bluuebunny/crossref_metadata_2025 huggingface dataset:
Time Domain NMR in Polymer Science: From the Laboratory to the Industry
Authors: Besghini Denise , Mauri Michele , Simonutti Roberto
Published: April 2019

Highly controlled polymers and nanostructures are increasingly translated from the lab to the industry. Together with the industrialization of complex systems from renewable sources, a paradigm change in the processing of plastics and rubbers is underway, requiring a new generation of analytical tools. Here, we present the recent developments in time domain NMR (TD-NMR), starting with an introduction of the methods. Several examples illustrate the new take on traditional issues like the measurement of crosslink density in vulcanized rubber or the monitoring of crystallization kinetics, as well as the unique information that can be extracted from multiphase, nanophase and composite materials. Generally, TD-NMR is capable of determining structural parameters that are in agreement with other techniques and with the final macroscopic properties of industrial interest, as well as reveal details on the local homogeneity that are difficult to obtain otherwise. Considering its moderate technical and space requirements of performing, TD-NMR is a good candidate for assisting product and process development in several applications throughout the rubber, plastics, composites and adhesives industry.
Physical Properties of Jatropha curcas L. Fruits and Seeds with Respect to Their Maturity Stage
Authors: Romuli Sebastian , Karaj Shkelqim , Müller Joachim
Published: April 2019

Jatropha curcas L. is a multipurpose bioenergy crop. Physical properties of J. curcas fruits and seeds are a fundamental knowledge required for the design of processing machinery. Therefore, this research investigates the physical properties at different maturity stages as indicated by pericarp color of the fruits (green, yellow, and black). Rupture force, hardness, deformation at rupture point, deformation ratio at rupture, and energy used for rupture were measured in the length and width direction of the fruits and in the length, width, and thickness of the seeds. During the course of maturing, a decrease in the unit mass and the surface area of the fruits was observed with a simultaneous increase for the seeds. Moisture content decreased during maturing. Bulk density and solid density were considerably different among maturity stages. The lowest porosity was observed in black fruits as well as “black” seeds. The highest dynamic and static angle of repose was detected for black fruits, while no substantial difference was observed between “yellow” and “black” seeds. The highest and lowest coefficient of static friction for all fruits and seeds was found on rubber and plastic surfaces.
A Comparative Study on the Effects of Passivation Methods on the Carrier Lifetime of RIE and MACE Silicon Micropillars
Authors: Kabalan Amal
Published: April 2019

Silicon micropillars have been suggested as one of the techniques for improving the efficiency of devices. Fabrication of micropillars has been done in several ways—Metal Assisted Chemical Etching (MACE) and Reactive Ion Etching (RIE) being the most popular techniques. These techniques include etching through the surface which results in surface damage that affects the carrier lifetime. This paper presents a study that compares the carrier lifetime of micropillars fabricated using RIE and MACE methods. It also looks at increasing carrier lifetime by surface treatment using three main approaches: surface passivation by depositing Al2O3, surface passivation by depositing SiO2/SiN, and surface passivation by etching using KOH and Hydrofluoric Nitric Acetic (HNA) solution. It was concluded that passivating with SiO2 and SiN results in the highest carrier lifetime on the MACE and RIE pillars.
Bioengineering an Artificial Human Blood–Brain Barrier in Rodents
Authors: Kamal Kimia , Waldau Ben
Published: April 2019

Our group has recently created a novel in-vivo human brain organoid vascularized with human iPSC-derived endothelial cells. In this review article, we discuss the challenges of creating a perfused human brain organoid model in an immunosuppressed rodent host and discuss potential applications for neurosurgical disease modeling.
Molecular Pathogenesis of Gene Regulation by the miR-150 Duplex: miR-150-3p Regulates TNS4 in Lung Adenocarcinoma
Authors: Misono Shunsuke , Seki Naohiko , Mizuno Keiko , Yamada Yasutaka , Uchida Akifumi , Sanada Hiroki , Moriya Shogo , Kikkawa Naoko , Kumamoto Tomohiro , Suetsugu Takayuki , Inoue Hiromasa
Published: April 2019

Based on our miRNA expression signatures, we focused on miR-150-5p (the guide strand) and miR-150-3p (the passenger strand) to investigate their functional significance in lung adenocarcinoma (LUAD). Downregulation of miR-150 duplex was confirmed in LUAD clinical specimens. In vitro assays revealed that ectopic expression of miR-150-5p and miR-150-3p inhibited cancer cell malignancy. We performed genome-wide gene expression analyses and in silico database searches to identify their oncogenic targets in LUAD cells. A total of 41 and 26 genes were identified as miR-150-5p and miR-150-3p targets, respectively, and they were closely involved in LUAD pathogenesis. Among the targets, we investigated the oncogenic roles of tensin 4 (TNS4) because high expression of TNS4 was strongly related to poorer prognosis of LUAD patients (disease-free survival: p = 0.0213 and overall survival: p = 0.0003). Expression of TNS4 was directly regulated by miR-150-3p in LUAD cells. Aberrant expression of TNS4 was detected in LUAD clinical specimens and its aberrant expression increased the aggressiveness of LUAD cells. Furthermore, we identified genes downstream from TNS4 that were associated with critical regulators of genomic stability. Our approach (discovery of anti-tumor miRNAs and their target RNAs for LUAD) will contribute to the elucidation of molecular networks involved in the malignant transformation of LUAD.
Hypoxia Selectively Impairs CAR-T Cells In Vitro
Authors: Berahovich Robert , Liu Xianghong , Zhou Hua , Tsadik Elias , Xu Shirley , Golubovskaya Vita , Wu Lijun
Published: April 2019

Hypoxia is a major characteristic of the solid tumor microenvironment. To understand how chimeric antigen receptor-T cells (CAR-T cells) function in hypoxic conditions, we characterized CD19-specific and BCMA-specific human CAR-T cells generated in atmospheric (18% oxygen) and hypoxic (1% oxygen) culture for expansion, differentiation status, and CD4:CD8 ratio. CAR-T cells expanded to a much lower extent in 1% oxygen than in 18% oxygen. Hypoxic CAR-T cells also had a less differentiated phenotype and a higher CD4:CD8 ratio than atmospheric CAR-T cells. CAR-T cells were then added to antigen-positive and antigen-negative tumor cell lines at the same or lower oxygen level and characterized for cytotoxicity, cytokine and granzyme B secretion, and PD-1 upregulation. Atmospheric and hypoxic CAR-T cells exhibited comparable cytolytic activity and PD-1 upregulation; however, cytokine production and granzyme B release were greatly decreased in 1% oxygen, even when the CAR-T cells were generated in atmospheric culture. Together, these data show that at solid tumor oxygen levels, CAR-T cells are impaired in expansion, differentiation and cytokine production. These effects may contribute to the inability of CAR-T cells to eradicate solid tumors seen in many patients.
Amino Acid Deprivation-Induced Autophagy Requires Upregulation of DIRAS3 through Reduction of E2F1 and E2F4 Transcriptional Repression
Authors: Sutton Margie N. , Huang Gilbert Y. , Zhou Jinhua , Mao Weiqun , Langley Robert , Lu Zhen , Bast Robert C.
Published: April 2019

Failure to cure ovarian cancer relates to the persistence of dormant, drug-resistant cancer cells following surgery and chemotherapy. “Second look” surgery can detect small, poorly vascularized nodules of persistent ovarian cancer in ~50% of patients, where >80% are undergoing autophagy and express DIRAS3. Autophagy is one mechanism by which dormant cancer cells survive in nutrient poor environments. DIRAS3 is a tumor suppressor gene downregulated in >60% of primary ovarian cancers by genetic, epigenetic, transcriptional and post-transcriptional mechanisms, that upon re-expression can induce autophagy and dormancy in a xenograft model of ovarian cancer. We examined the expression of DIRAS3 and autophagy in ovarian cancer cells following nutrient deprivation and the mechanism by which they are upregulated. We have found that DIRAS3 mediates autophagy induced by amino acid starvation, where nutrient sensing by mTOR plays a central role. Withdrawal of amino acids downregulates mTOR, decreases binding of E2F1/4 to the DIRAS3 promoter, upregulates DIRAS3 and induces autophagy. By contrast, acute amino acid deprivation did not affect epigenetic regulation of DIRAS3 or expression of miRNAs that regulate DIRAS3. Under nutrient poor conditions DIRAS3 can be transcriptionally upregulated, inducing autophagy that could sustain dormant ovarian cancer cells.
The Function of Non-Coding RNAs in Lung Cancer Tumorigenesis
Authors: Braicu Cornelia , Zimta Alina-Andreea , Harangus Antonia , Iurca Ioana , Irimie Alexandru , Coza Ovidiu , Berindan-Neagoe Ioana
Published: April 2019

Lung cancer is the most prevalent and deadliest cancer worldwide. A significant part of lung cancer studies is dedicated to the expression alterations of non-coding RNAs. The non-coding RNAs are transcripts that cannot be translated into proteins. While the study of microRNAs and siRNAs in lung cancer received a lot of attention over the last decade, highly efficient therapeutic option or the diagnostic methods based on non-coding RNAs are still lacking. Because of this, it is of utmost importance to direct future research on lung cancer towards analyzing other RNA types for which the currently available data indicates that are essential at modulating lung tumorigenesis. Through our review of studies on this subject, we identify the following non-coding RNAs as tumor suppressors: ts-46, ts-47, ts-101, ts-53, ts-3676, ts-4521 (tRNA fragments), SNORD116-26, HBII-420, SNORD15A, SNORA42 (snoRNAs), piRNA-like-163, piR-35127, the piR-46545 (piRNAs), CHIAP2, LOC100420907, RPL13AP17 (pseudogenes), and uc.454 (T-UCR). We also found non-coding RNAs with tumor-promoting function: tRF-Leu-CAG, tRNA-Leu, tRNA-Val (tRNA fragments), circ-RAD23B, circRNA 100146, circPVT1, circFGFR3, circ_0004015, circPUM1, circFLI1, circABCB10, circHIPK3 (circRNAs), SNORA42, SNORA3, SNORD46, SNORA21, SNORD28, SNORA47, SNORD66, SNORA68, SNORA78 (snoRNAs), piR-65, piR-34871, piR-52200, piR651 (piRNAs), hY4 5’ fragments (YRNAs), FAM83A-AS1, WRAP53, NKX2-1-AS1 (NATs), DUXAP8, SFTA1P (pseudogene transcripts), uc.338, uc.339 (T-UCRs), and hTERC.
Use of Co/Fe-Mixed Oxides as Heterogeneous Catalysts in Obtaining Biodiesel
Authors: Gutiérrez-Ortega Norma , Ramos-Ramírez Esthela , Serafín-Muñoz Alma , Zamorategui-Molina Adrián , Monjaraz-Vallejo Jesús
Published: April 2019

Catalyst-type mixed metal oxides with different compositions and Co/Fe ratios were obtained from layered double hydroxides to be used as heterogeneous catalysts in the production of biodiesel. The effect of the Co/Fe ratio on the precursors of the catalysts was analyzed, considering their thermal, textural and structural properties. The physicochemical properties of the catalysts were determined by thermogravimetric analysis (differential scanning calorimetry and thermogravimetric), X-ray diffraction, Fourier-transform infrared spectroscopy, Scanning Electron Microscopy-Energy Dispersive X-ray spectroscopy and N2-physisorption. The conversion to biodiesel using the different catalysts obtained was determined by diffuse reflectance infrared Fourier-transform spectroscopy and 1H-Nuclear magnetic resonance spectroscopy, allowing us to correlate the effect of the catalyst composition with the catalytic capacity. The conditions for obtaining biodiesel were optimized by selecting the catalyst and varying the percentage of catalyst, the methanol/oil ratio and the reaction time. The catalysts reached yields of conversion to biodiesel of up to 96% in 20 min of reaction using only 2% catalyst. The catalyst that showed the best catalytic activity contains a mixture of predominant crystalline and amorphous phases of CoFe2O4 and NaxCoO2. The results suggest that cobalt is a determinant in the activity of the catalyst when forming active sites in the crystalline network of mixed oxides for the transesterification of triglycerides, with high conversion capacity and selectivity to biodiesel.
Energy Efficient and Intermittently Variable Ammonia Synthesis over Mesoporous Carbon-Supported Cs-Ru Nanocatalysts
Authors: Nishi Masayasu , Chen Shih-Yuan , Takagi Hideyuki
Published: April 2019

The Cs-promoted Ru nanocatalysts supported on mesoporous carbon materials (denoted as Cs-Ru/MPC) and microporous activated carbon materials (denoted as Cs-Ru/AC) were prepared for the sustainable synthesis of ammonia under mild reaction conditions (<500 °C, 1 MPa). Both Ru and Cs species were homogeneously impregnated into the mesostructures of three commercial available mesoporous carbon materials annealed at 1500, 1800 and 2100 °C (termed MPC-15, MPC-18 and MPC-21, respectively), resulting in a series of Cs-Ru/MPC catalysts with Ru loadings of 2.5–10 wt % and a fixed Cs loading of 33 wt %, corresponding to Cs/Ru molar ratios of 2.5–10. However, the Ru and Cs species are larger than the pore mouths of microporous activated carbon (shortly termed AC) and, as a consequence, were mostly aggregated on the outer surface of the Cs-Ru/AC catalysts. The Cs-Ru/MPC catalysts are superior to the Cs-Ru/AC catalyst in catalysing mild ammonia synthesis, especially for the 2.5Cs-10Ru/MPC-18 catalyst with a Ru loading of 10 wt % and a Cs/Ru ratio of 2.5, which exhibited the highest activity across a wide SV range. It also showed an excellent response and stability during cycling tests over a severe temperature jump in a short time, presumably due to the open mesoporous carbon framework and suitable surface concentrations of CsOH and metallic Ru species at the catalytically active sites. This 2.5Cs-10Ru/MPC-18 catalyst with high activity, fast responsibility and good stability has potential application in intermittently variable ammonia synthesis using CO2-free hydrogen derived from electrolysis of water using renewable energy with fast variability.
Improvement of the Photoelectrochemical Performance of TiO2 Nanorod Array by PEDOT and Oxygen Vacancy Co-Modification
Authors: Yang Bin , Chen Guoqiang , Tian Huiwen , Wen Lei
Published: April 2019

In this study, oxygen vacancy modified TiO2 nanorod array photoelectrode was prepared by reducing hydrogen atmosphere to increase its free charge carrier density. Subsequently, a p-type conductive poly 3,4-ethylenedioxythiophene (PEDOT) layer was deposited on the surface of oxygen vacancy modified TiO2, to inhibit the surface states. Meanwhile, a p-n heterojunction formed between PEDOT and TiO2 to improve the separation of photo-induced carriers further. The photocurrent of TiO2 nanorod array increased to nearly 0.9 mA/cm2 after the co-modification under standard sunlight illumination, whose value is nearly nine times higher than that of pure TiO2 nanorod array. Thus, this is a promising modification method for TiO2 photoanode photoelectrochemical (PEC) performance improving.
NLRX1 Enhances Glutamate Uptake and Inhibits Glutamate Release by Astrocytes
Authors: Mahmoud Shaimaa , Gharagozloo Marjan , Simard Camille , Amrani Abdelaziz , Gris Denis
Published: April 2019

Uptake of glutamate from the extracellular space and glutamate release to neurons are two major processes conducted by astrocytes in the central nervous system (CNS) that protect against glutamate excitotoxicity and strengthen neuronal firing, respectively. During inflammatory conditions in the CNS, astrocytes may lose one or both of these functions, resulting in accumulation of the extracellular glutamate, which eventually leads to excitotoxic neuronal death, which in turn worsens the CNS inflammation. NLRX1 is an innate immune NOD-like receptor that inhibits the major inflammatory pathways. It is localized in the mitochondria and was shown to inhibit cell death, enhance ATP production, and dampen oxidative stress. In the current work, using primary murine astrocyte cultures from WT and Nlrx1-/- mice, we demonstrate that NLRX1 potentiates astrocytic glutamate uptake by enhancing mitochondrial functions and the functional activity of glutamate transporters. Also, we report that NLRX1 inhibits glutamate release from astrocytes by repressing Ca2+-mediated glutamate exocytosis. Our study, for the first time, identified NLRX1 as a potential regulator of glutamate homeostasis in the CNS.
Synergistic Effect of Ag and ZnO Nanoparticles on Polypyrrole-Incorporated Epoxy/2pack Coatings and Their Corrosion Performances in Chloride Solutions
Authors: Abdus Samad Ubair , Alam Mohammad Asif , Sherif El-Sayed M. , Alam Manawwar , Shaikh Hamid , Alharthi Nabeel H. , Al-Zahrani Saeed M.
Published: April 2019

In this study, two formulae (F1 and F2) of epoxy/2pack coatings incorporated with polypyrrole (PPy)-conducting polymer were produced from bisphenol-A type of epoxy resin (DGEBA) with the addition of Ag and ZnO nanoparticles. The synergism effect of Ag and ZnO nanoparticles on the mechanical and corrosion resistance properties was reported. The curing agent 2,4,6-tris (dimethylaminomethyl) phenol (ARADUR 3282-BD) was used under optimized stoichiometry values. The nanoparticles ratio in different wt.% were first dispersed in solvent by the sonication process and then added to epoxy/PPy composition. All the coated steel panels were cured at room temperature in a controlled dust free environment for 7 days in order to obtain a hard and intact coating. The dispersion of nano-size ZnO and Ag pigments was investigated using scanning electron microscopy (SEM) and its composition through an energy dispersive X-ray (EDX) technique. Conventional techniques and nano-indentation were also performed to observe the effect of ZnO and Ag synergism content on the hardness and modulus of elasticity at nano scale. The corrosion behavior of the coated samples was investigated at room temperature in 3.5% NaCl solution using electrochemical impedance spectroscopy (EIS). The synergism effect of nanoparticles along with PPy resulted in an enhancement of mechanical and corrosion-resistant properties.
On the Statistical Properties of Multiscale Permutation Entropy: Characterization of the Estimator’s Variance
Authors: Dávalos Antonio , Jabloun Meryem , Ravier Philippe , Buttelli Olivier
Published: April 2019

Permutation Entropy (PE) and Multiscale Permutation Entropy (MPE) have been extensively used in the analysis of time series searching for regularities. Although PE has been explored and characterized, there is still a lack of theoretical background regarding MPE. Therefore, we expand the available MPE theory by developing an explicit expression for the estimator’s variance as a function of time scale and ordinal pattern distribution. We derived the MPE Cramér–Rao Lower Bound (CRLB) to test the efficiency of our theoretical result. We also tested our formulation against MPE variance measurements from simulated surrogate signals. We found the MPE variance symmetric around the point of equally probable patterns, showing clear maxima and minima. This implies that the MPE variance is directly linked to the MPE measurement itself, and there is a region where the variance is maximum. This effect arises directly from the pattern distribution, and it is unrelated to the time scale or the signal length. The MPE variance also increases linearly with time scale, except when the MPE measurement is close to its maximum, where the variance presents quadratic growth. The expression approaches the CRLB asymptotically, with fast convergence. The theoretical variance is close to the results from simulations, and appears consistently below the actual measurements. By knowing the MPE variance, it is possible to have a clear precision criterion for statistical comparison in real-life applications.
Theoretical Analysis of a Novel Microstructure Fiber Sensor Based on Lossy Mode Resonance
Authors: Wang Xue-Zhou , Wang Qi
Published: April 2019

In this paper, we proposed a novel D-shaped microstructure fiber sensor based on lossy mode resonance (LMR). TiO2/HfO2 bilayer film is coated on the exposed-core portion of photonic crystal fiber (PCF) as a sensing channel. The asymmetrical LMR region generates strong birefringence, which leads to the separation of X polarization and Y polarization. This structure excites a stronger evanescent field than the conventional D-shaped fiber, thereby greatly improving the sensor sensitivity. Additionally, the metallic oxide bilayer can further enhance the sensor’s performance. We numerically investigated the influence of the number of air holes removed in PCF on the sensor performance and the proportion of TiO2 to HfO2 in theory for the first time. The results show that an ultra-high sensitivity of 140,000 nm/RIU is obtained, which is an order of magnitude higher than that of surface plasmon resonance sensors with a similar waveguide structure and LMR sensor coated film. This achievement means that LMR-based sensing systems are more sensitive than many sensors in real-time and distributed measurements, which will play an extremely important guiding role in the structural design of microstructure fiber sensors in the future.
Dynamic Crack Initiation Toughness of Shale under Impact Loading
Authors: Yang Guoliang , Li Xuguang , Bi Jingjiu , Cheng Shuaijie
Published: April 2019

The impact loading of a notched semi-circular bend (NSCB) specimen of outcrop shale in Changning Sichuan was carried out using a split Hopkinson pressure bar (SHPB) to study the effect of shale bedding on the dynamic crack initiation toughness. Three loading configurations were tested: Crack-divider, Crack-splitter and Crack-arrester loading. Bedding plane has a significant effect on the crack initiation of shale. Under the Crack-divider and Crack-splitter modes, shale had lower dynamic crack initiation toughness. The dynamic crack initiation toughness of the shale was affected by the loading rate for all three loading configurations. The correlation between loading rate and dynamic crack initiation toughness was most significant for the Crack-arrester mode, while the Crack-splitter mode was the weakest. When loading was carried out on Crack-arrester, the bedding plane could change the direction of crack growth. In the Crack-splitter mode, only a small impact energy was needed to achieve effective expansion of a crack. The research results provide a theoretical basis for shale cracking.
Mode Recognition and Fault Positioning of Permanent Magnet Demagnetization for PMSM
Authors: Gao Caixia , Nie Yanjie , Si Jikai , Fu Ziyi , Feng Haichao
Published: April 2019

This paper proposes a demagnetization fault detection, mode recognition, magnetic pole positioning, and degree evaluation method for permanent magnet synchronous motors. First, the analytical model of the single-coil no-load back electromotive force (EMF) of demagnetization fault for Permanent magnet synchronous motor (PMSM) arbitrary magnetic poles is established. In the analytical model, the single-coil no-load back EMF residual of the health state and the single magnetic pole sequential demagnetization fault are calculated and normalized. Model results are used as the fault sample database. Second, the energy interval database of the single-coil no-load back EMF residual with different numbers of magnetic pole demagnetization is established. Demagnetization fault detection and degree evaluation are performed by the real-time acquired amplitudes of the single-coil no-load back EMF residual. The number of demagnetization poles is determined by comparing the energy of the single-coil no-load back EMF residual with the energy interval database. Demagnetization mode recognition and magnetic pole positioning are realized by analyzing the correlation coefficients between normalized the single-coil no-load back EMF residual and the fault sample database. Finally, results of analysis of the finite element simulation validate the feasibility and effectiveness of the proposed method.
An Empirical Study on Low Emission Taxiing Path Optimization of Aircrafts on Airport Surfaces from the Perspective of Reducing Carbon Emissions
Authors: Li Nan , Sun Yu , Yu Jian , Li Jian-Cheng , Zhang Hong-fei , Tsai Sangbing
Published: April 2019

Aircraft emissions are the main cause of airport air pollution. One of the keys to achieving airport energy conservation and emission reduction is to optimize aircraft taxiing paths. The traditional optimization method based on the shortest taxi time is to model the aircraft under the assumption of uniform speed taxiing. Although it is easy to solve, it does not take into account the change of the velocity profile when the aircraft turns. In view of this, this paper comprehensively considered the aircraft’s taxiing distance, the number of large steering times and collision avoidance in the taxi, and established a path optimization model for aircraft taxiing at airport surface with the shortest total taxi time as the target. The genetic algorithm was used to solve the model. The experimental results show that the total fuel consumption and emissions of the aircraft are reduced by 35% and 46%, respectively, before optimization, and the taxi time is greatly reduced, which effectively avoids the taxiing conflict and reduces the pollutant emissions during the taxiing phase. Compared with traditional optimization methods that do not consider turning factors, energy saving and emission reduction effects are more significant. The proposed method is faster than other complex algorithms considering multiple factors, and has higher practical application value. It is expected to be applied in the more accurate airport surface real-time running trajectory optimization in the future. Future research will increase the actual interference factors of the airport, comprehensively analyze the actual situation of the airport’s inbound and outbound flights, dynamically adjust the taxiing path of the aircraft and maintain the real-time performance of the system, and further optimize the algorithm to improve the performance of the algorithm.
Diverse Responses of Vegetation Dynamics to Snow Cover Phenology over the Boreal Region
Authors: Xiong Tao , Zhang Hongyan , Zhao Jianjun , Zhang Zhengxiang , Guo Xiaoyi , Zhu Zhenhua , Shan Yu
Published: April 2019

Snow cover phenology plays an important role in vegetation dynamics over the boreal region, but the observed evidence of this interaction is limited. A comprehensive understanding of the changes in vegetation dynamics and snow cover phenology as well as the interactions between them is urgently needed. To investigate this, we calculated two indicators, the start of the growing season (SOS) and the annual maximum enhanced vegetation index (EVImax), as proxies of vegetation dynamics using the Moderate Resolution Imaging Spectroradiometer (MODIS) enhanced vegetation index (EVI). Snow cover duration (SCD) and snow cover end date (SCE) were also extracted from MODIS snow cover datasets. Then, we quantified the spatial-temporal changes in vegetation dynamics and snow cover phenology as well as the relationship between them over the boreal region. Our results showed that the EVImax generally demonstrated an increasing trend, but SOS varied in different regions and vegetation types from 2001 to 2014. The earlier onset of SOS was mainly concentrated in the Siberian boreal region. In the Eurasian boreal region, we observed an advance in the SCE and decrease in the SCD, while in the North American boreal region, the spatial distribution of the trends exhibited substantial heterogeneity. Our results also indicated that the snow cover phenology had significant impacts on the SOS and the EVImax, but the effects varied in different regions, vegetation types, and climate gradients. Our findings provide strong evidence of the interaction between vegetation dynamics and snow cover phenology, and snow cover should be considered when analyzing future vegetation dynamics in the boreal region.
Regulating Growth of Betula alnoides Buch. Ham. ex D. Don Seedlings with Combined Application of Paclobutrazol and Gibberellin
Authors: Wang Huan , Shen Wei , Guo Junjie , Wang Chunsheng , Zhao Zhigang
Published: April 2019

The rainy seasons have been becoming irregular and unpredictable under global warming now. This usually makes seedling preparation more difficult to match transplanting. Here applications of plant growth regulators, paclobutrazol (PBZ) and gibberellins (GA3) were studied with two trials to regulate growth of Betula alnoides Buch. Ham. ex D. Don container seedlings for the purpose of improving their quality when transplanting delayed. In the first trial five treatments (coded as P1 to P5) were laid out with total dosages of 0 mg (control), 2 mg, 6 mg, 10 mg and 20 mg PBZ per seedling to assess inhibitory effects of PBZ on growth of B. alnoides seedlings. After four and a half months, the second trial was carried out on the seedlings from the optimized PBZ treatments to detect growth recover of the seedlings by GA3, in which four treatments were arranged with GA3 dosages being 0, 1/10, 1/5 and 1/3 of the optimized paclobutrazol amounts applied. PBZ applications resulted in a significant decrease of height and root collar diameter growth since approximately one and two months after being treated, respectively. Among these treatments, P5 was the best one in controlling seedling growth, and its inhibitory effects lasted more than four and half months. PBZ treatments differed obviously in total seedling biomass from the control at 96 and 132 days after treatment (dat), and allocated more ratio of biomass into roots. Their root/shoot ratios increased and leaf areas decreased considerably with increasing PBZ dosage, while only P5-treated seedlings showed remarkable difference from the control in chlorophyll contents. The GA3 recovery showed that 15-day height increments of seedlings treated with GA3 were twice more than that without GA3 treatment, and did not differ significantly from the control without PBZ and GA3 treatment. It is concluded that the combined application of PBZ and GA3 can be recommended as a potential tool for regulating growth of B. alnoides seedlings, making it flexible to growing seedlings in the nursery.
Woody Litter Increases Headwater Stream Metal Export Ratio in an Alpine Forest
Authors: Liang Ziyi , Wu Fuzhong , Ni Xiangyin , Tan Bo , Zhang Li , Xu Zhenfeng , Hu Junyi , Yue Kai
Published: April 2019

Headwater streams have low productivity and are closely linked to forest ecosystems, which input a large amount of plant litter into streams. Most current studies have focused on the decomposition process of plant litter in streams, and the effects of non-woody and woody litter on metal transfer, accumulation, and storage in streams are poorly understood. Here, we addressed how non-woody and woody litter affect metals in headwater streams in an alpine forest on the Eastern Tibetan Plateau. This area is the source of many rivers and plays an important regulatory role in the regional climate and water conservation. Through comparisons of five metal concentrations, exports and storage in headwater streams with different input conditions of plant litter, our results showed that the input of woody litter could significantly increase flow discharge and increase the metal export ratio in the water. Similarly, the input of non-woody litter could reduce the metal concentration in the water and facilitate the stable storage of metals in the sediment in the headwater streams. Therefore, allochthonous non-woody and woody litter can affect the concentration of metals in water and sediment, and the transfer and accumulation of metals from upstream to downstream in headwater streams. This study provides basic data and new findings for understanding the effects of allochthonous plant litter on the accumulation and storage of metals in headwater forest streams and may provide new ideas for assessing and managing water quality in headwater streams in alpine forests.
Stand Structure and Composition Affect the Drought Sensitivity of Oregon White Oak (Quercus garryana Douglas ex Hook.) and Douglas-Fir (Pseudotsuga menziesii (Mirb.) Franco)
Authors: Gedalof Ze’ev , Franks Jennifer
Published: April 2019

Due to a suite of environmental changes, Oregon white oak (Quercus garryana Douglas ex Hook; called Gary oak in Canada) associated ecosystems at many North American sites are being encroached upon by Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii) and other conifer species. Alteration of stand structure and composition is causing substantial changes in the dynamics of these ecosystems, creating an environment in which Oregon white oak is not thriving. In this study we used dendrochronology to investigate the competitive dynamics between Oregon white oak and Douglas-fir in a mixed forest stand on Southern Vancouver Island. Significant species-specific differences in radial growth sensitivity to drought were found between Oregon white oak and Douglas-fir. Oregon white oak trees growing at high densities, or competing with Douglas-fir for moisture were found to be more sensitive to drought and more sensitive to growing conditions during the prior year. The response of Douglas-fir to drought was less variable, possibly due to the relatively low conifer densities at our study site, as well as the species’ ability to root graft, its higher shade tolerance than Oregon white oak, and its rapid growth rates that allow it to achieve a more dominant canopy position. The non-stationary response to climate exhibited by Oregon white oak provides insights into the mechanisms by which Oregon white oak savannas are being converted to coniferous woodland, but also suggest that tree-ring reconstructions of climate need to explicitly address changes in stand dynamics that could influence the growth–climate relationship
Transcriptomic and Metabolomic Analysis of the Heat-Stress Response of Populus tomentosa Carr.
Authors: Ren Shixiong , Ma Kaibiao , Lu Zhaogeng , Chen Gang , Cui Jiawen , Tong Peixi , Wang Li , Teng Nianjun , Jin Biao
Published: April 2019

Plants have evolved mechanisms of stress tolerance responses to heat stress. However, little is known about metabolic responses to heat stress in trees. In this study, we exposed Populus tomentosa Carr. to control (25 °C) and heat stress (45 °C) treatments and analyzed the metabolic and transcriptomic effects. Heat stress increased the cellular concentration of H2O2 and the activities of antioxidant enzymes. The levels of proline, raffinose, and melibiose were increased by heat stress, whereas those of pyruvate, fumarate, and myo-inositol were decreased. The expression levels of most genes (PSB27, PSB28, LHCA5, PETB, and PETC) related to the light-harvesting complexes and photosynthetic electron transport system were downregulated by heat stress. Association analysis between key genes and altered metabolites indicated that glycolysis was enhanced, whereas the tricarboxylic acid (TCA) cycle was suppressed. The inositol phosphate; galactose; valine, leucine, and isoleucine; and arginine and proline metabolic pathways were significantly affected by heat stress. In addition, several transcription factors, including HSFA2, HSFA3, HSFA9, HSF4, MYB27, MYB4R1, and bZIP60 were upregulated, whereas WRKY13 and WRKY50 were downregulated by heat stress. Interestingly, under heat stress, the expression of DREB1, DREB2, DREB2E, and DREB5 was dramatically upregulated at 12 h. Our results suggest that proline, raffinose, melibiose, and several genes (e.g., PSB27, LHCA5, and PETB) and transcription factors (e.g., HSFAs and DREBs) are involved in the response to heat stress in P. tomentosa.
Health-Related Quality of Life of Economically Disadvantaged African American Older Adults: Age and Gender Differences
Authors: Assari Shervin , Smith James , Bazargan Mohsen
Published: April 2019

Background: The association between age and health-related quality of life (HRQoL) is still under debate. While some research shows older age is associated with better HRQoL, other studies show no or negative association between age and HRQoL. In addition, while the association between age and HRQoL may depend on race, ethnicity, gender, and their intersections, most previous research on this link has been performed in predominantly White Middle Class. Objective: To explore gender differences in the association between age and mental and physical HRQoL in a sample of economically disadvantaged African American (AA) older adults. Methods: This cross-sectional survey was conducted in South Los Angeles between 2015 to 2018. A total number of 740 economically disadvantaged AA older adults (age ≥ 55 years) were enrolled in this study, using non-random sampling. This includes 266 AA men and 474 AA women. The independent variable of interest was age. Dependent variables of interest were physical component scores (PCS) and mental component scores (MCS), two main summary scores of the HRQoL, measured using Short Form-12 (SF-12). Gender was the moderator. Socioeconomic status (educational attainment and financial difficulty) were covariates. Linear regression models were used to analyze the data. Results: AA women reported worse PCS; however, gender did not impact MCS. In the pooled sample, high age was associated with better PCS and MCS. In the pooled sample, a significant interaction was found between gender and age on PCS, suggesting a stronger effect of age on PCS for AA men than AA women. In gender-stratified models, older age was associated with better PCS for AA men but not AA women. Older age was similarly and positively associated with better MCS for AA men and women. Conclusions: There may be some gender differences in the implications of ageing for the physical HRQoL of AA older adults. It is unclear how old age may have a boosting effect on physical HRQoL for AA men but not AA women. Future research should test gender differences in the effect of age on physical health indicators such as chronic disease as well as cognitive processes involved in the evaluation of own’s health in AA men and women.
Relationship between Physical Activity, Screen Time, and Sleep Quantity and Quality in US Adolescents Aged 16–19
Authors: Xu Furong , Adams Sue K. , Cohen Steven A. , Earp Jacob E. , Greaney Mary L.
Published: April 2019

Despite the health benefits associated with physical activity (PA), screen time reduction, and sleep quantity and quality, the relationships between PA, screen time, and sleep quantity and quality remain unclear in adolescents. The present study is a cross-sectional analysis of data from adolescents aged 16–19 years who participated in the 2005–2006 National Health and Nutrition Examination Survey (n = 542). Multivariable logistic regression models, adjusted for confounders, examined the relationship between objectively measured PA, self-reported screen time, and sleep quantity and quality. Respondents who met the current PA recommendation had 50% lower odds of having sufficient sleep (≥8 h) than those not meeting the recommendation (OR = 0.50, 95% CI: 0.26, 0.94). Respondents who met the screen time recommendation (≤2 h/day) had 55% lower odds of reporting poor sleep quality than those whose screen time exceeded the recommendation (OR = 0.45, 95% CI: 0.22, 0.91), with similar patterns observed for females and males. However, males who met both PA and screen time recommendations had 73% lower odds of reporting poor sleep quality than males who met neither recommendation (OR = 0.27, 95% CI: 0.07, 0.99). In conclusion, PA and screen time are associated with sleep quantity or sleep quality in adolescents, and there are differences in these associations by sex.
Metabolite Changes in Maternal and Fetal Plasma Following Spontaneous Labour at Term in Humans Using Untargeted Metabolomics Analysis: A Pilot Study
Authors: Birchenall Katherine A. , Welsh Gavin I. , López Bernal Andrés
Published: April 2019

The mechanism of human labour remains poorly understood, limiting our ability to manage complications of parturition such as preterm labour and induction of labour. In this study we have investigated the effect of labour on plasma metabolites immediately following delivery, comparing cord and maternal plasma taken from women who laboured spontaneously and delivered vaginally with women who were delivered via elective caesarean section and did not labour. Samples were analysed using ultra high-performance liquid chromatography-tandem mass spectrometry. Welch’s two-sample t-test was used to identify any significant differences. Of 826 metabolites measured, 26.9% (222/826) were significantly altered in maternal plasma and 21.1% (174/826) in cord plasma. Labour involves changes in many maternal organs and poses acute metabolic demands in the uterus and in the fetus and these are reflected in our results. While a proportion of these differences are likely to be secondary to the physiological demands of labour itself, these results present a comprehensive picture of the metabolome in the maternal and fetal circulations at the time of delivery and can be used to guide future studies. We discuss potential causal pathways for labour including endocannabinoids, ceramides, sphingolipids and steroids. Further work is necessary to confirm the specific pathways involved in the spontaneous onset of labour.
A Multiple Streams Approach to Understanding the Issues and Challenges of Lyme Disease Management in Canada’s Maritime Provinces
Authors: Levesque Mario , Klohn Matthew
Published: April 2019

This study examines potential challenges facing Lyme disease patients in Canada’s Maritime provinces—New Brunswick, Nova Scotia, Prince Edward Island—and considers how issues could be addressed. Reviews of both the academic and grey literature are complemented by surveys targeting both medical professionals and decision makers in government. Combined, the literature reviews and surveys demonstrate that there is considerable debate surrounding the effectiveness of testing, treatment options, and the existence of chronic Lyme disease. As the focus on the Maritimes demonstrates, these debates often pit the medical community against patients and patient advocates and, thus far, governments have been unable to produce policy that entirely pleases either side. Moving forward, this study recommends the creation of a discussion forum via a federal Commission of inquiry to review best practise guidelines for Lyme disease. The key is to foster an unbiased probe of central issues surrounding treatment and diagnosis without alienating stakeholders. This course of action will not necessarily solve the issue of Lyme disease, but would foster a greater understanding through dialogue that includes and validates the experiences of stakeholders, which is something that is currently missing.
Helicopter Emergency Medical Service (HEMS) Response in Rural Areas in Poland: Retrospective Study
Authors: Rzońca Patryk , Świeżewski Stanisław Paweł , Jalali Rakesh , Gotlib Joanna , Gałązkowski Robert
Published: April 2019

The aim of the study was to identify the characteristics of missions performed by HEMS (Helicopter Emergency Medical Service) crews and the analysis of health problems, which are the most common cause of intervention in rural areas in Poland. The study was conducted using a retrospective analysis based on the medical records of patients provided by the HEMS crew, who were present for the emergencies in rural areas in the period from January 2011 to December 2018. The final analysis included 37,085 cases of intervention by HEMS crews, which accounted for 54.91% of all the missions carried out in the study period. The majority (67.4%) of patients rescued were male, and just under a quarter of those rescued were aged between 50–64 years. Injuries (51.04%) and cardiovascular diseases (36.49%) were the main diagnoses found in the study group. Whereas injuries were significantly higher in the male group and patients below 64 years of age, cardiovascular diseases were higher in women and elderly patients (p < 0.001). Moreover, in the group of women myocardial infarction was significantly more frequent (30.95%) than men, while in the group of men head injuries (27.10%), multiple and multi-organ injuries (25.93%), sudden cardiac arrest (14.52%), stroke (12.19%), and epilepsy (4.95%) was significantly higher. Factors that are associated with the most common health problems of rural patients are: gender and age, as well as the seasons of the year and the values of the Glasgow Coma Scale (GCS), Revised Trauma Score (RTS), and National Advisory Committee for Aeronautics (NACA) used to assess the clinical status of patients.
A Two-stage Dynamic Undesirable Data Envelopment Analysis Model Focused on Media Reports and the Impact on Energy and Health Efficiency
Authors: Chen Huaming , Liu Jia , Li Ying , Chiu Yung-Ho , Lin Tai-Yu
Published: April 2019

Past research on energy and environmental issues in China has generally focused on energy and environmental efficiencies with no models having included the public health associations or the role of the media. Therefore, to fill this research gap, this paper used a modified Undesirable Dynamic Network model to analyze the efficiency of China’s energy, environment, health and media communications, from which it was found that the urban production efficiency stage was better than the health treatment stage, and that the energy efficiencies across the Chinese regions varied significantly, with only Beijing, Guangzhou, Lhasa and Nanning being found to have high efficiencies. Large urban gaps and low efficiencies were found for health expenditure, with the best performances being found in Fuzhou, Guangzhou, Haikou, Hefei, Nanning, and Urumqi. The regions with the best media communication efficiencies were Fuzhou, Guangzhou, Haikou, Hefei, Lhasa, Nanning and Urumqi, and the cities with the best respiratory disease efficiencies were Fuzhou, Guangzhou, Haikou, Lhasa, Nanning, Wuhan, Urumqi, Xian, and Yinchuan. Overall, significant efficiency improvements were needed in health expenditure and in particular in respiratory diseases as there were major differences across the country.
Acceptability of Intimate Partner Violence among Male Offenders: The Role of Set-Shifting and Emotion Decoding Dysfunctions as Cognitive Risk Factors
Authors: Romero-Martínez Ángel , Lila Marisol , Gracia Enrique , Rodriguez Christina , Moya-Albiol Luis
Published: April 2019

Attitudes towards the acceptability of intimate partner violence against women (IPVAW) contribute to an increased risk of IPVAW perpetration, and these attitudes are common among IPVAW offenders. Research suggests that IPVAW offenders present cognitive deficits related to information processing. Little is known, however, about how these deficits are related to the acceptability of IPVAW. The main aim of this study was to explore the relationship between specific cognitive deficits (i.e., deficits in attention switching, set-shifting, and emotion decoding abilities) and the acceptability of IPVAW in a sample of 84 IPVAW offenders. Results revealed that IPVAW offenders with deficits in attention switching, set-shifting, and emotion decoding abilities demonstrated greater acceptability of IPVAW, and these relationships remained significant after controlling for socio-demographic variables (i.e., age and educational level) and drug consumption. These results highlight the role of cognitive processes in maintaining attitudes of acceptability of IPVAW. Thus, the findings may guide professionals in developing specific intervention programs focused on improving cognitive abilities, in order to reduce the acceptability of IPVAW.