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A 2-year fertilization experiment was conducted to study the effect of different ratios of organic (pig) manure on wheat yield and nitrogen use efficiency (NUE). The four treatments were no nitrogen (N) (CK); 100% chemical fertilizer N (urea; T1); 70% chemical fertilizer N + 30% organic manure N (T2) and 50% chemical fertilizer N + 50% organic manure N (T3), with the same amount of applied nitrogen (120 kg/ha). The results showed the maximum grain yield (3049 kg/ha), crop nitrogen uptake (216 kg/ha), NUE (65.4%) and accumulated nitrate nitrogen (NO3−-N in 0–200 cm, 142 kg/ha) were observed in the T1 among all treatments in the first year. However, the largest grain yield (5074 kg/ha), crop nitrogen uptake (244 kg/ha) and NUE (82.5%) were under T2 treatment in the second year. Furthermore, T2 had the maximum NO3−-N content in 0–100 cm layer (116 kg/ha), especially 0–40 cm layer, and the lowest NO3−-N content in 100–200 cm (58.8 kg/ha). However, 50% organic manure N in T3 increased apparent nitrogen loss by 39.0% compared to that in T2. Therefore, 30% organic manure N application was more conducive for enhancing wheat yield and NUE and promoting environmental safety after 1-year fertilization time.
There is limited information concerning the viral load of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in aerosols deposited on environmental surfaces and the effectiveness of infection prevention and control procedures on eliminating SARS-CoV-2 contamination in hospital settings. We examined the concentration of SARS-CoV-2 in aerosol samples and on environmental surfaces in a hospital designated for treating severe COVID-19 patients. Aerosol samples were collected by a microbial air sampler, and environmental surfaces were sampled using sterile premoistened swabs at multiple sites. Ninety surface swabs and 135 aerosol samples were collected. Only two swabs, sampled from the inside of a patient's mask, were positive for SARS-CoV-2 RNA. All other swabs and aerosol samples were negative for the virus. Our study indicated that strict implementation of infection prevention and control procedures was highly effective in eliminating aerosol and environmental borne SARS-CoV-2 RNA thereby reducing the risk of cross-infection in hospitals.
Previous work led to the proposal that the precision feeding of a high-concentrate diet may represent a potential method with which to enhance feed efficiency (FE) when rearing dairy heifers. However, the physiological and metabolic mechanisms underlying this approach remain unclear. This study used metabolomics analysis to investigate the changes in plasma metabolites of heifers precision-fed diets containing a wide range of forage to concentrate ratios. Twenty-four half-sib Holstein heifers, with a similar body condition, were randomly assigned into four groups and precision fed with diets containing different proportions of concentrate (20%, 40%, 60% and 80% based on DM). After 28 days of feeding, blood samples were collected 6 h after morning feeding and gas chromatography time-of-ﬂight/MS was used to analyze the plasma samples. Parameters of oxidative status were also determined in the plasma. The FE (after being corrected for gut fill) increased linearly (P < 0.01) with increasing level of dietary concentrate. Significant changes were identified for 38 different metabolites in the plasma of heifers fed different dietary forage to concentrate ratios. The main pathways showing alterations were clustered into those relating to carbohydrate and amino acid metabolism; all of which have been previously associated with FE changes in ruminants. Heifers fed with a high-concentrate diet had higher (P < 0.01) plasma total antioxidant capacity and superoxide dismutase but lower (P ≤ 0.02) hydroxyl radical and hydrogen peroxide than heifers fed with a low-concentrate diet, which might indicate a lower plasma oxidative status in the heifers fed a high-concentrate diet. Thus, heifers fed with a high-concentrate diet had higher FE and antioxidant capacity but a lower plasma oxidative status as well as changed carbohydrate and amino acid metabolism. Our findings provide a better understanding of how forage to concentrate ratios affect FE and metabolism in the precision-fed growing heifers.
Microvascular health is a main determinant of coronary blood flow reserve and myocardial vascular resistance. Extracardiac capillary abnormality has been reported in subjects at increased coronary heart disease risk, such as prehypertension, hypertension, diabetes, hyperlipidemia, and atherosclerosis. We have reported cardiovascular dysfunction in a cohort of maternal nutrient reduction (MNR)-induced intrauterine growth restriction (IUGR) baboon offspring. Here we test the hypothesis that there is oral capillary rarefaction associated with MNR-induced IUGR. Capillary density was quantified using in vivo high-power capillaroscopy on seven middle-aged (~10.7 yr; human equivalent ~40 yr) male IUGR baboons and seven male age-matched controls in the lateral buccal and inferior labial mucosa. While no difference was found between groups in either area by fraction area or optical density for these vascular beds derived from fetal preductal vessels, further studies are needed on post-ductal vascular beds, retina, and function.
The main design activity in engineering practice is to adapt existing designs or to create variants of existing products to new demands, which require a robust model against both parametric and topological changes. To design such a kind of model becomes a big challenge, especially in the development of structural components due to the number of load application points, variable load cases and restrictions from manufacturing technologies. Thus, the generative parametric design approach is applied to generating high dynamic product models, allowing them to be adjusted for changes feasibly.
In this paper, the generation of relativistic electron mirrors (REM) and the reflection of an ultra-short laser off the mirrors are discussed, applying two-dimension particle-in-cell simulations. REMs with ultra-high acceleration and expanding velocity can be produced from a solid nanofoil illuminated normally by an ultra-intense femtosecond laser pulse with a sharp rising edge. Chirped attosecond pulse can be produced through the reflection of a counter-propagating probe laser off the accelerating REM. In the electron moving frame, the plasma frequency of the REM keeps decreasing due to its rapid expansion. The laser frequency, on the contrary, keeps increasing due to the acceleration of REM and the relativistic Doppler shift from the lab frame to the electron moving frame. Within an ultra-short time interval, the two frequencies will be equal in the electron moving frame, which leads to the resonance between laser and REM. The reflected radiation near this interval and corresponding spectra will be amplified due to the resonance. Through adjusting the arriving time of the probe laser, a certain part of the reflected field could be selectively amplified or depressed, leading to the selective adjustment of the corresponding spectra.
Considering the decision-making requirements of airport, airlines and passengers, a bilevel programming model which contains two parts was proposed in this paper. One part is to improve the utilization of gates of the airport (upper level), so the objective function of the upper level to the minimum overall variance of slack time between two consecutive air crafts at the same gate. The other part looks at maximize the airline revenue and passengers more conveniently and comfortably (lower level). The lower level has two objective functions — the minimum passenger transfer failure and the minimum passenger average transfer time, respectively. According to the latest data of an airport in Eastern China, the adaptive genetic algorithm is used to solve the above-mentioned bilevel optimisation problems. The numerical experiment shows that the model not only reduces the variance of the relaxation time, but also optimises the flight gate allocation and achieves the initial goal.
Reducing dietary CP content is an effective approach to reduce animal nitrogen excretion and save protein feed resources. However, it is not clear how reducing dietary CP content affects the nutrient digestion and absorption in the gut of ruminants, therefore it is difficult to accurately determine how much reduction in dietary CP content is appropriate. This study was conducted to investigate the effects of reduced dietary CP content on N balance, intestinal nutrient digestion and absorption, and rumen microbiota in growing goats. To determine N balance, 18 growing wether goats (25.0 ± 0.5 kg) were randomly assigned to one of three diets: 13.0% (control), 11.5% and 10.0% CP. Another 18 growing wether goats (25.0 ± 0.5 kg) were surgically fitted with ruminal, proximate duodenal, and terminal ileal fistulae and were randomly assigned to one of the three diets to investigate intestinal amino acid (AA) absorption and rumen microbiota. The results showed that fecal and urinary N excretion of goats fed diets containing 11.5% and 10.0% CP were lower than those of goats fed the control diet (P < 0.05). When compared with goats fed the control diet, N retention was decreased and apparent N digestibility in the entire gastrointestinal tract was increased in goats fed the 10% CP diet (P < 0.05). When compared with goats fed the control diet, the duodenal flow of lysine, tryptophan and phenylalanine was decreased in goats fed the 11.5% CP diet (P < 0.05) and that of lysine, methionine, tryptophan, phenylalanine, leucine, glutamic acid, tyrosine, essential AAs (EAAs) and total AAs (TAAs) was decreased in goats fed the 10.0% CP diet (P < 0.05). When compared with goats fed the control diet, the apparent absorption of TAAs in the small intestine was increased in goats fed the 11.5% CP diet (P < 0.05) and that of isoleucine, serine, cysteine, EAAs, non-essential AAs, and TAAs in the small intestine was increased in goats fed the 10.0% CP diet (P < 0.05). When compared with goats fed the control diet, the relative richness of Bacteroidetes and Fibrobacteres was increased and that of Proteobacteria and Synergistetes was decreased in the rumen of goats fed a diet with 10.0% CP. In conclusion, reducing dietary CP content reduced N excretion and increased nutrient utilization by improving rumen fermentation, enhancing nutrient digestion and absorption, and altering rumen microbiota in growing goats.
The Bai language () is spoken by approximately 1.6 million people in northwest Yunnan Province, China. Of the 25 minority languages spoken in Yunnan, where 33% of the population are ethnic minorities and 67% are Han Chinese, the Bai ethnic minority is second in population only to the Yi (Wiersma 1990, 2003; 2010 census). Bai is classified as a Tibeto-Burman language (Xu & Zhao 1964, 1984), although arguments have been raised as to its possible early Sinitic origins (Starostin 1994, 1995). A summary in French reviews Chinese loanwords, ancient Bai, and comparative Bai dialects (Dell 1981). The historical influence of Chinese on Bai has been significant, but evidence is not compelling that Bai is Sinitic (Norman 2003: 73). There are three major dialects of Bái: Jiànchuān (), Dàlĭ (), and Bìjiāng (). The data in this illustration represent the variety of Jianchuan (jian1239, BCA). The third author (), who was about 60 years old at the time of recording, is a male native of the Jianchuan region, originating from QiÁohǒu, a mountain village some 50 km southwest of Jianchuan city – a remote area known for salt mining and where the language has been less influenced by modern Chinese. These locations are indicated on the map of Yunnan (the southwesternmost province of China in an intensely minority-language-populated area) in Figure 1. The traditional geographical link from Qiaohou is to Jianchuan to the north rather than to Dali to the south, and many of the most distinctive characteristics of Jianchuan Bai described here are not found in Dali Bai.
Thermal barrier coating is a high-temperature protective technology widely used in industrial gas turbines. However, the failure of coating peeling because of the generation of thermally grown oxide (TGO) at the interface during service hinders its further application. In this study, Raman spectroscopy and wedge indentation are used to determine the TGO residual stress and the interface energy release rate, respectively. The effect of TGO on the interfacial fracture toughness during the growth process was discussed. Raman spectroscopy test results show that the residual stress of TGO is about 0.5 GPa. Wedge indentation test results illustrate that high-temperature heat treatment could accelerate the interface degradation of thermal barrier coatings. Stress analysis and test research demonstrate that the microcracks induced by compressive stress of TGO will propagate with increasing heating time, ending with failure of barrier coatings.
There seems to be geographical differences in decisions about breast conserving surgery (BCS) in breast cancer patients. This study was to evaluate patients’ attitude to BCS and to assess the factors affecting cancer practice in West China.
A structured questionnaire was distributed to 184 patients, eliciting information about the patients’ characteristics, occupation, education, family life, recognition of illness, knowledge about BCS, the main means of gaining surgery information, selecting surgery approaches, preferences to breast reservation.
In all, 163 patients completed the questionnaire. The results indicated that only 7.4% of patients received BCS and 23% of the remaining patients desired to have BCS and the affecting factors were significantly associated with their family life, recognition of illness and the main means of gaining surgery information (P < 0.05). No associations were between BCS selecting and the other variables studied. The most frequent reasons for selecting BCS were keeping the female shape and improving quality of life (71%), the second most were postoperative recovery, minimal influence of physical function (47%) and patients’ knowledge about BCS (42%). The most frequent reasons for not selecting BCS were uncertainty about BCS results and worry about recurrence (81%), the second most was the elderly age unnecessary for BCS (40%).
The findings indicate that breast cancer patients in West China do not take BCS as the first choice as the best treatment method. It is warranted that further study of more patients, attitude of patients’ partners and physicians to BCS.
Attention, working memory (WM), information processing and memory deficits are important features of schizophrenia. WM functions appear to be mediated by the dorsolateral prefrontal cortex (DLPFC). Functional imaging studies have shown a failure to activate the DLPFC during working memory tasks in patients with chronic schizophrenia. The primary aim of this study is to determine whether there are brain activation changes in the dorso-lateral prefrontal cortex (DLPFC) as a result of engaging in a randomized, controlled 12 week course of cognitive remediation therapy (CRT) in inpatients with chronic schizophrenia.
Patients with DSM IV schizophrenia are randomized to a 12 week trial of Cognitive Remediation (CR) using a Computerized CR program (COGPACK) or to a 12-week control condition. Patients receive at baseline and endpoint an fMRI scan with a cognitive task (N-back task), a neuropsychological test battery (MATRICS), functional and symptom assessments.
Preliminary results of this ongoing study show that patients after 12 weeks of CR showed (1) significantly more improvement in WM functions than patients who participated in the control group and (2) improvement in accuracy on the verbal letter 2-back task during the fMRI scan. Signal difference between 2-back and 0-back was not present or only present minimally at baseline (Pre-CR); however, at endpoint (Post-CR) there was signal difference present, which corresponds to an increase in activation in the areas of the DLPFC. This increase in activation pattern may be reflective of the effects of the exposure to the CR intervention.
To compare therapeutic efficacy, social function, discontinue rate, relapse and recurrence rate of the depression outpatients with first episode between Venlafaxine extended release and Fluoxertine hydrochloride treatment. Methods In this 48 week natural parallel follow-up study, total 188 patients who meet ICD-10 criteria for a major depressive episode were admitted and assigned to receive either Venlafaxine Extended Release (Venlafaxine XR group) (n=89) or Fluoxertine hydrochloride(Fluoxertine group) (n=99).At baseline,week2,8,12,16,24,32,48,Hamilton Rating Scale for Depression (HAMD)-17 item was used to value disease severity, and Social Disability Screening Schedule(SDSS)for social disability, and the discontinue, relapse and recurrence rates were compared. Results (1) At week 24 Venlafaxine XR group had much lower HAMD17 total score than Fluoxertine group (P<0.05). (2)The remission rate and response rate between two groups had no statistical difference (P>0.05). (3) At week 12, Venlafaxine XR group had a higher SDSS score than Fluoxertine group (P<0.05).(4)At week 12, 16, 24, 32,48,Venlafaxine XR group displayed lower discontinue rates (P<0.05). Venlafaxine XR group had a longer treatment course than Fluoxertine did [(30.99±15.98) weeks vs. [(22.57±15.26) weeks] (P<0.01). (5) The relapse and recurrence rates of two groups had no statistical difference (P>0.05). Conclusions In the acute phase, Venlafaxine XR has a better effect for social function and treatment adherence than Fluoxertine hydrochloride. In the continued phase and sustained phase, Venlafaxine XR performs better for symptoms relief and treatment adherence.Venlafaxine XR has parallel performance with Fluoxertine hydrochloride by the terms of therapeutic efficacy, social function restore, relapse and recurrence rate.
Modafinil was tested for efficacy in facilitating abstinence in cocaine-dependent patients, compared to placebo.
This is a double-blind placebo-controlled study, with 12 weeks of treatment and a 4-week follow-up. 210 treatment-seekers with DSM-IV diagnosis of cocaine dependence consented and enrolled. 72 participants were randomized to placebo, 69 to modafinil 200mg, and 69 to modafinil 400mg, taken once daily on awakening. Participants attended the clinic three times per week for assessments and urine drug screens, and had one hour of individual psychotherapy once per week. The primary outcome was the increase in weekly percentage of non-use days. Secondary outcomes included: decrease in the weekly median log of urine benzoylecgonine, subgroup analyses of balancing factors and co-morbid conditions, self-report of alcohol use, addiction severity, craving, and risk behaviors for HIV.
125 participants completed 12 weeks of treatment (60%). The GEE regression analysis showed that for the total sample, the difference between modafinil groups and placebo in the weekly percentage of cocaine non-use days over the 12-week treatment period was not statistically significant (p=0.95). A post-hoc analysis showed a significant effect for modafinil, only in the subgroup of cocaine patients without alcohol dependence. Modafinil 200mg also showed significant effects of an increase in the total number of consecutive non-use days for cocaine (p=0.02), and a reduction in craving (p=0.04).
These data suggest that modafinil, in combination with individual behavioral therapy, was effective for increasing cocaine non-use days in participants without co-morbid alcohol dependence, and in reducing craving.