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Salvia daiguii Y.K.Wei & Y.B.Huang, a new species from China, is described. Salvia daiguii belongs to Salvia subg. Glutinaria (Raf.) G.X.Hu, C.L.Xiang & B.T.Drew, sect. Sobiso (Raf.) G.X.Hu, A.Takano & B.T.Drew, and is distinguished from morphologically similar species by differences in its habit, leaves, inflorescences and flowers. It has a narrow distribution in a karst region of Yongding District, Hunan Province, central China. A key to the Chinese species of section Sobiso is also presented.
Guangxi, a province in southwestern China, has the second highest reported number of HIV/AIDS cases in China. This study aimed to develop an accurate and effective model to describe the tendency of HIV and to predict its incidence in Guangxi. HIV incidence data of Guangxi from 2005 to 2016 were obtained from the database of the Chinese Center for Disease Control and Prevention. Long short-term memory (LSTM) neural network models, autoregressive integrated moving average (ARIMA) models, generalised regression neural network (GRNN) models and exponential smoothing (ES) were used to fit the incidence data. Data from 2015 and 2016 were used to validate the most suitable models. The model performances were evaluated by evaluating metrics, including mean square error (MSE), root mean square error, mean absolute error and mean absolute percentage error. The LSTM model had the lowest MSE when the N value (time step) was 12. The most appropriate ARIMA models for incidence in 2015 and 2016 were ARIMA (1, 1, 2) (0, 1, 2)12 and ARIMA (2, 1, 0) (1, 1, 2)12, respectively. The accuracy of GRNN and ES models in forecasting HIV incidence in Guangxi was relatively poor. Four performance metrics of the LSTM model were all lower than the ARIMA, GRNN and ES models. The LSTM model was more effective than other time-series models and is important for the monitoring and control of local HIV epidemics.
The feasibility of non-destructive detection and classification of in-shell insect-infested almonds was examined by using multispectral imaging (MSI) technology combined with chemometrics. Differentiation of reflectance spectral data between intact and insect-infested almonds was attempted by using analytical approaches based on principal component analysis and support vector machines, classification accuracy rates as high as 99.1% in the calibration set and 97.5% in the prediction set were achieved. Meanwhile, the in-shell almonds were categorized into three classes (intact, slightly infested and severely infested) based on the degree of damage caused by insect infestation and were characterized quantitatively by the analysis of shell/kernel weight ratio. A three-class model for the identification of intact, slightly infested and severely infested almonds yielded acceptable classification performance (95.6% accuracy in the calibration set and 93.3% in the prediction set). These results revealed that MSI technology combined with chemometrics may be a promising approach for the non-destructive detection of hidden insect damage in almonds and could be used for industrial applications.
Background: Longitudinal data on health-related quality of life (HRQOL) and fatigue in paediatric Duchenne muscular dystrophy (DMD) are limited. Recently, fatigue was reported to be the greatest predictor of poor HRQOL in paediatric DMD. Understanding the trajectory of HRQOL and its relationship with fatigue may facilitate the development of improved therapeutic strategies. Our objective was to describe three-year changes in HRQOL and fatigue in children with DMD. Methods: Patients identified via the Canadian Neuromuscular Disease Registry received mailed questionnaires (2013–2016). HRQOL was assessed using the PedsQLTM GCS and NMM domains, and fatigue was assessed using the MFS domain (patient- and parent-report). Mean three-year change in scores were computed. Pearson correlations were computed between three-year change in HRQOL and fatigue. Results: Mean decline in MFS scores for patient- and parent-reports were 1.03 and 1.19, respectively. Mean decline in GCS scores for patient- and parent-report were 1.75 and 4.13, respectively. Mean change in NMM scores for patient- and parent-report were 0.72 and -8.36, respectively. Change in MFS score was associated with changes in GCS (r=0.72, p<0.001) and NMM scores (r=0.84, p<0.001) by patient-report. Conclusions: Children with DMD experience worse fatigue and HRQOL over time. Parents perceive a greater decline in HRQOL over time compared to patients.
Background: Fatigue is frequent and disabling in adults with neuromuscular disorders, but not well characterized in paediatric neuromuscular disorders. Recently, fatigue was reported to be associated with poor health-related quality of life in children with Duchenne muscular dystrophy (DMD). Determinants of fatigue—a modifiable symptom—have not been studied in DMD. Our objective was to explore risk factors for fatigue in children with DMD. Methods: Patients aged 4–17 years identified via the Canadian Neuromuscular Disease Registry received mailed questionnaires. Fatigue was assessed using the PedsQLTM Multidimensional Fatigue Scale (patient- and parent-report). Standardized measures for depressive symptoms, sleep disturbances, functional ability and physical activity were used. Spearman’s correlations and Wilcoxon rank-sum tests were computed. Results: Of 194 eligible patients, 64 have responded to date. DMD patients reported greater fatigue than healthy controls from published data. Depressive symptoms were associated with greater fatigue, by patient-report (ρ=-0.44, P<0.001) and parent-report (ρ=-0.40, P=0.002). Sleep disturbances were associated with greater fatigue, by patient-report (ρ=-0.41, P=0.007) and parent-report (ρ=-0.51, P<0.001). Greater functional ability was associated with less fatigue, by parent-report (ρ=0.30, P=0.02). Physical activity and ambulatory status were not associated with fatigue. Conclusions: Fatigue is a significant issue in DMD. Depressive symptoms and sleep disturbances are associated with fatigue, warranting attention in therapeutic strategies to reduce fatigue.
Background: Fatigue was recently reported to be the largest contributor to poor health-related quality of life (HRQOL) in paediatric Duchenne muscular dystrophy (DMD). Additional studies are necessary to confirm the generalizability of this finding. Our objective was to explore the longitudinal relationship between fatigue and HRQOL in an additional cohort of DMD patients. Methods: We performed a secondary analysis of data from a clinical trial (NCT00592553), which enrolled patients with nonsense mutation DMD, aged 5–20 years, from 37 sites in 11 countries (N=174). Fatigue and HRQOL were assessed using the PedsQLTM Multidimensional Fatigue Scale and Generic Core Scales, respectively, by patient- and parent-report at baseline and over 48 weeks. Results: Patients reported greater fatigue than healthy controls from published data. There was no significant difference between patient- and parent-reported fatigue. Fatigue was significantly correlated with worse HRQOL at baseline, by patient-report (r=0.70, P<0.001) and parent-report (r=0.70, P<0.001); and at 48 weeks, by patient-report (r=0.79, P<0.001) and parent-report (r=0.74, P<0.001). Change in fatigue was significantly correlated with change in HRQOL over 48 weeks, by patient-report (r=0.64, P<0.001) and parent-report (r=0.67, P<0.001). Conclusions: Fatigue is a major contributor to HRQOL in DMD. The strong association between fatigue and HRQOL corroborates previous studies, and suggests that reducing fatigue may improve HRQOL.
We report a novel approach to the instantaneous photoinitiated synthesis of mixed anatase-rutile nanocrystalline TiO2 thin films with a three-dimensional nanostructure through pulsed white light irradiation of photosensitive Ti-organic precursor films. Pulsed photoinitiated pyrolysis accompanied by instantaneous self-assembly and crystallization occurred to form graphitic oxides-coated TiO2 nanograins. Subsequent pulsed light irradiation working as in situ pulsed photothermal treatment improved the crystalline quality of TiO2 film despite its low attenuation of light. The non-radiative recombination of photogenerated electrons and holes in TiO2 nanograins, coupled with inefficient heat dissipation due to low thermal conductivity, produces enough heat to provide the thermodynamic driving force for improving the crystalline quality. The graphitic oxides were reduced by pulsed photothermal treatment and can be completely removed by oxygen plasma cleaning. This photoinitiated nanofabrication technology opens a promising way for the low-cost and high-throughput manufacturing of nanostructured metal oxides as well as TiO2 nanocrystalline thin films.
The E2F transcription factor family is distributed widely in eukaryotes and has been well studied among mammals. In the present study, the E2F transcription factor 4 (E2F4) gene was isolated from fat bodies of Antheraea pernyi and sequenced. E2F4 comprised a 795 bp open reading frame encoding a deduced amino acid sequence of 264 amino acid residues. The recombinant protein was expressed in Escherichia coli (Transetta DE3), and anti-E2F4 antibodies were prepared. The deduced amino acid sequence displayed significant homology to an E2F4-like protein from Bombyx mori L. Quantitative real-time polymerase chain reaction analysis revealed that E2F4 expression was highest in the integument, followed by the fat body, silk glands, and haemocytes. The expression of E2F4 was upregulated in larvae challenged by bacterial (Escherichia coli, Micrococcus luteus), viral (nuclear polyhedrosis virus), and fungal (Beauveria bassiana) pathogens. These observations indicated that E2F4 is an inducible protein in the immune response of A. pernyi and probably in other insects.
Approximately half of the variation in wellbeing measures overlaps with variation in personality traits. Studies of non-human primate pedigrees and human twins suggest that this is due to common genetic influences. We tested whether personality polygenic scores for the NEO Five-Factor Inventory (NEO-FFI) domains and for item response theory (IRT) derived extraversion and neuroticism scores predict variance in wellbeing measures. Polygenic scores were based on published genome-wide association (GWA) results in over 17,000 individuals for the NEO-FFI and in over 63,000 for the IRT extraversion and neuroticism traits. The NEO-FFI polygenic scores were used to predict life satisfaction in 7 cohorts, positive affect in 12 cohorts, and general wellbeing in 1 cohort (maximal N = 46,508). Meta-analysis of these results showed no significant association between NEO-FFI personality polygenic scores and the wellbeing measures. IRT extraversion and neuroticism polygenic scores were used to predict life satisfaction and positive affect in almost 37,000 individuals from UK Biobank. Significant positive associations (effect sizes <0.05%) were observed between the extraversion polygenic score and wellbeing measures, and a negative association was observed between the polygenic neuroticism score and life satisfaction. Furthermore, using GWA data, genetic correlations of -0.49 and -0.55 were estimated between neuroticism with life satisfaction and positive affect, respectively. The moderate genetic correlation between neuroticism and wellbeing is in line with twin research showing that genetic influences on wellbeing are also shared with other independent personality domains.
Lipases are ubiquitous enzymes in nature, which play a crucial role in fat metabolism by catalyzing the hydrolysis of triacylglycerol to free fatty acids and glycerol. However, reports concerning insect lipase are rare. In this study, we studied the expression and activity of a lipase-related protein from Antheraea pernyi (ApLRP). Recombinant ApLRP was expressed in Escherichia coli cells and used to raise rabbit anti-ApLRP polyclonal antibodies. ApLRP mRNA and protein expression were abundant in the midgut and malpighian tubules, respectively. After challenge with four different microorganisms (E. coli, Beauveria bassiana, Micrococcus luteus and nuclear polyhedrosis virus), the expression levels of ApLRP mRNA in midgut were inducted significantly compared with the control. The different pathogens induced different ApLRP gene expression patterns. The optimum temperature and pH for the enzyme's activity were 35°C and 7.0, respectively. ApLRP activity was stimulated in the presence of Mg2+, Na+, Ca2+ and b-mercaptoethanol; while Zn2+, Cu2+ and Fe3+ inhibited its activity. Detergents such as SDS, glycerol and Tween-20 increased the lipase activity by 20–30%. Our results indicated that ApLRP might play an important role in the innate immunity of insects.
Van der Waals (vdW) heterojunctions consisting of vertically-stacked individual or multiple layers of two-dimensional layered semiconductors, especially the transition metal dichalcogenides (TMDs), show novel optoelectronic functionalities due to the sensitivity of their electronic and optical properties to strong quantum confinement and interfacial interactions. Here, monolayers of n-type MoSe2 and p-type Mo1−xWxSe2 are grown by vapor transport methods, then transferred and stamped to form artificial vdW heterostructures with strong interlayer coupling as proven in photoluminescence and low-frequency Raman spectroscopy measurements. Remarkably, the heterojunctions exhibit an unprecedented photoconductivity effect that persists at room temperature for several days. This persistent photoconductivity is shown to be tunable by applying a gate bias that equilibrates the charge distribution. These measurements indicate that such ultrathin vdW heterojunctions can function as rewritable optoelectronic switches or memory elements under time-dependent photo-illumination, an effect which appears promising for new monolayer TMDs-based optoelectronic devices applications.
Biased assessment of tillage impacts on soil organic carbon (SOC) sequestration are often associated with a lack of information on the initial level of SOC stocks. The present study reported the changes in SOC concentrations and stocks following 10-year different tillage practices relative to the initial SOC levels. The tillage trial included no tillage (NT), ridge tillage (RT) and mouldboard plough (MP) on a Black soil (Hapludolls) in Northeast China. Results showed that tillage, soil depth and time significantly affected SOC concentration and SOC stock. Tillage and crop residue retention had great impacts on the SOC concentrations in the top 0·1 m layer. Compared with MP and NT, RT resulted in higher SOC concentration and SOC stock in the plough layer (0–0·2 m), which became more obvious with time. The soil under NT and RT had higher stratification ratios (SR) of SOC (SR, the ratio of SOC concentration in 0–0·05 m to that in 0·1–0·2 m) than under MP. Significant positive and nearly identical linear relationships between the SR of SOC and the duration of tillage practices occurred for both NT and RT soils; the increased SR in NT resulted from both SOC increase in surface and SOC decrease in subsurface soils, but in RT, the increased SR was only from a substantial SOC increase in surface soil. Accordingly, the present study highlights that RT was more helpful than NT in carbon sequestration for the studied Black soil in Northeast China.
The search for alternative earth abundant semiconducting nanocrystals for sustainable energy applications has brought forth the need for nanoscale syntheses beyond bulk synthesis routes. Of particular interest are metal phosphides and derivative I–V–VI chalcogenides including copper phosphide (Cu3P) and copper thiophosphate (Cu3PS4). Herein, we report a one-pot, solution-based synthesis of Cu3P nanocrystals utilizing an in situ phosphorus source: phosphorus pentasulfide (P2S5) in trioctylphosphine. By injecting this phosphorus source into a copper solution in oleylamine, uniform and size controlled Cu3P nanocrystals with a phosphorous-rich surface are synthesized. The subsequent reaction of the Cu3P nanocrystals with decomposing thiourea forms nanoscale Cu3PS4 particles having p-type conductivity and an effective optical band gap of 2.36 eV. The synthesized Cu3PS4 produces a cathodic photocurrent during photoelectrochemical measurements, demonstrating its application as a light-absorbing material. Our process creates opportunities to explore other solution-based metal-phosphorus systems and their subsequent sulfurization for earth abundant, alternative energy materials.
The transmission of haemorrhagic fever with renal syndrome (HFRS) is deeply influenced by the reservoir and hantavirus prevalence rate. In this study, a surveillance on human HFRS cases, relative rodent abundance, and hantavirus infection prevalence was conducted in Shaanxi province, China, during 1984–2012. A generalized linear model with Poisson-distributed residuals and a log link was used to quantify the relationship between reservoir, virus and HFRS cases. The result indicated that there was a significant association of HFRS incidence with relative rodent density and the prevalence rate. This research provides evidence that the changes of infection prevalence in the reservoir could lead directly to the emergence of a new epidemic. It was concluded that the measurement of a number of these variables could be used in disease surveillance to give useful advance warning of potential disease epidemics.
In this work, sulfurizing metal precursors prepared by magnetron sputtering was applied in Cu2ZnSnS4 (CZTS) thin film fabrication. Three precursor structures, namely substrate/ Zn/(Cu&Sn), substrate/Zn/Cu/Sn/Cu and substrate/Zn/Sn/Cu, were compared for their synthesized CZTS film quality. It is notable that CZTS film made of the precursor structure of substrate/Zn/(Cu&Sn) has the best film quality with no obvious voids and biggest average grain size. When applying this precursor structure into device fabrication, a working CZTS device with an efficiency of 2.26% was made. The impact of metal precursors on the structural property of CZTS film were characterised by SEM, XRD, Raman and TEM. Thick MoS2 interfacial layer (∼200nm) between absorber and back Mo contact and ZnS formed in the front and back absorber regions are the possible reasons limiting short-circuit current and fill factor of the cell.
The focus of this work is on back contact improvement for sputtered CZTS thin film solar cells. Three methods have been investigated including a thin Ag coating, a thin ZnO coating on the Mo back contact and rapid thermal annealing of the back contact. All of these methods have been found to reduce defects such as voids as well as secondary phases at the back contact region and inhibit the formation of MoS2. Consequently all the mothods effectively enhances Voc, Jsc, FF and therefore efficiency significantly.
The heterojunctions formed between solution phase grown Cu2ZnSn(SxSe1- x)4 (CZTS,Se) and a number of important buffer materials including CdS, ZnS, ZnO, and In2S3, were studied using femtosecond ultraviolet photoemission spectroscopy (fs-UPS) and photovoltage spectroscopy. With this approach we extract the magnitude and direction of the CZTS,Se band bending, locate the Fermi level within the band gaps of absorber and buffer and measure the absorber/buffer band offsets under flatband conditions. We will also discuss two-color pump/probe experiments in which the band bending in the buffer layer can be independently determined. Finally, studies of the bare CZTS,Se surface will be discussed including our observation of mid-gap Fermi level pinning and its relation to Voc limitations and bulk defects.
Pesticide sorption by soil is among the most sensitive input parameters in many pesticide-leaching models. For many pesticides, organic matter is the most important soil constituent influencing pesticide sorption. Increased fertility, irrigation, and mowing associated with highly maintained turfgrass areas result in constant deposition of organic material, creating a soil system that can change drastically with time. Changes in soil characteristics could affect the environmental fate of pesticides applied to turfgrass systems of varying ages. Sorption characteristics of simazine and S-metolachlor were determined on five soils from bermudagrass systems of increasing ages (1, 4, 10, 21, and 99 yr) and compared to adjacent native pine and bare-ground areas. Surface soil (0 to 5 cm) and subsurface soil (5 to 15 cm) from all sites were air-dried and passed through a 4-mm sieve for separation from plant material. Using a batch-equilibrium method, sorption isotherms were determined for each soil. Data were fit to the Freundlich equation, and Kd (soil sorption coefficient) and Koc (organic carbon sorption coefficient) values were determined. Sorption and soil system age were directly related to organic matter content in the soil. Sorption of both herbicides increased with age of the soil system and was greatest on the surface soil from the oldest bermudagrass soil system. Herbicide sorption decreased at greater soil depths with lower organic matter. Greater amount of 14C–simazine sorbed to subsurface soil of the oldest turfgrass system compared to 14C–S-metolachlor. Results indicate that as bermudagrass systems age and accumulate higher organic matter levels increased herbicide sorption may decrease the leaching potential and bioavailability of simazine and S-metolachlor.