bluuebunny/crossref_metadata_2025 huggingface dataset:
Ionic bases for electrical remodeling of the canine cardiac ventricle
Authors: Jeyaraj Darwin , Wan Xiaoping , Ficker Eckhard , Stelzer Julian E. , Deschenes Isabelle , Liu Haiyan , Wilson Lance D. , Decker Keith F. , Said Tamer H. , Jain Mukesh K. , Rudy Yoram , Rosenbaum David S.
Published: May 2013

Emerging evidence suggests that ventricular electrical remodeling (VER) is triggered by regional myocardial strain via mechanoelectrical feedback mechanisms; however, the ionic mechanisms underlying strain-induced VER are poorly understood. To determine its ionic basis, VER induced by altered electrical activation in dogs undergoing left ventricular pacing ( n = 6) were compared with unpaced controls ( n = 4). Action potential (AP) durations (APDs), ionic currents, and Ca2+transients were measured from canine epicardial myocytes isolated from early-activated (low strain) and late-activated (high strain) left ventricular regions. VER in the early-activated region was characterized by minimal APD prolongation, but marked attenuation of the AP phase 1 notch attributed to reduced transient outward K+current. In contrast, VER in the late-activated region was characterized by significant APD prolongation. Despite marked APD prolongation, there was surprisingly minimal change in ion channel densities but a twofold increase in diastolic Ca2+. Computer simulations demonstrated that changes in sarcolemmal ion channel density could only account for attenuation of the AP notch observed in the early-activated region but failed to account for APD remodeling in the late-activated region. Furthermore, these simulations identified that cytosolic Ca2+accounted for APD prolongation in the late-activated region by enhancing forward-mode Na+/Ca2+exchanger activity, corroborated by increased Na+/Ca2+exchanger protein expression. Finally, assessment of skinned fibers after VER identified altered myofilament Ca2+sensitivity in late-activated regions to be associated with increased diastolic levels of Ca2+. In conclusion, we identified two distinct ionic mechanisms that underlie VER: 1) strain-independent changes in early-activated regions due to remodeling of sarcolemmal ion channels with no changes in Ca2+handling and 2) a novel and unexpected mechanism for strain-induced VER in late-activated regions in the canine arising from remodeling of sarcomeric Ca2+handling rather than sarcolemmal ion channels.
Increased vascular smooth muscle cell stiffness: a novel mechanism for aortic stiffness in hypertension
Authors: Sehgel Nancy L. , Zhu Yi , Sun Zhe , Trzeciakowski Jerome P. , Hong Zhongkui , Hunter William C. , Vatner Dorothy E. , Meininger Gerald A. , Vatner Stephen F.
Published: May 2013

Increased vascular stiffness is fundamental to hypertension, and its complications, including atherosclerosis, suggest that therapy should also be directed at vascular stiffness, rather than just the regulation of peripheral vascular resistance. It is currently held that the underlying mechanisms of vascular stiffness in hypertension only involve the extracellular matrix and endothelium. We hypothesized that increased large-artery stiffness in hypertension is partly due to intrinsic mechanical properties of vascular smooth muscle cells. After confirming increased arterial pressure and aortic stiffness in spontaneously hypertensive rats, we found increased elastic stiffness of aortic smooth muscle cells of spontaneously hypertensive rats compared with Wistar-Kyoto normotensive controls using both an engineered aortic tissue model and atomic force microscopy nanoindentation. Additionally, we observed different temporal oscillations in the stiffness of vascular smooth muscle cells derived from hypertensive and control rats, suggesting that a dynamic component to cellular elastic stiffness is altered in hypertension. Treatment with inhibitors of vascular smooth muscle cell cytoskeletal proteins reduced vascular smooth muscle cell stiffness from hypertensive and control rats, suggesting their participation in the mechanism. This is the first study demonstrating that stiffness of individual vascular smooth muscle cells mediates vascular stiffness in hypertension, a novel concept, which may elucidate new therapies for hypertension and for vascular stiffness.
Rats selectively bred for differences in aerobic capacity have similar hypertensive responses to chronic intermittent hypoxia
Authors: Sharpe Amanda L. , Andrade Mary Ann , Herrera-Rosales Myrna , Britton Steven L. , Koch Lauren G. , Toney Glenn M.
Published: May 2013

Exposure to chronic intermittent hypoxia (CIH) is an animal model that mimics the repetitive bouts of hypoxemia experienced by humans with sleep apnea. Rats exposed to CIH develop hypertension that depends on the activation of sympathetic nerve activity (SNA). Since obesity and metabolic syndrome have been linked to neurogenic hypertension and sleep apnea, and because sleep apnea can adversely affect aerobic exercise capacity, we tested the hypothesis that rats bred for selection of low aerobic capacity running (LCR) would have a greater hypertensive response to CIH than rats bred for high aerobic capacity running (HCR). Blockade of ganglionic transmission was performed to compare the contribution of SNA to the maintenance of resting mean arterial pressure (MAP). Next, hypertensive responses to 7 days of CIH were compared across LCR and HCR rats (14–16 mo old). Finally, the contribution of the hypothalamic paraventricular nucleus (PVN) to the maintenance of SNA and hypertension after CIH was determined and compared across groups. Although LCR rats were less active and had greater body weights than HCR rats, resting MAP, the contribution of ongoing SNA to the maintenance of MAP, and hypertensive responses to CIH were similar between groups. Contrary to our hypothesis, chemical inhibition of the PVN with muscimol (1 mmol/100 nl) caused a larger fall of MAP in HCR rats than in LCR rats. We conclude that LCR rats do not have resting hypertension or an exaggerated hypertensive response to CIH. Interestingly, the maintenance of CIH hypertension in LCR rats compared with HCR rats appears less reliant on ongoing PVN neuronal activity.
Autophagy: a potential therapeutic target in lung diseases
Authors: Nakahira Kiichi , Choi Augustine M. K.
Published: May 2013

Macroautophagy (hereafter referred to as autophagy) is an evolutionally conserved intracellular process to maintain cellular homeostasis by facilitating the turnover of protein aggregates, cellular debris, and damaged organelles. During autophagy, cytosolic constituents are engulfed into double-membrane-bound vesicles called “autophagosomes,” which are subsequently delivered to the lysosome for degradation. Accumulated evidence suggests that autophagy is critically involved not only in the basal physiological states but also in the pathogenesis of various human diseases. Interestingly, a diverse variety of clinically approved drugs modulate autophagy to varying extents, although they are not currently utilized for the therapeutic purpose of manipulating autophagy. In this review, we highlight the functional roles of autophagy in lung diseases with focus on the recent progress of the potential therapeutic use of autophagy-modifying drugs in clinical medicine. The purpose of this review is to discuss the merits, and the pitfalls, of modulating autophagy as a therapeutic strategy in lung diseases.
Novel Low Complexity Pulse-Triggered Flip-Flop for Wireless Baseband Applications
Authors: Chu Hung-Chi , Lin Jin-Fa , Hu Dong-Ting
Published: May 2013

A low complexity dual-mode pulse-triggered FF design for wireless baseband processing is presented in this paper. It supports both single-edge- and double-edge-triggered operations subject to a mode select control. Due to the novelty in pulse generator design, the layout area overhead is only 8% when compared with other single-mode counterpart design. Postlayout simulations in TSMC 1P6M 0.18 μm CMOS process model also indicate that the proposed design is as efficient as its single-mode counterpart in various performance metrics.
Several Dynamic Properties of Solutions to a Generalized Camassa-Holm Equation
Authors: Yin Zheng
Published: May 2013

For a nonlinear generalization of the Camassa-Holm equation, we investigate the dynamic properties of solutions for the equation under the assumption that the initial valueu0(x)lies in the spaceH1(R). A one-sided upper bound estimate on the first-order spatial derivative,Lpbound estimate, and a space-time higher-norm estimate for the solutions are obtained.
Investigation of the Effect of Occupational Noise Exposure on Blood Pressure and Heart Rate of Steel Industry Workers
Authors: Zamanian Zahra , Rostami Reza , Hasanzadeh Jafar , Hashemi Hassan
Published: May 2013

Background and Objectives. This study aimed to investigate the effect of noise exposure on blood pressure and heart rate of steel industry workers.Materials and Methods. In the present cross-sectional study, 50 workers were selected from a steel company in Fars province, Iran, and exposed to 85, 95, and 105 dB noise levels for 5 minutes. The participants' blood pressure and heart rate were measured using Beurer BC16 pulse meter both before and after the exposure.Results. The study results showed no significant difference in blood pressure and heart rate before and after the exposure. However, the workers' systolic blood pressure had increased compared to before the exposure; of course, the difference was not statistically significant (P>0.05). Besides, although the subjects' heart rate had reduced in comparison to before the exposure, the difference was not statistically significant (P>0.05).Conclusion. No significant change was observed in blood pressure and heart rate after acute exposure to 85, 95, and 105 dB noise levels.
Primo Vascular System in the Subarachnoid Space of a Mouse Brain
Authors: Moon Sang-Ho , Cha Richard , Lee Geo-Lyong , Lim Jae-Kwan , Soh Kwang-Sup
Published: May 2013

Objective. Recently, a novel circulatory system, the primo vascular system (PVS), was found in the brain ventricles and in the central canal of the spinal cord of a rat. The aim of the current work is to detect the PVS along the transverse sinuses between the cerebrum and the cerebellum of a mouse brain.Materials and Methods. The PVS in the subarachnoid space was analyzed after staining with4',6-diamidino-2-phenylindole (DAPI) and phalloidin in order to identify the PVS. With confocal microscopy and polarization microscopy, the primo vessel underneath the sagittal sinus was examined. The primo nodes under the transversal sinuses were observed after peeling off the dura and pia maters of the brain.Results. The primo vessel underneath the superior sagittal sinus was observed and showed linear optical polarization, similarly to the rabbit and the rat cases. The primo nodes were observed under the left and the right transverse sinuses at distances of 3,763 μm and 5,967 μm. The average size was 155 μm × 248 μm.Conclusion. The observation of primo vessels was consistent with previous observations in rabbits and rats, and primo nodes under the transverse sinuses were observed for the first time in this work.
Electrogastrography in Adults and Children: The Strength, Pitfalls, and Clinical Significance of the Cutaneous Recording of the Gastric Electrical Activity
Authors: Riezzo Giuseppe , Russo Francesco , Indrio Flavia
Published: May 2013

Cutaneous electrogastrography (EGG) is a non-invasive technique to record gastric myoelectrical activity from the abdominal surface. Although the recent rapid increase in the development of electrocardiography, EGG still suffers from several limitations. Currently, computer analysis of EGG provides few reliable parameters, such as frequency and the percentage of normal and altered slow wave activity (bradygastria and tachygastria). New EGG hardware and software, along with an appropriate arrangement of abdominal electrodes, could detect the coupling of the gastric slow wave from the EGG. At present, EGG does not diagnose a specific disease, but it puts in evidence stomach motor dysfunctions in different pathological conditions as gastroparesis and functional dyspepsia. Despite the current pitfalls of EGG, a multitasking diagnostic protocol could involve the EGG and the13C-breath testing for the evaluation of the gastric emptying time—along with validated gastrointestinal questionnaires and biochemical evaluations of the main gastrointestinal peptides—to identify dyspeptic subgroups. The present review tries to report the state of the art about the pathophysiological background of the gastric electrical activity, the recording and processing methodology of the EGG with particular attention to multichannel recording, and the possible clinical application of the EGG in adult and children.
A Concept Analysis of Attitude toward Getting Vaccinated against Human Papillomavirus
Authors: Ratanasiripong Nop T. , Chai Kathleen T.
Published: May 2013

In the research literature, the concept of attitude has been used and presented widely. However, attitude has been inconsistently defined and measured in various terms. This paper presents a concept analysis, using the Wilsonian methods modified by Walker and Avant (2004), to define and clarify the concept of attitude in order to provide an operationalized definition for a research study on attitudes toward a behavior: getting vaccinated against HPV. While the finding is not conclusive, three attributes of attitude: belief, affection, and evaluation are described. A theoretical definition and sample cases are constructed to illustrate the concept further. Antecedents, consequences, and empirical referents are discussed. Recommendations regarding the use of the concept of attitude in research, nursing practice, and nursing education are also made.
Electroacupuncture Inhibition of Hyperalgesia in Rats with Adjuvant Arthritis: Involvement of Cannabinoid Receptor 1 and Dopamine Receptor Subtypes in Striatum
Authors: Shou Yin , Yang Yang , Xu Ming-Shu , Zhao Ying-Qian , Ge Lin-Bao , Zhang Bi-Meng
Published: May 2013

Electroacupuncture (EA) has been regarded as an alternative treatment for inflammatory pain for several decades. However, the molecular mechanisms underlying the antinociceptive effect of EA have not been thoroughly clarified. Previous studies have shown that cannabinoid CB1 receptors are related to pain relief. Accumulating evidence has shown that the CB1 and dopamine systems sometimes interact and may operate synergistically in rat striatum. To our knowledge, dopamine D1/D2 receptors are involved in EA analgesia. In this study, we found that repeated EA at Zusanli (ST36) and Kunlun (BL60) acupoints resulted in marked improvements in thermal hyperalgesia. Both western blot assays and FQ-PCR analysis results showed that the levels of CB1 expression in the repeated-EA group were much higher than those in any other group (P=0.001). The CB1-selective antagonist AM251 inhibited the effects of repeated EA by attenuating the increases in CB1 expression. The two kinds of dopamine receptors imparted different actions on the EA-induced CB1 upregulation in AA rat model. These results suggested that the strong activation of the CB1 receptor after repeated EA resulted in the concomitant phenomenon of the upregulation of D1 and D2 levels of gene expression.
Polydextrose Enhances Calcium Absorption and Bone Retention in Ovariectomized Rats
Authors: Weisstaub Adriana R. , Abdala Victoria , Gonzales Chaves Macarena , Mandalunis Patricia , Zuleta Ángela , Zeni Susana
Published: May 2013

Purpose.To evaluate the effect of polydextrose (PDX) on Ca bioavailability and prevention of loss of bone mass.Methods.Twenty-four two-month-old ovariectomized rats were fed three isocaloric diets only varied in fiber source and content up to 60 days (FOS group, a commercial mixture of short- and long-chain fructooligosaccharide, OVX group fed AIN 93 diet, and PDX group). A SHAM group was included as control. Apparent Ca absorption percentage (%ABS), changes in total skeleton bone mineral content (tsBMC) and bone mineral density (BMD) and femur BMD, % Bone Volume, Ca and organic femur content, caecal weight, and pH were evaluated.Results.%ABS and caecum weight of PDX and FOS were higher, and caecum pH was lower compared to OVX and SHAM. PDX reached a higher pH and lower caecum weight than FOS possibly because PDX is not completely fermented in the colon. Changes in tsBMC and femur BMD in FOS and PDX were significant lower than SHAM but significantly higher than OVX. % Bone Volume and femur % of Ca in PDX were significantly higher than OVX and FOS but lower than SHAM.Conclusions. PDX increased Ca absorption and prevented bone loss in OVX rats.
PI3K/Akt Pathway Contributes to Neurovascular Unit Protection ofXiao-Xu-MingDecoction against Focal Cerebral Ischemia and Reperfusion Injury in Rats
Authors: Lan Rui , Xiang Jun , Zhang Yong , Wang Guo-Hua , Bao Jie , Li Wen-Wei , Zhang Wen , Xu Li-Li , Cai Ding-Fang
Published: May 2013

In the present study, we used a focal cerebral ischemia and reperfusion rat model to investigate the protective effects ofXiao-Xu-Mingdecoction (XXMD) on neurovascular unit and to examine the role of PI3K (phosphatidylinositol 3-kinase)/Akt pathway in this protection. The cerebral ischemia was induced by 90 min of middle cerebral artery occlusion. Cerebral infarct area was measured by tetrazolium staining, and neurological function was observed at 24 h after reperfusion. DNA fragmentation assay, combined with immunofluorescence, was performed to evaluate apoptosis of neuron, astrocyte, and vascular endothelial cell which constitute neurovascular unit. The expression levels of proteins involved in PI3K/Akt pathway were detected by Western blot. The results showed that XXMD improved neurological function, decreased cerebral infarct area and neuronal damage, and attenuated cellular apoptosis in neurovascular unit, while these effects were abolished by inhibition of PI3K/Akt with LY294002. We also found that XXMD upregulated p-PDKl, p-Akt, and p-GSK3βexpression levels, which were partly reversed by LY294002. In addition, the increases of p-PTEN and p-c-Raf expression levels on which LY294002 had no effect were also observed in response to XXMD treatment. The data indicated the protective effects of XXMD on neurovascular unit partly through the activation of PI3K/Akt pathway.
Properties of Expected Residual Minimization Model for a Class of Stochastic Complementarity Problems
Authors: Luo Mei-Ju , Lu Yuan
Published: May 2013

Expected residual minimization (ERM) model which minimizes an expected residual function defined by an NCP function has been studied in the literature for solving stochastic complementarity problems. In this paper, we first give the definitions of stochasticP-function, stochasticP0-function, and stochastic uniformlyP-function. Furthermore, the conditions such that the function is a stochasticPP0-function are considered. We then study the boundedness of solution set and global error bounds of the expected residual functions defined by the “Fischer-Burmeister” (FB) function and “min” function. The conclusion indicates that solutions of the ERM model are robust in the sense that they may have a minimum sensitivity with respect to random parameter variations in stochastic complementarity problems. On the other hand, we employ quasi-Monte Carlo methods and derivative-free methods to solve ERM model.
Development and Validation of a Stability Indicating RP-HPLC Method for the Determination of Two Sun Protection Factors (Koptrizon and Tinosorb S) in Topical Pharmaceutical Formulations Using Experimental Designs
Authors: Roy Chinmoy , Chakrabarty Jitamanyu
Published: May 2013

A novel, simple, validated stability indicating HPLC method was developed for determination of Koptrizon and Tinosorb S. Stability indicating power of the method was established by forced degradation study. The chromatographic separation was achieved with Waters X Bridge column, by using mobile phase consisting of a mixture of acetonitrile : tetrahydrofuran : water (38 : 38 : 24, v/v/v). The method fulfilled validation criteria and was shown to be sensitive, with limits of detection (LOD) and quantitation (LOQ) of 0.024 and 0.08 μg  for Koptrizon and 0.048 and 0.16 μg  for Tinosorb S, respectively. The developed method is validated for parameters like precision, accuracy, linearity, solution stability, specificity, and ruggedness as per ICH norms. Design expert with ANOVA software with linear model was applied and a 23 full factorial design was employed to estimate the model coefficients and also to check the robustness of the method. Results of the two-level full factorial design, 23 with 10 runs including two-centre-point analysis based on the variance analysis (ANOVA), demonstrated that all three factors, as well as the interactions between retention time of Koptrizon, Tinosorb S, and USP plate count for Koptrizon, are statistically significant.
The Effect of Heat Transfer on MHD Marangoni Boundary Layer Flow Past a Flat Plate in Nanofluid
Authors: Sastry D. R. V. S. R. K. , Murti A. S. N. , Kantha T. Poorna
Published: May 2013

The problem of heat transfer on the Marangoni convection boundary layer flow in an electrically conducting nanofluid is studied. Similarity transformations are used to transform the set of governing partial differential equations of the flow into a set of nonlinear ordinary differential equations. Numerical solutions of the similarity equations are then solved through the MATLAB “bvp4c” function. Different nanoparticles like Cu, Al2O3, and TiO2 are taken into consideration with water as base fluid. The velocity and temperature profiles are shown in graphs. Also the effects of the Prandtl number and solid volume fraction on heat transfer are discussed.
Involvement of Endoplasmic Reticulum Stress in Capsaicin-Induced Apoptosis of Human Pancreatic Cancer Cells
Authors: Lin Shengzhang , Zhang Jianhong , Chen Hui , Chen Kangjie , Lai Fuji , Luo Jiang , Wang Zhaohong , Bu Heqi , Zhang Riyuan , Li Honghai , Tong Hongfei
Published: May 2013

Capsaicin, main pungent ingredient of hot chilli peppers, has been shown to have anticarcinogenic effect on various cancer cells through multiple mechanisms. In this study, we investigated the apoptotic effect of capsaicin on human pancreatic cancer cells in bothin vitroandin vivosystems, as well as the possible mechanisms involved.In vitro, treatment of both the pancreatic cancer cells (PANC-1 and SW1990) with capsaicin resulted in cells growth inhibition, G0/G1 phase arrest, and apoptosis in a dose-dependent manner. Knockdown of growth arrest- and DNA damage-inducible gene 153 (GADD153), a marker of the endoplasmic-reticulum-stress- (ERS-) mediated apoptosis pathway, by specific siRNA attenuated capsaicin-induced apoptosis both in PANC-1 and SW1990 cells. Moreover,in vivostudies capsaicin effectively inhibited the growth and metabolism of pancreatic cancer and prolonged the survival time of pancreatic cancer xenograft tumor-induced mice. Furthermore, capsaicin increased the expression of some key ERS markers, including glucose-regulated protein 78 (GRP78), phosphoprotein kinase-like endoplasmic reticulum kinase (phosphoPERK), and phosphoeukaryotic initiation factor-2α(phospho-eIF2α), activating transcription factor 4 (ATF4) and GADD153 in tumor tissues. In conclusion, we for the first time provide important evidence to support the involvement of ERS in the induction of apoptosis in pancreatic cancer cells by capsaicin.
Fructose: A Key Factor in the Development of Metabolic Syndrome and Hypertension
Authors: Khitan Zeid , Kim Dong Hyun
Published: May 2013

Diabetes mellitus and the metabolic syndrome are becoming leading causes of death in the world. Identifying the etiology of diabetes is key to prevention. Despite the similarity in their structures, fructose and glucose are metabolized in different ways. Uric acid, a byproduct of uncontrolled fructose metabolism is known risk factor for hypertension. In the liver, fructose bypasses the two highly regulated steps in glycolysis, glucokinase and phosphofructokinase, both of which are inhibited by increasing concentrations of their byproducts. Fructose is metabolized by fructokinase (KHK). KHK has no negative feedback system, and ATP is used for phosphorylation. This results in intracellular phosphate depletion and the rapid generation of uric acid due to activation of AMP deaminase. Uric acid, a byproduct of this reaction, has been linked to endothelial dysfunction, insulin resistance, and hypertension. We present possible mechanisms by which fructose causes insulin resistance and suggest actions based on this association that have therapeutic implications.
R-MAC: Risk-Aware Dynamic MAC Protocol for Vehicular Cooperative Collision Avoidance System
Authors: Guo Weijie , Huang Liusheng , Chen Long , Xu Hongli , Miao Chenglin
Published: May 2013

The key for cooperative collision avoidance (CCA) systems is the real-time and reliable delivery of safety-related messages among vehicles, which include periodical beacons and risk-triggered warning messages. In this paper, we first design a risk-aware dynamic medium-access control (R-MAC) protocol tailored for vehicular CCA applications. In this protocol, each frame is divided into two parts: TDMA segment for transferring beacons and CSMA segment for delivering warning messages. Then, we propose a stochastic model to predict the average total number of potential collisions in a platoon of vehicles, which determines the size of CSMA segment in the R-MAC protocol meticulously. Monte Carlo simulations validate that our model is reliable and practical. The performance of the R-MAC protocol is verified through theoretical analysis and extensive simulations under different traffic scenes. Simulation results show that R-MAC outperforms the traditional IEEE 802.11p protocol in terms of packets delivery rate and transmission delay, as well as the Jain's fairness index of the medium access between beacons and warning messages.
Excitation Kinetics of Impurity Doped Quantum Dot Triggered by Gaussian White Noise
Authors: Pal Suvajit , Sinha Sudarson Sekhar , Ganguly Jayanta , Ghosh Manas
Published: May 2013

We investigate the excitation kinetics of a repulsive impurity doped quantum dot initiated by the application of Gaussian white noise. In view of a comprehensive research we have considered both additive and multiplicative noise (in Stratonovich sense). The noise strength and the dopant location have been found to fabricate the said kinetics in a delicate way. Moreover, the influences of additive and multiplicative nature of the noise on the excitation kinetics have been observed to be prominently different. The investigation reveals emergence of maximization and saturation in the excitation kinetics as a result of complex interplay between various parameters that affect the kinetics. The present investigation is believed to provide some useful perceptions of the functioning of mesoscopic systems where noise plays some profound role.
Lymphangioma-Like Kaposi’s Sarcoma Presenting as Gangrene
Authors: Friedman Eitan R. , Farquharson Lesley , Warsch Jessica , Huo Ran , Milikowski Clara , Llinas Margarita
Published: May 2013

Kaposi’s sarcoma (KS) is a multicentric vascular neoplasm associated with the Kaposi’s sarcoma-associated herpes virus (KSHV). KS can occur in immunocompromised patients as well as certain populations in Africa or in the Mediterranean. Less than 5% of KS cases can present with lymphangioma-like kaposi sarcoma (LLKS), which can occur in all KS variants. KS presents with characteristic skin lesions that appear as brown, red, blue, or purple plaques and nodules. The lesions are initially flat and if untreated will become raised. LLKS presents similarly to KS but is associated with severe lymphedema and soft tissue swelling as well as bulla-like vascular lesions. We present the case of an 85-year-old Lebanese, HIV negative, man who presented with a swollen and painful right lower extremity accompanied by necrotic lesions. Wound cultures were positive, and we began the work-up for secondarily infected gangrene. However, skin biopsy results revealed that he in fact had lymphangioma-like Kaposi sarcoma, which allowed us to shift our management. Advanced Kaposi’s sarcoma can present similar to gangrene. It is important to recognize the typical skin lesions of KS and not to overlook Kaposi’s sarcoma or LLKS within the differential.
TET2 Mutations in Ph-Negative Myeloproliferative Neoplasms: Identification of Three Novel Mutations and Relationship with Clinical and Laboratory Findings
Authors: Patriarca Andrea , Colaizzo Donatella , Tiscia Gianluca , Spadano Raffaele , Di Zacomo Silvia , Spadano Antonio , Villanova Ida , Margaglione Maurizio , Grandone Elvira , Dragani Alfredo
Published: May 2013

High-throughput DNA sequence analysis was used to screen for TET2 mutations in peripheral blood derived DNA from 97 patients with BCR-ABL-negative myeloproliferative neoplasms (MPNs). Overall six mutations in the coding region of the gene were identified in 7 patients with an overall mutational frequency of 7.2%. In polycythemia vera patients (n=25) 2 mutations were identified (8%), and in those with essential thrombocythemia (n=55) 2 mutations (3.6%); in those with unclassifiable MPN (n=8) 3 mutations (37.5%). No primary myelofibrosis patients (n=6) harboured TET2 mutations. Three unreported mutations were identified (p.P177fs, p.C1298del, and p.P411del), the first two in patients with unclassifiable MPN, the last in a patient with essential thrombocythemia. On multivariate analysis the diagnosis of an unclassifiable MPN was significantly related to the presence of TET2 mutations (P=0.02; OR: 2.81; 95% CI 1.11–7.06). We conclude that TET2 mutations occur in both JAK2 V617F-positive and -negative MPNs and are more frequent in MPN-U patients. This could represent the biological link between the different classes of myeloid malignancies.
Charge Transfer in Nanocrystalline Semiconductor Electrodes
Authors: Bouroushian M.
Published: May 2013

Nanocrystalline electrodes in liquid junction devices possess a number of unique properties arising from their convoluted structure and the dimensions of their building units. The light-induced charge separation and transport in photoelectrochemical systems using nanocrystalline/nanoporous semiconductor electrodes is discussed here in connection with the basic principles of the (Schottky) barrier theory. Recent models for charge transfer kinetics in normal and unipolar (dye-sensitized) cells are reviewed, and novel concepts and materials are considered.
Invasive Measures of Afterload in Low Gradient Severe Aortic Stenosis With Preserved Ejection Fraction
Authors: Eleid Mackram F. , Nishimura Rick A. , Borlaug Barry A. , Sorajja Paul
Published: May 2013

Background—

The pathophysiology of low flow, low gradient severe aortic stenosis (LGSAS) with preserved ejection fraction is poorly understood. It has been proposed that abnormalities of arterial circulation are a major contributor to this syndrome.

Methods and Results—

We invasively examined systemic arterial afterload (effective arterial elastance, Ea; total arterial compliance, Ca; and systemic vascular resistance index) in patients with LGSAS (mean gradient, <40 mm Hg; aortic valve area, <1.0 cm
2
) and preserved ejection fraction (≥50%), and compared these findings with patients with high gradient (≥40 mm Hg) severe aortic stenosis (HGSAS) and moderate AS (mean gradient, <40 mm Hg; aortic valve area, >1.0 cm
2
). Patients with LGSAS (n=36), HGSAS (n=31), and moderate AS (n=19) were similar with respect to age, sex, body size, symptoms, comorbidities, and ejection fraction. Aortic valve area was similar between groups with LGSAS and HGSAS, but the patients with LGSAS had reduced stroke volume index and cardiac index (
P
=0.003 for both). In comparison with patients with HGSAS and moderate AS, measures of afterload, including Ea (4.02±0.98 versus 3.13±0.81 and 3.06±0.79 mm Hg·m
2
/mL;
P
<0.0001) and systemic vascular resistance index (3116±799 versus 2515±645 and 2380±546 dyn·s·m
2
/cm
5
;
P
=0.001), were significantly higher in LGSAS, whereas Ca was lower (0.46±0.16 versus 0.57±0.13 and 0.59±0.19 mL/m
2
per mm Hg;
P
=0.002). All invasive measures of arterial afterload were related to stroke volume index.

Conclusions—

Patients with LGSAS and preserved ejection fraction display elevated arterial afterload compared with patients with HGSAS and moderate AS. These findings identify systemic arterial effects that contribute to the hemodynamic presentation in patients with LGSAS and help to further define this entity.
Coronary Collaterals Predict Improved Survival and Allograft Function in Patients With Coronary Allograft Vasculopathy
Authors: Lavine Kory J. , Sintek Marc , Novak Eric , Ewald Gregory , Geltman Edward , Joseph Susan , Pfeifer John , Mann Douglas L.
Published: May 2013

Background—

Despite improvements in the care of patients who have received cardiac transplants, coronary allograft vasculopathy (CAV) remains the most prevalent cause of late allograft failure and cardiac mortality. Few proven therapies are available for this important disease. The presence of coronary collaterals imparts a favorable prognosis in patients with native ischemic heart disease; however, the impact of collaterals in CAV is unknown.

Methods and Results—

To determine whether the development of coronary collaterals is associated with improved outcomes in patients with CAV, we performed a retrospective analysis of patients followed in the heart transplant program at Barnes Jewish Hospital from 1994 to 2008. The primary end points included all cause mortality and the composite of all cause mortality, retransplantation, and inotrope dependence. We screened 485 patients and identified 59 (12%) subjects with moderate-to-severe CAV. Angiographically visible coronary collaterals were present in 34 (57%) subjects. Kaplan–Meier and Cox multivariable analyses revealed that patients with collaterals had reduced incidence of all cause mortality (hazard ratio, 0.20;
P
<0.001) and the composite end point (hazard ratio, 0.17;
P
<0.001). In addition, patients with collaterals had less severe heart failure symptoms as measured by New York Heart Association class. Immunostaining of biopsy specimens revealed that among patients with CAV, the presence of coronary collaterals correlated with increased microvascular density, reduced fibrosis, and decreased left ventricular end-diastolic pressure.

Conclusions—

Together, these data demonstrate that the presence of coronary collaterals predicts a favorable prognosis in patients with CAV and suggests that interventions aimed at promoting collateral and microvascular growth may serve as effective therapies for this disease.
Shortening of the Elastic Tandem Immunoglobulin Segment of Titin Leads to Diastolic Dysfunction
Authors: Chung Charles S. , Hutchinson Kirk R. , Methawasin Mei , Saripalli Chandra , Smith John E. , Hidalgo Carlos G. , Luo Xiuju , Labeit Siegfried , Guo Caiying , Granzier Henk L.
Published: May 2013

Background—

Diastolic dysfunction is a poorly understood but clinically pervasive syndrome that is characterized by increased diastolic stiffness. Titin is the main determinant of cellular passive stiffness. However, the physiological role that the tandem immunoglobulin (Ig) segment of titin plays in stiffness generation and whether shortening this segment is sufficient to cause diastolic dysfunction need to be established.

Methods and Results—

We generated a mouse model in which 9 Ig-like domains (Ig3–Ig11) were deleted from the proximal tandem Ig segment of the spring region of titin (IG KO). Exon microarray analysis revealed no adaptations in titin splicing, whereas novel phospho-specific antibodies did not detect changes in titin phosphorylation. Passive myocyte stiffness was increased in the IG KO, and immunoelectron microscopy revealed increased extension of the remaining titin spring segments as the sole likely underlying mechanism. Diastolic stiffness was increased at the tissue and organ levels, with no consistent changes in extracellular matrix composition or extracellular matrix–based passive stiffness, supporting a titin-based mechanism for in vivo diastolic dysfunction. Additionally, IG KO mice have a reduced exercise tolerance, a phenotype often associated with diastolic dysfunction.

Conclusions—

Increased titin-based passive stiffness is sufficient to cause diastolic dysfunction with exercise intolerance.
A revision of Lophopappus (Asteraceae, Nassauvieae)
Authors: KATINAS LILIANA , SANCHO GISELA , VITALI MAIRA S.
Published: May 2013

Lophopappus (Asteraceae, Nassauvieae) comprises five species endemic to South America. The genus is defined by its shrubby habit with unarmed branches, actinodromous or acrodromous leaf venation, solitary or few capitula at the apex of the branches with bilabiate and/or tubular-funnelform corollas, dorsally papillose style branches, and apically plumose pappus bristles. Leaf anatomy, cypsela trichomes, and pappus morphology are examined here for the first time in this genus. Lophopappus cuneatus is corroborated as a distinct species, L. berberidifolius is established as a synonym of L. tarapacanus, and a lectotype is designated for L. foliosus. A comprehensive key to the species and detailed descriptions, geographical distribution, phenology, illustrations and distribution maps are provided for all taxa.
Simulating the Impact of Climate Change on Runoff in a Typical River Catchment of the Loess Plateau, China
Authors: Wang G. Q. , Zhang J. Y. , Xuan Y. Q. , Liu J. F. , Jin J. L. , Bao Z. X. , He R. M. , Liu C. S. , Liu Y. L. , Yan X. L.
Published: May 2013

Global warming will have direct impacts on regional water resources by accelerating the hydrological cycle. Hydrological simulation is an important approach to studying climate change impacts. In this paper, a snowmelt-based water balance model (SWBM) was used to simulate the effect of climate change on runoff in the Kuye River catchment of the Loess Plateau, China. Results indicated that the SWBM is suitable for simulating monthly discharge into arid catchments. The response of runoff in the Kuye River catchment to climate change is nonlinear, and runoff is more sensitive to changes in precipitation than to changes in temperature. The projections indicated that the Kuye River catchment would undergo more flooding in the 2020s, and global warming would probably shorten the main flood season in the catchment, with greater discharge occurring in August. Although projected changes in annual runoff are uncertain, the possibilities of regional water shortages and regional flooding are essential issues that need to be fully considered.
Composite materials dynamic back face deflection characteristics during ballistic impact
Authors: Freitas Christopher J , Bigger Rory P , Scott Nikki , LaSala Victor , MacKiewicz James
Published: May 2013

The current rationale for development of composite combat helmets is to either maintain performance at reduced weight or maintain weight with a significantly higher level of ballistic performance. Typically, weight reduction with maintained performance is the design approach used. In order to reduce weight with the same materials requires a reduction of material thickness. Thinner structural materials then introduce the complicating and often limiting factor of greater back face deflection. To further understand the tradeoffs of ballistic performance and efficiency, weight and back face deflection, a research project was undertaken. In this research project, a set of 17 composite materials were investigated. The digital image correlation method was used to directly measure the characteristics of the dynamic back face deflection of targets engaged by a set of threats. The analysis of this data, which includes dynamic deflection time histories, back face velocity time histories, strain time histories and spatial distributions of these quantities, allowed for assessment of candidate material performance and characterization of back face deflection. The details of this experimental program and key data results are presented in this paper.
How Firms Capture Value From Their Innovations
Authors: James Sharon D. , Leiblein Michael J. , Lu Shaohua
Published: May 2013

Over the past 25 years, the technology strategy literature has examined how four primary mechanisms—patents, secrecy, lead time, and complementary assets—influence whether and to what extent firms capture value generated by their innovations. Although this literature has had a profound impact on our understanding of how firms capture value from innovation, we have yet to develop a robust theory that allows us to unbundle the characteristics of institutions, industries, firms, and individual technologies that affect the selection of particular value capture mechanisms. The purpose of this article is to provide a foundation for addressing these gaps in the literature. We identify and assess relevant scholarly work regarding value capture mechanisms published in top-tier peer-reviewed management journals between 1980 and 2011. We then review the assumptions, insights, and causal mechanisms for the antecedents and consequences of the value capture mechanisms highlighted in these articles. The ultimate objective is to identify research opportunities that help to better understand the conditions under which specific bundles of value capture mechanisms are most likely to help innovating firms achieve persistent superior performance.
The Art in Knowing a Landscape
Authors: Berleant Arnold
Published: May 2013

The arts can contribute to an intimate, engaged experience of landscape, and this process can itself be construed as an art. Experiencing landscape through the arts and as an art, the art of environmen-tal appreciation, offers a clearer understanding of landscape, of environment, and of art, as well as what it is to “know” in the context of environmental experience. This essay offers a new fabric for understanding the relation of art and landscape by combining a fresh understanding of four threads: art, environment, landscape, and knowing through appreciation. It shows how the loose-knit texture they form can be spread metaphorically over a particular landscape in such a way that the landscape will fill the fabric and the fabric integrate the landscape.
Large eddy simulation of the flow around a train passing a stationary freight wagon
Authors: Liu Yebo , Hemida Hassan , Liu Zhiming
Published: May 2013

In this paper, the effect of track spacing on the aerodynamic performance of a stationary double-stacked freight wagon passed by a high-speed passenger train is investigated using large eddy simulation (LES). The passenger train is a 1/20th scale model of an ICE2-shaped high-speed train and consists of nose, two coaches, inter-carriage gap and tail. Based on the speed and height of the passenger train, a flow Reynolds number of 2 × 105 is used in the simulation studies. To isolate the effect of the mesh resolution computations are performed using three different meshes: coarse, medium and fine, consisting of 3.2 × 106, 6.9 × 106 and 9.0 × 106 nodes, respectively. The results are also validated with available experimental data and a good agreement is demonstrated. The aerodynamic loads on the freight containers and passenger train are obtained during a passing process. High side force values are generated on the freight containers when the passenger train approaches followed by a sudden reduction when the nose of the passenger train passes the freight wagons. There is also a reduction in the side force when the tail of the passenger train passes the freight wagon followed by a significant increase when the wake flow hits the freight wagon. Similar behavior is observed for the lift and drag coefficients. The effect of track spacing is investigated by performing simulations at three different track spacing values: 3.5, 4 and 4.5 m. The results show that a reduction in track spacing generally increases the aerodynamic forces on both the freight wagon and passenger train.
Knowing Women
Authors: Buss Doris E
Published: May 2013

This article considers how international criminal courts produce knowledge about women’s experiences of large-scale violence. In 2001, the International Criminal Tribunal for Yugoslavia concluded that the crime of genocide had been committed in Srebrenica in 1995 and that the patriarchal nature of the Bosnian Muslim community was key to the genocide. This paper examines the processes by which the trial and appeal chambers came to know, and author an account of this community as patriarchal. I examine the transcripts of three witnesses who testified about the surviving community of Bosnian Muslim women, tracing how evidence was shaped and reshaped in the courtroom and then in the trial and appeal judgments. I argue here for the importance of exploring the mediating practices and actors that produce legal knowledge, to better understand how complex recognition of gendered harm unfolds, and is sometimes curtailed, through international criminal adjudication.
Planar grained structures with multiple inclusions in a periodic cell: Elastostatic solution and its potential applications
Authors: Vigdergauz Shmuel
Published: May 2013

The simple analytical expressions for the effective moduli and related quantities of interest in a planar doubly periodic matrix-inclusion structure previously obtained for only one inclusion in a cell are generalized on a finite number of non-intersecting inclusions each having its own local properties. As before, all phases are treated as linear and isotropic with perfectly bonding along smooth material interfaces. The derivations are performed by the complex variable technique applied to the quasi-periodic Weierstrassian zeta-function. Special attention is given to the equi-stress inclusion shapes (ESSs) where the analytical development can be fully completed. In particular, they are proved to saturate the multi-phase Hashin–Shtrikman bounds on the effective bulk modulus. The necessary condition of the ESSs existence is also found, although the question of whether they really exist is left aside. The results obtained form a basis for further numerical analysis of the attendant direct and optimization problems which are briefly discussed.
Business, Ecosystems, and Biodiversity
Authors: Winn Monika I. , Pogutz Stefano
Published: May 2013

Whether to secure critical resource inputs or responding to demands ranging from local communities to international stakeholders, leading multinational companies increasingly engage in ecosystem management by developing operations models with biodiversity, ecosystem conservation, and ecosystem restoration in mind—often in partnership with international conservation organizations. While promising to infuse business strategy with knowledge from natural science, specifically ecology, the emerging practice appears well ahead of research in this area. This article aims to encourage research into how organizations can manage their relationship with the natural environment so as not to destroy the very life-supporting foundations provided by nature. Bridging knowledge domains, the article introduces key concepts from ecology and social ecology to organization and management studies— ecosystems, biodiversity, ecosystem services, and ecological resilience. We illustrate these concepts with advances in ecosystems management and conclude with suggestions for future research in sustainability management, organization theory, and strategic management.