bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the ascent: the soleus operating length is conserved to the ascending limb of the force-length curve across gait mechanics in humans
Authors: Rubenson Jonas , Pires Neville J , Loi Hoek O , Pinniger Gavin J , Shannon Damian G 
Published: July 2012

Summary
The region over which skeletal muscles operate on their force-length (F-L) relationship is fundamental to the mechanics, control and economy of movement. Yet, surprisingly little experimental data exist on normalized length operating ranges of muscle during human gait, or how they are modulated when mechanical demands (such as force output) change. Here we explore the soleus muscle (SOL) operating lengths experimentally in a group of healthy young adults by combining subject-specific F-L relationships with in vivo muscle imaging during gait. We test whether modulation of operating lengths occurs between walking and running, two gaits that require different levels of force production and different muscle-tendon mechanics, and examine the relationship between optimal fascicle lengths (L0) and normalized operating lengths during these gaits. We found that the mean active muscle lengths reside predominantly on the ascending limbs of the F-L relationship in both gaits (0.70 - 0.94 L0, walk; 0.65 - 0.99 L0, run). Furthermore, the mean normalized muscle length at the time of the muscle's peak activation was the same between the two gaits (0.88 L0). The active operating lengths were conserved, despite a fundamentally different fascicle strain pattern between walking (stretch-shorten cycle) and running (near continuous shortening). Taken together, these findings indicate that the SOL operating length is highly conserved despite gait-dependant differences in muscle-tendon dynamics, and appear to be preferentially selected for stable force production compared to optimal force output (although length-dependent force capacity is high when maximal forces are expected to occur). Individuals with shorter L0 undergo smaller absolute muscle excursions (p&lt;0.05) so that the normalized length changes during walking and running remain independent of L0. The correlation between L0 and absolute length change was not explained on the basis of muscle moment arms or joint excursion, suggesting that regulation of muscle strain may occur via tendon stretch.
Tendon material properties vary and are interdependent among turkey hindlimb muscles
Authors: Matson Andrew , Konow Nicolai , Miller Samuel , Konow Pernille P. , Roberts Thomas J. 
Published: July 2012

SummaryThe material properties of a tendon affect its ability to store and return elastic energy, resist damage, provide mechanical feedback, and amplify or attenuate muscle power. While the structural properties of tendon are known to respond to a variety of stimuli, the extent to which material properties vary among individual muscles remains unclear. We studied the tendons of six different muscles in the hindlimb of Eastern wild turkeys to determine if there was variation in elastic modulus, ultimate tensile strength, and resilience. A hydraulic testing machine was used to measure tendon force during quasi-static lengthening, and a stress strain curve was constructed. There was substantial variation in tendon material properties among different muscles. Average elastic modulus differed significantly between some tendons, and values for the six different tendons varied nearly two-fold, from 829±140 to 1479±106 MPa. Tendons were stretched to failure, and the stress at failure, or ultimate tensile stress, was taken as a lower-limit estimate of tendon strength. Breaking tests for four of the tendons revealed significant variation in ultimate tensile stress, ranging from 66.83±14.34 MPa to 112.37±9.39 MPa. Resilience, or the fraction of energy returned in cyclic length changes was generally high, and one of the four tendons tested was significantly different in resilience than the other tendons (range: 90.65±0.83 to 94.02±0.71). An analysis of correlation between material properties revealed a positive relationship between ultimate tensile strength and elastic modulus (R2=0.79). Specifically, stiffer tendons were stronger, and we suggest that this correlation results from a constrained value of breaking strain, which did not vary significantly among tendons. This finding suggests an interdependence of material properties that may have a structural basis and may explain some adaptive responses observed in studies of tendon plasticity.
Jumping mechanisms in jumping plant lice (Hemiptera, Sternorrhyncha, Psyllidae)
Authors: Burrows Malcolm 
Published: July 2012

SummaryJumping mechanisms and performance were analysed in three species of psyllids (Hemiptera, Sternorrhyncha) that ranged from 2 to 4 mm in body length and from 0.7 to 2.8 mg in weight. Jumping was propelled by rapid movements of the short hind legs that were only 10-20% longer than the other legs and 61-77% of body length. Power was provided by large thoracic muscles that depressed the trochantera so that the two hind legs moved in parallel planes on either side of the body. These movements accelerated the body to take-off in 0.9 ms in the smallest psyllid and 1.7 ms in the largest, but in all species imparted a rapid forward rotation so that at take-off the head pointed downwards, subtending angles of about -60 degrees relative to the ground. The front legs thus supported the body just before take-off and either lost contact with the ground at the same time as, or even after the hind legs. In the best jumps from the horizontal, take-off velocity reached 2.7 m s-1 and the trajectory was steep at 62-80 degrees. Once airborne the body spun rapidly at rates up to 336 Hz in the pitch plane. In many jumps the wings did not open to provide stabilisation, but some jumps led directly to sustained flight. In their best jumps the smallest species experienced a force of 637 g. The largest species had an energy requirement of 13 µJ, a power output of 13 mW and exerted a force of nearly 10 mN. In a rare jumping strategy seen in only 2 of 211 jumps analysed, the femoro-tibial joints extended further and resulted in the head pointing upwards at take-off and the spin rate being greatly reduced.
Light filtering devices using background wavelength processing techniques
Authors: Vieira M. A. , Vieira M. , Louro P. , Silva V. , Garção A. S. 
Published: July 2012

ABSTRACTThis paper reports on light filtering devices based on a-SiC:H tandem pi´n/pin heterostructures. The spectral sensitivity is analyzed. Steady state optical bias with different wavelengths, are applied from each front and back sides and the photocurrent is measured. Results show that it is possible to control the sensitivity of the device and to tune a specific wavelength range by combining radiations with complementary light penetration depths. The transfer characteristics effects due to changes in the front and back optical bias wavelength are discussed.Input red, green and blue pulsed communication channels are transmitted together, each one in a specific bit sequence and the multiplex signal is analyzed. By superimposing appropriate background and depending on the channel/background wavelength combinations, the device behaves as a long- or a short- pass filter, producing signal attenuation, or as an amplifier, producing signal gain. A physical model is presented to support the filter properties of the device.
When Small is Different: The Case of Membranes Inside Tubes
Authors: Perim Eric , Fonseca Alexandre F. , Galvão Douglas S. 
Published: July 2012

ABSTRACTRecently, classical elasticity theory for thin sheets was used to demonstrate the existence of a universal structural behavior describing the confinement of sheets inside cylindrical tubes. However, this kind of formalism was derived to describe macroscopic systems. A natural question is whether this behavior still holds at nanoscale. In this work, we have investigated through molecular dynamics simulations the structural behavior of graphene and boron nitride single layers confined into nanotubes. Our results show that the class of universality observed at macroscale is no longer observed at nanoscale. The origin of this discrepancy is addressed in terms of the relative importance of forces and energies at macro and nano scales.
Overcoming Resistance to Antiangiogenic Therapies
Authors: Tejpar Sabine , Prenen Hans , Mazzone Massimiliano 
Published: July 2012

Abstract
The concept of targeting new blood vessel formation, or angiogenesis, in tumors is an important advancement in cancer therapy, resulting, in part, from the development of such biologic agents as bevacizumab, a monoclonal antibody directed against vascular endothelial growth factor (VEGF)-A. The rationale for antiangiogenic therapy is based on the hypothesis that if tumors are limited in their capacity to obtain a new blood supply, so too is their capacity for growth and metastasis. Additional evidence suggests that pruning and/or “normalization” of irregular tumor vasculature and reduction of hypoxia may facilitate greater access of cytotoxic chemotherapy (CT) to the tumor. Indeed, for metastatic colorectal cancer, bevacizumab in combination with established CT regimens has efficacy superior to that of CT alone. Despite ∼2-month longer progression-free and overall survival times than with CT alone, patients still progress, possibly because of alternative angiogenic “escape” pathways that emerge independent of VEGF-A, or are driven by hypoxic stress on the tumor. Other VEGF family members may contribute to resistance, and many factors that contribute to the regulation of tumor angiogenesis function as part of a complex network, existing in different concentrations and spatiotemporal gradients and producing a wide range of biologic responses. Integrating these concepts into the design and evaluation of new antiangiogenic therapies may help overcome resistance mechanisms and allow for greater efficacy over longer treatment periods.
Adiponectin and All-Cause Mortality in Elderly People With Type 2 Diabetes
Authors: Singer Jessica R. , Palmas Walter , Teresi Jeanne , Weinstock Ruth , Shea Steven , Luchsinger José A. 
Published: July 2012

OBJECTIVE
To assess the association between serum adiponectin level and all-cause mortality in people with type 2 diabetes. Because of the insulin-sensitizing, anti-inflammatory, and antiatherogenic effects of adiponectin, we hypothesized that higher adiponectin level would be associated with lower all-cause mortality.

RESEARCH DESIGN AND METHODS
A total of 609 men and women aged 72 ± 6.3 years with type 2 diabetes and information on total and high molecular weight adiponectin were followed for a median of 5 years. The longitudinal association between adiponectin and all-cause mortality was analyzed with Cox proportional hazards models with time from adiponectin measurement to death as the time-to-event variable. Analyses were adjusted for demographic variables and significant diabetes parameters, significant cardiovascular parameters, and significant diabetes medications.

RESULTS
Total and high molecular weight adiponectin were highly correlated. The highest adiponectin quartile was strongly associated with higher all-cause mortality compared with the lowest quartile (hazard ratio = 4.0 [95% CI: 1.7–9.2]) in the fully adjusted model. These results did not change in analyses stratified by sex and thiazolidinedione use, after exclusion of people who died within one year of adiponectin measurement, or when change in weight before adiponectin measurement was considered.

CONCLUSIONS
Contrary to our hypothesis, higher adiponectin level was related to higher all-cause mortality. This association was not explained by confounding by other characteristics, including medications or preceding weight loss.
Antenatal Diagnosis of Fetal Genotype Determines if Maternal Hyperglycemia Due to a Glucokinase Mutation Requires Treatment
Authors: Chakera Ali J. , Carleton Victoria L. , Ellard Sian , Wong Jencia , Yue Dennis K. , Pinner Jason , Hattersley Andrew T. , Ross Glynis P. 
Published: July 2012

OBJECTIVE
In women with hyperglycemia due to heterozygous glucokinase (GCK) mutations, the fetal genotype determines its growth. If the fetus inherits the mutation, birth weight is normal when maternal hyperglycemia is not treated, whereas intensive treatment may adversely reduce fetal growth. However, fetal genotype is not usually known antenatally, making treatment decisions difficult.

HISTORY AND EXAMINATION
We report two women with gestational diabetes mellitus resulting from GCK mutations with hyperglycemia sufficient to merit treatment.

INVESTIGATION
In both women, DNA from chorionic villus sampling, performed after high-risk aneuploidy screening, showed the fetus had inherited the GCK mutation. Therefore, maternal hyperglycemia was not treated. Both offspring had a normal birth weight and no peripartum complications.

CONCLUSIONS
In pregnancies where the mother has hyperglycemia due to a GCK mutation, knowing the fetal GCK genotype guides the management of maternal hyperglycemia. Fetal genotyping should be performed when fetal DNA is available from invasive prenatal diagnostic testing.
Textile materials for electromagnetic field shielding made with the use of nano- and micro-technology
Authors: Brzeziński Stefan , Rybicki Tomasz , Karbownik Iwona , Malinowska Grażyna , Śledzińska Katarzyna 
Published: July 2012

Abstract
Studies have been carried out aimed at the development of structures and technology for making special multi-layer textile-polymeric systems of shielding electromagnetic field (EMF). The use of textiles as EMF shielding materials is commonly known, however the EMF attenuation obtained practically exclusively results from the reflection of EMF, while the materials used for this purpose as a rule, show poor EMF absorption abilities. The basic assumption for a new solution is the exploitation of the multiple internal reflection of incident EMF either in textile-polymeric coating materials containing fine-particle electromagnetic materials or in special textile structures. This paper presents the results of investigating the EMF shielding effectiveness of several selected and developed textile-polymeric materials in respect of both their practical applications (protective clothing elements, technical materials, masking elements, etc.) and the structure and content of components with various EMF reflection and absorption properties. The measurement method for independent determination of reflection and transmission coefficients with a wavequide applicator was used. The results obtained with the 2.5 GHz to 18 GHz frequency range show a low value of transmission coefficient (min. −35 dB) and accepted reflection attenuation from about −4 dB to −15 dB for higher frequencies.
Phase space analysis of interacting dark energy in f(T) cosmology
Authors: Jamil Mubasher , Yesmakhanova Kuralay , Momeni Davood , Myrzakulov Ratbay 
Published: July 2012

Abstract
In this paper, we examine the interacting dark energy model in f(T) cosmology. We assume dark energy as a perfect fluid and choose a specific cosmologically viable form f(T) = β√T. We show that there is one attractor solution to the dynamical equation of f(T) Friedmann equations. Further we investigate the stability in phase space for a general f(T) model with two interacting fluids. By studying the local stability near the critical points, we show that the critical points lie on the sheet u* = (c − 1)v* in the phase space, spanned by coordinates (u, v, Ω, T). From this critical sheet, we conclude that the coupling between the dark energy and matter c ∈ (−2, 0).
PACIAE model capability in describing net proton moments
Authors: Limphirat Ayut , Zhou Dai-Mei , Yan Yu-Liang , Dong Bao-Guo , Kobdaj Chinorat , Yan Yupeng , Csernai Laszlo , Sa Ben-Hao 
Published: July 2012

Abstract
PACIAE 2.0, a parton and hadron cascade model, is employed to investigate the dependence of the moments of net proton event distributions on reaction energies varying from RHIC to LHC energy in p + p collisions. It is found that net proton moments and moment products are sensitive to the collision energy except the moment product kσ
2 which is almost independent of the collision energy. The PACIAE results are in line with experimental data.
Metal-on-Metal Total Hip Arthroplasty: Causes and High Incidence of Early Failure
Authors: Fabi David , Levine Brett , Paprosky Wayne , Della Valle Craig , Sporer Scott , Klein Gregg , Levine Harlan , Hartzband Mark 
Published: July 2012

Early failures of metal-on-metal total hip arthroplasty (THA) occur due to aseptic loosening, metal hypersensitivity reactions, pseudotumor formation, and component seizing. The purpose of this study was to investigate the timing, common modes of failure, clinical outcomes, and incidence of metal-on-metal THA revisions.
A review was performed of 80 patients who underwent revision of a failed metal-on-metal THA for any reason. The most common reason for metal-on-metal failure was aseptic acetabular loosening, with a rate of 56.25% (45/80 patients). Early failure of metal-on-metal THAs was noted, with 78% of these revisions being performed within 2 years of the index operation and 92.5% within 3 years. Furthermore, 13% of patients experienced significant localized soft tissue reactions. Mean preoperative Harris Hip Score was 42.35±14.24 and mean postoperative Harris Hip Score was 66.5±23.2 (range, 9.55–95.4), with an average follow-up of 438±492 days (range, 40–2141), or 1.2 years.
It is imperative that clinicians be cognizant of the fact that the proposed advantages of metal-on-metal THA are not without potential detrimental sequelae. This article proposes an algorithm to aid in diagnosing the etiology of a painful metal-on-metal THA, as well as 2 classification schemes regarding metal-on-metal THA complications to help direct treatment.
Mutation at Positively Selected Positions in the Binding Site for HLA-C Shows That KIR2DL1 Is a More Refined but Less Adaptable NK Cell Receptor Than KIR2DL3
Authors: Hilton Hugo G. , Vago Luca , Older Aguilar Anastazia M. , Moesta Achim K. , Graef Thorsten , Abi-Rached Laurent , Norman Paul J. , Guethlein Lisbeth A. , Fleischhauer Katharina , Parham Peter 
Published: July 2012

AbstractThrough recognition of HLA class I, killer cell Ig-like receptors (KIR) modulate NK cell functions in human immunity and reproduction. Although a minority of HLA-A and -B allotypes are KIR ligands, HLA-C allotypes dominate this regulation, because they all carry either the C1 epitope recognized by KIR2DL2/3 or the C2 epitope recognized by KIR2DL1. The C1 epitope and C1-specific KIR evolved first, followed several million years later by the C2 epitope and C2-specific KIR. Strong, varying selection pressure on NK cell functions drove the diversification and divergence of hominid KIR, with six positions in the HLA class I binding site of KIR being targets for positive diversifying selection. Introducing each naturally occurring residue at these positions into KIR2DL1 and KIR2DL3 produced 38 point mutants that were tested for binding to 95 HLA- A, -B, and -C allotypes. Modulating specificity for HLA-C is position 44, whereas positions 71 and 131 control cross-reactivity with HLA-A*11:02. Dominating avidity modulation is position 70, with lesser contributions from positions 68 and 182. KIR2DL3 has lower avidity and broader specificity than KIR2DL1. Mutation could increase the avidity and change the specificity of KIR2DL3, whereas KIR2DL1 specificity was resistant to mutation, and its avidity could only be lowered. The contrasting inflexibility of KIR2DL1 and adaptability of KIR2DL3 fit with C2-specific KIR having evolved from C1-specific KIR, and not vice versa. Substitutions restricted to activating KIR all reduced the avidity of KIR2DL1 and KIR2DL3, further evidence that activating KIR function often becomes subject to selective attenuation.
Identification of Hemopexin as an Anti-Inflammatory Factor That Inhibits Synergy of Hemoglobin with HMGB1 in Sterile and Infectious Inflammation
Authors: Lin Tian , Sammy Fatima , Yang Huan , Thundivalappil Sujatha , Hellman Judith , Tracey Kevin J. , Warren H. Shaw 
Published: July 2012

Abstract
Hemoglobin is released from lysed RBCs in numerous clinical settings. High mobility group box 1 (HMGB1) is a nuclear and cytosolic DNA-binding protein released from injured cells that has been shown to play an important role in inducing inflammation. Because both of these endogenous molecules are frequently present in sites of necrosis and inflammation, we studied their interaction on the activation of macrophages. We report in this article that hemoglobin and HMGB1 synergize to activate mouse macrophages to release significantly increased proinflammatory cytokines. Addition of microbial ligands that activate through TLR2 or TLR4 resulted in further significant increases, in a “three-way” synergy between endogenous and microbial ligands. The synergy was strongly suppressed by hemopexin (Hx), an endogenous heme-binding plasma protein. The findings suggest that hemoglobin may play an important role in sterile and infectious inflammation, and that endogenous Hx can modulate this response. Administration of Hx may be beneficial in clinical settings characterized by elevated extracellular hemoglobin and HMGB1.
Commensal Bacteria Lipoteichoic Acid Increases Skin Mast Cell Antimicrobial Activity against Vaccinia Viruses
Authors: Wang Zhenping , MacLeod Daniel T. , Di Nardo Anna 
Published: July 2012

Abstract
Mast cells (MCs) are considered sentinels in the skin and mucosa. Their ability to release antimicrobial peptides, such as cathelicidin, protects against bacterial infections when the epithelial barrier is breached. We recently described that MCs defend against bacterial and viral infections through the release of cathelicidin during degranulation. In this study, we hypothesize that cathelicidin expression is induced in MCs by the activation of TLR2 from bacterial products (lipoteichoic acid) produced by commensal bacteria at the epithelial surface. Our research shows that signaling through TLR2 increases the production and expression of cathelicidin in mast cells, thereby enhancing their capacity to fight vaccinia virus. MCs deficient in cathelicidin were less efficient in killing vaccinia virus after lipoteichoic acid stimulation than wild-type cells. Moreover, the activation of TLR2 increases the MC recruitment at the skin barrier interface. Taken together, our findings reveal that the expression and control of antimicrobial peptides and TLR signaling on MCs are key in fighting viral infection. Our findings also provide new insights into the pathogenesis of skin infections and suggest potential roles for MCs and TLR2 ligands in antiviral therapy.