bluuebunny/crossref_metadata_2025 huggingface dataset:
Formation of Multilayer Graphene Domains with Strong Sulfur–Carbon Interaction and Enhanced Sulfur Reduction Zones for Lithium–Sulfur Battery Cathodes
Authors: Perez Beltran Saul , Balbuena Perla B.
Published: February 2018

A newly designed sulfur/graphene computational model emulates the electrochemical behavior of a Li–S battery cathode, promoting the S–C interaction through the edges of graphene sheets. A random mixture of eight‐membered sulfur rings mixed with small graphene sheets is simulated at 64 wt %sulfur loading. Structural stabilization and sulfur reduction calculations are performed with classical reactive molecular dynamics. This methodology allowed the collective behavior of the sulfur and graphene structures to be accounted for. The sulfur encapsulation induces ring opening and the sulfur phase evolves into a distribution of small chain‐like structures interacting with C through the graphene edges. This new arrangement of the sulfur phase not only leads to a less pronounced volume expansion during sulfur reduction but also to a different discharge voltage profile, in qualitative agreement with earlier reports on sulfur encapsulation in microporous carbon structures. The Li2S phase grows around ensembles of parallel graphene nanosheets during sulfur reduction. No diffusion of sulfur or lithium between graphene nanosheets is observed, and extended Li2S domains bridging the space between carbon ensembles are suppressed. The results emphasize the importance of morphology on the electrochemical performance of the composite material. The sulfur/graphene model outlined here provides new understanding of the graphene effects on the sulfur reduction behavior and the role that van der Waals interactions may play in promoting formation of multilayer graphene ensembles and small Li2S domains during sulfur reduction.
On the optimal flow allocation and information theoretically secure network coding design for multiple multicasts
Authors: Ding Weiwei , Wang Jin , Wang Xiumin , Lu Kejie , Zhao Ruimin , Zhu Yanqin
Published: February 2018

With linear network coding (LNC), the data packets transmitted in a communication network are coded packets, which are linear combinations of original data packets. Since the coded packets can be useful for multiple destinations in multicast, LNC has been shown as a promising technology to improve the network throughput. On the other hand, the original data packets can be encoded with random symbols and transmitted in the network to make sure that a passive attacker cannot obtain the information of these original data packets when the passive attacker cannot obtain enough coded packets. Therefore, LNC also provides secure transmission without using the traditional encryption and decryption. In this paper, we will study an Information Theoretically Secure Multiple Multicasts (ITSMM) problem with the following objectives: (1) maximizing the secure transmission rate (STR), (2) minimizing the random symbol rate (RSR), and (3) minimizing the bandwidth cost (BC), when the data transmission is information theoretically secure. We firstly theoretically analyze the ITSMM problem, which shows that it is equivalent to a problem of network flow with constraints on each intermediate node. We then formulate the ITSMM problem by 3 linear programmings to get the maximum STR, the minimum RSR, and the minimum BC. After that, we prove the sufficient condition for the size of finite field over which the information theoretically secure linear multicast code (ITSLMC) can be designed. At last, we give extensive simulations, which show that the proposed algorithms are effective and efficient.
Direct effects of warming increase woody plant abundance in a subarctic wetland
Authors: Carlson Lindsay G. , Beard Karen H. , Adler Peter B.
Published: February 2018

Both the direct effects of warming on a species’ vital rates and indirect effects of warming caused by interactions with neighboring species can influence plant populations. Furthermore, herbivory mediates the effects of warming on plant community composition in many systems. Thus, determining the importance of direct and indirect effects of warming, while considering the role of herbivory, can help predict long‐term plant community dynamics. We conducted a field experiment in the coastal wetlands of western Alaska to investigate how warming and herbivory influence the interactions and abundances of two common plant species, a sedge, Carex ramenskii, and a dwarf shrub, Salix ovalifolia. We used results from the experiment to model the equilibrium abundances of the species under different warming and grazing scenarios and to determine the contribution of direct and indirect effects to predict population changes. Consistent with the current composition of the landscape, model predictions suggest that Carex is more abundant than Salix under ambient temperatures with grazing (53% and 27% cover, respectively). However, with warming and grazing, Salix becomes more abundant than Carex (57% and 41% cover, respectively), reflecting both a negative response of Carex and a positive response of Salix to warming. While grazing reduced the cover of both species, herbivory did not prevent a shift in dominance from sedges to the dwarf shrub. Direct effects of climate change explained about 97% of the total predicted change in species cover, whereas indirect effects explained only 3% of the predicted change. Thus, indirect effects, mediated by interactions between Carex and Salix, were negligible, likely due to use of different niches and weak interspecific interactions. Results suggest that a 2°C increase could cause a shift in dominance from sedges to woody plants on the coast of western Alaska over decadal timescales, and this shift was largely a result of the direct effects of warming. Models predict this shift with or without goose herbivory. Our results are consistent with other studies showing an increase in woody plant abundance in the Arctic and suggest that shifts in plant–plant interactions are not driving this change.
Spatiotemporal patterns of unburned areas within fire perimeters in the northwestern United States from 1984 to 2014
Authors: Meddens Arjan J. H. , Kolden Crystal A. , Lutz James A. , Abatzoglou John T. , Hudak Andrew T.
Published: February 2018

A warming climate, fire exclusion, and land cover changes are altering the conditions that produced historical fire regimes and facilitating increased recent wildfire activity in the northwestern United States. Understanding the impacts of changing fire regimes on forest recruitment and succession, species distributions, carbon cycling, and ecosystem services is critical, but challenging across broad spatial scales. One important and understudied aspect of fire regimes is the unburned area within fire perimeters; these areas can function as fire refugia across the landscape during and after wildfire by providing habitat and seed sources. With increasing fire activity, there is speculation that fire intensity and combustion completeness are also increasing, which we hypothesized would yield smaller unburned proportions and changes in fire refugia patterns. We sought to determine (1) whether the unburned proportion of wildfires decreased across the northwestern United States from 1984 to 2014 and (2) whether patterns of unburned patches were significantly different across ecoregions, land cover type, and land ownership. We utilized a Landsat‐derived geospatial database of unburned islands within 2298 fires across the inland northwestern USA (including eastern Washington, eastern Oregon, and Idaho) from 1984 to 2014. We evaluated patterns of the total unburned proportion and spatial patterns of unburned patches of the fires across different ecoregions, land cover types, and land ownership. We found that unburned area proportion exhibited no change over the three decades, suggesting that recent trends in area burned and overall severity have not affected fire refugia, important to post‐fire ecosystem recovery. There were ecoregional differences in mean unburned proportion, patch area, and patch density, suggesting influences of vegetation and topography on the formation of unburned area. These foundation findings suggest that complex drivers control unburned island formation, and yield insights to locate potential important fire refugia across the inland northwest.
Synthesis, Substitution, and Oxidation of Imidazole‐2‐thione Based Tricyclic 1,4‐Dihydro‐1,4‐diphosphinines
Authors: Koner Abhishek , Sauerbrey Susanne , Schnakenburg Gregor , Bauzá Antonio , Frontera Antonio , Streubel Rainer
Published: February 2018

Herein, the synthesis and chemistry of P‐functional tricyclic 1,4‐dihydro‐1,4‐diphosphinines is described, following a recent communication on their use as precursors of 1,4‐diphosphinines. In particular, ring formation of imidazole‐2‐thione‐based tricyclic 1,4‐dihydro‐1,4‐diphosphinines 4a,b {–[P(Me2N)IMSR,R]2–; IMSR,R = 1,3‐dialkylimidazole‐2‐thione‐4‐yl}, first detected as side products, has been optimized to access 4d–f {–[P(Et2N)IMSR,R]2–; IMSR,R = 1,3‐dialkylimidazole‐2‐thione‐4‐yl}. The 1,4‐dihydro‐1,4‐dichloro‐1,4‐diphosphinines 8a,b {–[P(Cl)IMSR,R]2–; IMSR,R = 1,3‐dialkylimidazole‐2‐thione‐4‐yl}, easily obtained from 4, are ideal starting materials for P‐substituted products 9a–c (P–R; R = nBu, TMSC2–). The P‐diorganoamino derivatives 4d–f are used to synthesize bis(P–oxides) 10a–c and bis(P‐sulfides) 11a–c, and similarly, the bis(P–borane) adducts 13a–c. The first examples of bis(spirophosphorane) derivatives 12a–c, featuring two benzodioxaphosphole units, are synthesized by the reaction of 4d–f with o‐chloranil. Attempts to access bis(phosphonium) derivatives using methyl trifluoromethanesulfonate have resulted in S‐methylation of 4d–f, and hence, have furnished the first examples of tricyclic 1,4‐dihydro‐1,4‐diphosphinines possessing two imidazolium units 14a,b {[–{P(Me2N)‐IMSMeR,R}2–](CF3SO3)2; IMSMeR,R = 1,3‐dialkyl‐2‐thiomethyl‐imidazolium‐4‐yl}.
An Electrochemical Sensor Based on Silver Nanoparticles‐Benzalkonium Chloride for the Voltammetric Determination of Antiviral Drug Tenofovir
Authors: Ozcelikay Goksu , Dogan‐Topal Burcu , Ozkan Sibel A.
Published: February 2018

A simple voltammetric nanosensor was described for the highly sensitive determination of antiviral drug Tenofovir. The benzalkonium chloride and silver nanoparticles were associated to build a nanosensor on glassy carbon electrode. Surface characterictics were achieved using scanning electron microscopic technique. The voltammetric measurements were performed in pH range between 1.0 and 10.0 using cyclic, adsorptive stripping differential pulse and adsorptive stripping square wave voltammetry. The linear dependence of the peak current on the square root of scan rates and the slope value (0.770) demonstrated that the oxidation of tenofovir is a mix diffusion‐adsorption controlled process in pH 5.70 acetate buffer. The linearity range was found to be 6.0×10−8–1.0×10−6 M, and nanosensor displayed an excellent detection limit of 2.39×10−9 M by square wave adsorptive stripping voltammetry. The developed nanosensor was successfully applied for the determination of Tenofovir in pharmaceutical dosage form. Moreover, the voltammetric oxidation pathway of tenofovir was also investigated at bare glassy carbon electrode comparing with some possible model compounds (Adenine and Adefovir).
Normative data for the Montreal Cognitive Assessment (MoCA) and the Memory Index Score (MoCA‐MIS) in Brazil: Adjusting the nonlinear effects of education with fractional polynomials
Authors: Apolinario Daniel , dos Santos Marília Funchal , Sassaki Eduardo , Pegoraro Fernanda , Pedrini Anna Vitoria Alves , Cestari Bruna , Amaral Ana Helena , Mitt Mayra , Müller Marina Bellatti , Suemoto Claudia Kimie , Aprahamian Ivan
Published: February 2018

Objective

To provide age‐corrected and education‐corrected norms for the Montreal Cognitive Assessment (MoCA) and the Memory Index Score (MoCA‐MIS) in Brazil.

Methods

Community‐dwelling outpatients were enrolled if they had no history of neurologic or psychiatric diseases and were not taking any drugs with effects on the central nervous system. Dementia has been excluded with the Functional Activities Questionnaire. The final sample consisted of 597 cognitively healthy Brazilians aged 50 to 90 years. To account for nonlinear relationships, we have used fractional polynomials that provide a flexible parameterization for continuous variables.

Results

According to the original proposed cutoff (≤25 points), 87% of our sample would be considered impaired. Even using a more conservative suggestion (≤22 points), 67% of our normative sample would be regarded as impaired. These data reinforce the need of adjusting cutoffs for schooling in populations with heterogeneous educational backgrounds. MoCA scores presented a nonlinear positive association with education tending to a plateau at higher levels (P < 0.001). On the other hand, MoCA‐MIS scores presented a nonlinear negative relationship with age, with an accelerated pattern at higher age levels (P < 0.001).

Conclusions

We presented normative data for the MoCA and the MoCA‐MIS that will facilitate the use of the test in Brazil and, potentially, in other populations with substantial proportions of low‐educated individuals. Moreover, we described a systematic approach for adjusting the effects of age and education using fractional polynomials and provided suggestions on how to account for the nonlinear relationship that is frequently encountered between demographic factors and measures of cognitive performance.
Utilization of health‐care services by young children: The aftermath of the Turkish Health Transformation Program
Authors: Caner Asena , Karaoğlan Deniz , Yaşar Gülbiye
Published: February 2018

The Turkish Health Transformation Program, initiated in 2003, has identified achieving universal access to health care as 1 of its main tenets. To date, substantial progress has been made toward universal health coverage. Service utilization statistics display an upward trend. In this study, we use official and nationally representative microdata collected by the Turkish Health Research Surveys to examine young children's (ages 0‐5) utilization of health services. Children in this age group deserve special attention because adverse health conditions in early childhood are known to have long‐time consequences. Policy makers regularly monitor statistics such as infant mortality rate and under‐5 mortality rate. We conduct logistic regression analyses to explain the probabilities of being taken to a health institution, to a dentist, and being included in the newborn screening program. We use a rich set of explanatory variables that represent the socioeconomic status (SES) of the child's household. Contrary to our expectations and to the goals of universal health coverage is SES indicators such as the insurance ownership of the parent matter for utilization. Decomposition analyses confirm these findings and reveal that the increase in utilization should have been higher than observed. Children from low SES households should be given special attention and that research efforts should focus on identifying the barriers that still hinder children's utilization of health‐care services.
Placental implantation over prior cesarean scar causes activation of fetal regulatory T cells
Authors: Nguyen Tina A. , Kahn Daniel A. , Loewendorf Andrea I.
Published: February 2018

Introduction

Maternal‐fetal chimerism is miniscule, a testament to the integrity of the uteroplacental interface. The soundness of this border region is potentially altered through cesarean delivery of prior babies with uncertain consequences for the following pregnancies.

Methods

Using multicolor flow cytometry and quantitative PCR of non‐inherited maternal antigens we performed a retrospective case control pilot study and formulated the null hypothesis that placental implantation over a prior uterine scar does not result in the presence of memory Treg (CD45RO+) in the fetus. We then performed a power calculation and performed a blinded, appropriately powered prospective case control study to test the null hypothesis.

Results

Fetuses born to mothers with prior uterine scar have a roughly five times higher maternal to fetal microchimerism when the placenta directly interacts with the uterine scar. Unlike exposure to antigens in adult life, in utero antigenic exposure induces tolerogenic (Treg) responses in fetuses and we here report the presence of fetal Treg with a memory phenotype (CD45RO+). However, we only find such CD45RO+ fetal Tregs when the placenta abuts the uterine scar (Risk Ratio = 5 [p < 0.05 CI:(1.448 to 17.27)]). These memory fetal Tregs are functionally highly suppressive compared to CD45RA‐expressing fetal Tregs, and have specificity for non‐inherited maternal antigens.

Conclusions

We found that uterine scars, in the case of our study these scars are from prior c‐sections, fundamentally impair uterine integrity allowing for increased antigen exposure of the fetus; with our appropriately powered study we rejected the null hypothesis and accepted the alternative hypothesis that placental implantation over a prior uterine scar results in the presence of memory Treg (CD45RO+) in the fetus. Thus, our study demonstrates a previously unappreciated role for uterine integrity in limiting fetal antigenic exposure, a key element to avoid the formation of inappropriate tolerances by the fundamentally tolerogenic fetal immune system.
Coronary sinus thrombosis: Echocardiographic visualization in a patient with known risk factors
Authors: Milligan Gregory , Moscona John C.
Published: February 2018

Coronary sinus thrombosis is a rare and often overlooked diagnosis that can have fatal consequences. We report a case of acute coronary sinus thrombosis in a patient with systolic heart failure who had undergone recent right‐heart catheterization. The patient presented with recurrent presyncope, syncope, and shortness of breath. An echogenic focus consistent with a coronary sinus thrombus was visualized on transthoracic echocardiography that had not been seen previously on recent imaging. The patient was managed on oral anticoagulation. Awareness of patients at risk for coronary sinus thrombosis can lead to early detection via bedside echocardiography and early management.
Regression equations for calculation of z scores for echocardiographic measurements of left heart structures in healthy Han Chinese children
Authors: Wang Shan‐Shan , Hong Wen‐Jing , Zhang Yu‐Qi , Chen Shu‐Bao , Huang Guo‐Ying , Zhang Hong‐Yan , Chen Li‐Jun , Wu Lan‐Ping , Shen Rong , Liu Yi‐Qing , Zhu Jun‐Xue
Published: February 2018

Objective

Clinical decision making in children with heart disease relies on detailed measurements of cardiac structures using two‐dimensional and M‐mode echocardiography. However, no echocardiographic reference values are available for the Chinese children. We aimed to establish z‐score regression equations for left heart structures in a population‐based cohort of healthy Chinese Han children.

Method

Echocardiography was performed in 545 children with a normal heart. The dimensions of the aortic valve annulus (AVA), aortic sinuses of Valsalva (ASV), sinotubular junction (STJ), ascending aorta (AAO), left atrium (LA), mitral valve annulus (MVA), interventricular septal end‐diastolic thickness (IVSd), interventricular septal end‐systolic thickness (IVSs), left ventricular end‐diastolic diameter (LVIDd), left ventricular end‐systolic diameter (LVIDs), left ventricular posterior wall end‐diastolic thickness (LVPWd), left ventricular posterior wall end‐systolic thickness (LVPWs) were measured. Regression analyses were conducted to relate the measurements of left heart structures to body surface area (BSA). Left ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS) were calculated. Several models were used, and the adjusted R2 values were compared for each model.

Results

AVA, ASV, STJ, AAO, LA, MVA, IVSd, IVSs, LVIDd, LVIDs, LVPWd, and LVPWs had a cubic relationship with BSA. LVEF and LVFS fell within a narrow range.

Conclusions

Our results provide reference values for z scores and regression equations for left heart structures in Han Chinese children. These data may help make a quick and accurate judgment of the routine clinical measurement of left heart structures in children with heart disease.
Microscopic study on the concretion of ceramics in the “Nanhai I” shipwreck of China, Southern Song Dynasty (1,127–1,279 A.D.)
Authors: Hao Xi‐Luo , Zhu Tie‐Quan , Xu Jin‐Jin , Wang Yan‐Rong , Zhang Xuan‐Wei
Published: February 2018

“Nanhai I” shipwreck of China Southern Song Dynasty is the oldest and the most integrally preserved shipwreck in the world. The related conservation and archeological research have caught great attention of different experts all over the world. In this study, different types of concretion covered on the surface of the ceramics in “Nanhai I” shipwreck were analyzed by X‐ray diffractometer, micro‐Raman spectrometer, and scanning electron microscope equipped with energy dispersive spectroscopy. Based on the analyses, we found that the grey concretion was mainly composed of quartz, aragonite, and calcite while the reddish concretion was mainly composed of pyrite and quartz. Our study indicated that the formation process of the grey concretion probably included the crystallization and transformation of aragonite, while the corrosion of iron implements and crystallization of pyrite were highly involved in the formation of reddish concretion.
Isatin‐(thio)semicarbazide/oxime‐1H‐1,2,3‐triazole‐coumarin Hybrids: Design, Synthesis, and in vitro Anti‐mycobacterial Evaluation
Authors: Xu Yan , Dang Ran , Guan Jianguo , Xu Zhi , Zhao Shijia , Hu Yuanqiang
Published: February 2018

Isatin and coumarin derivatives with potential anti‐tubercular activity, while (thio)semicarbazide/oxime and 1H‐1,2,3‐triazole moieties exhibited favorable properties such as hydrogen bonding and/or metal chelation capability, so integration of the four pharmacophores into one molecule may provide more effective anti‐tubercular candidates. Based on the consideration earlier, 12 isatin‐(thio)semicarbazide/oxime‐1H‐1,2,3‐triazole‐coumarin hybrids 8a–l were designed, synthesized, and evaluated for their in vitro anti‐mycobacterial activities against M. tuberculosis (MTB) H37Rv and MDR‐TB. The results showed that all the hybrids (MIC: 50–>200 μg/mL) exhibited weak to moderate inhibitory activity against MTB H37Rv and MDR‐TB, which were far less potent than the references isoniazid (MIC: 0.05 μg/mL) and rifampicin (MIC: 0.39 μg/mL) against MTB H37Rv. The most active hybrid 8h (MIC: 50 μg/mL) was comparable with rifampicin (MIC: 32 μg/mL) and more active than isoniazid (MIC: >128 μg/mL) against MDR‐TB, could be act as a lead for further optimization. Moreover, the enriched structure–activity relationship paved the way to the further rational development of this kind of hybrids.
Coumarin–triazole Hybrids and Their Biological Activities
Authors: Fan Yi‐Lei , Ke Xing , Liu Min
Published: February 2018

Hybridization is emerged as a promising strategy in the discovery of new drugs, especially these with complimentary activities and multiple pharmacological targets that are the potential weapons to prevent the drug resistance. Currently, several hybrids are under different stages of clinical trial, and may be introduced into clinical practice to treat various diseases in the near future. Triazoles including 1,2,3‐triazole and 1,2,4‐triazole as well as coumarins occupy an important position in medicinal chemistry attribute to their various biological activities, and some of them have been used in clinical practice. Obviously, hybridization of these two pharmacophores may lead to novel candidates with broader spectrum, more effective, lower toxicity, and multiple mechanisms of action. This review aims to outline the biological activities of coumarin–triazole hybrids, and discuss their structure–activity relationship to pave the way for the further rational development of this kind of hybrids.
Novel Disubstituted Calix[4]arenes Containing Chromogenic Groups on the Lower Rim: Synthesis, Structural Identification, and Absorption Properties
Authors: Şener Nesrin , Erişkin Selinay , Gür Mahmut , Şener İzzet
Published: February 2018

5,11,17,23‐Tetra‐tert‐butyl‐25,26,27,28‐tetrahydroxycalix[4]arene and 25,26,27,28‐tetrahydroxycalix[4]arene were synthesized based on previous literature. Firstly, several azo dyes were synthesized, and then, these dyestuffs were chlorinated through reaction with thionyl chloride. Secondly, the azo compounds bonded with methylene chloride and reacted with 25,26,27,28‐tetrahydroxycalix[4]arene, and then, six novel disazocalix[4]arene derivatives 4(a–f) were achieved. Their structures were characterized as Fourier transform infrared, 1H‐NMR, and elemental analysis. In this study, we investigated the solvatochromic properties of the compounds and the acid–base effect on their ultraviolet–visible absorption by using six solvents.
Efficient Synthesis of New Benzofuran‐based Thiazoles and Investigation of their Cytotoxic Activity Against Human Breast Carcinoma Cell Lines
Authors: Gomha Sobhi M. , Abdelhamid Abdou O. , Abdelrehem Nadia A. , Kandeel Sahar M.
Published: February 2018

A new series of 1,3‐thiazole‐benzofuran derivatives was synthesized via heterocyclization of 2‐(1‐(6‐alkoxy‐4,7‐dimethoxybenzofuran‐5‐yl)ethylidene)‐2‐methyl‐2l4‐diazane‐1‐carbothioamides with hydrazonoyl halides. Also, 1‐(4,7‐dimethoxybenzofuran‐5‐yl)‐3‐phenylprop‐2‐en‐1‐one derivatives were used for synthesis of another series of 1,3‐thiazole‐pyrazole‐benzofuran. The structure of the newly synthesized products was elucidated via elemental analysis, spectral data, and alternative routes whenever possible. Seven new compounds were evaluated for their anticancer activity against the human breast carcinoma (MCF‐7) cell lines compared with doxorubicin drug. The results revealed that some new compounds showed promising anticancer activity.
Darunavir/cobicistat showing similar effectiveness as darunavir/ritonavir monotherapy despite lower trough concentrations
Authors: Gutierrez‐Valencia Alicia , Trujillo‐Rodriguez Maria , Fernandez‐Magdaleno Tamara , Espinosa Nuria , Viciana Pompeyo , López‐Cortés Luis F
Published: February 2018

Introduction

When darunavir (DRV) 800 mg is boosted with 150 mg cobicistat (DRVcobi), DRV trough concentration (Ctrough) is about 30% lower as compared to 100 mg ritonavir (DRVrtv). DRVcobi shows similar virological efficacy as DRVrtv when combined with two nucleos(t)ide analogue reverse‐transcriptase inhibitors, but it is unknown whether a lower DRV Ctrough would undermine the effectiveness of DRVcobi when given as monotherapy (mtDRVcobi).

Methods

Prospective observational study on virologically suppressed HIV‐infected subjects who switched to mtDRVcobi. Virological failure was defined as two consecutive HIV‐RNA >200 copies/mL. Efficacy was evaluated by intention‐to‐treat (ITT) and on‐treatment (OT) analyses, and compared with data from a previous cohort of subjects on mtDRVrtv conducted at our centre. Plasma DRV Ctrough was measured using LC–MS/MS.

Results

A total of 234 subjects were enrolled. At week 96, the efficacy rates were 67.8% (CI95, 61.8 to 73.7) by ITT and 86.9% (CI95, 78.0 to 87.7) by OT analyses. The corresponding rates in our historical DRVrtv controls were 67.6% (CI95, 60.0 to 75.2) and 83.6% (CI95: 77.2 to 90.0). A total of 135 DRV determinations were performed in 83 subjects throughout the follow‐up period, with a median plasma DRV Ctrough of 1305 ng/mL (range, 150 to 5895) compared with 1710 ng/mL (range, 200 to 3838) in subjects on monotherapy with DRVrtv (p = 0.05).

Conclusions

DRV Ctrough was lower in HIV‐infected subjects receiving DRVcobi than with DRVrtv. However, this did not appear to influence the efficacy of DRVcobi, when administered as monotherapy.
On taking the STING out of immune activation
Authors: Banete Andra , Seaver Kyle , Bakshi Devyani , Gee Katrina , Basta Sameh
Published: February 2018

Nearly a decade ago, an endoplasmic reticulum (ER) adaptor protein called stimulator of interferon genes (STING) was found to be critical in the induction of type I IFN production in response to DNA virus infection. STING functions by sensing cytoplasmic DNA and activates key transcription factors, including IFN regulatory factor (IRF)-3 and IRF7, to initiate type I IFN expression. Type I IFNs are vital in immunity against viral infections and can influence cancer cell proliferation, migration, and apoptosis. Several studies have shown that STING activation results in potent antitumor activity by generating strong tumor-specific cytotoxic T-cell responses. Moreover, compared with wild-type, STING-knockout mice show greater susceptibility to viral infections. In this review, we discuss the importance of STING signaling during the induction of immune responses, especially those associated with type I IFN in viral infections and tumor immunity. Furthermore, we highlight recent data that unravel how the STING signaling pathway can be negatively regulated.
The Madden–Julian oscillation during the 2016 summer and its possible impact on rainfall in China
Authors: Shao Xiaolu , Li Shuanglin , Liu Na , Song Jie
Published: February 2018

The summer rainfall in China in 2016 exhibited a substantial intraseasonal feature, with an intensification in June and July but a suppression in August over the Yangtze River Basin and North China. The Madden–Julian oscillation (MJO) during the summer and its impact on rainfall in China are investigated by conducting observational analyses and diagnostic linear baroclinic model (LBM) experiments. A significant MJO activity in the summer is observed with three MJO episodes corresponding to three stages of rainfall in China. The LBM is utilized to diagnose the circulation response to the tropical heating forcing associated with each MJO episode. The results suggest that much of the atmospheric circulation linked to the anomalous rainfall is attributed to the strong MJO episodes. During June–July (August), the enhanced (suppressed) convection over the tropical Indian Ocean along with the suppressed (enhanced) convection over the South China Sea (SCS) to the western Pacific excite an ‘East Asian–Pacific’ north‐eastward‐propagating Rossby wave train, inducing anomalous low‐level anticyclonic (cyclonic) flows over the northern SCS and the western North Pacific but cyclonic (anticyclonic) flows over North China. They lead to a westward (eastward) shift and strengthening (weakening) of the western Pacific subtropical high, thus favouring the intensification (suppression) in rainfall over the Yangtze River Basin and North China along with the opposite variation over South China. Relative to the first MJO episode, the MJO convection in the second episode causes a northward movement of the anomalous rainfall band from the Yangtze River Basin to North China. Apart from the impact on the above regions, the first (second and third) MJO episode favours an increase (reduction) in rainfall over Northeast China.
Evaluation of the subtropical westerly jet and its effects on the projected summer rainfall over central Asia using multi‐CMIP5 models
Authors: Zhao Yong , Yu Xiaojing , Yao Junqiang , Dong Xinning
Published: February 2018

Based on historical and RCP8.5 experiments, along with 25 Coupled Model Intercomparison Project Phase 5 (CMIP5) models, we evaluate the skills of the CMIP5 models in simulating the subtropical westerly jet (SWJ) and its effect on the projected summer rainfall over central Asia (CA). The historical experiments show that 23 models can well simulate the changes in the position and strength of the SWJ. Further analysis finds that 21 models can capture the relationship between the SWJ position change and summer rainfall over the domain of 55–85°E and 35–50°N and 17 models can capture the relationship between the SWJ strength change and summer rainfall over the domain of 55–75°E and 45–55°N, where 15 models can capture the relationships between both SWJ strength and position change with summer rainfall. Based on the SWJ change among the 15 models, except for the HadGEM2‐CC model, the 500 hPa winds of the rest 14 models well match the summer rainfall over CA. So the 14 models are used to do next analysis. In the last 50 years of the 21st century, only the inmcm4 model presents the change in the SWJ strength, and the rest 13 models present the changes in the SWJ position. Among above 13 models, 10 models maintain the relationships between the SWJ position change and summer rainfall over the domain of 55–85°E and 35–50°N into the future. Under the background of global warming, the changes in the SWJ position are well related to the sea surface temperatures (SSTs) over the Indian Ocean in the future. The SST warming over the Indian Ocean results in the South Asian summer monsoon weakening, corresponding to an anomalous anticyclone over the low‐level troposphere of the monsoon regions; this situation results in an anomalous cyclone at the upper level of the troposphere of the northwestern flank of the monsoon heating regions due to Matsuno–Gill‐type responses, which favour the SWJ axis shifting further south. In addition, we also compare the current projected summer rainfall over CA from our selected models with other selected previous models using different methods. The ensemble results show that more summer rainfall occurring in most of Kazakhstan and Xinjiang Province of northwestern China is more likely in the future; in the rest of the countries of CA, there are uncertainties regarding future rainfall changes.
Spatial variations and trends in AOD climatology over East Africa during 2002–2016: a comparative study using three satellite data sets
Authors: Boiyo Richard , Kumar K. Raghavendra , Zhao Tianliang
Published: February 2018

Aerosol optical depth (AOD) has become one of the most crucial parameters for climate change assessment. This study presents long‐term (2002–2016) spatio‐temporal distributions and trends in AOD over East Africa (EA) retrieved from the moderate‐resolution imaging spectroradiometer (MODIS) Aqua [Dark Target (DT) and Deep Blue (DB)] and multi‐angle imaging spectroradiometer (MISR). An inter‐comparison of AODs retrieved from different algorithms noticed significant positive correlations (r = 0.72 − 0.87) with MISR underestimating MODIS. Moderate (>0.5–0.8) to high (≥0.8) correlations in AOD exhibited over EA, with a few regions representing low (0–0.5) positive correlations. The spatial patterns of annual mean AOD were generally characterized by low (<0.2), moderate (0.2–0.35) and high (>0.35) centres over EA. The seasonal mean AODs over EA were found high (low) during the local dry (wet) seasons, with annual mean (±σ) values of 0.20 ± 0.01, 0.18 ± 0.01 and 0.20 ± 0.02 as observed by DT, DB and MISR, respectively. A single peak distribution of frequencies in AOD was observed by the three sensors in the interval 0.1–0.2, signifying a generally less polluted environment dominated by particular aerosol type. Linear trend analysis revealed an increase in AOD by 0.52, 0.57 and 0.74% year−1 as detected by MISR, DT and DB, respectively, and were consistent with those noted in key meteorological parameters. Furthermore, annual and seasonal spatial trends and tendencies revealed a general increase in AOD over EA, being positive and significant over the northern part of EA. Later, classification of major aerosol types over major cities in EA revealed dominance of continental (74.47%) followed by the mixed (16.22%) and biomass‐burning/urban‐industrial (8.02%) aerosols, with minor contributions from desert dust (1.03%) and clean maritime (0.32%) type of aerosols.
Characterization and comparison of rat monosodium iodoacetate and medial meniscal tear models of osteoarthritic pain
Authors: Brederson Jill‐Desiree , Chu Katharine L. , Xu Jun , Nikkel Arthur L. , Markosyan Stella , Jarvis Michael F. , Edelmayer Rebecca , Bitner Robert S. , McGaraughty Steve
Published: February 2018

Osteoarthritis (OA) is a degenerative form of arthritis that can result in loss of joint function and chronic pain. The pathological pain state that develops with OA disease involves plastic changes in the peripheral and central nervous systems, however, the cellular mechanisms underlying OA are not fully understood. We characterized the medial meniscal tear (MMT) surgical model and the intra‐articular injection of monosodium iodoacetate (MIA) chemical model of OA in rats. Both models produced histological changes in the knee joint and associated bones consistent with OA pathology. Both models also increased p38 activation in the L3, but not L4 dorsal root ganglia (DRG), increased tyrosine hydroxylase immunostaining in the L3 DRG indicating sympathetic sprouting, and increased phosphorylated (p)CREB in thalamic neurons. In MIA‐OA, but not MMT‐OA rats, p38 and pERK were increased in the spinal cord, and pCREB was enhanced in the prefrontal cortex. Using in vivo electrophysiology, elevated spontaneous activity and increased responsiveness of wide dynamic range neurons to stimulation of the knee was found in both models. However, a more widespread sensitization was observed in the MIA‐OA rats as neurons with paw receptive fields spontaneously fired at a greater rate in MIA‐OA than MMT‐OA rats. Taken together, the MIA and MMT models of OA share several common features associated with histopathology and sensitization of primary somatosensory pathways, but, observed differences between the models highlights unique consequences of the related specific injuries, and these differences should be considered when choosing an OA model and when interpreting data outcomes. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:2109–2117, 2018.
The C‐terminus of the amelogenin peptide influences the proliferation of human bone marrow mesenchymal stem cells
Authors: Kunimatsu Ryo , Awada Tetsuya , Yoshimi Yuki , Ando Kazuyo , Hirose Naoto , Tanne Yuki , Sumi Keisuke , Tanimoto Kotaro
Published: February 2018

Background

Amelogenins are a family of enamel matrix proteins that are important for formation of enamel. Amelogenins may induce division of mesenchymal stem cells (MSCs), among others. Recently, the C‐terminus of the amelogenin peptide (AMG‐CP) has been shown to enhance the proliferation of cementoblast lineage cells. The role of the amelogenin peptide on the proliferation of human MSCs and related alterations in the intracellular signaling pathway were studied.

Methods

MSCs were exposed to AMG‐CP in vitro. The MTS and 5‐bromo‐2′‐deoxyuridine (BrdU) assays were used to determine proliferation. Expression of the amelogenin receptor, lysosomal‐associated membrane protein 1 (LAMP1), was examined in MSCs with western blotting. Binding of AMG‐CP to LAMP1 was inhibited with anti‐LAMP1 antibody. Components of the mitogen‐activated protein kinase (MAPK)–extracellular signal‐regulated kinase (ERK) pathway were studied with western blotting and enzyme‐linked immunosorbent assay, and U0126, an MAPK inhibitor, was used to inhibit ERK activity.

Results

MSC proliferation was significantly increased in the presence of AMG‐CP and significantly inhibited by anti‐LAMP1 antibody or U0126. Increased phosphorylated ERK1/2 was observed in the presence of AMG‐CP, and decreased phosphorylated ERK1/2 was seen in the presence of anti‐LAMP1 antibody or U0126.

Conclusion

A C‐terminal amelogenin variant increased the proliferation of MSCs via an interaction with LAMP1 and the MAPK–ERK signaling pathway, indicating the possibility of using MSCs for tissue regeneration in the craniofacial region.
Titanium‐prepared platelet‐rich fibrin provides advantages on periodontal healing: A randomized split‐mouth clinical study
Authors: Arabaci Taner , Albayrak Mevlut
Published: February 2018

Background

The aim of this study to evaluate the contributions of titanium‐prepared platelet‐rich fibrin (T‐PRF) combined with open flap debridement (OFD) on biological markers in gingival crevicular fluid (GCF)and periodontal outcomes.

Methods

Twenty‐nine participants with chronic periodontitis were treated either with autologous T‐PRF+OFD or OFD alone. GCF growth factor levels and relative receptor activator nuclear factor kappa‐B/osteoprotegerin (RANKL/OPG) ratio at baseline and 2, 4, and 6 weeks postoperatively were analyzed, and clinical parameters such as probing depth (PD), relative attachment level (RAL) and gingival margin level (GML) at baseline and 9 months after surgery were compared.

Results

The mean PD reduction, RAL gain, and GML change were significantly greater in the OFD+T‐PRF sites than in the OFD sites (P = 0.033, P = 0.029, and P = 0.026, respectively). Both groups demonstrated increased growth factor levels at week 2 compared with baseline, followed by reductions at weeks 4 and 6. GCF growth factor levels in the test group were seen at higher concentrations with respect to control group until 6 weeks post‐surgery. During this 6‐week period, relative RANKL/OPG ratio was found significantly lower in the OFD+T‐PRF group compared to the OFD group(P < 0.05).

Conclusions

Using T‐PRF membrane combined with OFD provided significantly higher concentrations of growth factors and lower RANKL/OPG ratio in GCF for approximately 4 to 6 weeks, and improved periodontal healing compared to conventional flap sites.
High‐power, red‐light‐emitting diode irradiation enhances proliferation, osteogenic differentiation, and mineralization of human periodontal ligament stem cells via ERK signaling pathway
Authors: Yamauchi Nobuhiro , Taguchi Yoichiro , Kato Hirohito , Umeda Makoto
Published: February 2018

Background

Light‐emitting diode (LED) is attracting attention as a new light source for phototherapy. However, its effects on periodontal tissue regeneration remain unknown. The aim of this study was to examine the effects of high‐power, red LED irradiation on human periodontal ligament stem cells (PDLSCs), which play an important role in periodontal tissue regeneration.

Methods

PDLSCs were derived from adult human third molars. The light source was red LED (peak wavelength: 650 nm). Energy densities ranging from 0 to 10 J/cm2 were tested to determine the optimal dose. PDLSC proliferation was measured using two parameters: live cell protease and ATP levels. After the cells were induced to differentiate, the effect of LED irradiation on osteogenic differentiation and mineralization was examined, with particular focus on the extracellular signal‐regulated kinase (ERK)1/2 signaling pathway using an ERK inhibitor (PD98059).

Results

LED irradiation at 8 J/cm2 led to a significant increase in PDLSC proliferation and enhanced Runx2 and Osterix mRNA expression, Alkaline phosphatase activity, procollagen type I C‐peptide and osteocalcin production, calcium deposition, and alizarin red S staining. In addition, LED induced the activation of ERK1/2, and the effects of LED on PDLSC proliferation, differentiation, and mineralization could be suppressed by treatment with PD98059.

Conclusions

The results of this study show that 650‐nm high‐power, red, LED irradiation increases PDLSCs proliferation, and osteogenic differentiation and mineralization, mediated by ERK1/2 activation. These findings suggest that LED may be a useful tool for periodontal tissue regeneration.
An ultrasensitive chemiluminescence immunoassay for fumonisin B1 detection in cereals based on gold‐coated magnetic nanoparticles
Authors: Jie Mingsha , Yu Songcheng , Yu Fei , Liu Lie , He Leiliang , Li Yanqiang , Zhang Hongquan , Qu Lingbo , Harrington Peter de B , Wu Yongjun
Published: February 2018

BACKGROUND

In the present study, a novel highly sensitive magnetic enzyme chemiluminescence immunoassay (MECLIA) was developed to detect fumonisin B1 (FB1) in cereal samples. The gold‐coated magnetic nanoparticles (Fe3O4@Au, GoldMag) were used as solid phase carrier to develop a competitive CLIA for detecting FB1, in which FB1 in samples would compete with FB1‐ovalbumin coated on the surface of Fe3O4@Au nanoparticles for binding with FB1 antibodies. Successively, horseradish peroxidase labeled goat anti‐rabbit IgG (HRP‐IgG) was conjugated with FB1 antibodies on the microplate. In substrate solution containing luminol and H2O2, HRP‐IgG catalyzed luminol oxidation by H2O2, generating a high chemiluminescence signal. The FB1 immune GoldMag particles were characterized by Fourier transform infrared spectroscopy, scanning electron microscope and zeta potential analysis, etc.

RESULTS

The concentrations and the reaction times of these immunoreagents were optimized to improve the performances of this method. The established method could detect as low as 0.027 ng mL–1 FB1 from 0.05 ng mL–1 to 25 ng mL–1, demonstrating little cross‐reaction (less than 2.4%) with other structurally related compounds. The average intrassay relative SD (RSD) (n = 6) was 3.4% and the average interassay RSD (n = 6) was 5.4%. This method was successfully applied for the determination of FB1 in corn and wheat and gave recoveries of between 98–110% and 91–105%, respectively.

CONCLUSION

The results of the present study suggest that the MECLIA approach has potential application for high‐throughput fumonisin screening in cereals. © 2018 Society of Chemical Industry
Screening and analysis of potentially active components in Shenxiong glucose injection using UHPLC coupled with photodiode array detection and MS/MS
Authors: Zhou Meng , Li Rui , Liao Xiang‐Ming , Wang Zheng , Xu Guo‐Bo , Gong Zi‐Peng , Lu Yuan , He Xun , Li Yong‐Jun , Wang Yong‐Lin , Zheng Lin , Liao Shang‐Gao
Published: February 2018

Shenxiong glucose injection, a pharmaceutical preparation containing a water extract of the roots of Salvia miltiorrhizae and ligustrazine hydrochloride, is widely used in clinical to treat cardiovascular diseases in China. The chemical components of the water extract have been reported and the cardioprotective effects of the injection have been evaluated. However, the chemical constituents of the injection and their correlations with its pharmacological effects have not been established. In this study, 13 chemical constituents of the injection have been identified or characterized by ultra‐high performance liquid chromatography with diode array detection and electrospray ionization quadrupole time‐of‐flight tandem mass spectrometry. Besides, the potentially active compounds of this preparation that directly act on cardiac cells have been screened by cell extraction and ultra high performance liquid chromatography targeted multiple reaction monitoring. As a result, eight potentially active compounds, danshensu (1), ligustrazine hydrochloride (4), salvianolic acid I/H (7), lithospermic acid (8), salvianolic acid D (9), rosmarinic acid (10), salvianolic acid B (12), and salvianolic acid C (13), were obtained and structurally characterized from the 11 target compounds used for screening. The liquid chromatography with quadrupole time‐of‐flight mass spectrometry and liquid chromatography with multiple reaction monitoring tandem mass spectrometry combination method has demonstrated its potency for the screening, detection, and structural identification of bioactive compounds in a complex matrix.
Ultrasound Elastographic Measurement of Sciatic Nerve Displacement and Shear Strain During Active and Passive Knee Extension
Authors: Ellis Richard , Rohan Maheswaran , Fox James , Hitt Juvena , Langevin Helene , Henry Sharon
Published: February 2018

There is current need for objective measures of sciatic nerve mobility in patients with sciatic‐type pain. The objective of the study was to assess the feasibility and reliability of ultrasound elastography to quantify sciatic nerve displacement and shear strain at the sciatic nerve–hamstring muscle interface during active and passive knee extension‐flexion exercises performed while sitting in healthy people. Ultrasound elastography showed excellent intrarater within‐session reliability for assessing sciatic nerve displacement and sciatic nerve–hamstring muscle interface shear strain during active knee extension‐flexion exercises. These findings will inform similar future work conducted in patients with sciatic‐type pain.