bluuebunny/crossref_metadata_2025 huggingface dataset:
Doping hepta-alanine with tryptophan: A theoretical study of its effect on the electrical conductance of peptide-based single-molecule junctions
Authors: Schosser Werner M. , Zotti Linda A. , Cuevas Juan Carlos , Pauly Fabian
Published: May 2019

Motivated by a recent experiment [C. Guo et al., Proc. Natl. Acad. Sci. U. S. A. 113, 10785 (2016)], we carry out a theoretical study of electron transport through peptide-based single-molecule junctions. We analyze the pristine hepta-alanine and its functionalizations with a single tryptophan unit, which is placed in three different locations along the backbone. Contrary to expectations from the experiment on self-assembled monolayers, we find that insertion of tryptophan does not raise the electrical conductance and that the resulting peptides instead remain insulating in the framework of a coherent transport picture. The poor performance of these molecules as conductors can be ascribed to the strongly off-resonant transport and low electrode-molecule coupling of the frontier orbitals. Although the introduction of tryptophan increases the energy of the highest occupied molecular orbital (HOMO) of the peptides in the gas phase, the new HOMO states are localized on the tryptophan unit and therefore essentially do not contribute to coherent charge transport.
Separable resolution-of-the-identity with all-electron Gaussian bases: Application to cubic-scaling RPA
Authors: Duchemin Ivan , Blase Xavier
Published: May 2019

We explore a separable resolution-of-the-identity (RI) formalism built on quadratures over limited sets of real-space points designed for all-electron calculations. Our implementation preserves, in particular, the use of common atomic orbitals and their related auxiliary basis sets. The setup of the present density fitting scheme, i.e., the calculation of the system specific quadrature weights, scales cubically with respect to the system size. Extensive accuracy tests are presented for the Fock exchange and MP2 correlation energies. We finally demonstrate random phase approximation (RPA) correlation energy calculations with a scaling that is cubic in terms of operations, quadratic in memory, with a small crossover with respect to our standard RI-RPA implementation.
Generalized oscillator strengths of carbon disulfide calculated by multireference configuration interaction
Authors: Oliveira A. P. , Jalbert Ginette , Rocha A. B.
Published: May 2019

Transition energies and generalized oscillator strengths (GOSs) for transitions up to 6.3 eV of carbon disulfide were calculated at the multireference configuration interaction level. It is shown that the consideration of the vibronic coupling mechanism is essential to establish not only a quantitative but also a qualitative profile of the GOS, as a function of the momentum transferred, for the dipole forbidden transitions (Σg+1→1Σu− and Σg+1→1Δu). For the dipole allowed Σg+→Σu+ transition, the calculated GOS is in good agreement with the available experimental data.
A polycrystalline-silicon dual-gate MOSFET-based 1T-DRAM using grain boundary-induced variable resistance
Authors: Yoon Young Jun , Seo Jae Hwa , Cho Seongjae , Lee Jong-Ho , Kang In Man
Published: May 2019

A polycrystalline-silicon (poly-Si) dual-gate MOSFET-based one-transistor dynamic random-access memory (1T-DRAM) cell was developed using grain boundary (GB)-induced barrier effects. The program/erase operation of the 1T-DRAM is performed by trapping/detrapping charges in GB traps. The trapped charges cause variations in the grain energy barrier of the storage region, which forms the sensing margin of the 1T-DRAM. The proposed cell achieved a high sensing margin of 4.45 μA/μm and a long retention time (>100 ms) at a high temperature of 373 K (100 °C).
Microscopic origin of the high piezoelectric response of Sm-doped BiFeO3 near the morphotropic phase boundary
Authors: Liao Zhenyu , Sun Wei , Zhang Qiqi , Li Jing-Feng , Zhu Jing
Published: May 2019

Rare-earth element-doped BiFeO3 has an ultrahigh piezoelectric response near the morphotropic phase boundary (MPB), making it a promising substitute for toxic lead-based piezoelectric materials. As a ferroelectric–antiferroelectric MPB, its microscopic mechanism, especially the contribution of each phase to the piezoelectric performance, is still unclear. In this work, the origin of the giant piezoelectric response of Sm-doped BiFeO3 thin films was studied by combining nanoscale in situ electric field experiments and atomic-resolution electron microscopy. Two independent reversible phase transitions were found under an external electric field: a phase transition between the polar and nonpolar phases and a phase transition between the polar and antipolar phases. Calculations indicated that the enhancement of the piezoelectric response at the MPB originated from these two reversible phase transitions, which were realized via the nucleation of the nanoscale new phase and the motion of the phase boundary under the external electric field. The above results provide deeper insight into the mechanism of the electromechanical response near the ferroelectric–antiferroelectric MPB in rare-earth element-doped BiFeO3 thin films.
Metastable ω′-Fe3C carbide formed during ω-Fe3C particle coarsening in binary Fe-C alloys
Authors: Ping D. H. , Xiang H. P. , Liu X. , Ji X. , Li S. J. , Lu X.
Published: May 2019

Nanosized (∼2 nm) ω-Fe3C particles with hexagonal structures have been observed only at body-centered cubic (BCC) {112}〈111〉-type twinning boundaries in twinned Fe-C martensite of the Fe-C alloy system. However, these ultrafine ω-Fe3C particles never grow large enough to be observed easily. The present structural modeling and electron diffraction calculations reveal that the formation of the new carbide (ω′-Fe3C) during coarsening of the ultrafine ω-Fe3C particles is inevitable. Coarsening or aggregation of fine ω-Fe3C particles may result in a phase transition due to the arrangement of interstitial carbon atoms. A ω-Fe3C → ω′-Fe3C transition was analyzed at the atomic scale. The ω′-Fe3C phase can exhibit an orthorhombic structure with lattice parameters aω′ = 4.033 Å, bω′ = 2.470 Å, and cω′ = 6.986 Å based on aω′ = aω, bω′ = cω, and cω′=3aω for abcc or aα-Fe = 2.852 Å (aω=2abcc, cω=3/2abcc). The simulated ω′-Fe3C electron diffraction patterns were experimentally confirmed. The ω-Fe3C → ω′-Fe3C transition can explain why the ω-Fe3C phase never becomes larger than several nanometers in carbon steel.
Effect of damage incubation in the laser grooving of sapphire
Authors: Sakurai Haruyuki , He Chao , Konishi Kuniaki , Tamaru Hiroharu , Yumoto Junji , Kuwata-Gonokami Makoto , Gillner Arnold
Published: May 2019

With the advancement of ultrashort pulsed-laser processing technologies, greater control of processing conditions has come into demand. A factor which particularly complicates ablation situations is “damage incubation,” a phenomenon in which the intrinsic optical properties of the processed material change due to accumulated defects from repeated laser excitation. Damage incubation can induce striking changes in the observed morphology during ablation and should be an important factor governing processing results. However, only a few studies have incorporated these effects into multiple-pulse ablation models due to its complexity. Here, in order to quantify the effects of damage incubation in a practical processing setting, we study ablation morphologies of shallow grooves formed on the surface of sapphire (α-Al2O3) with varying laser pulse number and energy in a purpose-made experiment. We observe clear evidence of incubation-induced changes in ablation phase and nonlinear dependence of depth on the incident total energy density. To understand the results, we create a simple empirical model for material energy absorption by characterizing interpulse absorption changes and analytically derive solutions for two limiting cases in which the material has either a very low (quasistatic absorption) or very high (accumulative absorption) damage incubation characteristic. By following the energy absorption characteristics predicted by the latter model, we were able to derive universal relations between ablated depth and incident energy density for sapphire. This work serves to highlight the effects of damage incubation on multiple-pulse ablation situations and provides a simple and practical method to predict such morphological characteristics of an arbitrary material.
Epitaxial stabilization of Sr3Ir2O7 thin films
Authors: Yang Junyi , Hao Lin , Nanney Peyton , Noordhoek Kyle , Meyers Derek , Horak Lukas , Sanchez Joshua , Chu Jiun-Haw , Nelson Christie , Dean Mark. P. M. , Liu Jian
Published: May 2019

Ruddlesden-Popper type Srn+1IrnO3n+1 compounds are a major focus of condensed matter physics, where the subtle balance between electron-electron correlation, spin–orbit interaction, and crystal field effect brings a host of emergent phenomena. While it is understandable that a canted antiferromagnetic insulating state with an easy-plane anisotropy is developed in Sr2IrO4 as the two-dimensional limit of the series, it is intriguing that bilayer Sr3Ir2O7, with slightly higher effective dimensionality, stabilizes c-axis collinear antiferromagnetism. This also renders Sr3Ir2O7 a unique playground to study exotic physics near a critical spin transition point. However, the epitaxial growth of Sr3Ir2O7 is still a challenging task because of the narrow growth window. In our research, we have studied the thermodynamic process during the synthesis of Sr3Ir2O7 thin films. We expanded the synthesis window by mapping out the relationship between the thin film crystal structure and the gas pressure. Our work thus provides a more accessible avenue to stabilize metastable materials.
Interfacial properties of binary Lennard-Jones mixtures by molecular simulation and density gradient theory
Authors: Stephan Simon , Langenbach Kai , Hasse Hans
Published: May 2019

A systematic study of interfacial properties of binary mixtures of simple fluids was carried out by molecular dynamics (MD) simulation and density gradient theory (DGT). The fluids are described by the Lennard-Jones truncated and shifted (LJTS) potential with truncation radius of 2.5 diameters. The following interfacial properties were studied: surface tension, relative adsorption, enrichment, and interfacial thickness. A recently developed equation of state for the LJTS fluid, the Perturbed Lennard-Jones truncated and shifted equation of state (PeTS EOS) was used as the basis for DGT. Six binary mixtures (components 1 + 2) were studied at a constant temperature, which was chosen such that the high-boiling component 1 is subcritical, while the low-boiling component 2 is either subcritical or supercritical. Furthermore, a parameter ξ in the combination rule for the unlike dispersive interaction was varied such that the resulting mixtures showed three types of behavior: high-boiling azeotrope, ideal, and low-boiling azeotrope. The parameters of the LJTS potential, including ξ, were also used in the PeTS EOS without any adjustment. Despite this simple approach, excellent agreement between the results of the PeTS EOS and the MD results for the phase equilibrium and the interfacial properties is observed. Enrichment at the interface is only found for the low-boiling component 2. The enrichment increases with decreasing concentration of component 2 and is favored by high boiling point differences of the pure components 1 and 2 and positive deviations from Raoult’s law for the mixture 1 + 2.
Investigation of role of the discharge tube in pulse modulated surface-wave argon plasma column at atmospheric pressure by optical emission spectroscopy
Authors: Chen Chuan-Jie , Li Shou-Zhe , Wu Yue , Zhang Jialiang
Published: May 2019

The axial profiles of the pulse modulated atmospheric pressure surface-wave argon plasma confined in discharge tubes of different diameters are measured by means of optical emission spectroscopy with respect to the emission intensity, gas temperature, and electron density and temperature. Then, the role of the discharge tube is investigated with respect to its diameter. Furthermore, a simplified theoretical model for high collision frequency is proposed for analysis of the experimental results of electron density obtained by the Stark broadening technique, achieving a good agreement between them for discharge tubes of different diameters.
Spatio-temporal behavior of density jumps and the effect of neutral depletion in high-density helicon plasma
Authors: Isayama S. , Shinohara S. , Hada T. , Chen S. H.
Published: May 2019

Abrupt jumps in the density of helicon discharge have been observed following continuous variation of parameters such as the external magnetic field and the radio frequency (RF) input power. In this study, we show the spatio-temporal behavior of such density jumps and the mode transition in a helicon plasma. It is found that the density jump process is characterized by two temporal phases with the contribution of higher axial modes, changing the antenna current (and thus the RF power). We also investigated the effect of the neutral depletion on the local plasma equilibrium. The temporal fluctuation of the plasma density caused by the neutral depletion was observed.
The EXP pair-potential system. III. Thermodynamic phase diagram
Authors: Pedersen Ulf R. , Bacher Andreas K. , Schrøder Thomas B. , Dyre Jeppe C.
Published: May 2019

This paper determines the thermodynamic phase diagram of the EXP system of particles interacting by the purely repulsive exponential pair potential. The solid phase is face-centered cubic (fcc) at low densities and pressures. At higher densities and pressures, the solid phase is body-centered cubic (bcc) with a re-entrant liquid phase at the highest pressures simulated. The investigation first identifies the phase diagram at zero temperature at which the following four crystal structures are considered: fcc, bcc, hexagonal close packed, and cubic diamond. There is a T = 0 phase transition at pressure 2.651 × 10−3 with the thermodynamically stable structure being fcc below and bcc above this pressure. The densities of the two crystal structures at the phase transition are 1.7469 × 10−2 (fcc) and 1.7471 × 10−2 (bcc). At finite temperatures, the fcc–bcc, fcc-liquid, and bcc-liquid coexistence lines are determined by numerical integration of the Clausius–Clapeyron equation and validated by interface-pinning simulations at selected state points. The bcc-fcc phase transition is a weak first-order transition. The liquid-fcc–bcc triple point, which is determined by the interface-pinning method, has temperature 5.9 × 10−5 and pressure 2.5 × 10−6; the triple-point densities are 1.556 × 10−3 (liquid), 1.583 × 10−3 (bcc), and 1.587 × 10−3 (fcc).
Computational spectroscopy of trehalose, sucrose, maltose, and glucose: A comprehensive study of TDSS, NQR, NOE, and DRS
Authors: Heid Esther , Honegger Philipp , Braun Daniel , Szabadi András , Stankovic Toda , Steinhauser Othmar , Schröder Christian
Published: May 2019

The bioprotective nature of monosaccharides and disaccharides is often attributed to their ability to slow down the dynamics of adjacent water molecules. Indeed, solvation dynamics close to sugars is indisputably retarded compared to bulk water. However, further research is needed on the qualitative and quantitative differences between the water dynamics around different saccharides. Current studies on this topic disagree on whether the disaccharide trehalose retards water to a larger extent than other isomers. Based on molecular dynamics simulation of the time-dependent Stokes shift of a chromophore close to the saccharides trehalose, sucrose, maltose, and glucose, this study reports a slightly stronger retardation of trehalose compared to other sugars at room temperature and below. Calculation and analysis of the intermolecular nuclear Overhauser effect, nuclear quadrupole relaxation, dielectric relaxation spectroscopy, and first shell residence times at room temperature yield further insights into the hydration dynamics of different sugars and confirm that trehalose slows down water dynamics to a slightly larger extent than other sugars. Since the calculated observables span a wide range of timescales relevant to intermolecular nuclear motion, and correspond to different kinds of motions, this study allows for a comprehensive view on sugar hydration dynamics.
Evolution of atomic structures of SnN, SnN−, and SnNCl− clusters (N = 4–20): Insight from ab initio calculations
Authors: Wu Di , Du Qiuying , Wu Xue , Shi Ruili , Sai Linwei , Liang Xiaoqing , Huang Xiaoming , Zhao Jijun
Published: May 2019

An unbiased global search was employed to explore the low-energy structures of SnN, SnN−, and SnNCl− clusters with N = 4–20 atoms based on the genetic algorithm combined with density functional theory calculations. Some unprecedented low-energy isomers are reported for SnN and SnNCl− clusters. The theoretical electronic properties such as binding energy per atom, ionization potential, adiabatic detachment energy, and vertical detachment energy compare well with the experimental data. Based on the equilibrium structures, the simulated photoelectron spectra are in good agreement with the experimental data in the range of N = 4–20. With addition of a Cl atom on the SnN− cluster, which causes almost no rearrangement on the structural framework, the first peaks in all original photoelectron spectra of SnN− clusters disappear and other peaks nearly retain the original feature at most sizes.
New review highlights correlative microscopy methodology that combines imaging modalities
Authors: Liebendorfer Adam
Published: May 2019

Combining transmission electron microscopy with secondary ion mass spectrometry can expand the tools available for chemically characterizing materials on the nanoscale.
FAM64A positively regulates STAT3 activity to promote Th17 differentiation and colitis-associated carcinogenesis
Authors: Xu Zhi-Sheng , Zhang Hong-Xia , Li Wei-Wei , Ran Yong , Liu Tian-Tian , Xiong Mei-Guang , Li Qing-Lan , Wang Su-Yun , Wu Min , Shu Hong-Bing , Xia Huimin , Wang Yan-Yi
Published: May 2019

Significance

The transcription factor STAT3 plays pivotal roles in various physiological processes, including differentiation of Th cells. Its deregulation results in serious diseases, including inflammatory diseases and cancer. Understanding how STAT3 activity is regulated is important for deciphering the pathogenesis of such diseases. In this study, we identified a protein called FAM64A, which promotes STAT3 activity through modulating the DNA-binding activity of STAT3. Consequently, FAM64A also promotes Th17 differentiation and development of colitis and colitis-associated cancer. This study reveals a previously unreported function of FAM64A in the regulation of inflammation and tumorigenesis and provides a potential therapeutic target for inflammatory diseases and cancer.
Second-order induction in prediction problems
Authors: Argenziano Rossella , Gilboa Itzhak
Published: May 2019

Significance

How do people generate beliefs about economic, political, and social events? A natural formula for the predicted value of a variable is its weighted average value in the past, where past values are given a higher weight if they were observed in circumstances more similar to the current ones. Agents learn from the data the best way to assess the similarity of past cases to the present one. The basic formula and this learning process appeared both in statistics and in psychology and they thus make sense for modeling economic agents. We study this process and identify circumstances under which agents are likely to agree on predictions and conditions under which disagreement over predictions may be reasonably expected.
Endothelial NMDA receptors mediate activity-dependent brain hemodynamic responses in mice
Authors: Hogan-Cann Adam D. , Lu Ping , Anderson Christopher M.
Published: May 2019

Dynamic coupling of blood supply with energy demand is a natural brain property that requires signaling between synapses and endothelial cells. Our previous work showed that cortical arteriole lumen diameter is regulated by
N
-methyl-
d
-aspartate receptors (NMDARs) expressed by brain endothelial cells. The purpose of this study was to determine whether endothelial NMDARs (eNMDARs) regulate functional hyperemia in vivo. In response to whisker stimulation, regional cerebral blood flow (rCBF) and hemodynamic responses were assessed in barrel cortex of awake wild-type or eNMDAR loss-of-function mice using two-photon microscopy. Hyperemic enhancement of rCBF and vasodilation throughout the vascular network was observed in wild-type mice. eNMDAR loss of function reduced hyperemic responses in rCBF and plasma flux in individual vessels. Discovery of an endothelial receptor that regulates brain hyperemia provides insight into how neuronal activity couples with endothelial cells.
Genomic correlates of clinical outcome in advanced prostate cancer
Authors: Abida Wassim , Cyrta Joanna , Heller Glenn , Prandi Davide , Armenia Joshua , Coleman Ilsa , Cieslik Marcin , Benelli Matteo , Robinson Dan , Van Allen Eliezer M. , Sboner Andrea , Fedrizzi Tarcisio , Mosquera Juan Miguel , Robinson Brian D. , De Sarkar Navonil , Kunju Lakshmi P. , Tomlins Scott , Wu Yi Mi , Nava Rodrigues Daniel , Loda Massimo , Gopalan Anuradha , Reuter Victor E. , Pritchard Colin C. , Mateo Joaquin , Bianchini Diletta , Miranda Susana , Carreira Suzanne , Rescigno Pasquale , Filipenko Julie , Vinson Jacob , Montgomery Robert B. , Beltran Himisha , Heath Elisabeth I. , Scher Howard I. , Kantoff Philip W. , Taplin Mary-Ellen , Schultz Nikolaus , deBono Johann S. , Demichelis Francesca , Nelson Peter S. , Rubin Mark A. , Chinnaiyan Arul M. , Sawyers Charles L.
Published: May 2019

Heterogeneity in the genomic landscape of metastatic prostate cancer has become apparent through several comprehensive profiling efforts, but little is known about the impact of this heterogeneity on clinical outcome. Here, we report comprehensive genomic and transcriptomic analysis of 429 patients with metastatic castration-resistant prostate cancer (mCRPC) linked with longitudinal clinical outcomes, integrating findings from whole-exome, transcriptome, and histologic analysis. For 128 patients treated with a first-line next-generation androgen receptor signaling inhibitor (ARSI; abiraterone or enzalutamide), we examined the association of 18 recurrent DNA- and RNA-based genomic alterations, including androgen receptor (
AR
) variant expression, AR transcriptional output, and neuroendocrine expression signatures, with clinical outcomes. Of these, only
RB1
alteration was significantly associated with poor survival, whereas alterations in
RB1
,
AR
, and
TP53
were associated with shorter time on treatment with an ARSI. This large analysis integrating mCRPC genomics with histology and clinical outcomes identifies
RB1
genomic alteration as a potent predictor of poor outcome, and is a community resource for further interrogation of clinical and molecular associations.
Femtosecond laser-heating effect on the magnetization dynamics in perpendicularly magnetized Ta/CoFeB/MgO film
Authors: Liu Bo , Yang Long , Ruan Xuezhong , Cai Jian-Wang , He Liang , Meng Hao , Wu Jing , Xu Yongbing
Published: May 2019

We have studied the effect of ultrafast laser-heating on the magnetization dynamics of perpendicularly magnetized CoFeB film by means of the time-resolved magneto-optical Kerr rotation effect. The effective perpendicular magnetic anisotropy field

H

K

is significantly decreased with enhancing the pump laser-fluence in a moderate range of 5–12 mJ cm−2. The Gilbert damping, however, is found to be independent of the pump fluence. These findings provide a new method of separately manipulating the Gilbert damping and perpendicular magnetic anisotropy.
A Preliminary Study for Simple Physics Models of Coconut Tree
Authors: Rahmawati  , Rahmayanti HD , Amalia N , Utami FD , Viridi S , Abdullah M
Published: May 2019

An investigation of how coconut palm tree withstands gale force winds has been performed. When observed carefully, the motion of the stalks and leaves affected the wind resistance. The stalks and leaves move randomly when the wind blows continously. Although this is such an interesting phenomenon, there is still no report on the physical modelling. This paper proposes a simple mathematical model to analyze the phenomenon. A simple tool was also designed to retrieve data usingVideo Tracker. The experiments were conducted on several types of springs. The model showed that the theoretical prediction accurately explained the phenomenon.
To mathematical modeling of deformation of micropolar thin bodies with two small sizes
Authors: Nikabadze M , Ulukhanyan A , Sakhvadze G
Published: May 2019

We consider some problems of modeling the deformation of micropolar thin bodies with two small sizes. Using the three-dimensional equations of motion, the constitutive relations and the boundary conditions of the micropolar elasticity theory [1, 2], we got the equations of motion, the constitutive relations and the boundary conditions of the micropolar theory of thin bodies under the parametrization of the thin body domain with two small sizes [3]. The boundary conditions and various representations of the system of equations of motion and the constitutive relations of physical content in moments with respect to the Legendre polynomials are obtained. Note that using this method of construction the thin bodies theory with two small sizes, we get an infinite system of ordinary differential equations. This system contains quantities which depends on one variable, namely, depends on the parameter of the base line. Thus, decreasing the number of independent variables from three to one we increase the number of equations to infinity, which, of course, has its obvious practical inconveniences. In this regard, we reduce an infinite system to the finite system. The initial-boundary value problems are formulated. To satisfy the boundary conditions on the front surfaces we constructed correcting terms [4]. As a special case, we considered a prismatic body. We used the tensor calculus to do this research [5–8].
Genetic Testing in the Diagnosis and Biology of Myeloid Neoplasms (Excluding Acute Leukemias)
Authors: Hasserjian Robert P , Kelley Todd W , Weinberg Olga K , Morgan Elizabeth A , Fend Falko
Published: May 2019

Objectives

The 2017 Workshop of the Society for Hematopathology/European Association for Haematopathology reviewed the role of genetic testing in the diagnosis of hematopoietic neoplasms, including non–acute leukemia myeloid malignancies.

Methods

The workshop panel assigned 98 submitted cases to the category of non–acute leukemia myeloid neoplasms, of which 13 were selected for oral presentation.

Results

Data from both conventional karyotyping and genetic sequencing had important impact on diagnosis, classification, and prognostication. However, some cases had genetic results that appeared discordant from the morphology and/or clinical features. Thus, the workshop underscored the need for careful management of genetic data by the pathologist and clinician, in the context of other findings.

Conclusions

The workshop cases highlighted the significance of genetic aberrations in the diagnosis and treatment of non–acute leukemia myeloid neoplasms. Many genetic data have already been incorporated in the most recent World Health Organization classification, and undoubtedly they will factor increasingly in future classifications.
Stress-Induced Sensitization of Angiotensin II Hypertension Is Reversed by Blockade of Angiotensin-Converting Enzyme or Tumor Necrosis Factor-α
Authors: Xue Baojian , Yu Yang , Wei Shun-Guang , Beltz Terry G , Guo Fang , Felder Robert B , Johnson Alan Kim
Published: May 2019

BACKGROUND

Post-traumatic stress disorder (PTSD) is characterized by a disordered stress response and associated with increased cardiovascular disease risk. The present study investigated whether angiotensin (Ang) II-elicited hypertensive response is sensitized in a model of PTSD and whether inhibition of angiotensin-converting enzyme (ACE) or tumor necrosis factor (TNF)-α prior to PTSD blocks this sensitization of Ang II hypertension.

METHODS

The resident–intruder paradigm was used to model PTSD. Each intruder rat (male Sprague-Dawley) was given normal drinking water or was pretreated with either an ACE inhibitor (captopril) or a TNF-α inhibitor (pentoxifylline) in the drinking water for 2 weeks. Subsequently, they were exposed to a different resident (male Long-Evans) for 2 hours on 3 days with each session separated by 1 day and then received a subcutaneous infusion of Ang II for 2 weeks.

RESULTS

The stressed rats had a significantly enhanced hypertensive response to the Ang II infusion (stressed Δ40.2 ± 3.9 mm Hg vs. unstressed Δ20.5 ± 4.5 mm Hg) and an upregulation of mRNA or protein expression of renin–angiotensin system (RAS) and proinflammatory cytokine (PIC) components and of a microglial marker in the lamina terminalis and hypothalamic paraventricular nucleus when compared with unstressed control rats. Both the sensitized hypertensive response and enhanced gene and protein expression were blocked by pretreatment with either ACE (Δ21.3 ± 3.9 mm Hg) or TNF-α inhibitor (Δ21.4 ± 2.6 mm Hg).

CONCLUSIONS

The results indicate that upregulation of the brain RAS and PICs produced by severe stress contributes to traumatic-induced sensitization of hypertensive response to Ang II, and disorders such as PTSD may predispose individuals to development of hypertension.
Oviposition Preference and Larval Performance of Drosophila suzukii (Diptera: Drosophilidae), Spotted-Wing Drosophila: Effects of Fruit Identity and Composition
Authors: Olazcuaga Laure , Rode Nicolas O , Foucaud Julien , Facon Benoit , Ravigné Virginie , Ausset Aurélien , Leménager Nicolas , Loiseau Anne , Gautier Mathieu , Estoup Arnaud , Hufbauer Ruth A
Published: May 2019

A better understanding of the factors affecting host plant use by spotted-wing drosophila (Drosophila suzukii) could aid in the development of efficient management tools and practices to control this pest. Here, proxies of both preference (maternal oviposition behavior) and performance (adult emergence) were evaluated for 12 different fruits in the form of purees. The effect of the chemical composition of the fruits on preference and performance traits was then estimated. We synthesized the literature to interpret our findings in the light of previous studies that measured oviposition preference and larval performance of D. suzukii. We show that fruit identity influences different parts of the life cycle, including oviposition preference under both choice and no-choice conditions, emergence rate, development time, and number of emerging adults. Blackcurrant was always among the most preferred fruit we used, while grape and tomato were the least preferred fruits. Larvae performed better in cranberry, raspberry, strawberry, and cherry than in the other fruits tested. We found that fruit chemical compounds can explain part of the effect of fruit on D. suzukii traits. In particular, oviposition preference under choice conditions was strongly influenced by fruit phosphorus content. In general, the consensus across studies is that raspberry, blackberry, and strawberry are among the best hosts while blackcurrant, grape and rose hips are poor hosts. Our results generally confirm this view but also suggest that oviposition preferences do not necessarily match larval performances. We discuss opportunities to use our results to develop new approaches for pest management.
Alternative Retirement Paths and Cognitive Performance: Exploring the Role of Preretirement Job Complexity
Authors: Carr Dawn C , Willis Robert , Kail Ben Lennox , Carstensen Laura L
Published: May 2019

Background and Objectives

Recent research suggests that working longer may be protective of cognitive functioning in later life, especially for workers in low complexity jobs. As postretirement work becomes increasingly popular, it is important to understand how various retirement pathways influence cognitive function. The present study examines cognitive changes as a function of job complexity in the context of different types of retirement transitions.

Research Design and Methods

We use data from the Health and Retirement Study (HRS) to examine change in cognitive function for workers who have held low, moderate, and high complexity jobs and move through distinct retirement pathways—retiring and returning to work, partial retirement—compared with those who fully retire or remain full-time workers. Inverse probability weighted regression adjustment (a propensity score method) is used to adjust for selection effects.

Results

There are systematic variations in the relationships between work and cognitive performance as a function of job complexity and retirement pathways. All retirement pathways were associated with accelerated cognitive decline for workers in low complexity jobs. In contrast, for high complexity workers retirement was not associated with accelerated cognitive decline and retiring and returning to work was associated with modest improvement in cognitive functioning.

Discussion and Implications

Both policy makers and individuals are beginning to embrace longer working lives which offer variety of potential benefits. Our findings suggest that continued full-time work also may be protective for cognitive health in workers who hold low complexity jobs.
Persistence and Lethality of a Fungal Biopesticide (Aprehend) Applied to Insecticide-impregnated and Encasement-type Box Spring Covers for Bed Bug Management
Authors: Shikano Ikkei , Gomez Lauren , Bellicanta Giovani S , Jenkins Nina E
Published: May 2019

The newly developed fungal biopesticide Aprehend, containing spores of Beauveria bassiana, is the first biological control agent to be incorporated into management programs to control the common bed bug (Cimex lectularius L.) (Hemiptera: Cimicidae). Aprehend is sprayed as barriers where bed bugs are likely to walk and pick up spores as they search for a bloodmeal. A key application target for Aprehend is the box spring, which may be covered by encasement-type or insecticide-impregnated covers. Since some insecticides can reduce the persistence of fungal spores, we tested the efficacy and spore germination percentages of Aprehend when applied to the two types of box spring covers. We found that spore germination was about 11% lower on the permethrin-impregnated ActiveGuard cover than on the encasement-type AllerEase cover. However, bed bugs exposed for 15 min to Aprehend on the two box spring covers suffered similarly high levels of mortality irrespective of the cover material. Thus, there was no inhibitory or additive effect of the ActiveGuard cover on bed bug mortality. Lastly, overall mortality was higher if bed bugs were exposed to Aprehend-treated ActiveGuard than the ActiveGuard cover alone. Our findings indicate that if pest managers are using ActiveGuard covers in combination with Aprehend, best practice would be to use ActiveGuard on mattresses and apply Aprehend directly to the box spring or to a box spring covered by an encasement-type cover.
Evaluation of Appropriate Reference Genes For Investigating Gene Expression in Chlorops oryzae (Diptera: Chloropidae)
Authors: Tian Ping , Qiu Lin , Zhou Ailin , Chen Guo , He Hualiang , Ding Wenbing , Li Youzhi
Published: May 2019

Reverse transcription quantitative polymerase chain reaction (PCR) has become an invaluable technique for analyzing gene expression in many insects. However, this approach requires the use of stable reference genes to normalize the data. Chlorops oryzae causes significant economic damage to rice crops throughout Asia. The lack of suitable reference genes has hindered research on the molecular mechanisms underlying many physiological processes of this species. In this study, we used quantitative real-time PCR to evaluate the expression of eight C. oryzae housekeeping genes glyceraldehyde-3-phosphate dehydrogenase (GAPDH), β-actin (βACT), beta-tubulin (βTUB), Delta Elongation factor-1 (EF1δ), ribosomal protein S11 (RPS11), RPS15, C-terminal-Binding Protein (CtBP), and ribosomal protein 49 (RP49) in different developmental stages and tissues in both larvae and adults. We analyzed the data with four different software packages: geNorm, NormFinder, BestKeeper, and RefFinder and compared the results obtained with each method. The results indicate that PRS15 and RP49 can be used as stable reference genes for quantifying gene expression in different developmental stages and larval tissues. GAPDH and βACT, which have been considered stable reference genes by previous studies, were the least stable of the candidate genes with respect to larval tissues. GAPDH was, however, the most stable reference gene for adult tissues. We verified the candidate reference genes identified and found that the expression levels of Cadherins (Cads) changed when different reference genes were used to normalize gene expression. This study provides a valuable foundation for future research on gene function, and investigating the molecular basis of physiological processes, in C. oryzae.
Implications of forest management practices for sex-specific habitat use by Nycticeius humeralis
Authors: Kwon Youngsang , Doty Anna C , Huffman Megan L , Rolland Virginie , Istvanko Daniel R , Risch Thomas S
Published: May 2019

North American bats are experiencing declines in part due to anthropogenic impacts resulting in habitat loss and disturbance. In eastern deciduous forests, bats rely on forest resources for all or part of the year. Therefore, to promote conservation of bats, it is essential to determine whether current forest management techniques are compatible with habitat use by bats. We evaluated the relative effect of landscape characteristics, including forest management variables, on sex-specific foraging habitat of an insectivorous forest-dwelling bat species, the evening bat (Nycticeius humeralis), and predicted areas of suitable habitat for N. humeralis. A total of 18 variables were assessed using a maximum-entropy (Maxent) machine-learning approach: eight land use–land cover classes, three stand types, two topography measures, normalized difference vegetation index, and four forest management variables. Females showed the highest probability of presence closer to stands treated with prescribed fire, whereas males showed the highest probability of presence closer to reforested stands. In general, males exhibited more flexibility than females in their habitat selection. The Maxent model further indicated that habitat associated with suitability of > 70% was ~4 times larger for males than females, and predicted an additional area of suitable foraging habitat where no presence locations had been recorded. Our modeling approach may be suitable for other researchers to derive models appropriate for a wide range of bat species.
See how they ran: morphological and functional aspects of skeletons from ancient Egyptian shrew mummies (Eulipotyphla: Soricidae: Crocidurinae)
Authors: Woodman Neal , Wilken Alec T , Ikram Salima
Published: May 2019

Animals served important roles in the religious cults that proliferated during the Late (ca. 747–332 BCE) and Greco-Roman Periods (332 BCE–CE 337) of ancient Egypt. One result was the interment of animal mummies in specialized necropolises distributed throughout the country. Excavation of a rock-tomb that was re-used during the Ptolemaic Period (ca. 309–30 BCE) for the interment of animal mummies at the Djehuty Site (TT 11–12) near Luxor, Egypt, was carried out in early 2018 by a Spanish–Egyptian team sponsored by the Consejo Superior de Investigaciones Científicas, Madrid. The tomb burned sometime after deposition of the mummies, leaving behind abundant disassociated skeletal remains, primarily of avians, but also including two species of shrews (Soricidae): Crocidura olivieri and C. religiosa. To investigate possible intraspecific variation in morphology and locomotor function in these two species during the last two millennia, we measured morphological features of individual postcranial bones from the two archaeological samples and calculated indices that have been used to assess locomotor function. We compared the measurements to those from modern C. olivieri, C. religiosa, and C. suaveolens using principal components analysis, and we compared locomotor indices to those we calculated for the three modern species of Crocidura and to those from nine species of myosoricine shrews. Osteological features of the postcranial skeleton of conspecific Ptolemaic and modern samples of C. olivieri and C. religiosa are generally similar in character and proportion, and, skeletally, these shrews and modern C. suaveolens are consistent with soricids having a primarily ambulatory locomotor mode. One exception is the deltopectoral crest of the humerus, which appears to be longer in modern C. religiosa. Despite general conservation of form and function, Ptolemaic C. olivieri had larger body size than modern Egyptian populations and were more similar in size to modern C. olivieri nyansae from Kenya than to modern C. olivieri olivieri from Egypt.
Protein Melting Temperature Cannot Fully Assess Whether Protein Folding Free Energy Underlies the Universal Abundance–Evolutionary Rate Correlation Seen in Proteins
Authors: Razban Rostam M
Published: May 2019

The protein misfolding avoidance hypothesis explains the universal negative correlation between protein abundance and sequence evolutionary rate across the proteome by identifying protein folding free energy (ΔG) as the confounding variable. Abundant proteins resist toxic misfolding events by being more stable, and more stable proteins evolve slower because their mutations are more destabilizing. Direct supporting evidence consists only of computer simulations. A study taking advantage of a recent experimental breakthrough in measuring protein stability proteome-wide through melting temperature (Tm) (Leuenberger et al. 2017), found weak misfolding avoidance hypothesis support for the Escherichia coli proteome, and no support for the Saccharomyces cerevisiae, Homo sapiens, and Thermus thermophilus proteomes (Plata and Vitkup 2018). I find that the nontrivial relationship between Tm and ΔG and inaccuracy in Tm measurements by Leuenberger et al. 2017 can be responsible for not observing strong positive abundance–Tm and strong negative Tm–evolutionary rate correlations.
Poor dietary intake of nutrients and food groups are associated with increased risk of periodontal disease among community-dwelling older adults: a systematic literature review
Authors: O’Connor Jessie-Leigh P , Milledge Kate L , O’Leary Fiona , Cumming Robert , Eberhard Joerg , Hirani Vasant
Published: May 2019

Context

Periodontal disease is a chronic inflammatory gum condition that is more prevalent in older populations. The development of periodontal disease has been directly linked to inflammatory dietary habits.

Objective

This systematic review aimed to 1) describe the relationship and 2) describe the direction of the relationship between dietary intake (nutrients and food groups) and periodontal disease in community-dwelling, older adults. PRISMA guidelines were followed for this review.

Data Sources

A systematic search of the databases MEDLINE, EMBASE, Global Health, CINAHL, Science Direct, Informit, and Cochrane Library was conducted from the earliest possible date until September 2018. Search terms were related to main themes: “periodontal disease,” “gingivitis,” “gum diseases,” “dietary intake” and “older adults.” The search produced 779 records, and after additional publications were obtained and duplicates were removed, 666 publications underwent title and abstract screening. Included papers were written in English and were based on populations of healthy, older adults living in community-based settings. Nine papers met inclusion criteria and were included in this review.

Data Extraction

Sample size, participant characteristics, inclusion and exclusion criteria, periodontal measures, dietary measures, confounders, and results were sorted by study type, author, year, and country.

Data Analysis

Quality of the extracted data was analyzed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system.

Conclusions

Inverse associations were found between fatty acids, vitamin C, vitamin E, beta-carotene, fiber, calcium, dairy, fruits, and vegetables and risk of periodontal disease. Overall, this review found a relationship between poor dietary intake and increased risk of periodontal disease; however, this needs to be further explored.

Systematic Review Registration

PROSPERO Registration Number CRD42017065022.
NATURAL RADIUM ISOTOPES PRESENT IN SOME COSMETIC PRODUCTS: DETERMINATION OF ACTIVITY CONCENTRATION AND DOSE ESTIMATION
Authors: Milena-Pérez A , Martínez-Martínez B R , Álvarez E , Expósito-Suárez V M , Piñero-García F , Ferro-García M A
Published: May 2019

Since the early days, clays, plant extracts and raw materials have been used for therapeutic and beauty purposes. Nowadays, this use is widely spread, as a huge amount of companies have developed new cosmetics based on natural sources. This may lead to an accumulation of radionuclides that can be hazardous for people. Especially dangerous are radium isotopes (226,228Ra), which can be part of the raw materials that cosmetics are made from. In this paper, the concentration of radium isotopes of 18 natural cosmetics was determined. Concentrations resulted in the range 7.9 ± 5.0–37.6 ± 12.5 Bq kg−1 for 226Ra; and 2.5 ± 1.7–35.4 ± 2.6 Bq kg−1 for 228Ra. The effective dose in the skin has been estimated, obtaining a mean value of 13.1 ± 4.9 μSv y−1. This value is far from the reference level of 50 mSv y−1 for the public members. Therefore, no radiological risk derived from the use of these samples, has been found.
Association of the phenylpropanoid pathway with dormancy and adaptive trait variation in apricot (Prunus armeniaca)
Authors: Conrad Anna O , Yu Jiali , Staton Margaret E , Audergon Jean-Marc , Roch Guillaume , Decroocq Veronique , Knagge Kevin , Chen Huadong , Zhebentyayeva Tetyana , Liu Zongrang , Dardick Christopher , Nelson C Dana , Abbott Albert G
Published: May 2019

Trees use many mechanisms to adapt and respond to stressful conditions. The phenylpropanoid pathway in particular is known to be associated with a diverse suite of plant stress responses. In this study, we explored the relationship between the phenylpropanoid pathway metabolite production, gene expression and adaptive trait variation associated with floral bud reactivation during and following dormancy in Prunus armeniaca L. (apricot). Concentrations of eight phenylpropanoid metabolites were measured during chill accumulation and at developmental stages corresponding to the emergence of sepals and petals in floral buds of varieties that differ phenotypically in bloom date (BD). A significant interaction effect of chill hours and BD phenotype on the concentration of each of the compounds was observed (mixed analysis of variance, P < 0.05), with the concentration of most phenylpropanoid metabolites dropping precipitously when sepals and petals emerged. While phenylpropanoid biosynthetic gene expression patterns were more variable in general, expression changed over time and was impacted, although to a lesser degree, by BD phenotype. Furthermore, separation of BD phenotypic groups was most pronounced when early and late BD varieties were at different developmental stages, i.e., 800 chill hours. Taken together, these results suggest that the phenylpropanoid pathway is associated with floral bud reactivation in apricot. Furthermore, we show that the phenylpropanoid pathway is also impacted by phenological trait variation associated with dormancy. A better understanding of how apricot and other perennial tree species respond and adapt to environmental perturbations will be critical for improvement programs aimed at identifying and breeding trees more suitable for rapidly changing environments.