bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect Of Pre-freeze Addition Of Cysteine Hydrochloride And Reduced Glutathione On Post-thaw Sperm Parameters And Field Fertility In Jersey Crossbred Bull Semen
Authors: Perumal P , Selvaraju S , Barik A.K. , Mohanty D. N. , Das Srinibas , Mishra P.C.
Published: March 2012

The present study was aimed to assess the effect of pre-freeze addition of cysteine hydrochloride and glutathione (GSH) on post-thaw sperm functional parameters and field fertility. The experimental bulls aged 4 to 6 years were used for the present study. A total of 36 ejaculates, 6 ejaculates from each bull (n=6) were collected and divided in to three groups, group I (control), group II (5mM cysteine hydrochloride) and group III (5mM GSH). The extended semen samples were added with @5mM additives, filled in mini straw using automatic filling and sealing machine (IMV, France) and cryopreserved in liquid nitrogen. Post-freeze seminal traits were also recorded after thawing at 37oC for 30 seconds. Post thaw livability was significantly (p< 0.01) higher in GSH group as compared to cysteine and control groups. The loss of acrosomal integrity was significantly (p< 0.01) lower in GSH group than cysteine and control groups. Analysis of variance for post thaw motility parameters (Forward progressive and Total motility) has revealed that significant difference (p< 0.05) between the good and poor freezer in the group II and there was no difference in the group I and III under study at 0 and 1 hr incubation period and at 2 hrs the group III and at 4 hrs group I has revealed significance difference (p< 0.05).The curvilinear velocity (VCL) and amplitude of lateral head displacement (ALH) values were significantly (P<0.05) higher in GSH than the cysteine and control groups. The Mitochondrial membrane potential (per cent) had no significance difference between the treatment groups. The present study indicates that the addition of cysteine and GSH suggestive of reducing lipid peroxide levels. The conception rate (%) in glutathione (68) added semen was significantly (p>0.05) higher than cysteine (58) and control (49) groups. The post-thaw sperm progressive forward motility (r=0.4) had moderate but, no significant correlation with conception rate. However post-thaw VSL (r=0.7), loss of acrosomal integrity (r=-0.8) and mitochondrial membrane potential (r=0.9) had significant (p< 0.05) correlation with field fertility. The present study indicates that the use of glutathione as semen additives may be recommended for improving semen quality and overall augmentation of pregnancy in cows. The present study suggests that pre-freeze addition of glutathione was found to be better than cysteine in improving sperm fertility.
Misuse of Odds Ratios in Obesity Literature: An Empirical Analysis of Published Studies
Authors: Tajeu Gabriel S. , Sen Bisakha , Allison David B. , Menachemi Nir
Published: March 2012

Odds ratios (ORs) are widely used in scientific research to demonstrate the associations between outcome variables and covariates (risk factors) of interest, and are often described in language suitable for risks or probabilities, but odds and probabilities are related, not equivalent. In situations where the outcome is not rare (e.g., obesity), ORs no longer approximate the relative risk ratio (RR) and may be misinterpreted. Our study examines the extent of misinterpretation of ORs in Obesity and International Journal of Obesity. We reviewed all 2010 issues of these journals to identify all articles that presented ORs. Included articles were then primarily reviewed for correct presentation and interpretation of ORs; and secondarily reviewed for article characteristics that may have been associated with how ORs are presented and interpreted. Of the 855 articles examined, 62 (7.3%) presented ORs. ORs were presented incorrectly in 23.2% of these articles. Clinical articles were more likely to present ORs correctly than social science or basic science articles. Studies with outcome variables that had higher relative prevalence were less likely to present ORs correctly. Overall, almost one‐quarter of the studies presenting ORs in two leading journals on obesity misinterpreted them. Furthermore, even when researchers present ORs correctly, the lay media may misinterpret them as relative RRs. Therefore, we suggest that when the magnitude of associations is of interest, researchers should carefully and accurately present interpretable measures of association—including RRs and risk differences—to minimize confusion and misrepresentation of research results.
High-intensity exercise attenuates postprandial lipaemia and markers of oxidative stress
Authors: Gabriel Brendan , Ratkevicius Aivaras , Gray Patrick , Frenneaux Michael P. , Gray Stuart R.
Published: March 2012

Regular exercise can reduce the risk of CVD (cardiovascular disease). Although moderate-intensity exercise can attenuate postprandial TAG (triacylglycerol), high-intensity intermittent exercise might be a more effective method to improve health. We compared the effects of high-intensity intermittent exercise and 30 min of brisk walking on postprandial TAG, soluble adhesion molecules and markers of oxidative stress. Nine men each completed three 2-day trials. On day 1, subjects rested (control), walked briskly for 30 min (walking) or performed 5×30 s maximal sprints (high-intensity). On day 2, subjects consumed a high-fat meal for breakfast and 3 h later for lunch. Blood samples were taken at various times and analysed for TAG, glucose, insulin, ICAM-1 (intracellular adhesion molecule-1), VCAM-1 (vascular adhesion molecule-1), TBARS (thiobarbituric acid- reactive substances), protein carbonyls and β-hydroxybutyrate. On day 2 of the high-intensity trial, there was a lower (P<0.05) incremental TAG AUC (area under the curve; 6.42±2.24 mmol/l per 7 h) compared with the control trial (9.68±4.77 mmol/l per 7 h) with no differences during day 2 of the walking trial (8.98±2.84 mmol/l per 7 h). A trend (P=0.056) for a reduced total TAG AUC was also seen during the high-intensity trial (14.13±2.83 mmol/l per 7 h) compared with control (17.18±3.92 mmol/l per 7 h), walking showed no difference (16.33±3.51 mmol/l per 7 h). On day 2 of the high-intensity trial plasma TBARS and protein carbonyls were also reduced (P<0.05) when compared with the control and walking trials. In conclusion, high-intensity intermittent exercise attenuates postprandial TAG and markers of oxidative stress after the consumption of a high-fat meal.
Major Contributors to Hospital Mortality in Very-Low-Birth-Weight Infants: Data of the Birth Year 2010 Cohort of the German Neonatal Network
Authors: Stichtenoth G. , Demmert M. , Bohnhorst B. , Stein A. , Ehlers S. , Heitmann F. , Rieger-Fackeldey E. , Olbertz D. , Roll C. , Emeis M. , Mögel M. , Schiffmann H. , Wieg C. , Wintgens J. , Herting E. , Göpel W. , Härtel C.
Published: March 2012

The German Neonatal Network (GNN) is a prospective cohort study with the focus on long term development of very-low-birth-weight infants. It was the aim of this study to determine detailed information on causes of mortality in the GNN birth cohort 2010.

Major contributors to hospital mortality were recorded by the attending neonatologists for the cohort of very-low-birth-weight (VLBW) infants born in centres of the German Neonatal Network (GNN) in 2010. The data quality was approved by on-site monitoring.

2 221 VLBW infants were born in GNN centres in 2010, and death occurred in 221 infants. Male infants carried a higher risk than females (58.8% males among non-survivors vs. 51.7% among survivors, p=0.047). In 11 infants, the major contributor to death was not determined by the attending neonatologist. In 25 infants born at the limit of viability, comfort palliative care was primarily initiated and 14 infants had lethal malformations. The majority of non-survivors suffered from inflammatory diseases including sepsis- or necrotizing enterocolitis (NEC)-associated death (n=56). Respiratory pathology was a major contributor to death in 65 infants including 11 infants who died from pulmonary haemorrhage.

Potentially preventable complications of preterm birth such as sepsis, NEC and pulmonary haemorrhage predominate the major contributors to mortality in the GNN 2010 cohort. In order to decrease the rate of these associated deaths, future trials should focus on prophylaxis and therapy optimization strategies for these outcomes.
Experimental studies of the NaCs 53Π and 1(a)3Σ+ states
Authors: Ashman S. , McGeehan B. , Wolfe C. M. , Faust C. , Richter K. , Jones J. , Hickman A. P. , Huennekens J.
Published: March 2012

We report high resolution measurements of 372 NaCs 53Π0(v, J) ro-vibrational level energies in the range 0 ≤ v ≤ 22. The data have been used to construct NaCs 53Π0 potential energy curves using the Rydberg–Klein-Rees and inverted perturbation approximation methods. Bound-free 53Π0(v, J) → 1(a)3Σ+ emission has also been measured, and is used to determine the repulsive wall of the 1(a)3Σ+ state and the 53Π0 → 1(a)3Σ+ relative transition dipole moment function. Hyperfine structure in the 53Π0 state has not been observed in this experiment. This null result is explained using a simple vector coupling model.
Experimental investigation of transparent silicon carbide for atom chips
Authors: Huet Landry , Ammar Mahdi , Morvan Erwan , Sarazin Nicolas , Pocholle Jean-Paul , Reichel Jakob , Guerlin Christine , Schwartz Sylvain
Published: March 2012

We investigate some properties of an atom chip made of a gold microcircuit deposited on a transparent silicon carbide substrate. A favorable thermal behavior is observed in the presence of electrical current, twice as good as a silicon counterpart. We obtain one hundred million rubidium atoms in a magneto-optical trap with several of the beams passing through the chip. We point out the importance of coating of the chip against reflection to avoid a temperature-dependent Fabry-Perot effect. We finally discuss detection through the chip, potentially granting large numerical apertures, as well as some other potential applications.
Magnetic properties and thermal stability of (Fe,Co)-Mo-B-P-Si metallic glasses
Authors: Bhattacharya S. , Lass E. A. , Poon S. J. , Shiflet G. J. , Rawlings M. , Daniil M. , Willard M. A.
Published: March 2012

A series of ferromagnetic metallic glasses with compositions (Fe,Co)78Mo1(B,P,Si)21 are shown to possess good thermal stability and soft magnetic performance. The thermal stability inside the supercooled liquid temperature region was evaluated using Kissinger analysis of primary crystallization, time-temperature-transformation (TTT) diagrams, and the extent of the supercooled liquid region (ΔTx). The phosphorus-free alloy, Fe78Mo1B15Si6, had an activation energy (Ea) of 414 kJ/mol, ΔTx ∼ 50 K, and began devitrifying after about 1 min at 730 K. By way of comparison, the phosphorus-containing alloy, Fe78Mo1B13P6Si2, had an Ea of 440 kJ/mol, ΔTx ∼ 45 K, and began devitrification after 10 min at 730 K. High saturation magnetization (μ0Ms ∼ 1.45-1.55 T) and low coercivity (Hc ∼ 20 A/m) are demonstrated across the composition range. Core loss measurements of toroidal cores are shown to be less than 12 W/cm3 at 1 T, maximum induction amplitude (under both sinusoidal and square waveforms). Trends were established for magnetic and thermal stability as a function of metalloid and magnetic transition metal composition.
Development of flexure based 6-degrees of freedom parallel nano-positioning system with large displacement
Authors: Kang Dongwoo , Gweon Daegab
Published: March 2012

This paper details the development of a novel flexure jointed precision parallel nano-positioning system in combination with piezo-electric stepping motor for the application of precise optics alignment. The characteristics of the developed system are evaluated in this paper by the simulation and experiments. Based on the precision piezo-electric stepping motor and flexure joints, a high precision motion is obtained. Results of this paper include that of a translation resolution of 15 nm and a rotational resolution of 0.14 arc sec being achieved. In addition, the piezo-electric stepping motors provide a power-off hold characteristic to the system. Meanwhile, the parallel structure provides the high dynamic bandwidth of the lowest resonant frequency of 396.1 Hz. The symmetric structure is advantageous for thermal variation. To increase the motion range of the system, all of flexure joints are designed specially and the coupled workspace of ±2 mm × ±2 mm × ±2 mm × ±2° × ±2° × ±2° is achieved. The overall size of the designed system is Φ350 mm × 120 mm.
Evidence of critical balance in kinetic Alfvén wave turbulence simulations
Authors: TenBarge J. M. , Howes G. G.
Published: March 2012

A numerical simulation of kinetic plasma turbulence is performed to assess the applicability of critical balance to kinetic, dissipation scale turbulence. The analysis is performed in the frequency domain to obviate complications inherent in performing a local analysis of turbulence. A theoretical model of dissipation scale critical balance is constructed and compared to simulation results, and excellent agreement is found. This result constitutes the first evidence of critical balance in a kinetic turbulence simulation and provides evidence of an anisotropic turbulence cascade extending into the dissipation range. We also perform an Eulerian frequency analysis of the simulation data and compare it to the results of a previous study of magnetohydrodynamic turbulence simulations.
Hofmeister anionic effects on hydration electric fields around water and peptide
Authors: Kim Heejae , Lee Hochan , Lee Gayeon , Kim Haeyoung , Cho Minhaeng
Published: March 2012

Specific ion effects on water dynamics and local solvation structure around a peptide are important in understanding the Hofmeister series of ions and their effects on protein stability in aqueous solution. Water dynamics is essentially governed by local hydrogen-bonding interactions with surrounding water molecules producing hydration electric field on each water molecule. Here, we show that the hydration electric field on the OD bond of HOD molecule in water can be directly estimated by measuring its OD stretch infrared (IR) radiation frequency shift upon increasing ion concentration. For a variety of electrolyte solutions containing Hofmeister anions, we measured the OD stretch IR bands and estimated the hydration electric field on the OD bond to be about a hundred MV/cm with standard deviation of tens of MV/cm. As anion concentration increases from 1 to 6 M, the hydration electric field on the OD bond decreases by about 10%, indicating that the local H-bond network is partially broken by dissolved ions. However, the measured hydration electric fields on the OD bond and its fluctuation amplitudes for varying anions are rather independent on whether the anion is a kosmotrope or a chaotrope. To further examine the Hofmeister effects on H-bond solvation structure around a peptide bond, we examined the amide I′ and II′ mode frequencies of N-methylacetamide in various electrolyte D2O solutions. It is found that the two amide vibrational frequencies are not affected by ions, indicating that the H-bond solvation structure in the vicinity of a peptide remains the same irrespective of the concentration and character of ions. The present experimental results suggest that the Hofmeister anionic effects are not caused by direct electrostatic interactions of ions with peptide bond or water molecules in its first solvation shell. Furthermore, even though the H-bond network of water is affected by ions, thus induced change of local hydration electric field on the OD bond of HOD is not in good correlation with the well-known Hofmeister series. We anticipate that the present experimental results provide an important clue about the Hofmeister effect on protein structure and present a discussion on possible alternative mechanisms.
Numerical simulations of strong incompressible magnetohydrodynamic turbulence
Authors: Mason J. , Perez J. C. , Boldyrev S. , Cattaneo F.
Published: March 2012

Magnetised plasma turbulence pervades the universe and is likely to play an important role in a variety of astrophysical settings. Magnetohydrodynamics (MHD) provides the simplest theoretical framework in which phenomenological models for the turbulent dynamics can be built. Numerical simulations of MHD turbulence are widely used to guide and test the theoretical predictions; however, simulating MHD turbulence and accurately measuring its scaling properties is far from straightforward. Computational power limits the calculations to moderate Reynolds numbers and often simplifying assumptions are made in order that a wider range of scales can be accessed. After describing the theoretical predictions and the numerical approaches that are often employed in studying strong incompressible MHD turbulence, we present the findings of a series of high-resolution direct numerical simulations. We discuss the effects that insufficiencies in the computational approach can have on the solution and its physical interpretation.
An x-space magnetic particle imaging scanner
Authors: Goodwill Patrick W. , Lu Kuan , Zheng Bo , Conolly Steven M.
Published: March 2012

Magnetic particle imaging (MPI) is an imaging modality with great promise for high-contrast, high-sensitivity imaging of iron oxide tracers in animals and humans. In this paper, we present the first x-space MPI hardware and reconstruction software; show experimentally measured signals; detail our reconstruction technique; and present images of resolution and “angiography” phantoms.
Comparison of ammonia plasma and AlN passivation by plasma-enhanced atomic layer deposition
Authors: Mattila P. , Bosund M. , Huhtio T. , Lipsanen H. , Sopanen M.
Published: March 2012

Surface passivation of GaAs by ammonia plasma and AlN fabricated by plasma-enhanced atomic layer deposition are compared. It is shown that the deposition temperature can be reduced to 150 °C and effective passivation is still achieved. Samples passivated by AlN fabricated at 150 °C show four times higher photoluminescence intensity and longer time-resolved photoluminescence lifetime than ammonia plasma passivated samples. The passivation effect is shown to last for months. The dependence of charge carrier lifetime and integrated photoluminescence intensity on AlN layer thickness is studied using an exponential model to describe the tunneling probability from the near-surface quantum well to the GaAs surface.
X-ray phase imaging with a paper analyzer
Authors: Morgan Kaye S. , Paganin David M. , Siu Karen K. W.
Published: March 2012

We present a simple x-ray phase imaging method that utilizes the sample-induced distortion of a high contrast random intensity pattern to quantitatively retrieve the two-dimensional phase map at the exit surface of a coherently illuminated sample. This reference pattern is created by placing a sheet of sandpaper in the x-ray beam, with the sample-induced distortion observed after propagation to the detector, a meter downstream. Correlation analysis comparing a single “sample and sandpaper” image to a reference “sandpaper only” image produces two sensitive differential phase contrast images, giving the sample phase gradient in vertical and horizontal directions. These images are then integrated to recover the projected phase depth of the sample. The simple experimental set-up, retention of flux, and the need for only a single sample image per reconstruction suggest that this method is of value in imaging a range of dynamic processes at both synchrotron and laboratory x-ray sources.
Liquid crystal based nonlinear fishnet metamaterials
Authors: Minovich Alexander , Farnell James , Neshev Dragomir N. , McKerracher Ian , Karouta Fouad , Tian Jie , Powell David A. , Shadrivov Ilya V. , Hoe Tan Hark , Jagadish Chennupati , Kivshar Yuri S.
Published: March 2012

We study experimentally the nonlinear properties of fishnet metamaterials infiltrated with nematic liquid crystals and find that moderate laser powers result in significant changes of the optical transmission of the composite structures. We also show that the nonlinear response of our structure can be further tuned with a bias electric field, enabling the realization of electrically tunable nonlinear metamaterials.
Multiple solutions of the quasirelativistic Choquard equation
Authors: Melgaard M. , Zongo F.
Published: March 2012

We prove existence of multiple solutions to the quasirelativistic Choquard equation with a scalar potential.
Low energy electron beam induced vacancy activation in GaN
Authors: Nykänen H. , Suihkonen S. , Kilanski L. , Sopanen M. , Tuomisto F.
Published: March 2012

Experimental evidence on low energy electron beam induced point defect activation in GaN grown by metal-organic vapor phase epitaxy (MOVPE) is presented. The GaN samples are irradiated with a 5–20 keV electron beam of a scanning electron microscope and investigated by photoluminescence and positron annihilation spectroscopy measurements. The degradation of the band-to-band luminescence of the irradiated GaN films is associated with the activation of point defects. The activated defects were identified as in-grown Ga-vacancies. We propose that MOVPE-GaN contains a significant concentration of passive VGa-Hn complexes that can be activated by H removal during low energy electron irradiation.
Long-lived, room-temperature electron spin coherence in colloidal CdS quantum dots
Authors: Feng D. H. , Li X. , Jia T. Q. , Pan X. Q. , Sun Z. R. , Xu Z. Z.
Published: March 2012

Time-resolved Faraday rotation spectroscopy is used to study the electron spin coherence in colloidal CdS quantum dots. Long-lived spin coherence with dephasing time T2*>3ns has been found at room temperature. Spin dynamics unaffected by the faster carrier recombination suggests the spin signal coming from the residual electrons in the dots. A small external transverse magnetic field of 50 mT can extend T2* ∼ 2 times longer compared with that in zero magnetic field. Hyperfine interaction between electron and nuclear spins limits the dephasing time in zero or low magnetic field, while for higher magnetic fields, inhomogeneous dephasing becomes to dominate the spin dynamics.
Self-adaptive electronic contact between graphene and semiconductors
Authors: Zhong Haijian , Liu Zhenghui , Xu Gengzhao , Fan Yingmin , Wang Jianfeng , Zhang Xuemin , Liu Liwei , Xu Ke , Yang Hui
Published: March 2012

Understanding the contact properties of graphene on semiconductors is crucial to improving the performance of graphene optoelectronic devices. Here, we show that when graphene is in contact with a semiconductor, the charge carrier transport into graphene leads to a self-adaptive shift of the Fermi level, which tends to lower the barrier heights of the graphene contact to both n- and p-type semiconductors. A theoretical model is presented to describe the charge carrier transport mechanism and to quantitatively estimate the barrier heights. These results can benefit recent topical approaches for graphene integration in various semiconductor devices.
Modeling TGF-β signaling pathway in epithelial-mesenchymal transition
Authors: Laise Pasquale , Fanelli Duccio , Lió Pietro , Arcangeli Annarosa
Published: March 2012

The epithelial-mesenchymal transition (EMT) consists in a morphological change in epithelial cells characterized by the loss of the cell adhesion and the acquisition of mesenchymal phenotype. This process plays a crucial role in the embryonic development and in regulating the tissue homeostasis in the adult, but it proves also fundamental for the development of cancer metastasis. Experimental evidences have shown that the EMT depends on the TGF-β signaling pathway, which in turn regulates the transcriptional cellular activity. In this work, a dynamical model of the TGF-β pathway is proposed and calibrated versus existing experimental data on lung cancer A549 cells. The analysis combines Bayesian Markov Chain Monte Carlo (MCMC) and standard Ordinary Differential Equations (ODEs) techniques to interpolate the gene expression data via an iterative adjustments of the parameters involved. The kinetic of the Smad proteins phosphorylation, as predicted within the model is found in excellent agreement with available experiments, an observation that confirms the adequacy of the proposed mathematical picture.
Formation of AlGaN and GaN epitaxial layer with high p-carrier concentration by pulse supply of source gases
Authors: Aoyagi Yoshinobu , Takeuchi Misaichi , Iwai Sohachi , Hirayama Hideki
Published: March 2012

A drastic increase in the p-type carrier concentration and decrease in the activation energy of an acceptor are achieved by using a method of pulse supply of the source gases for AlGaN and GaN. This method offers a new way of producing a low-resistance p-AlGaN and p-GaN epitaxial layer.
Atomic-scale effects behind structural instabilities in Si lamellae during ion beam thinning
Authors: Holmström E. , Kotakoski J. , Lechner L. , Kaiser U. , Nordlund K.
Published: March 2012

The rise of nanotechnology has created an ever-increasing need to probe structures on the atomic scale, to which transmission electron microscopy has largely been the answer. Currently, the only way to efficiently thin arbitrary bulk samples into thin lamellae in preparation for this technique is to use a focused ion beam (FIB). Unfortunately, the established FIB thinning method is limited to producing samples of thickness above ∼20 nm. Using atomistic simulations alongside experiments, we show that this is due to effects from finite ion beam sharpness at low milling energies combined with atomic-scale effects at high energies which lead to shrinkage of the lamella. Specifically, we show that attaining thickness below 26 nm using a milling energy of 30 keV is fundamentally prevented by atomistic effects at the top edge of the lamella. Our results also explain the success of a recently proposed alternative FIB thinning method, which is free of the limitations of the conventional approach due to the absence of these physical processes.
Brownian rod scheme in microenvironment sensing
Authors: Gralinski Ian , Ng Tuck Wah
Published: March 2012

Fluctuations of freely translating spherical particles via Brownian motion should provide inexhaustible information about the micro-environment, but is beset by the problem of particles drifting away from the venue of measurement as well as colliding with other particles. We propose a scheme here to circumvent this in which a Brownian rod that lies in proximity to a cylindrical pillar is drawn in by a tuneable attractive force from the pillar. The force is assumed to act through the centre of each body and the motion exclusive to the x-y plane. Simulation studies show two distinct states, one in which the rod is moving freely (state I) and the other in which the rod contacts the cylinder surface (state II). Information about the micro-environment could be obtained by tracking the rotational diffusion coefficient Dθ populating in either of these two states. However, the magnitude of the normalized charge product in excess of 6.3x104 was found necessary for a rod of 6.81 × 0.93 μm2 (length × diameter) and 10μm diameter cylindrical pillar to minimize deviation errors. It was also found that the extent of spatial sensing coverage could be controlled by varying the charge level. The conditions needed to ascertain the rotational sampling for angle determination through the Hough transform were also discussed.
Host-guest interaction in cancer and a reason for the poor efficiency of the immune system in its detection and termination
Authors: Cerofolini G. F.
Published: March 2012

Organisms (like amoebae, bacteria, etc.), whose population in an unlimited nutritive medium would grow exponentially with time, behave often as aggressive strain with respect to higher organisms. Higher organisms provide a medium very different from the unlimited one considered above; among the various niches where the strain growth is possible, the circulatory system plays a special role. The topological structure of the circulatory system (two interlocked trees addressed to the delivery of O2 and nutritive substances to all tissues forming the higher organism and to the elimination of metabolic wastes) poses constraints to the growth of the strain population. The immune system is devoted to control and eventually to terminate the strain growing inside the organism. In many cases the immune system is sufficiently effective for that; there is a case, however, for which the immune system generally fails—cancer. In this work, after considering a few elementary properties of the growth of strains and higher organisms, I shall consider how the structure of the latter affects the population dynamics of cancer, and identify a possible reason why the immune system is so ineffective in recognizing cancer cells.
Local Indices of Segregation with Application to Social Segregation between London's Secondary Schools, 2003–08/09
Authors: Harris Richard
Published: March 2012

Segregation is a spatial outcome of spatial processes which, therefore, needs to be measured spatially. This is the axiom from which local indices of segregation are developed and applied to the patterns of admission observed for cohorts of pupils entering London's state-funded secondary schools in each of the years from 2003 to 2008. The indices—local indices of difference, isolation, and of concentration—are used to measure social segregation within education authorities, to detect differences between types of selecting and nonselecting schools, and, longitudinally, to consider changes over time. Sizeable differences in the proportions of pupils eligible for free school meals recruited by apparently competing schools are found, with selective schools especially and also faith schools underrecruiting such pupils. Although there is some evidence that social segregation has decreased over the period, the trend is considered to be an artefact of the use of free school meals as a measure of disadvantage—a measure which the author ultimately questions.
The Role of Foreign Direct Investment as a Structural Development Indicator of the Hierarchical World Economy
Authors: Dezzani Raymond J , Johansen Harley
Published: March 2012

The world-system perspective has been little employed for the examination of foreign direct investment (FDI) distributions in the world economy. We approach FDI distributions as a function of the structural hierarchy of the world economy. The goal is to examine some fundamental relationships between the structure of the world economy and the flows and stocks of FDI. A state-space approach is used such that the world-economy classification serves as a dependent variable to be explained by FDI behavior. An FDI capital distribution model is developed to generate hypotheses for statistical validation. Results of the analyses suggest that, while the world-economy classification accounts for a significant proportion of variability, FDI is more complex than the core–periphery capital distribution model predicts. Differences in average profit rate, investment risk, and investment purpose all serve to adjust variation in the FDI distributions. Investment risk exhibits a stable relationship among world-economy classes over at least a twenty-year period and seems to be a primary driver of investment behavior. FDI may therefore be a statistically reasonable covariate with country-level position in the world economy as well as a predictor of development potential.
Synthesis and Structural Studies of Tetrahedral [M(Ph2P(CH=CH)PPh2)2]BPh4 and [M(Ph2P(CH2)nPPh2)2]BPh4 (n = 2, 3) Complexes for M = Copper(I), Silver(I), and Gold(I)
Authors: Healy Peter C. , Loughrey Bradley T. , Williams Michael L.
Published: March 2012

Tetraphenylborate salts of the 1 : 2 tetrahedral bis(bidentate) complexes of copper(i), silver(i), and gold(i) with cis-bis(diphenylphosphino)ethene (dppey), [M(Ph2PCH=CHPPh2)2]BPh4, cis-bis(diphenylphosphino)ethane (dppe), and cis-bis(diphenylphosphino)propane (dppp), [M(Ph2P–R–PPh2)2]BPh4 (R = (CH2)2, (CH2)3), have been prepared and characterized by NMR spectroscopy, electrospray mass spectrometry, and single crystal X-ray structural analysis at 200 K. Structures of the dppey complexes as acetone solvates show the Cu and Ag complexes to be isostructural with the previously reported Au complex, crystallizing in space group P 21/n with a ~ 25.5, b ~ 15.6, and c ~ 34.2 Å, and β ~ 103°. Structures of the dppe complexes show the copper complex to crystallize in the chiral space group P21 with a 11.8954(5), b 20.1904(5), and c 14.8999(5) Å, and β 111.366(5)°. The Ag and Au complexes are isostructural, crystallizing in space group P21/c with a ~ 17.8, b ~ 17.6, and c ~ 20.9 Å, and β ~ 107°. Structures of the dppp complexes show the copper complex to crystallize in space group P21/c with a 17.8399(4), b 19.8803(4), and c 18.7165(3) Å, and β 102.197(2)°. The Ag and Au complexes are isostructural, crystallizing in space group P21/n with a ~ 17.7, b ~ 18.6, and c ~ 19.6 Å, and β ~ 100°. Across the three series of complexes, the M–P bond lengths increase in the order Cu < Au < Ag with Cu–P = 2.281(3)–2.314(1) Å, average 2.30(1) Å; Au–P = 2.363(1)–2.4322(8) Å, average 2.40(2) Å, and Ag–P = 2.445(1)–2.5303(5) Å average 2.49(2) Å.
Habitat use by corn mice (Calomys musculinus) in cropfield borders of agricultural ecosystems in Argentina
Authors: Simone Ivana , Provensal Cecilia , Polop Jaime
Published: March 2012

Context
Calomys musculinus (Cricetidae, Sigmodontinae) is a small rodent species widely distributed in Argentina and particularly abundant in agroecosystems of the Pampean region, where it is known to select border habitats over cropfields.

Aims
The aim of the present research was to assess habitat use by C. musculinus in cropfield borders. Assuming that the number of rodent captures in each border reflects the intensity of use, we intended to identify the habitat characteristics that would account for abundance differences among borders.

Methods
Seasonal trapping sessions were carried out in borders of the rural zone of Chucul, Córdoba. Environmental variables were registered from both field surveys and remote-sensing imagery. Generalised linear models were used to identify the habitat variables associated with C. musculinus habitat use.

Key results
General fit of the models was fairly good; spring, summer and autumn models explained more than 55% of the variation in C. musculinus abundance among borders. Individual plant species were significant predictors of C. musculinus abundance, but they varied with seasons, whereas tree cover and border width were significant predictors in most seasons studied. In general, rodent abundance was positively associated with peanut and maize crops or maize stubbles and negatively related to soybean or its stubbles. In the coldest seasons, rodent abundance increased with increasing land-surface temperature of the border.

Conclusions
Border use by C. musculinus appeared to respond to differences in border quality, which seems to be more affected by those environmental characteristics that entail a reduction of the predatory risk rather than by those that involve food supply. Crop-fields may partially afford C. musculinus food requirements.

Implications
Because C. musculinus is the natural reservoir of a zoonotic agent, the identification of the habitat characteristics affecting rodent population numbers in borders may be of crucial importance for the implementation of ecologically based rodent-management strategies aimed at reducing human–rodent contacts. We suggest that wide borders, particularly those contiguous to maize and peanut cropfields, should be understood as priority sites for the implementation of specific control actions.
Implications for collagen I chain registry from the structure of the collagen von Willebrand factor A3 domain complex
Authors: Brondijk T. Harma C. , Bihan Dominique , Farndale Richard W. , Huizinga Eric G.
Published: March 2012

Fibrillar collagens, the most abundant proteins in the vertebrate body, are involved in a plethora of biological interactions. Plasma protein von Willebrand factor (VWF) mediates adhesion of blood platelets to fibrillar collagen types I, II, and III, which is essential for normal haemostasis. High affinity VWF-binding sequences have been identified in the homotrimeric collagen types II and III, however, it is unclear how VWF recognizes the heterotrimeric collagen type I, the superstructure of which is unknown. Here we present the crystal structure of VWF domain A3 bound to a collagen type III-derived homotrimeric peptide. Our structure reveals that VWF-A3 interacts with all three collagen chains and binds through conformational selection to a sequence that is one triplet longer than was previously appreciated from platelet and VWF binding studies. The VWF-binding site overlaps those of SPARC (also known as osteonectin) and discodin domain receptor 2, but is more extended and shifted toward the collagen amino terminus. The observed collagen-binding mode of VWF-A3 provides direct structural constraints on collagen I chain registry. A VWF-binding site can be generated from the sequences RGQAGVMF, present in the two α1(I) chains, and RGEOGNIGF, in the unique α2(I) chain, provided that α2(I) is in the middle or trailing position. Combining these data with previous structural data on integrin binding to collagen yields strong support for the trailing position of the α2(I) chain, shedding light on the fundamental and long-standing question of the collagen I chain registry.
The protein expression landscape of the
Arabidopsis
root
Authors: Petricka Jalean J. , Schauer Monica A. , Megraw Molly , Breakfield Natalie W. , Thompson J. Will , Georgiev Stoyan , Soderblom Erik J. , Ohler Uwe , Moseley Martin Arthur , Grossniklaus Ueli , Benfey Philip N.
Published: March 2012

Because proteins are the major functional components of cells, knowledge of their cellular localization is crucial to gaining an understanding of the biology of multicellular organisms. We have generated a protein expression map of the
Arabidopsis
root providing the identity and cell type-specific localization of nearly 2,000 proteins. Grouping proteins into functional categories revealed unique cellular functions and identified cell type-specific biomarkers. Cellular colocalization provided support for numerous protein–protein interactions. With a binary comparison, we found that RNA and protein expression profiles are weakly correlated. We then performed peak integration at cell type-specific resolution and found an improved correlation with transcriptome data using continuous values. We performed GeLC-MS/MS (in-gel tryptic digestion followed by liquid chromatography-tandem mass spectrometry) proteomic experiments on mutants with ectopic and no root hairs, providing complementary proteomic data. Finally, among our root hair-specific proteins we identified two unique regulators of root hair development.
Agronomic avenues to maximize the benefits of rising atmospheric carbon dioxide concentrations in asian irrigated rice systems.
Authors: Yang L. , Peng S.
Published: March 2012

This chapter summarizes the adaptation strategies of rice crops under the predicted future elevated CO2 conditions by examining the use of different cultivars and crop management practices, such as crop density adjustment, fertilizer application, irrigation, control of insect pests, diseases and weeds. Recommendations for future research priorities are given.
Essay Review: Scientific Pluralism
Authors: Cat Jordi
Published: March 2012

The basic education of philosophers of science during the second half of the twentieth century was founded on the seven Rs: the three basic Rs and the topics of Rationality, Realism, Reductionism, and Relativism. The topic and ideas in this volume are foundational and challenging. They challenge and replace the ancient notion of philosophy as unified knowledge and the corresponding images of the tree of knowledge and encyclopedia forests.
Antiproliferative factor regulates connective tissue growth factor (CTGF/CCN2) expression in T24 bladder carcinoma cells
Authors: Matika Christina A. , Wasilewski Melissa , Arnott John A. , Planey Sonia Lobo
Published: March 2012

Antiproliferative factor (APF) is a sialoglycopeptide elevated in the urine of patients with interstitial cystitis (IC)—a chronic, painful bladder disease of unknown etiology. APF inhibits the proliferation of normal bladder epithelial and T24 bladder carcinoma cells in vitro by binding to cytoskeleton-associated protein 4 (CKAP4) and altering the transcription of genes involved in proliferation, cellular adhesion, and tumorigenesis; however, specific molecular mechanisms and effector genes that control APF's antiproliferative effects are unknown. In this study, we found that there was a 7.5-fold up-regulation of connective tissue growth factor (CTGF/CCN2) expression in T24 bladder carcinoma cells treated with APF. Western blot revealed a dose-dependent increase in CCN2 protein levels, with secretion into the culture medium after APF treatment. CCN2 overexpression enhanced APF's antiproliferative activity, whereas CCN2 knockdown diminished APF-induced p53 expression. Using a luciferase reporter construct, we found that APF treatment resulted in fivefold activation of the CCN2 proximal promoter and, of importance, that small interfering RNA–mediated knockdown of CKAP4 inhibited CCN2 upregulation. In addition, we demonstrate that CKAP4 translocates to the nucleus and binds to the CCN2 proximal promoter in an APF-dependent manner, providing evidence that CCN2 regulation by APF involves CKAP4 nuclear translocation and binding to the CCN2 promoter.
Improving Predictions using Ensemble Bayesian Model Averaging
Authors: Montgomery Jacob M. , Hollenbach Florian M. , Ward Michael D.
Published: March 2012

We present ensemble Bayesian model averaging (EBMA) and illustrate its ability to aid scholars in the social sciences to make more accurate forecasts of future events. In essence, EBMA improves prediction by pooling information from multiple forecast models to generate ensemble predictions similar to a weighted average of component forecasts. The weight assigned to each forecast is calibrated via its performance in some validation period. The aim is not to choose some “best” model, but rather to incorporate the insights and knowledge implicit in various forecasting efforts via statistical postprocessing. After presenting the method, we show that EBMA increases the accuracy of out-of-sample forecasts relative to component models in three applied examples: predicting the occurrence of insurgencies around the Pacific Rim, forecasting vote shares in U.S. presidential elections, and predicting the votes of U.S. Supreme Court Justices.
Novel Septoria Speckled Leaf Blotch Resistance Loci in a Barley Doubled-Haploid Population
Authors: Luckert Doris , Toubia-Rahme Hala , Steffenson Brian J. , Choo Thin-Meiw , Molnar Stephen J.
Published: March 2012

The genetics of resistance to Septoria speckled leaf blotch (SSLB), caused by Septoria passerinii, was studied in the Leger × CIho9831 barley doubled-haploid population. The 140 lines in the population segregated as 102 resistant and 38 susceptible, approximating a 3:1 ratio. A recombination map was developed using diversity arrays technology and other molecular markers. Quantitative trait locus (QTL) analysis demonstrated that resistance is primarily conferred either by having the CIho9831 allele at a QTL on 6HS or by having the CIho9831 allele at both of two QTLs on 3H and 2HL. In addition, ≈1/16 of the lines were resistant for unidentified reasons. This model predicts a resistant/susceptible ratio of 11:5, which fits the phenotypic observations. Minor QTLs were detected on 2HS and 1H. DNA sequences of linked markers suggest that the 6HS, 3H, and 2HS QTLs are part of resistance gene clusters and that the 6HS and 3H QTLs share homology. The 6HS QTL is identical to or closely linked to the SSLB resistance locus Rsp4 and the 1H QTL to the Rsp2 or Rsp3 locus. The 3H and 2HS QTLs are unique and offer new opportunities for pyramiding resistance genes through marker-assisted breeding for resistance to S. passerinii.
Objective Assessment of the Immediate Postoperative Analgesia Using Pupillary Reflex Measurement
Authors: Aissou Mourad , Snauwaert Aurelie , Dupuis Claire , Atchabahian Arthur , Aubrun Frederic , Beaussier Marc
Published: March 2012

Background

The evaluation of pain intensity during the immediate postoperative period is a key factor for pain management. However, this evaluation may be difficult in some circumstances. The pupillary dilatation reflex (PDR) has been successfully used to assess the analgesic component of a balanced anesthetic regimen. We hypothesized that PDR could be a reliable index of pain intensity and could guide morphine administration in the immediate postoperative period.

Methods

One hundred patients scheduled to undergo general surgery were included in this prospective observational study. Pain intensity was assessed by using a simple five-item verbal rating scale (VRS). After patients awoke from general anesthesia, those experiencing mild or more severe pain (VRS more than 1) received intravenous morphine titration. Before and after intravenous morphine titration, the PDR induced by a standardized noxious stimulus was measured with a portable pupillometer. A receiver-operating curve was built to estimate the accuracy of PDR in objectively detecting patients requiring morphine titration. Results are given as median (95% CI).

Results

On the initial evaluation, a correlation was found between VRS and PDR (ρ = 0.88 [0.83-0.92], P < 0.0001). In the 39 patients that had a VRS more than 1, PDR before and after morphine titration was respectively 35% (31-43) versus 12% (10-14); P < 0.0001. The PDR threshold value corresponding to the highest accuracy to have VRS more than 1 was 23%, with 91% and 94% sensitivity and specificity, respectively.

Conclusion

In the immediate postoperative period, the PDR is significantly correlated with the VRS. The pupillometer could be a valuable tool to guide morphine administration in the immediate postoperative period.
A review of protein adsorption on bioceramics
Authors: Wang Kefeng , Zhou Changchun , Hong Youliang , Zhang Xingdong
Published: March 2012

Bioceramics, because of its excellent biocompatible and mechanical properties, has always been considered as the most promising materials for hard tissue repair. It is well know that an appropriate cellular response to bioceramics surfaces is essential for tissue regeneration and integration. As the
in vivo
implants, the implanted bioceramics are immediately coated with proteins from blood and body fluids, and it is through this coated layer that cells sense and respond to foreign implants. Hence, the adsorption of proteins is critical within the sequence of biological activities. However, the biological mechanisms of the interactions of bioceramics and proteins are still not well understood. In this review, we will recapitulate the recent studies on the bioceramic–protein interactions.