bluuebunny/crossref_metadata_2025 huggingface dataset:
Relaxin‐3 inputs target hippocampal interneurons and deletion of hilar relaxin‐3 receptors in “floxed‐RXFP3” mice impairs spatial memory
Authors: Haidar M. , Guèvremont G. , Zhang C. , Bathgate R.A.D. , Timofeeva E. , Smith C.M. , Gundlach A.L.
Published: January 2017

Hippocampus is innervated by γ‐aminobutyric acid (GABA) “projection” neurons of the nucleus incertus (NI), including a population expressing the neuropeptide, relaxin‐3 (RLN3). In studies aimed at gaining an understanding of the role of RLN3 signaling in hippocampus via its Gi/o‐protein‐coupled receptor, RXFP3, we examined the distribution of RLN3‐immunoreactive nerve fibres and RXFP3 mRNA‐positive neurons in relation to hippocampal GABA neuron populations. RLN3‐positive elements were detected in close‐apposition with a substantial population of somatostatin (SST)‐ and GABA‐immunoreactive neurons, and a smaller population of parvalbumin‐ and calretinin‐immunoreactive neurons in different hippocampal areas, consistent with the relative distribution patterns of RXFP3 mRNA and these marker transcripts. In light of the functional importance of the dentate gyrus (DG) hilus in learning and memory, and our anatomical data, we examined the possible influence of RLN3/RXFP3 signaling in this region on spatial memory. Using viral‐based Cre/LoxP recombination methods and adult mice with a floxed Rxfp3 gene, we deleted Rxfp3 from DG hilar neurons and assessed spatial memory performance and affective behaviors. Following infusions of an AAV(1/2)‐Cre‐IRES‐eGFP vector, Cre expression was observed in DG hilar neurons, including SST‐positive cells, and in situ hybridization histochemistry for RXFP3 mRNA confirmed receptor depletion relative to levels in floxed‐RXFP3 mice infused with an AAV(1/2)‐eGFP (control) vector. RXFP3 depletion within the DG hilus impaired spatial reference memory in an appetitive T‐maze task reflected by a reduced percentage of correct choices and increased time to meet criteria, relative to control. In a continuous spontaneous alternation Y‐maze task, RXFP3‐depleted mice made fewer alternations in the first minute, suggesting impairment of spatial working memory. However, RXFP3‐depleted and control mice displayed similar locomotor activity, anxiety‐like behavior in light/dark box and elevated‐plus maze tests, and learning and long‐term memory retention in the Morris water maze. These data indicate endogenous RLN3/RXFP3 signaling can modulate hippocampal‐dependent spatial reference and working memory via effects on SST interneurons, and further our knowledge of hippocampal cognitive processing. © 2017 Wiley Periodicals, Inc.
Failures of foreseeability: Risk management considerations in reducing allegations of sexual violence in psychiatric units
Authors: Banja John D.
Published: January 2017

This article begins with a brief discussion of findings on causal factors leading to allegations of sexual violence in health care facilities and then offers the author’s account of 4 such cases that he reviewed, 3 of which occurred in psychiatric units. These cases show remarkably similar variables, especially involving decisions to allow male and female patients to commingle, the inadequate physical layout of the units, poor or absent video surveillance, and staff unacquainted with institutional policies on patient safety or refusing to enforce relevant rules. These variables arguably amount to “failures of foreseeability” that reasonably cautious health care personnel should recognize as facilitating or enabling sexual violence. As such, the proactive message of this article for health care risk management urges critical and robust attention paid to a unit’s environmental/physical design as well as to performance factors among personnel so as to prevent sexual attacks and diminish the probability of malpractice actions.
A qualitative study to describe patient‐specific factors that relate to clinical need for and potential to benefit from a medication management service in palliative care
Authors: Cortis Lauren J.
Published: January 2017

Background

In 2011, an advanced practice role was introduced to a specialist regional palliative care service to support an expansion of the number of palliative care home medicines reviews.

Aim

To gain insight into which types of community‐based palliative care patients benefit from medication management services in order to guide local service development.

Method

Thematic analysis of a case series of medication reviews conducted by the palliative care pharmacist.

Results

Over a 12‐week period, 15 medication reviews were conducted and analysed. Four patient categories that related to a clinical need and potential to benefit from a medication review were identified: managing a chronic disease as well as cancer; experiencing ongoing generalised symptoms; having existing or anticipated problems with swallowing or digestion; and having a recognised falls risk. Most patients fit into more than one category.

Conclusion

There is significant opportunity for pharmacists to enhance the quality of life of palliative care patients through improved use of medicines; however, incorporating the existing home medicine review program does not appear to be the most appropriate method for achieving this due to the program design. Delivering best outcomes for palliative care patients requires models of care that support communication and collaboration across the entire healthcare team and facilitate trusting therapeutic relationships between pharmacists and patients. Integration of advanced generalist pharmacists into clinical care teams is a positive step toward improving patient outcomes in palliative care.
The Posttraumatic Growth Inventory: A Revision Integrating Existential and Spiritual Change
Authors: Tedeschi Richard G. , Cann Arnie , Taku Kanako , Senol‐Durak Emre , Calhoun Lawrence G.
Published: January 2017

Spiritual Change (SC) is one of 5 domains of posttraumatic growth (PTG). The current Posttraumatic Growth Inventory (PTGI) assesses this area of growth with only 2 items, one focusing on religiosity and the other focusing on spiritual understanding. The addition of 4 newly developed spiritual–existential change (SEC) items, creating an expanded PTGI (Posttraumatic Growth Inventory‐X), reflects a diversity of perspectives on spiritual–existential experiences that are represented in different cultures. Samples were obtained from 3 countries: the United States (n = 250), Turkey (n = 502), and Japan (n = 314). Analyses indicated that the newly added items capture additional experiences of growth outside traditional religious concepts, yet still are correlated with the original SC items, especially in the U.S. and Turkish samples. Relationships of the PTGI‐X to established predictors of PTG, event‐related rumination, and core beliefs, were as predicted in all 3 countries. The new 6‐item SEC factor demonstrated high internal reliability, and the 5‐factor structure of the expanded scale was supported by confirmatory factor analysis. The resulting 25‐item PTGI‐X can be used as a validated instrument in a wide range of samples in which traditional religious beliefs are less dominant.
Regional‐scale models for predicting overwinter survival of juvenile ungulates
Authors: Hurley Mark A. , Hebblewhite Mark , Lukacs Paul M. , Nowak J. Joshua , Gaillard Jean‐Michel , Bonenfant Christophe
Published: January 2017

Juvenile survival is highly variable in ungulate populations and often influences their dynamics. However, this vital rate is difficult to estimate with common wildlife management methods. Yet managers would benefit from being able to predict juvenile survival to reliably assess population dynamics for harvest management. In the case of mule deer (Odocoileus hemionus), previous studies reported that overwinter survival is the demographic parameter that influences population dynamics. We predicted winter survival of mule deer fawns under a range of habitat quality, weather, and predation regimes. We modeled overwinter survival of 2,529 fawns within 11 Population Management Units (PMU) in Idaho, 2003–2013. We used remotely sensed Normalized Difference Vegetation Index (NDVI) as a measure of summer plant productivity and both Moderate Resolution Infrared Spectroscopy Snow Data (MODIS SNOW) and the modeled Snow Data Assimilation System (SNODAS) as measures of winter snow conditions to capture spatiotemporal variation in winter survival. We used Bayesian hierarchical models to estimate survival, including covariates at the appropriate spatial and temporal resolution for each level: individual, capture site, PMU, and ecotype scales. We evaluated the predictive capacity of models using internal validation and external (out‐of‐sample) validation procedures comparing non‐parametric Kaplan‐Meier (KM) survival estimates with estimates from Bayesian hierarchical models. Statewide survival of fawns from 16 December to 1 June ranged from 0.32 to 0.71 during 2003 to 2013, with relatively low survival in 2006, 2008, and 2011 in most Game Management Units. Survival for individual PMUs ranged from 0.09 in the Weiser‐McCall PMU in 2011 to 0.95 in the same PMU in 2005. Internal validation revealed models predicted KM survival well, over a range of R2 from 0.78 to 0.82, with the most complex model explaining the most variance as expected. However, because our goal was to predict winter survival of mule deer in the future, we evaluated our candidate models by withholding 2 years of data and then predicted those years with each model. The best‐supported predictive model was our simplest model with 3 covariates, accounting for 71% of the variance in withheld years. Forage quality in late summer‐fall increased winter mule deer survival, whereas early and late winter snow cover decreased survival. At finer‐spatial scales within ecotypes, our internal validation was slightly better in aspen (0.86), similar in conifer (0.80), and poorer in shrub‐steppe (0.60) ecotypes than our best statewide overall survival models, which accounted for 82% of the variance. Our analyses demonstrate the generality versus precision tradeoff across ecotypes and spatial scales to understand the extent that our survival models may be applied to different landscapes with varied predator communities, climate, and plant nutrition. © 2016 The Wildlife Society.
High‐Performance and Low Migration One‐Component Thioxanthone Visible Light Photoinitiators
Authors: Wu Qingqing , Tang Kuangyi , Xiong Ying , Wang Xiaoling , Yang Jianjing , Tang Hongding
Published: January 2017

Two thioxanthone based acrylated one‐component visible light photoinitiators, 2‐(methyl(4‐((methyl(9‐oxo‐9H‐thioxanthen‐2‐yl)amino)methyl)benzyl)amino)ethyl acrylate (TX‐EA) and ((4‐((methyl(9‐oxo‐9H‐thioxanthen‐2‐yl)amino)methyl)benzyl)azanediyl)bis(ethane‐2,1‐diyl)diacrylate (TX‐BDA), are designed and synthesized. The results of photopolymerization and migration study demonstrate that TX‐EA and TX‐BDA are more effective one‐component visible light photoinitiators for free radical polymerization with excellent migration stability than 4‐((methyl(9‐oxo‐9H‐thioxanthen‐2‐yl)amino)methyl)phenyl acrylate. The mass fraction of the extracted TX‐BDA in a cured 1,6‐hexanediol diacrylate polymer film is as low as 0.55% and the residual amount is estimated to be only 90 ppm. TX‐BDA would have great potential to be used in visible light curing systems, particularly in the food packing or biomedical fields. Results demonstrate that the synergistic effect of hydrogen donors and polymerizable groups in photoinitiator plays an important role in realizing high performance and low migration in photopolymerization system.

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Carbon Fibers Prepared from Melt Spun Peracylated Softwood Lignin: an Integrated Approach
Authors: Steudle Lisa M. , Frank Erik , Ota Antje , Hageroth Ulrich , Henzler Sabine , Schuler Winfried , Neupert Rolf , Buchmeiser Michael R.
Published: January 2017

Different softwood lignin O‐acyl derivatives, i.e., methacrylated, hexanoylated, benzoylated, methoxybenzoylated, and cinnamoylated lignin are synthesized and subjected to melt spinning. In the presence of spinning aids such as vanillin and ethylene glycol dimethacrylate, multifilament melt spinning is accomplished with spinning speeds up to 500 m min−1, which allowed for realizing uniform precursor fibers 17 μm in diameter. Out of all acyl‐derivatives of softwood lignin investigated, cinnamoylated softwood lignin (CL) turned out to be superior in terms of processability. CL‐derived precursor fibers are oxidatively thermostabilized and then carbonized applying carbonization temperatures up to 2200 °C. Carbon fiber structure formation is followed in detail by wide‐angle X‐ray scattering and Raman spectroscopy. An orientation ≤53% and a d
002 spacing of 0.353 nm is achieved. According to small angle X‐ray scattering, carbon fibers have a porosity of ≈38%. CL‐derived carbon fibers are also characterized in terms of mechanical properties. Tensile strengths up to 0.93 GPa (average 0.75 GPa) are obtained and follow Weibull statistics. Elastic moduli are ≤66.5 GPa (average 41.1 GPa).

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Global well‐posedness of 2D nonlinear Boussinesq equations with mixed partial viscosity and thermal diffusivity
Authors: Chen Chao , Liu Jitao
Published: January 2017

In this paper, we discuss with the global well‐posedness of 2D anisotropic nonlinear Boussinesq equations with any two positive viscosities and one positive thermal diffusivity. More precisely, for three kinds of viscous combinations, we obtain the global well‐posedness without any assumption on the solution. For other three difficult cases, under the minimal regularity assumption, we also derive the unique global solution. To the authors' knowledge, our result is new even for the simplified model, that is, F(θ) = θe2. Copyright © 2017 John Wiley & Sons, Ltd.
Attractors for the strongly damped wave equation with p‐Laplacian
Authors: Khanmamedov Azer , Sen Zehra
Published: January 2017

This paper is concerned with the initial‐boundary value problem for one‐dimensional strongly damped wave equation involving p‐Laplacian. For p > 2 , we establish the existence of weak local attractors for this problem in
. Under restriction 2 < p < 4, we prove that the semigroup, generated by the considered problem, possesses a strong global attractor in
, and this attractor is a bounded subset of
. Copyright © 2017 John Wiley & Sons, Ltd.
Monte Carlo simulations of ceiling scatter in nuclear medicine: 99mTc, 131I and 18F
Authors: Schnerr Roald S. , de Jong Anouk N. , Landry Guillaume , Jeukens Cécile R.L.P.N. , Wierts Roel
Published: January 2017

Purpose

In the design of nuclear medicine treatment and examination rooms, an important consideration is the shielding required for ionizing radiation from the radioactive isotopes used. The shielding in the walls is normally limited to a height lower than the actual ceiling height. The direct radiation, possibly with build‐up correction, can be calculated relatively easily. However, little data are available to estimate the dose contribution from ionizing radiation traveling over the wall shielding and scattering off the ceiling. We aim to determine the contribution of the ceiling scatter to the radiation dose outside nuclear medicine rooms.

Methods

Monte Carlo simulations were performed using Gate for different heights of lead shielding in the wall, and different ceiling heights. A point source in air of 99mTc (141 keV), 131I (365 keV) or 18F (511 keV) was placed 1.0 m above the floor, 3.0 m from the lead shielding. Simulations of ceiling scatter only and for the total radiation dose were performed for these 3 isotopes, 5 different ceiling heights and 4–8 different wall shielding heights, resulting in a total of 165 simulations. This allowed us to compare the contribution of the radiation passing through the shielding and the ceiling scatter.

Results

We find that the shielding required for the primary radiation, measured in half‐value layers, is an important factor in determining the relative contribution of ceiling scatter. When more than about 4 half‐value layers of shielding are used, ceiling scatter becomes the dominant factor and should be taken into account in the shielding design. In many practical cases for low energy photons (e.g. from 99mTc; 141 keV; half‐value layer of 0.26 mm lead), 2 mm of lead is used and ceiling scatter is a dominating factor contributing >~70% of the dose outside the shielded room. For higher energies (e.g. 18F; 511 keV; half‐value layer of 3.9 mm lead) the ceiling scatter is typically less than about 15% when 8 mm of lead shielding is used.

Conclusions

We have performed simulations that allow an estimation of the contribution of ceiling scatter to the radiation dose outside a room, based on the ceiling height, shielding height, and isotope used. This will allow for improved shielding designs in nuclear medicine departments.
Technical Note: Fast respiratory motion estimation using sorted singles without unlist processing: A feasibility study
Authors: Yang Jaewon , Khalighi Mehdi , Hope Thomas A. , Ordovas Karen , Seo Youngho
Published: January 2017

Purpose

The study aims to demonstrate the feasibility of fast respiratory motion estimation using singles data available as a sorted format in list‐mode files acquired in an integrated positron emission tomography/magnetic resonance imaging (PET/MRI) system for a proof‐of‐concept.

Methods

The derivation of singles‐driven respiratory motion (SDRM) is enabled by singles recorded and binned by second for each detector crystal in PET list‐mode data acquired in a SIGNA PET/MR. The proposed method is to derive a SDRM trace by summing up all singles from all detectors through the PET data acquisition. To assess the feasibility of SDRM for data‐driven gating (DDG), SDRM traces were derived from the list‐mode data acquired in five liver‐focused 68Ga‐DOTA‐TOC PET/MRI scans, and compared with the traces derived from bellows (pressure belt). Pearson's correlation coefficients and trigger time differences at peak‐inhalation phases between SDRM and bellows traces were measured for quantitative evaluation.

Results

The method presented the average processing time of 4.2 ± 0.42 s (range: 3.9 ~ 4.7 s) for the derivation of SDRM traces. The majority of the time was spent for reading singles data from a list‐mode file (3.1 ± 0.40 s, range: 2.7 ~ 3.7s). On average, the correlation coefficient of SDRM and bellows traces was 0.69 ± 0.16 (range: 0.41 ~ 0.80) and the time offset of SDRM‐driven triggers from bellows‐driven triggers was 0.25 ± 0.39 s (range: −0.85 ~ 2.69 s later than bellows triggers), demonstrating the similar patterns and phases of SDRM and bellows traces.

Conclusions

We introduced PET singles‐driven respiratory motion (SDRM) estimation as a proof‐of‐principle, using sorted singles ready for immediate processing in list‐mode data. The results demonstrated the feasibility of SDRM and its potential use for gated PET with fast processing time.
Requirements for accurate estimation of anisotropic material parameters by magnetic resonance elastography: A computational study
Authors: Tweten D.J. , Okamoto R.J. , Bayly P.V.
Published: January 2017

Purpose

To establish the essential requirements for characterization of a transversely isotropic material by magnetic resonance elastography (MRE).

Theory and Methods

Three methods for characterizing nearly incompressible, transversely isotropic (ITI) materials were used to analyze data from closed‐form expressions for traveling waves, finite‐element (FE) simulations of waves in homogeneous ITI material, and FE simulations of waves in heterogeneous material. Key properties are the complex shear modulus μ2, shear anisotropy
, and tensile anisotropy
.

Results

Each method provided good estimates of ITI parameters when both slow and fast shear waves with multiple propagation directions were present. No method gave accurate estimates when the displacement field contained only slow shear waves, only fast shear waves, or waves with only a single propagation direction. Methods based on directional filtering are robust to noise and include explicit checks of propagation and polarization. Curl‐based methods led to more accurate estimates in low noise conditions. Parameter estimation in heterogeneous materials is challenging for all methods.

Conclusions

Multiple shear waves, both slow and fast, with different propagation directions, must be present in the displacement field for accurate parameter estimates in ITI materials. Experimental design and data analysis can ensure that these requirements are met. Magn Reson Med 78:2360–2372, 2017. © 2017 International Society for Magnetic Resonance in Medicine.
Click here for mental health support: Extending mental health services to the isolated learner, Part 2
Authors: Russo Joseph V. , Bruce Mary Alice , Scull Reed
Published: January 2017

In Part One of this two‐part series (see the January 2017 issue), the authors discussed a pilot program to provide telemental health services to the University of Wyoming's distance learners. Among the first of its kind in the United States, the program is intended to offer telemental health services to distance learners that are similar to those provided to on‐campus students. Distance students are typically nontraditional learners, including older adults who may be returning to school to up‐skill or returning servicemen and ‐women seeking to finish a degree.
Type III pleuropulmonary blastoma in a dicer1 germline mutation carrier: The management of residual lung cystic lesions
Authors: Fita Ana M. , Llinares‐Riestra Esther , Doménech‐Abellán Ernesto , Bermúdez‐Cortés Mar , Galera‐Miñarro Ana M. , Bas‐Bernal Agueda , Fuster‐Soler José L.
Published: January 2017

Pleuropulmonary blastoma (PPB) is a rare malignancy of childhood. It often represents a manifestation of a hereditary tumor predisposition syndrome (DICER1 syndrome). Because of its malignant potential, surgical resection of cystic lung lesions is recommended in germline DICER1 mutation carriers. We present a case of a 3‐year‐old male child with type III PPB successfully managed with ifosfamide, vincristine, actinomycin‐D, and doxorubicin (IVADo) chemotherapy and surgery. A heterozygous germline pR688X mutation of DICER1 gene was demonstrated. Six years after primary diagnosis, several small lung cysts remained stable without further therapy. The management of residual asymptomatic lung cysts represents a clinical challenge in these patients.
The McGill Interactive Pediatric OncoGenetic Guidelines: An approach to identifying pediatric oncology patients most likely to benefit from a genetic evaluation
Authors: Goudie Catherine , Coltin Hallie , Witkowski Leora , Mourad Stephanie , Malkin David , Foulkes William D.
Published: January 2017

Identifying cancer predisposition syndromes in children with tumors is crucial, yet few clinical guidelines exist to identify children at high risk of having germline mutations. The McGill Interactive Pediatric OncoGenetic Guidelines project aims to create a validated pediatric guideline in the form of a smartphone/tablet application using algorithms to process clinical data and help determine whether to refer a child for genetic assessment. This paper discusses the initial stages of the project, focusing on its overall structure, the methodology underpinning the algorithms, and the upcoming algorithm validation process.
A man‐made disease: Fetal neonatal alloimmune thrombocytopenia due to incompatibility between oocyte donor and gestational mother
Authors: Barg Assaf Arie , Ifrah Aviya Dvir , Strauss Tzipi , Simchen Michal J. , Orvieto Raoul , Rosenberg Nurit , Kenet Gili
Published: January 2017

The incompatibility causing fetal and neonatal alloimmune thrombocytopenia (FNAIT) results from a fetus inheriting a paternal human platelet antigen (HPA), which is different from the maternal HPA. We present a unique case of FNAIT in a pregnancy involving an oocyte recipient mother with Turner syndrome. This is the first report of FNAIT in which the suggested mechanism involves antibodies produced by a gestational mother against the incompatible HPA of the oocyte donor.
Toughened polyoxymethylene by polyolefin elastomer and glycidyl methacrylate grafted high‐density polyethylene
Authors: Yang Wenqing , Wang Xuan‐Lun , Yan Xingru , Guo Zhanhu
Published: January 2017

Ternary blends of polyoxymethylene (POM), polyolefin elastomer (POE), and glycidyl methacrylate grafted high density polyethylene (GMA‐g‐HDPE) with various component ratios were studied for their mechanical and thermal properties. The size of POE dispersed phase increased with increasing the elastomer content due to the observed agglomeration. The notched impact strength demonstrated a parabolic tendency with increasing the elastomer content and reached the peak value of 10.81 kJ/m2 when the elastomer addition was 7.5 wt%. The disappearance of epoxy functional groups in the POM/POE/GMA‐g‐HDPE blends indicated that GMA‐g‐HDPE reacted with the terminal hydroxyl groups of POM and formed a new graft copolymer. Higher thermal stability was observed in the modified POM. Both storage modulus and loss modulus decreased from dynamic mechanical analysis tests while the loss factor increased with increasing the elastomer content. GMA‐g‐HDPE showed good compatibility between the POM matrix and the POE dispersed phase due to the reactive compatibilization of the epoxy groups of GMA and the terminal hydroxyl groups of POM. A POM/POE blend without compatibilizer was researched for comparison, it was found that the properties of P‐7.5(POM/POE 92.5 wt%/7.5 wt%) were worse than those of the blend with the GMA‐g‐HDPE compatibilizer. POLYM. ENG. SCI., 57:1119–1126, 2017. © 2017 Society of Plastics Engineers
Chitosan‐based hydrogels: recent design concepts to tailor properties and functions
Authors: Racine Lisa , Texier Isabelle , Auzély‐Velty Rachel
Published: January 2017

Chitosan (CS) has received much attention as a functional biopolymer for designing various hydrogels for biomedical applications. This review provides an overview of the different types of CS‐based hydrogels, the approaches that can be used to fabricate hydrogel matrices with specific features and their applications in controlled drug delivery and tissue engineering. Emphasis is laid on the recent design concepts of hybrid hydrogels based on mixtures of CS and natural or synthetic polymers, interpenetrating polymer networks as well as composite hydrogels prepared by embedding nanoparticles into CS matrices. © 2017 Society of Chemical Industry
Silane‐functional benzoxazine: synthesis, polymerization kinetics and thermal stability
Authors: Zhang Wenkai , Gao Xiuxiu , Yu Lili , Ren Yanrong , Xu Hao , Liu Baoying , Wang Yanpeng , Fang Xiaomin , Xu Yuanqing , Ding Tao
Published: January 2017

A benzoxazine with siloxane and phenyl sulfone units (BS‐b) was synthesized by using aminopropyltriethoxysilane, 4,4'‐dihydroxydiphenylsulfone and paraformaldehyde as precursors via Mannich condensation. Then the hydrolysis and polycondensation reactions of siloxane units were performed and benzoxazine bearing polysiloxanes (BS‐PSO) were obtained. The ring‐opening polymerization reactions of both BS‐b and BS‐PSO were studied by Fourier transform IR spectroscopy and DSC in non‐isothermal conditions. The kinetics of the polymerization of BS‐b were found to be well described by using an nth‐order kinetic model for n = 0.7 (activation energy 141 kJ mol−1). The BS‐PSO was also used to modify bisphenol‐A‐based benzoxazines (BA‐a), and the morphological structure and thermal properties of the copolymer were investigated. The TGA results indicate that the silane‐functional polybenzoxazines display enhanced initial decomposition temperature and char yields in comparison with poly(BA‐a). These results are believed to be important for the development of new flame‐retardant laminates. © 2017 Society of Chemical Industry
Energetics, kinetics, and pathway of SNARE folding and assembly revealed by optical tweezers
Authors: Zhang Yongli
Published: January 2017

Soluble N‐ethylmaleimide‐sensitive factor attachment protein receptors (SNAREs) are universal molecular engines that drive membrane fusion. Particularly, synaptic SNAREs mediate fast calcium‐triggered fusion of neurotransmitter‐containing vesicles with plasma membranes for synaptic transmission, the basis of all thought and action. During membrane fusion, complementary SNAREs located on two apposed membranes (often called t‐ and v‐SNAREs) join together to assemble into a parallel four‐helix bundle, releasing the energy to overcome the energy barrier for fusion. A long‐standing hypothesis suggests that SNAREs act like a zipper to draw the two membranes into proximity and thereby force them to fuse. However, a quantitative test of this SNARE zippering hypothesis was hindered by difficulties to determine the energetics and kinetics of SNARE assembly and to identify the relevant folding intermediates. Here, we first review different approaches that have been applied to study SNARE assembly and then focus on high‐resolution optical tweezers. We summarize the folding energies, kinetics, and pathways of both wild‐type and mutant SNARE complexes derived from this new approach. These results show that synaptic SNAREs assemble in four distinct stages with different functions: slow N‐terminal domain association initiates SNARE assembly; a middle domain suspends and controls SNARE assembly; and rapid sequential zippering of the C‐terminal domain and the linker domain directly drive membrane fusion. In addition, the kinetics and pathway of the stagewise assembly are shared by other SNARE complexes. These measurements prove the SNARE zippering hypothesis and suggest new mechanisms for SNARE assembly regulated by other proteins.
Force generation by titin folding
Authors: Mártonfalvi Zsolt , Bianco Pasquale , Naftz Katalin , Ferenczy György G. , Kellermayer Miklós
Published: January 2017

Titin is a giant protein that provides elasticity to muscle. As the sarcomere is stretched, titin extends hierarchically according to the mechanics of its segments. Whether titin's globular domains unfold during this process and how such unfolded domains might contribute to muscle contractility are strongly debated. To explore the force‐dependent folding mechanisms, here we manipulated skeletal‐muscle titin molecules with high‐resolution optical tweezers. In force‐clamp mode, after quenching the force (<10 pN), extension fluctuated without resolvable discrete events. In position‐clamp experiments, the time‐dependent force trace contained rapid fluctuations and a gradual increase of average force, indicating that titin can develop force via dynamic transitions between its structural states en route to the native conformation. In 4 M urea, which destabilizes H‐bonds hence the consolidated native domain structure, the net force increase disappeared but the fluctuations persisted. Thus, whereas net force generation is caused by the ensemble folding of the elastically‐coupled domains, force fluctuations arise due to a dynamic equilibrium between unfolded and molten‐globule states. Monte–Carlo simulations incorporating a compact molten‐globule intermediate in the folding landscape recovered all features of our nanomechanics results. The ensemble molten‐globule dynamics delivers significant added contractility that may assist sarcomere mechanics, and it may reduce the dissipative energy loss associated with titin unfolding/refolding during muscle contraction/relaxation cycles.
Differential dehydration effects on globular proteins and intrinsically disordered proteins during film formation
Authors: Yoneda Juliana Sakamoto , Miles Andew J. , Araujo Ana Paula Ulian , Wallace B. A.
Published: January 2017

Globular proteins composed of different secondary structures and fold types were examined by synchrotron radiation circular dichroism spectroscopy to determine the effects of dehydration on their secondary structures. They exhibited only minor changes upon removal of bulk water during film formation, contrary to previously reported studies of proteins dehydrated by lyophilization (where substantial loss of helical structure and gain in sheet structure was detected). This near lack of conformational change observed for globular proteins contrasts with intrinsically disordered proteins (IDPs) dried in the same manner: the IDPs, which have almost completely unordered structures in solution, exhibited increased amounts of regular (mostly helical) secondary structures when dehydrated, suggesting formation of new intra‐protein hydrogen bonds replacing solvent‐protein hydrogen bonds, in a process which may mimic interactions that occur when IDPs bind to partner molecules. This study has thus shown that the secondary structures of globular and intrinsically disordered proteins behave very differently upon dehydration, and that films are a potentially useful format for examining dehydrated soluble proteins and assessing IDPs structures.
Molecular mechanisms underlying deoxy‐ADP.Pi activation of pre‐powerstroke myosin
Authors: Nowakowski Sarah G. , Regnier Michael , Daggett Valerie
Published: January 2017

Myosin activation is a viable approach to treat systolic heart failure. We previously demonstrated that striated muscle myosin is a promiscuous ATPase that can use most nucleoside triphosphates as energy substrates for contraction. When 2‐deoxy ATP (dATP) is used, it acts as a myosin activator, enhancing cross‐bridge binding and cycling. In vivo, we have demonstrated that elevated dATP levels increase basal cardiac function and rescues function of infarcted rodent and pig hearts. Here we investigate the molecular mechanism underlying this physiological effect. We show with molecular dynamics simulations that the binding of dADP.Pi (dATP hydrolysis products) to myosin alters the structure and dynamics of the nucleotide binding pocket, myosin cleft conformation, and actin binding sites, which collectively yield a myosin conformation that we predict favors weak, electrostatic binding to actin. In vitro motility assays at high ionic strength were conducted to test this prediction and we found that dATP increased motility. These results highlight alterations to myosin that enhance cross‐bridge formation and reveal a potential mechanism that may underlie dATP‐induced improvements in cardiac function.
Context characterization of amino acid homorepeats using evolution, position, and order
Authors: Mier Pablo , Alanis‐Lobato Gregorio , Andrade‐Navarro Miguel A.
Published: January 2017

Amino acid repeats, or homorepeats, are low complexity protein motifs consisting of tandem repetitions of a single amino acid. Their presence and relative number vary in different proteomes, and some studies have tried to address this variation, proteome by proteome. In this work, we present a full characterization of amino acid homorepeats across evolution. We studied the presence and differential usage of each possible homorepeat in proteomes from various taxonomic groups, using clusters of very similar proteins to eliminate redundancy. The position of each amino acid repeat within proteins, and the order of co‐occurring amino acid repeats were also addressed. As a result, we present evidence about the unevenly evolution of homorepeats, as well as the functional implications of their relative position in proteins. We discuss some of these cases in their taxonomic context. Collectively, our results show evolutionary and positional signals that suggest that homorepeats have biological function, likely creating unspecific protein interactions or modulating specific interactions in a context dependent manner. In conclusion, our work supports the functional importance of homorepeats and establishes a basis for the study of other low complexity repeats. Proteins 2017; 85:709–719. © 2016 Wiley Periodicals, Inc.
Reversing the Landauer's erasure: Single‐electron Maxwell's demon operating at the limit of thermodynamic efficiency
Authors: Averin Dmitri V. , Pekola Jukka P.
Published: January 2017

According to Landauer's principle, erasure of information is the only part of a computation process that unavoidably involves energy dissipation. If done reversibly, such an erasure generates the minimal heat of per erased bit of information. The goal of this work is to discuss the actual reversal of the optimal erasure which can serve as the basis for the Maxwell's demon operating with ultimate thermodynamic efficiency as dictated by the second law of thermodynamics. The demon extracts of heat from an equilibrium reservoir at temperature T per one bit of information obtained about the measured system used by the demon. We have analyzed this Maxwell's demon in the situation when it uses a general quantum system with a discrete spectrum of energy levels as its working body. In the case of the effectively two‐level system, which has been realized experimentally based on tunneling of individual electron in a single‐electron box , we also studied and minimized corrections to the ideal reversible operation of the demon. These corrections include, in particular, the non‐adiabatic terms which are described by a version of the classical fluctuation–dissipation theorem. The overall reversibility of the Maxwell's demon requires, beside the reversibility of the intrinsic working body dynamics, the reversibility of the measurement, and feedback processes. The single‐electron demon can, in principle, be made fully reversible by developing a thermodynamically reversible single‐electron charge detector for measurements of the individual charge states of the single‐electron box.
Macro‐invertebrate Community Response to Multi‐annual Hydrological Indicators
Authors: Visser A. , Beevers L. , Patidar S.
Published: January 2017

Flow is widely considered one of the primary drivers of instream ecological response. Increasingly, hydroecological models form the basis of integrated and sustainable approaches to river management, linking flow to ecological response. In doing so, the most ecologically relevant hydrological variables should be selected. Some studies have observed a delayed macro‐invertebrate (ecological) response to these variables (i.e. a cumulative inter‐annual effect, referred to as multi‐annual) in groundwater‐fed rivers. To date, only limited research has been performed investigating this phenomenon. This paper examines the ecological response to multi‐annual flow indicators for a groundwater‐fed river. Relationships between instream ecology and flow were investigated by means of a novel methodological framework developed by integrating statistical data analysis and modelling techniques, such as principal component analysis and multistep regression approaches. Results demonstrated a strong multi‐annual multi‐seasonal effect. Inclusion of additional antecedent flows indicators appears to enhance overall model performance (in some cases, goodness of fit statistics such as the adjusted R‐squared value exceeded 0.6). These results strongly suggest that, in order to understand potential changes to instream ecology arising from changing flow regimes, multi‐annual and multi‐seasonal relationships should be considered in hydroecological modelling. © 2017 The Authors River Research and Applications Published by John Wiley & Sons Ltd.
Core‐Shell Ag@TiO2 Nanocomposites for Low‐Power Blue Laser Enhanced Copper(I) Catalyzed Ullmann Coupling
Authors: Forato Florian , Talebzadeh Somayeh , Bujoli Bruno , Queffélec Clémence , Trammell Scott A. , Knight D. Andrew
Published: January 2017

Silver nanoparticles, stabilized by a titanium dioxide shell, have been prepared and further functionalized using a bidentate 2,2′‐bipyridine ligand end‐capped with a phosphonic acid anchoring group. Then, complexation of the 2,2′‐bipyridine donor ligand with a copper(I) salt was performed. The resulting nanocomposite, while irradiating the Ag plasmon band with a blue laser at 488 nm, was found to be active for the homocoupling Ullmann reaction of iodobenzene and increased yield of 55% vs <1% for the dark reaction was observed.
Si‐, Ge‐, Sn‐Based Anode Materials for Lithium‐Ion Batteries: From Structure Design to Electrochemical Performance
Authors: Li Weihan , Sun Xueliang , Yu Yan
Published: January 2017

As state‐of‐the‐art rechargeable energy‐storage devices, lithium‐ion batteries (LIBs) are widely applied in various areas, such as storage of electrical energy converted from renewable energy and powering portable electronic devices and electric vehicles (EVs). Nevertheless, the energy density and working life of current commercial LIBs cannot satisfy the rapid development of these applications. It is urgently required that the electrochemical performance of LIBs, which is mainly determined by the electroactive electrode materials, is improved. However, commercial graphite‐based anode materials deliver a relatively low theoretical capacity of 372 mA h g−1, severely hindering the increase of the energy density of LIBs. Recently, M‐based anode (M represents Si, Ge, and Sn) materials have attracted great attention due to their high theoretical capacity and reasonable anodic voltage. However, the application of M‐based anode materials is seriously limited by a series of several critical problems, such as poor kinetics and huge volume change on cycling. Here, these fundamental problems leading to poor electrochemical performance are discussed, and a series of reasonable nanostructures for M‐based anodes with improved electrochemical performance is summarized, demonstrating that the dimensional control in structure design plays a critical role for solving these problems.
Concise Review: Induced Pluripotent Stem Cell Research in the Era of Precision Medicine
Authors: Hamazaki Takashi , El Rouby Nihal , Fredette Natalie C. , Santostefano Katherine E. , Terada Naohiro
Published: January 2017

Recent advances in DNA sequencing technologies are revealing how human genetic variations associate with differential health risks, disease susceptibilities, and drug responses. Such information is now expected to help evaluate individual health risks, design personalized health plans and treat patients with precision. It is still challenging, however, to understand how such genetic variations cause the phenotypic alterations in pathobiologies and treatment response. Human induced pluripotent stem cell (iPSC) technologies are emerging as a promising strategy to fill the knowledge gaps between genetic association studies and underlying molecular mechanisms. Breakthroughs in genome editing technologies and continuous improvement in iPSC differentiation techniques are particularly making this research direction more realistic and practical. Pioneering studies have shown that iPSCs derived from a variety of monogenic diseases can faithfully recapitulate disease phenotypes in vitro when differentiated into disease-relevant cell types. It has been shown possible to partially recapitulate disease phenotypes, even with late onset and polygenic diseases. More recently, iPSCs have been shown to validate effects of disease and treatment-related single nucleotide polymorphisms identified through genome wide association analysis. In this review, we will discuss how iPSC research will further contribute to human health in the coming era of precision medicine.
Stromal Cells Act as Guardians for Endothelial Progenitors by Reducing Their Immunogenicity After Co-Transplantation
Authors: Souidi Naima , Stolk Meaghan , Rudeck Juliane , Strunk Dirk , Schallmoser Katharina , Volk Hans-Dieter , Seifert Martina
Published: January 2017

Regeneration of injured tissues requires effective therapeutic strategies supporting vasculogenesis. The lack of instantly available autologous cell sources and immunogenicity of allogeneic endothelial (progenitor) cells limits clinical progress. Based on the immunosuppressive potency of mesenchymal stem/progenitor cells (MSCs), we investigated whether crosstalk between endothelial colony-forming progenitor cells (ECFCs) and MSCs during vasculogenesis could lower allogeneic T cell responses against ECFCs allowing long-term engraftment in vivo. Immunodeficient mice received subcutaneous grafts containing human ECFCs alone, or pairs of human ECFCs/MSCs from the same umbilical cord (UC) to study vasculogenesis in the presence of human leukocyte antigen (HLA)-mismatched human peripheral blood mononuclear cells (PBMCs). In vitro, cell surface marker changes due to interferon gamma (IFNγ) stimulation during ECFC/MSC coculture were determined and further effects on allostimulated T cell proliferation and cytotoxic lysis were measured. IFNγ-induced HLA-DR expression on ECFCs and MSCs, but both cell types had significantly less HLA-DR in cocultures. ECFC-induced T cell proliferation was abolished after MSC coculture as a result of HLA-DR downregulation and indolamin-2,3-dioxygenase activation. Additionally, allospecific CD8+ T cell-mediated lysis of ECFCs was reduced in cocultures. ECFC/MSC coapplication in immunodeficient mice not only promoted the generation of improved blood vessel architecture after 6 weeks, but also reduced intragraft immune cell infiltration and endothelial HLA-DR expression following PBMC reconstitution. Crosstalk between UC-derived ECFCs and MSCs after combined transplantation can lower the risk of ECFC rejection, thus enabling their coapplication for therapeutic vasculogenesis.
Functional responses can unify invasion ecology
Authors: Dick Jaimie T. A. , Alexander Mhairi E. , Ricciardi Anthony , Laverty Ciaran , Downey Paul O. , Xu Meng , Jeschke Jonathan M. , Saul Wolf-Christian , Hill Matthew P. , Wasserman Ryan , Barrios-O’Neill Daniel , Weyl Olaf L. F. , Shaw Richard H.
Published: January 2017

We contend that invasion ecology requires a universal, measurable trait of species and their interactions with resources that predicts key elements of invasibility and ecological impact; here, we advocate that functional responses can help achieve this across taxonomic and trophic groups, among habitats and contexts, and can hence help unify disparate research interests in invasion ecology.
Curbing protest through elite co-optation? Regional protest mobilization by the Russian systemic opposition during the ‘for fair elections’ protests 2011–2012
Authors: Dollbaum Jan Matti
Published: January 2017

How does co-optation of oppositional party elites influence their protest behavior in times of cross-societal protest mobilization? Rational-Choice theories of authoritarian stability postulate that opposition elites receive material incentives in parliaments that motivate them to demobilize their radical supporters, which leads to increased regime stability. Based on a novel dataset, this article examines the protest behavior of the Russian parliamentary opposition parties (the CPRF, the LDPR and JR) and their activists during the protest wave of 2011/12 as a function of each party's co-optation in the regional parliaments. Co-optation is measured by the number of leadership posts that a party holds in the regional legislature. Protest mobilization is captured by (1) the number of protest events organized by each party and (2) the aggregate number of party activists present at protest events per region. The results show clear differences between the parties: Whereas the protest behavior of the communist CPRF is not influenced by regional elite co-optation, the analysis shows negative correlations for the LDPR and JR. The results suggest that co-optation may indeed be effective in reducing protest in contentious times – but that its effect varies for different actors.