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Microbial systems appear to exhibit a relatively high switching capacity of moving back and forth among few dominant communities (taxon memberships). While this switching behavior has been mainly attributed to random environmental factors, it remains unclear the extent to which internal community dynamics affect the switching capacity of microbial systems. Here, we integrate ecological theory and empirical data to demonstrate that structured community transitions increase the dependency of future communities on the current taxon membership, enhancing the switching capacity of microbial systems. Following a structuralist approach, we propose that each community is feasible within a unique domain in environmental parameter space. Then, structured transitions between any two communities can happen with probability proportional to the size of their feasibility domains and inversely proportional to their distance in environmental parameter space—which can be treated as a special case of the gravity model. We detect two broad classes of systems with structured transitions: one class where switching capacity is high across a wide range of community sizes and another class where switching capacity is high only inside a narrow size range. We corroborate our theory using temporal data of gut and oral microbiota (belonging to class 1) as well as vaginal and ocean microbiota (belonging to class 2). These results reveal that the topology of feasibility domains in environmental parameter space is a relevant property to understand the changing behavior of microbial systems. This knowledge can be potentially used to understand the relevant community size at which internal dynamics can be operating in microbial systems. [ABSTRACT FROM AUTHOR]

RNA molecules serve a wide range of functions that are closely linked to their structures. The basic structural units of RNA consist of single- and double-stranded regions. In order to carry out advanced functions such as catalysis and ligand binding, certain types of RNAs can adopt higher-order structures. The analysis of RNA structures has progressed alongside advancements in structural biology techniques, but it comes with its own set of challenges and corresponding solutions. In this review, we will discuss recent advances in RNA structure analysis techniques, including structural probing methods, X-ray crystallography, nuclear magnetic resonance, cryo-electron microscopy, and small-angle X-ray scattering. Often, a combination of multiple techniques is employed for the integrated analysis of RNA structures. We also survey important RNA structures that have been recently determined using various techniques. [ABSTRACT FROM AUTHOR]

Background: Gay, bisexual, and other men who have sex with men (MSM) are at high risk of acquiring human immunodeficiency virus (HIV). Taking pre-exposure prophylaxis (PrEP) daily reduces the risk of acquiring HIV through sexual contact by up to 99%. This study aimed to assess the prevalence of PrEP awareness and use, and the associated factors among HIV-negative, sexually active MSM in Dallas, Texas. Methods: Data from 406 HIV-negative, sexually active MSM recruited through venue-based sampling in 2017 and obtained from the National HIV Behavioral Surveillance project in Dallas, Texas, were analyzed. We used descriptive and inferential statistics that included bivariate and multivariate regression models to explore the associations between self-reported PrEP awareness and use, and the sociodemographic characteristics and high-risk sexual behaviors. Results: Prevalence of PrEP awareness and use in the past 12 months were 83.7% and 18.2%, respectively. PrEP awareness was significantly (p<0.05) less common among Black and Hispanic/Latino MSM (80.0% and 77.2% respectively) and among those with a high school diploma/General Educational Development (GED) or less (65.3%) or five or less male sexual partners in the past 12 months (80.4%). It was also lower among those with a household income of less than $20,000 (55.4%) and persons experiencing homelessness (57.7%) or incarceration (61.3%). PrEP use was significantly (p<0.05) lower among Black and Hispanic/Latino MSM (11.7% and 13.8% respectively) as well as those without health insurance (12.3%), with a high school diploma/GED or less (9.2%), and with household income lower than $20,000 (7.1%). PrEP awareness was 13% less common among Black MSM (adjusted prevalence ratio [aPR]=0.87, 95% confidence interval [CI]: 0.79-0.97) and 15% less common among Hispanic MSM (aPR=0.85, 95% CI: 0.78-0.93) compared to White MSM. In contrast, PrEP awareness (aPR: 1.12, 95% CI: 1.02-1.22) and use (aPR:2.02, 95% CI: 1.42-2.88) were significantly (p<0.05) associated with participation in HIV behavioral interventions. Conclusion: The positive association of HIV behavioral interventions with both PrEP awareness and use suggests that this approach may enhance PrEP rollout in Dallas and also serve as a model for statewide campaigns in the MSM communities. In addition, efforts to increase PrEP awareness and use should target Black and Hispanic MSM and MSM with lower socioeconomic status (SES). [ABSTRACT FROM AUTHOR]

Introduction: There is a lot of evidence that suggests that microRNAs (miRs) play an imperative role in the pathogenesis of polycystic ovary syndrome (PCOS). This study was designed to decipher the role of miR-125b in PCOS pathogenesis.Material and methods: Expression analysis of miR-125b was determined by real-time quantitative polymerase chain reaction and the KGN ovarian granulosa cell viability was examined by CCK-8 assay. DAPI assay and flow cytometry were carried out for the detection of apoptosis and cell cycle distribution respectively. Protein levels were checked by immunoblotting.Results: The miR-125b transcript levels were considerably high in polycystic ovaries and ovarian granulosa KGN cells. The inhibition of miR-125b expression decreased the viability of the KGN cells by arresting the cells at the G2/M check point. Target Scan analysis revealed cyclin B1 as the target of miR-125b and suppression of miR-125b caused considerable up-regulation of cyclin B1 expression. Like miR-125b inhibition, cyclin B1 silencing also inhibited the KGN cell viability via G2/M arrest. Ectopic expression of miR-125b was unable to nullify the effects of cyclin-B silencing on KGN cell viability but the overexpression of cyclin B1 nullified the effects of the miR-125b suppression on KGN cell proliferation.Conclusions: Since miR-125b controls the proliferation rate of granulosa cells in polycystic ovaries, it might be addressed as a potential therapeutic target for PCOS patients. [ABSTRACT FROM AUTHOR]

A comprehensive understanding of the thermal runaway (TR) and combustion characteristics of lithium-ion batteries (LIBs) is vital for safety protection of LIBs. LIBs are often subjected to abuse through the coupling of various thermal trigger modes in large energy storage application scenarios. In this paper, we systematically investigated the TR and combustion characteristics of heating + overcharge and heating + short circuit at different temperatures and compared them with individual heating, overcharge, and short circuit. Additionally, we analyzed the TR and combustion hazards of different thermal triggering modes using Analytic Hierarchy Process (AHP). The results show that heating + overcharge has a shorter time of safety valve opening and TR , a lower thermal runaway temperature, a higher peak heat release rate (HRR), and is more hazardous than heating and overcharge. Compared with heating, heating + short circuit shortens safety valve opening time and increases peak HRR ; versus short circuit, heating + short circuit lowers TR temperature and TR time, enhances peak HRR , and causes a higher hazard. The AHP analysis indicates that the TR temperature and fire growth index are the most critical parameters and that heating + overcharge has the biggest TR and combustion hazards; besides, heating + short circuit exists higher TR risk and hazards than short circuit and greater combustion risks and hazards than heating. The research findings can provide valuable guidance for protecting and preventing energy storage LIBs TR. • Investigate the behavior of thermal runaway and combustion properties of LIBs with varying coupled trigger modes. • The external short circuit shortens the valve opening time and increases the peak heat release rate. • The greatest risk and hazard of thermal runaway and combustion occurs when heating and overcharging are combined. [ABSTRACT FROM AUTHOR]

In situ temperature measurements in laser-heated diamond-anvil cells (LHDACs) are among the most fundamental experiments undertaken in high-pressure science. Despite its importance, few efforts have been made to examine the alteration of thermal radiation spectra of hot samples by wavelength-dependent absorption of the sample itself and temperature gradients within the sample and their influence on temperature measurements while laser heating. In this study, we take (Mg, Fe)O ferropericlase as an example to evaluate the effects of these two factors. Iron-rich ferropericlase shows strong wavelength-dependent absorption in the wavelength range used to determine temperature, which, together with temperature gradients can account for largely aliased apparent temperatures in some experiments obtained by Wien fitting of detected thermal radiation intensities (e.g., an offset of ~700K for a 3300K melting temperature). In general, wavelength-dependent absorption and temperature gradients of samples are two key factors to consider in order to rigorously constrain temperatures, which have been largely ignored in previous LHDAC studies. [ABSTRACT FROM AUTHOR]

Carotenoids are important natural pigments that give bright colors to plants. The difference in the accumulation of carotenoids is one of the key factors in the formation of various colors in carrot taproots. Carotenoid cleavage dioxygenases (CCDs), including CCD and 9-cis epoxycarotenoid dioxygenase, are the main enzymes involved in the cleavage of carotenoids in plants. Seven CCD genes have been annotated from the carrot genome. In this study, through expression analysis, we found that the expression level of DcCCD4 was significantly higher in the taproot of white carrot (low carotenoid content) than orange carrot (high carotenoid content). The overexpression of DcCCD4 in orange carrots caused the taproot color to be pale yellow, and the contents of α- and β-carotene decreased sharply. Mutant carrot with loss of DcCCD4 function exhibited yellow color (the taproot of the control carrot was white). The accumulation of β-carotene was also detected in taproot. Functional analysis of the DcCCD4 enzyme in?vitro showed that it was able to cleave α- and β-carotene at the 9, 10 (9', 10') double bonds. In addition, the number of colored chromoplasts in the taproot cells of transgenic carrots overexpressing DcCCD4 was significantly reduced compared with that in normal orange carrots. Results showed that DcCCD4 affects the accumulation of carotenoids through cleavage of α- and β-carotene in carrot taproot. [ABSTRACT FROM AUTHOR]

Using genetic mutations to study protein functions in vivo is a central paradigm of modern biology. Single-domain camelid antibodies generated against GFP have been engineered as nanobodies or GFP-binding proteins (GBPs) that can bind GFP as well as some GFP variants with high affinity and selectivity. In this study, we have used GBP-mCherry fusion protein as a tool to perturb the natural functions of a few kinetochore proteins in the fission yeast Schizosaccharomyces pombe. We found that cells simultaneously expressing GBP-mCherry and the GFP-tagged inner kinetochore protein Cnp1 are sensitive to high temperature and microtubule drug thiabendazole (TBZ). In addition, kinetochore-targeted GBP-mCherry by a few major kinetochore proteins with GFP tags causes defects in faithful chromosome segregation. Thus, this setting compromises the functions of kinetochores and renders cells to behave like conditional mutants. Our study highlights the potential of using GBP as a general tool to perturb the function of some GFP-tagged proteins in vivo with the objective of understanding their functional relevance to certain physiological processes, not only in yeasts, but also potentially in other model systems. [ABSTRACT FROM AUTHOR]

Periodontitis is an infection-driven inflammatory disease with a complex etiology that is associated with spontaneous tooth loosening. The remediation of periodontitis requires the activation of osteogenesis and regeneration of the lost tissue that is currently not possible through existing clinical practice. The present study has examined the effects of Astragaloside I on the osteogenesis and osteogenic differentiation of periodontal ligament stem cells. The results show increased cell viability and alkaline phosphatase activity in the periodontal ligament stem cells by Astragaloside I treatment. Astragaloside I stimulated the expression of ALP, RUNX2, ß-catenin, and OPN in PDLSCs suggesting that Astragaloside I enhances osteoblastic differentiation by modulating Wnt/ß-catenin signaling pathway. Further support for involvement of the Wnt/ß-catenin signaling pathway comes from the reversal of Astragaloside I stimulation by inhibition of this pathway by a specific inhibitor. In summary the results presented here suggest Astragaloside I as a promising candidate drug for bone remodeling and periodontal tissue engineering. [ABSTRACT FROM AUTHOR]

Ultrafine RDX (cyclotrimethylene trinitramine, C3H6N6O6) particles were prepared by ultrasonic assisted spray method, and the RDX-based composites with various polymer binders were obtained by water suspension method. The binders in composites are as follows: ACM (AR-12, AR-14, AR-71), Viton A and F2602. The binding energies between crystal surfaces of RDX and the binders were calculated, which show that the binding energies of RDX and ACM are higher than those of RDX and other binders. Then the crystal morphologies, crystal structures, thermal decomposition properties and mechanical sensitivities of raw RDX, ultrafine RDX and the RDX-based composites were characterized. Finally, the static mechanical properties of the RDX-based composites were tested and the detonation pressures of samples was calculated. The results show that there are different degrees of improvement in the combination properties of RDX after coating by the polymers, and AR-71 is the most suitable binder for coating RDX. [ABSTRACT FROM AUTHOR]

Ultrafine RDX (cyclotrimethylene trinitramine, C3H6N6O6) particles were prepared by ultrasonic assisted spray method, and the RDX-based composites with various polymer binders were obtained by water suspension method. The binders in composites are as follows: ACM (AR-12, AR-14, AR-71), Viton A and F2602. The binding energies between crystal surfaces of RDX and the binders were calculated, which show that the binding energies of RDX and ACM are higher than those of RDX and other binders. Then the crystal morphologies, crystal structures, thermal decomposition properties and mechanical sensitivities of raw RDX, ultrafine RDX and the RDX-based composites were characterized. Finally, the static mechanical properties of the RDX-based composites were tested and the detonation pressures of samples was calculated. The results show that there are different degrees of improvement in the combination properties of RDX after coating by the polymers, and AR-71 is the most suitable binder for coating RDX. [ABSTRACT FROM AUTHOR]

A sample including 935 blazars with 415 Flat Spectrum Radio Quasars (FSRQs) and 520 BL Lac objects (BL Lacs) (233 HBLs (High synchrotron peak frequency BL Lacs), 144 IBLs (Intermediate synchrotron peak frequency BL Lacs), and 143 LBLs (Low synchrotron peak frequency BL Lacs)) is selected in Fermi 3FGL catalogue. The correlations between two flux densities of the radio 1.4 GHz and γ -ray at 0.1, 0.3, 1, 3, and 10 GeV are investigated for the samples of all blazars, FSRQs, BL Lacs, and subclasses of HBLs and LBLs, respectively. Results show that there are strong positive correlations between the two flux densities, with the correlation coefficients r = 0.48 ∼ 0.81 , and the chance probabilities p all less than 10 − 4. The correlation coefficient has different trends with the change of γ -ray emission frequency for different blazar samples, and the average correlation coefficients for all the samples at five respective bands decrease with the increase of γ -ray frequency. Therefore, with the increase of γ -ray frequency, the dominant mechanism of γ -ray radiation of blazar is changing, and at the same frequency the dominant mechanism is different for different samples. The γ -ray emission of HBLs may be mainly dominated by the synchrotron self-Compton, while the other mechanisms are responsible for the γ -ray emissions of LBLs. The origin of γ -ray in FSRQs is more complex than that of BL Lacs. [ABSTRACT FROM AUTHOR]

Objective: To explore relationships between PET/CT characteristics of cold-activated brown adipose tissue (BAT), measures of adiposity and metabolic markers. Methods: We conducted a post-hoc analysis of a study which utilized PET/CT to characterize BAT. 25 men ages 18-24 (BMI 19.4 to 35.9 kg/m²) were studied. Fasting blood samples were collected. Body composition was measured using DXA. An individualized cooling protocol was utilized to activate BAT prior to imaging with PET/CT. Results: There was an inverse relationship between fasting serum glucose and BAT volume (r = -0.40, p = 0.048). A marginally significant inverse relationship was also noted between fasting glucose and total BAT activity (r = -0.40, p = 0.05). In addition, a positive correlation was observed between serum FGF21 and SUVmax (r = 0.51, p = 0.01). No significant correlations were noted for measures of BAT activity or volume and other indicators of adiposity or glucose metabolism. Conclusions: The presence of active BAT may be associated with lower fasting glucose in young men. BAT activity may also be correlated with levels of FGF21, suggesting that BAT may lower glucose levels via an FGF21 dependent pathway. Further studies are needed to clarify mechanisms by which BAT may impact glucose metabolism. [ABSTRACT FROM AUTHOR]

Legume-rhizobia symbiosis is a time-limited process due to the onset of senescence, which results in the degradation of host plant cells and symbiosomes. A number of transcription factors, proteases, and functional genes have been associated with nodule senescence; however, whether other proteases or transcription factors are involved in nodule senescence remains poorly understood. In this study, we identified an early nodule senescence mutant in Medicago truncatula, denoted basic helix-loop-helix transcription factor2 (bhlh2), that exhibits decreased nitrogenase activity, acceleration of plant programmed cell death (PCD), and accumulation of reactive oxygen species (ROS). The results suggest that MtbHLH2 plays a negative role in nodule senescence. Nodules of wild-type and bhlh2-TALEN mutant plants at 28 d postinoculation were used for transcriptome sequencing. The transcriptome data analysis identified a papain-like Cys protease gene, denoted MtCP77, that could serve as a potential target of MtbHLH2. Electrophoretic mobility shift assays and chromatin immunoprecipitation analysis demonstrated that MtbHLH2 directly binds to the promoter of MtCP77 to inhibit its expression. MtCP77 positively regulates nodule senescence by accelerating plant PCD and ROS accumulation. In addition, the expression of MtbHLH2 in the nodules gradually decreased from the meristematic zone to the nitrogen fixation zone, whereas the expression of MtCP77 showed enhancement. These results indicate that MtbHLH2 and MtCP77 have opposite functions in the regulation of nodule senescence. These results reveal significant roles for MtbHLH2 and MtCP77 in plant PCD, ROS accumulation, and nodule senescence, and improve our understanding of the regulation of the nodule senescence process. [ABSTRACT FROM AUTHOR]

With the rapid development of modern digital systems, the high-density requirements for on-chip systems are becoming higher and higher. However, as the resources of various on-chip systems increase, the utilisation rate of the resources of the system is declining; Dynamic reconfigurable technology based on FPGA reconfigures all resources or partial resources within the FPGA, and then achieve switching of different logic functions, but does not stop the operation of the FPGA; This article conducts an in-depth study of the FPGA dynamic reconfigurable technology at first, then combines FPGA, PowerPC and CPLD into one system to verify dynamic reconfigurable technology. [ABSTRACT FROM AUTHOR]

The electronic spin transition of iron has been shown to strongly affect many thermoelastic properties of the host mineral. However, the response of melting temperatures to the spin transition remains largely unexplored. Here, we study the melting of lower mantle minerals, ferropericlase and bridgmanite, using Lindemann's Law. This empirical law predicts a negligible melting temperature depression for Earth-relevant bridgmanite but a substantial depression for Earth-relevant ferropericlase across the spin transition of iron, consistent with extant experimental results. This melting depression can be explained within the framework of Lindemann's Law for a Debye-like solid. The transition of iron from high- to low-spin configuration reduces the molar volume and the bulk modulus of the crystal, leading to a decrease in Debye frequency and consequently lowering the melting temperature. Thermodynamically, the melting depression likely derives from a more negative Margules parameter for a liquid mixture of high- and low-spin end-members as compared to that of a solid mixture. This melting depression across the spin transition of iron may be the process responsible for the formation of a deep molten layer during the crystallization of a magma ocean in the past, and a reduced viscosity layer at present. [ABSTRACT FROM AUTHOR]

Seismic observations suggest that the uppermost region of Earth's liquid outer core is buoyant, with slower velocities than the bulk outer core. One possible mechanism for the formation of a stably stratified layer is immiscibility in molten iron alloy systems, which has yet to be demonstrated at core pressures. We find immiscibility between liquid Fe-Si and Fe-Si-O persisting to at least 140 GPa through a combination of laser-heated diamond-anvil cell experiments and first-principles molecular dynamics simulations. High-pressure immiscibility in the Fe-Si-O system may explain a stratified layer atop the outer core, complicate differentiation and evolution of the deep Earth, and affect the structure and intensity of Earth's magnetic field. Our results support silicon and oxygen as coexisting light elements in the core and suggest that SiO2 does not crystallize out of molten Fe-Si-O at the core-mantle boundary. [ABSTRACT FROM AUTHOR]

The protective effect of resveratrol (RSV), a stimulator of the silent mating type information regulation 2 homolog (SIRT1), on the neurotoxicity of rat brain induced by chronic fluorosis was investigated. Thirty-two Sprague-Dawley (SD) rats were divided randomly into four groups: (i) a control group; (ii) a RSV treatment group; (iii) a fluoride-exposed group (50 ppm F- in drinking water); and (iv) a fluoride plus RSV group. The experimental period was 7 months. The protein levels of SIRT1 in the cortex and the hippocampus of the rat brains were determined by Western blotting, the SOD activity and the MDA content in the brains by biochemical methods, and the 8-OHdG content by ELISA. The spatial learning ability and the memory of the rats was examined by the Morris Water Maze test. The results showed chronic fluorosis caused changes to the brains of the rats with a reduced SIRT1 protein, elevated MDA and 8-OHdG contents, inhibited SOD activity, and, in addition, decreased learning and memory. Interestingly, RSV pretreatment attenuated the reduced SIRT1, the raised level of oxidative stress, and the lowered ability for learning and memory resulting from the chronic fluorosis. The results indicate that RSV may have a neuroprotective effect on fluoride toxicity. [ABSTRACT FROM AUTHOR]

The levels of DNA methylation were analyzed in the peripheral blood cells of children, with or without skeletal fluorosis, in the area of the coal-burning type of endemic fluorosis in Guizhou Province of China. Whole genome DNA methylation 450 K BeadChip and pyrosequencing were performed, and the main function and pathway of differential methylation genes determined by GO analysis and the KEGG database. The results showed that 15 differential hypermethylated and 22 hypomethylated CpG sites were determined in the children with skeletal fluorosis, which involved 29 known genes, as compared to controls. The majority of the differentially methylated CpG loci resided in the gene body. Further, the GO analysis and the KEGG database for the pathway analysis indicated that these differential genes are mainly involved in synapse maturation, axon, neuron projection membrane, transcription coactivator activity, and the Notch signaling pathway. Pyrosequencing analysis showed that the gene MAML2 was hypomethylated in the children with skeletal fluorosis, which is the same as the chip result. A change concerning genome-wide DNA methylation in the children with skeletal fluorosis was also found. The results suggest that the alteration of the hypomethylated MAML2 gene may play an important role in the occurrence and development of skeletal fluorosis. [ABSTRACT FROM AUTHOR]

Tissue repair is a highly dynamic process, and the immediate onset of acute inflammation has been considered necessary for repair. Pore-forming proteins are important, both in pathogen invasion and host immunity. However, their roles in wound healing and tissue repair are unclear. βγ-crystallin fused aerolysin-like protein (a-subunit) and trefoil factor (β-subunit) complex (βγ-CAT) is a complex of a bacterial pore-forming toxin aerolysin-like protein and trefoil factor identified in the frog Bombina maxima. In this study, we established mouse cutaneous wound models to explore the effects of βγ-CAT on skin wound healing. βγ-CAT accelerated the healing of full-thickness wounds by improving re-epithelialization. This complex relieved dermal edema and promoted scarless healing. βγ-CAT treatment resulted in a rapid release of IL-1β, which initiated an acute inflammation response in the early stage of healing. Meanwhile, the expression levels of TGF-β1, VEGF, and bFGF and the recruitment of M2 macrophages around the wound significantly increased after βγ-CAT treatment. βγ-CAT protected skin wounds against methicillin-resistant Staphylococcus aureus by improving neutrophil recruitment at the site of the wound. Overall, our results suggest that βγ-CAT can promote tissue repair and protect skin wounds against antibiotic-resistant bacterial infection by triggering the acute inflammatory response. This is the first example that aerolysin-like pore-forming proteins widely existing in plants and animals may act in wound healing and tissue repair. [ABSTRACT FROM AUTHOR]

DOES NOT MAKE INFECTION 2 (MtDMI2) is a Leu rich repeat-type receptor kinase required for signal transduction in the Medicago truncatula/Sinorhizobium meliloti symbiosis pathway. However, the mechanisms through which MtDMI2 participates in nodulation homeostasis are poorly understood. In this study, we identified MtPUB2--a novel plant U-box (PUB)-type E3 ligase--and showed that it interacts with MtDMI2. MtDMI2 and MtPUB2 accumulation were shown to be similar in various tissues. Roots of plants in which MtPUB2 was silenced by RNAi (MtPUB2-RNAi plants) exhibited impaired infection threads, fewer nodules, and shorter primary root lengths compared to those of control plants transformed with empty vector. Using liquid chromatography-tandem mass spectrometry, we showed that MtDMI2 phosphorylates MtPUB2 at Ser-316, Ser-421, and Thr-488 residues. When MtPUB2-RNAi plants were transformed with MtPUB2S421D, which mimics the phosphorylated state, MtDMI2 was persistently ubiquitinated and degraded by MtPUB2S421D, resulting in fewer nodules than observed in MtPUB2/MtPUB2-RNAi-complemented plants. However, MtPUB2S421A/MtPUB2-RNAi-complemented plants showed no MtPUB2 ubiquitination activity, and their nodulation phenotype was similar to that of MtPUB2-RNAi plants transformed with empty vector. Further studies demonstrated that these proteins form a negative feedback loop of the prey (MtDMI2)-predator (MtPUB2) type. Our results suggest that the MtDMI2-MtPUB2 negative feedback loop, which displays crosstalk with the long-distance autoregulation of nodulation via MtNIN, plays an important role in nodulation homeostasis. [ABSTRACT FROM AUTHOR]

Current research aims to investigate the influence of calcination temperature on the pozzolanic activity of the waste kaolin and the impact of calcination products on Portland cement hydration. The raw material with approximately 85 % kaolinite was calcined to temperatures ranging between 500 and 1000 °C. The clay and its calcined products were characterized by TGA-DTA, SEM-EDS, XRD, FT-IR and BET. The pozzolanic activity of the calcined products was assessed by electrical conductivity test and compressive strength in mortars with 30 % substitution of Portland cement. The effect of calcined products on Portland cement hydration was characterized by XRD and SEM. The results showed that the calcination temperature had an important influence on mineral phase transition and the pozzolanic activity of calcined products. The degree of disorder and pozzolanic activity of calcined products at 800 °C was the highest at temperatures ranging from 500 and 1000 °C. The impact of calcined products on the hydration of blended systems was a combination of a filler effect at early ages and the pozzolanic reaction at later. The experimental results indicated that calcined products of waste kaolin constituted a potential source of high reactivity pozzolanic materials. [ABSTRACT FROM AUTHOR]

Niche partitioning and sequence evolution drive genomic and phenotypic divergence, which ultimately leads to bacterial diversification. This study investigated the genomic composition of two Shewanella baltica clades previously identified through multilocus sequencing typing and recovered from the redox transition zone in the central Baltic Sea. Comparative genomic analysis revealed significantly higher interclade than intraclade genomic dissimilarity and that a subset of genes present in clade A were associated with potential adaptation to respiration of sulfur compounds present in the redox transition zone. The transcriptomic divergence between two representative strains of clades A and D, OS185 and OS195, was also characterized and revealed marked regulatory differences. We found that both the transcriptional divergence of shared genes and expression of strain-specific genes led to differences in regulatory patterns between strains that correlate with environmental redox niches. For instance, under anoxic conditions of respiratory nitrate ammonification, OS185--the strain isolated from a nitrate-rich environment--upregulated nearly twice the number of shared genes upregulated by OS195--the strain isolated from an H2S-containing anoxic environment. Conversely, OS195 showed stronger induction of strain-specific genes, especially those associated with sulfur compound respiration, under thiosulfate-reducing conditions. A positive association between the level of transcriptional divergence and the level of sequence divergence for shared genes was also noted. Our results provide further support for the hypothesis that genomic changes impacting transcriptional regulation play an important role in the diversification of ecologically distinct populations. [ABSTRACT FROM AUTHOR]

The purpose of the study was to investigate the role of the signal transducer and activator of transcription 3 (STAT3), signal transduction protein in regulating the biological characteristics of stem cells in cervical carcinoma. Overexpressed plasmid of STAT3 was constructed and used to transfect SiHa into cervical carcinoma cells. STAT3-targeted specific siRNA was designed and produced. The effects of STAT3 upregulation (or inhibition) on the expression of NANOG, OCT4 and SOX2 markers of stem cells were measured, using western blot analysis and RT-qPCR. In addition, the tumor sphere experiment was also conducted to detect the formation of tumor spheres after the intervention of expression of STAT3 and the expression of STAT3, NANOG, OCT4 and SOX2 was detected in 35 cases of cervical carcinoma tissues and 31 cases of normal cervical tissues using immunohistochemistry. We determined whether the STAT3 overexpression plasmid was successfully constructed using enzyme digestion, PCR for bacterium solution, western blot analysis and RT-qPCR and found that the plasmid met the requirements of subsequent procedures. Compared with the empty plasmid group and STAT3 low expression group, the mRNA and protein expression of markers of stem cells, OCT4, SOX2 and NANOG were significantly elevated in the STAT3 overexpression group with statistically significant differences (P<0.05), the formation ratio of tumor spheres in the STAT3 overexpression group was also significantly higher than those in the other two groups (P<0.05). The positive expression of STAT3, OCT4, NANOG and SOX2 in the cervical squamous carcinoma group was also markedly higher than that in the chronic cervicitis group (P<0.05). This study led us to a conclusion that STAT3 can regulate the characteristics of stem cells in cervical carcinoma, and STAT3, NANOG, OCT4 and SOX2 are highly expressed in cervical squamous carcinoma, thus able to promote the progression of cervical carcinoma. [ABSTRACT FROM AUTHOR]

Seismic anisotropy has been documented in many portions of the lowermost mantle, with particularly strong anisotropy thought to be present along the edges of large low shear velocity provinces (LLSVPs). The region surrounding the Pacific LLSVP, however, has not yet been studied extensively in terms of its anisotropic structure. In this study, we use seismic data from southern Peru, northern Bolivia and Easter Island to probe lowermost mantle anisotropy beneath the eastern Pacific Ocean, mostly relying on data from the Peru Lithosphere and Slab Experiment and Central Andean Uplift and Geodynamics of High Topography experiments. Differential shear wave splitting measurements from phases that have similar ray paths in the upper mantle but different ray paths in the lowermost mantle, such as SKS and SKKS, are used to constrain anisotropy in D". We measured splitting for 215 same station-event SKS-SKKS pairs that sample the eastern Pacific LLSVP at the base of the mantle. We used measurements of splitting intensity(SI), a measure of the amount of energy on the transverse component, to objectively and quantitatively analyse any discrepancies between SKS and SKKS phases. While the overall splitting signal is dominated by the upper-mantle anisotropy, a minority of SKS-SKKS pairs (~10 per cent) exhibit strongly discrepant splitting between the phases (i.e. the waveforms require a difference in SI of at least 0.4), indicating a likely contribution from lowermost mantle anisotropy. In order to enhance lower mantle signals, we also stacked waveforms within individual subregions and applied a waveform differencing technique to isolate the signal from the lowermost mantle. Our stacking procedure yields evidence for substantial splitting due to lowermost mantle anisotropy only for a specific region that likely straddles the edge of Pacific LLSVP. Our observations are consistent with the localization of deformation and anisotropy near the eastern boundary of the Pacific LLSVP, similar to previous observations for the African LLSVP. [ABSTRACT FROM AUTHOR]

Bacterial competition for resources is common in nature but positive interactions among bacteria are also evident. We speculate that the structural complexity of substrate might play a role in mediating bacterial interactions. We tested the hypothesis that the frequency of antagonistic interactions among lignocellulolytic bacteria is reduced when complex polysaccharide is the main carbon source compared to when a simple sugar such as glucose is available. Results using all possible pairwise interactions among 35 bacteria isolated from salt marsh detritus showed that the frequency of antagonistic interactions was significantly lower on carboxymethyl cellulose (CMC)-xylan medium (7.8%) than on glucose medium (15.5%). The two interaction networks were also different in their structures. Although 75 antagonistic interactions occurred on both media, there were 115 that occurred only on glucose and 20 only on CMC-xylan, indicating that some antagonistic interactions were substrate specific. We also found that the frequency of antagonism differed among phylogenetic groups. Gammaproteobacteria and Bacillus sp. were the most antagonistic and they tended to antagonize Bacteroidetes and Actinobacteria, the most susceptible groups. Results from the study suggest that substrate complexity affects how bacteria interact and that bacterial interactions in a community are dynamic as nutrient conditions change. [ABSTRACT FROM AUTHOR]

With the intensive development of large-scale livestock industry, the gas emissions from livestock farms were identified as a major problem. Many greenhouse gases and odorous gases are generated from animal exhalation, ruminant fermentation, livestock waste, and other factors. Considering the environmental impact brought by pollutant gas emissions, it is important to determine how it contributes to total emissions accurately in order to minimize it. This article gives a comprehensive overview over the non-spectroscopic techniques and spectroscopic techniques applied to air quality assessment in livestock. In addition, this review summarizes interferences in the detection process, emphasizing different interference reduction approaches for improving the performance of current detection technologies used in livestock farms. [ABSTRACT FROM PUBLISHER]

Abstract: This paper reports on efforts to enhance the photovoltaic performance of textured silicon solar cells through the application of a layer of Eu-doped silicate phosphor with particles of various dimensions using the spin-on film technique. We examined the surface profile and dimensions of the Eu-doped phosphors in the silicate layer using optical microscopy with J-image software. Optical reflectance, photoluminescence, and external quantum efficiency were used to characterize the luminescent downshifting (LDS) and light scattering of the Eu-doped silicate phosphor layer. Current density-voltage curves under AM 1.5G simulation were used to confirm the contribution of LDS and light scattering produced by phosphor particles of various dimensions. Experiment results reveal that smaller phosphor particles have a more pronounced effect on LDS and a slight shading of incident light. The application of small Eu-doped phosphor particles increased the conversion efficiency by 9.2% (from 12.56% to 13.86%), far exceeding the 5.6% improvement (from 12.54% to 13.32%) achieved by applying a 250 nm layer of SiO2 and the 4.5% improvement (from 12.37% to 12.98%) observed in cells with large Eu-doped phosphor particles. [ABSTRACT FROM AUTHOR]

Nitrogen (N) is an important macronutrient for plant growth and development, but the regulatory mechanism of volatile compounds in response to N deficiency is not well understood, especially in cucumber, which consumes excessive N during growth. In this study, the major volatile compounds from cucumber leaves subjected to N deficiency were analyzed by GC-MS. A total of 24 volatile components were identified including 15 aldehydes, two ketones, two alkenes, and five other volatile compounds in 9930 leaves. Principal component analysis using volatile compounds from cucumber leaves provided good separation between N-sufficient and N-deficient treatments. The main volatiles in cucumber leaves were found to be C6 and C9 aldehydes, especially (E)-2-hexanal and (E,Z)-2,6-nonadienal. (E)-2-hexanal belonged to the C6 aldehyde and was the most abundant compound, whereas (E,Z)-2,6-nonadienal was the chief component of C9 aldehydes. During N-deficient treatment, short-chain volatile content was significantly improved at 5 day, other volatiles displayed significant reduction or no significantly changes in all sampling points. Improvement of short-chain volatiles was confirmed in the six other inbred lines at 5 day after N-deficient treatments. The expression analysis of 12 cucumber LOX genes and two HPL genes revealed that CsLOX19, CsLOX20, and CsLOX22 had common up-regulated expression patterns in response to N-deficient stress in most inbred lines; meanwhile, most sample points of CsHPL1 also had significant up-regulated expression patterns. This research focused on the relationship between volatiles in cucumber and different nitrogen environments to provide valuable insight into the effect of cultivation and management of the quality of cucumber and contributes to further research on volatile metabolism in cucumber. [ABSTRACT FROM AUTHOR]

Background: Liver disease is a major cause of death worldwide. Orthotropic liver transplantation (OLT) represents the only effective treatment for patients with liver failure, but the increasing demand for organs is unfortunately so great that its application is limited. Hepatocyte transplantation is a promising alternative to OLT for the treatment of some liver-based metabolic disorders or acute liver failure. Unfortunately, the lack of donor livers also makes it difficult to obtain enough viable hepatocytes for hepatocyte-based therapies. Currently, a fundamental solution to this key problem is still lacking. Here we show a novel non-transgenic protocol that facilitates the rapid generation of functional induced hepatocytes (iHeps) from human adipose-derived stem cells (hADSCs), providing a source of available cells for autologous hepatocytes to treat liver disease. Methods: We used collagenase digestion to isolate hADSCs. The surface marker was detected by flow cytometry. The multipotential differentiation potency was detected by induction into adipocytes, osteocytes, and chondrocytes. Passage 3-7 hADSCs were induced into iHeps using an induction culture system composed of small molecule compounds and cell factors. Results: Primary cultured hADSCs presented a fusiform or polygon appearance that became fibroblast-like after passage 3. More than 95 % of the cells expressed the mesenchymal cell markers CD29, CD44, CD166, CD105, and CD90. hADSCs possessed multipotential differentiation towards adipocytes, osteocytes, and chondrocytes. We rapidly induced hADSCs into iHeps within 10 days in vitro; the cellular morphology changed from fusiform to close-connected cubiform, which was similar to hepatocytes. After induction, most of the iHeps co-expressed albumin and alpha-1 antitrypsin; they also expressed mature hepatocyte special genes and achieved the basic functions of hepatocyte. Moreover, iHep transplantation could improve the liver function of acute liver-injured NPG mice and prolong life. Conclusions: We isolated highly purified hADSCs and rapidly induced them into functional hepatocyte-like cells within 10 days. These results provide a source of available cells for autologous hepatocytes to treat liver disease. [ABSTRACT FROM AUTHOR]

Primary ovarian leiomyosarcoma (POLMS) is a rare disease. To the best of our knowledge, only 72 cases, including the present case, have been reported in the English literature, while synchronous POLMS and fibroma in a single ovary have not previously been reported at all. In the present study, a 46-year-old premenopausal woman was diagnosed with a mass in the left ovary in 2005. A total of 5 years after the diagnosis of this mass, the patient was admitted to hospital exhibiting lower abdominal pain, and two masses were observed in the left ovary. An exploratory laparoscopy was performed. Frozen section analysis led to a diagnosis of fibroma. Furthermore, the observed second mass was hypothesized to be a malignant form of the original fibroma. A hysterectomy and bilateral salpingo-oophorectomy were performed. Pathological reports following surgery revealed concurrent stage Ic POLMS and fibroma in the left ovary. A total of 13 months after the initial surgery, recurrent leiomyosarcoma was detected. Although the patient underwent multiple cytoreductive surgeries and chemotherapy cycles, as well as interstitial brachytherapy and conventional therapy, a poor state of health ensued. Due to the rarity of POLMS, particularly in combination with ovarian fibroma, the current report presents a detailed overview of the literature and discusses a number of histogenetic and clinical issues. [ABSTRACT FROM AUTHOR]

In this paper, cathode spot plasma jet (CSPJ) rotation and cathode spots behavior subjected to two kinds of large diameter axial magnetic field (AMF) electrode (cup-shaped and coil-shaped) are studied and analyzed based on experiments. The influence of gap distances on the CSPJ rotational behavior is analyzed. Experimental results show that CSPJ rotational phenomena extensively exist in the vacuum interrupters, and CSPJ rotational direction is along the direction of composite magnetic field (mainly the combination of the axial and azimuthal components). For coil-shaped and cup-shaped AMF electrodes, the rotational or inclination phenomena before the current peak value are much more significant than that after current peak value (for the same arc current), which is related to the larger ratio of azimuthal magnetic field Bt and AMF Bz (Bt/Bz). With the increase of the gap distance, the AMF strength decreases, when the arc current is kept as constant, the azimuthal magnetic field is kept invariable, the ratio between azimuthal magnetic field and AMF is increased, which results in the increase of rotational effect. For cathode spots motion, compared with cup-shaped electrode, coil-shaped electrode has the inverse AMF direction. The Robson drift direction of cathode spots of coil-shaped electrode is opposite to that of cup-shaped electrode. With the increase of gap distance, the Robson angle is decreased, which is associated with the reduced AMF strength. Erosion imprints of anode and cathode are also related to the CSPJ rotational phenomena and cathode spots behavior. The noise of arc voltage in the initial arcing stage is related to the weaker AMF. [ABSTRACT FROM AUTHOR]

In this research, drawing vacuum arc (VA) experiments were conducted using composite contacts under currents ranging from 5 kA to 20 kA root mean square (rms). The new type of contact comprised an axial magnetic field (AMF) configuration and a transverse magnetic field (TMF) configuration. The TMF plate was in the center, surrounded by the AMF plate. The contact generated both AMFs and TMFs simultaneously. VA appearances and arc voltages were recorded, and the VA was modeled as a conductor for electromagnetic force analysis in ANSYS software. The results showed that the coaxiality of operating mechanisms significantly influenced arc behavior just as the arc was ignited. When arc brightness did not increase after ignition, there was a voltage drop accompanied with diffusion of the VA. As to VA development, when an arc was ignited on an AMF plate, it spread on the plate and rotated. Over time the arc current increased, the constricting arc forms, and the arc column rotated on the TMF plate under the action of Ampere's force. With regard to the influence of a magnetic field on a VA at different stages, in the initial drawing arc stage the TMF was dominant, and the arc started to rotate under the action of Ampere's force. Afterwards, the AMF was dominant, with a steadily burning arc. As for contact melting, in the initial arcing period, a contracted short arc caused severe melting and erosion of the contact plate. When the ignition spot or root was close to the slot of plate, the electromagnetic force pushed the arc toward slot and contact edge, resulting in local erosion of the slot region. [ABSTRACT FROM AUTHOR]

Surface modification has long beenof great interest to impartdesired functionalities to the bioimplants. However, due to the limitationsof recent technologies in surface modification, it is highly desirableto explore novel protocols, which can advantageously and efficientlyendow the inert material surfaces with versatile biofunctionalities.Herein, to achieve versatile and rapid postfunctionalization of polymericmembrane, we demonstrate a new strategy for the fabrication of β-cyclodextrin(β-CD) modified host membrane substrate that can recognize aseries of well-designed guest macromolecules. The surface assemblyprocedure was driven by the host–guest interaction betweenadamantane (Ad) and β-CD. β-CD immobilized host membranewas fabricated via two steps: (1) epoxy groups enriched poly(ethersulfone) (PES) membrane was first prepared via in situcross-linking polymerization and subsequently phase separation;(2) mono-6-deoxy-6-ethylenediamine-β-CD (EDA-β-CD)was then anchored onto the surface of the epoxy functionalized PESmembrane to obtain PES-CD. Subsequently, three types of Ad-terminatedpolymers, including Ad-poly(styrenesulfonate-co-sodiumacrylate) (Ad-PSA), Ad-methoxypoly(ethylene glycol) (Ad-PEG), andAd-poly(methyl chloride-quaternized 2-(dimethylamino)ethyl methacrylate(Ad-PMT), were separately assembled onto the β-CD immobilizedsurfaces to endow the membranes with anticoagulant, antifouling, andantibacterial capability, respectively. Activated partial thromboplastintime (APTT), thrombin time (TT), and prothrombin time (PT) measurementswere carried out to explore the anticoagulant activity. The antifoulingcapability was evaluated via protein adsorption and platelet adhesionmeasurements. Moreover, Staphyllococcous aureus(S. aureus) was selected as model bacteriato evaluate the antibacterial ability of the functionalized membranes.The results indicated that well-regulated blood compatibility, antifoulingcapability, and bactericidal activity could be achieved by the proposedrapid postfunctionalization on polymeric membranes. This approachof versatile and rapid postfunctionalization is promising for thepreparation of multifunctional polymeric membrane materials to meetwith various demands for the further applications. [ABSTRACT FROM AUTHOR]

With the high resolution of optical data and the lack of weather effects of passive microwave data, we developed an algorithm to map daily cloud-free fractional snow cover (FSC) based on the Moderate Resolution Imaging Spectroradiometer (MODIS) standard daily FSC product, the Advanced Microwave Scanning Radiometer (AMSR2) snow water equivalent (SWE) product and digital elevation data. We then used the algorithm to produce a daily cloud-free FSC product with a resolution of 500 m for regions in China. In addition, we produced a high-resolution FSC map using a Landsat 8 Operational Land Imager (OLI) image as a true value to test the accuracy of the cloud-free FSC product developed in this study. The analysis results show that the daily cloud-free FSC product developed in this study can completely remove clouds and effectively improve the accuracy of snow area monitoring. Compared to the true value, the mean absolute error of our product is 0.20, and its root mean square error is 0.29. Thus, the synthesized product in this study can improve the accuracy of snow area monitoring, and the obtained snow area data can be used as reliable input parameters for hydrological and climate models. The land cover type and terrain factors are the main factors that limit the accuracy of the daily cloud-free FSC product developed in this study. These limitations can be further improved by improving the accuracy of the MODIS standard snow product for complicated underlying surfaces. [ABSTRACT FROM AUTHOR]

The aim of this study was to prepare a liposomal delivery system for rapamycin and study its in vitro release characteristics. The results may provide a foundation for the further development of a liposomal delivery system for rapamycin and the establishment of a new active treatment method targeted towards the cellular components of atherosclerotic plaques. The ethanol injection method was used to prepare rapamycin-containing liposomes. The formulation was optimized by orthogonal design, and the degree of rapamycin release by the liposomes was measured by the reverse dialysis method. Orthogonal testing showed that the optimum formulation had a phospholipid concentration of 4%, a phospholipid-cholesterol mass ratio of 8:1, a drug-lipid mass ratio of 1:20 and an aqueous phase pH of 7.4. Rapamycin-containing liposomes with an encapsulation efficiency of 82.11±2.13% were prepared, and the in vitro release of rapamycin from the liposomes complied with a first-order kinetic equation. In conclusion, the formulation was optimized, the prepared liposomes had a high rapamycin encapsulation rate and good reproducibility, and their in vitro release had a certain delayed-release effect. [ABSTRACT FROM AUTHOR]

Let q be an odd prime. Let c > 1 and t be positive integers such that qt + 1 = 2c². Using elementary method and a result due to Ljunggren concerning the Diophantine equation xn-1/x-1 = y², we show that the Diophantine equation x² + qm = c2n has the only positive integer solution (x, m, n) = (c² - 1, t, 2). As applications of this result some new results on the Diophantine equation x² + qm = cn and the Diophantine equation x² + (2c - 1)m = cn are obtained. In particular, we prove that Terai's conjecture is true for c = 12,24. Combining this result with Terai's results we conclude that Terai's conjecture is true for 2 ≥ c ≥ 30 [ABSTRACT FROM AUTHOR]

Recent data suggest possible net transport of urinary constituents across mammalian urinary tract epithelia (urothelia). To evaluate the effect of animal hydration status on such transport, we instilled urine collected during 2-day water deprivation, water loading, or ad libitum water intake into isolated in situ bladder(s) of groups of rats undergoing one of the same three hydration states. After 1-h bladder dwell, we retrieved the urine and measured differences in volume and solute concentrations between instilled and retrieved urine. We previously reported results regarding changes in urine volume and net urea and creatinine transport and herein report the results of net urinary sodium, potassium, and chloride transport in the same animals. During water-loading conditions, urinary concentrations of Na, K, and Cl rose 4.9 (30.7%), 2.6 (16.5%), and 6.0 meq/l (26.8%), respectively, indicating urothelial secretion into urine. During ad libitum water intake, urinary K and Cl concentrations fell 33.6 (14.8%) and 28.4 meq/l (12%), respectively (Na did not change), and during water deprivation urine Na, K, and Cl concentrations fell dramatically by 53.2 (18.6%), 159.4 (34.6%) and 133.7 meq/l (33.8%), respectively, reflecting urothelial reabsorption of each ion. For each ionic species, two factors independently influenced transport: instilled urinary ion concentration and animal hydration state. These results demonstrate significant regulated ion transport across mammalian urothelia, support the notion that lower urinary tract modifies final urine, and suggest that the lower urinary tract may play a role in local and whole animal solute homeostasis. [ABSTRACT FROM AUTHOR]

Understandinghow kinetics in the unfolded state affects protein folding is a fundamentallyimportant yet less well-understood issue. Here we employ three differentmodels to analyze the unfolded landscape and folding kinetics of theminiprotein Trp-cage. The first is a 208 μs explicit solventmolecular dynamics (MD) simulation from D. E. Shaw Research containingtens of folding events. The second is a Markov state model (MSM-MD)constructed from the same ultralong MD simulation; MSM-MD can be usedto generate thousands of folding events. The third is a Markov statemodel built from temperature replica exchange MD simulations in implicitsolvent (MSM-REMD). All the models exhibit multiple folding pathways,and there is a good correspondence between the folding pathways fromdirect MD and those computed from the MSMs. The unfolded populationsinterconvert rapidly between extended and collapsed conformationson time scales ≤40 ns, compared with the folding time of ∼5μs. The folding rates are independent of where the folding isinitiated from within the unfolded ensemble. About 90% of the unfoldedstates are sampled within the first 40 μs of the ultralong MDtrajectory, which on average explores ∼27% of the unfoldedstate ensemble between consecutive folding events. We clustered thefolding pathways according to structural similarity into “tubes”,and kinetically partitioned the unfolded state into populations thatfold along different tubes. From our analysis of the simulations anda simple kinetic model, we find that, when the mixing within the unfoldedstate is comparable to or faster than folding, the folding waitingtimes for all the folding tubes are similar and the folding kineticsis essentially single exponential despite the presence of heterogeneousfolding paths with nonuniform barriers. When the mixing is much slowerthan folding, different unfolded populations fold independently, leadingto nonexponential kinetics. A kinetic partition of the Trp-cage unfoldedstate is constructed which reveals that different unfolded populationshave almost the same probability to fold along any of the multiplefolding paths. We are investigating whether the results for the kineticsin the unfolded state of the 20-residue Trp-cage is representativeof larger single domain proteins. [ABSTRACT FROM AUTHOR]

The uncertain position of lung tumor during radiotherapy compromises the treatment effect. To effectively control respiratory motion during radiotherapy of lung cancer without any side effects, a novel control scheme, hypnosis, has been introduced in lung cancer treatment. In order to verify the suggested method, six volunteers were selected with a wide range of distribution of age, weight, and chest circumference. A set of experiments have been conducted for each volunteer, under the guidance of the professional hypnotist. All the experiments were repeated in the same environmental condition. The amplitude of respiration has been recorded under the normal state and hypnosis, respectively. Experimental results show that the respiration motion of volunteers in hypnosis has smaller and more stable amplitudes than in normal state. That implies that the hypnosis intervention can be an alternative way for respiratory control, which can effectively reduce the respiratory amplitude and increase the stability of respiratory cycle. The proposed method will find useful application in image-guided radiotherapy. [ABSTRACT FROM AUTHOR]

Although mammalian urinary tract epithelium (urothelium) is generally considered impermeable to water and solutes, recent data suggest that urine constituents may be reabsorbed during urinary tract transit and storage. To study water and solute transport across the urothelium in an in vivo rat model, we instilled urine (obtained during various rat hydration conditions) into isolated in situ rat bladders and, after a 1-h dwell, retrieved the urine and measured the differences in urine volume and concentration and total quantity of urine urea nitrogen and creatinine between instilled and retrieved urine in rat groups differing by hydration status. Although urine volume did not change >1.9% in any group, concentration (and quantity) of urine urea nitrogen in retrieved urine fell significantly (indicating reabsorption of urea across bladder urothelia), by a mean of 18% (489 mg/dl, from an instilled 2,658 mg/dl) in rats receiving ad libitum water and by a mean of 39% (2,544 mg/dl, from an instilled 6,204 mg/dl) in water-deprived rats, but did not change (an increase of 15 mg/dl, P = not significant, from an instilled 300 mg/dl) in a water-loaded rat group. Two separate factors affected urea nitrogen reabsorption rates, a urinary factor related to hydration status, likely the concentration of urea nitrogen in the instilled urine, and a bladder factor(s), also dependent on the animal's state of hydration. Urine creatinine was also absorbed during the bladder dwell, and hydration group effects on the concentration and quantity of creatinine reabsorbed were qualitatively similar to the hydration group effect on urea transport. These findings support the notion(s) that urinary constituents may undergo transport across urinary tract epithelia, that such transport may be physiologically regulated, and that urine is modified during transit and storage through the urinary tract. [ABSTRACT FROM AUTHOR]

The conformational dynamics in the flaps of HIV-1 protease plays a crucial role in the mechanism of substrate binding. We develop a kinetic network model, constructed from detailed atomistic simulations, to determine the kinetic mechanisms of the conformational transitions in HIV-1 PR. To overcome the time scale limitation of conventional molecular dynamics (MD) simulations, our method combines replica exchange MD with transition path theory (TPT) to study the diversity and temperature dependence of the pathways connecting functionally important states of the protease. At low temperatures the large-scale flap opening is dominated by a small number of paths; at elevated temperatures the transition occurs through many structurally heterogeneous routes. The expanded conformation in the crystal structure 1TW7 is found to closely mimic a key intermediate in the flap-opening pathways at low temperature. We investigated the different transition mechanisms between the semi-open and closed forms. The calculated relaxation times reveal fast semi-open ↔ closed transitions, and infrequently the flaps fully open. The ligand binding rate predicted from this kinetic model increases by 38-fold from 285 to 309 K, which is in general agreement with experiments. To our knowledge, this is the first application of a network model constructed from atomistic simulations together with TPT to analyze conformational changes between different functional states of a natively folded protein. [ABSTRACT FROM AUTHOR]

Purpose/Objectives: To describe the current state of the science on secondary lymphedema in patients with head and neck cancer.Data Sources: Published journal articles and books and data from the National Cancer Institute, the American Cancer Society, and other healthcare-related professional association Web sites.Data Synthesis: Survivors of head and neck cancer may develop secondary lymphedema as a result of the cancer or its treatment. Secondary lymphedema may involve external (e.g., submental area) and internal (e.g., laryngeal, pharyngeal, oral cavity) structures. Although lymphedema affects highly visible anatomic sites (e.g., face, neck), and profoundly influences critical physical functions (e.g., speech, breathing, swallowing, cervical range of motion), research regarding this issue is lacking. Studies are needed to address a variety of vital questions, including incidence and prevalence, optimal measurement techniques, associated symptom burden, functional loss, and psychosocial impact.Conclusions: Secondary lymphedema in patients with head and neck cancer is a significant but understudied issue.Implications for Nursing: A need exists to systematically examine secondary lymphedema related to treatment for head and neck cancer and address gaps in the current literature, such as symptom burden, effects on body functions, and influences on quality of life. Oncology nurses and other healthcare professionals should have empirical evidence to help them manage lymphedema after head and neck cancer treatment. [ABSTRACT FROM AUTHOR]

In the kinetic theory of dislocations, the evolution of the dislocation density is governed by a hierarchy of kinetic equations in which a number of source terms associated with cross-slip and short-range (junction and annihilation) reactions are included. In the present study, these sources are modeled by considering cross-slip and short-range reactions to be stochastic processes in time. The concepts of marked point process and time series are used to analyze the statistical properties of these processes in both time and frequency domains. The statistical data required to perform this analysis has been obtained for copper crystals using the method of dislocation dynamics simulation. The temporal correlations and correlation times of cross-slip and short-range reactions have been computed. It is found that the correlation time for cross-slip is the largest of all correlation times and, as such, it is considered here to be the coarse graining time-scale in continuum dislocation dynamics. Using this mesoscopic time-scale, the continuous source terms in the kinetic equations of dislocations have been modeled and their rate parameters are determined. [ABSTRACT FROM AUTHOR]

This paper compares the characteristics of an RF microelectromechanical systems (MEMS) capacitive switch with a molybdenum membrane versus that of a switch with similar construction but with an aluminum membrane. In comparison, the molybdenum switch exhibits a significantly reduced sensitivity to ambient temperature change so that its pull-in voltage varies by less than 0.035 V/°C. In addition, large-signal RF performance of the switches was compared under both continuous wave and pulse conditions. The results show that under large RF signals, the self-biasing effect is exacerbated by the self-heating effect and the self-heating effect is in turn amplified by nonuniform current and temperature distributions on the membrane. Measurements of both molybdenum and aluminum switches demonstrate a hot-switched power-handling capacity of approximately 600 mW. Since aluminum has been used as a membrane material for over a decade while molybdenum is new, the above results indicate that molybdenum is a promising membrane material for RF MEMS capacitive switches. [ABSTRACT FROM AUTHOR]

We propose a path for extending the technology roadmap when currently considered technology boosters (e.g., strain, high-κ/metal gate) reach their limits and physical gate length can no longer be effectively scaled down. By judiciously engineering the device parasitic resistance and parasitic capacitance, and considering the impact of the interconnect wiring capacitance, we propose scenarios of selective device structure scaling that will enable technology scaling and contacted gate pitch scaling for several generations beyond the currently perceived limits. [ABSTRACT FROM AUTHOR]

A temperature-dependent RF large-signal model is constructed by modifying the Verilog-A code of the Angelov model for unique characteristics of GaN MOSHFETs. Different from the previously reported EEHEMT-based model, the present electro-thermal model can fit the temperature effects on threshold shift and transconductance degradation, the drain current in the linear region, and the gate capacitance near the cutoff region. As the result, the power, gain, efficiency, linearity, drain current, and gate current of both Class-A and Class-AB amplifiers are accurately simulated over a wide range of input powers, matching impedances, and ambient temperatures. [ABSTRACT FROM AUTHOR]

Carbon-nanotube (CNT) field-effect transistors (CNFETs) are promising extensions to silicon CMOS. Simulations show that CNFET inverters fabricated with a perfect CNFET technology have 13 times better energy delay product compared with 32-nm silicon CMOS inverters. The following two fundamental challenges prevent the fabrication of CNFET circuits with the aforementioned advantages: 1) misaligned and mispositioned CNTs and 2) metallic CNTs. Misaligned and mispositioned CNTs can cause incorrect functionality. This paper presents a technique for designing arbitrary logic functions using CNFET circuits that are guaranteed to implement correct functions even in the presence of a large number of misaligned and mispositioned CNTs. Experimental demonstration of misaligned and mispositioned CNT-immune logic structures is also presented. [ABSTRACT FROM AUTHOR]

This paper proposes a novel nonparametric approach for the modeling and analysis of electricity price curves by applying the manifold learning methodology—locally linear embedding (LLE). The prediction method based on manifold learning and reconstruction is employed to make short-term and medium-term price forecasts. Our method not only performs accurately in forecasting one-day-ahead prices, but also has a great advantage in predicting one-week-ahead and one-month-ahead prices over other methods. The forecast accuracy is demonstrated by numerical results using historical price data taken from the Eastern U.S. electric power markets. [ABSTRACT FROM AUTHOR]

Aim: We previously showed that cellular repressor of E1A-stimulated genes (CREG) is up-regulated during serum starvation-induced vascular smooth muscle cell (SMC) differentiation. The aim of this study was to determine the role of CREG in maintaining the quiescent, differentiated phenotype of SMCs both in culture and in balloon-injured rat carotid artery. [ABSTRACT FROM PUBLISHER]