bluuebunny/crossref_metadata_2025 huggingface dataset:
Nanoscale Deformation Analysis With High-Resolution Transmission Electron Microscopy and Digital Image Correlation
Authors: Wang Xueju , Pan Zhipeng , Fan Feifei , Wang Jiangwei , Liu Yang , Mao Scott X. , Zhu Ting , Xia Shuman
Published: August 2015

We present an application of the digital image correlation (DIC) method to high-resolution transmission electron microscopy (HRTEM) images for nanoscale deformation analysis. The combination of DIC and HRTEM offers both the ultrahigh spatial resolution and high displacement detection sensitivity that are not possible with other microscope-based DIC techniques. We demonstrate the accuracy and utility of the HRTEM-DIC technique through displacement and strain analysis on amorphous silicon. Two types of error sources resulting from the transmission electron microscopy (TEM) image noise and electromagnetic-lens distortions are quantitatively investigated via rigid-body translation experiments. The local and global DIC approaches are applied for the analysis of diffusion- and reaction-induced deformation fields in electrochemically lithiated amorphous silicon. The DIC technique coupled with HRTEM provides a new avenue for the deformation analysis of materials at the nanometer length scales.
Time-Dependent System Reliability Analysis Using Random Field Discretization
Authors: Hu Zhen , Mahadevan Sankaran
Published: August 2015

This paper proposes a novel and efficient methodology for time-dependent system reliability analysis of systems with multiple limit-state functions of random variables, stochastic processes, and time. Since there are correlations and variations between components and over time, the overall system is formulated as a random field with two dimensions: component index and time. To overcome the difficulties in modeling the two-dimensional random field, an equivalent Gaussian random field is constructed based on the probability equivalency between the two random fields. The first-order reliability method (FORM) is employed to obtain important features of the equivalent random field. By generating samples from the equivalent random field, the time-dependent system reliability is estimated from Boolean functions defined according to the system topology. Using one system reliability analysis, the proposed method can get not only the entire time-dependent system probability of failure curve up to a time interval of interest but also two other important outputs, namely, the time-dependent probability of failure of individual components and dominant failure sequences. Three examples featuring series, parallel, and combined systems are used to demonstrate the effectiveness of the proposed method.
Effect of Pad Flexibility on the Performance of Tilting Pad Journal Bearings—Benchmarking a Predictive Model
Authors: Andrés Luis San , Li Yingkun
Published: August 2015

Tilting pad journal bearings (TPJBs) supporting high-performance turbomachinery rotors have undergone steady design improvements to satisfy ever stringent operating conditions that include large specific loads, due to smaller footprints, and high surface speeds that promote flow turbulence and hence larger drag power losses. Simultaneously, predictive models continuously evolve to include minute details on bearing geometry, pads and pivots' configurations, oil delivery systems, etc. In general, predicted TPJB rotordynamic force coefficients correlate well with experimental data for operation with small to moderately large unit loads (1.7 MPa). Experiments also demonstrate bearing dynamic stiffnesses are frequency dependent, best fitted with a stiffness-mass like model whereas damping coefficients are adequately represented as of viscous type. However, for operation with large specific loads (>1.7 MPa), poor correlation of predictions to measured force coefficients is common. Recently, an experimental effort (Gaines, J., 2014, “Examining the Impact of Pad Flexibility on the Rotordynamic Coefficients of Rocker-Pivot-Pad Tiling-Pad Journal Bearings,” M.S. thesis, Mechanical Engineering, Texas A&M University, College Station, TX) produced test data for three TPJB sets, each having three pads of unequal thickness, to quantify the effect of pad flexibility on the bearings' force coefficients, in particular damping, over a range of load and rotational speed conditions. This paper introduces a fluid film flow model accounting for both pivot and pad flexibility to predict the bearing journal eccentricity, drag power loss, lubricant temperature rise, and force coefficients of typical TPJBs. A finite element (FE) pad structural model including the Babbitt layer is coupled to the thin film flow model to determine the mechanical deformation of the pad surface. Predictions correlate favorably with test data, also demonstrating that pad flexibility produces a reduction of up to 34% in damping for the bearing with the thinnest pads relative to that with the thickest pads. A parametric study follows to quantify the influence of pad thickness on the rotordynamic force coefficients of a sample TPJB with three pads of increasing preload, r¯p  = 0, 0.25 (baseline) and 0.5. The bearing pads are either rigid or flexible by varying their thickness. For design considerations, dimensionless static and dynamic characteristics of the bearings are presented versus the Sommerfeld number (S). Pad flexibility shows a more pronounced effect on the journal eccentricity and the force coefficients of a TPJB with null pad preload than for the bearings with larger pad preloads (0.25 and 0.5), in particular for operation with a small load or at a high surface speed (S > 0.8).
Unsteady Wet Steam Flow Field Measurements in the Last Stage of Low Pressure Steam Turbine
Authors: Bosdas Ilias , Mansour Michel , Kalfas Anestis I. , Abhari Reza S. , Senoo Shigeki
Published: August 2015

Modern steam turbines need to operate efficiently and safely over a wide range of operating conditions. This paper presents a unique unprecedented set of time-resolved steam flowfield measurements from the exit of the last two stages of a low pressure (LP) steam turbine under various volumetric massflow conditions. The measurements were performed in the steam turbine test facility in Hitachi city in Japan. A newly developed fast response probe equipped with a heated tip to operate in wet steam flows was used. The probe tip is heated through an active control system using a miniature high-power cartridge heater developed in-house. Three different operating points (OPs), including two reduced massflow conditions, are compared and a detailed analysis of the unsteady flow structures under various blade loads and wetness mass fractions is presented. The measurements show that at the exit of the second to last stage the flow field is highly three dimensional. The measurements also show that the secondary flow structures at the tip region (shroud leakage and tip passage vortices) are the predominant sources of unsteadiness at 85% span. The high massflow operating condition exhibits the highest level of periodical total pressure fluctuation compared to the reduced massflow conditions at the inlet of the last stage. In contrast at the exit of the last stage, the reduced massflow operating condition exhibits the largest aerodynamic losses near the tip. This is due to the onset of the ventilation process at the exit of the LP steam turbine. This phenomenon results in three times larger levels of relative total pressure unsteadiness at 93% span, compared to the high massflow condition. This implies that at low volumetric flow conditions the blades will be subjected to higher dynamic load fluctuations at the tip region.
Charging suppression in focused-ion beam fabrication of visible subwavelength dielectric grating reflector using electron conducting polymer
Authors: Alias Mohd Sharizal , Liao Hsien-Yu , Ng Tien Khee , Ooi Boon Siew
Published: August 2015

Nanoscale periodic patterning on insulating materials using focused-ion beam (FIB) is challenging because of charging effect, which causes pattern distortion and resolution degradation. In this paper, the authors used a charging suppression scheme using electron conducting polymer for the implementation of FIB patterned dielectric subwavelength grating (SWG) reflector. Prior to the FIB patterning, the authors numerically designed the optimal structure and the fabrication tolerance for all grating parameters (period, grating thickness, fill-factor, and low refractive index layer thickness) using the rigorous-coupled wave analysis computation. Then, the authors performed the FIB patterning on the dielectric SWG reflector spin-coated with electron conducting polymer for the anticharging purpose. They also performed similar patterning using thin conductive film anticharging scheme (30 nm Cr coating) for comparison. Their results show that the electron conducting polymer anticharging scheme effectively suppressing the charging effect during the FIB patterning of dielectric SWG reflector. The fabricated grating exhibited nanoscale precision, high uniformity and contrast, constant patterning, and complied with fabrication tolerance for all grating parameters across the entire patterned area. Utilization of electron conducting polymer leads to a simpler anticharging scheme with high precision and uniformity for FIB patterning on insulator materials.
Fully iterative scatter corrected digital breast tomosynthesis using GPU‐based fast Monte Carlo simulation and composition ratio update
Authors: Kim Kyungsang , Lee Taewon , Seong Younghun , Lee Jongha , Jang Kwang Eun , Choi Jaegu , Choi Young Wook , Kim Hak Hee , Shin Hee Jung , Cha Joo Hee , Cho Seungryong , Ye Jong Chul
Published: August 2015

Purpose:

In digital breast tomosynthesis (DBT), scatter correction is highly desirable, as it improves image quality at low doses. Because the DBT detector panel is typically stationary during the source rotation, antiscatter grids are not generally compatible with DBT; thus, a software‐based scatter correction is required. This work proposes a fully iterative scatter correction method that uses a novel fast Monte Carlo simulation (MCS) with a tissue‐composition ratio estimation technique for DBT imaging.

Methods:

To apply MCS to scatter estimation, the material composition in each voxel should be known. To overcome the lack of prior accurate knowledge of tissue composition for DBT, a tissue‐composition ratio is estimated based on the observation that the breast tissues are principally composed of adipose and glandular tissues. Using this approximation, the composition ratio can be estimated from the reconstructed attenuation coefficients, and the scatter distribution can then be estimated by MCS using the composition ratio. The scatter estimation and image reconstruction procedures can be performed iteratively until an acceptable accuracy is achieved. For practical use, (i) the authors have implemented a fast MCS using a graphics processing unit (GPU), (ii) the MCS is simplified to transport only x‐rays in the energy range of 10–50 keV, modeling Rayleigh and Compton scattering and the photoelectric effect using the tissue‐composition ratio of adipose and glandular tissues, and (iii) downsampling is used because the scatter distribution varies rather smoothly.

Results:

The authors have demonstrated that the proposed method can accurately estimate the scatter distribution, and that the contrast‐to‐noise ratio of the final reconstructed image is significantly improved. The authors validated the performance of the MCS by changing the tissue thickness, composition ratio, and x‐ray energy. The authors confirmed that the tissue‐composition ratio estimation was quite accurate under a variety of conditions. Our GPU‐based fast MCS implementation took approximately 3 s to generate each angular projection for a 6 cm thick breast, which is believed to make this process acceptable for clinical applications. In addition, the clinical preferences of three radiologists were evaluated; the preference for the proposed method compared to the preference for the convolution‐based method was statistically meaningful (p < 0.05, McNemar test).

Conclusions:

The proposed fully iterative scatter correction method and the GPU‐based fast MCS using tissue‐composition ratio estimation successfully improved the image quality within a reasonable computational time, which may potentially increase the clinical utility of DBT.
Measuring retinal blood flow in rats using Doppler optical coherence tomography without knowing eyeball axial length
Authors: Liu Wenzhong , Yi Ji , Chen Siyu , Jiao Shuliang , Zhang Hao F.
Published: August 2015

Purpose:

Doppler optical coherence tomography (OCT) is widely used for measuring retinal blood flow. Existing Doppler OCT methods require the eyeball axial length, in which empirical values are usually used. However, variations in the axial length can create a bias unaccounted for in the retinal blood flow measurement. The authors plan to develop a Doppler OCT method that can measure the total retinal blood flow rate without requiring the eyeball axial length.

Methods:

The authors measured the retinal blood flow rate using a dual‐ring scanning protocol. The small and large scanning rings entered the eye at different incident angles (small ring: 4°; large ring: 6°), focused on different locations on the retina, and detected the projected velocities/phase shifts along the probing beams. The authors calculated the ratio of the projected velocities between the two rings, and then used this ratio to estimate absolute flow velocity. The authors tested this method in both Intralipid phantoms and in vivo rats.

Results:

In the Intralipid flow phantom experiments, the preset and measured flow rates were consistent with the coefficient of determination as 0.97. Linear fitting between preset and measured flow rates determined the fitting slope as 1.07 and the intercept as −0.28. In in vivo rat experiments, the measured average total retinal blood flow was 7.02 ± 0.31μl/min among four wild‐type rats. The authors’ measured flow rates were consistent with results in the literature.

Conclusions:

By using a dual‐ring scanning protocol with carefully controlled incident angle difference between the two scanning rings in Doppler OCT, the authors demonstrated that it is feasible to measure the absolute retinal blood flow without knowing the eyeball axial length.
Semantic processing of unattended speech in dichotic listening
Authors: Aydelott Jennifer , Jamaluddin Zahra , Nixon Pearce Stefanie
Published: August 2015

This study investigated whether unattended speech is processed at a semantic level in dichotic listening using a semantic priming paradigm. A lexical decision task was administered in which target words were presented in the attended auditory channel, preceded by two prime words presented simultaneously in the attended and unattended channels, respectively. Both attended and unattended primes were either semantically related or unrelated to the attended targets. Attended prime–target pairs were presented in isolation, whereas unattended primes were presented in the context of a series of rapidly presented words. The fundamental frequency of the attended stimuli was increased by 40 Hz relative to the unattended stimuli, and the unattended stimuli were attenuated by 12 dB [+12 dB signal-to-noise ratio (SNR)] or presented at the same intensity level as the attended stimuli (0 dB SNR). The results revealed robust semantic priming of attended targets by attended primes at both the +12 and 0 dB SNRs. However, semantic priming by unattended primes emerged only at the 0 dB SNR. These findings suggest that the semantic processing of unattended speech in dichotic listening depends critically on the relative intensities of the attended and competing signals.
T
H
2 and T
H
17 inflammatory pathways are reciprocally regulated in asthma
Authors: Choy David F. , Hart Kevin M. , Borthwick Lee A. , Shikotra Aarti , Nagarkar Deepti R. , Siddiqui Salman , Jia Guiquan , Ohri Chandra M. , Doran Emma , Vannella Kevin M. , Butler Claire A. , Hargadon Beverley , Sciurba Joshua C. , Gieseck Richard L. , Thompson Robert W. , White Sandra , Abbas Alexander R. , Jackman Janet , Wu Lawren C. , Egen Jackson G. , Heaney Liam G. , Ramalingam Thirumalai R. , Arron Joseph R. , Wynn Thomas A. , Bradding Peter
Published: August 2015

Concurrent blockade of IL-13 and IL-17A may improve control of asthma.
High-throughput pairing of T cell receptor α and β sequences
Authors: Howie Bryan , Sherwood Anna M. , Berkebile Ashley D. , Berka Jan , Emerson Ryan O. , Williamson David W. , Kirsch Ilan , Vignali Marissa , Rieder Mark J. , Carlson Christopher S. , Robins Harlan S.
Published: August 2015

T cell receptor α and β sequences can be accurately paired from hundreds of thousands of T cell clones in parallel.
Bile acids go up to BAT
Authors: Alvarez Jessica A.
Published: August 2015

Bile acids activate brown adipose tissue in humans.
Unearthing archival tumor RNA
Authors: Behjati Sam
Published: August 2015

New method for sequencing poor-quality RNA–derived formalin-fixed paraffin-embedded tissue should facilitate studies of tumor RNA.
Cells choose the path less potholed
Authors: Wong Ian Y.
Published: August 2015

Dense arrays of nanoholes deter cell adhesion and migration.
The Reemergent 1977 H1N1 Strain and the Gain-of-Function Debate
Authors: Rozo Michelle , Gronvall Gigi Kwik
Published: August 2015

The 1977-1978 influenza epidemic was probably not a natural event, as the genetic sequence of the virus was nearly identical to the sequences of decades-old strains. While there are several hypotheses that could explain its origin, the possibility that the 1977 epidemic resulted from a laboratory accident has recently gained popularity in discussions about the biosafety risks of gain-of-function (GOF) influenza virus research, as an argument for why this research should not be performed. There is now a moratorium in the United States on funding GOF research while the benefits and risks, including the potential for accident, are analyzed. Given the importance of this historical epidemic to ongoing policy debates, we revisit the evidence that the 1977 epidemic was not natural and examine three potential origins: a laboratory accident, a live-vaccine trial escape, or deliberate release as a biological weapon. Based on available evidence, the 1977 strain was indeed too closely matched to decades-old strains to likely be a natural occurrence. While the origin of the outbreak cannot be conclusively determined without additional evidence, there are very plausible alternatives to the laboratory accident hypothesis, diminishing the relevance of the 1977 experience to the modern GOF debate.
An Alternative Terminal Step of the General Secretory Pathway in Staphylococcus aureus
Authors: Craney Arryn , Dix Melissa M. , Adhikary Ramkrishna , Cravatt Benjamin F. , Romesberg Floyd E.
Published: August 2015

Type I signal peptidase (SPase) is essential for viability in wild-type bacteria because the terminal step of the bacterial general secretory pathway requires its proteolytic activity to release proteins from their membrane-bound N-terminal leader sequences after translocation across the cytoplasmic membrane. Here, we identify the
Staphylococcus aureus
operon
ayrRABC
(SA0337 to SA0340) and show that once released from repression by AyrR, the protein products AyrABC together confer resistance to the SPase inhibitor arylomycin M131 by providing an alternate and novel method of releasing translocated proteins. Thus, the derepression of
ayrRABC
allows cells to bypass the essentiality of SPase. We demonstrate that AyrABC functionally complements SPase by mediating the processing of the normally secreted proteins, albeit in some cases with reduced efficiency and either without cleavage or via cleavage at a site N-terminal to the canonical SPase cleavage site. Thus,
ayrRABC
encodes a secretion stress-inducible alternate terminal step of the general secretory pathway.

IMPORTANCE
Addressing proteins for proper localization within or outside a cell in both eukaryotes and prokaryotes is often accomplished with intrinsic signals which mediate membrane translocation and which ultimately must be removed. The canonical enzyme responsible for the removal of translocation signals is bacterial type I signal peptidase (SPase), which functions at the terminal step of the general secretory pathway and is thus essential in wild-type bacteria. Here, we identify a four-gene operon in
S. aureus
that encodes an alternate terminal step of the general secretory pathway and thus makes SPase nonessential. The results have important implications for protein secretion in bacteria and potentially for protein trafficking in prokaryotes and eukaryotes in general.
New Insight into Filamentous Hemagglutinin Secretion Reveals a Role for Full-Length FhaB in
Bordetella
Virulence
Authors: Melvin Jeffrey A. , Scheller Erich V. , Noël Christopher R. , Cotter Peggy A.
Published: August 2015

Bordetella
filamentous hemagglutinin (FHA), a primary component of acellular pertussis vaccines, contributes to virulence, but how it functions mechanistically is unclear. FHA is first synthesized as an ~370-kDa preproprotein called FhaB. Removal of an N-terminal signal peptide and a large C-terminal prodomain (PD) during secretion results in “mature” ~250-kDa FHA, which has been assumed to be the biologically active form of the protein. Deletion of two C-terminal subdomains of FhaB did not affect production of functional FHA, and the mutant strains were indistinguishable from wild-type bacteria for their ability to adhere to the lower respiratory tract and to suppress inflammation in the lungs of mice. However, the mutant strains, which produced altered FhaB molecules, were eliminated from the lower respiratory tract much faster than wild-type
B. bronchiseptica
, suggesting a defect in resistance to early immune-mediated clearance. Our results revealed, unexpectedly, that full-length FhaB plays a critical role in
B. bronchiseptica
persistence in the lower respiratory tract.

IMPORTANCE
The
Bordetella
filamentous hemagglutinin (FHA) is a primary component of the acellular pertussis vaccine and an important virulence factor. FHA is initially produced as a large protein that is processed during secretion to the bacterial surface. As with most processed proteins, the mature form of FHA has been assumed to be the functional form of the protein. However, our results indicate that the full-length form plays an essential role in virulence
in vivo
. Furthermore, we have found that FHA contains intramolecular regulators of processing and that this control of processing is integral to its virulence activities. This report highlights the advantage of studying protein maturation and function simultaneously, as a role for the full-length form of FHA was evident only from
in vivo
infection studies and not from
in vitro
studies on the production or maturation of FHA or even from
in vitro
virulence-associated activity assays.
A rare case of fever of unknown origin: subcutaneous panniculitis-like T-cell lymphoma (SPTCL)
Authors: Ganesh Yadala , Yadala Vivek , Reddy Indukuru Subbarayalu , De Padua Michelle
Published: August 2015

A 26-year-old man presented with high-grade fever, chills, productive cough and episodic abdominal pain of 6 months duration. Physical examination revealed that the patient was febrile and had multiple, ill-defined, tender, indurated, erythematous nodules and plaques over the trunk and thighs. Systemic examination and investigations revealed bilateral exudative pleural effusion with an increased adenosine deaminase (ADA) level. Pulmonary tuberculosis was suspected and the patient was started on a standard four-drug antitubercular regimen. Since his fever persisted, biopsy of the plaque over the trunk was performed, which showed lobular panniculitis with atypical lymphoid cells. Immunohistochemistry showed atypical lymphoid cells, which were CD3 and CD8 positive and CD4 negative. Based on the clinical features, skin biopsy and immunohistochemistry, the diagnosis of subcutaneous panniculitis-like T-cell lymphoma was made. The patient was treated with chemotherapy followed by bone marrow transplantation, and 4-year follow-up showed complete remission of lymphoma.
The influence of neighbourhood-level socioeconomic deprivation on cardiovascular disease mortality in older age: longitudinal multilevel analyses from a cohort of older British men
Authors: Ramsay S E , Morris R W , Whincup P H , Subramanian S V , Papacosta A O , Lennon Lucy T , Wannamethee S G
Published: August 2015

Background

Evidence from longitudinal studies on the influence of neighbourhood socioeconomic factors in older age on cardiovascular disease (CVD) mortality is limited. We aimed to investigate the prospective association of neighbourhood-level deprivation in later life with CVD mortality, and assess the underlying role of established cardiovascular risk factors.

Methods

A socially representative cohort of 3924 men, aged 60–79 years in 1998–2000, from 24 British towns, was followed up until 2012 for CVD mortality. Quintiles of the national Index of Multiple Deprivation (IMD), a composite score of neighbourhood-level factors (including income, employment, education, housing and living environment) were used. Multilevel logistic regression with discrete-time models (stratifying follow-up time into months) were used.

Results

Over 12 years, 1545 deaths occurred, including 580 from CVD. The risk of CVD mortality showed a graded increase from IMD quintile 1 (least deprived) to 5 (most deprived). Compared to quintile 1, the age-adjusted odds of CVD mortality in quintile 5 were 1.71 (95% CI 1.32 to 2.21), and 1.62 (95% CI 1.23 to 2.13) on further adjustment for individual social class, which was attenuated slightly to 1.44 (95% CI 1.09 to 1.89), but remained statistically significant after adjustment for smoking, body mass index, physical activity and use of alcohol. Further adjustment for blood pressure, high-density lipoprotein cholesterol and prevalent diabetes made little difference.

Conclusions

Neighbourhood-level deprivation was associated with an increased risk of CVD mortality in older people independent of individual-level social class and cardiovascular risk factors. The role of other specific neighbourhood-level factors merits further research.
The effects of 8 weeks of motor skill training on cardiorespiratory fitness and endurance performance in children with developmental coordination disorder
Authors: Farhat Faiçal , Masmoudi Kaouthar , Hsairi Ines , Smits-Engelsman Bouwien C.M. , Mchirgui Radhouane , Triki Chahnez , Moalla Wassim
Published: August 2015

Interventions based on everyday motor skills have been developed to be effective in children with developmental coordination disorder (DCD). The purpose of the present study was to examine the effects of motor skill training on exercise tolerance and cardiorespiratory fitness in children with DCD. Children were assigned to 3 groups: an experimental training group comprising 14 children with DCD, a control nontraining group comprising 13 children with DCD, and a control nontraining group comprising 14 typically developed children. All participants were tested twice with an interval of 8-weeks on a cardiopulmonary exercise test, pulmonary function testing, and a 6-min walk test. After the training program the maximal power output was significantly increased for DCD group at anaerobic threshold (p < 0.05) and at peak level (maximal oxygen uptake, p < 0.001). Improvement in power output was more pronounced at the anaerobic threshold (t (13) = −5.21, p < 0.001) than at the maximal intensity (maximal oxygen uptake, t (13) = −3.08, p < 0.01) in the DCD training group. Children with DCD that participated in the training program improved their walking distance (t (13) = −9.08, p < 0.001), had a higher maximum heart rate (t (13) = −3.41, p < 0.01), and reduced perceived exertion (t (13) = 2.75, p < 0.05). The DCD nontraining group and the typically developed group did not change on any of the measures. In conclusion, training delayed reaching the anaerobic threshold and improved aerobic endurance and exercise tolerance in children with DCD.
Preconditioning with peristaltic external pneumatic compression does not acutely improve repeated Wingate performance nor does it alter blood lactate concentrations during passive recovery compared with sham
Authors: Martin Jeffrey S. , Friedenreich Zachary D. , Borges Alexandra R. , Roberts Michael D.
Published: August 2015

Application of dynamic external pneumatic compression (EPC) during recovery from athletic activities has demonstrated favorable effects on flexibility, soreness, swelling, and blood lactate (BLa) concentrations. However, the effects of “preconditioning” with a peristaltic pulse EPC device on subsequent performance and BLa concentrations have not been characterized. Herein, we demonstrate that pretreatment for 30 min with EPC has no effect on subsequent supramaximal exercise performance or BLa concentrations during passive recovery.
Overstory treatment and planting season affect survival of replacement tree species in emerald ash borer threatened Fraxinus nigra forests in Minnesota, USA
Authors: Looney Christopher E. , D’Amato Anthony W. , Palik Brian J. , Slesak Robert A.
Published: August 2015

Fraxinus nigra Marsh. (black ash) wetland forests in northern Minnesota, USA, are threatened by the invasive insect, emerald ash borer (Agrilus planipennis Fairmaire (EAB)). A potential management option is promoting regeneration of tree species that are not EAB hosts to maintain ecosystem functions. Using an operational-scale field experiment, we examined the survival of 12 alternative tree species in response to different canopy treatments. We planted the seedlings in 1.6 ha plots assigned to four replicated canopy treatments: untreated control, group selection (0.04 ha gaps, 20% of stand), black ash girdling to emulate EAB-induced mortality, and clearcut. Fall and spring plantings were used to compare the effects of spring ponding. Control (32.9%), group selection (34.5%), and girdling (33.3%) treatments had comparable overall seedling survival. Survival in the clear-cut treatments was significantly lower (22%). Species selection, overstory treatment, and season of planting together resulted in survival rates ranging from 0.08% to 94.1%. Conifer species had low overall rates of survival (10.7%), whereas some species with native ranges not presently overlapping with northern F. nigra forests, e.g., Quercus bicolor Willd. (75.5%), had high survival rates. If growth is light-limited, group selection may be effective in promoting recruitment and supporting a larger variety of species.
Ameliorative effect of trimetazidine on cisplatin-induced hepatotoxicity in rats
Authors: Ateyya Hayam , Yosef Hala , Nader Manar A.
Published: August 2015

This study was designed to evaluate the protective effects of trimetazidine (TMZ) against cisplatin (CP) induced liver damage in rats. Animals were distributed among 4 groups as follows: control group; TMZ group (20 mg/kg body mass, per oral), which was treated for 10 days; CP group (6 mg/kg, by intraperitoneal injection), which received a single injection; and the CP + TMZ group (20 mg/kg, per oral), which received TMZ 4 days before and 6 days after CP injection. The extent of hepatic damage was studied by assessing biochemical parameters and histopathological evaluation of the extracted liver tissue. The results revealed that liver enzymes were markedly elevated after injection of CP, as evident from significant increases in the serum levels of alanine transaminase (AST), alanine aminotransferase (ALT), gamma glutamyl transferase (γ-GT), and lactate dehydrogenase (LDH), as well as marked changes to the liver architecture, with a significant decrease in serum levels of albumin. There were also marked changes to the antioxidant defense system, as indicated by significant decreases in total antioxidants and hepatic levels of reduced glutathione (GSH) and superoxide dismutase (SOD), together with a significant increase in lipid peroxidation. However, there was a significant increase in the activity of hepatic nuclear factor kappa B (NF-κB) as well as hepatic Bax protein expression. We conclude that TMZ protects against CP-induced liver damage through scavenging free radicals and anti-inflammatory and antiapoptotic effects, as well as through reducing NF-κB activation.
Maternal effect and speciation: maternal effect contributes to the evolution of hybrid inviability betweenDrosophila simulansandDrosophila mauritiana
Authors: Eizadshenass Sogol , Singh Rama S.
Published: August 2015

Haldane’s rule has been the basis of speciation research during the last 30 years. Most studies have focused on the nature of incompatibilities in the hybrid male, but not much attention has been given to the genetic basis of fertility and inviability in hybrid females. Hybridizations between Drosophila simulans and Drosophila mauritiana produce fertile females and sterile males. Here, we re-examined the level of fertility in reciprocal F1 females of these two species and looked for the presence of maternal effects. Our results show that the reciprocal F1 females of D. simulans and D. mauritiana hybridizations are fully fertile and in fact show a significant level of heterosis in the rate of oviposition but display reduced egg hatching in one direction. Reduced egg hatching was observed in the progenies of F1 hybrid females with D. mauritiana as mother, the same cross that showed a stronger negative effect on F1 male fertility. A review of the literature on the hybridizations in Lepidoptera also showed a maternal effect on inviability when reciprocal crosses produced asymmetric results. Our findings point to the importance of maternal effects in the evolution of embryo inviability and thus enhancing the process of speciation through the evolution of hybrid inviability.
Testing the influence of the gravitational redshift on the Casimir effect in space
Authors: de Matos Clovis Jacinto , Tajmar Martin
Published: August 2015

We show that the Casimir effect should be influenced by variations of the gravitational potential. This could be tested with a satellite in a highly elliptic orbit. Still significant technology development is required to achieve a relative accuracy of [Formula: see text] necessary to detect the effect around Earth. That may be obtained in the future based on recent concepts for giant Casimir forces. Such a space mission could evaluate both the laws of gravitation and quantum mechanics and their interaction. A dedicated mission, Gravity-Probe C (GP-C), is proposed.
Testing sterile neutrino extensions of the Standard Model at the Circular Electron Positron Collider
Authors: Antusch Stefan , Fischer Oliver
Published: August 2015

Extending the Standard Model with sterile (“right-handed”) neutrinos is one of the best motivated ways to account for the observed neutrino masses. We discuss the expected sensitivity of the Circular Electron Positron Collider (CEPC) for testing such extensions. An interesting scenario is given by symmetry protected seesaw models, which theoretically allow for sterile neutrino masses around the electroweak scale with up to order one mixings with the active (SM) neutrinos.

When the masses of the sterile neutrinos are well above the electroweak scale, they affect precision data via effective non-unitarity of the leptonic mixing matrix in a model independent way. The expected improvement of the electroweak precision observables from the CEPC may allow to test mixings between active and sterile neutrinos down to [Formula: see text] (using currently discussed CEPC performance parameters).

For sterile neutrinos with masses around the electroweak scale, direct searches are possible. Such tests are given by the search for sterile neutrino decays at the [Formula: see text] pole, by deviations from the SM cross section for four leptons at and beyond the [Formula: see text] threshold, and by Higgs boson production and decays. The expected sensitivities at the CEPC could reach down to mixings as small as [Formula: see text].
A heuristic approach to the quantum measurement problem: How to distinguish particle detectors from ordinary objects
Authors: Merlin R.
Published: August 2015

Elementary particle detectors fall broadly into only two classes: phase-transformation devices, such as the bubble chamber, and charge-transfer devices like the Geiger–Müller tube. Quantum measurements are seen to involve transitions from a long-lived metastable state (e.g., superheated liquid or a gas of atoms between charged capacitor plates) to a thermodynamically stable condition. A detector is then a specially prepared object undergoing a metastable-to-stable transformation that is significantly enhanced by the presence of the measured particle, which behaves, in some sense, as the seed of a process of heterogeneous nucleation. Based on this understanding of the operation of a conventional detector, and using results of orthogonality-catastrophe theory, we argue that, in the thermodynamic limit, the pre-measurement Hamiltonian is not the same as that describing the detector during or after the interaction with a particle and, thus, that superpositions of pointer states (Schrödinger’s cats) are unphysical because their time evolution is ill defined. Examples of particle-induced changes in the Hamiltonian are also given for ordinary systems whose macroscopic parameters are susceptible to radiation damage, but are not modified by the interaction with a single particle.
CALIBRATION OF STOCHASTIC VOLATILITY MODELS VIA SECOND-ORDER APPROXIMATION: THE HESTON CASE
Authors: ALÒS ELISA , DE SANTIAGO RAFAEL , VIVES JOSEP
Published: August 2015

In this paper, we present a new, simple and efficient calibration procedure that uses both the short and long-term behavior of the Heston model in a coherent fashion. Using a suitable Hull and White-type formula, we develop a methodology to obtain an approximation to the implied volatility. Using this approximation, we calibrate the full set of parameters of the Heston model. One of the reasons that makes our calibration for short times to maturity so accurate is that we take into account the term structure for large times to maturity: We may thus say that calibration is not "memoryless," in the sense that the option's behavior far away from maturity does influence calibration when the option gets close to expiration. Our results provide a way to perform a quick calibration of a closed-form approximation to vanilla option prices, which may then be used to price exotic derivatives. The methodology is simple, accurate, fast and it requires a minimal computational effort.
Theory of newforms for Eisenstein series of half-integral weight
Authors: Jagathesan T. , Manickam M.
Published: August 2015

In this paper, we set up the theory of newforms for the space of Eisenstein series of weight [Formula: see text] for [Formula: see text] ([Formula: see text], [Formula: see text]) which is compatible with the theory of newforms for the space of Eisenstein series of weight 2[Formula: see text] and level 2[Formula: see text].
Prescribing the behavior of Weil–Petersson geodesics in the moduli space of Riemann surfaces
Authors: Modami Babak
Published: August 2015

We study Weil–Petersson (WP) geodesics with narrow end invariant and develop techniques to control length-functions and twist parameters along them and prescribe their itinerary in the moduli space of Riemann surfaces. This class of geodesics is rich enough to provide for examples of closed WP geodesics in the thin part of the moduli space, as well as divergent WP geodesic rays with minimal filling ending lamination.

Some ingredients of independent interest are the following: A strength version of Wolpert's Geodesic Limit Theorem proved in Sec. 4. The stability of hierarchy resolution paths between narrow pairs of partial markings or laminations in the pants graph proved in Sec. 5. A kind of symbolic coding for laminations in terms of subsurface coefficients presented in Sec. 7.
Some perturbed Ostrowski type inequalities for functions of bounded variation
Authors: Dragomir S. S.
Published: August 2015

In this paper, some general two parameters perturbed Ostrowski type inequalities for functions of bounded variation are established.
A generalization of the Euler’s totient function
Authors: Tărnăuceanu Marius
Published: August 2015

The main goal of this paper is to provide a group theoretical generalization of the well-known Euler’s totient function. This determines an interesting class of finite groups.
China's War on Smog: Measures and Challenges
Authors: LU Ding , WAN Jing
Published: August 2015

China has taken a series of proactive measures to prevent and control air pollution. The Air Pollution Prevention and Control Action Plan (2013) includes main policy initiatives to improve national and regional air quality. Fiscal reforms are needed to fund clean-air technology and incentivise firms and households to reduce pollution and economise energy use. The War on Smog requires high-level coordination of governments at different levels and various local jurisdictions.
Chongqing under Sun Zhengcai
Authors: ZHAO Litao , QIAN Jiwei
Published: August 2015

Chongqing is the latest and largest municipality directly under the administration of the central government and the only one in China's vast inland regions. Sun Zhengcai, a new Politburo member at the 18th Party Congress, became Chongqing's party secretary in November 2011. The former minister of agriculture and later party secretary of Jilin, Sun has demonstrated a down-to-earth working style. Policy-wise, he continues but refines what Chongqing has been doing, with possible breakthroughs in some areas.
Maritime Piracy and China's Policy Options to Southeast Asian Waters
Authors: CHEN Kai
Published: August 2015

Southeast Asia remains one of the worst-hit regions in maritime piracy; pirates adopt new tactics and anti-piracy security governance presents inefficiencies, particularly sovereignty sensitivity in Southeast Asian waters. This article explores the context-sensitive policy options in the foreseeable future. Private security companies could be an alternative solution to maritime piracy for China and the most critical variable would be the China National Security Council.
The skeleton in the closet: actin cytoskeletal remodeling in β-cell function
Authors: Arous Caroline , Halban Philippe A.
Published: August 2015

Over the last few decades, biomedical research has considered not only the function of single cells but also the importance of the physical environment within a whole tissue, including cell-cell and cell-extracellular matrix interactions. Cytoskeleton organization and focal adhesions are crucial sensors for cells that enable them to rapidly communicate with the physical extracellular environment in response to extracellular stimuli, ensuring proper function and adaptation. The involvement of the microtubular-microfilamentous cytoskeleton in secretion mechanisms was proposed almost 50 years ago, since when the evolution of ever more sensitive and sophisticated methods in microscopy and in cell and molecular biology have led us to become aware of the importance of cytoskeleton remodeling for cell shape regulation and its crucial link with signaling pathways leading to β-cell function. Emerging evidence suggests that dysfunction of cytoskeletal components or extracellular matrix modification influences a number of disorders through potential actin cytoskeleton disruption that could be involved in the initiation of multiple cellular functions. Perturbation of β-cell actin cytoskeleton remodeling could arise secondarily to islet inflammation and fibrosis, possibly accounting in part for impaired β-cell function in type 2 diabetes. This review focuses on the role of actin remodeling in insulin secretion mechanisms and its close relationship with focal adhesions and myosin II.
Proximal arm kinematics affect grip force-load force coordination
Authors: Vermillion Billy C. , Lum Peter S. , Lee Sang Wook
Published: August 2015

During object manipulation, grip force is coordinated with load force, which is primarily determined by object kinematics. Proximal arm kinematics may affect grip force control, as proximal segment motion could affect control of distal hand muscles via biomechanical and/or neural pathways. The aim of this study was to investigate the impact of proximal kinematics on grip force modulation during object manipulation. Fifteen subjects performed three vertical lifting tasks that involved distinct proximal kinematics (elbow/shoulder), but resulted in similar end-point (hand) trajectories. While temporal coordination of grip and load forces remained similar across the tasks, proximal kinematics significantly affected the grip force-to-load force ratio ( P = 0.042), intrinsic finger muscle activation ( P = 0.045), and flexor-extensor ratio ( P < 0.001). Biomechanical coupling between extrinsic hand muscles and the elbow joint cannot fully explain the observed changes, as task-related changes in intrinsic hand muscle activation were greater than in extrinsic hand muscles. Rather, between-task variation in grip force (highest during task 3) appears to contrast to that in shoulder joint velocity/acceleration (lowest during task 3). These results suggest that complex neural coupling between the distal and proximal upper extremity musculature may affect grip force control during movements, also indicated by task-related changes in intermuscular coherence of muscle pairs, including intrinsic finger muscles. Furthermore, examination of the fingertip force showed that the human motor system may attempt to reduce variability in task-relevant motor output (grip force-to-load force ratio), while allowing larger fluctuations in output less relevant to task goal (shear force-to-grip force ratio).
Hip proprioceptive feedback influences the control of mediolateral stability during human walking
Authors: Roden-Reynolds Devin C. , Walker Megan H. , Wasserman Camille R. , Dean Jesse C.
Published: August 2015

Active control of the mediolateral location of the feet is an important component of a stable bipedal walking pattern, although the roles of sensory feedback in this process are unclear. In the present experiments, we tested whether hip abductor proprioception influenced the control of mediolateral gait motion. Participants performed a series of quiet standing and treadmill walking trials. In some trials, 80-Hz vibration was applied intermittently over the right gluteus medius (GM) to evoke artificial proprioceptive feedback. During walking, the GM was vibrated during either right leg stance (to elicit a perception that the pelvis was closer mediolaterally to the stance foot) or swing (to elicit a perception that the swing leg was more adducted). Vibration during quiet standing evoked leftward sway in most participants (13 of 16), as expected from its predicted perceptual effects. Across the 13 participants sensitive to vibration, stance phase vibration caused the contralateral leg to be placed significantly closer to the midline (by ∼2 mm) at the end of the ongoing step. In contrast, swing phase vibration caused the vibrated leg to be placed significantly farther mediolaterally from the midline (by ∼2 mm), whereas the pelvis was held closer to the stance foot (by ∼1 mm). The estimated mediolateral margin of stability was thus decreased by stance phase vibration but increased by swing phase vibration. Although the observed effects of vibration were small, they were consistent with humans monitoring hip proprioceptive feedback while walking to maintain stable mediolateral gait motion.