bluuebunny/crossref_metadata_2025 huggingface dataset:
Functional diversity of phytochrome family in the control of light and gibberellin‐mediated germination in Arabidopsis
Authors: ARANA M. V. , SÁNCHEZ‐LAMAS M. , STRASSER B. , IBARRA S. E. , CERDÁN P. D. , BOTTO J. F. , SÁNCHEZ R. A.
Published: January 2014

In several species, seed germination is regulated by light in a way that restricts seedling emergence to the environmental conditions that are likely to be favourable for the success of the new individual, and therefore, this behaviour is recognized to have adaptive value. The phytochromes are one of the most relevant photoreceptors involved in light perception by plants. We explored the redundancy and diversity functions of the phytochrome family in the control of seed responsiveness to light and gibberellins (GA) by using a set of phytochrome mutants of Arabidopsis. Our data show that, in addition to the well‐known role of phyB in the promotion of germination in response to high red to far‐red ratios (R/FR), phyE and phyD stimulate germination at very low R/FR ratios, probably by promoting the action of phyA. Further, we show that phyC regulates negatively the seed responsiveness to light, unravelling unexpected functions for phyC in seed germination. Finally, we find that seed responsiveness to GA is mainly controlled by phyB, with phyC, phyD and phyE having relevant roles when acting in a phyB‐deficient background. Our results indicate that phytochromes have multiple and complex roles during germination depending on the active photoreceptor background.
The future of isoprene emission from leaves, canopies and landscapes
Authors: SHARKEY THOMAS D. , MONSON RUSSELL K.
Published: January 2014

Isoprene emission from plants plays a dominant role in atmospheric chemistry. Predicting how isoprene emission may change in the future will help predict changes in atmospheric oxidant, greenhouse gas and secondary organic aerosol concentrations in the future atmosphere. At the leaf‐scale, an increase in isoprene emission with increasing temperature is offset by a reduction in isoprene emission rate caused by increased CO2. At the canopy scale, increased leaf area index in elevated CO2 can offset the reduction in leaf‐scale isoprene emission caused by elevated CO2. At the landscape scale, a reduction in forest coverage may decrease, while forest fertilization and community composition dynamics are likely to cause an increase in the global isoprene emission rate. Here we review the potential for changes in the isoprene emission rate at all of these scales. When considered together, it is likely that these interacting effects will result in an increase in the emission of the most abundant plant volatile, isoprene, from the biosphere to the atmosphere in the future.
Inverse regulation of melanoma growth and migration by Orai1/STIM2‐dependent calcium entry
Authors: Stanisz Hedwig , Saul Stephanie , Müller Cornelia S. L. , Kappl Reinhard , Niemeyer Barbara A. , Vogt Thomas , Hoth Markus , Roesch Alexander , Bogeski Ivan
Published: January 2014

Spontaneous melanoma phenotype switching is controlled by unknown environmental factors and may determine melanoma outcome and responsiveness to anticancer therapy. We show that Orai1 and STIM2 are highly expressed and control store‐operated Ca2+ entry in human melanoma. Lower extracellular Ca2+ or silencing of Orai1/STIM2 caused a decrease in intracellular Ca2+, which correlated with enhanced proliferation and increased expression of microphthalmia‐associated transcription factor, a marker for proliferative melanoma phenotype. In contrast, the invasive and migratory potential of melanoma cells was reduced upon silencing of Orai1 and/or STIM2. Accordingly, markers for a non‐proliferative, tumor‐maintaining phenotype such as JARID1B and Brn2 decreased. Immunohistochemical staining of primary melanomas and lymph node metastases revealed a heterogeneous distribution of Orai1 and STIM2 with elevated expression in the invasive rim of the tumor. In summary, our results support a dynamic model in which Orai1 and STIM2 inversely control melanoma growth and invasion. Pharmacological tuning of Orai1 and particularly STIM2 might thus prevent metastatic spread and render melanomas more susceptible to conventional therapy.
Quantitative and in situ Detection of Oxidatively Generated DNA Damage 8,5′‐Cyclo‐2′‐Deoxyadenosine Using an Immunoassay with a Novel Monoclonal Antibody
Authors: Iwamoto Takaaki , Brooks Philip J. , Nishiwaki Tomohisa , Nishimura Kazuki , Kobayashi Nobuhiko , Sugiura Shigeki , Mori Toshio
Published: January 2014

Xeroderma pigmentosum (XP) is a genetic disorder associated with defects in nucleotide excision repair, which eliminates a wide variety of helix‐distorting types of DNA damage including sunlight‐induced pyrimidine dimers. In addition to skin disease, approximately 30% of XP patients develop progressive neurological disease, which has been hypothesized to be associated with the accumulation of a particular type of oxidatively generated DNA damage called purine 8,5′‐cyclo‐2′‐deoxynucleosides (purine cyclonucleosides). However, there are no currently available methods to detect purine cyclonucleosides in DNA without the need for DNA hydrolysis. In this study, we generated a novel monoclonal antibody (CdA‐1) specific for purine cyclonucleosides in single‐stranded DNA that recognizes 8,5′‐cyclo‐2′‐deoxyadenosine (cyclo‐dA). An immunoassay using CdA‐1 revealed a linear dose response between known amounts of cyclo‐dA in oligonucleotides and the antibody binding to them. The quantitative immunoassay revealed that treatment with Fenton‐type reagents (CuCl2/H2O2/ascorbate) efficiently produces cyclo‐dA in DNA in a dose‐dependent manner. Moreover, immunofluorescent analysis using CdA‐1 enabled the visualization of cyclo‐dA in human osteosarcoma cells, which had been transfected with oligonucleotides containing cyclo‐dA. Thus, the CdA‐1 antibody is a valuable tool for the detection and quantification of cyclo‐dA in DNA, and may be useful for characterizing the mechanism(s) underlying the development of XP neurological disease.
Immunohistochemical staining patterns of cytokeratins 13, 14, and 17 in oral epithelial dysplasia including orthokeratotic dysplasia
Authors: Nobusawa Aiko , Sano Takaaki , Negishi Akihide , Yokoo Satoshi , Oyama Tetsunari
Published: January 2014

Diagnosis of the exact grade of oral epithelial dysplasia is difficult, and interobserver variations in grading are common. The aim of this study was to investigate the expression patterns of cytokeratins (CKs) in dysplastic oral epithelia, to identify useful double immunostaining diagnostic markers. Immunoexpression of CK13, CK14, CK17, and Ki‐67 were investigated in 21 normal epithelial specimens and 146 epithelial dysplasia specimens. In epithelial dysplasia specimens, orthokeratotic dysplasia (OKD) was identified using CK10 immunostaining. Most mild dysplasia specimens were CK13+ and CK17–. In moderate dysplasia, CK13 expression tended to be lower and CK17 expression tended to be higher than in mild dysplasia. All carcinoma in situ (CIS) specimens were CK17+. In differentiated type CIS specimens, CK13 expression was weakly positive. Most epithelial dysplasia specimens were CK14+. There were no significant differences in the expression patterns of CKs between OKD and non‐OKD specimens in any of the grades of dysplasia. These results indicate that CK14 expression can be used to detect early epithelial dysplasia, and that CK13 and CK17 expression are useful for detecting neoplastic changes.
Intraductal dissemination of papillary adenocarcinoma of the ampulla of Vater in the pancreatic duct
Authors: Matsubara Akiko , Nara Satoshi , Sekine Shigeki , Ojima Hidenori , Kosuge Tomoo , Shimada Kazuaki , Kushima Ryoji , Kanai Yae , Hiraoka Nobuyoshi
Published: January 2014

It has been speculated that intraductal dissemination, via the pancreatic duct, bile duct, or mammary duct, is a unique form of cancer cell spread. However, clinical evidence to confirm this form of dissemination has been lacking. Here we report a case of papillary adenocarcinoma of the ampulla of Vater in which retrograde dissemination to the pancreatic duct was strongly suggested. A 79‐year‐old woman underwent pancreatoduodenectomy for a 22 mm microinvasive papillary adenocarcinoma of the ampulla. Multiple carcinomas in situ were found in the pancreatic duct distant from the ampulla. Seven months later, she underwent a second operation for a recurrent papillary adenocarcinoma at the pancreato‐jejunal anastomosis showing exophytic and expansive growth into the jejunal lumen that connected to an intraductal adenocarcinoma in the pancreatic body. None of these tumors showed invasive growth, or vascular or neural invasion, being separate from each other but sharing identical histological, immunohistochemical, and molecular features; papillary growth, a pancreatobiliary phenotype, the same pattern of genomic loss of heterozygosity, and no mutation of the KRAS, TP53, and GNAS genes. These results imply that this papillary adenocarcinoma of the ampulla of Vater had disseminated to the pancreatic duct in a retrograde manner and recurred in the remnant pancreas.
Virulence and toxin synthesis of an azole insensitive Fusarium culmorum strain in wheat cultivars with different levels of resistance to fusarium head blight
Authors: Serfling A. , Ordon F.
Published: January 2014

Fusarium culmorum causes head blight, produces toxins and reduces yield and quality of cereals. To prevent damage caused by fusarium head blight (FHB), azole fungicides are mainly applied. The occurrence of insensitivity to azoles is a major problem in agriculture. The present study shows that a tebuconazole insensitive strain of F. culmorum can be readily produced in the laboratory, but that the resulting strain of the fungus is of lower fitness in vitro. Insensitivity was confirmed microscopically and by cell viability and metabolic activity. The tebuconazole insensitive strain shows cross insensitivity to nine important azoles. In addition, plants inoculated with the insensitive F. culmorum strain showed no reduction of FHB symptoms and deoxynivalenol (DON) content after tebuconazole treatment, compared to an inoculation with the sensitive strain. Use of wheat cultivars carrying a high resistance level (i.e. cv. Toras) was the most effective method for reducing symptoms and decreasing DON content, independent from the level of fungicide insensitivity of the F. culmorum strain. In conclusion, resistant cultivars and a fungicide mixture which combines different mechanisms of action in fungal metabolism should be applied to avoid fungicide insensitivity of Fusarium spp. in future.
Intermediate Filament Proteins Expression and Carbohydrate Moieties in Trophoblast and Decidual Cells of Mature Cat Placenta
Authors: Fernández PE , Diessler ME , Pachame A , Ortega HH , Gimeno EJ , Portiansky EL , Barbeito CG
Published: January 2014

Contents

The aim of this study was to characterize cytoskeletal intermediate filament proteins and glycoconjugates of syncytiotrophoblast, cytotrophoblast and decidual cells of feline endotheliochorial placenta. Samples from 12 normal pregnant female cats, after 45 ± 5 days of gestation, were obtained removing the uterine horns by hysterectomy. Sections were processed for routine observation and for immunohistochemistry using anticytokeratin, antivimentin and antidesmin antibodies. In addition, lectin histochemistry was performed using a panel of several biotinylated lectins to characterize glycosides expression profile. Cytotrophoblast and syncytiotrophoblast showed immunoreactivity only with acidic and basic cytokeratins. Decidual cells were only positive to vimentin, consistent with their origin from endometrial fibroblasts. Trophoblast expressed a broad population of glycans, highly exposing terminal N‐acetyl glucosamine residues and non‐sialylated galactose and N‐acetyl galactosamine oligomers. Oligosaccharides bound by Phaseolus vulgaris erythroagglutinin were the only highly branched N‐linked residues evidenced in cats, and they were restricted to the syncytium. Unlike results reported on humans, mice and rats on lectin affinity of decidual cells, sialid acids and complex N‐linked oligosaccharides were not demonstrated in cats. Glycosylation of proteins determines many of their final properties, thus becoming essential for the embryo‐maternal dialogue during implantation and placentation. Changes in glycosylation pattern have been related to pathological pregnancies in other species. Hence, the knowledge about glycosylation profile of the normal cat placenta may lead to a better understanding of both normal and pathological reproductive events.
A Class of Social Welfare Functions That Depend on Mean Income and Income Polarization
Authors: Rodríguez Juan Gabriel
Published: January 2014

A well‐established strategy for evaluating alternative income distributions is based on the use of an abbreviated social welfare function that depends only on mean income and an inequality index. In keeping with this literature, we study the existence of social welfare functions that can be written as a trade‐off between efficiency and income polarization. This paper proposes a class of social welfare functions consistent with theEsteban andRay, and Duclos, Esteban and Ray income polarization indices. For this result, we expand the domain for personal preferences to incorporate not only own income but also the well‐being of others. In addition, we link our proposal to the literature on relative satisfaction. The approach is illustrated by an empirical application using theCPSdatabase for theUnitedStates in the period 1991–2010.
Envy and egalitarianism in Aboriginal Australia: An integrative approach
Authors: Burbank Victoria
Published: January 2014

The word ‘envy’ directs attention to feelings and cognitions that are especially important sources of information in our complicated sociality. As it is delimited by philosophers, economists, psychologists and others, envy is conceptually nested within a family that includes evil eye beliefs, inequity aversion, strong reciprocity and social comparison. Although the accumulation of work in these areas is substantial, anthropological treatments of envy are rare. Given repeated assertions of envy's universality and its potential importance for understanding widespread aspects of the human condition, a comparative eye seems essential. I present an account of ‘jealous’ in Aboriginal Australia via a framework that casts emotions as emerging from the interaction of psychobiological and sociocultural processes. According to this perspective, ‘envy’ should not be regarded as an invariant human condition but rather as a Western version of what, in a more generic human form, may both defend the individual and the larger sociality.
Evaluation of ABCG2 and p63 expression in canine cornea and cultivated corneal epithelial cells
Authors: Morita Maresuke , Fujita Naoki , Takahashi Ayaka , Nam Eun Ryel , Yui Sho , Chung Cheng Shu , Kawahara Naoya , Lin Hsing Yi , Tsuzuki Keiko , Nakagawa Takayuki , Nishimura Ryohei
Published: January 2014

Objective

To examine the expressions of ABCG2 and p63 in canine corneal epithelia and to evaluate their significance in corneal regeneration.

Procedures

Canine corneal and limbal epithelial cells were obtained from five healthy beagle dogs. We analyzed the morphological properties of cultivated limbal and corneal epithelial cells. We compared the expressions of ABCG2 and p63 in the limbus and central cornea by immunohistochemistry and real‐time quantitative PCR. We analyzed the expression of these markers in cultivated cells by immunocytochemistry and real‐time quantitative PCR.

Results

The limbal epithelial cells were smaller and proliferated more rapidly than the corneal epithelial cells in primary cultures. The corneal cells failed to be subcultured, whereas the limbal cells could be subcultured with increasing cell size. ABCG2 was localized in the basal layer of the limbal epithelium, and p63 was widely detected in the entire corneal epithelia. ABCG2 expression was significantly higher, and p63 was slightly higher in the limbus compared with the central cornea. ABCG2 was detected only in limbal cells in primary culture, not in corneal cells or passaged limbal cells. p63 was detected in both limbal and corneal cells and decreased gradually in the limbal cells with the cell passages.

Conclusions

ABCG2 was localized in canine limbal epithelial cells, and p63 was widely expressed in canine corneal epithelia. ABCG2 and p63 could prove to be useful markers in dogs for putative corneal epithelial stem cells and for corneal epithelial cell proliferation, respectively.
Gas Turbine Modeling for Diagnosis and Control
Authors: Larsson Emil , Åslund Jan , Frisk Erik , Eriksson Lars
Published: January 2014

The supervision of performance in gas turbine applications is crucial in order to achieve: (i) reliable operations, (ii) low heat stress in components, (iii) low fuel consumption, and (iv) efficient overhaul and maintenance. To obtain a good diagnosis of performance it is important to have tests which are based on models with high accuracy. A main contribution is a systematic design procedure to construct a fault detection and isolation (FDI) system for complex nonlinear models. To fulfill the requirement of an automated design procedure, a thermodynamic gas turbine package (GTLib) is developed. Using the GTLib framework, a gas turbine diagnosis model is constructed where component deterioration is introduced. In the design of the test quantities, equations from the developed diagnosis model are carefully selected. These equations are then used to implement a constant gain extended Kalman filter (CGEKF)-based test quantity. The test quantity is used in the FDI-system to supervise the performance and in the controller to estimate the flame temperature. An evaluation is performed using experimental data from a gas turbine site. The case study shows that the designed FDI-system can be used when the decision about a compressor wash is taken. Thus, the proposed model-based design procedure can be considered when an FDI-system of an industrial gas turbine is constructed.
Cascade Utilization of Fuel Gas Energy in Gas-to-Liquids Plant
Authors: Deng Shimin , Hynes Rory
Published: January 2014

This paper investigates on a gas-to-liquids (GTL) plant with ATR syngas production and proposes a new process to use a gas turbine and waste heat recovery gas/steam streams preheater to replace the fired heater. The new process features cascade utilization of fuel gas energy, as fuel gas is firstly used in a gas turbine (GT) at very high temperature and then lower-temperature GT exhaust gas is further used for preheating. Large exergy loss of heat transfer in the fired heater is eliminated. The improved process has an equivalent power generation efficiency of 80% which is significantly higher than conventional technology. Economic analysis indicates 129.8 M$ revenue would be produced over the lifetime if the extra power from a 15,000 bbl/d GTL plant can be exported to the grid at the price of cost of electricity for a conventional natural gas fired combined cycle plant.
Unsteady Work Transfer Within a Turbine Blade Row Passage
Authors: Rose Martin G. , Marx Martin
Published: January 2014

There is evidence in the literature of strong static pressure pulsation on the suction and pressure sides of turbine aerofoil rows experiencing unsteady wake interaction from upstream blade rows. This evidence is both computational and experimental. It has been proposed that this unsteady pulsation causes an unsteady work transfer between the wake and free-stream fluid. It has also been proposed that such a work transfer process may cause a reduction in downstream mixing losses and, thus, an improvement in turbine efficiency. While the literature has provided evidence of the existence of such pulsations, there is no clear explanation of why they occur. This paper addresses the above topic from an analytic perspective; a one-dimensional, incompressible, linear solution to the governing differential equation is used to shed light on this behavior. While the model lacks a lot of physical detail, the pulsation effect is captured, and it is shown that the unsteady pressure attenuates the amplitude of the unsteady total pressure through the transfer of work. The significance of reduced frequency is also clearly demonstrated with convection dominated flow at low reduced frequency and unsteady work dominated flow at high reduced frequencies. The model allows the specification of the amplitude and phase of the down stream static pressure perturbation. This variability is shown to have a significant effect on the attenuation of the unsteady total pressure. New insight is provided in to the much studied topic of “clocking” in axial turbines.
Hemodynamics of Various Configuration Stenting for Bifurcation Aneurysms
Authors: Kono Kenichi , Terada Tomoaki
Published: January 2014

Stent-assisted coil embolization (SACE) is performed for complex aneurysms. There are several configurations of stenting for bifurcation aneurysms. Using computational fluid dynamics (CFD) simulations, we investigated hemodynamics among 8 different configurations of stent placement, which may relate to the recanalization rate.
The Impact of Mesh Implantation on Vaginal Smooth Muscle Innervation and Contraction
Authors: Jallah Zegbeh C. , Moalli Pamela , Feola Andrew , Barone William , Palcsey Stacy , Yoshimura Naoki , Abramowitch Steven D.
Published: January 2014

Pelvic organ prolapse (POP) is a multifactorial disorder characterized by the descent of the pelvic organs into the vaginal canal. This disorder is associated with decreased quality of life, and even depression, yet 50% of women over the age of fifty are living with POP. The cost associated with the repair of POP exceeds one billion dollars annually, in the United States alone. This rather exorbitant figure includes the cost of surgery performed for symptom management, but does not include strategies which address the underlying cause of the disorder for which there are none. Because failure rates of native tissue repairs are as high as 30%, vaginal mesh is increasingly used in the surgical repair of POP. The procedure aims to reinforce the fibromuscular layer of the vagina and the paravaginal attachments, thus providing structural integrity to the weakened native tissues. However, the use of mesh is limited by mesh-related complications including exposure, erosion, pain contraction and infection.
Effect of Fatigue Loading on Tendon Fascicle Extension Mechanisms
Authors: Thorpe Chavaunne T. , Birch Helen L. , Clegg Peter D. , Screen Hazel R. C.
Published: January 2014

Tendon injury is common, probably occurring due to accumulation of microdamage within the tendon matrix as a result of repetitive loading rather than as a sudden onset condition 1. The human Achilles tendon is highly susceptible to injury; this tendon functions as an energy store and experiences high stresses and strains during normal use 2. The equine superficial digital flexor (SDFT) is also an energy storing tendon and is highly injury prone, therefore it is often used as a model to study structure function relationships within this type of tendon 3. Our previous work has characterized the microstructural response of SDFT fascicles to applied strain, with results indicating the presence of a helical component to the fascicle which may facilitate extension by unwinding of the coil 4. The aim of this study was to assess the effect of cyclic fatigue loading (creep) on the microstructural strain response of the equine SDFT to test the hypothesis that fatigue loading would result in altered fascicle extension mechanisms.
Local Anisotropic Mechanical Behavior of Human Carotid Atherosclerotic Plaques: Characterization Using Indentation Test and Inverse Finite Element Analysis
Authors: Chai Chen-Ket , Akyildiz Ali C. , Speelman Lambert , Gijsen Frank J. H. , Oomens Cees W. J. , van Sambeek Marc R. H. M. , van der Lugt Aad , Baaijens Frank P. T.
Published: January 2014

Atherosclerosis is a disorder of the arterial wall. The vessel wall is invaded by lipids and inflammatory cells which can lead to thickening of the arterial wall and eventually to formation of a vulnerable atherosclerotic plaque. Such a vulnerable plaque consists of intraplaque hemorrhage, inflammatory cells, a lipid rich necrotic core (LRNC) and a thin fibrous cap separating the thrombogenic LRNC from the blood stream. The thin fibrous cap is prone to rupture, which can cause thrombus formation and subsequent embolization of thrombus into distal vessels or acute occlusion. This is the major cause of stroke and myocardial infarction.
Energy Storing and Positional Tendon Fascicles Exhibit Different Fatigue Behaviour
Authors: Shepherd J. H. , Legerlotz K. , Demirci T. , Klemt C. , Riley G. P. , Screen H. R. C.
Published: January 2014

Overuse tendinopathies are often considered to be the result of repeated microstrain below the failure threshold, analogous to the fatigue failure of materials under repeated loading [1, 2]. Investigation of tendon overuse in vitro is thus of potential benefit towards characterizing the progression of damage.
Uvula Dynamic Characteristics
Authors: Al-Jumaily A. M. , Ashaat S. , Martin B. A. , Heinzer R. , Haba Rubio J. , Stergiopulos N.
Published: January 2014

The airway binary fluid layer and the structural characteristics of the upper airways have significant influence on the activity of the airway muscles by changing airway compliance and collapsibility during obstructive sleep apnea trauma. The uvula plays an important role in the collapse process. Using MRI scans, this paper develops a structural model for the uvula and determines its dynamic characteristics in terms of natural frequencies and mode shapes as a preliminary process to determine optimum conditions to therapeutically relieve upper airway obstruction. The effect of the variation of tissue elasticity due to water content is elaborated on.
Incorporation of Stress-Dependency in the Modeling of Midpalatal Suture Behavior During Maxillary Expansion Treatment
Authors: Romanyk D. L. , Liu S. S. , Lipsett M. G. , Lagravere M. O. , Toogood R. W. , Major P. W. , Carey J. P.
Published: January 2014

In order to widen a patient’s upper jaw, or maxilla, orthodontists will make use of a maxillary expansion (ME) appliance. This procedure is typically used in adolescents having a narrow maxillary complex. Widening the jaw may be achieved through a variety of means such as expansion screws or springs [1]; however, they are all utilized to generate additional space allowing for correction of various tooth misalignments. An example of a common appliance is provided in Fig. 1a.
Correlation Between Age and Tendon Strength in Supraspinatus Tendon With Full-Thickness Tears
Authors: Miller R. Matthew , Araki Daisuke , Fujimaki Yoshimasa , Musahl Volker , Debski Richard E.
Published: January 2014

Degenerative tears of the rotator cuff tendons are a significant clinical problem, with an incidence of more than 30% in asymptomatic persons over the age of 60 [1]. As the population continues to age, the incidence of partial and full-thickness rotator cuff tears continues to increase [2], with previous studies finding that greater age also correlates with worse surgical outcomes and increased fatty degeneration in the tissue [3]. Although the relationship between age, rotator cuff injury, and poor treatment outcomes has been previously established, insufficient information exists on the biological and mechanical changes in the tissue due to aging.
Anisotropic Behavior of White Matter in Shear and Implications for Transversely Isotropic Models
Authors: Okamoto Ruth J. , Feng Yuan , Genin Guy M. , Bayly Philip V.
Published: January 2014

Experimental studies [1] have shown that white matter (WM) in the brain is mechanically anisotropic. Based on its fibrous structure, transversely isotropic (TI) material models have been suggested to capture WM behavior. TI hyperelastic material models involve strain energy density functions that depend on the I4 and I5 pseudo-invariants of the Cauchy-Green strain tensor to account for the effects of stiff fibers. The pseudo-invariant I4 is the square of the stretch ratio in the fiber direction; I5 contains contributions of shear strain in planes parallel to the fiber axis. Most, if not all, published models of WM depend on I4 but not on I5.
Biomechanics of Reverse Total Shoulder Arthroplasty
Authors: Henninger Heath B. , Burks Robert T. , Tashjian Robert Z.
Published: January 2014

Reverse total shoulder arthroplasty (rTSA) provides significant pain relief and functional improvement in patients with a deficient rotator cuff, 4-part proximal humerus fracture, inflammatory arthritis or revision arthroplasty.[1, 2] As a non-anatomic procedure, rTSA transposes the ball and socket in the glenohumeral joint, allowing the deltoid to initiate elevation of the arm, provide stability and minimize shear forces acting at the glenoid surface.[3, 4]
Using Journal Clubs to Teach Biomechanics: A Two-Year Review
Authors: Kuxhaus Laurel
Published: January 2014

In a biomechanics course, the students often have diverse backgrounds from across the various STEM disciplines. For example, in the course studied at Clarkson University, the average enrollment was 32 students per year (over four years), including an average of 5% graduate students. This population of students included 40% Mechanical Engineering students; 44% Chemical Engineering students; and 15% other engineering/science majors.
Effect of Temperature and Cryoprotectant Solutes on Water Permeability of SF21 Cell Membrane
Authors: Wang Jianye , Zhu Kaixuan , Zhao Gang , Gao Dayong
Published: January 2014

Insect cell as a host of viruses is extensively used for producing heterologous recombinant proteins. The eukaryotic proteins expressed by the insect cell is posttranslationally modified and harvested in a short period of time. The insect cell expression has been applied to both basic research and commercial applications. A large scale of proteins produced by the insect cell expression system are settled for researching the structure and function of the eukaryotic proteins, and the expression system integrated with routine biochemical techniques plays a significant role in diagnostic procedure and therapeutic approaches for the disease.
A Flow-Controlled Finite Element Model of Noncommunicating Hydrocephalus
Authors: Hendra William R. , Lefever Joel A. , García José J. , Smith Joshua H.
Published: January 2014

Cerebrospinal fluid (CSF) is produced at a constant rate in the choroid plexuses of the lateral and third ventricles, and it predominately drains through the Sylvius aqueduct to the fourth ventricle. If the Sylvius aqueduct becomes obstructed, such as caused by a growing tumor adjacent to it, CSF accumulates in the ventricles and the ventricles expand significantly, leading to a medical condition known as noncommunicating, hydrocephalus.
Bioabsorbable Cross Pin vs Endobutton for ACL Reconstruction: A Biomechanical Study in Porcine Model
Authors: Roesler Carlos Rodrigo de Mello , Pizzolatti André Luiz Almeida , Fancello Eduardo , Moré Ari Digiacomo Ocampo
Published: January 2014

Purpose: The aim of this study was to compare the biomechanical performance between Cross Pin and EndoButton methods of graft fixation in femur portion of anterior cruciate ligament (ACL) reconstruction. Methods: Twenty porcine femur, 10 for Biosteon Cross Pin and 10 for EndoButton, were submitted to cyclic loading between 50 N to 250 N for 1000 cycles at 1 Hz. For devices that not failed during cyclic loading, a tensile test to failure was performed at strain rate of 50 mm/min. Results: There were no differences in the cyclic loading test and ultimate failure load between Cross Pin and EndoButton. However, the Cross Pin was stiffer than EndoButton. Results: The Cross Pin shows to be a better option than EndoButton when tested on porcine knee model according the methodology present in this work.
RescuShell: A Biomechanical Design Epistemic Game for First-Year Engineering Education and Potentially Increased Retention of Women
Authors: Tetrick Dan E. , Farley Daniel , Arastoopour Golnaz , Zinn Michael , Shaffer David Williamson , Chesler Naomi C.
Published: January 2014

The American engineering workforce lacks the size and diversity needed to maintain its place as the world leader in science and technology. Across the United States, academic institutions are attempting to retain men and especially women in engineering degree paths by providing introductory coursework that motivates them to persist to graduation. Epistemic games provide students with an authentic engineering experience that may increase their persistence towards engineering degrees. This authentic experience, which we refer to as a virtual internship, helps students create an engineering epistemic frame, in which their skills and knowledge are linked a developing engineering identity, values, and epistemology. RescuShell is an epistemic game that was developed to provide this virtual internship experience for first-year engineering students and increase the persistence of women. In RescuShell, students complete a biomechanical engineering design project in which they create an arm joint for a human enhancement suit. Students research the joint’s actuators, control sensors, power sources, types of articulation, and materials. Completed designs are assessed by the company’s various stakeholders for their ability to meet thresholds for safety, agility, payload, work capacity, reliability, and cost. We anticipate that RescuShell will motivate more men and women to persist to engineering degrees and future careers in the engineering profession than traditional first-year engineering coursework.
Evaluation of Shoulder Stiffness
Authors: Patterson Rita M. , Longnecker Robert , Young Carolyn , Rockenbach Katelyn , Connors Michael
Published: January 2014

Shoulder-related pain in the general adult population has been estimated to be between 6.9 and 26% (potentially 1 in 4 people will experience shoulder dysfunction in their lifetime). Thirty age and gender matched subjects were tested using a specially designed device to measure torque during internal/external shoulder rotation. Subjects with shoulder pain had a decreased shoulder range of motion and increased torque at full internal and external rotation. This device was able to objectively distinguish the amount of stiffness between two populations of subjects.
Numerical Investigation of a Novel Microfluidic System and its Application in Achieving Ultra-Fast Cooling/Warming Rates for Cell Vitrification Cryopreservation
Authors: Zhou Xiaoming , Liang Xin , Shu Zhiquan , Du Pingan , Gao Dayong
Published: January 2014

Background: During conventional cryopreservation, cells are often damaged by ice formation. An alternative approach is to use ultra-rapid cooling rates to achieve vitrification of cell suspension. A variety of systems and methods have been developed, e.g. open pulled straws (OPS), closed pulled straws (CPS), cryo-loop and micro-droplets, by which cooling/warming rates up to 104∼105 °C/min can be achieved[1]. Although these methods have been well used in some areas, they are still far from perfect because (1) the cooling/warming rates are still not fast enough and thus high-concentration cryoprotectants should be used; (2) the sample size is often seriously limited.
Cartilage Contact Mechanics Following Treatment of Acetabular Retroversion With Peri-Acetabular Osteotomy: A Case Study
Authors: Abraham Christine L. , Weiss Jeffrey A. , Peters Christopher L. , Anderson Andrew E.
Published: January 2014

Acetabular retroversion is a form of dysplasia where the acetabulum is tilted excessively in the anterior plane with a loss of posterior coverage. Excessive anterior coverage may cause impingement, and reduced acetabular coverage may increase cartilage contact pressures in the posteroinferior region, thereby causing hip osteoarthritis (OA). Treatment of retroversion is controversial: patients receive debridement of the anterior acetabular rim or posteriorly directed reorientation of the acetabulum via peri-acetabular osteotomy (PAO). Improved methods to quantify pre- and post-operative cartilage mechanics could be used to standardize treatment.
GPU-Based Algorithm for Fast Computation of Cartilage Contact Patterns During Simulations of Movement
Authors: Choi Kwang Won , Negrut Dan , Thelen Darryl G.
Published: January 2014

Direct measurement of cartilage contact is not feasible, necessitating the use of musculoskeletal models to estimate the internal soft tissue loading associated with movement2. However, current computational models used to simulate movement often utilize simplified joint kinematic constraints which can only provide an estimate of the net joint reaction force1. Detailed finite element models of the knee have been created14 which can provide estimates of cartilage tissue stress, but are too computationally expensive to solve within the context of a whole body simulation of movement. Discrete element analysis (DEA) provides a viable alternative for rapidly computing contact stress patterns in movement15, However, even DEA models can be computationally expensive as high resolution polygonal meshes are needed to accurately represent complex cartilage geometries such as that seen on the femoral condyles and tibia plateau. In a DEA model, much of the computation time is spent querying for contact between triangles of two polygonal surfaces. The objective of this study was to investigate the potential for using graphic processor computation (GPU) to expedite contact detection5. To do this, we use a contact detection algorithm that pre-constructs hierarchical bounding-volumes (BVH) of the target body to increase the efficiency of contact detection. We then show that implementing a parallel computational version of this algorithm on the GPU greatly speed up performance and thus make it more viable to simulate cartilage contact within the context of human movement.
Reducing the Osmotic Damage of RBCs During the Removal of CPAs From Cryopreserved Blood by the Dilution-Concentration Method: Extended Dilution Region
Authors: Gong Liangquan , Ding Weiping , Sun Sijie , Zhao Gang , Gao Dayong
Published: January 2014

In this work, the dilution-concentration method proposed in our previous work is optimized to reduce the osmotic damage of red blood cells during the process of removing cryoprotective agents from cryopreserved blood. In the optimization, the dilution region i.e. the tubing length from the dilution point to the concentration point is extended so that the negative accumulation effect of the volume change of red blood cells can be allivated. By doing this, the volume maximum of red blood cells experienced during the removal of cryoprotective agents can be decreased and thereby the osmotic damage of red blood cells can be reduced.
Can We Use In Vivo MRI and FEA to Determine Peak Cap Stress in Carotid Plaques? MRI Simulations Provide Answers
Authors: Nieuwstadt Harm A. , Wentzel Jolanda W. , van der Lugt Aad , van der Steen Anton F. W. , Breeuwer Marcel , Gijsen Frank J. H.
Published: January 2014

Vulnerable plaques are characterized by a large lipid-rich necrotic core (LRNC) separated by a thin fibrous cap (FC) from the lumen. Plaque rupture occurs when the peak stress in the FC exceeds its strength. Carotid in vivo magnetic resonance imaging (MRI) data can be segmented to obtain the plaque geometry noninvasively. An increasing number of studies use MR imaging for biomechanical finite element analysis (FEA) to compute peak cap stresses [1, 2]. Previous studies have shown that the thickness of the FC is an important determinant of peak cap stress: the thinner the FC, the higher the stress, the higher the plaque rupture risk [3].
Parameters Influencing Distal Tip Loading of Pacemaker and Defibrillator Leads
Authors: Walsh Donna , Stephen Beth , Duraiswamy Nandini , Vesnovsky Oleg , Topoleski L. D. Timmie
Published: January 2014

More than 235,000 pacemakers and 130,000 implantable cardioverter defibrillators (ICD) were implanted in the United States in 2009 [1] for the treatment of various cardiac arrhythmias. Traditional pacemakers and ICDs deliver therapy to the patient through a transvenous lead that extends from a subcutaneously-implanted pulse generator, through the subclavian or cephalic vein, the superior vena cava (SVC), and into the heart. Attachment of the distal tip of the lead into the cardiac muscle is accomplished through either an active fixation mechanism where a metal helix is screwed into the cardiac wall at the time of implantation, or a passive fixation mechanism where silicone tines are ensnared by the fibrous trabeculae within the heart. Implantation of both active and passive leads is aided by the insertion of a stylet, or thin wire, into the lead to provide additional stiffness and steerability as the device is pushed through the vasculature and to the implant site.
The Impact of Tissue Viscoelasticity on the Flow Dynamics of an Anti-HIV Microbicidal Gel: Numerical Simulations
Authors: Talbi Zouhair , Kieweg Sarah L.
Published: January 2014

Coating vaginal or rectal epithelium using microbicidal gels is a promising preventive procedure against HIV and other sexually transmitted infections (STIs). A microbicidal gel is deployed as a delivery vehicle of anti-HIV and other anti-STI agents and it is also used to act as barrier between the pathogens and the biological tissue. The efficacy of a microbicidal gel depends greatly on the extent of the spreading and the amount of the epithelial surfaces covered.
Bagging Device for One Handed Users
Authors: Porter Aaron , McKee Haley , Fischer Kenneth J. , Dougherty Ronald L.
Published: January 2014

Accommodations for disabilities in the workplace have improved significantly in recent years. Despite these improvements, an analysis [1] found that only “15.6% of workers with disabilities report needing accommodations, and 12.2% report receiving them.” Cottonwood Industries was founded in 1972 and is located in Lawrence, KS. A variety of jobs such as labeling, textiles, medical, and packaging are completed by employees. A large portion of the 140 person workforce at Cottonwood Industries is limited by physical and/or mental disabilities. Of these disabilities, 10 workers have full use of only one hand and struggle daily with simple tasks such as packaging. Manager, Steve Steinbach, identified a strong need for a device which would assist these workers by reducing frustration and speeding up the packaging process for them.
Finite Element Predictions of Joint Contact Mechanics and Acetabular Curvature in Dysplastic Human Hips
Authors: Henak Corinne R. , Abraham Christine L. , Anderson Andrew E. , Peters Christopher L. , Maas Steve A. , Ellis Benjamin J. , Weiss Jeffrey A.
Published: January 2014

Acetabular dysplasia is characterized by a shallow acetabulum and is believed to cause accelerated hip osteoarthritis (OA) via altered mechanics (Fig. 1 A, B) [1]. Dysplastic acetabula are also described as more flat and less congruent than normal acetabula [2]. However, the relative contributions of altered labrum and cartilage contact mechanics, as well as quantitative differences in curvature are poorly understood in the dysplastic hip compared to the normal hip. Clinical observations of hypertrophied and damaged labra indicate altered labrum mechanics in dysplastic hips [3]. Finite element (FE) studies demonstrate abnormal cartilage mechanics in dysplastic hips, but are limited to models that omit the labrum or utilize idealized joint geometry (e.g., [4]). Therefore, the objectives of this study were to compare contact mechanics and curvature between normal and dysplastic hips using subject-specific FE models.
Phototherapy Enhanced Exclusion of Aneurysms From the Cerebral Circulation
Authors: Lieber Baruch B. , Sadasivan Chander , Fiorella David J. , Woo Henry H.
Published: January 2014

Accumulated experience using flow diverters in humans suggests that complete cure of the aneurysm is usually a protracted process that can last up to twelve months [1]. While it is well established that a properly designed flow diverter serves as a scaffold for neointimal proliferation, the process of its formation over the aneurysm neck is delayed until the aneurysm cavity itself is occluded by a thrombus, negating flow of fresh blood through the neck, and thus allowing the neointimal formation to bridge the aneurysm neck. The notion that induction of some injury to the luminal surface of the aneurysmal tissue, particularly to the endothelium, may result in a healing response that is faster than just placing a flow diverter and waiting for thrombus formation within the aneurysm has been tried in the past using various experimental models. Some of the injuries to the aneurysm tissue that have been tried in the past include mechanical scraping, thermal heating and UV irradiation. All these attempts, while showing that hastening the thrombus formation is feasible, have not resulted in any success due to the fact that the processes that were tried suffered from lack of proper control to be implemented in actual aneurysmal tissue that is weakened and diseased a priori.
Analysis of Human Accident Video Using Optical Flow With Physically-Based Constraints
Authors: Zwart Christine , Frakes David , Singhose William
Published: January 2014

Videos that capture accidents are usually of poor quality: they are likely to be taken from a bad angle, with poor lighting, and contain occluded points. However, the motion data contained in such videos can be very valuable for understanding and preventing accidents. To extract the motion of a body from a video: 1) the points of interest must be identified and 2) point tracking from frame-to-frame must be accomplished. Accordingly, one logical approach is to focus on automated tracking, while allowing a human to identify important points of interest [1].
Determining Optimal Current Intensity and Duration for Electrically Activated Silver-Based Prophylactic Hip Implant Prototype Design
Authors: Tan Zhuo , Shirwaiker Rohan A. , Orndoff Paul E.
Published: January 2014

Infections associated with medical prostheses result in notable morbidity, and traditional osteomyelitis treatments are often accompanied by high risk and cost. The probability of prosthetic joint infections is 1–2.5 % for primary hip or knee replacements and 2.1–5.8 % for revision surgeries, and the cost of treating such an infection is estimated to be over $50,000 per episode. [1] While the potential benefits of silver surfaces stimulated by low intensity direct current (LIDC) have been discussed in literature, we have recently utilized that concept in the actual design of prophylactic indwelling residual hardware prostheses for the very first time. [2–4] A modular titanium hip stem coated with silver at the anode (and titanium as the cathode) and activated by a watch battery encapsulated within the two electrode modules (Figure 1) will result in oligodynamic iontophoresis (OI) in the soft tissue surrounding the implant which is prone to infections. Preliminary in vitro and in vivo results have demonstrated the potency of silver-based OI as an effective local antibacterial therapy in osteomyelitis treatment with advantages over various antibiotics. However, the main challenge here is achieving the antibacterial potency while minimizing any potential toxic effects on local tissues. [4]