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Application of organic nitrogen (N) has been proposed as a method to reduce potential environmental pollution due to N loss without sacrificing grain yield. The mechanism responsible for organic N regulation of maize (Zea maysL.) N metabolism is nonetheless largely unknown. In this study, we compared the expression of genes related to N assimilation and remobilization during the grain filling stage in maize plants grown under field conditions. We applied five different N treatments, which consisted of N supplied in organic and/or inorganic forms at the following rates: 0/45, 0/120, 0/240, 120/120, and 240/0 kg ha−1organic/inorganic N. Yield was found to increase with increasing N input, but no significant difference was found in grain yield among 0/240, 240/0 and 120/120 treatments. Organic N application tended to decrease N accumulation and to increase N utilization efficiency. Genes related to N assimilation activity in leaves, such asZmNR1andZmFd-GOGAT1, were unaffected by different N forms. In contrast, genes related to N remobilization activity in leaves, such asZmGS1.1andZmGDH1, were up-regulated, especially in old leaves, by the pure organic N supply treatment (240/0). These data suggest that application of pure organic N likely induces a N-deficiency response in maize plants, with a consequent increase in physiological N utilization efficiency due to up-regulation of key genes involved in N remobilization processes. [ABSTRACT FROM PUBLISHER]

A new Briggs Rauscher oscillating reaction with a tetraazamacrocyclic nickel(II) complex [NiL](ClO) as catalyst and pentane-2,4-dione (pe) as the substrate is reported. The ligand L is 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradeca-4,11-diene. The experimental results indicate that iodine ion may be an important intermediate, and free radicals can be involved in the reaction. A tentative mechanism based on Noyes Furrow model ( NF model) is proposed. Moreover, other factors, such as the variation of concentration of the components and temperature on the oscillator, are discussed. [ABSTRACT FROM AUTHOR]

Background: Lumbar intervertebral disc and paravertebral muscle degeneration are common causes of chronic low back pain (CLBP). However, the exact etiology of CLBP in young patients remains unclear. Identifying the risk factors for CLBP in young patients could expedite the development of effective preventive recommendations. Objectives: To identify the factors influencing the presence and severity of CLBP in young patients by analyzing the associations between the fat content of the paravertebral muscles, T2 value of the lumbar intervertebral disc (LIVD), and visual analog scale (VAS) score. Design: Data for 23 patients diagnosed with CLBP were compared to those of 20 healthy young individuals. Methods: The T2 values of the LIVD and fat content of the psoas major (PM), multifidus (MF), and erector spinae (ES) muscles for 23 young patients with CLBP and 20 healthy individuals were measured and compared using synthetic magnetic resonance imaging and proton density fat fraction analyses. Moreover, the factors (T2 values and fat content) associated with severe CLBP (assessed using the VAS score) were analyzed. Results: The fat content of the right MF and ES was higher in patients with CLBP than in healthy individuals ( p 0.05). Moreover, the VAS scores did not correlate with the T2 values of the patients ( p > 0.05). The fat content of the bilateral MF and ES muscles was positively associated with the VAS score in young patients with CLBP (left MF: r = 0.506, p = 0.01; right MF: r = 0.532, p = 0.01; left ES: r = 0.636, p

The microstructural evolution of Ti-45 at.%Al alloy during directional solidification was simulated by applying a solute diffusion controlled solidification model. The obtained results have shown that under high thermal gradients the stable primary spacing can be adjusted via branching or competitive growth. For dendritic structures formed under a high thermal gradient, the secondary dendrite arms are developed not very well in many cases due to the branching mechanism under a constrained dendritic growth condition. Furthermore, it has been observed that, with increasing pulling velocity, there exists a cell/dendrite transition region consisting of cells and dendrites, which varies with the thermal gradient in a contradicting way, i.e. increase of the thermal gradient leading to the decrease of the range of the transition region. The simulations agree reasonably well with experiment results.

The FDM numerical simulation software, ViewCast system, was employed to simulate the low pressure die casting (LPDC) of an aluminum wheel. By analyzing the mold-fi lling and solidifi cation stage of the LPDC process, the distribution of liquid fraction, temperature field and solidification pattern of castings were studied. The potential shrinkage defects were predicted to be formed at the rim/spoke junctions, which is in consistence with the X-ray detection result. The distribution pattern of the defects has also been studied. A solution towards reducing such defects has been presented. The cooling capacity of the mold was improved by installing water pipes both in the side mold and the top mold. Analysis on the shrinkage defects under forced cooling mode proved that adding the cooling system in the mold is an effective method for reduction of shrinkage defects.

Shrinkage defects can be formed easily at Critical location during low pressure die casting (LPDC) of aluminum alloy cylinder body. It has harmful effect on the products. Mold fi lling and solidifi cation process of a cylinder body was simulated by using of Z-CAST software. The casting method was improved based on the simulation results. In order to create effective feeding passage, the structure of casting was modifi ed by changing the location of strengthening ribs at the bottom, without causing any adverse effect on the part’s performance. Inserting copper billet at suitable location of the die is a valid way to create suitable solidifi cation sequence that is benefi cial to the feeding. Using these methods, the shrinkage defect was completely eliminated at the critical location.

The microstructure, precipitate type, precipitate distribution and tensile strength of a ZL205 alloy, before and after ageing treatment, have been studied by means of optical microscopy and transmission electron microscopy. The results showed that the as-cast microstructure of the alloy was made up of α-Al and eutectic phase distributed at the grain boundaries. During ageing treatment, the tensile strength increased at first and then reduced with time, and the highest ultimate tensile strength was found to be around 488.2 MPa.

The apparent rate coefficients for the electron-impact excitation from argon 1s to 3p states are determined in the electron temperature (Te) range of 0.8 to 1.2 eV, in the afterglow of a capacitive argon discharge by using the temporal behavior of different state densities. The measured parameters include the densities of the 3p states (by optical emission), the densities of the four argon 1s states (by diode laser absorption) and Te (by a Langmuir probe and a line-ratio technique). Among the 24 rate coefficients obtained in this work, the results for excitation from the two resonance states (1s2 and 1s4) are reported here for the first time. As for the excitation from the two metastable states (1s3 and 1s5), the measured rate coefficients are compared with the available values from the distorted wave method and the electron beam experiment. [ABSTRACT FROM AUTHOR]

Background: Invasive blood pressure (IBP) measurement is common in the intensive care unit, although its association with in-hospital mortality in critically ill patients with hypertension is poorly understood.Methods and Results: A total of 11,732 critically ill patients with hypertension from the eICU-Collaborative Research Database (eICU-CRD) were enrolled. Patients were divided into 2 groups according to whether they received IBP. The primary outcome in this study was in-hospital mortality. Propensity score matching (PSM) and inverse probability of treatment weighing (IPTW) models were used to balance the confounding covariates. Multivariable logistic regression was used to evaluate the association between IBP measurement and hospital mortality. The IBP group had a higher in-hospital mortality rate than the no IBP group in the primary cohort [238 (8.7%) vs. 581 (6.5%), p < 0.001]. In the PSM cohort, the IBP group had a lower in-hospital mortality rate than the no IBP group [187 (8.0%) vs. 241 (10.3%), p = 0.006]. IBP measurement was associated with lower in-hospital mortality in the PSM cohort (odds ratio, 0.73, 95% confidence interval, 0.59–0.92) and in the IPTW cohort (odds ratio, 0.81, 95% confidence interval, 0.67–0.99). Sensitivity analyses showed similar results in the subgroups with high body mass index and no sepsis.Conclusions: In conclusion, IBP measurement was associated with lower in-hospital mortality in critically ill patients with hypertension, highlighting the importance of IBP measurement in the intensive care unit.

Objective To investigate the rate and correlates of receiving human immunodeficiency virus(HIV) serostatus disclosure from their most recent male sexual partners among men who have sex with men(MSM) aged 50 and above. Methods With a geosocial networking application,we recruited participants through online convenience sampling to collect the demographic variables,behavioral information,receiving HIV serostatus disclosure,etc.Univariate and multivariate analyses were performed to interpret the associated factors of receiving HIV serostatus disclosure. Results Overall,38.4%(398/1037) of participants received HIV serostatus disclosure from their most recent male sexual partners.The multivariable analysis demonstrated that the following populations were less likely to receive HIV serostatus disclosure from their most recent male sexual partners:participants with junior high school degree or below( OR =0.660,95% CI =0.473-0.922, P =0.015) compared to those with senior high school degree or above;participants unemployed( OR =0.537,95% CI =0.322-0.896, P =0.017) and employed( OR =0.663,95% CI =0.466-0.944, P =0.022) compared to those retired;participants without knowledge about HIV or acquired immune deficiency syndrome(AIDS) compared to those with knowledge about HIV/AIDS( OR =0.636,95% CI =0.466-0.868, P =0.004);participants having ≥2 male sexual partners in the last year( OR =0.433,95% CI =0.320-0.586, P <0.001) compared to those having none or one male sexual partner;participants never been tested for HIV( OR =0.544,95% CI =0.403-0.734, P <0.001) compared to those ever been tested for HIV;participants ever been diagnosed to have sexually transmitted infection(STI)( OR =0.472,95% CI =0.349-0.637, P <0.001) compared to those never diagnosed to have STI;and participants with higher level of HIV stigma( OR =0.742,95% CI =0.604-0.912, P =0.005). Conclusions Our findings indicated that the MSM aged 50 and above had low possibility of receiving HIV serostatus disclosure from the most recent male sexual partners.Education,employment status,number of sexual partners,HIV/AIDS-related knowledge,HIV testing behaviors,STI infection history,and HIV stigma contributed to this result.

The application of microbial fertilizer plays an important role in improving soil restoration and fertilizer utilization. The effects of microbial fertilizer are greatly affected by crop genotypes and ecological conditions. Little is known about the effects of microbial fertilizers on maize production in Northeast China. To develop microbial fertilizer specific to the black soil and the climate characteristics of Northeast China, we isolated five plant rhizosphere-promoting bacteria (PGPR), named as MZ1, MZ2, MZ3, MZ4 and MZ5, with different degrees of biological functions such as IAA synthesis, phosphate-solubilizing, potassium-solubilizing and siderophore-releasing, from the rhizosphere of maize field. The analysis of ecological adaptability showed that those five strains differed in salt resistance, drought tolerance, acid and alkali resistance, pesticide resistance. The 16S rRNA gene sequences analysis showed that the strains MZ1, MZ2, MZ3, MZ4 and MZ5 belonged to the genus of Sphingomonas, Enterobacter, Pseudomonas, Bacillus and Rhizobium, respectively. In maize field experiment with 50% nitrogen fertilizer reduction, the inoculation with MZ1, MZ3 and MZ5 increased grain yield by 19.9%-25.0%. MZ1, MZ3, and MZ5 could be used as microbial fertilizers for maize in Northeast China.

Objective: To explore the associated factors on loss to follow-up among men who have sex with men (MSM) in a prospective cohort study., Methods: We recruited eligible HIV-negative MSM at baseline in eight cities from June to October 2009. Interviewer-administrated questionnaire and blood testings for HIV, syphilis and human simplex virus type 2, were accomplished upon enrollment, 6-month and 12-month follow-up visits in the program. Loss to follow-up was recorded at each visit in this cohort. Univariate and multivariate statistical analysis were conducted to examine the associated factors on loss to follow-up., Results: A total of 3196 eligible MSM were enrolled at the baseline study. During one year of follow-up, 894 (28.0%) of them dropped out thoroughly while 2302 (72.1%) showed up at least on one visit. Factors as MSM who were at age 25 or younger, resided locally less than 1 year, being unemployed, self-recognized as heterosexuality or bisexuality, never taking HIV testing in the past year, having had sex with women in the past 6 months etc., were more likely to withdraw from the follow-up visits. Conclusion Age, length of residency, sex orientation and history of HIV testing were associated with the loss of follow-up among MSM cohort in our study. These factors should be considered in this kind of study design in the future.

Objective: To evaluate the long-term effectiveness of the first set 8 methadone maintenance treatment (MMT) clinics in China., Methods: Repeated cross-sectional surveys were conducted on the first month after the enrollment and 5 years later, among drug users who received MMT, using a standard questionnaire. Data on demographic characteristics, HIV-related high-risk behaviors, criminal records associated with drug use and related family/social functions were collected and analyzed., Results: There were 252 and 195 participants being interviewed at the baseline and the 5-year surveys, respectively. Of them, 66 participants were involved in both surveys. There was no significant differences on factors as ethnicity, level of education, working status, marital status and living status (P > 0.05) between the baseline and the 5-year surveys. Compared with data from the baseline survey, participants' behavior on drug abuse (100.0% vs. 24.1%, P < 0.001), needle sharing behavior (19.4% vs. 0.0%, P < 0.001), and exchanging sex for drugs (34.5% vs. 0.0%, P < 0.001) had significant decreases at the 5-year survey. Rates on condom use (10.6% vs. 25.0%, P = 0.004), and having jobs (27.8% vs. 47.7%, P < 0.001) had been improved significantly, while self-reported criminal cases related to drug use (15.1% vs. 1.5%, P < 0.001) and the contacts with drug users (88.9% vs. 31.3%, P < 0.001) had been significantly reduced after joining the MMT program., Conclusion: MMT could play an active role in reducing the HIV-related high-risk behaviors, criminal cases associated with drug abuse as well as enhancing the family and social functions of the MMT patients. Providing high quality service to the MMT clinic and trying to keep the drug users stick to the program remain difficult. It was also important to improve the training programs for staff working at the MMT clinics.

Maize (Zea mays L.) leaf is the main organ for photosynthesis. The area of leaves (especially the ear-leaf and the two leaves above and below the ear-leaf) plays a vital role in dry matter accumulation and grain yield. Therefore, genetic information on leaf area has a theoretical significance for breeding maize with high yield. In this study, a genetic linkage map composing of 184 simple sequence repeat (SSR) markers was constructed based on an F8 recombinant inbred line (RIL) population, which was derived from a cross between 478 and W312. The parents showed a significant difference in leaf area. The map covers 2084.1 cM with an average interval of 11.3 cM. QTLs for leaf area were identified under two-year's field experiments. Totally 7 QTLs were detected in two years, among which 4 QTLs were detected in 2006 and 3 QTLs in 2007. A major QTL on chromosome 2 (between umc1542 and umc1518) were detected in both 2006 and 2007. It explains 12.5% and 17.3% of the phenotypic variation, respectively. This locus can be used as a potental marker for improving maize leaf growth through marker assisted selection (MAS) approach.

Objective: To evaluate the effectiveness of the first eight pilot methadone maintenance treatment (MMT) clinics in China., Methods: A questionnaire survey of the clients at the 8 pilot MMT clinics was performed at entry, 6 month and 12 month follow-up. Drug using behaviors, drug related crime behaviors, and relationships in families were compared among at entry, 6 and 12 months follow-up., Results: There were 585, 609 and 468 clients involved at baseline, 6 month and 12 month follow-up surveys, respectively. At entry, 6 month and 12 month follow-up, the proportion of clients whose injection of drugs reduced from 69.1% to 8.9% and 8.8%, and the frequency of injection in the past month had reduced from 90 times per month to 2 times per month. Employment rate increased from 22.9% to 43.2% and 40.6%, and self-reported criminal behaviors reduced from 20.7% to 3.6% and 3.8%. At 12 month follow-up, 65.8% of clients reported a healthy family relationship, increased from 46.8% at entry, 95.9% of clients reported that they were satisfied with the MMT service., Conclusion: Pilot MMT program reduced drug use, drug injecting behaviors, drug related criminal behaviors, and improved relationship with family members. Therefore, MMT clinic should be considered as a platform for providing comprehensive services to drug users.

Growth of lateral roots is regulated by both environmental factors and nitrate (NO(-)(3)) content of the plant. The mechanism involved is not clearly understood. Two maize (Zea mays L.) inbred lines (478 and Wu312) were used to study the effect of different nitrate supply on lateral root (LR) growth by a whole plants agar culture. The results showed that increasing NO(-)(3)concentration in nutrient solution from 0.01 to 1.0 mmol/L significantly increased the LR length and root biomass. Lateral root density changed little with NO(-)(3) increase up to 5x10(-3) mol/L (for Wu312) - 10x10(-3) mol/L (for 478), then decreased significantly with increasing NO(-)(3). The inhibitory effect of high NO(-)(3) on root growth was weaker in 478 than in Wu312. The growth of lateral roots in Wu312 was completely inhibited by NO(-)(3) at a concentration of 10x10(-3) mol/L, whereas LR density of 478 could reach 30% (axial) and 50% (radicle) of its maximum even at NO(-)(3) 20x10(-3) mol/L. Both the shoot total N and shoot nitrate content increased with increasing NO(-)(3) level. They had similar mathematic functions with shoot/root ratio (Exponential Decay), LR density (Gaussian) and LR length (Parabola). When shoot N content exceed about 1.6 mol/kg and NO(-)(3) content exceed 0.22 mol/kg, shoot/root ratio increased rapidly; when the shoot N content exceed about 1.5 and NO(-)(3) exceed 0.16 mol/kg, LR densities began to decrease; when shoot N content reached about 1 mol/kg and NO(-)(3) content reached 0.10 mol/kg, the LR lengths began to decrease. The possible relationship between shoot NO(-)(3) content and lateral root growth was discussed.

A putative high-affinity phosphate (Pi) transporter gene in rice (Oryza sativa), OsLPT1, was isolated by RT-PCR from the leaves of the plants. The 1635-bp nucleotide sequence of OsLPT1 spans an open reading frame encoding a polypeptide of 535 amino acids with sequence similarity to phosphate transporters from other plant species. Southern blot analysis showed that the OsLPT1 gene might be present in three transcripts in the rice genome. RT-PCR analysis demonstrated the expression of OsLPT1 in both leaves and roots. The expression of OsLPT1 in the roots was enhanced by Pi deprivation. In situ hybridization revealed OsLPT1 expression in mesophyll cells, xylem parenchyma and phloem cells in the leaves, and in the epidermis, exodermis, and in the vasculature surrounding metaxylem vessels in the roots. The data suggests that the OsLPT1 protein may be involved in enhancing phosphate uptake under conditions of Pi starvation, and in the translocation of Pi among cells in shoots to increase the efficiency of internal Pi use.