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Shrub cover in alpine meadows around the world has experienced significant changes during the past 20 yr. An increase in shrub cover has often been associated with large influences in ecosystem functions. The objectives of the present study were to investigate the impact of shrub cover on herbaceous forage quality and yak grazing efficiency on the Qinghai-Tibetan Plateau, China. Forty-eight yak steers were randomly assigned to four grazing pastures with different shrub cover rates (control, low, middle, and high). The whole grazing period was categorized as vegetative stage (June to July), bloom stage (August to October), and senescent stage (November to December). Herbaceous forage chemical composition and body weight of yaks were measured, and serum and rumen samples were analyzed. Although shrub cover had no effect on herbaceous forage chemical composition and serum biochemical parameters of yaks, total herbaceous forage production in pastures and crude protein intake of yaks decreased with increasing shrub cover. Such changes decreased average daily gain of yaks. As expected, increasing the herbaceous forage maturation significantly decreased crude protein content while increased dry matter, neutral detergent fiber and acid detergent fiber contents, consequently, reduced herbaceous forage crude protein and organic matter intakes and average daily gain of yaks. The rumen of yaks has higher ammonia nitrogen and total volatile fatty acid concentrations and butyrate proportion in the bloom stage of forage compared with those of the senescent stage. The results indicate that shrub cover on the Qinghai-Tibetan Plateau needs a certain level of control for the sustainable grazing yak production, although it has little negative effect on blood health and rumen fermentation. Additionally, it is vital to select the optimum time to market livestock or supplement feed with yaks during the cold season on the Qinghai-Tibetan Plateau.

Enveloped viruses can cause devastating zoonotic diseases and are the most likely to cause global pandemics. We identified a new class of small-molecule sulfur-containing antiviral compounds (XM series) that broadly inhibit enveloped viruses. The antivirals’ mechanism of action was explored via various multidisciplinary approaches, concluding that the XM antivirals alter membrane lipid chemical compositions, increase membrane order deep within the hydrophobic region of the bilayer, and increase membrane phase transition temperatures. Such effects cause inhibition of membrane fusion and viral entry, while leaving the viral glycoproteins and genomes largely unaffected. Consequently, we tested whether these features would lead to effective whole inactivated enveloped virus vaccines. As a proof-of-principle, we generated an inactivated influenza virus (IIV) vaccine using compound XM-01 (XM-01-IIV). We compared this new vaccine to traditional paraformaldehyde-inactivated, to control compound-inactivated, and to live virus vaccines, using a mouse model of disease. Excitingly, compared to a traditional IIV vaccine, XM-01-IIV vaccination improved neutralizing antibody responses against both hemagglutinin and neuraminidase, and decreased mouse morbidity and mortality following influenza virus challenge. Therefore, this study uncovers a novel class of broadly acting antivirals that enhances influenza virus vaccine development and offers great potential for broadly generating future highly-potent inactivated enveloped virus vaccines.

This study investigated the influences of herbivore grazing intensity and grazing season on decomposition and nutrient release of dung and litter, which aimed to improve our understandings of grazing affecting nutrient cycling in alpine meadows on the Qinghai-Tibetan Platean. A factorial design experiment comprising 3 grazing intensities (non-grazing, moderate grazing, and heavy grazing) and 2 grazing seasons (summer and winter), was applied to quantify the decomposition and chemistry of dung and litter in an alpine pasture using the litterbag technique. Litterbags were retrieved for analysis of mass loss and nutrient release with 180, 360, 540, and 720 days after placement. Grazing activity accelerated the decomposition of dung and litter and increased nutrient release from dung and litter by increasing soil temperature compared with non-grazing pastures, whereas grazing season had no effect on decomposition. The decomposition time was shorter for dung than that for litter. Herbivores grazing benefited dung and litter decomposition and nutrient cycling directly by increasing soil temperature, which is likely to promote soil microbial activity due to low temperatures in alpine meadows, and indirectly through herbage ingestion and dung deposition which increase the organic debris concentration used for microorganisms growth and reproduction. This study provides insights into the mechanisms of grazing regulating nutrient cycling in alpine ecosystems.

NOx emission from the ternary eutectic molten salt (7 wt%NaNO3-40 wt%NaNO2-53 wt%KNO3, HITEC) has been investigated in thermal energy storage (TES) processes. The effect of different metal and exposure time on NOx emission is evaluated, including Incoloy 625 and Hastelloy C276® of nickel-based alloys, and AISI 310S (310S) and AISI 321 (321) of stainless steels. The mechanism of NOx emissions is analyzed by using thermodynamic calculation, scanning electron microscopy (SEM), energy dispersive X-Ray (EDX), X-ray diffractometer (XRD) and atomic absorption spectrophotometer (AAS). The experimental results indicate that HITEC can release less than 40 mg/m3 of NOx when exposing to In625 or HasC276 alloys below 500 °C, and more than 350 mg/m3 of NOx for 310S and 321 at 500 °C. It is found that oxide film is formed on metals surface for long exposure time in HITEC resulting in the decrease of NOx emission. The calculated Gibbs free energy change reveals that above 500 °C, Cr2O3 protective films on the metals are reduced, which contributes to rapid increase of NO2 and NO emissions. In625 or HasC276 alloys is recommend to be used in pipe line/container, and the NOx emissions of HITEC based TES system can be effectively decreased especially for long-term energy storage.

Supplementation of livestock feed is a common strategy for improving animal production in pasture-based systems worldwide. On the Qinghai-Tibet Plateau of China, however, the grassland ecosystem is fragile and therefore sensitive to disruption by external forces. We therefore investigated the effects of supplementing yaks feed with oats hay on animal production, forage biomass, and carbon return in litter and dung as well as the effects on soil organic carbon stock. Two grazing systems—native grazing, or grazing with hay supplementation—were established in 2010. For the native grazing system, yaks were rotationally grazed in two paddocks (3.3 yaks/ha) with each 15 days during the warm season (July through October) and 20 days during the cold season (November through June). The hay supplementation system was the same as the native system except that each yak also received oats hay (1.5 kg/day, dry matter basis) during the cold season. For each system, yak growth, forage biomass of the pasture, carbon return from litter and dung to soil, and soil organic carbon stock were measured from 2010 to 2014. The yaks supplemented with oats hay had greater growth performance compared with non-supplemented animals, thereby providing economic benefits for herdsmen. With respect to carbon cycling, supplementation increased carbon return in litter and dung and consequently reduced the soil carbon stock loss. The results indicate that supplementation with oats hay positively impacted forage production and carbon cycling in alpine meadows and thus may help remediate degraded soils and improve grassland utilization on the Qinghai-Tibet Plateau.

CONTEXT A large number of field trials assessing supplementary feeding have been conducted on the Qinghai-Tibet Plateau but its influence on nitrogen (N) cycling particularly N addition to soil through litter or dung deposition and the effect on soil N levels remain poorly understood. OBJECTIVE Here we investigated the effects of oat hay supplementation on forage biomass, N return from litter and dung to soil and soil N levels by comparing supplemented and non-supplemented systems. METHODS The non-supplemented system of yak was based on typical native grazing practices and was established in 2010. Grazing in supplementary feeding system was identical but each yak received oat hay (0.5, 1.0 or 1.5 kg/day, dry matter basis) during the cold season. For each system, forage biomass, N return from litter and dung to soil, and soil N levels were measured from 2010 to 2014. RESULTS AND CONCLUSIONS The results showed that supplementation systems increased 12.8% of forage biomass and enhanced N return from litter and dung to soil by 8.0% and 6.2%, respectively, compared with native grazing systems, but did not change soil N stock. Forage biomass (slope, 0.596 to 1.769) and return of N from litter to the soil (slope, 0.359 to 0.677) increased significantly as the trial progressed in supplementation systems. Increased forage biomass resulted in increased N uptake offsetting the supplement-induced soil N input resulting in minimal change in soil N. SIGNIFICANCE The conceptual framework firstly quantized the effect size of supplementary regime on N cycling of grazing systems and soil N levels in alpine meadows. It can be used for an essential model and extended to other agroecosystem that show the influence of external disturbances on nutrient cycling.

This work aimed at investigating the mechanism of NOx emissions from binary molten nitrate (BMN) salts (an eutectic salt mixture with the component of 60%NaNO3-40%KNO3) in its thermal energy storage (TES) process while contacting several kinds of nickel base alloy and determining the optimized temperature range of BMN salts in these metal loops. According to the national environmental protection standard of PR China, HJ479-2009, the concentrations of NO/NO2 net emissions in tail gases from the heated molten salts while contacting with Inconel 625 (In625), Hastelloy C276 (HasC 276), Hastelloy X (Has X) and Inconel 600 (In600) were measured in TES process, which were deducted the influence of platinum boat while contacting with the molten nitrates. Besides, the In625 and HasC 276 were chosen to test with the same method at 500 °C under the condition that they were corroded at 500 °C after a period of time, SEM/EDS and XRD techniques were utilized to study the surface morphology and corrosion products after a maximum immersion time of 600 h. Furthermore, the chemical thermodynamic calculations of related reactions that between Cr, Ni, Mo, W and nitrate salts were carried out to explain the source of NO/NO2. The test results show that BMN salts contained in pipes or tanks made of nickel base alloy under air atmosphere in certain conditions can release NOx in its usage temperature range, and the concentrations of NOx emissions increase with the rise of the temperature. Below 500 °C, the concentrations of NOx net emissions that BMN salts contacting with these four kinds of nickel base alloys were under 200 mg/m3, which is in accordance with the emission limit of thermal power plant in China and the emission limit of second directive of EU in coal-fired power plant. Besides, the concentrations of NOx emissions that BMN salts contacting with corrode materials would decrease to some extent. After a period of corrosion, the formed oxide film on metal surface was very thin but dense. Therefore, the BMN salts were advisable to utilize under 500 °C at the initial stage, and it can be used at higher temperature after the stable oxide film formed in the metal surface.

To research the different emissions of NOx when HITEC (an eutectic mixture of ternary molten nitrates with the component of 7wt.%NaNO3-53wt.%KNO3-40wt.%NaNO2) contacts with metals during the thermal energy storage (TES) process, this paper studies the accumulative absorption concentrations of NOx in tail gases generated from the molten salts exposure to 45# carbon steel (1045, ASTM), stainless steels(321, 310S), and nickel-based alloys(In625, Has C276) respectively under different temperatures, according to the national environmental protection standard of PR China, HJ479-2009. The results indicated that HITEC could release NOx when it contacted with those metals within the range from 300°C to 600°C. The emissions of NOx slowly increased with the increasing temperature under 450°C, but they were all less than 200mg/m3. The NOx emissions had a sharp rise as HITEC contacting with 321 and 310S above 450°C, and their quantities were 1300 mg/m3 and 770 mg/m3 at 550°C respectively. When HITEC contacted with Has C276 and In625 above 500°C, the NOx emissions had a greatly increase, and their quantities were 340 mg/m3 and 265 mg/m3 at 550°C respectively. As for 45# carbon steel, the emissions were higher than 200 mg/m3 at 585°C.The chemical thermodynamic computation revealed that NOx were generated by various redox reactions between nitrate or nitrite and Fe, Ni, Cr, Mo, W below 450°C, but the emissions were not large for oxide films covered on metal surface could restrain the reactions. The formed Cr2O3, on surface of stainless steel and nickel based alloy, were further oxidized with NaNO3 and KNO3 above 500°C, leading to the oxide films to be damaged, and then NO2 and NO to be released. There was little Cr element in 45# carbon steel, so there was no sharp increase of NOx.

The aim of this study was to investigate the effects of dietary supplementation with two alternatives to antibiotics (Candida tropicalis and mulberry leaf flavonoids) on intestinal microbiota of preweaned calves challenged with Escherichia coli K99. Sixty Holstein calves were randomly assigned to 5 treatments: fed a basal diet (N-CON); fed a basal diet and challenged with E.coli K99 (P-CON); fed a basal diet supplemented with C.tropicalis (CT), mulberry leaf flavonoids (MLF), and the combination of the two additives (CM), respectively, and challenged with E.coli K99. The MLF and CM groups had significantly higher average daily grain and feed efficiency, and significantly lower fecal scores compared with the P-CON group after E. coli K99 challenge. The supplementation groups increased the relative abundance, at the phylum level, of Bacteroidetes and Proteobacteria, whereas at the genus level, they increased the relative abundance of Prevotella, Lactobacillus, and Enterococcus. Quantitative PCR revealed that the CT, MLF, and CM groups had significantly lower copy numbers of E.coli K99 compared with the P-CON group. The CT, MLF, and CM treatments reduce days of diarrhea, improve intestinal health, and beneficially manipulate the intestinal microbiota in preweaned calves.

In order to know whether the NO x pollution is caused by solar salt in solar thermal power generation, this work aimed at investigating the effects of nickel base alloy on NO x emissions in thermal energy storage (TES) process of solar salt (an eutectic salt mixture with the component of 60%NaNO 3 -40%KNO 3 ), and based on this, determining the optimized temperature range of solar salt in nickel base alloy loop materials. According to the national environmental protection standard of PR China, HJ479-2009, the concentrations of NO/NO 2 net emissions in tail gases from the heated molten salts while contacting with Inconel 625(In625), Hastelloy C276 (Has C276) and Hastelloy X (Has X) were measured in TES process, which were deducted the influence of platinum boat while contacting with the molten nitrates. Furthermore, the chemical thermodynamic calculations of related reactions that Cr, Ni, Mo, W with nitrate salts were carried out to explain the NO/NO 2 coming from. The test results show that solar salt contained in pipes or tanks made of nickel base alloy under air atmosphere in certain conditions can release NO x in its usage temperature range, and the concentrations of NO x emissions increase with the rise of the temperature. Below 500 C, the concentrations of NO x net emissions that solar salt contacting with these three kinds of nickel base alloys are under 200 mg/m 3 , which is in accordance with the emission limit of thermal power plant in China and the emission limit of second directive of EU in coal-fired power plant. Besides, the concentrations of NO net emission were almost larger than NO 2 between 300 C and 550 C, which may be caused by Mo and W component in nickel base alloy.

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The objective of this work is to investigate the NO x emissions from HITEC (ternary molten nitrates of 7 wt.%NaNO 3 -53 wt.%KNO 3 -40 wt.%NaNO 2 ) in thermal energy storage (TES) process and the effects of 45 # carbon steel (1045, ASTM) on NO x emission as well as the component changes in HITEC. Referring to the national environmental protection standard (HJ479-2009) in China, NO x emissions in tail gases were measured in one hour for heating the molten salts in a quartz glass boat during TES process. Furthermore, the concentrations of nitrate and nitrite ion in molten salts samples were determined, and chemical thermodynamic calculations of related reactions were carried out to explain the mechanism of NO x emissions. The results show that HITEC contained in a quartz glass or carbon steel container in air atmosphere can release NO x in the operating temperature range, which were caused by several reactions between nitrate and SiO 2 or Fe. The concentrations of NO x emissions increase with the rise of temperature. In the practical application, NO x emission is acceptable since the amount of NO 2 or NO will dramatically decreased in the liquid salts by reacting with NaNO 2 .

Proliferation of shrubs at the expense of native forage in pastures has been associated with large changes in biomass and spatial distribution of forage for grazing livestock, and such changes influence the grazing behavior of ruminants. However, little information is available concerning the effect of pastoral shrub coverage on grazing pattern. To better understand the grazing behavior of yaks and their response to increased shrub coverage in alpine meadows, 48 yak steers were randomly assigned to four pastures with shrub coverage of 0, 5.4 %, 11.3 %, and 20.1 % (referred to as control, low, middle, and high, respectively) on the Qinghai-Tibetan Plateau. The primary behavioral patterns (grazing, walking, and ruminating/resting) of three focus animals per experimental group were recorded repeatedly in scan sampling every 10 min from 07:00 to 19:00 h in three observation periods (the first 10 days of each month) from July through September. Furthermore, the secondary behavioral patterns (bites per minute, steps per minute, and bites per step) were observed 15 times per focus yak on each observation day. Behavioral observations showed that yaks had similar diurnal behavioral patterns with two main grazing bouts—in the morning and afternoon—and a ruminating/resting peak at midday when grazing in pastures with different shrub coverage. However, yaks significantly enhanced the time allocated to walking (P = 0.029) and decreased ruminating/resting time (P = 0.045) with increasing shrub coverage, although the grazing time was not significantly different (P = 0.663). Compared with the control and low shrub-coverage groups, yaks in the middle and high groups had more bites per minute (P = 0.036) and steps per minute (P = 0.029), whereas the number of bites per step was not influenced (P = 0.877) by shrub coverage. The increased time allocated to walking at the expense of ruminating/resting as well as the high number of feeding stations may be an adaptive strategy for searching and obtaining sufficient forage resources. Increased walking time and step rate for the yaks grazing in the high shrub-coverage pasture could increase the energy expenditure and consequently reduce the energy available for growth and production. Our findings provide evidence for the influence of shrub coverage on grazing behavior of yaks grazing in alpine meadows as well as insights into the sustainable production of grazing yaks on lands with increasing shrub coverage on the Qinghai-Tibet Plateau.

To better utilize native pasture at the high altitude region, three-consecutive-year feeding experiments and a total of seven metabolism trials were conducted to evaluate the impact of three forage stages of maturity on the chemical composition, nutrient digestibility, and energy metabolism of native forage in Tibetan sheep on the Qinghai–Tibetan Plateau (QTP). Forages were harvested from June to July, August to October, and November to December of 2011 to 2013, corresponding to the vegetative, bloom, and senescent stages of the annual forages. Twenty male Tibetan sheep were selected for each study and fed native forage ad libitum. The digestibility of DM, OM, CP, NDF, ADF, DE, DE/GE, and ME/GE were greatest (P < 0.01) from the vegetative stage, intermediate (P < 0.01) from the bloom stage, and least (P < 0.01) from the senescent stage. Nutrient digestibility and energy parameters correlated positively (linear, 0.422 to 0.778; quadratic, 0.568 to 0.815; P < 0.01) with the CP content of forage but correlated negatively with the content of NDF (linear, 0.343 to 0.689; quadratic, 0.444 to 0.777; P ≤ 0.02), ADF (linear, 0.563 to 0.766; quadratic, 0.582 to 0.770; P < 0.01), and ether extract (EE, linear, 0.283 to 0.574; quadratic, 0.366 to 0.718; P ≤ 0.04) of forage. For each predicted variable, the prediction of DMI expressed as grams per kilogram of BW (g/kg BW·d) yielded a greater R(2) value (0.677 to 0.761 vs. 0.616 to 0.711) compared with the equations of DMI expressed as g/kg metabolic BW by step-wise regression. The results suggest that parameters of forage CP, NDF, and ADF content were most closely related to nutrient digestibility. Contrary to previous studies, in this study, ADF content had a greater linear relationship (0.766 vs. 0.563 to 0.732) with OM digestibility than the other parameters of nutrient digestibility. The quadratic relationship between forage CP content and CP digestibility indicates that when forage CP content exceeds the peak point (9.7% DM in the present study), increasing forage CP content could decrease CP digestibility when Tibetan sheep were offered native forage alone on the QTP. Additionally, using the forage CP, EE, NDF, and ADF content to predict DMI (g/kg BW·d) yielded the best fit equation for Tibetan sheep living in the northeast portion of the QTP.

This study investigated the effects of protein sources for milk replacers on growth performance and serum biochemical indexes of suckling calves. Fifty Chinese Holstein bull calves with similar BW and age were randomly allocated to 5 groups (1 control and 4 treatments) of 10 calves in each group. Five types of milk replacers were designed to have the same level of energy and protein. The protein source for milk replacers of the control group was full milk protein (MP). The protein source of milk replacers of the 4 treatment groups was composed of MP and one vegetable protein (VP) (30 and 70% of total protein). The 4 types of VP were soybean protein concentrate (SP), hydrolyzed wheat protein (WP), peanut protein concentrate (PP), and rice protein isolate (RP). Results of the experiment showed: 1) there was no significant difference on average daily gain (ADG) and feed:gain ratio (F:G) among the MP, SP and RP groups (P > 0.05), whereas the ADG and F:G of the WP and PP groups were significantly lower compared with the MP group (P 0.05). Thereby the 4 VP milk replacers had no adverse effects on body size of calves; 3) all groups showed no significant difference in the serum contents of urea nitrogen, total protein, albumin, globulin, β-hydroxybutyrate, growth hormone, insulin-like growth factor-1, and the ratio of albumin to globulin (A:G) (P > 0.05). In conclusion, SP or RP (accounts for 70% of the total protein) as calf milk replacers could substitute MP, whereas wheat gluten and PP had a significant adverse effect on growth performance in this experiment.

Background: Hydrogen sulfide (H2S) protects against acute myocardial ischemia/reperfusion (MI/R) injury and heart failure by ameliorating oxidative stress, improving mitochondrial function, and attenuating apoptosis. One of the major limitations of currently available H2S donors is poor pharmacokinetics profiles that result in very rapid and uncontrolled H2S release. NSHD-1 and NSHD-2 are recently developed thiol-activated H2S donors designed for sustained release of H2S upon activation by molecules containing thiol groups such as cysteine and glutathione. We hypothesized that these novel H2S donors would generate H2S for extended periods and ameliorate myocardial cell death following MI/R in an in vivo murine model. Methods and Results: C57BL6/J male mice (10-12 weeks of age) were subjected to 45 minutes of MI followed by 24 hours of R. At the time of reperfusion, animals received Vehicle (0.5% THF), NSHD-1 (50 μg/kg and 100 μg/kg), or NSHD-2 (50 μg/kg) by direct intracardiac (i.c.) injection. In addition, at 4 hours of R, plasma was collected for troponin-I measurements. In preliminary studies we observed sustained release of H2S with both of these H2S donors. Myocardial infarct size was reduced by 35% (p < 0.01 vs. Vehicle) in mice treated with NSHD-1 (100 μg/kg), 43% (p < 0.05 vs. Vehicle) in mice treated with NSHD-2 (50 μg/kg), and 54% (p < 0.01 vs. Vehicle) in mice treated with NSHD-2 (100 μg/kg). Conclusions: NSHD-1 and NSHD-2 significantly attenuate MI/R injury in a murine model. Experiments are currently underway to further define the in vivo pharmacokinetics of H2S release from these agents, mechanisms of action, and safety profile.

A type N coaxial load for the RF calorimeter is proposed in this paper. Some key technology is researched such as load resistance and tractrix outer-conductor. In order to get a calorimeter-load of high stability, the thermal simulation and analysis are conducted. The test results validate not only the matched performance of the load is excellent, but also the responses of RF power and DC power are consistent. A highly RF-DC substitutive load is achieved.

The method for retrieving the ocean wave spectrum from the Synthetic Aperture Radar (SAR) imagery is currently the most widely used for calculation of the wave high, wavelength and wave direction. However the most current of methods are relatively complicated. This paper presents an algorithm which is based on Radon transform. In this algorithm, firstly, with the property of Radon transform that the line in the SAR image and the point in the transformed space are one-to-one correspondence, the texture feature of the wave in SAR image is detected to calculate the wavelength and probable wave direction. Secondly, according to the theory of the ocean wave and the trends of the wavelength in two close sub-images, the actual wave direct ion is determined eventually. This article selects an ERS - 2 SAR image around Taiwan as the study area. The results of calculation are compared with the results obtained by Two-Dimensional Fast Fourier Transform (2D- FFT). The study results demonstrate that the use of the Radon transform is available without loss of the accuracy when retrieving the wave wavelength and wave direction from the ERS-2 SAR images.