bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation and optimization of the metal‐binding properties of a complex ligand for immobilized metal affinity chromatography
Authors: Chen Bin , Li Rong , Li Shiyu , Chen Xiaoli , Yang Kaidi , Chen Guoliang , Ma Xiaoxun
Published: December 2015

The simultaneous determination of two binding parameters for metal ions on an immobilized metal affinity chromatography column was performed by frontal chromatography. In this study, the binding parameters of Cu2+ to l‐glutamic acid were measured, the metal ion‐binding characteristics of the complex ligand were evaluated. The linear correlation coefficients were all greater than 99%, and the relative standard deviations of two binding parameters were 0.58 and 0.059%, respectively. The experiments proved that the frontal chromatography method was accurate, reproducible, and could be used to determine the metal‐binding parameters of the affinity column. The effects of buffer pH, type, and concentration on binding parameters were explored by uniform design experiment. Regression, matching and residual analyses of the models were performed. Meanwhile, the optimum‐binding conditions of Cu2+ on the l‐glutamic acid‐silica column were obtained. Under these binding conditions, observations and regression values of two parameters were similar, and the observation values were the best. The results demonstrated that high intensity metal affinity column could be effectively prepared by measuring and evaluating binding parameters using frontal chromatography combined with a uniform design experiment. The present work provided a new mode for evaluating and preparing immobilized metal affinity column with good metal‐binding behaviors.
Determination of trace levels of triazines in corn matrices by bar adsorptive microextraction with a molecularly imprinted polymer
Authors: Andrade Felipe Nascimento , Ide Alessandra Honjo , Neng Nuno da Rosa , Lanças Fernando Mauro , Nogueira José Manuel Florêncio
Published: December 2015

This manuscript addresses the determination of triazines (ametryn, atrazine, simazine, and terbutryn) in corn matrices using bar adsorptive microextraction coated with a selective molecularly imprinted polymer phase following microliquid desorption and high‐performance liquid chromatography with diode array detection. The molecularly imprinted polymer was synthesized using atrazine as a template and methacrylic acid as a functional monomer. Assays performed in 25 mL of ultrapure water samples spiked at 8.0 μg/L yielded 80–120 % recoveries under the evaluated experimental conditions. The method showed an accuracy (0.2 < bias < 17.9%), precision (relative standard deviation <17.4%), convenient detection (0.2 μg/L), and quantification (0.7 μg/L) limits, as well as linear dynamic ranges (0.8–24.0 μg/L) with remarkable determination coefficients (R2 > 0.9926). The proposed analytical method was applied to monitor triazines in three types of corn matrices using the standard addition methodology. Experiments performed in corn samples spiked with triazines at the trace level (8.0 μg/kg of each analyte) gave rise to recoveries (81.0–119.4%) with good reproducibility and robustness. The proposed methodology is also easy to implement and showed to be a good analytical alternative to monitor triazines in complex matrices, when compared with other sorption‐based microextraction techniques.
Investigations in Fundamental and Applied Polymer Mechanochemistry
Authors: Larsen Michael B. , Boydston Andrew J.
Published: December 2015

The field of polymer mechanochemistry has experienced rapid growth over the past decade, propelled largely by the development of force‐activated functional groups (mechanophores) and polymer structure‐reactivity principles for mechanochemical transduction. In addition to fundamental guidelines for converting mechanical input into chemical output, there has also been increasing focus toward the application of polymer mechanochemistry for specific functions, materials, and devices. These endeavors are made possible by multidisciplinary approaches involving designer polymer synthesis, computational modeling and design, and different fields of engineering. Described herein are contributions from our group on the development of flex activated mechanophores for small molecule release and star polymer mechanochemistry, as well as collaborative efforts toward mechanochemically triggered depolymerizations and 3D printed mechanochromic materials.

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An Exploratory Study of the Experience of Ageing with Ankylosing Spondylitis: ‘Same Backdrop but a Changing Scene’
Authors: Martindale J. , Kashefi Elham , Goodacre L.
Published: December 2015

Objectives

People are living longer with a long‐term health condition. Our aim was to develop a greater understanding of the experience and needs of people as they age with ankylosing spondylitis (AS).

Methods

Ethical approval was obtained for six focus groups, with participants over 60 years of age, to explore experiences through peer group discussion. The groups were recorded and transcribed. Transcripts were coded and a thematic analysis was conducted using NVIVO 10.

Results

Four women and 28 men, with an average age of 68 (range 60–83) years, consented to participate. Analysis identified a central organizing concept, ‘same backdrop but a changing scene’, which conceptualizes the continued impact of AS set against a backdrop of people transitioning into a new phase of their lives and facing differing challenges. Five themes underpin this concept: ‘it doesn't go away’ (AS remains active with continuing functional and symptomatic challenges); ‘wheels fall off after 60’ (perceptions of disease progression within the context of ‘normal ageing’); ‘keep on pushing, keep on doing’ (challenges of remaining active and motivated); ‘living a fulfilling life’ (actively engaging with life) and a ‘price to pay’ (significant psychological, physical and financial consequences on participants and their families).

Conclusions

As people living with AS make the transition into retirement, many aspire to live active lives while facing new challenges in relation to their lifestyles and priorities. There is a need to offer tailored interventions to enable older people to remain active and continue to lead the lives they choose within the context of an active and often debilitating condition. Copyright © 2015 John Wiley & Sons, Ltd.
Effect of continuous positive airway pressure on nocturnal urine production in patients with obstructive sleep apnea syndrome
Authors: Miyazato Minoru , Tohyama Kazuyo , Touyama Masato , Nakamura Hiroshi , Oshiro Takuma , Ueda Shinichiro , Saito Seiichi
Published: December 2015

Aim

The aim of this study was to identify the clinical features of patients with obstructive sleep apnea syndrome (OSAS) and investigate the impact of continuous positive airway pressure (CPAP) treatment on nocturnal urine volume.

Materials and Methods

This study enrolled 53 patients with moderate‐to‐severe OSAS and an apnea‐hypoxia index of >20/hr. Data were collected on serum brain natriuretic peptide (BNP) level, International Prostate Symptom Score‐Quality of Life (IPSS‐QOL) score, Overactive Bladder Symptom Score (OABSS), International Consultation on Incontinence Modular Questionnaire‐Nocturia QOL (ICIQ‐NQOL) score, Epworth Sleepiness Scale (ESS) score, and the frequency volume chart. Only patients who continued CPAP treatment for 3 months were included in the analysis.

Results

In total, 40 patients (33 men and 7 women) completed the study (75.5%). The mean age was 56.9 years. The night‐time frequency to void was significantly decreased from 2.1 to 1.2 after CPAP treatment (P < 0.01). The mean scores as assessed by ESS, IPSS‐QOL, OABSS, and ICIQ‐NQOL significantly improved after CPAP (P < 0.01). The mean diastolic blood pressure significantly decreased after CPAP treatment. However, there was no significant change in the BNP level before and after CPAP treatment. In the frequency volume chart, hours of undisturbed sleep, total nocturnal voided volume, and nocturnal polyuria index significantly improved after CPAP treatment (P < 0.05). However, 24‐hr voided volume and mean voided volume during night‐time did not change after CPAP treatment.

Conclusion

CPAP treatment decreases night‐time urinary frequency by reducing nocturnal urine production and improves QOL in patients with OSAS. Neurourol. Urodynam. 36:376–379, 2017. © 2015 Wiley Periodicals, Inc.
Pelvic floor muscle functions are improved after successful transobturator vaginal mesh procedures
Authors: Huang Wen‐Chen , Yang Shwu‐Huey , Yang Jenn‐Ming
Published: December 2015

Aims

To explore functional changes of pelvic floor muscle (PFM) after successful Perigee procedures.

Methods

We retrospectively analyzed information from 145 women having achieved anatomic success, defined as <stage II cystocele according to the pelvic organ prolapse quantification (POP‐Q) system. The investigated data included results from the POP‐Q system and four‐dimensional ultrasound at the preoperative and 12‐month postoperative evaluations. The involuntary and voluntary PFM functions were, respectively, investigated during coughing and squeezing using the ultrasound parameters of the bladder neck distance (BND), bladder neck angle (BNA), genitohiatal distance (GHD), and genitohiatal angle.

Results

Postoperatively more women displayed normal involuntary PFM function in maintaining a stable bladder neck (preoperative vs. postoperative: 4.8% vs. 22.8%, P < 0.001) and genitohiatal (preoperative vs. postoperative: 16.6% vs. 30.3%, P = 0.008) locations upon coughing and could perform voluntary PFM contractions (preoperative vs. postoperative: 49.7% vs. 64.1%, P = 0.018). Compared with preoperative manifestations, less caudal displacement of the bladder neck indicated by smaller ranges of dynamic changes in BNA following coughing (preoperative vs. postoperative: 28° vs. 12°, P < 0.001), more cranial movement of the bladder neck indicated by larger values of changes in BND following squeezing (−0.26 vs. 0.06 cm, P < 0.001), and less reduction of genitohiatal size indicated by larger values of changes in GHD following squeezing (preoperative vs. postoperative: −0.95 vs. −0.63 cm, P = 0.027) were demonstrated postoperatively.

Conclusions

Involuntary and voluntary PFM functions are improved after successful Perigee procedures. Neurourol. Urodynam. 36:380–384, 2017. © 2015 Wiley Periodicals, Inc.
Slow‐release nanopolymeric biodegradable composites holding doxorubicin and evaluation its antiproliferative potency on cancer
Authors: Helaly Fahima M. , El Nashar Doaa E. , Khalaf Aman I. , Abdelhamid Hala F. , Wietrzyk Joanna , Psurski Mateusz , Soliman Abdelmohsen
Published: December 2015

This work represents the functionalization of nanoscale biodegradable polymer and controls its sustained release rate for long time period. The polymer was synthesized by free radical polymerization reaction. Starch cellulose acetate co‐acrylate (SCAA) polymer was prepared and loaded with doxorubicin drug. The polymer before and after loading was characterized by Fourier‐transform infrared spectroscopy, gel permeation chromatography, and high‐resolution transmission electron microscopy. The release‐rate study illustrated good property through sustained release and extended to ∼65 days. The antiproliferative effect of doxorubicin slowly released from the prepared nanobiodegradable polymer illustrated growth inhibition potency toward human colon and liver cancer cell lines LoVo and HEPG2. POLYM. COMPOS., 38:E34–E41, 2017. © 2015 Society of Plastics Engineers
Predicted Anisotropic Thermal Conductivity for Crystalline 1,3,5‐Triamino‐2,4,6‐trinitobenzene (TATB): Temperature and Pressure Dependence and Sensitivity to Intramolecular Force Field Terms
Authors: Kroonblawd Matthew P. , Sewell Thomas D.
Published: December 2015

The anisotropic thermal conductivity of the layered molecular crystal 1,3,5‐triamino‐2,4,6‐trinitrobenzene (TATB), an insensitive secondary high explosive, is determined using classical molecular dynamics on the P=0.0 GPa isobar for temperatures 200 K≤T≤700 K and on the T=300 K isotherm for pressures 0.0 GPa≤P≤2.5 GPa. Sensitivity of the predicted (300 K, 0.0 GPa) conductivity to intramolecular terms in the force field is investigated. Two conduction directions are considered, one nominally within and the other exactly perpendicular to the stacked planar single‐molecule‐thick layers comprising the TATB crystal. The thermal conductivity λ(T,P) along both directions is found to decrease approximately as λ∝1/T with increasing temperature and increase approximately linearly λ ∝ T with increasing pressure. The temperature dependence is found to be highly anisotropic with nearly twice as large a reduction in absolute conductivity within the molecular layers (Δλ=−0.67 W m−1 K−1) compared to between them (Δλ=−0.35 W m−1 K−1). Anisotropy in the conductivity is predicted to decrease with increasing temperature; the P=0.0 GPa conductivity is 68 % greater within the layers than between them at 200 K, but only 49 % greater at 700 K. The pressure dependence is also anisotropic, with a 51 % and 76 % increase in conductivity within and between the layers, respectively. Predicted values for the conductivity are found to differ by less than 12 % for several instructive modifications to the intramolecular force field. Completely eliminating high‐frequency NH bond vibrations using the SHAKE algorithm leads to an isotropic reduction in the conductivity that scales as the corresponding reduction in the classical heat capacity, indicating that optical phonons are likely significant contributors to the total conductivity. Replacing harmonic bond potential energy functions with anharmonic Morse functions results in an isotropic ≈6 % reduction that is likely due to stronger phonon‐phonon coupling and corresponding reduction in the phonon mean free path.
A visualization method measuring the performance of biomarkers for guiding treatment decisions
Authors: Yang Hui , Tang Rui , Hale Mike , Huang Jing
Published: December 2015

Biomarkers that predict efficacy and safety for a given drug therapy become increasingly important for treatment strategy and drug evaluation in personalized medicine. Methodology for appropriately identifying and validating such biomarkers is critically needed, although it is very challenging to develop, especially in trials of terminal diseases with survival endpoints. The marker‐by‐treatment predictiveness curve serves this need by visualizing the treatment effect on survival as a function of biomarker for each treatment. In this article, we propose the weighted predictiveness curve (WPC). Based on the nature of the data, it generates predictiveness curves by utilizing either parametric or nonparametric approaches. Especially for nonparametric predictiveness curves, by incorporating local assessment techniques, it requires minimum model assumptions and provides great flexibility to visualize the marker‐by‐treatment relationship. WPC can be used to compare biomarkers and identify the one with the highest potential impact. Equally important, by simultaneously viewing several treatment‐specific predictiveness curves across the biomarker range, WPC can also guide the biomarker‐based treatment regimens. Simulations representing various scenarios are employed to evaluate the performance of WPC. Application on a well‐known liver cirrhosis trial sheds new light on the data and leads to discovery of novel patterns of treatment biomarker interactions. Copyright © 2015 John Wiley & Sons, Ltd.
New York State Public Health System Response to Hurricane Sandy: An Analysis of Emergency Reports
Authors: Shipp Hilts Asante , Mack Stephanie , Eidson Millicent , Nguyen Trang , Birkhead Guthrie S.
Published: December 2015

Objective

Analyzing Hurricane Sandy emergency reports to assess the New York State (NYS) public health system response will help inform and improve future disaster preparedness and response.

Methods

Qualitative analysis of NYS Department of Health (NYSDOH) and Nassau and Suffolk County local health department (LHD) emergency reports was conducted. Three after-action reports and 48 situation reports were reviewed, grouped by key words and sorted into 16 Public Health Preparedness Capabilities. Within each capability, key words were labeled as strengths, challenges, or recommendations.

Results

The NYSDOH capability most cited as a strength was successful emergency operations coordination, eg, interagency conference calls (27.4% of 1681 strengths). The most cited challenge was environmental health protection, eg, mold and oil spills (28% of 706 challenges). The LHD capability most cited both as a strength (46.7% of 30 strengths) and as a challenge (32.5% of 123 challenges) was emergency operations coordination. Strengths were exemplified by sharing local resources and challenges by insufficient memorandums of understanding for coordination.

Conclusions

Post-disaster emergency reports should be systematically reviewed to highlight both successes and areas for improvement. Future studies should prioritize collecting feedback from a wider spectrum of public health and service provider staff for planning of preparedness and response activities. (Disaster Med Public Health Preparedness. 2015;10:308–313)
Preparing International Relief Workers for Health Care in the Field: An Evaluation of Organizational Practices
Authors: Moresky Rachel T. , Eliades M. James , Bhimani M.A. , Bunney E. Bradshaw , VanRooyen Michael J.
Published: December 2015

The growth of the humanitarian aid industry has led to the proliferation of relief programs and the rapid rise in the number of relief personnel working in the field. One major necessity in developing successful international programs is appropriately trained field personnel. The purpose of this study was to evaluate the educational practice and training methods for field workers by non-government organizations (NGO).

Of the 53 organizations surveyed, 64% responded that they sent health care workers to acute human emergencies. A majority of organizations, 31/53 (59%), used manuals as the primary method of training for workers before going into the field. Eighty-five percent of organizations (45/53) supplied their workers with trip briefings from prior personnel before going into the field, and 91% (48/53) had an on-site coordinator. Only 34% (18/53) provided classroom teaching or orientation prior to departure. The average number of months spent by workers abroad was ≤1 for nearly half (49%) of the NGOs. Only 34% (18/53) of the NGOs required that personnel had previous international experience.

Training of humanitarian workers varies significantly between nongovernmental organizations. Lack of standardization in training programs and wide variation of provider preparedness indicates the need by NGOs for enhanced training for field personnel.
Shame and Psychopathology
Authors: Pallanti Stefano , Quercioli Leonardo
Published: December 2015

The origins of the word “shame” recall the concept of the infraction of integrity both as scandal and as individualization. The human experience of shame stretches along a continuum from modesty to disabling interpersonal terror. Unlike other basic affects, its emergence is a fundamental moment in the process of self-awareness and self-object differentiation. Neglected by psychiatry because it was regarded as a moral concept, today it is possible to hypothesize that it has a biologic basis that one can attempt to describe in terms of corticothalamic pathways. In this respect, like other affects, it could be considered as a cognitive shortcut to activate specific and evolutionally useful behavioral patterns, such as concealment or a request for affiliation. It is fairly ubiquitous in psychopathology, but is clinically much more structured in its abnormal expressions in anxiety disorders, particularly social phobia, obsessive-compulsive disorder, eating disorders, body dysmorphic disorder, and even in bipolar mood disorder. In schizophrenia it has been described as being one stage in the construction of delusion. Its presence is connected to interpersonal relationship (altruism) though it seems absent in autism. The assessment of shame experiences in psychiatric patients could be useful for both pharmacological and psychotherapeutic strategies, and could provide a categorization of a new psychopathology based on abnormal affects.
A proposal of the proteome before the last universal common ancestor (LUCA)
Authors: de Farias Sávio Torres , Rêgo Thais Gaudêncio , José Marco V
Published: December 2015

The search for understanding the biological nature of the last universal common ancestor (LUCA) has been a theoretical challenge and has sparked intense debate in the scientific community. We reconstructed the ancestral sequences of tRNAs in order to test the hypothesis that these molecules originated the first genes. The results showed that the proteome before LUCA may have been composed of basal energy metabolism, namely, compounds with three carbons in the glycolytic pathway, which operated as a distribution centre of substrates for the development of metabolic pathways of nucleotides, lipids and amino acids. Thus, we present a proposal for metabolism in organisms before LUCA that was the initial core for the assembly of further metabolic pathways.
Cloud Overlap Observations Put Simulations to the Test
Authors: Stanley Sarah
Published: December 2015

Fine-scale simulations of cumulus cloud layers could help improve weather and climate models.
Socs1 and Socs3 degrades Traf6 via polyubiquitination in LPS-induced acute necrotizing pancreatitis
Authors: Zhou X , Liu Z , Cheng X , Zheng Y , Zeng F , He Y
Published: December 2015

Mechanisms involved in inflammatory development during acute pancreatitis (AP) are largely vague, especially in the transformation of acute edematous pancreatitis (AEP) into acute necrotizing pancreatitis (ANP). This current study aims to investigate the functions of Traf6 in different AP models in vitro and in vivo, and to identify the possible regulatory mechanism in the progression of inflammation from mild to severe. Our data revealed that the level of Traf6 expression was significantly increased in the mild AP induced by caerulein, and the upregulation of Traf6 played a protective role in acinar cells against caerulein-induced apoptosis. In contrast, only Traf6 protein but not mRNA was downregulated in the severe ANP induced by combination treatment of caerulein and LPS. Mechanistic studies showed that LPS upregulated the levels of Socs1 and Socs3 expressions in acinar cells, Socs1 and Socs3 interacted Traf6 directly and degraded Traf6 protein via polyubiquitination, thereby counteracted the protective function of Traf6. In vivo study further showed that combination treatment of caerulein and LPS failed to induce an ANP model in the TLR4 knockout mice, and the level of Traf6 expression in the pancreatic tissues remained the same as that from the acute edematous pancreatitis (AEP) mouse. Taken together, our study reveals that Traf6 functioned as a protective factor in the progression of AP, and LPS-induced Socs1 and Socs3 exacerbate mild AP to severe AP, which provides evidence for developing a new therapeutic target to combat AP.
Hibernation in the pygmy slow loris (Nycticebus pygmaeus): multiday torpor in primates is not restricted to Madagascar
Authors: Ruf Thomas , Streicher Ulrike , Stalder Gabrielle L. , Nadler Tilo , Walzer Chris
Published: December 2015

Hibernation and short daily torpor are states of energy conservation with reduced metabolism and body temperature. Both hibernation, also called multiday torpor and daily torpor are common among mammals and occur in at least 11 orders. Within the primates, there is a peculiar situation, because to date torpor has been almost exclusively reported for Malagasy lemurs. The single exception is the African lesser bushbaby, which is capable of daily torpor, but uses it only under extremely adverse conditions. For true hibernation, the geographical restriction was absolute. No primate outside of Madagascar was previously known to hibernate. Since hibernation is commonly viewed as an ancient, plesiomorphic trait, theoretically this could mean that hibernation as an overwintering strategy was lost in all other primates in mainland Africa, Asia and the Americas. However, we hypothesized that a good candidate species for the use of hibernation, outside of Madagascar should be the pygmy slow loris (Nycticebus pygmaeus), a small primate inhabiting tropical forests. Here, we show that pygmy slow lorises exposed to natural climatic conditions in northern Vietnam during winter indeed undergo torpor lasting up to 63 h, that is, hibernation. Thus, hibernation has been retained in at least one primate outside of Madagascar.
Systematic unravelling of the biosynthesis of poly (L-diaminopropionic acid) in Streptomyces albulus PD-1
Authors: Xu Zhaoxian , Sun Zhuzhen , Li Sha , Xu Zheng , Cao Changhong , Xu Zongqi , Feng Xiaohai , Xu Hong
Published: December 2015

Poly(L-diaminopropionic acid) (PDAP) is one of the four homopoly(amino acid)s that have been discovered in nature. However, the molecular mechanism of PDAP biosynthesis has yet to be described. In this work, the general layout of the PDAP biosynthetic pathway is characterised in Streptomyces albulus PD-1 by genome mining, gene disruption, heterologous expression and in vitro feeding experiments. As a result, L-diaminopropionic acid (L-DAP), which is the monomer of PDAP, is shown to be jointly synthesised by two protein homologues of cysteine synthetase and ornithine cyclodeaminase. Then, L-DAP is assembled into PDAP by a novel nonribosomal peptide synthetase (NRPS) with classical adenylation and peptidyl carrier protein domains. However, instead of the traditional condensation or thioesterase domain of NRPSs, this NRPS has seven transmembrane domains surrounding three tandem soluble domains at the C-terminus. As far as we know, this novel single-module NRPS structure has only been reported in poly(ε-L-lysine) synthetase. The similar NRPS structure of PDAP synthetase and poly(ε-L-lysine) synthetase may be a common characteristic of homopoly(amino acid)s synthetases. In this case, we may discover and/or design more homopoly(amino acid)s by mining this kind of novel NRPS structure in the future.
Flower-like PEGylated MoS2 nanoflakes for near-infrared photothermal cancer therapy
Authors: Feng Wei , Chen Liang , Qin Ming , Zhou Xiaojun , Zhang Qianqian , Miao Yingke , Qiu Kexin , Zhang Yanzhong , He Chuanglong
Published: December 2015

Photothermal cancer therapy has attracted considerable interest for cancer treatment in recent years, but the effective photothermal agents remain to be explored before this strategy can be applied clinically. In this study, we therefore develop flower-like molybdenum disulfide (MoS2) nanoflakes and investigate their potential for photothermal ablation of cancer cells. MoS2 nanoflakes are synthesized via a facile hydrothermal method and then modified with lipoic acid-terminated polyethylene glycol (LA-PEG), endowing the obtained nanoflakes with high colloidal stability and very low cytotoxicity. Upon irradiation with near infrared (NIR) laser at 808 nm, the nanoflakes showed powerful ability of inducing higher temperature, good photothermal stability and high photothermal conversion efficiency. The in vitro photothermal effects of MoS2-PEG nanoflakes with different concentrations were also evaluated under various power densities of NIR 808-nm laser irradiation and the results indicated that an effective photothermal killing of cancer cells could be achieved by a low concentration of nanoflakes under a low power NIR 808-nm laser irradiation. Furthermore, cancer cell in vivo could be efficiently destroyed via the photothermal effect of MoS2-PEG nanoflakes under the irradiation. These results thus suggest that the MoS2-PEG nanoflakes would be as promising photothermal agents for future photothermal cancer therapy.
Cooperation in group-structured populations with two layers of interactions
Authors: Zhang Yanling , Fu Feng , Chen Xiaojie , Xie Guangming , Wang Long
Published: December 2015

Recently there has been a growing interest in studying multiplex networks where individuals are structured in multiple network layers. Previous agent-based simulations of games on multiplex networks reveal rich dynamics arising from interdependency of interactions along each network layer, yet there is little known about analytical conditions for cooperation to evolve thereof. Here we aim to tackle this issue by calculating the evolutionary dynamics of cooperation in group-structured populations with two layers of interactions. In our model, an individual is engaged in two layers of group interactions simultaneously and uses unrelated strategies across layers. Evolutionary competition of individuals is determined by the total payoffs accrued from two layers of interactions. We also consider migration which allows individuals to move to a new group within each layer. An approach combining the coalescence theory with the theory of random walks is established to overcome the analytical difficulty upon local migration. We obtain the exact results for all “isotropic” migration patterns, particularly for migration tuned with varying ranges. When the two layers use one game, the optimal migration ranges are proved identical across layers and become smaller as the migration probability grows.
When cells divide: Label-free multimodal spectral imaging for exploratory molecular investigation of living cells during cytokinesis
Authors: Hsu Jen-Fang , Hsieh Pei-Ying , Hsu Hsin-Yun , Shigeto Shinsuke
Published: December 2015

In vivo, molecular-level investigation of cytokinesis, the climax of the cell cycle, not only deepens our understanding of how life continues, but it will also open up new possibilities of diagnosis/prognosis of cancer cells. Although fluorescence-based methods have been widely employed to address this challenge, they require a fluorophore to be designed for a specific known biomolecule and introduced into the cell. Here, we present a label-free spectral imaging approach based on multivariate curve resolution analysis of Raman hyperspectral data that enables exploratory untargeted studies of mammalian cell cytokinesis. We derived intrinsic vibrational spectra and intracellular distributions of major biomolecular components (lipids and proteins) in dividing and nondividing human colon cancer cells. In addition, we discovered an unusual autofluorescent lipid component that appears predominantly in the vicinity of the cleavage furrow during cytokinesis. This autofluorescence signal could be utilized as an endogenous probe for monitoring and visualizing cytokinesis in vivo.
How silicene on Ag(111) oxidizes: microscopic mechanism of the reaction of O2 with silicene
Authors: Morishita Tetsuya , Spencer Michelle J.S.
Published: December 2015

We demonstrate, using first-principles molecular-dynamics simulations, that oxidation of silicene can easily take place either at low or high oxygen doses, which importantly helps clarify previous inconsistent reports on the oxidation of silicene on the Ag(111) substrate. We show that, while the energy barrier for an O2 molecule reacting with a Si atom strongly depends on the position and orientation of the molecule, the O2 molecule immediately dissociates and forms an Si-O-Si configuration once it finds a barrier-less chemisorption pathway around an outer Si atom of the silicene overlayer. A synergistic effect between the molecular dissociation and subsequent structural rearrangements is found to accelerate the oxidation process at a high oxygen dose. This effect also enhances self-organized formation of sp3-like tetrahedral configurations (consisting of Si and O atoms), which results in collapse of the two-dimensional silicene structure and its exfoliation from the substrate. We also find that the electronic properties of the silicene can be significantly altered by oxidation. The present findings suggest that low flux and low temperature of the oxygen gas are key to controlling oxidation of silicene.
Upregulation of KSRP by miR-27b provides IFN-γ-induced post-transcriptional regulation of CX3CL1 in liver epithelial cells
Authors: Xia Zijie , Lu Yajing , Li Xiaoqing , Mao Tiebo , Chen Xian-Ming , Zhou Rui
Published: December 2015

Aberrant cellular responses to pro-inflammatory cytokines, such as IFN-γ, are pathogenic features in many chronic inflammatory diseases. A variety of feedback regulatory pathways have evolved to prevent an inappropriate cellular reaction to these pro-inflammatory cytokines. CX3CL1 is a unique chemokine and plays an important role in chronic liver diseases. We report here that IFN-γ stimulation induces a transient CX3CL1 production in liver epithelial cells (i.e., hepatocytes and biliary epithelial cells). This transient CX3CL1 production is accompanied with a destabilization of CX3CL1 mRNA associated with the induction of the KH-type splicing regulatory protein (KSRP). IFN-γ treatment of liver epithelial cells decreases expression level of miR-27b, a miRNA that targets the 3′ untranslated region of KSRP mRNA resulting in translational suppression. Induction of KSRP following IFN-γ stimulation depends on the downregulation of miR-27b. Functional manipulation of KSRP or miR-27b caused reciprocal alterations in CX3CL1 mRNA stability in liver epithelial cells. Moreover, transfection of miR-27b precursor influences CX3CL1-associated chemotaxis effects of biliary epithelial cells to Jurkat T cells. These findings suggest that miR-27b-mediated post-transcriptional suppression controls the expression of KSRP in liver epithelial cells and upregulation of KSRP destabilizes CX3CL1 mRNA, providing fine-tuning of cellular inflammatory reactions in response to IFN-γ stimulation.
Hierarchical One-Dimensional Ammonium Nickel Phosphate Microrods for High-Performance Pseudocapacitors
Authors: Raju Kumar , Ozoemena Kenneth I.
Published: December 2015

High-performance electrochemical capacitors will drive the next-generation portable, flexible and wearable electronics. Unlike the conventional all-carbon supercapacitors (electric double layer capacitors, EDLC) with high power but poor energy density, pseudocapacitors capitalize the high energy density inherent to reversible redox reactions and provide a facile means to enhancing the energy ratings of supercapacitors. The high length-to-diameter ratio and anisotropic character of 1-D architecture makes them suitable for use in energy storage. For the first time, we report 1-D microrod structures (~ 36 nm width) of ammonium nickel phosphate hydrate (ANPmr) as a pseudocapacitor with high energy rating and power handling. To confirm the data, the ANPmr-based pseudocapacitor was subjected to various configurations (i.e., half-cell, symmetric, asymmetric and flexible all-solid-state) and in each case it gave excellent values compared to any accessible literature to date. We clearly demonstrate that a flexible all-solid-state ANPmr-based pseudocapacitor achieved high areal capacitance of 66 mF cm−2 with extra-ordinary energy (21.2 mWh cm−2) and power (12.7 mW cm−2) densities. This work opens doors for a facile, robust and scalable preparation strategy for low-cost, earth-abundant electrode materials for high-performance pseudocapacitors.
Ex vivo multiscale quantitation of skin biomechanics in wild-type and genetically-modified mice using multiphoton microscopy
Authors: Bancelin Stéphane , Lynch Barbara , Bonod-Bidaud Christelle , Ducourthial Guillaume , Psilodimitrakopoulos Sotiris , Dokládal Petr , Allain Jean-Marc , Schanne-Klein Marie-Claire , Ruggiero Florence
Published: December 2015

Soft connective tissues such as skin, tendon or cornea are made of about 90% of extracellular matrix proteins, fibrillar collagens being the major components. Decreased or aberrant collagen synthesis generally results in defective tissue mechanical properties as the classic form of Elhers-Danlos syndrome (cEDS). This connective tissue disorder is caused by mutations in collagen V genes and is mainly characterized by skin hyperextensibility. To investigate the relationship between the microstructure of normal and diseased skins and their macroscopic mechanical properties, we imaged and quantified the microstructure of dermis of ex vivo murine skin biopsies during uniaxial mechanical assay using multiphoton microscopy. We used two genetically-modified mouse lines for collagen V: a mouse model for cEDS harboring a Col5a2 deletion (a.k.a. pN allele) and the transgenic K14-COL5A1 mice which overexpress the human COL5A1 gene in skin. We showed that in normal skin, the collagen fibers continuously align with stretch, generating the observed increase in mechanical stress. Moreover, dermis from both transgenic lines exhibited altered collagen reorganization upon traction, which could be linked to microstructural modifications. These findings show that our multiscale approach provides new crucial information on the biomechanics of dermis that can be extended to all collagen-rich soft tissues.
Sec13 Regulates Expression of Specific Immune Factors Involved in Inflammation In Vivo
Authors: Moreira Thais G. , Zhang Liang , Shaulov Lihi , Harel Amnon , Kuss Sharon K. , Williams Jessica , Shelton John , Somatilaka Bandarigoda , Seemann Joachim , Yang Jue , Sakthivel Ramanavelan , Nussenzveig Daniel R. , Faria Ana M. C. , Fontoura Beatriz M. A.
Published: December 2015

The Sec13 protein functions in various intracellular compartments including the nuclear pore complex, COPII-coated vesicles and inside the nucleus as a transcription regulator. Here we developed a mouse model that expresses low levels of Sec13 (Sec13H/−) to assess its functions in vivo, as Sec13 knockout is lethal. These Sec13 mutant mice did not present gross defects in anatomy and physiology. However, the reduced levels of Sec13 in vivo yielded specific immunological defects. In particular, these Sec13 mutant mice showed low levels of MHC I and II expressed by macrophages, low levels of INF-γ and IL-6 expressed by stimulated T cells and low frequencies of splenic IFN-γ+CD8+ T cells. In contrast, the levels of soluble and membrane-bound TGF-β as well as serum immunoglobulin production are high in these mice. Furthermore, frequencies of CD19+CD5-CD95+ and CD19+CD5-IL-4+ B cells were diminished in Sec13H/− mice. Upon stimulation or immunization, some of the defects observed in the naïve mutant mice were compensated. However, TGF-β expression remained high suggesting that Sec13 is a negative modulator of TGF-β expression and of its immunosuppressive functions on certain immune cells. In sum, Sec13 regulates specific expression of immune factors with key functions in inflammation.
Plasmon-gating photoluminescence in graphene/GeSi quantum dots hybrid structures
Authors: Chen Yulu , Wu Qiong , Ma Yingjie , Liu Tao , Fan Yongliang , Yang Xinju , Zhong Zhenyang , Xu Fei , Lu Jianping , Jiang Zuimin
Published: December 2015

The ability to control light-matter interaction is central to several potential applications in lasing, sensing and communication. Graphene plasmons provide a way of strongly enhancing the interaction and realizing ultrathin optoelectronic devices. Here, we find that photoluminescence (PL) intensities of the graphene/GeSi quantum dots hybrid structures are saturated and quenched under positive and negative voltages at the excitation of 325 nm, respectively. A mechanism called plasmon-gating effect is proposed to reveal the PL dependence of the hybrid structures on the external electric field. On the contrary, the PL intensities at the excitation of 405 and 795 nm of the hybrid structures are quenched due to the charge transfer by tuning the Fermi level of graphene or the blocking of the excitons recombination by excitons separation effect. The results also provide an evidence for the charge transfer mechanism. The plasmon gating effect on the PL provides a new way to control the optical properties of graphene/QD hybrid structures.
Accelerated 2D magnetic resonance spectroscopy of single spins using matrix completion
Authors: Scheuer Jochen , Stark Alexander , Kost Matthias , Plenio Martin B. , Naydenov Boris , Jelezko Fedor
Published: December 2015

Two dimensional nuclear magnetic resonance (NMR) spectroscopy is one of the major tools for analysing the chemical structure of organic molecules and proteins. Despite its power, this technique requires long measurement times, which, particularly in the recently emerging diamond based single molecule NMR, limits its application to stable samples. Here we demonstrate a method which allows to obtain the spectrum by collecting only a small fraction of the experimental data. Our method is based on matrix completion which can recover the full spectral information from randomly sampled data points. We confirm experimentally the applicability of this technique by performing two dimensional electron spin echo envelope modulation (ESEEM) experiments on a two spin system consisting of a single nitrogen vacancy (NV) centre in diamond coupled to a single13C nuclear spin. The signal to noise ratio of the recovered 2D spectrum is compared to the Fourier transform of randomly subsampled data, where we observe a strong suppression of the noise when the matrix completion algorithm is applied. We show that the peaks in the spectrum can be obtained with only 10% of the total number of the data points. We believe that our results reported here can find an application in all types of two dimensional spectroscopy, as long as the measured matrices have a low rank.
Investigation of reactions between trace gases and functional CuO nanospheres and octahedrons using NEXAFS-TXM imaging
Authors: Henzler Katja , Heilemann Axel , Kneer Janosch , Guttmann Peter , Jia He , Bartsch Eckhard , Lu Yan , Palzer Stefan
Published: December 2015

In order to take full advantage of novel functional materials in the next generation of sensorial devices scalable processes for their fabrication and utilization are of great importance. Also understanding the processes lending the properties to those materials is essential. Among the most sought-after sensor applications are low-cost, highly sensitive and selective metal oxide based gas sensors. Yet, the surface reactions responsible for provoking a change in the electrical behavior of gas sensitive layers are insufficiently comprehended. Here, we have used near-edge x-ray absorption fine structure spectroscopy in combination with x-ray microscopy (NEXAFS-TXM) forex-situmeasurements, in order to reveal the hydrogen sulfide induced processes at the surface of copper oxide nanoparticles, which are ultimately responsible for triggering a percolation phase transition. For the first time these measurements allow the imaging of trace gas induced reactions and the effect they have on the chemical composition of the metal oxide surface and bulk. This makes the new technique suitable for elucidating adsorption processesin-situand under real operating conditions.
Three-Dimensional Assignment of the Structures of Atomic Clusters: an Example of Au8M (M=Si, Ge, Sn) Anion Clusters
Authors: Liu Yi-Rong , Huang Teng , Gai Yan-Bo , Zhang Yang , Feng Ya-Juan , Huang Wei
Published: December 2015

Identification of different isomer structures of atomic and molecular clusters has long been a challenging task in the field of cluster science. Here we present a three-dimensional (3D) assignment method, combining the energy (1D) and simulated (2D) spectra to assure the assignment of the global minimum structure. This method is more accurate and convenient than traditional methods, which only consider the total energy and first vertical detachment energies (VDEs) of anion clusters. There are two prerequisites when the 3D assignment method is ultilized. First, a reliable global minimum search algorithm is necessary to explore enough valleys on the potential energy surface. Second, trustworthy simulated spectra are necessary, that is to say, spectra that are in quantitative agreement. In this paper, we demonstrate the validity of the 3D assignment method using Au8M− (M = Si, Ge, Sn) systems. Results from this study indicate that the global minimum structures of Au8Ge− and Au8Sn− clusters are different from those described in previous studies.
Preclinical detection of infectivity and disease-specific PrP in blood throughout the incubation period of prion disease
Authors: Sawyer Elizabeth B. , Edgeworth Julie Ann , Thomas Claire , Collinge John , Jackson Graham S.
Published: December 2015

Variant Creutzfeldt-Jakob disease (vCJD) is a fatal neurodegenerative disorder characterised by accumulation of pathological isoforms of the prion protein, PrP. Although cases of clinical vCJD are rare, there is evidence there may be tens of thousands of infectious carriers in the United Kingdom alone. This raises concern about the potential for perpetuation of infection via medical procedures, in particular transfusion of contaminated blood products. Accurate biochemical detection of prion infection is crucial to mitigate risk and we have previously reported a blood assay for vCJD. This assay is sensitive for abnormal PrP conformers at the earliest stages of preclinical prion disease in mice and precedes the maximum infectious titre in blood. Not only does this support the possibility of screening asymptomatic individuals, it will also facilitate the elucidation of the complex relationship that exists between the ensemble of abnormal PrP conformers present in blood and the relationship to infectivity.
In-situ microfluidic controlled, low temperature hydrothermal growth of nanoflakes for dye-sensitized solar cells
Authors: Zhao Chao , Zhang Jia , Hu Yue , Robertson Neil , Hu Ping An , Child David , Gibson Desmond , Fu Yong Qing
Published: December 2015

In this paper, an in-situ microfluidic control unit (MCU) was designed and applied in a hydrothermal synthesis process, which provides an easy way to localize liquid-phase reaction and realize selective synthesis and direct growth of nanostructures as well as their morphology, all in a low-temperature and atmospheric environment. The morphology was controlled through controlling the amount of additivities using the MCU. This achieved a facile fabrication of Al doped ZnO (AZO) nanoflakes vertically grown on flexible polymer substrates with enhanced light scattering and dye loading capabilities. Flexible DSSCs with a significant enhancement (410% compare to ZnO NRs based devices) in power conversion efficiency were obtained using AZO nanoflake photoanodes of 6 μm thick, due to the enhancement in electron mobility and reduction in recombination. This hydrothermal synthesis using the in-situ MCU provides an efficient and scalable technique to synthesize controllable nanostructures with characteristics of easy set-up, low energy consumption and low cost.