with a maximum occurring in the late evening or during the night. However, no study has ever attempted to dissociate these two effects. The objective of this study was to evaluate the nycthemeral variations in the effects of duration of immobility on symptoms of RLS. A 28-hour modified constant routine protocol. Sleep Disorders Center, Montreal Sacré-Coeur Hospital. Seven patients with primary RLS (3 men, 4 women; mean age: 43.9 years) and seven controls matched for age (42.4 years) and gender. None. A 40-minute Suggested Immobilization Test (SIT) was repeated every 2 hours during the 28-hour protocol in order to quantify both subjective leg discomfort and periodic leg movements (PLM). Regarding leg discomfort, a two-way ANOVA performed on patients' data revealed a significant interaction (p = 0.037) between Time within the SIT and Time of day. Simple effect analyses performed to decompose the interaction showed that the increase in leg discomfort with duration of immobility was found only on SIT 7, 8, 9, 10 and 12, which corresponds to the period between 21:20 and 08:00. In addition, in patients, a significant circadian variation (p immobility is closely linked to their intrinsic circadian variation.

  13. MR urography: Anatomical and quantitative information on ...

    African Journals Online (AJOL)

    MR urography: Anatomical and quantitative information on congenital malformations in children. Maria Karaveli, Dimitrios Katsanidis, Ioannis Kalaitzoglou, Afroditi Haritanti, Anastasios Sioundas, Athanasios Dimitriadis, Kyriakos Psarrakos ...

  14. THE EFFECT OF VARIATION CONCRETE CUBE OF AXIAL LOAD ON ULTRASONIC PULSE VELOCITY TRANSMITTER

    Directory of Open Access Journals (Sweden)

    Faqih Ma’arif

    2015-05-01

    The test result showed that the increase of ultrasonic pulse velocity effect on cube II due to axial load variation was optimum at 0,35P0 and was minimum at 0,7P0, if compared to the one without axial load, the results were 4,17% and 11,60 respectively. The decrease of pulse velocity on cube III due to axial load variation was at 0,25P0 and 0,7P0; if compared to the one without axial load the result were 0,47% and 20,87% respectively. And the increase of ultrasonic pulse velocity effect on cube IV due to axial load variation was optimum at 0,35P0 and was minimum at 0,7P0; if compared to the one without axial load the result were 0,52% and 21,63% respectively. The maximum limit of effective load step at structure experiencing compressive load ranged from 0,35P0 up to 0,4P0. At high stress level, the crack that occurred was spread evenly to the concrete cubic components and was giving an exponential equation y = y= 5,11e0,0467x. The result of analysis of cubes II, III and IV showed that on paired sample t-test 0,00<0,025, the significant value (2-tailed (0,00<(0,025; meaning there was a difference of pulse velocity due to axial load variation on concrete cube.

  15. Intraspecific variation in fruit-frugivore interactions: effects of fruiting neighborhood and consequences for seed dispersal.

    Science.gov (United States)

    Guerra, Tadeu J; Dayrell, Roberta L C; Arruda, André J; Dáttilo, Wesley; Teixido, Alberto L; Messeder, João V S; Silveira, Fernando A O

    2017-10-01

    The extent of specialization/generalization continuum in fruit-frugivore interactions at the individual level remains poorly explored. Here, we investigated the interactions between the Neotropical treelet Miconia irwinii (Melastomataceae) and its avian seed dispersers in Brazilian campo rupestre. We built an individual-based network to derive plant degree of interaction specialization regarding disperser species. Then, we explored how intraspecific variation in interaction niche breadth relates to fruit availability on individual plants in varying densities of fruiting conspecific neighbors, and how these factors affect the quantity of viable seeds dispersed. We predicted broader interaction niche breadths for individuals with larger fruit crops in denser fruiting neighborhoods. The downscaled network included nine bird species and 15 plants, which varied nearly five-fold in their degree of interaction specialization. We found positive effects of crop size on visitation and fruit removal rates, but not on degree of interaction specialization. Conversely, we found that an increase in the density of conspecific fruiting neighbors both increased visitation rate and reduced plant degree of interaction specialization. We suggest that tracking fruit-rich patches by avian frugivore species is the main driver of density-dependent intraspecific variation in plants' interaction niche breadth. Our study shed some light on the overlooked fitness consequences of intraspecific variation in interaction niches by showing that individuals along the specialization/generalization continuum may have their seed dispersed with similar effectiveness. Our study exemplifies how individual-based networks linking plants to frugivore species that differ in their seed dispersal effectiveness can advance our understanding of intraspecific variation in the outcomes of fruit-frugivore interactions.

  16. Dual and mixed nonsymmetric stress-based variational formulations for coupled thermoelastodynamics with second sound effect

    Science.gov (United States)

    Tóth, Balázs

    2018-03-01

    Some new dual and mixed variational formulations based on a priori nonsymmetric stresses will be developed for linearly coupled irreversible thermoelastodynamic problems associated with second sound effect according to the Lord-Shulman theory. Having introduced the entropy flux vector instead of the entropy field and defining the dissipation and the relaxation potential as the function of the entropy flux, a seven-field dual and mixed variational formulation will be derived from the complementary Biot-Hamilton-type variational principle, using the Lagrange multiplier method. The momentum-, the displacement- and the infinitesimal rotation vector, and the a priori nonsymmetric stress tensor, the temperature change, the entropy field and its flux vector are considered as the independent field variables of this formulation. In order to handle appropriately the six different groups of temporal prescriptions in the relaxed- and/or the strong form, two variational integrals will be incorporated into the seven-field functional. Then, eliminating the entropy from this formulation through the strong fulfillment of the constitutive relation for the temperature change with the use of the Legendre transformation between the enthalpy and Gibbs potential, a six-field dual and mixed action functional is obtained. As a further development, the elimination of the momentum- and the velocity vector from the six-field principle through the a priori satisfaction of the kinematic equation and the constitutive relation for the momentum vector leads to a five-field variational formulation. These principles are suitable for the transient analyses of the structures exposed to a thermal shock of short temporal domain or a large heat flux.

  17. 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

  18. The Cooling Effect of Urban Parks and Its Monthly Variations in a Snow Climate City

    Directory of Open Access Journals (Sweden)

    Chaobin Yang

    2017-10-01

    Full Text Available Urban parks have been shown to form park cool islands (PCIs, which can effectively alleviate the negative influences of urban heat islands (UHI. However, few studies have examined the detailed characteristics of PCIs, the effect of urban park features on their individual temperatures, and monthly variation in PCIs. Land surface temperature (LST retrieved from Landsat 8 TIR images between May and October were used to represent the thermal environment. Urban park characteristics were extracted from high-resolution GF-2 images. Using these datasets, the relationships between urban park characteristics and PCIs were explored in this study using Changchun, which has a snow climate, as a case study. The results showed the following: (1 the urban parks exhibited a cooling island effect, and the PCIs showed significant monthly variations with the highest intensities in the hot months; (2 the effects of composition (e.g., park size and the percentage of water area on LSTs and PCIs showed significant monthly variability and were stronger than the configuration effects. Furthermore, an unexpected, negative correlation between PCIs and the area of park grass was also found; and (3 larger parks tended to have stronger PCI intensities and extents of influence. For parks larger than 30 ha, the cooling effects extended approximately 480 m from the park edge between June and August. For all of parks during the study duration, the rate of temperature increase was highest within 60 m from the park edge. The PCI we employ specifically in this study is characterized by LST.

  19. 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.

  20. Time variations of fields in superconducting magnets and their effects on accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Herrup, D.A.; Syphers, M.J.; Johnson, D.E.; Johnson, R.P.; Tollestrup, A.V.; Hanft, R.W.; Brown, B.C.; Lamm, M.J.; Kuchnir, M.; McInturff, A.D.

    1988-08-22

    A report on the time dependence of magnetic fields in the superconducting magnets of the Fermilab Tevatron has been published. A field variation of order 1 gauss at the aperture radius is observed. Studies on both full sized Tevatron, dipoles and prototype magnets have been used to elucidate these effects. Explanations based on eddy currents in the coil matrix or on flux creep in the superconducting filaments are explored with these tests. Measurement results and techniques for controlling the effect based on new laboratory tests and the latest accelerator operation are presented. 9 refs., 4 figs.

  1. Time variations of fields in superconducting magnets and their effects on accelerators

    International Nuclear Information System (INIS)

    Herrup, D.A.; Syphers, M.J.; Johnson, D.E.

    1988-01-01

    A report on the time dependence of magnetic fields in the superconducting magnets of the Fermilab Tevatron has been published. A field variation of order 1 gauss at the aperture radius is observed. Studies on both full sized Tevatron, dipoles and prototype magnets have been used to elucidate these effects. Explanations based on eddy currents in the coil matrix or on flux creep in the superconducting filaments are explored with these tests. Measurement results and techniques for controlling the effect based on new laboratory tests and the latest accelerator operation are presented. 9 refs., 4 figs

  2. Length Variation Effect of the Impulse Response Model of a Secondary Path in Embedded Control

    Directory of Open Access Journals (Sweden)

    Young-Sup Lee

    2016-01-01

    Full Text Available This study presents theoretical and experimental investigation on the length variation effect of the impulse response function (IRF for the secondary path model in active noise control using an embedded control board. A narrowband sweep noise was the disturbance for control in a duct with the length of 1800 mm. The IRF model incorporated into an adaptive feedforward filtered-x LMS (FxLMS algorithm was then analyzed in the variation of its length in terms of the mean square error, computation complexity, stability requirement, and attenuation performance before and after control. The FxLMS algorithm with various IRF lengths was implemented in a dSPACE DS1104 embedded control board for the real-time control. Finally the most reasonable IRF length, considering the computation complexity and performance, can be determined through the systematic investigation. The results in this study can be used for practical active noise control systems.

  3. 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.

  4. 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.

  5. Effect of packing fraction variations on reactivity in pebble-bed reactor

    International Nuclear Information System (INIS)

    Snoj, L.; Ravnik, M.

    2004-01-01

    The pebble-bed reactor (PBR) core consists of large number of randomly packed spherical fuel elements. The effect of fuel element packing density variations on multiplication factor in a typical PBR is studied using WIMS code. It is observed that at normal conditions the k-eff increases with packing fraction. Effects of secondary coolant ingress (water or molten lead) in the core at accidental conditions are studied at various packing densities. The effect of water ingress on reactivity depends strongly on water density and packing fraction and is prevailingly positive, while the lead ingress reduces multiplication factor regardless of lead effective density and packing fraction. Both effects are stronger at lower packing fractions. (author)

  6. A comparison of some anatomical characteristics of male and ...

    African Journals Online (AJOL)

    A comparison of some anatomical characteristics of male and female reproductive organs of the white Fulani and west African short horn cattle in Ghana: a ... be due to the confounding effects of the physiological state (follicular or luteal) of the ovaries depending on the oestrus cycle of the cow at the time measurements ...

  7. 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.

  8. 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…

  9. Anatomical and palynological characteristics of Salvia willeana ...

    African Journals Online (AJOL)

    In this study, anatomical and palynological features of the roots, stems, petiole and leaves of Salvia willeana (Holmboe) Hedge and Salvia veneris Hedge, Salvia species endemic to Cyprus, were investigated. In the anatomical characteristics of stem structures, it was found that the chlorenchyma composed of 6 or 7 rows of ...

  10. Morphological and anatomical response of Acacia ehrenbergiana ...

    African Journals Online (AJOL)

    ajl user 3

    2012-02-20

    Feb 20, 2012 ... The response of Acacia ehrenbergiana Hayne and Acacia tortilis (Forssk) Haynes subspp. raddiana seedlings to 100, 50 and 25% field capacity (FC) watering regimes was studied to determine their morphological and anatomical behaviour. Both species responded morphologically as well as anatomically ...

  11. The Effect of Seasonal Weather Variation on the Dynamics of the Plague Disease

    Directory of Open Access Journals (Sweden)

    Rigobert C. Ngeleja

    2017-01-01

    Full Text Available Plague is a historic disease which is also known to be the most devastating disease that ever occurred in human history, caused by gram-negative bacteria known as Yersinia pestis. The disease is mostly affected by variations of weather conditions as it disturbs the normal behavior of main plague disease transmission agents, namely, human beings, rodents, fleas, and pathogens, in the environment. This in turn changes the way they interact with each other and ultimately leads to a periodic transmission of plague disease. In this paper, we formulate a periodic epidemic model system by incorporating seasonal transmission rate in order to study the effect of seasonal weather variation on the dynamics of plague disease. We compute the basic reproduction number of a proposed model. We then use numerical simulation to illustrate the effect of different weather dependent parameters on the basic reproduction number. We are able to deduce that infection rate, progression rates from primary forms of plague disease to more severe forms of plague disease, and the infectious flea abundance affect, to a large extent, the number of bubonic, septicemic, and pneumonic plague infective agents. We recommend that it is more reasonable to consider these factors that have been shown to have a significant effect on RT for effective control strategies.

  12. Incidence and impact: The regional variation of poverty effects due to fossil fuel subsidy reform

    International Nuclear Information System (INIS)

    Rentschler, Jun

    2016-01-01

    Since fossil fuel subsidy reforms can induce significant distributional shifts and price shocks, effective compensation and social protection programs are crucial. Based on the statistical simulation model by Araar and Verme (2012), this study estimates the regional variability of direct welfare effects of removing fuel subsidies in Nigeria. Uncompensated subsidy removal is estimated to increase the national poverty rate by 3–4% on average. However, uniform cash compensation that appears effective at the national average, is found to fail to mitigate price shocks in 16 of 37 states – thus putting livelihoods (and public support for reforms) at risk. States that are estimated to incur the largest welfare shocks, coincide with hotspots of civil unrest following Nigeria's 2012 subsidy reform attempt. The study illustrates how regionally disaggregated compensation can be revenue neutral, and maintain or reduce pre-reform poverty rates in all states. Overall, it highlights the importance of understanding differences in vulnerability, and designing tailored social protection schemes which ensure public support for subsidy reforms. - Highlights: •Fossil fuel subsidy reforms can induce significant distributional shifts and price shocks. •There is significant regional variation of a reform's effects on poverty rates. •Compensation is key to protect livelihoods and win public support for reform. •Compensation schemes must be carefully tailored to account for regional variation.

  13. Effects of variation of hyperfine splitting(structure) in atomic physics

    International Nuclear Information System (INIS)

    Alavi, S A

    2009-01-01

    The possible variation of the fundamental constants is currently a very popular research topic. Theories unifying gravity and other interactions suggest the possibility of spatial and temporal variation of physics constants in the universe. Current interest is high because in superstring theories which have additional dimensions compactified on tiny scales any variation of the size of the extra dimensions results in changes in the 3-dimensional coupling constants. String theory also suggest the space to be noncommutative i.e., the space coordinates do not commute with each other. In this paper we study the hyperfine splitting in the framework of the noncommutative quantum mechanics(NCQM) developed in the literature. We show that the energy difference between two excited F = I + 1/2 and the ground F I - 1/2 states in a noncommutative space(NCS) is bigger than the one in commutative case, so the radiation wavelength in NCS s must be shorter than the radiation wavelength in commutative spaces. We also find an upper bound for the non-commutativity parameter. Since in the very tiny string scale or at very high energy situation the effects of non-commutativity of space may appear so the hyperfine splitting is not constant and changes as energy changes(high energy situation). The results would be of interest both for theoretical and optical spectroscopists.

  14. Variation detection and respondents’ feedback: the cause, effect, and solution of oil spills.

    Directory of Open Access Journals (Sweden)

    Ayodele Sunday Tologbonse

    2018-01-01

    Full Text Available Centred on occurrences of pipeline explosion and oil spills in a host community; a supervised classification technique, of land use/land cover variation detection was carried-out, with Landsat imageries of three time intervals, to determine the percentage of variation between the time intervals. Also carried-out, was a random sampling of questionnaires; dispatch to acquire respondents’ feedback. It addressed respondents’ demographic and social-economic composition of the sample population, the perception on the cause and the impact, and the effect of the oil spill and finally considered the possible solutions. Information was subjected to descriptive analysis and an F-test statistical analysis in a 95% confidence interval. Reports showed that land use/land cover classification had undergone series of percentage variation within the time interval considered, indicating ‘remarks’ of a rise or a decline. While, the measure of insecurity (of about 36.7% is a prevailing element to the unceasing attack on oil pipelines and only a sustaining security measure (of about 40.8% will evidently pave a way-out. Wherefore advocating for community based policing, and a comprehensive technological sensor system, for monitoring of oil pipelines/facilities across the Nation.

  15. 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.

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

    International Nuclear Information System (INIS)

    Syukur, Sumaryati

    2000-01-01

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

  17. Effect of temperature variation on the cytotoxicity of cast dental alloys and commercially pure titanium.

    Science.gov (United States)

    Faria, Adriana Cláudia Lapria; Rodrigues, Renata Cristina Silveira; Antunes, Rossana Pereira de Almeida; de Mattos, Maria da Gloria Chiarello; Rosa, Adalberto Luiz; Ribeiro, Ricardo Faria

    2009-01-01

    Cell culture system has been used to evaluate alloy cytotoxicity under different environments, testing the extracts, but the effect of temperature variation on the cytotoxicity of dental alloys has not been analyzed. The aim of the present study was to investigate if temperature variation could affect dental alloy cytotoxicity, testing alloy extracts in an epithelial cell culture system. Discs of Ni-Cr, Co-Cr-Mo, Ni-Cr-Ti, Ti-6Al-4V and commercially pure titanium (cp Ti) were cast by arc melting, under argon atmosphere, injected by vacuum-pressure. Discs were immersed in artificial saliva and subjected to different temperatures: 37 degrees C and thermocycling (37 degrees C/5 degrees C/37 degrees C/55 degrees C/37 degrees C). After thermocycling, extracts were put in a subconfluent culture during 6 h, and the number of cells and their viability were used to evaluate cytotoxicity in these temperatures. For each alloy, data from temperature conditions were compared by Student's t-test (alpha=0.05). The cytotoxicity tests with alloy/metal extracts showed that Ni-Cr, Co-Cr-Mo, Ti-6Al-4V and cp Ti extracts (p>0.05) did not affect cell number or cell viability, while Ni-Cr-Ti (palloy was subjected to thermocycling. Within the limitations of the present study, the Ni-Cr-Ti alloy had cell number and viability decreased when subjected to temperature variation, while the other alloys/metal extracts did not show these results.

  18. 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. © 2014 European Society of Endocrinology.

  19. 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…

  20. 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.

  1. Effect of variations in rainfall intensity on slope stability in Singapore

    Directory of Open Access Journals (Sweden)

    Christofer Kristo

    2017-12-01

    Full Text Available Numerous scientific evidence has given credence to the true existence and deleterious impacts of climate change. One aspect of climate change is the variations in rainfall patterns, which affect the flux boundary condition across ground surface. A possible disastrous consequence of this change is the occurrence of rainfall-induced slope failures. This paper aims to investigate the variations in rainfall patterns in Singapore and its effect on slope stability. Singapore's historical rainfall data from Seletar and Paya Lebar weather stations for the period of 1985–2009 were obtained and analysed by duration using linear regression. A general increasing trend was observed in both weather stations, with a possible shift to longer duration rainfall events, despite being statistically insignificant according to the Mann-Kendall test. Using the derived trends, projected rainfall intensities in 2050 and 2100 were used in the seepage and slope stability analyses performed on a typical residual soil slope in Singapore. A significant reduction in factor of safety was observed in the next 50 years, with only a marginal decrease in factor of safety in the subsequent 50 years. This indicates a possible detrimental effect of variations in rainfall patterns on slope stability in Singapore, especially in the next 50 years. The statistical analyses on rainfall data from Seletar and Paya Lebar weather stations for the period of 1985–2009 indicated that rainfall intensity tend to increase over the years, with a possible shift to longer duration rainfall events in the future. The stability analyses showed a significant decrease in factor of safety from 2003 to 2050 due to increase in rainfall intensity, suggesting that a climate change might have existed beyond 2009 with possibly detrimental effects to slope stability. Keywords: Climate change, Rainfall, Seepage, Slope stability

  2. 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.

  3. Ultrasound monitoring in cannulation of the internal jugular vein: anatomic and technical considerations.

    Science.gov (United States)

    Docktor, B; So, C B; Saliken, J C; Gray, R R

    1996-06-01

    To examine the effect of variations in anatomic features and operator experience on the success and complication rates of sonographically monitored cannulation of the internal jugular vein. The authors prospectively collected data for ultrasound-monitored cannulation of the internal jugular vein in 150 patients. In all cases the radiologist recorded the side of puncture, the number of passes needed, the number of vein punctures (one or two), whether the walls were opposed during puncture and any complications. For the last 80 patients the following information was also recorded: the distance from the skin to the internal jugular vein, the diameter of the vein with the Valsalva manoeuvre and the location of the vein relative to the carotid artery. All but three of the cannulations were performed by one of three radiologists, all of whom had at least 5 years of experience. Cannulation was successful in all of the patients, and the first pass was successful in 133 (88.7%). These results are better than those of blind placement techniques reported in the literature. The only complications were hematoma and carotid puncture, which both occurred in the same two patients (1.3%). There was no significant difference among the radiologists in the number of passes needed (one-way analysis of variance, p > 0.05). The number of passes was independent of anatomic factors, including depth from skin, vein diameter or relative location. However, significantly more passes were needed for left-side punctures than for right-side punctures (Student t-test, p < 0.05). Real-time ultrasound monitoring is superior to blind techniques in cannulation of the internal jugular vein because of its ease, accuracy and safety. Sonographic real-time monitoring minimizes the impact of anatomic factors on success and complication rates. It is a safe and efficacious approach that should be preferred in the placement of central lines.

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

    DEFF Research Database (Denmark)

    Bundgaard, Peer; Østergaard, Svend

    2007-01-01

    be subject to variations in view of yielding specific meaning effects. This is because the production and reception of a narrative is a dynamic process where physical forces, modal forces and intentions set up a space of possibilities for the narrative trajectory. We therefore propose a determination...... structure is indeed driven by an inverted narrative schema and each significant event in the story but one (as well as each physical paragraph but one) has its rigorously symmetrical counterpart. Moreover, this inverted schema can be explained in terms of the modal forces at stake in the narrative....

  5. 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.

  6. The Effects of Income and Fare Variation on the Demand for Bus Transit Services in Brazil

    OpenAIRE

    Carlos Henrique Ribeiro de Carvalho; Rafael Henrique Moraes Pereira

    2011-01-01

    The public policies on mass transit and other economic policies have been unable to avoid increasing mass transit costs and urban bus fares, which places a burden on a majority of the population depending on public transit. This study analyzes the variations in urban bus fares and households income, as well as their effects on the demand of paying commuters in 9 large Brazilian cities between 1995 and 2008. The study shows that a gap between the rise of urban bus fares and the population`s in...

  7. Genetic variation, inbreeding and chemical exposure—combined effects in wildlife and critical considerations for ecotoxicology

    Science.gov (United States)

    Brown, A. Ross; Hosken, David J.; Balloux, François; Bickley, Lisa K.; LePage, Gareth; Owen, Stewart F.; Hetheridge, Malcolm J.; Tyler, Charles R.

    2009-01-01

    Exposure to environmental chemicals can have negative consequences for wildlife and even cause localized population extinctions. Resistance to chemical stress, however, can evolve and the mechanisms include desensitized target sites, reduced chemical uptake and increased metabolic detoxification and sequestration. Chemical resistance in wildlife populations can also arise independently of exposure and may be spread by gene flow between populations. Inbreeding—matings between closely related individuals—can have negative fitness consequences for natural populations, and there is evidence of inbreeding depression in many wildlife populations. In some cases, reduced fitness in inbred populations has been shown to be exacerbated under chemical stress. In chemical testing, both inbred and outbred laboratory animals are used and for human safety assessments, iso-genic strains (virtual clones) of mice and rats are often employed that reduce response variation, the number of animals used and associated costs. In contrast, for environmental risk assessment, strains of animals are often used that have been selectively bred to maintain heterozygosity, with the assumption that they are better able to predict adverse effects in wild, genetically variable, animals. This may not necessarily be the case however, as one outbred strain may not be representative of another or of a wild population. In this paper, we critically discuss relationships between genetic variation, inbreeding and chemical effects with the intention of seeking to support more effective chemical testing for the protection of wildlife. PMID:19833649

  8. A STUDY ON THE EFFECTS OF VIEWING ANGLE VARIATION IN SUGARCANE RADIOMETRIC MEASURES

    Directory of Open Access Journals (Sweden)

    Érika Akemi Saito; Moriya

    Full Text Available Abstract: Remote Sensing techniques, such as field spectroscopy provide information with a large level of detail about spectral characteristics of plants enabling the monitoring of crops. The aim of this study is to analyze the influence of viewing angle in estimating the Bidirectional Reflectance Distribution Function (BRDF for the case of sugarcane. The study on the variation of the spectral reflectance profile can help the improvement of algorithms for correction of BRDF in remote sensing images. Therefore, spectral measurements acquired on nadir and different off-nadir view angle directions were considered in the experiments. Change both anisotropy factor and anisotropy index was determined in order to evaluate the BRDF variability in the spectral data of sugarcane. BRDF correction was applied using the Walthall model, thus reducing the BRDF effects. From the results obtained in the experiments, the spectral signatures showed a similar spectral pattern varying mainly in intensity. The anisotropy factor which showed a similar pattern in all wavelengths. The visual analysis of the spectral reflectance profile of sugarcane showed variation mainly in intensity at different angles. The use of Walthall model reduced the BRDF effects and brought the spectral reflectance profiles acquired on different viewing geometry close to nadir viewing. Therefore, BRDF effects on remote sensing data of vegetation cover can be minimized by applying this model. This conclusion contributes to developing suitable algorithms to produce radiometrically calibrated mosaics with remote sensing images taken by aerial platforms.

  9. 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. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Determination of the variation of mercury isotope concentration based on spectral-phase effects

    International Nuclear Information System (INIS)

    Ganeev, A.A.; Man', D.D.; Turkin, Yu.I.

    1988-01-01

    A method of isotopic atomic-absorption analysis, based on spectral-phase effects in which there is no need to use several sources of radiation with pure isotopes of the analyte element, was developed. The method made it possible to simplify the analysis and to determine the variation of the concentration of mercury isotopes from one deposit to another with an accuracy several times higher that of traditional methods of spectral isotopic analysis. The method was tested on mercury 198 and mercury 202. The isotopic analyzer is diagramed and described. The mechanism of spectral-phase effects was determined by the difference in effective photon lifetimes, corresponding to different components of the hyperfine structure of the resonance line of mercury at 254 nm

  11. 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

  12. The effects of variations in nuclear interactions on nucleosynthesis in thermonuclear supernovae

    Science.gov (United States)

    Parikh, A.; José, J.; Seitenzahl, I. R.; Röpke, F. K.

    2013-09-01

    of reactions would, however, help to further constrain model predictions. In addition, we confirm the need for a detailed, consistent treatment of all relevant stellar weak interaction rates since simultaneous variation of these rates (as opposed to individual variation) has a significant effect on yields in our models.

  13. Effects of Seasonal Variations on the Outcome of Coronary Artery Bypass Graft Surgery

    Directory of Open Access Journals (Sweden)

    Mohammad Hassan Nemati

    2013-06-01

    Full Text Available Background: For all the reports on the association between seasons and coronary artery disease, there is a paucity of information on the possible effects of seasonal variations on the outcome of patients after coronary artery bypass grafting surgery (CABG. The aim of this study was to assess the short-term outcome of post-CABG patients in the four different seasons to find any correlation between seasonal variations and the outcome of such patients. Methods: Data on patients who underwent cardiac surgery between 2007 and 2009 were analyzed. In-hospital mortality, length of Intensive Care Unit (ICU stay, and length of hospital stay in the four different seasons were considered as outcome measures. The EuroSCORE was calculated for all the patients, and the Kruskal-Wallis, Mann-Whitney, Student t, and chi square tests were used as appropriate. Results: Of a total of 402 patients, who underwent CABG during the mentioned period, 292 patients were male (M/F ratio=2.65. There were no differences in terms of mean age, sex ratio, and mean EuroSCORE of the patients between the seasons. The mean length of ICU stay was significantly more in the spring than that of the other seasons (P<0.001, while the difference between the four seasons regarding the mean length of hospital stay did not constitute statistical significance (P=0.22. No effect of seasonal variations was found for the lengths of ICU and hospital stay in the presence of the EuroSCORE after multiple logistic regression analysis (P=0.278, 0.431.Conclusion: Psychological mood changes caused by regional cultural differences rather than environmental factors should be considered in the optimal management of patients after CABG.

  14. Effects of technique variations on knee biomechanics during the squat and leg press.

    Science.gov (United States)

    Escamilla, R F; Fleisig, G S; Zheng, N; Lander, J E; Barrentine, S W; Andrews, J R; Bergemann, B W; Moorman, C T

    2001-09-01

    The specific aim of this project was to quantify knee forces and muscle activity while performing squat and leg press exercises with technique variations. Ten experienced male lifters performed the squat, a high foot placement leg press (LPH), and a low foot placement leg press (LPL) employing a wide stance (WS), narrow stance (NS), and two foot angle positions (feet straight and feet turned out 30 degrees ). No differences were found in muscle activity or knee forces between foot angle variations. The squat generated greater quadriceps and hamstrings activity than the LPH and LPL, the WS-LPH generated greater hamstrings activity than the NS-LPH, whereas the NS squat produced greater gastrocnemius activity than the WS squat. No ACL forces were produced for any exercise variation. Tibiofemoral (TF) compressive forces, PCL tensile forces, and patellofemoral (PF) compressive forces were generally greater in the squat than the LPH and LPL, and there were no differences in knee forces between the LPH and LPL. For all exercises, the WS generated greater PCL tensile forces than the NS, the NS produced greater TF and PF compressive forces than the WS during the LPH and LPL, whereas the WS generated greater TF and PF compressive forces than the NS during the squat. For all exercises, muscle activity and knee forces were generally greater in the knee extending phase than the knee flexing phase. The greater muscle activity and knee forces in the squat compared with the LPL and LPH implies the squat may be more effective in muscle development but should be used cautiously in those with PCL and PF disorders, especially at greater knee flexion angles. Because all forces increased with knee flexion, training within the functional 0-50 degrees range may be efficacious for those whose goal is to minimize knee forces. The lack of ACL forces implies that all exercises may be effective during ACL rehabilitation.

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

    Directory of Open Access Journals (Sweden)

    Berliet Assad Gomes

    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.

  16. Effective Area and Various Variations of The Northern Polar Cap Magnetic Activity Index (pcn)

    Science.gov (United States)

    Gromova, L.; Papitashvili, O.; Popov, V.; Rasmussen, O.

    We investigated the effective area and various variations (universal time, seasonal, and solar cycle) from the PCN time series available since 1975 and derived from cor- relation analyses of ground geomagnetic observations at Qaanaaq (Thule, Greenland) with the "merging" interplanetary electric field. We analyzed solar cycle variations in the normalization coefficients (slope and intercept) and preferred direction of the transpolar ionospheric current (all used for routine calculations of PCN) from 1964 to 1999 combining data monthly for three consecutive years and using a 3-year box- car sliding window. The obtained results show that the solar cycle effect is clearly seen in the studied parameters amounting to 25% of the magnitude change during winter and equinox but increasing to 40% during summer. We calculated similar sets of coefficients and the index for all high-latitude Greenlandic stations, Nord and Resolute Bay stations using data from 1991 to 1999 by the 3-year sliding window. It is concluded that (even a set of normalization coefficients is obtained for a specific station) the "station-based" PC-indices are almost identical only for two most north- ern observatories Thule (THL) and Savissivik (SVS) through an entire UT day; other stations located at lower latitudes produce the index similar to THL and SVS only during few nighttime hours. Thus, we firmly justified that the area where the Northern PC index stably preserves a value is located within 7 distance from the northern geomagnetic pole.

  17. 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.

  18. Effects of environmental factors and appendage injury on the wing variation in the cricket Velarifictorus ornatus

    Science.gov (United States)

    Zhao, Lü-Quan; Zhu, Dao-Hong

    2014-01-01

    Abstract The effects of environmental factors and appendage injury on the wing variation in Velarifictorus ornatus (Shiraki) (Orthoptera: Gryllidae) were investigated. The percentage of micropters was more than 95% when the nymphs were reared at constant photoperiods, and changing photoperiod did not affect wing variation in V. ornatus at 25 or 30°C. In the crowding experiment, the percentage of macropters was only 11.2% when the nymphs were reared separately at 25°C. In contrast, the percentage of macropters was significantly higher when the rearing density was increased to two nymphs per container and lower when the rearing density was increased to five or 10 nymphs per container. These results indicate that low and high rearing densities induce micropters, but intermediate rearing density stimulates the formation of macropters. Meanwhile, severance of appendages, such as antennae, femora, and tibiae, in the nymph stage exerted a micropterizing effect. The period sensitive to such stresses ranged from 35 to 60 days of nymph development. PMID:25368061

  19. Effects of environmental factors and appendage injury on the wing variation in the cricket Velarifictorus ornatus.

    Science.gov (United States)

    Zhao, Lü-Quan; Zhu, Dao-Hong

    2014-01-01

    The effects of environmental factors and appendage injury on the wing variation in Velarifictorus ornatus (Shiraki) (Orthoptera: Gryllidae) were investigated. The percentage of micropters was more than 95% when the nymphs were reared at constant photoperiods, and changing photoperiod did not affect wing variation in V. ornatus at 25 or 30°C. In the crowding experiment, the percentage of macropters was only 11.2% when the nymphs were reared separately at 25°C. In contrast, the percentage of macropters was significantly higher when the rearing density was increased to two nymphs per container and lower when the rearing density was increased to five or 10 nymphs per container. These results indicate that low and high rearing densities induce micropters, but intermediate rearing density stimulates the formation of macropters. Meanwhile, severance of appendages, such as antennae, femora, and tibiae, in the nymph stage exerted a micropterizing effect. The period sensitive to such stresses ranged from 35 to 60 days of nymph development. This is an open access paper. We use the Creative Commons Attribution 3.0 license that permits unrestricted use, provided that the paper is properly attributed.

  20. The Effects of Structural Parameter Variation on Cable Force of Fast Cable-Net Structure

    Directory of Open Access Journals (Sweden)

    Qiming Wang

    2014-02-01

    Full Text Available Five-hundred-meter aperture spherical radio telescope (FAST is supported by a cable-net structure, which enables its surface to form a real-time paraboloid by active control. FAST project is currently in the construction and implementation stage. However, there are always a considerable amount of errors that existed in practice which may result in the deviation of the structure from its ideal model or design. Therefore, structural parameter sensitivity analysis was discussed, which is indispensable. However, such deformation operation would lead to about 500 MPa of fatigue stress variation amplitude in the cable-net structure. Optimized deformation strategy is proposed to release the fatigue stress of the cable-net structure, which would be of advantage to improve the reliability of the cable-net structure. In the paper, the variation ranges of structural parameters were rationally determined. Based on local sensitivity analysis and global sensitivity analysis method, finite element model was used to study the effect of different structural parameters on the static behavior. It can be concluded that the effect of several key design parameters such as the cutting length and the elastic modulus of cable on the cable force is significant. The global sensitivity analysis indicates that the cable force range of the cable-net is −19% to 27%.

  1. Differential effects of ADORA2A gene variations in pre-attentive visual sensory memory subprocesses.

    Science.gov (United States)

    Beste, Christian; Stock, Ann-Kathrin; Ness, Vanessa; Epplen, Jörg T; Arning, Larissa

    2012-08-01

    The ADORA2A gene encodes the adenosine A(2A) receptor that is highly expressed in the striatum where it plays a role in modulating glutamatergic and dopaminergic transmission. Glutamatergic signaling has been suggested to play a pivotal role in cognitive functions related to the pre-attentive processing of external stimuli. Yet, the precise molecular mechanism of these processes is poorly understood. Therefore, we aimed to investigate whether ADORA2A gene variation has modulating effects on visual pre-attentive sensory memory processing. Studying two polymorphisms, rs5751876 and rs2298383, in 199 healthy control subjects who performed a partial-report paradigm, we find that ADORA2A variation is associated with differences in the efficiency of pre-attentive sensory memory sub-processes. We show that especially the initial visual availability of stimulus information is rendered more efficiently in the homozygous rare genotype groups. Processes related to the transfer of information into working memory and the duration of visual sensory (iconic) memory are compromised in the homozygous rare genotype groups. Our results show a differential genotype-dependent modulation of pre-attentive sensory memory sub-processes. Hence, we assume that this modulation may be due to differential effects of increased adenosine A(2A) receptor signaling on glutamatergic transmission and striatal medium spiny neuron (MSN) interaction. Copyright © 2011 Elsevier B.V. and ECNP. All rights reserved.

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

    International Nuclear Information System (INIS)

    Fingas, M.

    2005-01-01

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

  3. Estimation and Compensation of Process Induced Variations in Nanoscale Tunnel Field Effect Transistors (TFETs) for Improved Reliability

    OpenAIRE

    Saurabh, Sneh; Kumar, M. Jagadesh

    2010-01-01

    Tunnel Field Effect Transistors (TFET) have extremely low leakage current, exhibit excellent subthreshold swing and are less susceptible to short channel effects. However, TFETs do face certain special challenges, particularly with respect to the process induced variations in (i) the channel length and (ii) the thickness of the silicon thin-film and the gate oxide. This paper, for the first time, studies the impact of the above process variations on the electrical characteristics of a Double ...

  4. GIDL analysis of the process variation effect in gate-all-around nanowire FET

    Science.gov (United States)

    Kim, Shinkeun; Seo, Youngsoo; Lee, Jangkyu; Kang, Myounggon; Shin, Hyungcheol

    2018-02-01

    In this paper, the gate-induced drain leakage (GIDL) is analyzed on gate-all-around (GAA) Nanowire FET (NW FET) with ellipse-shaped channel induced by process variation effect (PVE). The fabrication process of nanowire can lead to change the shape of channel cross section from circle to ellipse. The effect of distorted channel shape is investigated and verified by technology computer-aided design (TCAD) simulation in terms of the GIDL current. The simulation results demonstrate that the components of GIDL current are two mechanisms of longitudinal band-to-band tunneling (L-BTBT) at body/drain junction and transverse band-to-band tunneling (T-BTBT) at gate/drain junction. These two mechanisms are investigated on channel radius (rnw) and aspect ratio of ellipse-shape respectively and together.

  5. Effect of fuel particles' size variations on multiplication factor in pebble-bed nuclear reactor

    International Nuclear Information System (INIS)

    Snoj, L.; Ravnik, M.

    2005-01-01

    The pebble-bed reactor (Pbr) spherical fuel element consists of two radial zones: the inner zone, in which the fissile material in form of the so-called TRISO particles is uniformly dispersed in graphite matrix and the outer zone, a shell of pure graphite. A TRISO particle is composed of a fissile kernel (UO 2 ) and several layers of carbon composites. The effect of TRISO particles' size variations and distance between them on PBR multiplication factor is studied using MCNP code. Fuel element is modelled in approximation of a cubical unit cell with periodic boundary condition. The multiplication factor of the fuel element depends on the size of the TRISO particles due to resonance self-shielding effect and on the inter-particle distance due to inter-kernel shadowing. (author)

  6. Length-scale effect due to periodic variation of geometrically necessary dislocation densities

    DEFF Research Database (Denmark)

    Oztop, M. S.; Niordson, Christian Frithiof; Kysar, J. W.

    2013-01-01

    Strain gradient plasticity theories have been successful in predicting qualitative aspects of the length scale effect, most notably the increase in yield strength and hardness as the size of the deforming volume decreases. However new experimental methodologies enabled by recent developments...... the microstructure of deformed metals in addition to the size effect. Recent GND measurements have revealed a distribution of length scales that evolves within a metal undergoing plastic deformation. Furthermore, these experiments have shown an accumulation of GND densities in cell walls as well as a variation...... of the saturation value of dislocation densities in these cell walls and dislocation structures. In this study, a strain gradient plasticity framework is extended by incorporating the physical quantities obtained from experimental observations: the quasi-periodicity and the saturation value of GND densities...

  7. The effects of mantle and anelasticity on nutations, earth tides, and tidal variations in rotation rate

    Science.gov (United States)

    Wahr, John; Bergen, Zachary

    1986-01-01

    The paper models the effects of mantle anelasticity on luni-solar nutations, on tidal deformation, on tidal variations in rotation rate, and on the eigenfrequency of the free core nutation. The results can be used to invert observations to solve for the anelastic contributions to the shear and bulk moduli of the upper and lower mantle. Specific anelastic models are used to numerically estimate the effects of anelasticity on these geodetic observables. The nutation estimates are compared with observational results. Among the conclusions: (1) mantle anelasticity is likely to be the most important source of damping for the free core nutation; (2) present VLBI nutation results are, in principle, accurate enough to usefully bound anelasticity at diurnal periods. But the discrepancy between the VLBI observed nutations and the 1984 IAU nutation model cannot be explained by anelasticity and is not yet well enough understood to allow anelasticity to be determined from the data.

  8. Anatomical Position of Mental foramen: a Review

    Directory of Open Access Journals (Sweden)

    Vinit Aher

    2012-01-01

    Full Text Available Mental foramen is a key factor in many of the surgical as well as clinical procedures in routine clinical practice. The variations of mental foramen with respect to position, size and number dose significantly alter the clinical implications of various intraoral treatments. The accurate knowledge of the mental nerve and its position helps the clinician for delivering local anesthesia effectively also placement of implants and dentures intraorally to replace missing teeth is important in prosthetic point of view. While doing the surgical procedures in this region the position of mental nerve and its foramen is of importance to avoid intraoperative neurovascular damage and to avoid postoperative neurosensory disturbances. The ethnic and racial variations are seen in the position of mental foramen, although a gender variation in same population has not been seen. Thus the knowledge of the position of mental nerve is important for day to day clinical practice of dentistry.

  9. Effect of temperature variation on the cytotoxicity of cast dental alloys and commercially pure titanium

    Directory of Open Access Journals (Sweden)

    Adriana Cláudia Lapria Faria

    2009-10-01

    Full Text Available Cell culture system has been used to evaluate alloy cytotoxicity under different environments, testing the extracts, but the effect of temperature variation on the cytotoxicity of dental alloys has not been analyzed. OBJECTIVE: The aim of the present study was to investigate if temperature variation could affect dental alloy cytotoxicity, testing alloy extracts in an epithelial cell culture system. MATERIAL AND METHODS: Discs of Ni-Cr, Co-Cr-Mo, Ni-Cr-Ti, Ti-6Al-4V and commercially pure titanium (cp Ti were cast by arc melting, under argon atmosphere, injected by vacuum-pressure. Discs were immersed in artificial saliva and subjected to different temperatures: 37ºC and thermocycling (37ºC/5ºC/37ºC/55ºC/37ºC. After thermocycling, extracts were put in a subconfluent culture during 6 h, and the number of cells and their viability were used to evaluate cytotoxicity in these temperatures. For each alloy, data from temperature conditions were compared by Student's t-test (α=0.05. RESULTS: The cytotoxicity tests with alloy/metal extracts showed that Ni-Cr, Co-Cr-Mo, Ti-6Al-4V and cp Ti extracts (p>0.05 did not affect cell number or cell viability, while Ni-Cr-Ti (p<0.05 extract decreased cell number and viability when the alloy was subjected to thermocycling. CONCLUSION: Within the limitations of the present study, the Ni-Cr-Ti alloy had cell number and viability decreased when subjected to temperature variation, while the other alloys/metal extracts did not show these results.

  10. Effectiveness of biodiversity surrogates for conservation planning: different measures of effectiveness generate a kaleidoscope of variation.

    Science.gov (United States)

    Grantham, Hedley S; Pressey, Robert L; Wells, Jessie A; Beattie, Andrew J

    2010-07-14

    Conservation planners represent many aspects of biodiversity by using surrogates with spatial distributions readily observed or quantified, but tests of their effectiveness have produced varied and conflicting results. We identified four factors likely to have a strong influence on the apparent effectiveness of surrogates: (1) the choice of surrogate; (2) differences among study regions, which might be large and unquantified (3) the test method, that is, how effectiveness is quantified, and (4) the test features that the surrogates are intended to represent. Analysis of an unusually rich dataset enabled us, for the first time, to disentangle these factors and to compare their individual and interacting influences. Using two data-rich regions, we estimated effectiveness using five alternative methods: two forms of incidental representation, two forms of species accumulation index and irreplaceability correlation, to assess the performance of 'forest ecosystems' and 'environmental units' as surrogates for six groups of threatened species-the test features-mammals, birds, reptiles, frogs, plants and all of these combined. Four methods tested the effectiveness of the surrogates by selecting areas for conservation of the surrogates then estimating how effective those areas were at representing test features. One method measured the spatial match between conservation priorities for surrogates and test features. For methods that selected conservation areas, we measured effectiveness using two analytical approaches: (1) when representation targets for the surrogates were achieved (incidental representation), or (2) progressively as areas were selected (species accumulation index). We estimated the spatial correlation of conservation priorities using an index known as summed irreplaceability. In general, the effectiveness of surrogates for our taxa (mostly threatened species) was low, although environmental units tended to be more effective than forest ecosystems. The

  11. 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

  12. The Effect of EHR System Setting on Fuel Consumption and Tractor Engine Speed Variation

    Directory of Open Access Journals (Sweden)

    Dušan Slimařík

    2015-01-01

    Full Text Available The work is aimed on possibilities of fuel consumption reduction via EHR system setting with the influence on tractor engine speed variation. During tractor utilization in agricultural applications fuel consumption is measured and evaluated. The main objective of this text is fuel consumption reduction verification. Firstly, article describes tractor engine parameters acquirement. Complete engine characteristic is obtained from laboratory experiments. This was essential step for lowest fuel consumption area detecting. Next, the principle of EHR system function is clarified. Then connection between complete engine characteristic and EHR system setting interaction is mentioned and the aim of field measurement is set. Another part is devoted to field measurement conditions and EHR system setting. This part is essential for the possibility of field measurement re-examination. Deep plowing with John Deere 6920S and Lemken Vari Diamant 10 was realized. The EHR various settings were examined and their effect on tractor engine speed variation was observed. The results show possibility of fuel consumption reduction. The properly chosen aggregation of tractor power and plough type with correct electro-hydraulic system setting brings fuel consumption reduction. This conclusion may be used for fuel savings in global scale for better economic utilization of tractor.

  13. Effects of arterial load variations on dynamic arterial elastance: an experimental study.

    Science.gov (United States)

    Monge García, M I; Guijo González, P; Gracia Romero, M; Gil Cano, A; Rhodes, A; Grounds, R M; Cecconi, M

    2017-06-01

    Dynamic arterial elastance (Ea dyn ), the relationship between pulse pressure variation (PPV) and stroke volume variation (SVV), has been suggested as a functional assessment of arterial load. The aim of this study was to evaluate the impact of arterial load changes during acute pharmacological changes, fluid administration, and haemorrhage on Ea dyn . Eighteen anaesthetized, mechanically ventilated New Zealand rabbits were studied. Arterial load changes were induced by phenylephrine ( n =9) or nitroprusside ( n =9). Thereafter, animals received a fluid bolus (10 ml kg -1 ), followed by stepwise bleeding (blood loss: 15 ml kg -1 ). The influence of arterial load and cardiac variables on PPV, SVV, and Ea dyn was analysed using a linear mixed-effects model analysis. After phenylephrine infusion, mean ( sd ) Ea dyn decreased from 0.89 (0.14) to 0.49 (0.12), P load induced significant changes on Ea dyn ; vasodilatation increased Ea dyn , whereas vasoconstriction decreased it. The Ea dyn was associated with both arterial load and cardiac factors, suggesting that Ea dyn should be more properly considered as a ventriculo-arterial coupling index. © The Author 2017. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  14. Microwave thermal ablation: Effects of tissue properties variations on predictive models for treatment planning.

    Science.gov (United States)

    Lopresto, Vanni; Pinto, Rosanna; Farina, Laura; Cavagnaro, Marta

    2017-08-01

    Microwave thermal ablation (MTA) therapy for cancer treatments relies on the absorption of electromagnetic energy at microwave frequencies to induce a very high and localized temperature increase, which causes an irreversible thermal damage in the target zone. Treatment planning in MTA is based on experimental observations of ablation zones in ex vivo tissue, while predicting the treatment outcomes could be greatly improved by reliable numerical models. In this work, a fully dynamical simulation model is exploited to look at effects of temperature-dependent variations in the dielectric and thermal properties of the targeted tissue on the prediction of the temperature increase and the extension of the thermally coagulated zone. In particular, the influence of measurement uncertainty of tissue parameters on the numerical results is investigated. Numerical data were compared with data from MTA experiments performed on ex vivo bovine liver tissue at 2.45GHz, with a power of 60W applied for 10min. By including in the simulation model an uncertainty budget (CI=95%) of ±25% in the properties of the tissue due to inaccuracy of measurements, numerical results were achieved in the range of experimental data. Obtained results also showed that the specific heat especially influences the extension of the thermally coagulated zone, with an increase of 27% in length and 7% in diameter when a variation of -25% is considered with respect to the value of the reference simulation model. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.

  15. Effect of abattoir and cut on variations in microbial communities of vacuum-packaged beef.

    Science.gov (United States)

    Kaur, Mandeep; Bowman, John P; Porteus, Bianca; Dann, Alison L; Tamplin, Mark

    2017-09-01

    This report builds on the earlier studies of the shelf-life of chilled Australian vacuum packaged (VP) beef primals (striploin and cube roll), products distinguished in the global marketplace for unusually long shelf-life. Notable findings in those studies were a shelf-life of at least 26weeks at -0.5°C, low microbial counts, and relatively high sensory scores. However, growth rates for total viable counts (TVC) and lactic acid bacteria (LAB) varied among the different abattoirs. The present study adds to these findings, by providing greater definition about temporal changes in bacterial communities using terminal restriction fragment length polymorphism (TRFLP) and clone library analyses of 16S ribosomal RNA (16S rRNA) gene, and measuring statistical associations among abattoir, beef cut, storage time and sensory attributes. Bacterial communities changed over time, with Carnobacterium spp. typically predominating (29-97%) at the end of storage. Variation in TRFLP profiles showed that different Carnobacterium strains predominated in different abattoirs, and that additional variation was due to the presence of other taxa typical of VP meat microbiomes. TRFLP-based community structure correlated significantly (P≤0.01) with sensorial characteristics, such as vacuum integrity, confinement odour, and intact pack appearance of beef. This study shows that Carnobacterium spp. predominate on extended shelf-life VP beef primals, while other taxa may produce subtle effects on shelf-life duration. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. 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.

  17. 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.

  18. Juvenile survival in a tropical population of roseate terns: Interannual variation and effect of tick parasitism

    Science.gov (United States)

    Monticelli, David; Ramos, Jaime A.; Hines, James E.; Nichols, James D.; Spendelow, Jeffrey A.

    2008-01-01

    Many demographic studies on long-lived seabirds have focused on the estimation of adult survival, but much less is known about survival during the early years of life, especially in tropical species. We report analyses of a capture–recapture dataset of 685 roseate terns ringed as fledglings and adults between 1998 and 2005 on Aride Island, Seychelles, and recaptured/resighted at the same colony site over a 5 yr (2002 to 2006) period. A multistate model was used to estimate survival for different age classes, including juvenile (first-year) birds returning as non-breeding prospectors. The effect of infestation by parasites (ticks) on survival was also examined. Overall, the estimated return of first-year individuals to the natal colony was very variable, ranging from 2 to 22%. Conditioned on survival, the probability of returning from Age 2 yr onwards increased to 70%. Survival rates were best modeled as time-specific, with estimates varying from 0.02 to 1.00 (mean 0.69) in first-year birds with a marked negative effect of tick infestation. In older birds (minimum age of 2 yr), the annual estimates fell between 0.69 and 0.86 (mean 0.77). Using a components of variance approach for estimation of year-to-year variation, we found high temporal variability for first-year individuals (coefficient of variation [CV] = 65%) compared to much less variation in the survival rate of older birds (CV = 9%). These findings agree with the life-history prediction that demographic rates of juveniles are usually lower and more variable than those of older individuals. Our results are also consistent with the predicted negative effect of tick parasitism on juvenile survival. Compared with data from other roseate tern populations, survival over the first 2 yr (Age 0 to 2 yr) was 18 to 40% higher in this study, suggesting that a high ‘young’ survival rate may be an important demographic trait in this tropical population to compensate for the low annual reproductive success. Our

  19. 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

  20. Clinical repercussions of Martin-Gruber anastomosis: anatomical study

    Directory of Open Access Journals (Sweden)

    Cristina Schmitt Cavalheiro

    2016-04-01

    Full Text Available 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.

  1. Intersection syndrome: MR imaging with anatomic comparison of the distal forearm

    International Nuclear Information System (INIS)

    Lima, Jose E. de; Kim, Hyun-Jin; Albertotti, Flavio; Resnick, Donald

    2004-01-01

    To correlate the anatomic and MR imaging characteristics of the area of intersection of the first and the second dorsal extensor tendon compartments (DETC) in the distal forearm in an attempt to improve the design of MR imaging protocols used for the evaluation of intersection syndrome. Ten forearms of nine cadavers underwent MR imaging in the axial and sagittal-oblique planes before and after tenography with direct injection of a gadolinium-containing contrast agent into the first DETC in four forearms, the second DETC in four forearms, and both compartments in the remaining two forearms. The area of intersection between the first and second DETC was identified in each case as well as its distance from Lister's tubercle. Subsequently all forearms were sectioned in the axial (8 forearms) or sagittal-oblique planes (2 remaining forearms) to parallel the imaging planes. Detailed examination of each of the anatomic slices was performed in a search for anatomic variations and for possible anatomic connections of the tendons sheaths. One forearm was dissected to identify the area of intersection. The area of intersection between the first and second DETC occurred between 3.5 cm and 4.8 cm (mean 4.18 cm) proximal to Lister's tubercle. After tenography, gadolinium solution was noted in the third DETC in two of four specimens in which the second DETC was injected and in one of two specimens in which both the first and second DETC were injected. Extension of the gadolinium solution between the first and second DETC was noted during isolated injections of either compartment, although this finding may have related to iatrogenic injection effects. The axial plane was the most valuable for assessment of the area of intersection of the first and second DETC. MR imaging is a noninvasive method that can be used for the evaluation of distal forearm and wrist pain. Standard wrist protocols do not include the area of intersection between the first and second DETC and, in those cases

  2. Intersection syndrome: MR imaging with anatomic comparison of the distal forearm

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Jose E. de; Kim, Hyun-Jin; Albertotti, Flavio; Resnick, Donald [University of California, San Diego, VA San Diego Healthcare System, San Diego (United States)

    2004-11-01

    To correlate the anatomic and MR imaging characteristics of the area of intersection of the first and the second dorsal extensor tendon compartments (DETC) in the distal forearm in an attempt to improve the design of MR imaging protocols used for the evaluation of intersection syndrome. Ten forearms of nine cadavers underwent MR imaging in the axial and sagittal-oblique planes before and after tenography with direct injection of a gadolinium-containing contrast agent into the first DETC in four forearms, the second DETC in four forearms, and both compartments in the remaining two forearms. The area of intersection between the first and second DETC was identified in each case as well as its distance from Lister's tubercle. Subsequently all forearms were sectioned in the axial (8 forearms) or sagittal-oblique planes (2 remaining forearms) to parallel the imaging planes. Detailed examination of each of the anatomic slices was performed in a search for anatomic variations and for possible anatomic connections of the tendons sheaths. One forearm was dissected to identify the area of intersection. The area of intersection between the first and second DETC occurred between 3.5 cm and 4.8 cm (mean 4.18 cm) proximal to Lister's tubercle. After tenography, gadolinium solution was noted in the third DETC in two of four specimens in which the second DETC was injected and in one of two specimens in which both the first and second DETC were injected. Extension of the gadolinium solution between the first and second DETC was noted during isolated injections of either compartment, although this finding may have related to iatrogenic injection effects. The axial plane was the most valuable for assessment of the area of intersection of the first and second DETC. MR imaging is a noninvasive method that can be used for the evaluation of distal forearm and wrist pain. Standard wrist protocols do not include the area of intersection between the first and second DETC and, in

  3. 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.

  4. 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…

  5. 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.

  6. Environmental variation alters the fitness effects of rifampicin resistance mutations in Pseudomonas aeruginosa.

    Science.gov (United States)

    Gifford, Danna R; Moss, Ethan; MacLean, R Craig

    2016-03-01

    The fitness effects of antibiotic resistance mutations in antibiotic-free conditions play a key role in determining the long-term maintenance of resistance. Although resistance is usually associated with a cost, the impact of environmental variation on the cost of resistance is poorly understood. Here, we test the impact of heterogeneity in temperature and resource availability on the fitness effects of antibiotic resistance using strains of the pathogenic bacterium Pseudomonas aeruginosa carrying clinically important rifampicin resistance mutations. Although the rank order of fitness was generally maintained across environments, fitness effects relative to the wild type differed significantly. Changes in temperature had a profound impact on the fitness effects of resistance, whereas changes in carbon substrate had only a weak impact. This suggests that environmental heterogeneity may influence whether the costs of resistance are likely to be ameliorated by second-site compensatory mutations or by reversion to wild-type rpoB. Our results highlight the need to consider environmental heterogeneity and genotype-by-environment interactions for fitness in models of resistance evolution. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

  7. Brief communication: human cranial variation fits iterative founder effect model with African origin.

    Science.gov (United States)

    von Cramon-Taubadel, Noreen; Lycett, Stephen J

    2008-05-01

    Recent studies comparing craniometric and neutral genetic affinity matrices have concluded that, on average, human cranial variation fits a model of neutral expectation. While human craniometric and genetic data fit a model of isolation by geographic distance, it is not yet clear whether this is due to geographically mediated gene flow or human dispersal events. Recently, human genetic data have been shown to fit an iterative founder effect model of dispersal with an African origin, in line with the out-of-Africa replacement model for modern human origins, and Manica et al. (Nature 448 (2007) 346-349) have demonstrated that human craniometric data also fit this model. However, in contrast with the neutral model of cranial evolution suggested by previous studies, Manica et al. (2007) made the a priori assumption that cranial form has been subject to climatically driven natural selection and therefore correct for climate prior to conducting their analyses. Here we employ a modified theoretical and methodological approach to test whether human cranial variability fits the iterative founder effect model. In contrast with Manica et al. (2007) we employ size-adjusted craniometric variables, since climatic factors such as temperature have been shown to correlate with aspects of cranial size. Despite these differences, we obtain similar results to those of Manica et al. (2007), with up to 26% of global within-population craniometric variation being explained by geographic distance from sub-Saharan Africa. Comparative analyses using non-African origins do not yield significant results. The implications of these results are discussed in the light of the modern human origins debate. (c) 2007 Wiley-Liss, Inc.

  8. Variation in direct and maternal genetic effects for meat production traits in Egyptian Zaraibi goats.

    Science.gov (United States)

    Shaat, I; Mäki-Tanila, A

    2009-06-01

    Multi-trait analyses were carried out to quantify the (co)variation in meat production traits in Zaraibi goats. The data were obtained from a research station. There were birth weight records on 6610 kids, of which 5970 and 5237 had also pre-and postweaning gain record, respectively. The kids were progeny of 115 bucks and 1387 does, which had altogether 3603 litter size and milk yield records in different parities and which were daughters of 109 sires and 721 dams. Single-trait analyses were carried out as preliminary to a three-trait (litter size, birth weight, early growth) and five-trait (litter size, milk and growth traits) analyses. The analyses containing birth weight data required the highest number of iteration rounds in estimating the variance components using AI REML. The maternal genetic component was important for the genetic variation of birth weight and preweaning gain. In general, direct heritability was low (0.03-0.12) for growth traits, possibly due to the low-input environment. The estimates on genetic correlation between direct and maternal effects within these traits indicated mostly favourable relationship. Genetic antagonism was found between birth weight and early growth. Heritability (repeatability) for 90-day and total milk yield was 0.16-0.23 and 0.23-0.24 (0.28 and 0.39-0.40), respectively and 0.04-0.05 (0.10-0.11) for litter size. The genetic correlation between 90-day (total) milk yield and litter size was 0.45 (0.22). The correlation between the milk yield and the maternal genetic effects for the preweaning gain was very high (0.94). Selection schemes aiming to improve meat (litter size and growth) and milk production simultaneously are feasible. The increased milk production serves also for the acceleration of early growth in kids.

  9. Late Pleistocene climate change and the global expansion of anatomically modern humans

    Science.gov (United States)

    Eriksson, Anders; Betti, Lia; Friend, Andrew D.; Lycett, Stephen J.; Singarayer, Joy S.; von Cramon-Taubadel, Noreen; Valdes, Paul J.; Balloux, Francois; Manica, Andrea

    2012-01-01

    The extent to which past climate change has dictated the pattern and timing of the out-of-Africa expansion by anatomically modern humans is currently unclear [Stewart JR, Stringer CB (2012) Science 335:1317–1321]. In particular, the incompleteness of the fossil record makes it difficult to quantify the effect of climate. Here, we take a different approach to this problem; rather than relying on the appearance of fossils or archaeological evidence to determine arrival times in different parts of the world, we use patterns of genetic variation in modern human populations to determine the plausibility of past demographic parameters. We develop a spatially explicit model of the expansion of anatomically modern humans and use climate reconstructions over the past 120 ky based on the Hadley Centre global climate model HadCM3 to quantify the possible effects of climate on human demography. The combinations of demographic parameters compatible with the current genetic makeup of worldwide populations indicate a clear effect of climate on past population densities. Our estimates of this effect, based on population genetics, capture the observed relationship between current climate and population density in modern hunter–gatherers worldwide, providing supporting evidence for the realism of our approach. Furthermore, although we did not use any archaeological and anthropological data to inform the model, the arrival times in different continents predicted by our model are also broadly consistent with the fossil and archaeological records. Our framework provides the most accurate spatiotemporal reconstruction of human demographic history available at present and will allow for a greater integration of genetic and archaeological evidence. PMID:22988099

  10. Using 3D Modeling Techniques to Enhance Teaching of Difficult Anatomical Concepts.

    Science.gov (United States)

    Pujol, Sonia; Baldwin, Michael; Nassiri, Joshua; Kikinis, Ron; Shaffer, Kitt

    2016-04-01

    Anatomy is an essential component of medical education as it is critical for the accurate diagnosis in organs and human systems. The mental representation of the shape and organization of different anatomical structures is a crucial step in the learning process. The purpose of this pilot study is to demonstrate the feasibility and benefits of developing innovative teaching modules for anatomy education of first-year medical students based on three-dimensional (3D) reconstructions from actual patient data. A total of 196 models of anatomical structures from 16 anonymized computed tomography datasets were generated using the 3D Slicer open-source software platform. The models focused on three anatomical areas: the mediastinum, the upper abdomen, and the pelvis. Online optional quizzes were offered to first-year medical students to assess their comprehension in the areas of interest. Specific tasks were designed for students to complete using the 3D models. Scores of the quizzes confirmed a lack of understanding of 3D spatial relationships of anatomical structures despite standard instruction including dissection. Written task material and qualitative review by students suggested that interaction with 3D models led to a better understanding of the shape and spatial relationships among structures, and helped illustrate anatomical variations from one body to another. The study demonstrates the feasibility of one possible approach to the generation of 3D models of the anatomy from actual patient data. The educational materials developed have the potential to supplement the teaching of complex anatomical regions and help demonstrate the anatomical variation among patients. Copyright © 2016 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

  11. Seasonal variation of Brazilian red propolis: Antibacterial activity, synergistic effect and phytochemical screening.

    Science.gov (United States)

    Regueira, M S; Tintino, Saulo Relison; da Silva, Ana Raquel Pereira; Costa, Maria do Socorro; Boligon, Aline Augusti; Matias, Edinardo F F; de Queiroz Balbino, Valdir; Menezes, Irwin R A; Melo Coutinho, Henrique Douglas

    2017-09-01

    The aim of this study was to investigate the effect of the dry and rainy season on the antibacterial activity and chemical composition of the Brazilian red propolis. The samples were collected in rainy (RP-PER) and dry (RP-PED) seasons and analyzed by HPLC-DAD. The extracts were tested alone and in association with antibiotics against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus. The HPLC analysis identified luteolin and quercetin as the main compounds. Seasonal variation was observed according to concentrations of the compounds. The MIC values against E. coli ranged from 128 μg/mL to 512 μg/mL (EC 06 and EC ATCC). The red propolis showed MIC values of 512 μg/mL against both strains of P. aeruginosa used in our study (PA03 and PA24) and against strains of Gram-positive bacteria S. aureus the MICs ranged from 64 μg/mL to ≥1024 μg/mL (SA10). A synergistic effect was observed when we combined the RP-PED with gentamicin against all the strains tested. When we combined the RP-PED with Imipenem, we only observed synergistic effect against P. aeruginosa. According to our synergistic activity results, the utilization of red propolis collected in the drier periods can be used as an adjuvant against multiresistant bacterial infections. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Auxin effects on somaclonal variation and plant regeneration from mature embryo of barley (hordeum vulgare L.)

    International Nuclear Information System (INIS)

    Aydin, M.; Taspinar, M. S.; Arslan, E.; Sigmaz, B.; Agar, G.

    2015-01-01

    Crop improvement through genetic engineering depends on effective and reproducible plant regeneration systems. In barley (Hordeum vulgare L.), immature embryos are the most commonly used as explant source for In vitro regeneration and genetic transformation but, mature embryos are alternative to immature embryo due to the fact that they have advantages such as easy storage and ready availability throughout the year. The effects of different concentrations (2, 4, 6, 8, 10 and 12 mg/l) of three auxins (2,4-D, dicamba and picloram) were evaluated in mature embryo culture of barley. Calli, embryogenic calli and regenerated plants were observed in all of the studied auxins. The MS (Murashige and Skoog basal medium) containing 12 mg/l dicamba was found to be the most effective for embryogenic callus, responded embryogenic callus and regeneration efficiency. Plant tissue culture can bring about genetic changes that are known as somaclonal variation. Genetic and epigenetic changes were examined by RAPD (Randomly Amplified Polymorphic DNA) and CRED-RA (Coupled Restriction Enzyme Digestion-Random Amplification) techniques, respectively. Increased auxin concentration led to the decrease in the GTS (Genomic Template Stability) value. DNA hypermethylation occurred in higher concentrations of 2,4-D and picloram, while DNA hypomethylation was observed in dicamba. (author)

  13. 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.

  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. 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.

  16. 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

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

    DEFF Research Database (Denmark)

    Høgedahl, Laust

    2014-01-01

    The presence of an unemployment insurance system based on voluntary membership in unemployment insurance funds (known as the ‘Ghent system’) and a high union density has long been known and well documented and even referred to as a special ‘Ghent effect’. However the Ghent system, especially...... in the three classic Ghent countries Finland, Sweden and Denmark have come under significant pressure in recent years and many researchers are referring to an erosion of the Ghent system as a recruiting mechanism for trade unions. But prior research aimed at documenting the Ghent effect seems to disregard...... variations in how strongly trade unions benefit from the Ghent system as a recruiting mechanism. Hence, this article sets out to investigate whether all trade unions equally benefit from a Ghent effect across different sectors and occupations by studying the Danish case. Unique survey data made it possible...

  18. Effects of the Observed Meridional Flow Variations since 1996 on the Sun's Polar Fields

    Science.gov (United States)

    Hathaway, David H.; Upton, Lisa

    2013-01-01

    The cause of the low and extended minimum in solar activity between Sunspot Cycles 23 and 24 was the small size of Sunspot Cycle 24 itself - small cycles start late and leave behind low minima. Cycle 24 is small because the polar fields produced during Cycle 23 were substantially weaker than those produced during the previous cycles and those (weak) polar fields are the seeds for the activity of the following cycle. The polar fields are produced by the latitudinal transport of magnetic flux that emerged in low-latitude active regions. The polar fields thus depend upon the details of both the flux emergence and the flux transport. We have measured the flux transport flows (differential rotation, meridional flow, and supergranules) since 1996 and find systematic and substantial variation in the meridional flow alone. Here we present experiments using a Surface Flux Transport Model in which magnetic field data from SOHO/MDI and SDO/HMI are assimilated into the model only at latitudes between 45-degrees north and south of the equator (this assures that the details of the active region flux emergence are well represented). This flux is then transported in both longitude and latitude by the observed flows. In one experiment the meridional flow is given by the time averaged (and north-south symmetric) meridional flow profile. In the second experiment the time-varying and north-south asymmetric meridional flow is used. Differences between the observed polar fields and those produced in these two experiments allow us to ascertain the effects of these meridional flow variations on the Sun s polar fields.

  19. Effects of Tidally Driven Variation on the Response of Coralline Algae to Ocean Acidification

    Science.gov (United States)

    Ets-Hokin, J. M.; Fachon, E.; Donham, E. M.; Price, N.

    2016-02-01

    As atmospheric CO2 levels continue to rise, our oceans are becoming more acidic, making it difficult for calcareous organisms like coralline algae to calcify. Coralline algae are early colonizers after disturbances and foundational species that initiate succession by inducing larval settlement of many invertebrate species. However, coralline algae tend to be more susceptible to experimentally elevated pCO2 than other calcifiers, likely due to the higher magnesium content in their calcite skeleton, which can render them more soluble. Magnesium content varies between individuals and is context dependent, thus could be a mechanism of acclimation for algae recruiting to harsh environments. To test this hypothesis, we collected Corallina officinalis from tide pools that experience extreme daily variation and from a well-flushed site that experiences lower daily variation in seawater pH. Samples were placed for 22 days in 1L microcosms bubbled with air enriched with pCO2, with values ranging from preindustrial lows (280 uatm) to predicted highs over the next century (1120 uatm) over 6 treatment levels. C. officinalis collected in the isolated tide pools showed decreased growth ( 50%) both in net calcification (measured via buoyant weight method) and linear extension (visualized with fluorescent stain) in low and high pCO2 levels, with growth peaking at an optimal pCO2 value of approximatly 300 uatm similar to present-day conditions. In contrast C. officinalis collected from the flushed site had no response to pCO2 treatments but had significantly lower growth overall. Tide pool two showed higher inclusion of magnesium in its carbonate skeleton which could explain its more pronounced response to the pCO2 treatments. While living in harsh environments can acclimate coralline algae to high pCO2, overall growth rates are substantially lower and will likely be insufficient to alleviate effects of ocean acidification.

  20. Effect of culture methods on individual variation in the growth of sea cucumber Apostichopus japonicus within a cohort and family

    Science.gov (United States)

    Qiu, Tianlong; Zhang, Libin; Zhang, Tao; Bai, Yucen; Yang, Hongsheng

    2014-07-01

    There is substantial individual variation in the growth rates of sea cucumber Apostichopus japonicus individuals. This necessitates additional work to grade the seed stock and lengthens the production period. We evaluated the influence of three culture methods (free-mixed, isolated-mixed, isolated-alone) on individual variation in growth and assessed the relationship between feeding, energy conversion efficiency, and individual growth variation in individually cultured sea cucumbers. Of the different culture methods, animals grew best when reared in the isolated-mixed treatment (i.e., size classes were held separately), though there was no difference in individual variation in growth between rearing treatment groups. The individual variation in growth was primarily attributed to genetic factors. The difference in food conversion efficiency caused by genetic differences among individuals was thought to be the origin of the variance. The level of individual growth variation may be altered by interactions among individuals and environmental heterogeneity. Our results suggest that, in addition to traditional seed grading, design of a new kind of substrate that changes the spatial distribution of sea cucumbers would effectively enhance growth and reduce individual variation in growth of sea cucumbers in culture.

  1. Effects of major geometric variations between intracavitary applications on pear-shaped isodose dimension in cancer of the cervix

    International Nuclear Information System (INIS)

    Kim, R. Y.

    1996-01-01

    PURPOSE: The basic principal of intracavitary brachytherapy for cancer of the cervix is based on specific loading rules to achieve a pear-shaped isodose distribution centered around the cervix. Recently, ICRU Report 38 recommends a dose reference volume for reporting. Our previous studies have confirmed that there is considerable variations of geometry between applications. This study is to evaluate the effect of major geometric variations on pear-shaped isodose dimension in manual afterloading low-dose-rate system. MATERIAL AND METHODS: One hundred orthogonal films of 50 patients with cancer of the cervix (2 applications/patient) were reviewed for comparative measurements of geometric variations between applications. Major geometric variations were found for 13 patients in lengths of tandem, 7 patients in colpostats separation and 16 patients in vaginal packing. The direct measurement of these geometric variations were compared with the three-dimensional measurement of the pear-shaped isodose enclosed by the point A between the two applications. RESULTS: The geometric variations in the width of colpostats separation and length of tandem were directly related to the width and height of the pear-shaped isodose dimension. The geometric relationship between the colpostats and distal tandem had an important effect on the thickness of the pear-shape. In optimization of poor geometry for rectum or bladder wall, high dose volume centered around the cervix is reduced without changing the overall pear-shaped volume due to changing configuration of the pear-shaped isodose. In our selected patients with two applications, variations in vaginal packing had no direct effect on the width and thickness of the pear-shape due to other variables. CONCLUSION: Major geometric variations between applications greatly affect the dimension of the pear-shaped isodose distribution. Optimization of poor geometry is quite limited without compromising the high-dose volume centered around the

  2. 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.

  3. Determining customer satisfaction in anatomic pathology.

    Science.gov (United States)

    Zarbo, Richard J

    2006-05-01

    Measurement of physicians' and patients' satisfaction with laboratory services has become a standard practice in the United States, prompted by national accreditation requirements. Unlike other surveys of hospital-, outpatient care-, or physician-related activities, no ongoing, comprehensive customer satisfaction survey of anatomic pathology services is available for subscription that would allow continual benchmarking against peer laboratories. Pathologists, therefore, must often design their own local assessment tools to determine physician satisfaction in anatomic pathology. To describe satisfaction survey design that would elicit specific information from physician customers about key elements of anatomic pathology services. The author shares his experience in biannually assessing customer satisfaction in anatomic pathology with survey tools designed at the Henry Ford Hospital, Detroit, Mich. Benchmarks for physician satisfaction, opportunities for improvement, and characteristics that correlated with a high level of physician satisfaction were identified nationally from a standardized survey tool used by 94 laboratories in the 2001 College of American Pathologists Q-Probes quality improvement program. In general, physicians are most satisfied with professional diagnostic services and least satisfied with pathology services related to poor communication. A well-designed and conducted customer satisfaction survey is an opportunity for pathologists to periodically educate physician customers about services offered, manage unrealistic expectations, and understand the evolving needs of the physician customer. Armed with current information from physician customers, the pathologist is better able to strategically plan for resources that facilitate performance improvements in anatomic pathology laboratory services that align with evolving clinical needs in health care delivery.

  4. Effect of diurnal variation, CYP2B6 genotype and age on the pharmacokinetics of nevirapine in African children

    NARCIS (Netherlands)

    Bienczak, A.; Cook, A.; Wiesner, L.; Mulenga, V.; Kityo, C.; Kekitiinwa, A.; Walker, A.S.; Owen, A.; Gibb, D.M.; Burger, D.M.; McIlleron, H.; Denti, P.

    2017-01-01

    OBJECTIVES: To characterize the effects of CYP2B6 polymorphisms, diurnal variation and demographic factors on nevirapine pharmacokinetics in African children. METHODS: Non-linear mixed-effects modelling conducted in NONMEM 7.3 described nevirapine plasma concentration-time data from 414 children

  5. Effect of Temperature Variation on Modal Frequency of Reinforced Concrete Slab and Beam in Cold Regions

    Directory of Open Access Journals (Sweden)

    Hanbing Liu

    2016-01-01

    Full Text Available Changes of modal frequencies induced by temperature variation can be more obvious than those caused by structural damage, which will lead to the false damage identification results. Therefore, quantifying the temperature effect on modal frequencies is a critical step to eliminate its interference in damage detection. Due to the nonuniform and time-dependent characteristics of temperature distribution, it is insufficient to obtain the reliable relationships between temperatures and modal frequencies using temperatures in air or at surface. In this paper, correlations between measured temperatures (air temperature, surface temperature, mean temperature, etc. and modal frequencies for the slab and beam are comparatively analyzed. And the quantitative models are constructed considering nonuniform temperature distribution. Firstly, the reinforced concrete slab and beam were constructed and placed outside the laboratory to be monitored. Secondly, the correlation coefficients between modal frequencies and three kinds of temperatures are calculated, respectively. Thirdly, simple linear regression models between mean temperature and modal frequencies are established for the slab and beam. Finally, five temperature variables are selected to construct the multiple linear regression models. Prediction results reveal that the proposed multiple linear regression models possess favorable accuracy to quantify the temperature effect on modal frequencies considering nonuniform temperature distribution.

  6. PTHR1 polymorphisms influence BMD variation through effects on the growing skeleton

    DEFF Research Database (Denmark)

    Vilariño-Güell, Carles; Miles, Lisa J; Duncan, Emma L

    2007-01-01

    We investigated whether polymorphisms in PTHR1 are associated with bone mineral density (BMD), to determine whether the association of this gene with BMD was due to effects on attainment of peak bone mass or effects on subsequent bone loss. The PTHR1 gene, including its 14 exons, their exon-intro...... and C52813T were associated with height (P = 0.006) and total body less head BMD (P = 0.02), corrected for age and gender, confirming the family findings. These findings suggest a role for PTHR1 variation in determining peak BMD. Udgivelsesdato: 2007-Oct....... A cohort of 634 families, including 1,236 men (39%) and 1,926 women (61%) ascertained with probands with low BMD (Z... most informative SNPs (minor allele frequency >5%) and the tetranucleotide repeat. In our osteoporosis families, association was noted between lumbar spine BMD and alleles of a known functional tetranucleotide repeat (U4) in the PTHR1 promoter region (P = 0.042) and between two and three marker...

  7. Effects of salinity variations on CODAR ranges during the 2016 Bonnet Carré Spillway Opening

    Science.gov (United States)

    Howden, S. D.; Diercks, A. R.; Hode, L. E.; Cambazoglu, M. K.; Martin, K. M.

    2017-12-01

    On January 10, 2016 the Bonnet Carré Spillway was opened to relieve flooding on the Mississippi River, diverting river water into Lake Pontchartrain and then through the western Mississippi Sound. As part of the response to understand the effects of the spillway opening on the Mississippi Sound, a pair of 25 MHz CODAR SeaSondes were deployed on the coast of the western Mississippi Sound to monitor surface currents. This presented the additional opportunity to run a natural experiment on the effect of salinity on the range of CODAR signals. During the spillway event, salinities in the CODAR coverage area, as measured by monitoring stations operated by a partnership between the Mississippi Department of Marine Resources and the United States Geological Survey in the Sound ranged from over 30 to less than 2. Ranges from the CODAR stations were significantly correlated with these salinities. Additionally, the Naval Coastal Ocean Model output, run with real-time river input plus the Bonnet Carré Spillway freshwater input, was available for the analyzes for the spillway event time frame. The observations and modeling were used to investigate the role of salinity on SeaSonde range and how well those variations agree with theory.

  8. 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.

  9. Effects of injection pressure variation on mixing in a cold supersonic combustor with kerosene fuel

    Science.gov (United States)

    Liu, Wei-Lai; Zhu, Lin; Qi, Yin-Yin; Ge, Jia-Ru; Luo, Feng; Zou, Hao-Ran; Wei, Min; Jen, Tien-Chien

    2017-10-01

    Spray jet in cold kerosene-fueled supersonic flow has been characterized under different injection pressures to assess the effects of the pressure variation on the mixing between incident shock wave and transverse cavity injection. Based on the real scramjet combustor, a detailed computational fluid dynamics model is developed. The injection pressures are specified as 0.5, 1.0, 2.0, 3.0 and 4.0 MPa, respectively, with the other constant operation parameters (such as the injection diameter, angle and velocity). A three dimensional Couple Level Set & Volume of Fluids approach incorporating an improved Kelvin-Helmholtz & Rayleigh-Taylor model is used to investigate the interaction between kerosene and supersonic air. The numerical simulations primarily concentrate on penetration depth, span expansion area, angle of shock wave and sauter mean diameter distribution of the kerosene droplets with/without evaporation. Validation has been implemented by comparing the calculated against the measured in literature with good qualitative agreement. Results show that the penetration depth, span-wise angle and expansion area of the transverse cavity jet are all increased with the injection pressure. However, when the injection pressure is further increased, the value in either penetration depth or expansion area increases appreciably. This study demonstrates the feasibility and effectiveness of the combination of Couple Level Set & Volume of Fluids approach and an improved Kelvin-Helmholtz & Rayleigh-Taylor model, in turn providing insights into scramjet design improvement.

  10. Genetic variation underlying psychosis-inducing effects of cannabis: critical review and future directions.

    Science.gov (United States)

    Decoster, Jeroen; van Os, Jim; Myin-Germeys, Inez; De Hert, Marc; van Winkel, Ruud

    2012-01-01

    Cannabis use is associated with an increased risk for psychotic disorder, yet most cannabis users do not develop psychosis, suggesting that other factors are also involved. This paper reviews the available evidence suggesting that differential sensitivity to the psychosis-inducing effects of cannabis may be related to underlying genetic liability. There is robust evidence that persons at psychometric risk for psychosis are most vulnerable to display psychotic symptoms subsequent to the use of cannabis. Multiple studies have also found that persons at familial risk for psychosis have an increased sensitivity to the effects of cannabis. Together, these findings support the concept of a biological interaction between cannabis use and one's underlying genetic vulnerability. At the molecular-genetic level, however, few (if any) interactions have been consistently replicated, although a reported interaction with variation in AKT1 is promising and deserves further follow-up. The apparent lack of consistent replication can be ascribed to problems of initial gene selection, statistical power, a bias towards positive results and insufficient attempts at true replication, leading to the conclusion that increased sample sizes, greater density of genetic markers and a stronger focus on true replication are necessary. The major challenge for molecular-genetic gene-environment interaction research will be to combine the agnostic detection of disorder-associated genetic variants from genome-wide studies with the hypothesis-based approach from epidemiological and neurobiological studies. Possible strategies for future cannabis interaction studies are discussed.

  11. Intensity-modulated radiotherapy as the boost or salvage treatment of nasopharyngeal carcinoma: The appropriate parameters in the inverse planning and the effect of patient's anatomic factors on the planning results

    International Nuclear Information System (INIS)

    Hsiung, C.-Y.; Hunt, Margie A.; Yorke, Ellen D.; Chui, C.-S.; Hu, Jason; Xiong, J.-P.; Ling, Clifton C.; Lo, S.-K.; Wang, C.-J.; Huang, E.-Y.; Amols, Howard I.

    2005-01-01

    The current study demonstrates that the large increase in normal tissue penalty often degrades target dose uniformity without a concomitant large improvement in normal tissue dose, especially in anatomically unfavorable patients. The excessively large normal tissue penalties do not improve treatment plans for patients having unfavorable geometry

  12. Anatomic breast coordinate system for mammogram analysis

    DEFF Research Database (Denmark)

    Karemore, Gopal; 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...... interface was identified as a curve passing through A and intersecting the pectoral muscle line. The nipple was defined as the origin of the coordinate system. A family of second order curves were defined through the nipple and intersecting the pectoral line (AD). Every pixel location in mammogram...

  13. 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. Copyright © 2016 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

  14. 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 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.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.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.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. Our results call for a case-by-case analysis in a

  15. Anatomical basis for the fastigial pressor response.

    Science.gov (United States)

    Giuditta, Marianna; Ruggiero, David A; Del Bo, Alberto

    2003-01-01

    Electrical stimulation of rostromedial portion of cerebellar fastigial nucleus elicits integrated cardiovascular effects, which are neurally and humorally mediated. In this study, we sought to demonstrate the anatomical substrates of the fastigial pressor response (FPR) in the rat. The response was electrophysiologically localized in anesthetized, paralyzed-ventilated rats. Anterograde transport techniques were used to study the efferent projections of the fastigial pressor area; the distribution of efferent projection cells were then mapped by injecting retrograde tracers into anterogradely labeled sites. Electrolytic lesions were then placed bilaterally in selected brainstem areas in the attempt to block the pressor response. Sites of cerebellar stimulation and of brainstem lesions were subsequently histologically identified. The following lesions abolished the FPR: in nine animals lesions involved portions of the nucleus gigantocellularis dorsalis (NGCd), paramedian reticular formation (PMN) and the nucleus tractus solitarii (NTS) (in two animals fairly selectively the caudal NTS); in two other animals lesions destroyed the rostral ventrolateral medulla (C1 area) and in one animal the area encompassing the dorsal convexity of the superior cerebellar peduncle bordering the locus coeruleus-lateral parabrachial complex; partially effective were unilateral lesions of NGCd and NTS (three), bilateral lesions confined to NGCd and PMN (two), to vestibular complex and uncinate fasciculus (UF) (three), to UF and locus coeruleus (three) and to nucleus reticularis ventralis (two). Ineffective lesions involved A1 area, the nucleus gigantocellularis ventralis (NGCv), the spinal trigeminal nucleus and nucleus reticularis parvocellularis, the A5 area of the ventrolateral pons, the central gray and lateral mesencephalic tegmentum. It seems therefore that the pressor response elicited by stimulation of the cerebellar fastigial nucleus utilizes central specific pathways, as

  16. 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...

  17. Lacrimal Gland Pathologies from an Anatomical Perspective

    Directory of Open Access Journals (Sweden)

    Mahmut Sinan Abit

    2015-06-01

    Full Text Available Most of the patients in our daily practice have one or more ocular surface disorders including conjucntivitis, keratitis, dry eye disease, meibomian gland dysfunction, contact lens related symptoms, refractive errors,computer vision syndrome. Lacrimal gland has an important role in all above mentioned pathologies due to its major secretory product. An anatomical and physiological knowledge about lacrimal gland is a must in understanding basic and common ophthalmological cases. İn this paper it is aimed to explain the lacrimal gland diseases from an anatomical perspective.

  18. Anatomic correlates of deep brain stimulation electrode impedance.

    Science.gov (United States)

    Satzer, David; Maurer, Eric W; Lanctin, David; Guan, Weihua; Abosch, Aviva

    2015-04-01

    The location of the optimal target for deep brain stimulation (DBS) of the subthalamic nucleus (STN) remains controversial. Electrode impedance affects tissue activation by DBS and has been found to vary by contact number, but no studies have examined association between impedance and anatomic location. To evaluate the relationship between electrode impedance and anatomic contact location, and to assess the clinical significance of impedance. We gathered retrospective impedance data from 101 electrodes in 73 patients with Parkinson's disease. We determined contact location using microelectrode recording (MER) and high-field 7T MRI, and assessed the relationship between impedance and contact location. For contact location as assessed via MER, impedance was significantly higher for contacts in STN, at baseline (111 Ω vs STN border, p=0.03; 169 Ω vs white matter, pimpedance was lowest in contacts situated at STN border (p=0.03). Impedance did not vary by contact location as assessed via imaging. Location determination was 75% consistent between MER and imaging. Impedance was inversely related to absolute symptom reduction during stimulation (-2.5 motor portion of the Unified Parkinson's Disease Rating Scale (mUPDRS) points per 1000 Ω, p=0.01). In the vicinity of DBS electrodes chronically implanted in STN, impedance is lower at the rostral STN border and in white matter, than in STN. This finding suggests that current reaches white matter fibres more readily than neuronal cell bodies in STN, which may help explain anatomic variation in stimulation efficacy. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  19. Five mental foramina in the same mandible: CBCT findings of an unusual anatomical variant.

    Science.gov (United States)

    Borghesi, Andrea; Pezzotti, Stefania; Nocivelli, Giorgio; Maroldi, Roberto

    2018-01-09

    The mental foramen is an important anatomic landmark located on the buccal aspect of the mandible, typically near the apex of the second premolar. Mental foramina exhibit many anatomical variations, including differences in size, shape, position, and number. The most frequent type of variation in number is the presence of double mental foramen, which has a reported incidence ranging from 1.4 to 12.5%. The incidence of triple mental foramen ranges from 0.7 to 1.2%. The frequency of accessory mental foramina varies among ethnic groups, with a low incidence in white Caucasian populations. At present, cone beam computed tomography (CBCT) is the diagnostic tool of choice for examining the maxillofacial region, and the high spatial resolution of CBCT allows accurate three-dimensional analysis of mental foramen variations. The present report describes an unusual case of five mental foramina in a 24-year-old white European male diagnosed by CBCT.

  20. 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. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. The Extended Community-Level Effects of Genetic Variation in Foliar Wax Chemistry in the Forest Tree Eucalyptus globulus.

    Science.gov (United States)

    Gosney, Benjamin; O'Reilly-Wapstra, Julianne; Forster, Lynne; Whiteley, Carmen; Potts, Brad

    2017-05-01

    Genetic variation in foundation trees can influence dependent communities, but little is known about the mechanisms driving these extended genetic effects. We studied the potential chemical drivers of genetic variation in the dependent foliar community of the focal tree Eucalyptus globulus. We focus on the role of cuticular waxes and compare the effects to that of the terpenes, a well-studied group of secondary compounds known to be bioactive in eucalypts. The canopy community was quantified based on the abundance of thirty-nine distinctive arthropod and fungal symptoms on foliar samples collected from canopies of 246 progeny from 13 E. globulus sub-races grown in a common garden trial. Cuticular waxes and foliar terpenes were quantified using gas chromatography - mass spectrometry (GC-MC). A total of 4 of the 13 quantified waxes and 7 of the 16 quantified terpenes were significantly associated with the dependent foliar community. Variation in waxes explained 22.9% of the community variation among sub-races, which was equivalent to that explained by terpenes. In combination, waxes and terpenes explained 35% of the genetic variation among sub-races. Only a small proportion of wax and terpene compounds showing statistically significant differences among sub-races were implicated in community level effects. The few significant waxes have previously shown evidence of divergent selection in E. globulus, which signals that adaptive variation in phenotypic traits may have extended effects. While highlighting the role of the understudied cuticular waxes, this study demonstrates the complexity of factors likely to lead to community genetic effects in foundation trees.

  2. The Effect of Selected Conditions in a Thermoforming Process on Wall Thickness Variations

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    Emil Sasimowski

    2017-12-01

    Full Text Available The paper reports the results of a study on the effect of selected conditions in a thermoforming process for thin polystyrene sheet by vacuum assisted drape forming on the wall thickness non-uniformity of finished parts. The investigation was performed using Statistica’s DOE module for three variables: temperatures in the external and internal zones of the heater as well as heating time of the plastic sheet. The results demonstrate that the wall thickness in the finished parts at the measuring points is primarily affected by the heating time and the temperature in the internal zone of the heater, while the temperature in the external zone only affects some regions of the finished part. The results demonstrate that a short heating time and hence a lower temperature of the plastic sheet lead to a more uniform deformation of both the bottom and the side walls of the finished part, and as a consequence, to smaller variations in the wall thickness. The shortening of the heating time is however limited by the necessity of accurate reproduction of the shape of the finished part.

  3. 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.

  4. Phase variation of Opa proteins of Neisseria meningitidis and the effects of bacterial transformation.

    Science.gov (United States)

    Sadarangani, Manish; Hoe, Claire J; Makepeace, Katherine; van der Ley, Peter; Pollard, Andrew J

    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 opa genes 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 (r(2) = 0.77, p = 0.1212). Bacterial transformation resulted in a 180-fold increase in PV rate. The majority of opa genes 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.

  5. EFFECT OF POSTURAL VARIATION ON LUNG FUNCTION IN PATIENTS WITH MULTIPLE SCLEROSIS

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    Bruna Corrêa

    2013-07-01

    Full Text Available Introduction: Multiple Sclerosis (MS is an autoimmune disease that causes demyelination and inflammation, affecting young adults, and its progression leads to reduction in respiratory muscle strength. Objective: To evaluate respiratory muscle strength (RMS in the sitting and supine 90 ° to 0 ° in patients with MS and compare the values obtained with those of healthy individuals of the same gender and age. Methods: This is a cross-sectional study, quantitative, type Case Study, which evaluated the FMR by manometer in two different positions, sitting and supine 90 ° to 0 °. We evaluated 02 individuals with MS aged 22 (Case 1 and 57 (Case 2 years, females were also evaluated 02 healthy subjects. Data were analyzed and expressed as a percentage change. Results: It was observed that the FMR in MS patients is reduced by 50.44% compared to healthy individuals, in the sitting to 90 ° as in the supine position at 0 °. The effect of postural variation was noted that Case 1 showed better results for MIP and MEP in the sitting position and the second case, improvement was found in that same position, only the MEP. Conclusion: FMR in MS patients was lower compared with healthy individuals of the same gender and age, regardless of body position. The values of maximal respiratory pressures were higher when measured in a sitting position, but without great percentage difference compared with the supine position at 0 °.

  6. 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.

  7. An anatomically comprehensive atlas of the adult human brain transcriptome

    Science.gov (United States)

    Guillozet-Bongaarts, Angela L.; Shen, Elaine H.; Ng, Lydia; Miller, Jeremy A.; van de Lagemaat, Louie N.; Smith, Kimberly A.; Ebbert, Amanda; Riley, Zackery L.; Abajian, Chris; Beckmann, Christian F.; Bernard, Amy; Bertagnolli, Darren; Boe, Andrew F.; Cartagena, Preston M.; Chakravarty, M. Mallar; Chapin, Mike; Chong, Jimmy; Dalley, Rachel A.; David Daly, Barry; Dang, Chinh; Datta, Suvro; Dee, Nick; Dolbeare, Tim A.; Faber, Vance; Feng, David; Fowler, David R.; Goldy, Jeff; Gregor, Benjamin W.; Haradon, Zeb; Haynor, David R.; Hohmann, John G.; Horvath, Steve; Howard, Robert E.; Jeromin, Andreas; Jochim, Jayson M.; Kinnunen, Marty; Lau, Christopher; Lazarz, Evan T.; Lee, Changkyu; Lemon, Tracy A.; Li, Ling; Li, Yang; Morris, John A.; Overly, Caroline C.; Parker, Patrick D.; Parry, Sheana E.; Reding, Melissa; Royall, Joshua J.; Schulkin, Jay; Sequeira, Pedro Adolfo; Slaughterbeck, Clifford R.; Smith, Simon C.; Sodt, Andy J.; Sunkin, Susan M.; Swanson, Beryl E.; Vawter, Marquis P.; Williams, Derric; Wohnoutka, Paul; Zielke, H. Ronald; Geschwind, Daniel H.; Hof, Patrick R.; Smith, Stephen M.; Koch, Christof; Grant, Seth G. N.; Jones, Allan R.

    2014-01-01

    Neuroanatomically precise, genome-wide maps of transcript distributions are critical resources to complement genomic sequence data and to correlate functional and genetic brain architecture. Here we describe the generation and analysis of a transcriptional atlas of the adult human brain, comprising extensive histological analysis and comprehensive microarray profiling of ~900 neuroanatomically precise subdivisions in two individuals. Transcriptional regulation varies enormously by anatomical location, with different regions and their constituent cell types displaying robust molecular signatures that are highly conserved between individuals. Analysis of differential gene expression and gene co-expression relationships demonstrates that brain-wide variation strongly reflects the distributions of major cell classes such as neurons, oligodendrocytes, astrocytes and microglia. Local neighbourhood relationships between fine anatomical subdivisions are associated with discrete neuronal subtypes and genes involved with synaptic transmission. The neocortex displays a relatively homogeneous transcriptional pattern, but with distinct features associated selectively with primary sensorimotor cortices and with enriched frontal lobe expression. Notably, the spatial topography of the neocortex is strongly reflected in its molecular topography— the closer two cortical regions, the more similar their transcriptomes. This freely accessible online data resource forms a high-resolution transcriptional baseline for neurogenetic studies of normal and abnormal human brain function. PMID:22996553

  8. Anatomical Considerations on Surgical Anatomy of the Carotid Bifurcation

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    Adamantios Michalinos

    2016-01-01

    Full Text Available Surgical anatomy of carotid bifurcation is of unique importance for numerous medical specialties. Despite extensive research, many aspects such as precise height of carotid bifurcation, micrometric values of carotid arteries and their branches as their diameter, length, and degree of tortuosity, and variations of proximal external carotid artery branches are undetermined. Furthermore carotid bifurcation is involved in many pathologic processes, atheromatous disease being the commonest. Carotid atheromatous disease is a major predisposing factor for disabling and possibly fatal strokes with geometry of carotid bifurcation playing an important role in its natural history. Consequently detailed knowledge of various anatomic parameters is of paramount importance not only for understanding of the disease but also for design of surgical treatment, especially selection between carotid endarterectomy and carotid stenting. Carotid bifurcation paragangliomas constitute unique tumors with diagnostic accuracy, treatment design, and success of operative intervention dependent on precise knowledge of anatomy. Considering those, it becomes clear that selection and application of proper surgical therapy should consider anatomical details. Further research might ameliorate available treatment options or even lead to innovative ones.

  9. CHRONIC LOWER BACKACHE: IS THIS THE ANATOMICAL ANSWER

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    Shivanand

    2016-03-01

    Full Text Available INTRODUCTION Sacrum is a flat bone which is triangular in shape and is actually formed by the fusion of five sacral vertebras. It connects the two hip bones posteriorly and superiorly it articulates with the fifth lumbar vertebra and distally with the coccyx. Majority of the times the coccyx will be fused with the sacrum. The spines of the vertebra fuse posteriorly but there is a hiatus at the lower end of medial crest because of the failure of fusion of the lamina of the fifth sacral vertebra. Back pain is the most common complaint in the modern life. In some incidences sacralisation of lumbar vertebra seems to be the most common cause for backache. The main aim of the study is to find:  To find out the anatomical variations in the level at which the hiatus opens.  To find out if sacralisation occurs and if present, to make an attempt to find the frequency of the condition.  To find out if sacralisation is associated with other anatomical defects. The study was done in Mysore Medical College from January 2012 to May 2012. Five hundred sacral bones were studied. The sacralisation was observed in Six vertebras. i.e. they were observed in 1.2% of the cases. In one bone there non-fusion of first sacral lamina was observed. The knowledge of the hiatal opening is very important to the people who are practicing Medicine, Orthopedics and Gynecology

  10. Seasonal variation in standardized litter decomposition and effects of elevation and land use at Mount Kilimanjaro

    Science.gov (United States)

    Becker, Joscha; Kuzyakov, Yakov

    2017-04-01

    Decomposition is one of most important ecological steps in organic matter and nutrient cycles, but studies and reliable data from tropical regions in Africa are still scarce. At the global scale, litter decomposition and recycling is controlled by climatic factors and land-use intensity. These factors can be linked to specific ecosystem characteristics along the unique elevation gradient of Mt. Kilimanjaro. Our objectives were to assess the effects of climatic conditions (i.e. elevation) and land-use intensity on C turnover and stabilization and investigated the seasonal variations. Tea-bag Index (see www.teatime4science.org) was used to measure decomposition of a standardized litter substrate by microorganisms and mesofauna warm-dry (December-March), long-rainy (March-July) and cold-dry season (July-September) respectively. Decomposition rates increased from k=0.007 in savanna, up to a maximum of k=0.022 in cloud forest (i.e. mid elevation). The increase was followed by a decrease of 50% in (sub-) alpine ecosystems. Stabilization factors decreased from savanna (S=0.33) to coffee plantations or cloud forest (S=0.11) respectively and strongly increased again to a maximum of S=0.41 in the alpine helichrysum ecosystem. During all seasons, we found the highest decomposition rates at mid elevation. However, during both warm seasons the peak is shifted upslope. Savanna experienced the strongest seasonal variation, with 23 times higher S-values in dry- compared to rainy season. Mean annual k-values increased for about 30% with increasing land-use intensity. C stabilization in Mt. Kilimanjaro ecosystems is strongly dependent on seasonal moisture limitation (lower slope) and perennial temperature limitation (alpine zone). Ecosystems at mid elevation (around 1920 & 2120m) represent the interception zone of optimal moisture and temperature conditions. High input and fast turnover drive the C sequestration in these ecosystems, while restrains on decomposition control the C

  11. Qualitative and quantitative estimations of the effect of geomagnetic field variations on human brain functional state

    International Nuclear Information System (INIS)

    Belisheva, N.K.; Popov, A.N.; Petukhova, N.V.; Pavlova, L.P.; Osipov, K.S.; Tkachenko, S.Eh.; Baranova, T.I.

    1995-01-01

    The comparison of functional dynamics of human brain with reference to qualitative and quantitative characteristics of local geomagnetic field (GMF) variations was conducted. Steady and unsteady states of human brain can be determined: by geomagnetic disturbances before the observation period; by structure and doses of GMF variations; by different combinations of qualitative and quantitative characteristics of GMF variations. Decrease of optimal GMF activity level and the appearance of aperiodic disturbances of GMF can be a reason of unsteady brain's state. 18 refs.; 3 figs

  12. 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

    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...... freshwater fish species in North America. We then use length at age data from yellow perch (Perca flavescens) to identify the mechanisms behind the remaining variation in the length at age – temperature relationship for walleye. A positive perch – walleye relationship indicates that the mechanism behind...

  13. Effects of Viscosity Variation and Surface Roughness on the Couple stress Squeeze Film Characteristics of Short Journal Bearings

    Directory of Open Access Journals (Sweden)

    G.H. Ayyappa

    2015-03-01

    Full Text Available The theoretical analysis of the combined effects of surface roughness and viscosity variation on the couple stress squeeze film characteristics of short journal bearings is presented. The modified stochastic Reynold’s equation accounting for the viscosity variation of couple stresses fluid and randomized surface roughness structure on bearing surface is mathematically derived using the Christensen stochastic theory. It is observed that, the transverse roughness pattern improves the squeeze film characteristics whereas the bearing performance is affected due to the presence of one dimensional longitudinal surface roughness. Further, it is observed that, the effect of viscosity variation is to reduce the load carrying capacity and squeeze film time as compared to the case of constant viscosity.

  14. An anatomically realistic temperature phantom for radiofrequency heating measurements

    Science.gov (United States)

    Graedel, Nadine N.; Polimeni, Jonathan R.; Guerin, Bastien; Gagoski, Borjan; Wald, Lawrence L.

    2014-01-01

    Purpose An anthropomorphic phantom with realistic electrical properties allows for a more accurate reproduction of tissue current patterns during excitation. A temperature map can then probe the worst-case heating expected in the un-perfused case. We describe an anatomically realistic human head phantom that allows rapid 3D temperature mapping at 7 T. Methods The phantom was based on hand-labeled anatomical imaging data and consists of four compartments matching the corresponding human tissues in geometry and electrical properties. The increases in temperature resulting from radiofrequency excitation were measured with MR thermometry using a temperature sensitive contrast agent (TmDOTMA−) validated by direct fiber optic temperature measurements. Results Acquisition of 3D temperature maps of the full phantom with a temperature accuracy better than 0.1°C was achieved with an isotropic resolution of 5 mm and acquisition times of 2–4 minutes. Conclusion Our results demonstrate the feasibility of constructing anatomically realistic phantoms with complex geometries incorporating the ability to measure accurate temperature maps in the phantom. The anthropomorphic temperature phantom is expected to provide a useful tool for the evaluation of the heating effects of both conventional and parallel transmit pulses and help validate electromagnetic and temperature simulations. PMID:24549755

  15. Effects of small variations of speed of sound in optoacoustic tomographic imaging

    Energy Technology Data Exchange (ETDEWEB)

    Deán-Ben, X. Luís; Ntziachristos, Vasilis; Razansky, Daniel, E-mail: dr@tum.de [Institute for Biological and Medical Imaging, Technical University of Munich and Helmholtz Center Munich, Ingolstädter Landstraße 1, 85764 Neuherberg (Germany)

    2014-07-15

    Purpose: Speed of sound difference in the imaged object and surrounding coupling medium may reduce the resolution and overall quality of optoacoustic tomographic reconstructions obtained by assuming a uniform acoustic medium. In this work, the authors investigate the effects of acoustic heterogeneities and discuss potential benefits of accounting for those during the reconstruction procedure. Methods: The time shift of optoacoustic signals in an acoustically heterogeneous medium is studied theoretically by comparing different continuous and discrete wave propagation models. A modification of filtered back-projection reconstruction is subsequently implemented by considering a straight acoustic rays model for ultrasound propagation. The results obtained with this reconstruction procedure are compared numerically and experimentally to those obtained assuming a heuristically fitted uniform speed of sound in both full-view and limited-view optoacoustic tomography scenarios. Results: The theoretical analysis showcases that the errors in the time-of-flight of the signals predicted by considering the straight acoustic rays model tend to be generally small. When using this model for reconstructing simulated data, the resulting images accurately represent the theoretical ones. On the other hand, significant deviations in the location of the absorbing structures are found when using a uniform speed of sound assumption. The experimental results obtained with tissue-mimicking phantoms and a mouse postmortem are found to be consistent with the numerical simulations. Conclusions: Accurate analysis of effects of small speed of sound variations demonstrates that accounting for differences in the speed of sound allows improving optoacoustic reconstruction results in realistic imaging scenarios involving acoustic heterogeneities in tissues and surrounding media.

  16. Effect of structural variation on aldehyde oxidase-catalyzed oxidation of zoniporide.

    Science.gov (United States)

    Dalvie, Deepak; Sun, Hao; Xiang, Cathie; Hu, Qiyue; Jiang, Ying; Kang, Ping

    2012-08-01

    Current studies explored the effect of structural changes on the aldehyde oxidase (AO)-mediated metabolism of zoniporide (1). Zoniporide analogs with modifications of the acylguanidine moiety, the cyclopropyl group on the pyrazole ring, and the quinoline ring were studied for their AO-catalyzed metabolism using the human S9 fraction. Analysis of the half-lives suggested that subtle changes in the structure of 1 influenced its metabolism and that the guanidine and the quinoline moieties were prerequisites for AO-catalyzed oxidation to 2-oxozoniporide (M1). In contrast, replacement of the cyclopropyl group with other alkyl groups was tolerated. The effect of structural variation on AO properties was rationalized by docking 1 and its analogs into the human AO homology model. These studies indicated the importance of electrostatic, π-π stacking and hydrophobic interactions of the three motifs with residues in the active site. Differences in substrate properties were also rationalized by comparing their half-lives with cLogD, electrophilicity parameters [electrostatic potential (ESP) charges and energy of lowest unoccupied molecular orbitals (E(LUMO))], and the energies of formation of tetrahedral intermediates (J Med Chem 50:4642-4647, 2007). Whereas the success of energetics in predicting the AO substrate properties of analogs was 87%, the predictive ability of other descriptors was none (cLogD) to 60% (ESP charges and E(LUMO)). Overall, the structure-metabolism relationship could be rationalized using a combination of both the energy calculations and docking studies. This combination method can be incorporated into a strategy for mitigating AO liabilities observed in the lead candidate or studying structure-metabolism relationships of other AO substrates.

  17. Spatio-Temporal Variation and Monsoon Effect on the Temperature Lapse Rate of a Subtropical Island

    Directory of Open Access Journals (Sweden)

    Ching-An Chiu

    2014-01-01

    Full Text Available Temperature lapse rate (TLR has been widely used in the prediction of mountain climate and vegetation and in many ecological models. The aims of this paper are to explore the spatio-temporal variations and monsoon effects on the TLR in the subtropical island of Taiwan with its steep Central Mountain Region (CMR. A TLR analysis using the 32-year monthly mean air temperatures and elevations from 219 weather stations (sea level to 3852 m a.s.l. was performed based on different geographical regions and monsoon exposures. The results revealed that the average TLR for all of Taiwan is -5.17°C km-1, with a general tendency to be steeper in summer and shallower in winter. The results are also shallower than the typical or global average TLR of -6.5°C km-1. During the prevailing northeast monsoon season (winter, the TLR exhibits a contrast between the windward side (steeper, -5.97°C km-1 and the leeward side (shallower, -4.51°C km-1. From the diagnosis on spatial characteristics of monthly cloud amount and vertical atmospheric profiles, this contrasting phenomenon may be explained by the warming effect of onshore stratus clouds (500 - 2500 m depth on cold and dry Siberian monsoon air on the windward side of the CMR. On the southwestern leeward side of the CMR, the low-level (1500 m, the weak ventilation atmosphere and temperature inversion make the TLR shallower than on the windward side.

  18. Copper-induced metabolic variation of oysters overwhelmed by salinity effects.

    Science.gov (United States)

    Cao, Chen; Wang, Wen-Xiong

    2017-05-01

    In estuarine environments, Cu (copper) contamination is simultaneously coupled with salinity variation. In this study, 1 H NMR was applied to investigate the metabolic disturbance of estuarine oysters Crassostrea hongkongensis under both Cu and salinity stresses. Oysters were exposed to dissolved Cu (50 μg L -1 ) at different salinities (10, 15 and 25 psu) for six weeks, and the Cu accumulation in the oyster tissues was higher at lowered salinity. Based on the NMR-metabolomics results, disturbances induced by Cu and salinity was mainly related to osmotic regulation, energy metabolism and glycerophospholipid metabolism, as indicated by the alteration of important metabolic biomarkers such as alanine, citrate, glucose, glycogen, betaine, taurine, hypotaurine and homarine in the gills. At lower salinity, oysters accumulated higher energy related compounds (e.g., glucose and glycogen) and amino acids (e.g., aspartate, dimethylglycine and lysine), with the enhancement of ATP/ADP production and accumulation of oxidizable amino acids catabolized from protein breakdown. With Cu exposure, the synthesis from glycine to dimethylglycine was observed to cope with severe osmotic stress, together with the elevation of lysine and homarine. The effects induced by Cu were much similar for each salinity treatment, but the combination of Cu and salinity turned out to be consistent with the singular salinity effects. Therefore, salinity played a dominant role in affecting the metabolites of oysters when combined with Cu exposure. This study indicated that salinity should be taken into consideration in order to predict the Cu toxicity in estuarine organisms. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Effects of small variations of speed of sound in optoacoustic tomographic imaging

    International Nuclear Information System (INIS)

    Deán-Ben, X. Luís; Ntziachristos, Vasilis; Razansky, Daniel

    2014-01-01

    Purpose: Speed of sound difference in the imaged object and surrounding coupling medium may reduce the resolution and overall quality of optoacoustic tomographic reconstructions obtained by assuming a uniform acoustic medium. In this work, the authors investigate the effects of acoustic heterogeneities and discuss potential benefits of accounting for those during the reconstruction procedure. Methods: The time shift of optoacoustic signals in an acoustically heterogeneous medium is studied theoretically by comparing different continuous and discrete wave propagation models. A modification of filtered back-projection reconstruction is subsequently implemented by considering a straight acoustic rays model for ultrasound propagation. The results obtained with this reconstruction procedure are compared numerically and experimentally to those obtained assuming a heuristically fitted uniform speed of sound in both full-view and limited-view optoacoustic tomography scenarios. Results: The theoretical analysis showcases that the errors in the time-of-flight of the signals predicted by considering the straight acoustic rays model tend to be generally small. When using this model for reconstructing simulated data, the resulting images accurately represent the theoretical ones. On the other hand, significant deviations in the location of the absorbing structures are found when using a uniform speed of sound assumption. The experimental results obtained with tissue-mimicking phantoms and a mouse postmortem are found to be consistent with the numerical simulations. Conclusions: Accurate analysis of effects of small speed of sound variations demonstrates that accounting for differences in the speed of sound allows improving optoacoustic reconstruction results in realistic imaging scenarios involving acoustic heterogeneities in tissues and surrounding media

  20. Effects of habitual variations in napping on psychomotor performance, memory and subjective states.

    Science.gov (United States)

    Taub, J M

    1979-01-01

    Effects of habitual variations in napping on psychomotor performance, short-term memory and subjective states were investigated. The subjects were 32 healthy male university students who napped twice or more weekly in themorning and at night. Sixteen were randomly assigned to a control group and 16 to a nap(treatment) group. The experiment comprised two conditions of electrographically (EEG) recorded sleep for the nap group and two EEG monitored conditions of wakefulness for the controls. These conditions were scheduled from 9:35 to 11:35 a.m. and 12 hr later between 9:35 p.m. and 11:35 p.m. Measurements were obtained from: (a) a continuous 10-min auditory reaction time task, (b) a free recall task of short-term memory, (c) an activation-mood adjective check list, and (d) the Stanford Sleepiness scale. Except for memory the dependent variables of waking function were assessed 20 min before and 20 min after all conditions. Following each sleep condition the nap group as opposed to the controls showed a statistically significant improvement in reaction time performance, higher short-term retention, less reported sleepiness and elevated subjective states reflected by fice factors on the adjective mood-activation check list. Among the correlations computed the largest significant coefficients were of stage 4 and REM with posttreatment Stanford Sleepiness ratings. After naps, increased postdormital sleepiness was correlated with stage 4 and decreased sleepiness with REM sleep. Although few strikingly divergent functional effects were associated with morning and nocturanal naps, these did covary with sleep psychophysiology. It is postulated that the phase, the EEG-sleep stages and possibly the duration of accustomed naps are less salient factors influencing performance when the time since awakening until behavioral assessment can be kept constant.

  1. Effect of Variation in Blending Variables on the Properties of CRMB

    Directory of Open Access Journals (Sweden)

    Naeem Aziz Memon

    2016-04-01

    Full Text Available The enhancement in the properties of the modified blends largely depends on the proper understanding of the interaction between CR (Crumb Rubber and bitumen, where the CR particles swell after absorbing lighter fraction from the bitumen phase. However, the properties of CRMB (Crumb Rubber Modified Bitumen blends at a wide range of temperatures are considered to be somewhat unclear due to the various interaction effects of CR and base bitumen. This largely depends on the interaction conditions such as blending time, temperature, speed and device, which may alter the properties of the blend to great extent. In this study, influence of the interaction condition was investigated by looking at the viscosity with a Brookfield viscometer. For this, CR and bitumen proportions along with other material characteristics were kept constant to understand the effect of interaction parameters of the properties of the CRMB blend. A total of 12 CRMB blends were produced with unvarying combinations of material constituents. However, selected variation in the blending parameters were; blending device, duration, speed and temperature. Observations from this laboratory study indicated: (1 blending performed with the high shear mixer resulted in higher viscosity values compared to the blends produced with the low shear mixer; (2 reduced blending time was required to achieve peak and ultimate stable viscosities, when blends were produced with the high shear mixer; (3 blending temperature of 180°C has resulted in the blends with consistent properties for longer blending durations compared to the blends produced at higher temperature. As a result, results with high shear mixer were always promising, which required comparatively lower interaction temperature, time and speed.

  2. 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. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Effect of Water Chemistry Variations on Corrosion of Zr-Alloys for BWR Applications

    International Nuclear Information System (INIS)

    Kim, Young-Jin; Yang- Lin, Pi; Lutz, Dan; Kucuk, Aylin; Cheng, Bo

    2012-09-01

    Two reference water chemistry conditions (60 ppb Zn and 60 μg/cm 2 Pt/Rh with either 500 ppb O 2 and 500 ppb H 2 O 2 , or 150 ppb H 2 ) were chosen for testing at 300 deg. C in refreshed autoclaves. For each reference water chemistry, the potential effects due to three chemical impurities of interest to BWRs (33 ppm Na, 10 ppm Li, and 10 ppm EHC fluid) were evaluated. Zircaloy-2 and GNF-Ziron (a Zr-based alloy with higher Fe additions than Zircaloy-2) cladding tubes were tested and the effects of tubing process variation and pre-filming were investigated. Tested channel materials included Zircaloy-2, Zircaloy-4, GNF-Ziron and NSF (a Zr-based alloy with Sn, Nb and Fe additions). The corrosion weight gain and hydrogen absorption were measured up to 12 months of exposure for a given water chemistry condition. Tests under 150 ppb H 2 based water chemistry, with or without chemical impurities, generally resulted in greater amounts of corrosion after 12 month exposure compared with 500 ppb O 2 and 500 ppb H 2 O 2 based water chemistries. Of the added chemical impurities, only 33 ppm Na addition produced slightly increased corrosion. Under various test conditions, the presence of a thin pre-film resulted in some initial corrosion benefits, but the benefits were no longer evident after 12 months exposure; however, slight hydrogen benefits remained. For GNF-Ziron cladding, hydrogen absorption was generally lower compared with similarly processed Zircaloy-2 under 150 ppb H 2 based water chemistry, when corrosion was generally higher. Of the channel material tested, NSF developed the lowest level of hydrogen absorption, particularly under 150 ppb H 2 based water chemistries. (authors)

  4. Quantifying the forcing effect of channel width variations on free bars: Morphodynamic modeling based on characteristic dissipative Galerkin scheme

    Science.gov (United States)

    Wu, Fu-Chun; Shao, Yun-Chuan; Chen, Yu-Chen

    2011-09-01

    The forcing effect of channel width variations on free bars is investigated in this study using a two-dimensional depth-averaged morphodynamic model. The novel feature of the model is the incorporation of a characteristic dissipative Galerkin (CDG) upwinding scheme in the bed evolution module. A correction for the secondary flows induced by streamline curvature is also included, allowing for simulations of bar growth and migration in channels with width variations beyond the small-amplitude regimes. The model is tested against a variety of experimental data ranging from purely forced and free bars to coexisting bed forms in the variable-width channel. The CDG scheme effectively dissipates local bed oscillations, thus sustains numerical stabilities. The results show that the global effect of width variations on bar height is invariably suppressive. Such effect increases with the dimensionless amplitude AC and wave number λC of width variations. For small AC, λC has little effects on bar height; for AC beyond small amplitudes, however, the suppressing effect depends on both AC and λC. The suppressing effect on bar length increases also with both AC and λC, but is much weaker than that on bar height. The global effect of width variations on bar celerity can be suppressive or enhancive, depending on the combination of AC and λC. For smaller λC, the effect on bar celerity is enhancive; for larger λC, bar celerity tends to increase at small AC but decreases for AC beyond small amplitudes. We present herein an unprecedented data set verifying the theoretical prediction on celerity enhancement. Full suppression of bar growth above the theoretically predicted threshold AC was not observed, regardless of the adopted amplitude of initial bed perturbation A. The global effects of width variations on free bars can be quantified using a forcing factor FC that integrates the effects of AC and λC. The suppressing effects on bar height and length are both proportional to FC

  5. Anatomical and palynological characteristics of Salvia willeana ...

    African Journals Online (AJOL)

    USER

    2010-04-05

    Apr 5, 2010 ... investigated in this study and the findings obtained were compared with other studies conducted on Salvia genus. Metcalfe and Chalk (1950) found the data on the anatomical characteristics of S. species. These researchers revealed that the species belonging to Labiatae family usually have rectangle or ...

  6. Descriptions of anatomical differences between skulls and ...

    African Journals Online (AJOL)

    The external anatomical differences between the skulls and mandibles of 10 mountain zebras Equus zebra and 10 plains zebras E. burchelli of both sexes were studied. The nomenclature used conforms to Nomina Anatomica Veterinaria (1983). Eleven structural differences are described for the first time and illustrated, viz., ...

  7. 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...

  8. Morphological and anatomical response of Acacia ehrenbergiana ...

    African Journals Online (AJOL)

    Both species responded morphologically as well as anatomically to water stress. Water stress caused significant (P=0.05) decrease in relative water content, leaf number and area and leaf water potential, chlorophyll content, and stem height and diameter. Seedlings of both species responded to water stress by the ...

  9. Anatomical characteristics of southern pine stemwood

    Science.gov (United States)

    Elaine T. Howard; Floyd G. Manwiller

    1968-01-01

    To obtain a definitive description of the wood and anatomy of all 10 species of southern pine, juvenile, intermediate, and mature wood was sampled at three heights in one tree of each species and examined under a light microscope. Photographs and three-dimensional drawings were made to illustrate the morphology. No significant anatomical differences were found...

  10. 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.

  11. 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.

  12. 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)

  13. Anatomical entity mention recognition at literature scale.

    Science.gov (United States)

    Pyysalo, Sampo; Ananiadou, Sophia

    2014-03-15

    Anatomical entities ranging from subcellular structures to organ systems are central to biomedical science, and mentions of these entities are essential to understanding the scientific literature. Despite extensive efforts to automatically analyze various aspects of biomedical text, there have been only few studies focusing on anatomical entities, and no dedicated methods for learning to automatically recognize anatomical entity mentions in free-form text have been introduced. We present AnatomyTagger, a machine learning-based system for anatomical entity mention recognition. The system incorporates a broad array of approaches proposed to benefit tagging, including the use of Unified Medical Language System (UMLS)- and Open Biomedical Ontologies (OBO)-based lexical resources, word representations induced from unlabeled text, statistical truecasing and non-local features. We train and evaluate the system on a newly introduced corpus that substantially extends on previously available resources, and apply the resulting tagger to automatically annotate the entire open access scientific domain literature. The resulting analyses have been applied to extend services provided by the Europe PubMed Central literature database. All tools and resources introduced in this work are available from http://nactem.ac.uk/anatomytagger. sophia.ananiadou@manchester.ac.uk Supplementary data are available at Bioinformatics online.

  14. Anatomically Plausible Surface Alignment and Reconstruction

    DEFF Research Database (Denmark)

    Paulsen, Rasmus R.; Larsen, Rasmus

    2010-01-01

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

  15. 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

  16. ANATOMIC STRUCTURE OF CAMPANULA ROTUNDIFOLIA L. GRASS

    Directory of Open Access Journals (Sweden)

    V. N. Bubenchikova

    2017-01-01

    Full Text Available The article present results of the study for a anatomic structure of Campanula rotundifolia grass from Campanulaceae family. Despite its dispersion and application in folk medicine, there are no data about its anatomic structure, therefore to estimate the indices of authenticity and quality of raw materials it is necessary to develop microdiagnostical features in the first place, which could help introducing of thisplant in a medical practice. The purpose of this work is to study anatomical structureof Campanula rotundifolia grass to determine its diagnostic features. Methods. Thestudy for anatomic structure was carried out in accordance with the requirements of State Pharmacopoeia, edition XIII. Micromed laboratory microscope with digital adjutage was used to create microphotoes, Photoshop CC was used for their processing. Result. We have established that stalk epidermis is prosenchymal, slightly winding with straight of splayed end cells. After study for the epidermis cells we established that upper epidermis cells had straight walls and are slightly winding. The cells of lower epidermishave more winding walls with prolong wrinkled cuticule. Presence of simple one-cell, thin wall, rough papillose hair on leaf and stalk epidermis. Cells of epidermis in fauces of corolla are prosenchymal, with winding walls, straight or winding walls in a cup. Papillary excrescences can be found along the cup edges. Stomatal apparatus is anomocytic. Conclusion. As the result of the study we have carried out the research for Campanula rotundifolia grass anatomic structure, and determined microdiagnostic features for determination of raw materials authenticity, which included presence of simple, one-cell, thin-walled, rough papillose hair on both epidermises of a leaf, along the veins, leaf edge, and stalk epidermis, as well as the presence of epidermis cells with papillary excrescences along the edges of leaves and cups. Intercellular canals are situatedalong the

  17. 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 NP/NS was higher than previously recorded in humans, and anatomical variation of carotid sinus location and equipment design can affect transmission results.

  18. Facial reconstruction – anatomical art or artistic anatomy?

    Science.gov (United States)

    Wilkinson, Caroline

    2010-01-01

    Facial reconstruction is employed in the context of forensic investigation and for creating three-dimensional portraits of people from the past, from ancient Egyptian mummies and bog bodies to digital animations of J. S. Bach. This paper considers a facial reconstruction method (commonly known as the Manchester method) associated with the depiction and identification of the deceased from skeletal remains. Issues of artistic licence and scientific rigour, in relation to soft tissue reconstruction, anatomical variation and skeletal assessment, are discussed. The need for artistic interpretation is greatest where only skeletal material is available, particularly for the morphology of the ears and mouth, and with the skin for an ageing adult. The greatest accuracy is possible when information is available from preserved soft tissue, from a portrait, or from a pathological condition or healed injury. PMID:20447245

  19. Effect of powder density variation on premixed Ti-6Al-4 V and Cu composites during laser metal deposition

    CSIR Research Space (South Africa)

    Erinosho, MF

    2016-05-01

    Full Text Available This paper reports the effect of powder density variation on the premixed Ti-6Al-4 V/Cu and Ti-6A-4 V/2Cu Composites. Two sets of experiment were conducted in this study. Five deposits each were made for the two premixed composites. Laser powers were...