Precipitation variation: a key factor regulating plant diversity in semi-arid livestock grazing lands.

Livestock presence impacts plant biodiversity (species richness) in grassland ecosystems, yet extent and direction of grazing impacts on biodiversity vary greatly across inter-annual periods. In this study, an 8-year (2014-2021) grazing gradient experiment with sheep was conducted in a semi-arid grassland to investigate the impact of grazing under different precipitation variability on biodiversity. The results suggest no direct impact of grazing on species richness in semi-arid Stipa grassland. However, increased grazing indirectly enhanced species richness by elevating community dominance (increasing the sheltering effect of Stipa grass). Importantly, intensified grazing also regulates excessive community biomass resulting from increased inter-annual wetness (SPEI), amplifying the positive influence of annual humidity index on species richness. Lastly, we emphasize that, in water-constrained grassland ecosystems, intra-annual precipitation variability (PCI) was the most crucial factor driving species richness. Therefore, the water-heat synchrony during the growing season may alleviate physiological constraints on plants, significantly enhancing species richness as a result of multifactorial interactions. Our study provides strong evidence for how to regulate grazing intensity to increase biodiversity under future variable climate patterns. We suggest adapting grazing intensity according to local climate variability to achieve grassland biodiversity conservation.

Application Value of Cardiometabolic Index for the Screening of Obstructive Sleep Apnea with or Without Metabolic Syndrome.

Background: Obstructive sleep apnea (OSA) is a common chronic disease with various comorbidities. The cardiometabolic index (CMI) reflects visceral fat tissue distribution and function, assessing the risk of obesity-related conditions such as metabolic syndrome (MetS) and stroke, which are strongly connected to OSA. The relationship between CMI with OSA and OSA combined with MetS (OMS) remains unclear. This study aims to evaluate the screening value of CMI for OSA and OMS, compared to the lipid accumulation product (LAP). Methods: A total of 280 participants who underwent polysomnography were finally included, with the measurements of metabolic-related laboratory test results such as total cholesterol and triglyceride. Receiver operating curve (ROC) analysis and calculation of the area under the curve (AUC) were conducted to assess the screening potential of CMI, LAP, and the logistic regression models established based on them for OSA and OMS. The Youden index, sensitivity, and specificity were used to determine the optimal cutoff points. Results: ROC curve analysis revealed that the AUCs for CMI in screening OSA and OMS were 0.808 and 0.797, and the optimal cutoff values were 0.71 (sensitivity 0.797, specificity 0.776) and 0.89 (sensitivity 0.830, specificity 0.662), respectively, showing higher Youden index than LAP. The AUCs of screening models based on CMI for OSA and OMS were 0.887 and 0.824, respectively. Conclusion: CMI and LAP can effectively screen for OSA and OMS, while CMI has more practical cutoff values for identifying the diseased states. Screening models based on CMI demonstrate a high discriminatory ability for OSA and OMS, which needs verification in a large-scale population.

Effects of hypobaria, hyperoxia, and nitrogen form on the growth and nutritional quality of lettuce.

The objectives of this research were to investigate the impact of hypobaria, hyperoxia, and nitrogen form on the growth and nutritional quality of plants. Pre-culture 20-day-old lettuce (Lactuca sativa L. var. Rome) seedlings grew for 25 days under three levels of total atmospheric pressure (101, 54, and 30 kPa), two levels of oxygen partial pressure (21 and 28 kPa), and two forms of nitrogen (NO3N and NH4N). The ratios of NO3N to NH4N included 3: 1, 4: 0, 2: 2, and 0: 4. The nitrogen quantity included two levels, i.e. N1, 0.1 g N kg-1 dry matrix and N2, 0.2 g N kg-1 dry matrix. The growth status of lettuce plants in different treatments differentiated markedly. Regardless of the nitrogen factor, the growth status of lettuce plants treated with total atmospheric pressure/oxygen partial pressure at 54/21 was equivalent to the treatment of 101/21. Under the hypobaric condition (54 kPa), compared with 21 kPa oxygen partial pressure, hyperoxia (28 kPa) significantly inhibited the growth of lettuce plants and the biomass (fresh weight) decreased by 60.9%-69.9% compared with that under 101/21 treatment. At the N1 level, the sequence of the biomass of lettuce plants supplied with different ratios of NO3N to NH4N was 3: 1 > 4: 0 > 2: 2 > 0: 4, and there were higher concentrations of chlorophyll and carotenoid of lettuce plants supplied with the higher ratio of NO3 to NH4. At the N2 level, the effects of different ratios of NO3N to NH4N on lettuce plants were similar to those at the N1 level. The high nitrogen (N2) promoted the growth of lettuce plants such as 54/21/N2 treatments. Both form and nitrogen level did not affect the stress resistance of lettuce plants. Hypobaria (54 kPa) increased the contents of N, P, and K and hyperoxia (28 kPa) decreased the content of organic carbon in lettuce plants. The high nitrogen (N2) improved the content of total N and the N uptake. The ratios of NO3N to NH4N were 4: 0 and 3: 1, lettuce could absorb and utilize N effectively. This study demonstrated that hyperoxia (28 kPa) inhibited the growth of lettuce plants under the hypobaric condition (54 kPa), and high level of nitrogen (0.2 g N kg-1 dry matrix) and NO3N: NH4N at 3: 1 markedly enhanced the growth, the contents of mineral elements and the nutritional quality of lettuce plants.

PMMA-Based Composite Gel Polymer Electrolyte with Plastic Crystal Adopted for High-Performance Solid ECDs.

A PMMA-based gel polymer electrolyte (GPE) modified by a plastic crystal succinonitrile (SN) was synthesized using a facile solvent-casting method. The effects of SN additives upon lithium-ion dissociation and ionic conductivity were investigated primarily using Fourier transform infrared spectroscopy and electrochemical impedance spectroscopy, accompanied by other structural characterization methods. The results show that SN is distributed uniformly in the PMMA matrix with a high content and produces vast dipoles that benefit the dissociation of lithium salt. Hence, the SN-modified GPE (SN-GPE) achieves an excellent ionic conductivity of 2.02 mS·cm-1 and good mechanical properties. The quasi-solid-state ECD fabricated using the SN-GPE exhibits stable cyclability and excellent electrochromic performance, in which the bleaching/coloration response time is 10 s/30 s. These results add significant insight into understanding the inter- and intra-molecular interaction in SN-GPEs and provide a type of practicable high-performance GPE material for solid electrochromic devices.

Establishment and Application Evaluation of an Improved Obstructive Sleep Apnea Screening Questionnaire for Chinese Community: The CNCQ-OSA.

Objective: Obstructive sleep apnea (OSA) is a common sleep-disordered breathing disease. We aimed to establish an improved screening questionnaire without physical examinations for OSA named the CNCQ-OSA (Chinese community questionnaire for OSA). Methods: A total of 2585 participants who visited sleep medicine center and underwent overnight polysomnography were grouped into two independent cohorts: derivation (n = 2180) and validation (n = 405). The CNCQ-OSA was designed according to the baseline of patients in derivation cohort. We comprehensively analyzed the data to evaluate the predictive value of the CNCQ-OSA, compared to the GOAL questionnaire, STOP-Bang questionnaire (SBQ) and NoSAS questionnaire. Results: The CNCQ-OSA included seven variables: loud snoring, BMI ≥ 25 kg/m2, male gender, apnea, sleepiness, hypertension and age ≥30, with a total score ranging from 7 to 16.7 points (≥13.5 points indicating high risk of OSA, ≥14.5 points indicating extremely high risk). In the derivation and validation cohorts, the areas under the curve of the CNCQ-OSA were 0.761 and 0.767, respectively. In the validation cohort, the sensitivity and specificity of a CNCQ-OSA score ≥13.5 points for the apnea-hypopnea index (AHI) ≥5/h were 0.821 and 0.559, respectively (Youden index, 0.380), and the score ≥14.5 points were 0.494 and 0.887, respectively (Youden index, 0.375). The CNCQ-OSA had a better predictive value for AHI ≥ 5/h, AHI > 15/h and AHI > 30/h, with the highest Youden index, compared to the other questionnaires. Conclusion: The CNCQ-OSA can effectively identify the risk of OSA, which is appropriate for self-screening at home without physical examinations.

The relationship between obstructive sleep apnea and asthma severity and vice versa: a systematic review and meta-analysis.

BACKGROUND: There is a great association between the prevalence of obstructive sleep apnea (OSA) and asthma. Nonetheless, whether OSA impacts lung function, symptoms, and control in asthma and whether asthma increases the respiratory events in OSA are unknown. This meta-analysis aimed to examine the relationship between obstructive sleep apnea and asthma severity and vice versa. METHODS: We carried out a systematic search of PubMed, EMBASE, and Scopus from inception to September 2022. Primary outcomes were lung function, parameters of polysomnography, the risk of OSA in more severe or difficult-to-control asthmatic patients, and the risk of asthma in patients with more severe OSA. Heterogeneity was examined with the Q test and I2 statistics. We also performed subgroup analysis, Meta-regression, and Egger's test for bias analysis. RESULTS: 34 studies with 27,912 subjects were totally included. The results showed that the comorbidity of OSA aggravated lung function in asthmatic patients with a consequent decreased forced expiratory volume in one second %predicted (%FEV1) and the effect was particularly evident in children. %FEV1 tended to decrease in adult asthma patients complicated with OSA, but did not reach statistical significance. Interestingly, the risk of asthma seemed to be slightly lower in patients with more severe OSA (OR = 0.87, 95%CI 0.763-0.998). Asthma had no significant effect on polysomnography, but increased daytime sleepiness assessed by the Epworth Sleepiness Scale in OSA patients (WMD = 0.60, 95%CI 0.16-1.04). More severe asthma or difficult-to-control asthma was independently associated with OSA (odds ratio (OR) = 4.36, 95%CI 2.49-7.64). CONCLUSION: OSA was associated with more severe or difficult-to-control asthma with decreased %FEV1 in children. The effect of OSA on lung function in adult patients should be further confirmed. Asthma increased daytime sleepiness in OSA patients. More studies are warranted to investigate the effect of asthma on OSA severity and the impact of different OSA severity on the prevalence of asthma. It is strongly recommended that people with moderate-to-severe or difficult-to-control asthma screen for OSA and get the appropriate treatment.

Study on primary physicochemical characteristics and nutrient adsorption of four plant cultivation substrates.

The primary physicochemical characteristics and the nutrient adsorption of different substrates were carried out, to select suitable cultivation substrates for plant cultivation in space. Four types of plant cultivation substrates (Profile substrate (P), black ceramsite (B), white ceramsite (W), and vermiculite (V)) were used to test and compare the primary physicochemical characteristics, such as micropore, bulk density, total porosity, specific surface area and available nutrient content, as well as the nutrients adsorption for NH4+, NO3-, PO43- and K+ with seven concentration gradients respectively. Substrate P contained more micropores, with higher parameter values of total porosity, cation exchange capacity, electrical conductivity, and specific surface area, moderate bulk density and pH, and more mineral nutrients such as potassium, magnesium, and sulfur; substrate B was porous, with smaller parameter values of total porosity, cation exchange capacity and specific surface area, minimum electrical conductivity, moderate bulk density, alkaline and smaller content of mineral elements (excepting for calcium); substrate W had smaller micropore size, the highest value of bulk density and contents of NO3- and PO43-. Other physicochemical parameters were equivalent to those of substrate B; substrate V was flaky, with the smallest values of bulk density, and the highest values of total porosity and cation exchange capacity. The values of electrical conductivity and specific surface area were smaller than those of substrate P. It contained more mineral nutrients of calcium and sulfur. Substrate V had the highest adsorption capacity for NH4+, NO3-, PO43- and K+, followed by substrate P, while substrate B and substrate W had relatively weak adsorption capacity. The adsorption capacity of four substrates for cations (NH4+ and K+) was significantly higher than that for anions (NO3- and PO43-). The orders of average adsorption amount for NH4+, NO3-, PO43- and K+ by four substrates were respectively: V > P > B > W, P > V > W > B, V > P > B > W and V > P > W > B. In comparison, substrate P and substrate V had better physicochemical characteristics, and stronger adsorption capacity for NH4+, NO3-, PO43-, and K+.

The main driver of soil organic carbon differs greatly between topsoil and subsoil in a grazing steppe.

Soil organic carbon (SOC) dynamics is regulated by a complex interplay of factors such as climate and potential anthropogenic activities. Livestocks play a key role in regulating the C cycle in grasslands. However, the interrelationship between SOC and these drivers remains unclear at different soil layers, and their potential relationships network have rarely been quantitatively assessed. Here, we completed a six-year manipulation experiment of grazing exclusion (no grazing: NG) and increasing grazing intensity (light grazing: LG, medium grazing: MG, heavy grazing: HG). We tested light fraction organic carbon (LFOC) and heavy fraction organic carbon (HFOC) in 12 plots along grazing intensity in three soil layers (topsoil: 0-10 cm, mid-soil: 10-30 cm, subsoil: 30-50 cm) to assess the drivers of SOC. Grazing significantly reduced SOC of the soil profile, but with significant depth and time dependencies. (1) SOC and SOC stability of the topsoil is primarily regulated by grazing duration (years). Specifically, grazing duration and grazing intensity increased the SOC lability of topsoil due to an increase in LFOC. (2) Grazing intensity was the major factor affecting the mid-soil SOC dynamics, among which MG had significantly lower SOC than did NG. (3) Subsoil organic carbon dynamics were mainly regulated by climatic factors. The increase in mean annual temperature (MAT) may have promoted the turnover of LFOC to HFOC in the subsoil. Synthesis and applications. When evaluating the impacts of grazing on soil organic fraction, we need to consider the differences in sampling depth and the duration of grazing years. Our results highlight that the key factors influencing SOC dynamics differ among soil layers. Climatic and grazing factors have different roles in determining SOC in each soil layer.

Design and establishment of a large-scale controlled ecological life-support system integrated experimental platform.

A Controlled Ecological Life-Support System (CELSS) can meet the demands of food, oxygen, and water for human, as well as providing psychological benefits during deep space exploration by the continuous materials regeneration. Many key techniques of the platform are needed to explore before applying to the extraterrestrial planets. In this study, a large-scale CELSS integrated experimental platform was designed and constructed to meet the basic life-support material demands of six crew members (max). The platform was composed of four kinds of cabins including Crew Cabin (CC), Plant Cabin (PC), Life-Support Cabin (LSC), Resource Recycling Cabin (RRC) and affiliated facilities. Eight cabins were involved in the platform, i.e., CCs I and II, PCs I, II, III and IV, LSC, and RRC. The platform involved 15 subsystems and covered a plant culture area of 206.6 m2 (a max extensible area of 260 m2) and a total volume of 1340 m3. The joint debuggings and the 4-subject 180-day CELSS integration experiment were carried out successfully. The material closures were 55% (on average) for food (70.8% in highly efficient production period), 100% for atmospheric regeneration, 100% for water regeneration, and 87.7% for recycled solid waste in the 4-subject 180-day integration experiment. It verified that the indicators of the platform meet the technical requirements and realize food regeneration, air regeneration and water regeneration through the integration of physico-chemical technique and biological technique for the long-term survivals of six crew members in the closed cabins.

Operation overview of a biological waste treatment system during the 4-crew 180-day integrated experiment in the controlled ecological life support system (CELSS).

Waste management and treatment is vital to health care and material circulation, especially in the Controlled Ecological Life Support System (CELSS) with finite resources for long-duration manned space missions. A closed ecological-cycle integrated 4-crew 180-day experiment platform was established to investigate the key technologies such as effective cultivation of higher plant, water treatment and recycling, waste management and treatment. In this study, generated waste during the integrated experiment was classified as renewable and non-renewable waste. The renewable waste including all crew feces and part of inedible plant biomass were treated in a biological system where the aerobic composting technology was utilized. The performance in relation to degradation effect, phytotoxicity and nutrient evaluation was examined during the continuous 180 days. The long-term operation results displayed that 96.26 kg feces and 74.4 kg wheat straw were treated, and 90.6 kg compost product was discharged in nine batches. The microbial community variation was analyzed and Firmicutes, Actinobacteria and Proteobacteria enriched in the compost. The phytotoxicity of compost was examined by seed germination index (GI) and GI of Chinese cabbage ranged from 88% to 132% for all batches. Compared to grown in vermiculite only, the lettuce yield increased 19% when grown in a mixture of vermiculite and processed compost. The summary of this work will be helpful to facilitate future applications of aerobic composting technology as the bio-based waste treatment technology in CELSS.

The effect of non-benzodiazepine sedative hypnotics on CPAP adherence in patients with OSA: a systematic review and meta-analysis.

STUDY OBJECTIVES: This meta-analysis aimed to explore the effect of non-benzodiazepine sedative hypnotics (NBSH) on continuous positive airway pressure (CPAP) adherence in patients with obstructive sleep apnea (OSA). METHODS: We conducted a systematic search through PubMed, Medline, the Cochrane Library, EMBASE, Scopus and ClinicalTrials (all searched from inception to August 15, 2020). Publications were limited to articles, clinical conferences and letters, including randomized controlled trials and retrospective studies. We used a random-effects model to calculate the odds ratio (OR) and mean difference (MD) with corresponding confidence interval (CI). Subgroup analyses were conducted to analyze the sources of heterogeneity. RESULTS: Eight studies fulfilled the inclusion and exclusion criteria for patients newly diagnosed with obstructive sleep apnea. Overall, the use of NBSH was associated with increased use of CPAP per night (MD = 0.62 h; 95% CI = 0.26-0.98) and use for more nights (MD = 12.08%; 95% CI = 5.27-18.88). When a study seriously affecting heterogeneity was removed, more patients adhered well with CPAP use (pooled OR = 2.48; 95% CI = 1.75-3.52) with good adherence defined as CPAP use for >4 h/night on >70% of nights. Among prescribed NBSHs, eszopiclone showed the most significant effect on CPAP adherence. CONCLUSION: CPAP adherence may increase in OSA patients treated with non-benzodiazepine sedative hypnotics especially eszopiclone. The effect of zolpidem and zaleplon on CPAP adherence requires further investigation by larger scale, randomized, controlled trials.

Wheat Cultivation and Nutrient Control for the 180-day CELSS Integrated Experiment.

This research aimed to select the well-adapted wheat cultivar and to explore an optimum nutrient control pattern for wheat cultivation in the 180-day integrated experiment of controlled ecological life support system (CELSS). In the experiment, six wheat cultivars from different areas of China were preselected and cultivated in four separate recirculating hydroponic systems (HySy), nutrients in which could be controlled and recycled according the values of pH, electrical conductivity (EC) and dissolved oxygen (DO). Wheat covered an area of 111.3 m2 and had been planted in 17 batches with a 15-day time interval to realize stable regeneration of oxygen, water and food during the 180-day duration in the closed cabin. The results indicated that different cultivars displayed different adaptabilities to the controlled environment. Wt04 had a stronger adaptability with the highest yield (12.82 g DM m-2 d-1) and edible radiation use efficiency (RUE) (0.28 g DM mol-1) whereas Wt06 adapted this environment poorly because of its excessive vegetative growth. For the morphological characters, wheat plants tended to dwarf in the CELSS environment compared with the field. An innovative controlling pattern was established for nutrient supplement. Through the real-time monitoring of pH, EC and DO of the nutrient solution and the periodical detection of the contents of nutrient elements, the nutrient solution could be controlled and recycled continuously without being renewed under a suitable state for wheat plants growth during the 180-day integrated experiment.

Effects of LED spectra on growth, gas exchange, antioxidant activity and nutritional quality of vegetable species.

This research aimed to investigate the effects of three LED spectra on growth, gas exchange, antioxidant activity and nutritional quality of three vegetable species. The compressible vegetable facilities (CVF) were developed and three kinds of typical LED lights (spectra) were set, including white LED light (W), red-blue-green LED light (RBG), and red-blue-white LED light (RBW). Three vegetable species, i.e. lettuce (Lactuca sativa L. cv. Rome), cherry radish (Raphanus sativas L. cv. Hongxin) and cherry tomato (Lycopersicon esculentum M. cv. Mosite), were chosen and grown (matrix culture) in the three LED lights for 40, 40 and 100 days, respectively. The results indicated that the vegetable plants grew well and were compact in the RBG and RBW treatments. There was the highest biomass or fruit (tomato) in the RBG treatment and the least one in the W treatment for three vegetable species. There were no significant differences in harvest index, ratio of shoot to root, and water content among three treatments. The production efficiency values of 9.0-9.7, 9.9-13.5 and 11.8-12.5 g DW d-1 m-2 for lettuce, radish and tomato plants in the RBG and the RBW treatments were higher than those in the W treatment. The photosynthetic and transpiration rates of three vegetable species in the RBG treatment were the highest among three treatments and the W treatment had the least one. There were significant effects of three spectra on antioxidant activities of three vegetable species. Higher PPFD percentages of blue in the RBG light and the RBW light increased the antioxidant activities of all vegetable plants compared the W light. But it had no significant difference between the RBG light and the RBW. The organic components including soluble sugar (SS) and protein (Prt) of lettuce and radish plants were affected significantly by three spectra, but not for tomato plants. The contents of Mg and Zn of radish plants in the RBG treatment were higher than those in other treatments. There were significant positive effects of RBW treatment on the contents of N and Mg of tomato plants. The different spectra did not affect the contents of N-NO3 and Cu of vegetable plants. This study demonstrated that the RBG light (spectrum) significantly enhanced the growth, gas exchange, antioxidant activity of the lettuce, radish, and tomato cultivars used in this study, and there are significant effects of different LED spectra on the nutritional quality (including organic components and several mineral elements) of the different species.

YIPF2 promotes chemotherapeutic agent-mediated apoptosis via enhancing TNFRSF10B recycling to plasma membrane in non-small cell lung cancer cells.

Non-small cell lung cancer (NSCLC) is the most common histological type of lung cancer, and the identification of the apoptotic process of NSCLC is vital for its treatment. Usually, both the expression level and the cell surface level of TNFRSF10B (TNF Receptor superfamily member 10B) will increase after treatment with some chemotherapeutic agents, which plays a critical role in the apoptosis induction. However, the exact molecular mechanism underlying TNFRSF10B regulation remains largely elusive. Here, we found that TNFRSF10B, along with a vesicular trafficking regulator protein, YIPF2, were upregulated after treatment with pemetrexed (PEM) in NSCLC cells. Besides, YIPF2 increased the surface level of TNFRF10B, while YIPF2 knockdown inhibited the upregulation of TNFRSF10B and its recycling to plasma membrane. In addition, RAB8 decreased the cell surface TNFRSF10B by promoting its removing from plasma membrane to cytoplasm. Furthermore, we found that YIPF2, RAB8 and TNFRSF10B proteins interacted physically with each other. YIPF2 could further inhibit the physical interaction between TNFRSF10B and RAB8, thereby suppressing the removing of TNFRSF10B from plasma membrane to cytoplasm mediated by RAB8 and maintaining its high level on cell surface. Finally, using bioinformatics database, the YIPF2-TNFRSF10B axis was confirmed to be associated with the malignant progression of lung cancer. Taken together, we show that YIPF2 promotes chemotherapeutic agent-mediated apoptosis via enhancing TNFRSF10B recycling to plasma membrane in NSCLC cells. These findings may be beneficial for the development of potential prognostic markers of NSCLC and may provide effective treatment strategy.

Effects and relationships of grazing intensity on multiple ecosystem services in the Inner Mongolian steppe.

Grassland ecosystems are one of the most important terrestrial ecosystems in the world, producing essential both goods and ecosystem services (ES) for human beings. The Inner Mongolian steppe is a major grassland ecosystem in Northern China, covering 13.5% of the northern Chinese grassland area, and playing important ecological roles for the adjacent region of the capital Beijing-Tianjin-Hebei. Quantification of grassland ES under the different utilization patterns is vital for the maintenance of multiple ES and mitigation against ES loss in this region. We made a manipulative experiment with four grazing intensities (grazing exclusion, GE; light grazing intensity, LG; medium grazing intensity, MG; heavy grazing intensity, HG). We then quantified the intensities of eight different grassland ES (1. herbage intake, HT; 2. biodiversity conservation, BI; 3. soil nutrient retention, SN; 4 soil carbon stocks SC; 5. soil erosion prevention, SEP; 6. soil water storage, SWC; 7. potential nutrient recycling, PNC; 8. carbon sequestration from atmosphere. CS) and total ES via a series of field measurements. Pearson coefficients and trade-offs index were used to access the above ES relationships and degree of trade-offs between ES. Grazing intensities significantly (p < 0.05) affected the grassland intensities of 'regulating', 'culture' and 'provisioning' services, but the 'supporting' services. We found three types of relationships (trade-offs, synergy or neutral) have been found in this study. Trade-offs occurred between 'provisioning' and 'regulating' services. Although GE management presented significantly higher intensity of total ES (0.64) than LG (0.52), LG management significantly weakened the trade-offs between 'provisioning' and 'regulating' services (Trade-offs index 0.22) in comparison with GE (Trade-offs index 11.02). Our study suggests, therefore, that LG is the most suitable grassland utilization practice in the Inner Mongolian steppe.

High-Efficiency and Wide-Angle Versatile Polarization Controller Based on Metagratings.

Metamaterials with their customized properties enable us to efficiently manipulate the polarization states of electromagnetic waves with flexible approaches, which is of great significance in various realms. However, most current metamaterial-based polarization controllers can only realize single function, which has extremely hindered the expansion of their applications. Here, we experimentally demonstrate highly efficient and multifunctional polarization conversion effects using metagrating by integrating single-structure metallic meta-atoms into the dielectric gratings. Benefiting from the combined advantages of the gratings and the metamaterials, the considered metagrating can operate in transmission and reflection modes simultaneously, acting as a high-performance and wide-angle quarter-wave or half-wave plate with distinct functions in different frequency bands. This metagrating structure is scalable to other frequency ranges and may provide opportunities to design compact multifunctional optical polarization control devices.

Water management in a controlled ecological life support system during a 4-person-180-day integrated experiment: Configuration and performance.

Water management subsystem (WMS) is a major component of the controlled ecological life support system (CELSS). For guaranteeing the water requirement of crop growth and crewmember's daily life, a WMS was established in a 4 person 180-day integrated experiment (carried out in Shenzhen, China, 2016) to maintain a closed cycle with a total water amount of ~23 m3. The design and operation of the WMS was summarized as follows: (1) Collection and allocation of condensate water. About 917 L/d condensate water (>98% was from plants' evapotranspiration) was collected, and ~866 L/d of which was reused as plant nutrient solution after ultraviolet (UV) disinfection, and 50.6 L/d was used as the raw water for the domestic water supply module (DWS). (2) Domestic water supply. The condensate water from the plant cabin was purified through the DWS, a modified membrane bioreactor (MBR) system, and then provided hygiene and potable water to 4 crewmembers with different water quality standards. (3) Wastewater recovery. 51.4 L/d wastewater from urination and personal hygiene were treated together via a biological wastewater treatment process to complete the conversion of nitrogen and organic matters, and then recycled to plant nutrient solution. (4) Nutrient solution recycling. In the overall water cycle process, the plant nutrient solution was continuously self-circulated and the water quality of which was maintained at a relatively stable level with total organic carbon of 20-30 mg/L and NH4+-N < 1.0 mg/L. The 180-day continuous operation demonstrated that a 100% water closure was achieved. Based on the results of this study, an upgraded water cycle system for larger-scale and longer-term CELSS has been proposed.

Preparation of Silver Nanowires with High Aspect Ratio and Influence of Reaction Conditions on the Morphology Size.

Silver nanowires with high yield, uniform size and high aspect ratio were successfully synthesized by a simple and effective polyol method under low temperature and quiescent conditions, adopting CuCl2·2H2O as the nucleation control agent for the first time. The synthesized silver nanowires were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV-Vis diffuse reflectance spectroscopy (DRS). The results indicate that the silver nanowires were composed of face-centered cubic structure of pure metallic silver with high crystallinity. And the silver nanowires have an average length of 80~100 µm and an average diameter of 40~80 nm. Thus, the aspect ratio of the nanowires was greater than 1000. In addition, the influence on the morphology and structure of the silver nanowires were investigated for reaction temperature, mole ratio of PVP:AgNO3, molecular weight of PVP and mole ratio of control agent CuCl2 · 2H2O:AgNO3. Finally, the optimum reaction condition were obtained for the preparation of the silver nanowires with high aspect ratio.

[Progress of biological air filter (BAF) development in manned spacecraft cabin].

The contaminants originating from human metabolism, material off-gassing and waste processing, may influence human health and the growth and development of higher plants when they accumulate at some degree in the spacecraft cabin. So the contaminants concentrations must be controlled below the spacecraft maximum allowable concentration (SMAC). For the long manned space missions and planetary habitation, biological technique is available for the removal of the contaminants. The biological air filter, BAF, is a system that degrades the contaminants into carbon dioxide, water and salts. It holds many advantages such as small weight and volume, low power consumption, easy maintenance and good working performance under the condition of microgravity. Its wide application will be seen in the space field in near future.

[Development of a prototype of space vegetable-cultivating facility for ground-based experiments].

OBJECTIVE: To develop a ground-based experimental prototype of space vegetable-cultivating facility (GEPSVF), so as to solve the main key techniques related to higher plant cultivation in space environmental conditions, and to further lay a foundation for future development and application of the prototype of space vegetable-growing facility. METHOD: Based on detailed demonstration and design of technique plan, the blueprint design and machining of components, whole facility installment, debugging, trial operations and verification experiments were done. RESULT: The parameters in the growing chamber such as temperature, relative humidity, wind velocity, total pressure, O2 partial pressure, CO2 partial pressure and water content of the growing media were totally and effectively controlled; the light source was electronic fluorescent lamp; the average vegetable-producing output reached 60 g (fresh weight) d-1. CONCLUSION: The prototype could operate stably; its actual performance indexes achieved the expected ones basically; some of its operating principles can adapt to space microgravity condition. Therefore, the prototype is a good beginning for future development of space vegetable-producing facilities.