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The global evapotranspiration (ET) shows an increasing trend with global warming in recent decades, while ET variation in different regions is still uncertain. Boreal forest ecosystem, as one of the most sensitive regions to climate change, are still poorly understood due to the sparse observation and the changing of ET in the boreal forest has been covered up for lower values compared to lower‐latitude regions. Based on the PT‐JPL model, we estimated the ET in the boreal forest during 1982–2015. The annual ET showed an increasing trend (0.5073 mm year−1). Seventy percentage of the boreal forest area is increasing which mainly occurred in Central Canada, Alaska, Central Siberia and Northern Europe, while 24% is decreasing, which occurred in the southern Siberia, Northern Mongolia and Northern Canada. The quantification of basic climatic factors shows that atmospheric demand is the main factor with an increasing trend which is accordance with the (a) increasing temperature; (b) annual precipitation is increasing providing increasing water supply for boreal forest. Factorial experiments were also conducted and showed that the climatic constraints that contribute mainly to ET have gradually shifted from net radiation to moisture restriction in the boreal forest. The moisture control tendency indicated that ET in the boreal forest was gradually controlled by humidity rather than energy, suggesting a limited water supply and an intensifying water cycle in the boreal forest. Plain Language Summary: Evapotranspiration (ET) is the process which water returns to the atmosphere from the surface through evaporation and plant transpiration. The ET process absorbs energy and requires continuous water and energy supply and is affected by climate change and in turn generates feedback to the climate. The study of ET changes is of great significance to understand the future climate change and the dryness tendency. The global ET is found to be increasing in recent decades, but the variation in spatial is still poor understood. Thus, this study examines the ET trend in boreal forests, one of the most sensitive regions to climate change. The results shows that the ET in boreal forest is increasing during 1982–2015, which is caused by the increasing atmospheric demand and precipitation according to the basic climatic control quantification. Experiments on environmental control factors show that the moisture has become the controlling factor that control ET. This may be related to the increased demand for atmospheric water caused by climate warming. Although regional precipitation also shows an increasing trend, this trend is lower than the increase of ET, indicating that climate change may cause water constraint on ET in the future, which will lead to regional drought. Key Points: The annual evapotranspiration (ET) showed an increasing trend in the boreal forestThe climatic constraints that contribute mainly to ET have gradually shifted from net radiation to moisture restriction in the boreal forest [ABSTRACT FROM AUTHOR]

The P300/CBP‐associating factor (PCAF), a histone acetyltransferase, is involved in metabolic and pathogenic diseases, particularly of the liver. The effects of PCAF on fine‐tuning liver diseases are extremely complex and vary according to different pathological conditions. This enzyme has dichotomous functions, depending on differently modified sites, which regulate the activities of various enzymes, metabolic functions, and gene expression. Here, we summarize the most recent findings on the functions and targets of PCAF in various metabolic and immunological processes in the liver and review these new discoveries and models of PCAF biology in three areas: hepatic metabolic syndrome, inflammatory disease, and cancer. Finally, we discuss the potential implications of these findings for therapeutic interventions in liver diseases. [ABSTRACT FROM AUTHOR]

Nanoscale components at neural interface are crucial factors for neural devices due to the complex nanoscale structure of neural tissue. Nitrogen‐doped graphene (g‐C3N4) was prepared and applied as a candidate material for the surface modification of neural electrodes. To better explore the practical applications of g‐C3N4, a conducting polymer of poly(3,4‐ethylenedioxythiophene) (PEDOT) was employed and a nanoporous composite of g‐C3N4/PEDOT was achieved with excellent electrochemical performance including low interfacial impedance, high electric capacity, and long‐term stability. Investigation revealed that the enhanced performance of the composite was attributed to its unique nanostructure, which was confirmed by field emission scanning electron microscopy, as well as the synergistic effect of the two components. Moreover, in vitro experiments demonstrated that g‐C3N4/PEDOT promoted robust cell growth, possessing excellent biocompatibility. Our study validates that the g‐C3N4/PEDOT nanocomposite is a promising candidate material to construct the interface between neural tissue and neural electrodes. POLYM. ENG. SCI., 58:1548–1554, 2018. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

The organic-inorganic hybrid nanocomposites from high-impact polystyrene/octavinyl polyhedral oligomeric silsesquioxane (HIPS/POSS) containing various percentages of POSS were prepared by free radical polymerization and characterized by Fourier transform infrared spectroscopy (FTIR), ³H-NMR, thermal gravity analysis (TGA), X-ray diffraction (XRD), and transmission electron microscopy (TEM). The octavinyl POSS has formed covalent bond connected PS-POSS hybrid with polystyrene. POSS can well disperse in the composites at the composition of 0.5 and 1 wt%. The mechanical properties and thermostability of HIPS/ POSS nanocomposites were significantly improved. The tensile strength, the izod impact strength, and the elongation at break of the nanocomposite containing 1 wt% of POSS was increased, respectively, by 15.73%, 75.62%, and 72.71% in comparison with pristine HIPS. The thermal decomposition temperature of HIPS/POSS (1 wt% of POSS) was 33°C higher than that of pristine HIPS. The HIPS/POSS nanocomposites showed great potential for applications in many fields, such as electric appliance and automotive trim. [ABSTRACT FROM AUTHOR]

The isotopic ratio of uranium-bearing particles could be used to detect undeclared nuclear activities. How to strengthen the analyzing ability of secondary ion mass spectrometry (SIMS) was important to get certain information. For this purpose, the oxygen flooding technique was studied to enhance the ability of measuring isotopic ratio in uranium particles. The influence of oxygen flooding on the sensitivity of U+, UO+ and UO2+ was checked by using uranium metal and uranium particle (CRM U200) samples. The major and minor isotopic ratios of uranium bearing particles were measured by U+, UO+ and UO2+. The result shows that the use of oxygen flooding technique has no effect on the sensitivity of U+ and the isotopic ratio 234U/238U and 235U/238U. However, the intensity of UO+ and UO2+ increased several times with the oxygen flooding. Besides, the accuracy and precision of major isotopic ratio measured by uranium-oxygen ions were better than that measured by U+. For the minor isotopic ratio (234U/238U), it cannot be measured by uranium-oxygen ions because of the interference of polyatomic ions on carbon mat. After changing sample mat, for example, silicon mat, it can be measured by UO+ and get better results with oxygen flooding technique. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A new flame retardant polycarbonate/magnesium oxide (PC/MgO) nanocomposite, with high flame retardancy was developed by melt compounding. The effect of MgO to the flame retardancy, thermal property, and thermal degradation kinetics were investigated. Limited oxygen index (LOI) test revealed that a little amount of MgO (2 wt %) led to significant enhancement (LOI = 36.8) in flame retardancy. Thermogravimetric analysis results demonstrated that the onset temperature of degradation and temperature of maximum degradation rate decreased in both air and N2 atmosphere. Apparent activation energy was estimated via Flynn-Wall-Ozawa method. Three steps in the thermal degradation kinetics were observed after incorporation of MgO into the matrix and the additive raised activation energies of the composite in the full range except the initial stage. It was interpreted that the flame retardancy of PC was influenced by MgO through the following two aspects: on the one hand, MgO catalyzed the thermal-oxidative degradation and accelerated a thermal protection/mass loss barrier at burning surface; on the other hand, the filler decreased activation energies in the initial step and improved thermal stability in the final period. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]

Previously, nano-sized calcium fluoride (CaF2) particles were prepared using a spray drying method by simultaneously feeding Ca(OH)2 and NH4F solutions to a two-liquid nozzle. The aim of the present study was to prepare better-dispersed nano-CaF2 particles by co-forming a soluble salt, sodium chloride (NaCl). NaCl of various concentrations were added to the NH4F solution, leading to formation of (CaF2+NaCl) composites with CaF2/NaCl molar ratios of 4/1, 4/4, and 4/16. Pure nano-CaF2 was also prepared as the control. Powder X-ray diffraction analysis showed that the products contained crystalline CaF2 and NaCl. Scanning electron microscopy examinations showed that both the CaF2/NaCl composite and pure CaF2 particles were about (50-800) nm in size and consisted of primary CaF2 particles of < 50 nm in size. BET surface area measurements showed similar primary particle sizes for all samples. Dynamic light scattering measurements showed that the washed (CaF2+NaCl) particles were much smaller than the pure CaF2 as the dissolution of NaCl 'freed' most of the primary CaF2 particles, leading to a greater degree of particle dispersion. The well-dispersed nano-CaF2 may be expected to be a more effective anticaries agent than NaF by providing longer lasting elevations of fluoride concentrations in oral fluids. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2011. [ABSTRACT FROM AUTHOR]

Top: Illustration of how to obtain 3D embryo images from a locust egg using OCT B‐scans. The internal structures of the embryo can be clearly identified as it develops. Bottom: The real time observation of katatrepsis and twist of a lowland locust embryo on days 7‐8, as the embryo develops. The embryonic movements can be readily identified by tracking the positions of the embryo's eyes (E1 and E2). Further details can be found in the article by Ya Su, Liya Wei, Hao Tan, et al. (e201960047). [ABSTRACT FROM AUTHOR]

Noninvasive visualization of embryos at different development stages is crucial for the understanding of the basic developmental biology. It is therefore desirable to have an imaging tool capable of rapidly evaluating the effects of gene manipulation or genome editing in developing embryos for the studies of gene functions and genetic engineering. Here, we propose and demonstrate a novel use of optical coherence tomography (OCT) to noninvasively exam the embryonic development of the migratory locusts in real time with 3‐dimensional (3D) view capability. In particular, we obtain the sufficiently high spatial resolution tomographic 2D and 3D images of live locust embryos throughout their development processes. We show that not only we are able to noninvasively observe all previously known forms of blastokinesis as an embryo develops, such as anatrepsis, katatrepsis, revolution, rotation and diapauses, and determine their precise occurring time or duration, but also discover an unreported rotation form we named "twist." In addition, with the OCT images we determined the exact occurring time of diapauses of the locusts from Tibetan plateau for the first time. Finally, we demonstrate that OCT systems can be used to rapidly capture the development defects of genetically modified embryos in which certain genes essential for embryonic development were suppressed by RNA interference. Our work shows that OCT is an enabling imaging tool with sufficient spatial resolution for the rapid evaluation of embryonic variations of small animals. [ABSTRACT FROM AUTHOR]