bluuebunny/crossref_metadata_2025 huggingface dataset:
Design Space Exploration for Quantifying a System Model’s Feasible Domain
Authors: Larson Brad J. , Mattson Christopher A.
Published: April 2012

A major challenge in multidisciplinary system design is predicting the effects of design decisions at the point these decisions are being made. Because decisions at the beginning of system design, when the least is known about the new system, have the greatest impact on its final behavior, designers are increasingly interested in using compositional system models (system models created from independent models of system components) to validate design decisions early in and throughout system design. Compositional system models, however, have several failure modes that often result in infeasible or failed model evaluation. In addition, these models change frequently as designs are refined, changing the model domain (set of valid inputs and states). To compute valid results, the system model inputs and states must remain within this domain throughout simulation. This paper develops an algorithm to efficiently quantify the system model domain. To do this, we (1) present a formulation for system model feasibility and identify types of system model failures, (2) develop a design space exploration algorithm that quantifies the system model domain, and (3) illustrate this algorithm using a solar-powered unmanned aerial vehicle model. This algorithm enables systematic improvements of compositional system model feasibility.
A New Closure Strategy for Proper Orthogonal Decomposition Reduced-Order Models
Authors: Akhtar Imran , Wang Zhu , Borggaard Jeff , Iliescu Traian
Published: April 2012

Proper orthogonal decomposition (POD) is one of the most significant reduced-order modeling (ROM) techniques in fluid mechanics. However, the application of POD based reduced-order models (POD-ROMs) is primarily limited to laminar flows due to the decay of physical accuracy. A few nonlinear closure models have been developed for improving the accuracy and stability of the POD-ROMs, which are generally computationally expensive. In this paper we propose a new closure strategy for POD-ROMs that is both accurate and effective. In the new closure model, the Frobenius norm of the Jacobian of the POD-ROM is introduced as the eddy viscosity coefficient. As a first step, the new method has been tested on a one-dimensional Burgers equation with a small dissipation coefficient ν=10-3. Numerical results show that the Jacobian based closure model greatly improves the physical accuracy of the POD-ROM, while maintaining a low computational cost.
Experimental Investigation of Irreversibility of a Proton Exchange Membrane Fuel Cell
Authors: Khazaee I.
Published: April 2012

For an 11 W proton exchange membrane (PEM) fuel cell, the exergy analysis at different channel geometry and internal parameters such as temperature, pressure, and mass flow rate are investigated experimentally. The geometry of the cell is rectangular, elliptical, and triangular. A PEM fuel cell with 25cm2 active area and Nafion 117 membrane with 4 mg Pt cm-2 for the anode and cathode is employed as a membrane electrode assembly. The results show that when the geometry of the cell is rectangular, the irreversibility of the cell is at lower value and the exergy efficiency is at higher value. Also, the results show that with the increase of hydrogen, oxygen, and cell temperature, the exergy efficiencies of the cell increase and irreversibilities decrease.
Disassembly and Reassembly Sequence Planning Tradeoffs Under Uncertainty for Product Maintenance
Authors: Behdad Sara , Thurston Deborah
Published: April 2012

The problem addressed in this paper is disassembly sequence planning for the purposes of maintenance or component upgrading, which is an integral part of the remanufacturing process. This involves disassembly, component repair or replacement, and reassembly. Each of these steps incurs cost as well as the probability of damage during the process. This paper presents a method for addressing these tradeoffs, as well as the uncertainty associated with them. A procedure for identifying the best sequence of disassembly operations for maintenance and/or component upgrade is presented. It considers both disassembly and reassembly costs and uncertainties. Graph-based integer linear programming combined with multi-attribute utility analysis is employed to identify the best set of tradeoffs among (a) disassembly time (and resulting cost) under uncertainty, (b) the probability of not incurring damage during disassembly, (c) reassembly time (and resulting cost), and (d) the probability of not incurring damage during reassembly. An example of a solar heating system is used to illustrate the method.
H5N1 influenza virus-like particles produced by transient expression in mammalian cells induce humoral and cellular immune responses in mice
Authors: Tao Ling , Chen Jianjun , Zheng Zhenhua , Meng Jin , Zhang Zhenfeng , Chen Yao , Luo Huanle , Li Hongxia , Chen Ze , Hu Qinxue , Wang Hanzhong
Published: April 2012

Vaccination is an effective way to protect from influenza virus infection. Among the new candidates of influenza vaccines, influenza virus-like particles (VLPs) seem to be promising. Here, we generated 2 types of H5N1 influenza VLPs by co-expressing influenza virus Env (envelope protein) and murine leukemia virus (MLV) Gag–Pol. VLPs generated by co-transfection of pHCMV-wtH5 or pHCMV-mtH5 with pSV-Mo-MLVgagpol and pHCMV-N1 were named as wtH5N1 VLPs or mtH5N1 VLPs. The plasmid of pHCMV-wtH5 encoded the wild-type hemagglutinin (HA) (wtH5) from A/swine/Anhui/ca/2004 (H5N1) with a multibasic cleavage site, while pHCMV-mtH5 encoded the modified mutant-type (mtH5) with a monobasic cleavage site. Influenza virus HA VLPs were characterized and equal amounts of them were used to immunize mice subcutaneously, intraperitoneally, or intramuscularly. The levels of HA-specific IgG1, IFN-γ, and neutralization antibodies were significantly induced in mice immunized with wtH5N1 VLPs or mtH5N1 VLPs via all 3 routes, while HA-specific IgG2a was barely detectable. IL-4 secretion was detected in mice subcutaneously immunized with wtH5N1 VLPs or mtH5N1 VLPs, or intramuscularly immunized with mtH5N1 VLPs. Our results indicated that both H5N1 influenza VLPs could induce specific humoral and cellular immune responses in immunized mice. In conclusion, our study provides helpful information for designing new candidate vaccines against H5N1 influenza viruses.
NEW SIMPLIFIED CORRELATIONS FOR AQUA-AMMONIA INTERMITTENT SOLAR-POWERED ABSORPTION REFRIGERATION SYSTEMS
Authors: EL-SHAARAWI M. A. I. , SAID S. A. M. , SIDDIQUI M. U.
Published: April 2012

Designing of an intermittently operating solar powered aqua-ammonia absorption system requires determination of design parameters such as operating pressures, operating aqua-ammonia concentrations, energy requirement of all components of the system, etc. These design parameters are mainly dependent on four operating temperatures, namely, the condenser/day-ambient, the absorber/night-ambient, the evaporator/cooling-load, and the generator temperatures. The present study presents a set of new polynomial form of correlations for directly estimating these design parameters as a function of the four operating temperatures. The developed correlations are simple, easy to use and estimate the design parameters for both, constant pressure and constant temperature absorption intermittent systems with a percentage error of less than 3%.
Photophysics of Fluorescent Probes for Single-Molecule Biophysics and Super-Resolution Imaging
Authors: Ha Taekjip , Tinnefeld Philip
Published: April 2012

Single-molecule fluorescence spectroscopy and super-resolution microscopy are important elements of the ongoing technical revolution to reveal biochemical and cellular processes in unprecedented clarity and precision. Demands placed on the photophysical properties of the fluorophores are stringent and drive the choice of appropriate probes. Such fluorophores are not simple light bulbs of a certain color and brightness but instead have their own “personalities” regarding spectroscopic parameters, redox properties, size, water solubility, photostability, and several other factors. Here, we review the photophysics of fluorescent probes, both organic fluorophores and fluorescent proteins, used in applications such as particle tracking, single-molecule FRET, stoichiometry determination, and super-resolution imaging. Of particular interest is the thiol-induced blinking of Cy5, a curse for single-molecule biophysical studies that was later overcome using Trolox through a reducing/oxidizing system but a boon for super-resolution imaging owing to the controllable photoswitching. Understanding photophysics is critical in the design and interpretation of single-molecule experiments.
Neurotrophin Signaling via Long-Distance Axonal Transport
Authors: Chowdary Praveen D. , Che Dung L. , Cui Bianxiao
Published: April 2012

Neurotrophins are a family of target-derived growth factors that support survival, development, and maintenance of innervating neurons. Owing to the unique architecture of neurons, neurotrophins that act locally on the axonal terminals must convey their signals across the entire axon for subsequent regulation of gene transcription in the cell nucleus. This long-distance retrograde signaling, a motor-driven process that can take hours or days, has been a subject of intense interest. In the last decade, live-cell imaging with high sensitivity has significantly increased our capability to track the transport of neurotrophins, their receptors, and subsequent signals in real time. This review summarizes recent research progress in understanding neurotrophin-receptor interactions at the axonal terminal and their transport dynamics along the axon. We emphasize high-resolution studies at the single-molecule level and also discuss recent technical advances in the field.
Singlet Nuclear Magnetic Resonance
Authors: Levitt Malcolm H.
Published: April 2012

Nuclear singlet states may have lifetimes that are much longer than the conventional relaxation time of nuclear spin magnetization. This review covers how these states may be generated, observed, and exploited in solution nuclear magnetic resonance (NMR). Potential applications include the study of slow molecular processes, the elucidation of molecular geometry, and the transport of hyperpolarized nuclear spin order.
Photochemical and Photoelectrochemical Reduction of CO2
Authors: Kumar Bhupendra , Llorente Mark , Froehlich Jesse , Dang Tram , Sathrum Aaron , Kubiak Clifford P.
Published: April 2012

The recent literature on photochemical and photoelectrochemical reductions of CO2 is reviewed. The different methods of achieving light absorption, electron-hole separation, and electrochemical reduction of CO2 are considered. Energy gap matching for reduction of CO2 to different products, including CO, formic acid, and methanol, is used to identify the most promising systems. Different approaches to lowering overpotentials and achieving high chemical selectivities by employing catalysts are described and compared.
Environmental Chemistry at Vapor/Water Interfaces: Insights from Vibrational Sum Frequency Generation Spectroscopy
Authors: Jubb Aaron M. , Hua Wei , Allen Heather C.
Published: April 2012

The chemistry that occurs at surfaces has been an intense area of study for many years owing to its complexity and importance in describing a wide range of physical phenomena. The vapor/water interface is particularly interesting from an environmental chemistry perspective as this surface plays host to a wide range of chemistries that influence atmospheric and geochemical interactions. The application of vibrational sum frequency generation (VSFG), an inherently surface-specific, even-order nonlinear optical spectroscopy, enables the direct interrogation of various vapor/aqueous interfaces to elucidate the behavior and reaction of chemical species within the surface regime. In this review we discuss the application of VSFG to the study of a variety of atmospherically important systems at the vapor/aqueous interface. Chemical systems presented include inorganic ionic solutions prevalent in aqueous marine aerosols, small molecular solutes, and long-chain fatty acids relevant to fat-coated aerosols. The ability of VSFG to probe both the organization and reactions that may occur for these systems is highlighted. A future perspective toward the application of VSFG to the study of environmental interfaces is also provided.
Computational Studies of Pressure, Temperature, and Surface Effects on the Structure and Thermodynamics of Confined Water
Authors: Giovambattista N. , Rossky P.J. , Debenedetti P.G.
Published: April 2012

The behavior of water confined on nanometer length scales is important in a diverse set of technical and scientific contexts, ranging from the performance of fuel cells and biological molecular machines to the design of self-assembling nanoscale materials. Here, we review recent insights into the structure and thermodynamics of confined water that have been elucidated primarily by computer simulation studies. We emphasize investigations in which interfacial chemistry and molecular topography are varied systematically and in which a wide range of thermodynamic conditions of temperature and pressure are explored. We consider homogeneous interfaces ranging from the simplest hard wall to chemically realistic, but structurally ideal, hydrophobic and hydrophilic surfaces, and the continuous scale of surface polarity is investigated. Features associated with interface heterogeneities arising from chemical patterning or from the natural characteristics of protein surfaces are discussed. Finally, we provide our thoughts on important directions for further studies.
Normal human melanocytes exposed to chronic insulin and glucose supplementation undergo oncogenic changes and methyl group metabolism cellular redistribution
Authors: Morvan Daniel , Steyaert Jean Marc , Schwartz Laurent , Israel Maurice , Demidem Aicha
Published: April 2012

Recent epidemiological studies have suggested a link between cancer and pathophysiological conditions associated with hyperinsulinemia. In this report, we address the possible role of insulin exposure in melanocyte transformation. To this aim, normal melanocytes were exposed to chronic insulin and glucose supplementation (twice the standard medium concentration) for at least 3 wk. After 3-wk treatment, melanocytes increased proliferation (doubling time: 2.7 vs. 5.6 days, P < 0.01). After 3-wk treatment or after 3-wk treatment followed by 4-wk reculture in standard medium, melanocytes were able to grow in soft agar colonies. Treated melanocytes had increased DNA content (+8%, P < 0.05), chromosomal aberrations, and modified oncoprotein profile: p-Akt expression increased (+32%, P < 0.01), Akt decreased, and c-Myc increased (+40%, P < 0.05). PP2A protein expression increased (+42, P < 0.05), while PP2A methylation decreased (−42%, P < 0.05), and PP2A activity was reduced (−27%, P < 0.05). PP2A transcription level was increased ( ppp2r1a, PP2A subunit A, +44%, P < 0.05). Also, transcriptomic data revealed modifications in insr (insulin receptors, +10%, P < 0.05) and Il8 (inflammation protein, +99%, P < 0.01). Glycolysis was modified with increased transcription of Pgk1 and Hif1a ( P < 0.05), decreased transcription of Pfkfb3 ( P < 0.05), decreased activity of pyruvate kinase ( P < 0.01), and decreased pyruvate cell content as assessed by 1H-NMR spectroscopy. In addition, methyl group metabolism was altered with decreased global DNA methylation (−51%, P < 0.01), increased cytosolic protein methylation (+18%, P < 0.05), and consistent changes in methylated species on 1H-NMR spectra. In conclusion, exposure to chronic insulin and glucose supplementation induces oncogenic changes and methyl group metabolism redistribution, which may be a biomarker of transformation.
Inadvertent Subclavian Artery Cannulation: Endovascular Repair Using a Collagen Closure Device—Report of Two Cases and Review of the Literature
Authors: Ananthakrishnan Ganapathy , White Richard D. , Bhat Rajesh , Chakraverty Sam
Published: April 2012

Inadvertent line insertion into the subclavian artery is an uncommon complication of subclavian venous catheterisation, and its timely recognition is vital to minimise risk of harm to the patient. We describe the radiographic, computed tomographic (CT), and angiographic findings in two patients and illustrate the subsequent endovascular management using collagen vascular closure devices.
Evaluation of Serum Adipokines in Peripheral Arterial Occlusive Disease
Authors: Gherman Claudia D. , Mironiuc Aurel I.
Published: April 2012

Aim. Out study aimed to assess the serum levels of adipokines in patients with peripheral arterial occlusive disease (PAOD) caused by atherosclerosis.Methods. Serum samples were obtained from 221 patients. One hundred and forty patients, (26 females and 114 males) met the inclusion criteria and were assigned into the case group. Eighty one patients (17 females and 64 males), were included in the control group. Circulating plasma levels of adiponectin, leptin, resistin, and TNF-αwere measured using the enzyme-linked immunosorbent assay (ELISA) method.Results. Significant lower levels of adiponectin were present () in PAOD patients ( pg/mL) compared to the control group ( pg/mL). The mean value of leptin ( pg/mL) and resistin (2047.81±3301.08 pg/mL) patients included in the PAOD group was higher, as compared to the control group. Statistically significant difference was found between the two groups for leptin () and for resistin (). No statistically significant difference for TNF-αwas found between the two groups ().Conclusion. The markers of inflammation secreted by the adipose tissue (adiponectin, leptin, resistin) showed significant differences in patients from the case group (with PAOD) compared to the control group.
Cognitive Functions and Cognitive Reserve in Relation to Blood Pressure Components in a Population-Based Cohort Aged 53 to 94 Years
Authors: Giordano Nunzia , Tikhonoff Valérie , Palatini Paolo , Bascelli Anna , Boschetti Giovanni , De Lazzari Fabia , Grasselli Carla , Martini Bortolo , Caffi Sandro , Piccoli Antonio , Mazza Alberto , Bisiacchi Patrizia , Casiglia Edoardo
Published: April 2012

In 288 men and women from general population in a cross-sectional survey, all neuropsychological tests were negatively associated with age; memory and executive function were also positively related with education. The hypertensives (HT) were less efficient than the normotensives (NT) in the test of memory with interference at 10 sec (MI-10) (−33%,P=0.03), clock drawing test (CLOX) (−28%,P<0.01), and mini-mental state examination (MMSE) (−6%,P=0.02). Lower MMSE, MI-10, and CLOX were predicted by higher systolic (odds ratio, OR, 0.97,P=0.02; OR 0.98,P<0.005; OR 0.95,P<0.001) and higher pulse blood pressure (BP) (OR 0.97,P=0.02; OR 0.97,P<0.01; and 0.95,P<0.0001). The cognitive reserve index (CRI) was 6% lower in the HT (P=0.03) and was predicted by higher pulse BP (OR 0.82,P<0.001). The BP vectors of lower MMSE, MI-10, and CLOX were directed towards higher values of systolic and diastolic BP, that of low CRI towards higher systolic and lower diastolic. The label of hypertension and higher values of systolic or pulse BP are associated to worse memory and executive functions. Higher diastolic BP, although insufficient to impair cognition, strengthens this association. CRI is predicted by higher systolic BP associated to lower diastolic BP.
Aboveground Forest Biomass Estimation with Landsat and LiDAR Data and Uncertainty Analysis of the Estimates
Authors: Lu Dengsheng , Chen Qi , Wang Guangxing , Moran Emilio , Batistella Mateus , Zhang Maozhen , Vaglio Laurin Gaia , Saah David
Published: April 2012

Landsat Thematic mapper (TM) image has long been the dominate data source, and recently LiDAR has offered an important new structural data stream for forest biomass estimations. On the other hand, forest biomass uncertainty analysis research has only recently obtained sufficient attention due to the difficulty in collecting reference data. This paper provides a brief overview of current forest biomass estimation methods using both TM and LiDAR data. A case study is then presented that demonstrates the forest biomass estimation methods and uncertainty analysis. Results indicate that Landsat TM data can provide adequate biomass estimates for secondary succession but are not suitable for mature forest biomass estimates due to data saturation problems. LiDAR can overcome TM’s shortcoming providing better biomass estimation performance but has not been extensively applied in practice due to data availability constraints. The uncertainty analysis indicates that various sources affect the performance of forest biomass/carbon estimation. With that said, the clear dominate sources of uncertainty are the variation of input sample plot data and data saturation problem related to optical sensors. A possible solution to increasing the confidence in forest biomass estimates is to integrate the strengths of multisensor data.
Long-Term Survival after Gamma Knife Radiosurgery in a Case of Recurrent Glioblastoma Multiforme: A Case Report and Review of the Literature
Authors: Thumma Sudheer R. , Elaimy Ameer L. , Daines Nathan , Mackay Alexander R. , Lamoreaux Wayne T. , Fairbanks Robert K. , Demakas John J. , Cooke Barton S. , Lee Christopher M.
Published: April 2012

The management of recurrent glioblastoma is highly challenging, and treatment outcomes remain uniformly poor. Glioblastoma is a highly infiltrative tumor, and complete surgical resection of all microscopic extensions cannot be achieved at the time of initial diagnosis, and hence local recurrence is observed in most patients. Gamma Knife radiosurgery has been used to treat these tumor recurrences for select cases and has been successful in prolonging the median survival by 8–12 months on average for select cases. We present the unique case of a 63-year-old male with multiple sequential recurrences of glioblastoma after initial standard treatment with surgery followed by concomitant external beam radiation therapy and chemotherapy (temozolomide). The patient was followed clinically as well as with surveillance MRI scans at every 2-3-month intervals. The patient underwent Gamma Knife radiosurgery three times for 3 separate tumor recurrences, and the patient survived for seven years following the initial diagnosis with this aggressive treatment. The median survival in patients with recurrent glioblastoma is usually 8–12 months after recurrence, and this unique case illustrates that aggressive local therapy can lead to long-term survivors in select situations. We advocate that each patient treatment at the time of recurrence should be tailored to each clinical situation and desire for quality of life and improved longevity.
Merged Search Algorithms for Radio Frequency Identification Anticollision
Authors: Shih Bih-Yaw , Chen Cheng-Wu , Chen Chen-Yuan , Lo Ta-Wei
Published: April 2012

Nowadays, the Radio Frequency Identification (RFID) system enables the control of many devices over an open communication infrastructure ranging from a small home area network to the global Internet. Moreover, a variety of consumer products are tagged with remotely low‐cost readable identification electromagnetic tags to replace Bar Codes. Applications such as automatic object tracking, inventory and supply chain management, and Web appliances were adopted for years in many companies. The arbitration algorithm for RFID system is used to arbitrate all the tags to avoid the collision problem with the existence of multiple tags in the interrogation field of a transponder. A splitting algorithm which is called Binary Search Tree (BST) is well known for multitags arbitration. In the current study, a splitting‐based schema called Merged Search Tree is proposed to capture identification codes correctly for anticollision. Performance of the proposed algorithm is compared with the original BST according to time and power consumed during the arbitration process. The results show that the proposed model can reduce searching time and power consumed to achieve a better performance arbitration.
Periodic Solutions of a Cohen‐Grossberg‐Type BAM Neural Networks with Distributed Delays and Impulses
Authors: Liu Qiming , Xu Rui
Published: April 2012

A class of Cohen‐Grossberg‐type BAM neural networks with distributed delays
and impulses are investigated in this paper. Sufficient conditions to guarantee the uniqueness
and global exponential stability of the periodic solutions of such networks are established
by using suitable Lyapunov function, the properties of M‐matrix, and some suitable mathematical transformation. The results in this paper improve the earlier publications.
Aberrant L1 Cell Adhesion Molecule Affects Tumor Behavior and Chemosensitivity in Anaplastic Thyroid Carcinoma
Authors: Kim Koon Soon , Min Jeong-Ki , Liang Zhe Long , Lee Kyungmin , Lee Jung Uee , Bae Kwang-Hee , Lee Min Hee , Lee Seong Eun , Ryu Min Jeong , Kim Soung Jung , Kim Yong Kyoung , Choi Min Jeong , Jo Young Suk , Kim Jin-Man , Shong Minho
Published: April 2012

Purpose: Anaplastic thyroid carcinoma (ATC) is one of the most invasive human cancers and has a poor prognosis. Molecular targets of ATC that determine its highly aggressive nature remain unidentified. This study investigated L1 cell adhesion molecule (L1CAM) expression and its role in tumorigenesis of ATCs.

Experimental Design: Expression of L1CAM in thyroid cancer was evaluated by immunohistochemical analyses of tumor samples from patients with thyroid cancer. We investigated the role of L1CAM in proliferation, migration, invasion, and chemoresistance using short hairpin RNA (shRNA) knockdown experiments in human ATC cell lines. Finally, we evaluated the role of L1CAM on tumorigenesis with ATC xenograft assay in a nude mouse model.

Results: L1CAM expression was not detectable in normal follicular epithelial cells of the thyroid or in differentiated thyroid carcinoma. In contrast, analysis of ATC samples showed specifically higher expression of L1CAM in the invasive area of the tumor. Specific knockdown of L1CAM in the ATC cell lines, FRO and 8505C, caused a significant decrease in the proliferative, migratory, and invasive capabilities of the cells. Suppression of L1CAM expression in ATC cell lines increased chemosensitivity to gemcitabine or paclitaxel. Finally, in an ATC xenograft model, depletion of L1CAM markedly reduced tumor growth and increased the survival of tumor-bearing mice.

Conclusions: We report that L1CAM is highly expressed in the samples taken from patients with ATCs. L1CAM plays an important role in determining tumor behavior and chemosensitivity in cell lines derived from ATCs. Therefore, we suggest that L1CAM may be an important therapeutic target in patients with ATCs. Clin Cancer Res; 18(11); 3071–8. ©2012 AACR.
Simplifying the Energy Balance Message for Breast Cancer Prevention
Authors: Fabian Carol J.
Published: April 2012

Simple prevention messages based on understandable biologic principles are likely to be adopted. The long-held premise that postmenopausal obesity elevates, but premenopausal obesity reduces, risk for breast cancer is confusing to the public. Furthermore, decades of positive energy balance may be difficult to suddenly reverse at the time of the menopause. In this issue (beginning on page 583), Cecchini et al. suggest that obesity may also be a risk factor for pre-menopausal women 35 and older who have additional risk factors for breast cancer. Although the relative impact of dysregulated energy metabolism depends on many factors including age, hormonal milieu, and competing risk factors, as well as how it is measured, avoiding weight gain after age 30 is increasingly being recognized as a simple way to reduce risk of breast cancer. Cancer Prev Res; 5(4); 511–4. ©2012 AACR.
Venous thromboembolism prevention with fondaparinux 1.5 mg in renally impaired patients undergoing major orthopaedic surgery
Authors: Mismetti Patrick , Samama Charles-Marc , Rosencher Nadia , Vielpeau Claude , Nguyen Philippe , Deygas Beatrice , Presles Emilie , Laporte Silvy ,   for The PROPICE Study Group
Published: April 2012

Despite the need for effective and safe thromboprophylactic drugs for patients with renal impairment, clinical trial data on anticoagulant agents are limited in this population. The study aim was to assess in the real-world setting the use of the once-daily 1.5 mg reduced dosage regimen of fondaparinux available for this context. In this prospective cohort study, patients with a creatinine clearance (CrCl) of 20–50 ml/ minute, undergoing total hip (THR) or knee (TKR) replacement or hip fracture surgery (HFS) received fondaparinux thromboprophylaxis. Main clinical outcomes were bleeding (major/clinically relevant nonmajor), symptomatic venous thromboembolism (VTE) and death. Overall, 442 patients (353 women; median age: 82 years; 39.4% in ASA class ≥3; mean ± SD CrCl: 39.0 ± 8.0 ml/minute; 78% with additional risk factors for bleeding), undergoing THR (43.7%), TKR (27.6%), or HFS (28.7%) received fondaparinux 1.5 mg for a mean ± SD duration of 16.0 ± 12.5 days. At postoperative day 10, the rates (95% confidence interval) of major bleeding, clinically relevant bleeding and symptomatic VTE were 4.5% (2.8–6.9), 0.5% (0.1–1.6) and 0.5% (0.05–1.62), respectively; no fatal bleeding, bleeding into a critical organ, pulmonary embolism or proximal deep-vein thrombosis occurred. Corresponding rates at one month were 5.2%, 0.7% and 0.7%. One-month mortality was 2.3% (0.9–3.6). This large clinical prospective study provides for the first time, under conditions reflecting “real-world” routine clinical practice, data on the bleeding and VTE risks of thromboprophylaxis with fondaparinux 1.5 mg after major orthopaedic surgery in renally impaired patients. It shows that these patients constitute a very elderly and fragile population.

ClinicalTrials.gov number, NCT00555438
Paying Too Much for Energy? The True Costs of Our Energy Choices
Authors: Greenstone Michael , Looney Adam
Published: April 2012

Energy consumption is critical to economic growth and quality of life. America's energy system, however, is malfunctioning. The status quo is characterized by a tilted playing field, where energy choices are based on the visible costs that appear on utility bills and at gas pumps. This system masks the “external” costs arising from those energy choices, including shorter lives, higher health care expenses, a changing climate, and weakened national security. As a result, we pay unnecessarily high costs for energy. New “rules of the road” could level the energy playing field. Drawing from our work for The Hamilton Project, this paper offers four principles for reforming U.S. energy policies in order to increase Americans' well-being.
Stimulating Energy Technology Innovation
Authors: Moniz Ernest J.
Published: April 2012

The innovation system has interrelated components of invention, translation, adoption, and diffusion. Energy technology innovation has lagged that in other domains, and there is a compelling public interest in picking up the pace through appropriate government action. Government and universities are creating new approaches in the invention and translation stages. The Department of Energy (DOE) has implemented novel programs such as ARPA-E. Research universities have moved closer to the marketplace through more diversified industry collaboration models, such as convening research-sponsoring companies both horizontally in a sector and vertically across the innovation chain. Much more needs to be done to expand public-private partnerships and to define a broadly accepted government role in the adoption and diffusion stages. An administration-wide Quadrennial Energy Review process, informed by technical analysis and social science research, offers the best opportunity in this regard.
Starting Before the Beginning: Precreation Discourse in Colossians
Authors: Jeal Roy R.
Published: April 2012

Abstract

This essay identifies and examines the function of the language in the Letter to the Colossians that Sociorhetorical Interpretation calls “precreation rhetorolect.” This rhetorolect is a mode of discourse that indicates, counterintuitively, realities behind and prior to what is present. Consequently, it starts before the beginning by describing the protological existence and activity of God and his son. In Colossians this rhetorolect occurs in 1:15–18a, 1:19 and 2:9. Precreation language in these passages describes the protological intelligence and activity that leads to what is right and real in the present. It is employed to persuade audiences to maintain their focus on Christ, the correct person. No other supposed divine or eminent powers, whether cosmic or human, have the precreational existence, the preeminent position, or the divine power to do what the son/Christ does in rescuing, reconciling, and providing a foundation for people. The rhetorolect draws on aspects of its intertextural environment of ideas to convey meaning that shapes its audiences. The rhetorical power of the discourse is found not only in what the texts say, but in how they say it and in what they do to their audiences. This study of the precreation language in Colossians describes how the discourse is employed to make a case, an argument. The precreation language aims at a wisdom conclusion, that is, at correct, mature belief and behaviour.
Student Success
Authors: Mullin Christopher M.
Published: April 2012

This article examines measures of student success, with a focus on how they apply to community colleges. A conceptual framework is presented as a way of facilitating thinking about and accurately grounding discussions of student success. The article closes with an examination of emerging concepts related to the measurement of student success in higher education generally and at community colleges particularly.
A Gender-bender of a Life – So Far
Authors: Wootton Janet
Published: April 2012

The author reflects on her own experience as a congregational minister and in national and international positions of leadership, alongside working in Feminist Theology and the development of inclusive language in worship. As a minister and leader, she has found herself cast in a male role, and thus prevented from modeling women’s leadership in a way that might empower other women.
Activity of pomalidomide in patients with immunoglobulin light-chain amyloidosis
Authors: Dispenzieri Angela , Buadi Francis , Laumann Kristina , LaPlant Betsy , Hayman Suzanne R. , Kumar Shaji K. , Dingli David , Zeldenrust Steven R. , Mikhael Joseph R. , Hall Robert , Rajkumar S. Vincent , Reeder Craig , Fonseca Rafael , Bergsagel P. Lief , Stewart A. Keith , Roy Vivek , Witzig Thomas E. , Lust John A. , Russell Stephen J. , Gertz Morie A. , Lacy Martha Q.
Published: April 2012

Immunoglobulin light-chain (AL) amyloidosis is a rare, incurable plasma cell disorder. Its therapy has benefited immensely from the expanding drug armamentarium available for multiple myeloma. Pomalidomide in combination with weekly dexamethasone (Pom/dex) is active among patients with relapsed myeloma. In the present study, we explored the Pom/dex combination in patients with previously treated AL. Patients were eligible for this prospective phase 2 trial if they had had at least one prior regimen and if they had reasonably preserved organ function. Patients were treated with oral Pom/dex. Thirty-three patients were enrolled. The median age was 66 years. Median time from diagnosis to on-study was 37 months. Eighty-two percent had cardiac involvement. The confirmed hematologic response rate was 48%, with a median time to response of 1.9 months. Organ improvement was documented in 5 patients. The median overall and progression-free survival rates were 28 and 14 months, respectively; the 1-year overall and progression-free survival rates were 76% and 59%, respectively. There was a discordance between the hematologic response and the N-terminal pro-brain natriuretic peptide response. The most common grade 3-5 adverse events, regardless of attribution, were neutropenia and fatigue. We conclude that pomalidomide appears to be a valuable drug covering an unmet clinical need in patients with previously treated AL. The trial is registered at www.clinicaltrials.gov as NCT00558896.
Genetic variations in genes involved in heparan sulphate biosynthesis are associated with Plasmodium falciparum parasitaemia: a familial study in Burkina Faso
Authors: Atkinson Alexandre , Garnier Séverine , Afridi Sarwat , Fumoux Francis , Rihet Pascal
Published: April 2012

Background

There is accumulating evidence that host heparan sulphate proteoglycans play an important role in the life cycle of Plasmodium through their heparan sulphate chains, suggesting that genetic variations in genes involved in heparan sulphate biosynthesis may influence parasitaemia. Interestingly, Hs3st3a1 and Hs3st3b1 encoding enzymes involved in the biosynthesis of heparan sulphate are located within a chromosomal region linked to Plasmodium chabaudi parasitaemia in mice. This suggests that HS3ST3A1 and HS3ST3B1 may influence P. falciparum parasitaemia in humans.

Methods

Polymorphisms within HS3ST3A1 and HS3ST3B1 were identified in 270 individuals belonging to 44 pedigrees and living in Burkina Faso. Linkage and association between parasitaemia and the polymorphisms were assessed with MERLIN and FBAT. A genetic interaction analysis was also conducted based on the PGMDR approach.

Results

Linkage between P. falciparum parasitaemia and the chromosomal region containing HS3ST3A1 and HS3ST3B1 was detected on the basis of the 20 SNPs identified. In addition, rs28470223 located within the promoter of HS3ST3A1 was associated with P. falciparum parasitaemia, whereas the PGMDR analysis revealed a genetic interaction between HS3ST3A1 and HS3ST3B1. Seventy-three significant multi-locus models were identified after correcting for multiple tests; 37 significant multi-locus models included rs28470223, whereas 38 multi-locus models contained at least one mis-sense mutation within HS3ST3B1.

Conclusion

Genetic variants of HS3ST3A1 and HS3ST3B1 are associated with P. falciparum parasitaemia. This suggests that those variants alter both the function of heparan sulphate proteoglycans and P. falciparum parasitaemia.
Investing in African research training institutions creates sustainable capacity for Africa: the case of the University of the Witwatersrand School of Public Health masters programme in epidemiology and biostatistics
Authors: Kellerman Ronel , Klipstein-Grobusch Kerstin , Weiner Renay , Wayling Steven , Fonn Sharon
Published: April 2012

Background

Improving health in Africa is a high priority internationally. Inadequate research capacity to produce local, relevant research has been identified as a limitation to improved population health. Increasing attention is being paid to the higher education sector in Africa as a method of addressing this; evidence that such investment is having the desired impact is required. A 1998 3-year investment by the Special Programme for Research and Training in Tropical Diseases (TDR) in research training at the School of Public Health, University of the Witwatersrand, South Africa was reviewed to assess its' impact.

Methods

A descriptive cross-sectional survey of the 70 students registered for the masters programme in epidemiology & biostatistics from 2000-2005 was conducted. Data were collected from self-administered questionnaires.

Results

Sixty percent (42/70) of students responded. At the time of the survey 19% of respondents changed their country of residence after completion of the masters course, 14% migrated within Africa and 5% migrated out of Africa. Approximately half (47%) were employed as researchers and 38% worked in research institutions. Sixty percent reported research output, and four graduates were pursuing PhD studies. Government subsidy to higher education institutions, investments of the University of the Witwatersrand in successful programmes and ongoing bursaries for students to cover tuition fees were important for sustainability.

Conclusions

Investing in African institutions to improve research training capacity resulted in the retention of graduates in Africa in research positions and produced research output. Training programmes can be sustained when national governments invest in higher education and where that funding is judiciously applied. Challenges remain if funding for students bursaries is not available.
Wnt3 and Wnt3a are required for induction of the mid-diencephalic organizer in the caudal forebrain
Authors: Mattes Benjamin , Weber Sabrina , Peres João , Chen Qing , Davidson Gary , Houart Corinne , Scholpp Steffen
Published: April 2012

Background

A fundamental requirement for development of diverse brain regions is the function of local organizers at morphological boundaries. These organizers are restricted groups of cells that secrete signaling molecules, which in turn regulate the fate of the adjacent neural tissue. The thalamus is located in the caudal diencephalon and is the central relay station between the sense organs and higher brain areas. The mid-diencephalic organizer (MDO) orchestrates the development of the thalamus by releasing secreted signaling molecules such as Shh.

Results

Here we show that canonical Wnt signaling in the caudal forebrain is required for the formation of the Shh-secreting MD organizer in zebrafish. Wnt signaling induces the MDO in a narrow time window of 4 hours - between 10 and 14 hours post fertilization. Loss of Wnt3 and Wnt3a prevents induction of the MDO, a phenotype also observed upon blockage of canonical Wnt signaling per se. Pharmaceutical activation of the canonical Wnt pathways in Wnt3/Wnt3a compound morphant embryos is able to restore the lack of the MDO. After blockage of Wnt signaling or knock-down of Wnt3/Wnt3a we find an increase of apoptotic cells specifically within the organizer primordium. Consistently, blockage of apoptosis restores the thalamus organizer MDO in Wnt deficient embryos.

Conclusion

We have identified canonical Wnt signaling as a novel pathway, that is required for proper formation of the MDO and consequently for the development of the major relay station of the brain - the thalamus. We propose that Wnt ligands are necessary to maintain the primordial tissue of the organizer during somitogenesis by suppressing Tp53-mediated apoptosis.
Black/Queer/Diaspora at the Current Conjuncture
Authors: Allen Jafari S.
Published: April 2012

This essay sketches the parameters of black/queer/diaspora ethics, aesthetics, and methodologies vis-à-vis conjunctural moments in black queer studies, women of color feminisms, queer of color critique, queer theory, and on-the-ground expressive practices. This genealogical matrix of the present moment argues that black/queer/diaspora work's love ethic, and radical roots in black and women of color feminisms, uniquely constructs it as an organic project of multivalent and multiscalar reclamation, revisioning, and futurity toward producing deeply humane and capacious analyses that both reflect “real life” on the ground and speculate on liberatory models—projecting our imaginations forward, toward possible futures.
Extract from “Water, Shoulders, Into the Black Pacific”
Authors: Tinsley Omise'eke Natasha
Published: April 2012

In the last twenty years, the geographic and conceptual space that Paul Gilroy dubbed the Black Atlantic—a network of transnational, transoceanic histories linking people of African descent in West Africa, the Caribbean, North America, and Europe—has emerged as the subject of deepening scholarly and creative reflections in England and the United States. But the Atlantic is by no means the only or most important body of water whose currents have moved African diaspora history. If Africans' forced Atlantic passage ushered in a colonial era that violently connected Africa and the Americas to Europe, Africans' travel to and on the Pacific as sailors, soldiers, dockworkers, and curious voyagers traced other kinds of crossings: linkages between black Atlantic subjects and Mexico, Native America, Polynesia, Micronesia, the Philippines, and other sites of flow through the global South. “Water, Shoulders, Into the Black Pacific” looks to innovate discussions of the African diaspora by tracing one possible route of this less-explored oceanography. Where does the black Atlantic meet the black Pacific? What would it mean to chart a story of the African diaspora not through the triangle trade crisscrossing that first ocean but as a continual navigation of many bodies of water—Atlantic, Caribbean, Gulf of Mexico, Mississippi, Pacific—and many waves of migration? These are some of the questions explored in this work of historical fiction, which draws from oral histories to imagine intersections of migration, work, and desire experienced by African/Haitian American women who came from New Orleans, Louisiana, to Richmond, California, to work in Kaiser's shipyards during World War II. Narrating erotic encounters between black female shipbuilders, the piece meditates on the changing and repeating meanings of shipmate relationships between African diasporics, and choosing fiction as the space to explore these relationships, experiments with how imaginative work can destabilize and “queer” received stories of race, nationality, gender, and sexuality.
“My Father Didn't Have a Dick”
Authors: Richardson Matt
Published: April 2012

Using Jackie Kay's novel Trumpet, this essay looks at the “social death” of black queerness, a positionality situated outside the nation and outside blackness, as a site from which to explore what it would mean for black men to embrace the feminine within themselves. Although the concept of social death gives us information about the condition of the slave, it also helps inform the contours of the structural position of blackness well after the formal end of slavery. The essay focuses on the relationship between novel's protagonist, Joss, a black Scottish transman, and his son, Colman, and the potential offered by queer subjectivity to imagine possibilities denied by the heteropatriarchial nation-state. Joss's queerness exposes the impossibility of black manhood to occupy a position of liberal citizenship and Colman's recognition of the structural vulnerability of diasporic black manhood brought to his attention in his realization of Joss's queerness. The improvisational element of jazz enables Joss to perform and achieve his black masculinity, and that improvisation opens up space for Colman to accept femininity as an insurgent possibility for black manhood.
Queer Histories and the Global City
Authors: Diaz Robert G.
Published: April 2012

This essay reviews three books that center on the globalized city as a key site for unpacking disparate queer cultures. Two of the books discussed make an explicit effort to deterritorialize queer historiography outside the global North. They focus on the everyday experiences of postcolonial subjects in Cape Town and Hong Kong. In a moment of intensified counterterrorism, necropolitical nationalism, and resurgent yet covert forms of empire, both works have much to say about how the lives of sexual minorities are simultaneously affected by and resist Western imperialism. Thus they also enter into an already ongoing debate in contemporary queer studies that challenges the normalization of queer politics as a product of expanding capital both locally and abroad. All three books trace the shifting forms of the nation-state and how it affects the lived experiences of queer populations in the city. In the process, they collectively refuse the seemingly axiomatic notion that queer subjects are always being homogenized by transnational capital and neoliberal cosmopolitanism. Rather, as Andrew Tucker suggests, the hybrid queer cultures present in the city demand a more nuanced understanding of how these communities are shaped by historically, geographically, and politically specific national and cosmopolitan ideals.