bluuebunny/crossref_metadata_2025 huggingface dataset:
Spin injection in a heterovalent structure with coupled quantum wells GaAs/(Al,Ga)As/(Zn,Mn)Se/ZnSe
Authors: Liaci F. , Kaibyshev V. Kh. , Toropov A. A. , Terent'ev Ya. V. , Mukhin M. S. , Klimko G. V. , Gronin S. V. , Sedova I. V. , Sorokin S. V. , Ivanov S. V.
Published: May 2012

In this report we present the study, by means of low‐temperature magneto‐optical measurements, of the spin transport dynamics in a heterovalent MBE‐grown III‐V/II‐VI structure under optical pumping. The structure consists of two coupled GaAs quantum wells (QWs) of 100 Å and 50 Å surrounded by (Al,Ga)As barriers, a heterovalent (Al,Ga)As/ZnSe interface, a 10 nm (Zn,Mn)Se spin aligner, and a 70 nm thick ZnSe cap layer. We obtain values of about 30% at 4.5 T for the degree of circular polarization. These results give some hints on the design improvements needed for higher spin‐filtering efficiency. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Stark effects of ZnO thin film and ZnO/ZnMgO quantum wells
Authors: Sato K. , Abe T. , Fujinuma R. , Yasuda K. , Yamaguchi T. , Kasada H. , Ando K.
Published: May 2012

We have investigated external electric field dependent Stark effects of ZnO thin film and ZnO/ZnMgO QWs by electroreflectance (ER) spectroscopy to develop electroabsorption modulators. The ZnO single film and ZnO/ZnMgO QWs were grown by plasma‐assisted molecular beam epitaxy (PA‐MBE). ZnO single film exhibited red‐shift of 8 meV by applying external bias at 18 K. This red‐shift is due to Stark effect in a low electric field, but it was changed to Franz‐Keldysh effect in a high electric field region. We confirmed a large blue‐shift of 39 meV for ZnO/ZnMgO QWs by external bias at room temperature. This energy shift, originated from quantum confined Stark effect (QCSE) in ZnO/ZnMgO QWs, proved a large exciton binding energy of this system. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of dopant transport rate upon photoluminescence and electrical properties of phosphorus‐doped ZnMgTe layers grown by MOVPE
Authors: Saito K. , Saeki T. , Tanaka T. , Guo Q. X. , Nishio M.
Published: May 2012

p‐type doping of Zn1‐xMgx Te has been investigated by metalorganic vapour phase epitaxy using tris‐dimethylaminophosphorus as a dopant source. The photoluminescence (PL) and electrical properties of the as‐grown and post‐annealed layers have been clarified as a function of the dopant transport rate. In PL spectra at 4.2 K, the strong donor acceptor pair emission vanished and instead enhancement of P acceptor‐related excitonic emission and/or appearance of free‐to‐bound emission were observed for all the layers by the post‐annealing treatment. In accordance with the PL behavior, the hole concentration at room temperature of the annealed layers was significantly enhanced from 2×1015∼2×1016 cm‐3 to 5×1016∼2×1018 cm‐3 by a maximum factor of ∼600. The enhanced hole concentration shows saturation tendency with increasing dopant transport rate. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Density functional theory study of ordered defect Cu‐(In,Ga)‐Se compounds
Authors: Zhao Hanyue , Kumar Mukesh , Persson Clas
Published: May 2012

CuIn1–xGaxSe2 is used as absorber material in thin‐film photovoltaics. Presence of defect arrays of 2VCu– + XCu2+ complexes (X = In or Ga) in the material results in the formation of ordered defect phases, like for instance Cu(In1–xGax)3Se5 and Cu(In1–xGax)5Se8. An understanding of these defects phases is of considerably importance since they can strongly affect the performance of the solar cell. Density functional theory calculation with a hybrid functional is carried out to study the electronic structures and optical properties of these ordered defect phases. Fundamental properties, such as the band bowing, the band alignment and the absorption coefficients, are presented, and their dependence on material composition is discussed (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effect of atomic‐layer‐deposited AlN on near‐surface InGaAs/GaAs structures
Authors: Mattila Päivi , Bosund Markus , Jussila Henri , Tuomi Turkka , Riikonen Juha , Huhtio Teppo , Lipsanen Harri , Sopanen Markku
Published: May 2012

Near‐surface InGaAs/GaAs quantum well and strain‐induced InGaAs/GaAs quantum dot structures are coated with AlN by plasma‐enhanced atomic layer deposition. Due to its relatively low fabrication temperature (<300 °C), AlN is an interesting candidate for the coating of strain‐induced quantum dots whose covering has been challenging in the past. As these quantum dots are sensitive to changes in the strain field they are utilized to show that a 10‐nm‐thick layer of AlN does not affect the strain field inside the near‐surface InGaAs/GaAs structures. Both the integrated photoluminescence intensity and the spacing between quantum dot energy levels remain approximately unchanged when the structures are coated by AlN. All in all, the coating of InGaAs/GaAs strain‐induced quantum dot structures with AlN could pave the way for the first strain‐induced quantum dot based optical components (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of Te/Zn flux ratio on aluminium doped ZnTe grown by MBE on GaSb substrates
Authors: Zhang Qiang , Liu Xinyu , DiNezza Michael J. , Fan Jin , Ding D. , Furdyna Jacek K. , Zhang Yong‐Hang
Published: May 2012

Aluminum doped ZnTe epitaxial layers have been grown on GaSb substrates by molecular beam epitaxy under different Te/Zn flux ratios, while the flux ratio is varied by keeping Te flux constant and changing Zn flux. The Te/Zn flux ratio ∼0.9 leads to the narrowest full width at half maximum of x‐ray diffraction rocking curve. Indium deposition is applied to improve the contact conductivity, characterized by current‐voltage measurements. The effect of annealing in forming gas (5% H2+ 95% Ar) has been studied and the secondary ion mass spectrometry results indicate Zn vacancies are suppressed in the order of 2 magnitudes by decreasing Te/Zn flux ratio from 2 to 0.5. This study assists the understanding and realization of effective n‐type doping of ZnTe by the approach of suppressing Zn vacancies (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
β‐Eudesmol Induces JNK‐Dependent Apoptosis through the Mitochondrial Pathway in HL60 Cells
Authors: Li Yanchun , Li Te , Miao Caixia , Li Jianchun , Xiao Wei , Ma Enlong
Published: May 2012

β‐eudesmol, a natural sesquiterpenol present in a variety of Chinese herbs, is known to inhibit the proliferation of human tumor cells. However, the molecular mechanisms of the effect of β‐eudesmol on human tumor cells are unknown. In the present study, we report the cytotoxic effect of β‐eudesmol on the human leukemia HL60 cells and its molecular mechanisms. The cytotoxic effect of β‐eudesmol on HL60 cells was associated with apoptosis, which was characterized by the presence of DNA fragmentation. β‐eudesmol‐induced apoptosis was accompanied by cleavage of caspase‐3, caspase‐9, and poly (ADP‐ribose) polymerase; downregulation of Bcl‐2 expression; release of cytochrome c from mitochondria; and decrease in mitochondrial membrane potential (MMP). Activation of c‐Jun N‐terminal kinases (JNK) mitogen‐activated protein kinases was observed in β‐eudesmol‐treated HL60 cells, and the inhibitor of JNK blocked the β‐eudesmol‐induced apoptosis, downregulation of Bcl‐2, and the loss of MMP. These data suggest that β‐eudesmol induces apoptosis in HL60 cells via the mitochondrial apoptotic pathway, which is controlled through JNK signaling. Copyright © 2012 John Wiley & Sons, Ltd.
Contaminant Hepatotoxins as Culprits for Kava Hepatotoxicity – Fact or Fiction?
Authors: Teschke Rolf , Sarris Jerome , Lebot Vincent
Published: May 2012

The culprit of kava hepatotoxicity will continue to remain a mystery in humans, if the underlying reaction is of idiosyncratic, unpredictable, and dose‐independent nature due potentially to some metabolic aberration in a few individuals emerging from kava use. In addition, kava hepatotoxicity is presently not reproducible experimentally in preclinical models, as demonstrated by studies showing whole kava extracts are not hepatotoxic. This led us to propose our ‘working hypothesis’ that contaminant hepatotoxins including moulds might have caused rare kava hepatotoxicity in humans. Further studies are now warranted to proof or disproof our working hypothesis, because kava hepatotoxicity possibly based on contaminant hepatotoxins could be a preventable disease. In the meantime, however, for minimizing toxicity risk in kava users, a pragmatic approach should focus on the medicinal use of an aqueous extract derived from peeled rhizomes and roots of a non‐mouldy noble kava cultivar, limited to maximum 250‐mg kavalactones daily for acute or intermittent use. Copyright © 2012 John Wiley & Sons, Ltd.
Resveratrol Protects Cortical Neurons against Microglia‐mediated Neuroinflammation
Authors: Zhang Feng , Wang Hui , Wu Qin , Lu Yuanfu , Nie Jing , Xie Xiaolong , Shi Jingshan
Published: May 2012

Neuroinflammation is closely associated with the pathogenesis of neurological disorders. The hallmark of neuroinflammation is considered to be microglial activation. Therefore, inhibition of microglial activation might hold a promising therapy for neurological disorders. Resveratrol, a natural non‐flavonoid polyphenol found in grapes and red wine, has been recognized as a bioactive agent with potential benefit for health. Several lines of evidence show that resveratrol could exert neuroprotection against ischemia, seizure, and neurodegenerative diseases. However, the mechanisms underlying its beneficial neuroprotective effects are poorly defined. Here, by using rat primary cortical neuron‐glia cultures, results showed that resveratrol attenuated lipopolysaccharide (LPS)‐induced cortical neurotoxicity. Further studies revealed that microglia were responsible for resveratrol‐mediated neuroprotection. Resveratrol significantly inhibited LPS‐induced microglial activation and subsequent production of multiple pro‐inflammatory and cytotoxic factors such as tumor necrosis factor‐α, nitric oxide, and interleukin‐1β. Collectively, resveratrol produced neuroprotection against microglia‐induced neurotoxicity. Thus, resveratrol might represent a potential benefit for the treatment of inflammation‐related neurological disorders. Copyright © 2012 John Wiley & Sons, Ltd.
A simple method for the removal of dissolved organic matter and δ15N analysis of NO3– from freshwater
Authors: Huber Benjamin , Bernasconi Stefano M. , Pannatier Elisabeth Graf , Luster Jörg
Published: May 2012

RATIONALE

Stable isotopes of nitrogen in nitrate (NO3–) are frequently used to identify nitrate sources and to study nitrogen (N) transformation processes, but the measurement methods available are generally rather labor intensive and/or costly, and dissolved organic matter (DOM) can interfere with the δ15N signature of nitrate. We therefore have developed a simple cleanup procedure for freshwater samples with low nitrate and high DOM concentrations.

METHODS

Nitrate and DOM are extracted from a freeze‐dried water sample by using a concentrated sodium hydroxide solution. By the subsequent addition of acetone, two liquid layers are formed, and nitrate migrates into the acetone while DOM remains in the concentrated NaOH solution, thus separating the nitrate from the DOM. For nitrogen isotope analysis, purified nitrate salts are combusted at 1030 °C to produce N2 gas in an elemental analyzer (EA) coupled to an isotope ratio mass spectrometer (IRMS).

RESULTS

With this novel technique up to 99% of DOM could be removed from river water and soil solutions. The method has been tested for sample amounts as small as 4 µmol NO3– with a precision of <0.1‰ (1SD). Nitrate standards are reproduced accurately without any blank correction.

CONCLUSIONS

The benefits of this method are the lack of interferences derived from DOM on the δ15N signature and the ease of sample preparation. Copyright © 2012 John Wiley & Sons, Ltd.
Master–slave robotic platform and its feasibility study for micro‐neurosurgery
Authors: Mitsuishi Mamoru , Morita Akio , Sugita Naohiko , Sora Shigeo , Mochizuki Ryo , Tanimoto Keiji , Baek Young Min , Takahashi Hiroki , Harada Kanako
Published: May 2012

Background

Microsurgery is a widely performed process in neurosurgery. However, it is difficult for surgeons because manipulating small and long instruments under a microscope often restricts dexterity. Hand tremors are also an issue, as the accuracy required for microsurgery is very high.

Method

A master–slave robotic platform has been developed for neurosurgery. A position–orientation decoupled design was employed to enhance positioning accuracy, and a smooth trajectory generation method was developed.

Result

The robotic tasks exhibited improved positioning accuracy compared to manual tasks. Anastomoses of 0.3 and 0.5 mm artificial vessels were successfully performed in end‐to‐end and end‐to‐side fashion.

Conclusion

With the robotic platform, the surgeon was able to perform a fine and complex task, which is very difficult with manual operation. The robotic system showed sufficient accuracy and dexterity, but with a longer task completion time. Further improvement of the dexterity and user interface is expected to realize better performance. Copyright © 2012 John Wiley & Sons, Ltd.
AFM Feature Definition for Neural Cells on Nanofibrillar Tissue Scaffolds
Authors: Tiryaki Volkan M. , Khan Adeel A. , Ayres Virginia M.
Published: May 2012

Summary: A diagnostic approach is developed and implemented that provides clear feature definition in atomic force microscopy (AFM) images of neural cells on nanofibrillar tissue scaffolds. Because the cellular edges and processes are on the same order as the background nanofibers, this imaging situation presents a feature definition problem. The diagnostic approach is based on analysis of discrete Fourier transforms of standard AFM section measurements. The diagnostic conclusion that the combination of dynamic range enhancement with low‐frequency component suppression enhances feature definition is shown to be correct and to lead to clear‐featured images that could change previously held assumptions about the cell–cell interactions present. Clear feature definition of cells on scaffolds extends the usefulness of AFM imaging for use in regenerative medicine. SCANNING 34: 316–324, 2012. © 2012 Wiley Periodicals, Inc.
Does three‐dimensional power Doppler ultrasound predict histopathological findings of uterine fibroids? A preliminary study
Authors: Minsart A.‐F. , Ntoutoume Sima F. , Vandenhoute K. , Jani J. , Van Pachterbeke C.
Published: May 2012

Objectives

To compare three‐dimensional (3D) power Doppler sonographic characteristics of fibroids with histopathological parameters.

Methods

We evaluated sonographically 73 fibroids before myomectomy or hysterectomy. For each, the total fibroid volume, a shell of 3  mm and a 1‐cm3 spherical sample from the most vascularized area on subjective assessment were captured. 3D power Doppler vascularization index (VI), flow index (FI) and vascularization flow index (VFI) were generated in the acquired volumes. The degree of cellularity, ischemic necrosis and fibrosclerosis, as well as CD31 and Ki‐67 staining for vascular density and proliferation index, respectively, were estimated using the surgical sample. Pathological data were considered as dependent variables and ultrasound data as independent variables in multivariable logistic regression models including patients' characteristics.

Results

A high histological ‘cellular activity score’, combining hypercellularity, a fibrosclerosis rate < 25% and positive Ki‐67 staining, was statistically related in multivariate analyses to high 3D power Doppler VI in spherical samples (odds ratio (OR), 1.1 (95% CI, 1.0–1.3), P < 0.05) and VFI (OR, 1.3 (95% CI, 1.0–1.8), P < 0.05). Positive CD31 staining was statistically related to high 3D power Doppler VI in spherical samples (OR, 1.1 (95% CI, 1.0–1.3), P < 0.05). In contrast, ischemic necrosis was statistically related to low 3D power Doppler VI in the total volume (OR, 0.6 (95% CI, 0.4–1.0), P < 0.05) and VFI (OR, 0.4 (95% CI, 0.1–1.1), P < 0.05).

Conclusion

Vascular density, ischemic necrosis and histological cellular activity score are statistically significantly associated with some 3D power Doppler indices. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.
Organogenesis of the vertebrate heart
Authors: Miquerol Lucile , Kelly Robert G.
Published: May 2012

Organogenesis of the vertebrate heart involves a complex sequence of events initiating with specification and differentiation of myocardial and endocardial cells in anterior lateral mesoderm shortly after gastrulation, followed by formation and rightward looping of the early heart tube. During looping, the heart tube elongates by addition of second heart field progenitor cells from adjacent pharyngeal mesoderm at the arterial and venous poles. Progressive differentiation is controlled by intercellular signaling events between pharyngeal mesoderm, foregut endoderm, and neural crest‐derived mesenchyme. Regulated patterns of myocardial gene expression and proliferation within the embryonic heart drive morphogenesis of atrial and ventricular chambers, while cardiac cushions, precursors of the definitive valves, form in the atrioventricular and outflow regions. In amniotes, separate systemic and pulmonary circulatory systems arise by septation and remodeling events that divide the atria and ventricles into left and right chambers. Cardiac neural crest cells play a key role in dividing the arterial pole of the heart into the ascending aorta and pulmonary trunk. During the remodeling phase the definitive cardiac conduction system, that coordinates the heartbeat, is established. In addition, the epicardium, critical for regulated ventricular growth and development of the coronary vasculature, spreads over the surface of the heart as an epithelium from which cells invade the myocardium to give rise to diverse cell types including fibroblasts and smooth muscle cells. Cardiogenesis thus involves highly coordinated development of multiple cell types and insight into the different lineage contributions and molecular regulation of each of these steps is expanding rapidly.WIREs Dev Biol2013, 2:17–29. doi: 10.1002/wdev.68

This article is categorized under:

Vertebrate Organogenesis > Musculoskeletal and Vascular
Rare syndromes of the head and face—Pierre Robin sequence
Authors: Tan Tiong Yang , Farlie Peter G.
Published: May 2012

Pierre Robin sequence (PRS) is an association of clinical features consisting of mandibular hypoplasia, cleft secondary palate, and glossoptosis leading to obstructive apnea and feeding difficulties. PRS can occur as an isolated condition or can be found in association with a range of other features in a number of conditions including Treacher collins and Stickler syndromes. The frequent association of the PRS triad suggests a common underlying developmental mechanism which impacts on each of these tissues. Isolated PRS is typically sporadic but when familial usually exhibits autosomal dominant inheritance. The term PRS is applied on the basis of the pattern of malformation rather than etiology and growing evidence indicates that the initiating genetic lesion is variable. Various chromosomal anomalies have been associated with PRS including loci on chromosomes 2, 4, and 17. Associations with genes including SOX9, a number of collagen genes and work with animal models suggest the phenotype derives from a cartilage defect during early facial growth. However, alternative theories have been proposed and these highlight the difficulty of characterising congenital anomalies of craniofacial development in which multiple etiologies can result in very similar phenotypes. WIREs Dev Biol 2013, 2:369–377. doi: 10.1002/wdev.69

For further resources related to this article, please visit the WIREs website.
Understanding multimodal biological decisions from single cell and population dynamics
Authors: Selvarajoo Kumar
Published: May 2012

Modern techniques on single‐cell and ‐molecule resolution reveal that gene and protein expressions between cells of an otherwise identical group are stochastic in time, and clonal population of cells display heterogeneity in the abundance of a given protein per cell at any measured time. Today, combinatorially, stochasticity and heterogeneity are considered as biological noise and are essential for generating phenotypic variations, cell fate decisions and amplification of molecular signals. Here, several works from experimental and theoretical aspects that show multimodal biological decisions at single cell and population level are reviewed. The emerging lessons from these studies suggest that, for yielding multimodal decisions, living systems are guided by well‐defined nonlinear deterministic processes which are sensitive to specific range of biological parameters. WIREs Syst Biol Med 2012 doi: 10.1002/wsbm.1175

This article is categorized under:

Biological Mechanisms > Cell Fates
Mg3[M(CN)6]2·xH2O with M = Fe, Co: Synthesis, Crystal Structure, and Hydrogen Sorption
Authors: Jiménez‐Gallegos Juan , Roque Jorge , Yee‐Madeira Hernani , Reguera Edilso
Published: May 2012

The titled materials were obtained neutralizing in situ prepared aqueous solutions of H3[M(CN)6] (M = Fe, Co) by adding Mg(OH)2 and evaporating the solvent under vacuum. Their crystal structure was solved and refined from powder X‐ray diffraction data. The two solids crystallize with a cubic unit cell, in the Pm$\bar{3}$m space group, which corresponds to an ordered distribution of [M(CN)6] vacancies. The materials structure is preserved when the crystal water is removed by moderated heating. The formed open porous framework was evaluated from nitrogen and hydrogen adsorption isotherms. The amount of hydrogen adsorbed is similar to that found for transition metal Prussian blue analogues. The structural study was complemented with infrared, thermo‐gravimetric, and Mössbauer spectroscopy data.
Production of a thermostable alcohol dehydrogenase from Rhodococcus ruber in three different yeast species using the Xplor®2 transformation/expression platform
Authors: Giersberg Martin , Degelmann Adelheid , Bode Rüdiger , Piontek Michael , Kunze Gotthard
Published: May 2012

The Xplor®2 transformation/expression platform was employed for comparative assessment of three different yeast species as hosts for synthesis of a thermostable nicotinamide adenine dinucleotide (NAD+)-dependent medium-chain alcohol dehydrogenase from Rhodococcus ruber strain 219. Using yeast ribosomal DNA (rDNA) integrative expression cassettes (YRCs) and yeast integrative expression cassettes (YICs) equipped with a selection-marker module and one, two or four expression modules for transformation of auxotrophic Arxula adeninivorans, Hansenula polymorpha, and Saccharomyces cerevisiae strains, quantitative comparison of the yield of recombinant alcohol dehydrogenase RR-ADH6Hp in all three species was carried out. In all cases, the RR-ADH6H gene was expressed under the control of the strong constitutive A. adeninivorans-derived TEF1 promoter, which functions in all yeast species analyzed. Recombinant RR-ADH6Hp accumulated intracellularly in all strains tested. The best yields of active enzyme were obtained from A. adeninivorans, with S. cerevisiae producing intermediate amounts. Although H. polymorpha was the least efficient producer overall, the product obtained was most similar to the enzyme synthesized by R. ruber 219 with respect to its thermostability.
Attitudes and Practices Among Internists Concerning Genetic Testing
Authors: Klitzman Robert , Chung Wendy , Marder Karen , Shanmugham Anita , Chin Lisa J. , Stark Meredith , Leu Cheng‐Shiun , Appelbaum Paul S.
Published: May 2012

Many questions remain concerning whether, when, and how physicians order genetic tests, and what factors are involved in their decisions. We surveyed 220 internists from two academic medical centers about their utilization of genetic testing. Rates of genetic utilizations varied widely by disease. Respondents were most likely to have ordered tests for Factor V Leiden (16.8 %), followed by Breast/Ovarian Cancer (15.0 %). In the past 6 months, 65 % had counseled patients on genetic issues, 44 % had ordered genetic tests, 38.5 % had referred patients to a genetic counselor or geneticist, and 27.5 % had received ads from commercial labs for genetic testing. Only 4.5 % had tried to hide or disguise genetic information, and <2 % have had patients report genetic discrimination. Only 53.4 % knew of a geneticist/genetic counselor to whom to refer patients. Most rated their knowledge as very/somewhat poor concerning genetics (73.7 %) and guidelines for genetic testing (87.1 %). Most felt needs for more training on when to order tests (79 %), and how to counsel patients (82 %), interpret results (77.3 %), and maintain privacy (80.6 %). Physicians were more likely to have ordered a genetic test if patients inquired about genetic testing (p < .001), and if physicians had a geneticist/genetic counselor to whom to refer patients (p < .002), had referred patients to a geneticist/genetic counselor in the past 6 months, had more comfort counseling patients about testing (p < .019), counseled patients about genetics, larger practices (p < .032), fewer African‐American patients (p < .027), and patients who had reported genetic discrimination (p < .044). In a multiple logistic regression, ordering a genetic test was associated with patients inquiring about testing, having referred patients to a geneticist/genetic counselor and knowing how to order tests. These data suggest that physicians recognize their knowledge deficits, and are interested in training. These findings have important implications for future medical practice, research, and education.
8‐[2‐(2‐Pentyl‐Cyclopropylmethyl)‐Cyclopropyl]‐Octanoic Acid and Its Diastereomers Improve Age‐Related Cognitive Deterioration
Authors: Kanno Takeshi , Yaguchi Takahiro , Shimizu Tadashi , Tanaka Akito , Nishizaki Tomoyuki
Published: May 2012

Racemic 8‐[2‐(2‐pentyl‐cyclopropylmethyl)‐cyclopropyl]‐octanoic acid (DCP‐LA), a linoleic acid derivative with cyclopropane rings instead of cis‐double bonds, contains possible four diastereomers such as α,α‐, α,β‐, β,α‐, and β,β‐DCP‐LA. The present study examined the effect of racemic and diastereomeric DCP‐LA on age‐related learning and memory disorders using accelerated‐senescence‐prone mice 8 (SAMP8) and accelerated‐senescence‐resistant mice 1 (SAMR1). In the water maze test, the acquisition and retention latencies for SAMP8 mice were significantly longer than the latency for SAMR1 mice, indicating spatial learning and memory impairment for SAMP8 mice. All the racemic (1 mg/kg, per os) and diastereomeric DCP‐LA (0.25 mg/kg, per os) significantly shortened the acquisition latency for SAMP8 mice, and racemic, α,α‐ and α,β‐DCP‐LA significantly shortened the retention latency, with the advantage greater than the acetylcholine (ACh) esterase inhibitor galanthamine. The results of the present study show that all the racemic and diastereomeric DCP‐LA, has the potential to improve age‐related learning and memory deterioration, the potential varying among them.
Statistical Security for Social Security
Authors: Soneji Samir , King Gary
Published: May 2012

The financial viability of Social Security, the single largest U.S. government program, depends on accurate forecasts of the solvency of its intergenerational trust fund. We begin by detailing information necessary for replicating the Social Security Administration’s (SSA’s) forecasting procedures, which until now has been unavailable in the public domain. We then offer a way to improve the quality of these procedures via age- and sex-specific mortality forecasts. The most recent SSA mortality forecasts were based on the best available technology at the time, which was a combination of linear extrapolation and qualitative judgments. Unfortunately, linear extrapolation excludes known risk factors and is inconsistent with long-standing demographic patterns, such as the smoothness of age profiles. Modern statistical methods typically outperform even the best qualitative judgments in these contexts. We show how to use such methods, enabling researchers to forecast using far more information, such as the known risk factors of smoking and obesity and known demographic patterns. Including this extra information makes a substantial difference. For example, by improving only mortality forecasting methods, we predict three fewer years of net surplus, $730 billion less in Social Security Trust Funds, and program costs that are 0.66% greater for projected taxable payroll by 2031 compared with SSA projections. More important than specific numerical estimates are the advantages of transparency, replicability, reduction of uncertainty, and what may be the resulting lower vulnerability to the politicization of program forecasts. In addition, by offering with this article software and detailed replication information, we hope to marshal the efforts of the research community to include ever more informative inputs and to continue to reduce uncertainties in Social Security forecasts.
Cancer cachexia and anabolic interventions: a case report
Authors: Dillon Edgar L. , Basra Gurjot , Horstman Astrid M. , Casperson Shanon L. , Randolph Kathleen M. , Durham William J. , Urban Randall J. , Diaz-Arrastia Concepcion , Levine Lyuba , Hatch Sandra S. , Willis Maurice , Richardson Gwyn , Sheffield-Moore Melinda
Published: May 2012

Background

Standard‐of‐care (SOC) cancer treatments are primarily aimed at reducing size and progression of a tumor. There is a need for successful supplemental anabolic therapies to combat cancer cachexia in addition to these SOC treatment modalities. Anabolic interventions, including testosterone and amino acid supplements, may be beneficial in reducing and/or reversing muscle wasting in these patient populations.

Methods

A 48‐year‐old Caucasian female with recurrent cervical cancer was scheduled to receive three 21‐day cycles of cisplatin and topetecan chemotherapy. She qualified, consented, and enrolled into a blinded interventional pilot study where she received daily whey protein (10 g, three times per day with meals) and a weekly injection of testosterone enanthate (100 mg intramuscular) before and during the SOC chemotherapy treatment period. Body composition, serum inflammatory markers, mixed muscle protein synthesis and breakdown rates, physical function, fatigue, and quality of life were assessed before and after the intervention period.

Results

Body composition, as assessed by an increase in body weight and lean body mass and reduction in fat mass; physical function; fatigue; and quality of life each improved across the entire intervention period despite general increases in inflammatory markers and no improvements in muscle protein turnover towards the end of the intervention.

Conclusions

Concomitant treatment of oral amino acids and testosterone may be a viable therapeutic option for fighting cachexia and improving body composition and quality of life during chemotherapeutic treatment of recurrent cervical cancer. These positive outcomes may be attainable over time despite overall poor inflammatory status.
Contactless Laser-Assisted Patterning of Surfaces for Bio-Adhesive Microarrays
Authors: Perez-Hernandez H. , Paumer T. , Pompe T. , Werner C. , Lasagni A. F.
Published: May 2012

Micropatterned surfaces with cell adhesive areas, delimited by protein repellent microstructures, are in high demand for its potential use as relevant biological assays. This is not only because such surfaces allow directing cell growth in a spatially localized and restricted manner, but also because they can be used to elucidate basic cell growth and orientation mechanisms. Here, it is presented a laser-assisted micropatterning technique to fabricate large area microstructures of poly (ethylene glycol) hydrogel onto a cell adhesive surface: a biofunctional maleic anhydride copolymer. By varying photoinitiator, laser intensity, copolymer as well as the hydrogel layer thickness, the optimum conditions to produce high quality features were found. The suitability of these micropatterned substrates for bioassay applications was proved by cell adhesion studies. The introduced procedure could be used to prepare a broad range of microarrays for certain bioanalytical approaches and to create different types of biofunctional surfaces.
Hinge sequences as signaling agents?
Authors: Stec Boguslaw
Published: May 2012

We report an unexpected finding of common structural principles in two unrelated signaling systems: the FAS death domain transformation that initializes the extrinsic apoptotic pathway and signaling by calmodulin bending. The location and design of the hinge is postulated to be a general principle for creating potential signaling event. We suggest that already existing tool can predict the existence of such a hinge and formulate the hypothesis that the internal instabilities designed into the hinge sequences are necessary devices in effective signaling events.
Impact of Ankle Bracing on Skill Performance in Recreational Soccer Players
Authors: Putnam Alison R. , Bandolin Shakira N. , Krabak Brian J.
Published: May 2012

Objective

To determine the effect of ankle braces on kicking accuracy, speed, and agility in competitive, nonelite soccer players. We hypothesized that the use of ankle bracing would significantly decrease performance in soccer‐specific drills immediately after use but not after acclimation to the brace.

Design

A prospective randomized controlled trial.

Setting

University.

Participants

Twenty healthy recreational adult soccer players (5 men and 15 women; mean age, 23 ± 4.8 years) without a history of lower extremity injury in the past 6 months. All the subjects completed the study.

Methods

The subjects completed a set of performance measures (ie, accuracy shooting at a target, 40‐yard dash, S180° run, and T test) with an McDavid 199 Lightweight ankle brace (test subjects) and without an ankle brace (control subjects) during 2 testing sessions spaced 7‐10 days apart. Between the 2 testing sessions, the subjects wore the ankle brace on at least 4 occasions while participating in athletic activities to ensure that a learning effect occurred.

Main Outcome Measurements

Outcomes included kicking accuracy (accuracy shooting at a target) and speed and agility (time to complete a 40‐yard dash, S180° run, and T test).

Results

No significant difference in performance was found for the accuracy in shooting at a target, 40‐yard dash, S180° run, and T test (P > .05) with and without an ankle brace during a session and between sessions.

Conclusions

Ankle braces did not significantly affect performance in speed, agility, or kicking accuracy in healthy, competitive, recreational soccer athletes.
Eclogite–gneiss complex of the Muya block (East Siberia): age, mineralogy, geochemistry, and petrology
Authors: Shatsky V.S. , Sitnikova E.S. , Tomilenko A.A. , Ragozin A.L. , Koz’menko O.A. , Jagoutz E.
Published: May 2012

Results of study of eclogite–gneiss complex of the Muya Block (East Siberia) are presented. Several structural types of the studied eclogites have been recognized. Kyanitic eclogite has been found for the first time. The host granite-gneisses are two-mica and biotite varieties, mainly garnet-bearing. The exposure of eclogites from different depths of the subducted plate at the present-day denudation level might be the reason for the wide range of the equilibrium temperatures of the Muya block eclogites (590–740 °C). The Sm–Nd dating of the eclogites and host gneisses showed the Neoproterozoic age of high-pressure metamorphism (∼630 Ma). The model age (TDM) of the eclogites (720 Ma) differs considerably from the model age of the host gneisses (>1.3 Ga). The geochemical features of the eclogites point to the mobility of LILE (Rb, Cs, Ba, K) and LREE during their interaction with fluids, whereas the gneisses in the same process showed the mobility of LILE only. The oxygen isotope composition of minerals in the eclogites varies over a narrow range (δ18O = 5.5–3.9) and is close to the average mantle value, which evidences a negligible interaction between the eclogite protoliths and meteoric or sea water. The study of fluid inclusions in quartz from the eclogites and host gneisses showed a predominance of liquid-nitrogen inclusions in the former and carbon dioxide inclusions in the latter.
Mineralogy of pockets of the Malkhan tourmaline deposit (Transbaikalia): feldspars of the Sosedka vein
Authors: Zagorsky V.Ye.
Published: May 2012

A detailed study was given to the composition and structure of alkali feldspars from the pockets of the Sosedka pegmatite vein, a large source of gems within the Malkhan tourmaline deposit. The vein is of concentric-zonal structure. Three types of pockets were recognized by mineral composition: A—quartz–lepidolite–Mn–Li–Al–tourmaline (± pollucite, hambergite, borocookeite, boromuscovite, danburite, light pink beryl); B—quartz–adularia–axinite (± laumontite); and C—quartz and laumontite (± B-containing cookeite). Each type of pockets contains feldspars of specific composition and structure. This evidences that pockets formed in strongly different conditions, though some pockets of different types are localized as close as 0.5–2 m from each other within a zone. The reported data disagree with the common model implying the formation of zonal pegmatite bodies as a result of crystallization differentiation within the vein.
The Tsagan earthquake of 1862 on Lake Baikal revisited: a study of secondary coseismic soft-sediment deformation
Authors: Lunina O.V. , Andreev A.V. , Gladkov A.S.
Published: May 2012

Coseismic soft-sediment deformation has been studied by structural and tectononophysical methods in the Selenga Delta area shaken by the devastating M ∼ 7.5 Tsagan earthquake in 1862. Among the documented deformation structures (seismites), clastic dikes are the most reliable paleoseismic indicators. The dikes have their sizes and extent showing proximity to the primary coseismic rupture zone and are closely associated with faults of different hierarchic levels. The Tsagan event occurred under SW–NE extension as motion on a stepped system of normal faults dipping at 300°–350°, ∠45°–75°.

The amount of vertical motion measured against a reference layer in a trench reached 2.83 m, and the maximum dip displacement measured in a single fracture was 0.5 m. The earthquake was generated by the Delta Fault that dips at 60° on average to the northwest.

The distribution of quantitative parameters of brittle and brittle-plastic deformation has been analyzed along two profiles, and two new parameters were introduced: indices of mean intensity (I) of clastic dikes and microdikes; the new parameters were calculated by specially developed equations. Summation of significant peaks in all parameters (SUMspp) allowed contouring the zone of most intense soft-sediment deformation near Dubinino Village.

Deformation mostly propagated in the NE–SW and N–S directions. The location of the 1862 Tsagan earthquake at 52.35° N and 106.67° E was inferred from the SUMspp value taking into account the dip of the causative fault plane and the average origin depth of earthquakes in the Baikal rift. The approach we used is applicable to locating preinstrumental events.

The recurrence of large earthquakes in the area of Proval Bay (Lake Baikal) has been estimated to be 1120–1230 years proceeding from alternating deformed and undeformed sediments in the sections, their thicknesses and deposition rates according to radiocarbon dating. The seismic activity has been associated with the same fault which can generate M ≥ 7 events.
Motion and structure of atmospheric mesoscale baroclinic vortices: dry air and weak environmental shear
Authors: Päschke Eileen , Marschalik Patrik , Owinoh Antony Z. , Klein Rupert
Published: May 2012

A strongly tilted, nearly axisymmetric vortex in dry air with asymmetric diabatic heating is analysed here by matched asymptotic expansions. The vortex is in gradient wind balance, with vortex Rossby numbers of order unity, and embedded in a quasi-geostrophic (QG) background wind with weak vertical shear. With wind speeds of $60{{\ndash}}120~\mathrm{km} ~{\mathrm{h} }^{\ensuremath{-} 1} $, such vortices correspond to tropical storms or nascent hurricanes according to the Saffir–Simpson scale. For asymmetric heating, nonlinear coupling of the evolution equations for the vortex tilt, its core structure, and its influence on the QG background is found. The theory compares well with the established linear theory of precessing quasi-modes of atmospheric vortices, and it corroborates the relationship between vortex tilt and asymmetric potential temperature and vertical velocity patterns as found by Jones (Q. J. R. Meteorol. Soc., vol. 121, 1995, pp. 821–851) and Frank & Ritchie (Mon. Weath. Rev., vol. 127, 1999, pp. 2044–2061) in simulations of adiabatic tropical cyclones. A relation between the present theory and the local induction approximation for three-dimensional slender vortex filaments is established.
Global stability of multiple solutions in plane sudden-expansion flow
Authors: Lanzerstorfer Daniel , Kuhlmann Hendrik C.
Published: May 2012

The two-dimensional, incompressible flow in a plane sudden expansion is investigated numerically for a systematic variation of the geometry, covering expansion ratios (steps-to-outlet heights) from $0. 25$ to $0. 95$. By means of a three-dimensional linear stability analysis global temporal modes are scrutinized. In a symmetric expansion the primary bifurcation is stationary and two-dimensional, breaking the mirror symmetry with respect to the mid-plane. The secondary asymmetric flow experiences a secondary instability to different three-dimensional modes, depending on the expansion ratio. For a moderately asymmetric expansion only one of the two secondary flows (the connected branch) is realized at low Reynolds numbers. Since the perturbed secondary flow does not deviate much from the symmetric secondary flow, both secondary stability boundaries are very close to each other. For very small and very large expansion ratios an asymptotic behaviour is found for suitably scaled critical Reynolds numbers and wavenumbers. Representative instabilities are analysed in detail using an a posteriori energy transfer analysis to reveal the physical nature of the instabilities. Depending on the geometry, pure centrifugal and elliptical amplification processes are identified. We also find that the basic flow can become unstable due to the effects of flow deceleration, streamline convergence and high shear stresses, respectively.
Effects of tillage practices on pea leaf weevil (Sitona lineatus L., Coleoptera: Curculionidae) biology and crop damage: A farm-scale study in the US Pacific Northwest
Authors: Hanavan R.P. , Bosque-Pérez N.A.
Published: May 2012

The pea leaf weevil, Sitona lineatus L., is periodically a significant pest of pea, Pisum sativum L., in the Palouse region of northern Idaho and eastern Washington, USA. Previous on-station research demonstrated significantly greater adult pea leaf weevil colonization, immature survival, adult emergence and plant damage in conventional-tillage compared to no-tillage plots of pea. In experiments conducted during the 2006 and 2007 growing seasons, aerial and ground adult pea leaf weevil colonization of large-scale commercial pea fields under different tillage regimes in northern Idaho and eastern Washington was examined for the first time. Initial pea leaf weevil feeding damage, immature weevil densities and subsequent adult emergence from the fields were also assessed. During both years, significantly more adult pea leaf weevils were captured in conventional-tillage than in no-tillage fields during the crop establishment period in May. No-tillage soils remained wet longer in the spring and could not be planted by growers until later than conventional-tillage fields. Pea planted under conventional-tillage emerged earlier and had significantly greater feeding damage by the pea leaf weevil than no-tillage pea. Significantly, greater immature pea leaf weevil densities and subsequent adult emergence were observed in conventional-tillage than in no-tillage pea fields. Delayed development of root nodules in the cooler, moister conditions of no-tillage pea fields likely resulted in escape from attack and injury during the critical growth stages that ultimately influence yield. Results indicate that large-scale commercial no-tillage pea fields are less suitable for colonization and survival of the pea leaf weevil and suffer less weevil damage than fields under conventional tillage.
The effects of treatments with selected pesticides on viability and vigour of maize (Zea mays) seeds and seedling emergence in the presence ofFusarium graminearum
Authors: AVELING T. A. S. , GOVENDER V. , KANDOLO D. S. , KRITZINGER Q.
Published: May 2012

The quality of seed is dependent on two very broad aspects: how healthy (disease-free) a seed is and its field performance (germination and vigour). The objective of the present study was to evaluate the effect of pesticidal seed treatments of maize (Zea maysL.) on seed germination and vigour, and on greenhouse emergence in the presence ofFusarium graminearumSchw. Maize seeds were treated with four pesticides: Apron®XL (metalaxyl), Thiram (thiram), Celest®XL (fludioxonil, metalaxyl) and Apron®Star 42 WS (thiamethoxam, metalaxyl, difenoconazole). Viability and vigour of the treated seeds were determined. Thereafter, seeds were planted under greenhouse conditions. The control consisted of water-treated seeds. None of the pesticides reduced the standard germination under laboratory conditions and none had any effect on the quantity of leachate (measured as conductivity) or moisture content of the seeds. The different treatments also had no effect on germination or on seedling weight increase among treatments after rapid imbibition and there was no difference in germination among treatments following the cold test. The proportion of diseased plants harvested fromF. graminearuminoculated soil was significantly reduced by Apron®Star 42 WS and Celest®XL. The vigour tests indicated that none of the pesticides tested affected the seeds negatively and that plant biomass in the presence of the pathogen,F. graminearum, was increased after the application of the pesticides to the seeds, with the exception of seeds treated with Apron®XL.
PREVALENCE OF CONSANGUINEOUS MARRIAGES IN SOUTH SINAI, EGYPT
Authors: YAMAMAH G. , ABDEL-RAOUF E. , TALAAT A. , SAAD-HUSSEIN A. , HAMAMY H. , MEGUID N. A.
Published: May 2012

A total of 3961 married couples from six major geographical areas representing the South Sinai governorates in Egypt were studied to assess the rate of consanguineous marriage. The population of six selected areas (St Catherines, Nuweiba, Abu Rudeis, Ras Sudr, El Tor and Abu Zenima) were subdivided into Bedouin, urban and mixed populations. A questionnaire-based interview was conducted showing that the consanguinity rate in this region is 37.5%, with the highest rate recorded in Abu Rudeis (52.3%) and lowest rate in Nuweiba (24.1%). Consanguinity was significantly higher among the Bedouin population compared with the urban population in Abu Rudeis, Ras Sudr, El Tor and Abu Zenima, while in St Catherines and Nuweiba there was no statistically significant difference. Among consanguineous couples, 5%, 60% and 35% were double first cousins, first cousins and second cousins respectively. The mean inbreeding coefficient α of the studied population was 0.01845.