83 research outputs found

    Geographic and Climatic Attributions of Autumn Land Surface Phenology Spatial Patterns in the Temperate Deciduous Broadleaf Forest of China

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    Autumn vegetation phenology plays a critical role in identifying the end of the growing season and its response to climate change. Using the six vegetation indices retrieved from moderate resolution imaging spectroradiometer data, we extracted an end date of the growing season (EOS) in the temperate deciduous broadleaf forest (TDBF) area of China. Then, we validated EOS with the ground-observed leaf fall date (LF) of dominant tree species at 27 sites and selected the best vegetation index. Moreover, we analyzed the spatial pattern of EOS based on the best vegetation index and its dependency on geo-location indicators and seasonal temperature/precipitation. Results show that the plant senescence reflectance index-based EOS agrees most closely with LF. Multi-year averaged EOS display latitudinal, longitudinal and altitudinal gradients. The altitudinal sensitivity of EOS became weaker from 2000 to 2012. Temperature-based spatial phenology modeling indicated that a 1 K spatial shift in seasonal mean temperature can cause a spatial shift of 2.4–3.6 days in EOS. The models explain between 54% and 73% of the variance in the EOS timing. However, the influence of seasonal precipitation on spatial variations of EOS was much weaker. Thus, spatial temperature variation controls the spatial patterns of EOS in TDBF of China, and future temperature increase might lead to more uniform autumn phenology across elevations

    Sustainable protected cropping : a case study of seasonal impacts on greenhouse energy consumption during capsicum production

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    Sustainable food production in protected cropping is increasing rapidly in response to global climate change and population growth. However, there are significant knowledge gaps regarding energy consumption while achieving optimum environmental conditions for greenhouse crop production. A capsicum crop cultivated in a high-tech greenhouse facility in Australia was analysed in terms of relationships between key environmental variables and the comparative analysis of energy consumption during different seasons. We showed that daily energy consumption varied due to the seasonal nature of the external environment and maintenance of optimal growing temperatures. Total power consumption reported throughout the entire crop cycle for heating (gas hot water system) and cooling (pad and fan) was 12,503 and 5183 kWh, respectively; hence, heating consumed ca. 70% of the total energy requirement over the 8-month growing period (early spring to late autumn) in the greenhouse facility. Regressions of daily energy consumption within each season, designated either predominantly for heating or cooling, indicated that energy consumption was 14.62 kWh per 1 °C heating and 2.23 kWh per 1 °C cooling. Therefore, changing the planting date to late spring is likely to significantly reduce heating energy costs for greenhouse capsicum growers in Australia. The findings will provide useful guidelines to maximise the greenhouse production of capsicum with better economic return by taking into consideration the potential optimal energy saving strategy during different external environment conditions and seasons

    Energy minimisation in a protected cropping facility using multi-temperature acquisition points and control of ventilation settings

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    Energy management in protected cropping is critical due to the high cost of energy use in high-tech greenhouse facilities. The main purpose of this research was to investigate the optimal strategy to reduce cooling energy consumption, by regulating the settings (opening/closing) of either vents or curtains during the day, at the protected cropping facility at Western Sydney University. We measured daily changes in air temperature and energy consumption under four treatments (open/closed combinations of vents and shade screens) and developed an optimal cooling strategy for energy management using multi-temperature acquisition points at different heights within a greenhouse compartment. The optimal treatment (vents open/curtains closed) reduced energy load at the rooftop, thereby maintaining a desirable plant canopy temperature profile, and reducing cooling energy. Daily energy consumption was lowest for vents open/curtains closed (70.5 kWh) and highest for vents closed/curtains open (121 kWh). It was also found that delaying the operation of opening and closing of vents and curtains until the plant canopy temperature reached 25 ◦C reduced cooling energy consumption and decreased heating energy consumption in the morning (e.g., 08:00 to 10:00). The estimated savings of 1.83 kWh per 1 ◦C cooling between the optimal (vents open/curtains closed) and least optimal (vents closed/curtains open) conditions had the potential for significant energy savings at 494 kWh per ◦C over a crop cycle of nine months in warm weather conditions. However, selection of the optimal cooling strategy utilising control of vents and curtains must also account for the impact from other greenhouse environmental factors, including light, humidity, and CO2 concentration, which may be crop specific

    A novel cover material improves cooling energy and fertigation efficiency for glasshouse eggplant production

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    Glasshouses hold the potential to improve global food security, but high energy costs are an ongoing challenge in bringing them to the forefront of agriculture in warm climates. Here, the energy-saving potential of a ‘Smart Glass’ (SG), diffuse glass fitted with ULR-80 film which permits transmission of 85% of photosynthetically-active light and blocks heat-generating radiation, was characterised for a warm-climate glasshouse. Two consecutive 6-month trials of eggplant crops were grown in a high-tech glasshouse to compare SG to standard diffuse glass (control) in both cool and warm climate conditions. The SG reduced cooling energy use by 4.4% and fertigation demand by 29% in cooler months, and reduced cooling energy use by 4.4% and fertigation demand by 18% in warmer months. The SG did not significantly affect ventilation or heating energy use, but substantially reduced fruit yield. SG may be beneficial for reducing nutrient/water use alongside minor energy savings in commercial glasshouses. However, re-engineering the spectral characteristics of SG could improve eggplant fruit yield while maintaining reductions in energy, nutrient, and water use in the glasshouse

    Meta-analysis of Androgen Insensitivity in Preoperative Hormone Therapy in Hypospadias.

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    OBJECTIVE: To define androgen insensitivity prevalence in hypospadias patients treated with preoperative hormone therapy. MATERIALS AND METHODS: We searched databases that were published in English and Chinese up to September 10, 2014 for our studies. Eligibility criteria were pre-established. Title, abstract, and full-text screenings were conducted by 2 authors independently. Discrepancies were resolved by consensus. Quality assessment of included studies was completed. Meta-analysis was done when appropriate using R, version 3.1.1 for Windows. Heterogeneity among individual studies was tested using the Cochran chi-square Q test and quantified by calculating the I(2) index. RESULTS: Thirteen of 1278 publications met inclusion criteria and were incorporated into this study. Of 306 patients with preoperative hormone therapy, 25 displayed androgen resistance. Meta-analysis demonstrated that the random-effects model generates a pooled estimate of 7.14% (95% confidence interval [CI], 3.16%-15.31%), whereas the fixed-effect model provides an estimate of 14.61% (95% CI, 10.00%-20.85%). Heterogeneity among included studies was found above medium (I(2) = 67.1% [95% CI, 41.2%-81.6%]; P = .0003]. After exclusion of the heterogeneity, both random-effects and fixed-effect models produce a consistent pooled estimate of 6.95% (95% CI, 0%-47.8%). CONCLUSION: We have defined that the prevalence of androgen resistance in hypospadias is 7.14% (95% CI, 3.16%-15.31%). To distinguish isolated hypospadias from patients with androgen insensitivity syndrome, we recommend that androgen-resistant patients should be specifically targeted by molecularly focused diagnosis. Management strategies should include identification of mutations in the androgen receptor gene, timely surgery to repair hypospadias, and long-term follow-up of sexual function and fertility later in life

    ECG STUDY IN PATIENTS ON HIGH DOSE ANTIPSYCHOTICS

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    Objectives: There are many antipsychotic medications that have been shown to be associated with the prolongation of the rate-corrected QT (QTc) interval on the electrocardiogram (ECG). Studies have shown that QTc prolongation is associated with increased risk of arrhythmias and sudden cardiac death. This study aims to identify and study the risk profile of patients on high-dose antipsychotic and to examine the prevalence of rate and rhythm abnormalities, in particular, QTc prolongation. We hope that this study could throw a light on current practice patterns and also could potentially guide us towards safe practice in the future. Methods: We recruited 37 adult outpatients who are on high-dose antipsychotic from the 3 outpatient clinics of the Institute of Mental Health in Singapore. Baseline characteristics risk profiling was performed to identify their pre-existing risk, including checks on Calcium, Potassium and Magnesium levels to rule out confounders. 12 lead ECG was done and reviewed manually by our resident physician. Results: It showed that rate abnormality was detected in 8 patients (22%) and QTc interval prolongation was detected in nearly 12 patients (32.4%) but of those only 3 patients had significantly prolonged QT interval needing the primary treating team to review their psychopharmacology regime. Conclusion: QTc Prolongation was positively linked with a number of cardiovascular risk factors

    Novel transcriptome networks are associated with adaptation of capsicum fruit development to a light-blocking glasshouse film

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    Light-blocking films (LBFs) can contribute to significant energy savings for protected cropping via altering light transmitting, such as UVA, photosynthetically active radiation, blue and red spectra affecting photosynthesis, and capsicum yield. Here, we investigated the effects of LBF on orange color capsicum (O06614, Capsicum annuum L.) fruit transcriptome at 35 (mature green) and 65 (mature ripe) days after pollination (DAP) relative to untreated control in a high-technology glasshouse. The results of targeted metabolites showed that LBF significantly promotes the percentage of lutein but decreased the percentage of zeaxanthin and neoxanthin only at 35 DAP. At 35 DAP, fruits were less impacted by LBF treatment (versus control) with a total of 1,192 differentially expressed genes (DEGs) compared with that at 65 DAP with 2,654 DEGs. Response to stress and response to light stimulus in biological process of Gene Ontology were found in 65-DAP fruits under LBF vs. control, and clustering analysis revealed a predominant role of light receptors and phytohormone signaling transduction as well as starch and sucrose metabolism in LBF adaptation. The light-signaling DEGs, UV light receptor UVR8, transcription factors phytochrome-interacting factor 4 (PIF4), and an E3 ubiquitin ligase (COP1) were significantly downregulated at 65 DAP. Moreover, key DEGs in starch and sucrose metabolism (SUS, SUC, and INV), carotenoid synthesis (PSY2 and BCH1), ascorbic acid biosynthesis (VTC2, AAO, and GME), abscisic acid (ABA) signaling (NCED3, ABA2, AO4, and PYL2/4), and phenylpropanoid biosynthesis (PAL and DFR) are important for the adaptation of 65-DAP fruits to LBF. Our results provide new candidate genes for improving quality traits of low-light adaptation of capsicum in protected cropping

    Severe Pneumonia Caused by Coinfection With Influenza Virus Followed by Methicillin-Resistant Staphylococcus aureus Induces Higher Mortality in Mice

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    Background: Coinfection with influenza virus and bacteria is a major cause of high mortality during flu pandemics. Understanding the mechanisms behind such coinfections is of utmost importance both for the clinical treatment of influenza and the prevention and control of epidemics.Methods: To investigate the cause of high mortality during flu pandemics, we performed coinfection experiments with H1N1 influenza virus and Staphylococcus aureus in which mice were infected with bacteria at time points ranging from 0 to 7 days after infection with influenza virus.Results: The mortality rates of mice infected with bacteria were highest 0–3 days after infection with influenza virus; lung tissues extracted from these co-infected mice showed higher infiltrating cells and thicker lung parenchyma than lung samples from coinfected mice in which influenza virus was introduced at other times and sequences. The levels of interferon (IFN)-γ, tumor necrosis factor (TNF)-α, interleukin (IL)-8, and IL-6 in the 0–3 day coinfected group were significantly higher than those in the other groups (p < 0.01), as were the mRNA levels of IFN-γ, IL-6, and TNF-α. Coinfection with influenza virus and S. aureus led to high mortality rates that are directly dependent on the sequence and timing of infection by both pathogens. Moreover, coinfection following this particular schedule induced severe pneumonia, leading to increased mortality.Conclusions: Our data suggest that prevention of bacterial co-infection in the early stage of influenza virus infection is critical to reducing the risk of clinical mortality

    Review of solid–liquid phase change materials and their encapsulation technologies

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    Various types of solid–liquid phase change materials (PCMs) have been reviewed for thermal energy storage applications. The review has shown that organic solid–liquid PCMs have much more advantages and capabilities than inorganic PCMs but do possess low thermal conductivity and density as well as being flammable. Inorganic PCMs possess higher heat storage capacities and conductivities, cheaper and readily available as well as being non-flammable, but do experience supercooling and phase segregation problems during phase change process. The review has also shown that eutectic PCMs have unique advantage since their melting points can be adjusted. In addition, they have relatively high thermal conductivity and density but they possess low latent and specific heat capacities. Encapsulation technologies and shell materials have also been examined and limitations established. The morphology of particles was identified as a key influencing factor on the thermal and chemical stability and the mechanical strength of encapsulated PCMs. In general, in-situ polymerization method appears to offer the best technological approach in terms of encapsulation efficiency and structural integrity of core material. There is however the need for the development of enhancement methods and standardization of testing procedures for microencapsulated PCMs

    A crowdsourced analysis to identify ab initio molecular signatures predictive of susceptibility to viral infection

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    The response to respiratory viruses varies substantially between individuals, and there are currently no known molecular predictors from the early stages of infection. Here we conduct a community-based analysis to determine whether pre- or early post-exposure molecular factors could predict physiologic responses to viral exposure. Using peripheral blood gene expression profiles collected from healthy subjects prior to exposure to one of four respiratory viruses (H1N1, H3N2, Rhinovirus, and RSV), as well as up to 24 h following exposure, we find that it is possible to construct models predictive of symptomatic response using profiles even prior to viral exposure. Analysis of predictive gene features reveal little overlap among models; however, in aggregate, these genes are enriched for common pathways. Heme metabolism, the most significantly enriched pathway, is associated with a higher risk of developing symptoms following viral exposure. This study demonstrates that pre-exposure molecular predictors can be identified and improves our understanding of the mechanisms of response to respiratory viruses
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