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Charge carrier scattering at grain boundaries (GBs) in a chemical vapor deposition (CVD) graphene reduces the carrier mobility and degrades the performance of the graphene device, which is expected to affect the quantum Hall effect (QHE). This study investigated the influence of individual GBs on the QH state at different stitching angles of the GB in a monolayer CVD graphene. The measured voltage probes of the equipotential line in the QH state showed that the longitudinal resistance (Rxx) was affected by the scattering of the GB only in the low carrier concentration region, and the standard QHE of a monolayer graphene was observed regardless of the stitching angle of the GB. In addition, a controlled device with an added metal bar placed in the middle of the Hall bar configuration was introduced. Despite the fact that the equipotential lines in the controlled device were broken by the additional metal bar, only the Rxx was affected by nonzero resistance, whereas the Hall resistance (Rxy) revealed the well-quantized plateaus in the QH state. Thus, our study clarifies the effect of individual GBs on the QH states of graphenes.  相似文献   
103.
Lactococcus lactis strain Plasma (LC-Plasma) is reported to have anti-viral effects via direct activation of plasmacytoid dendritic cells, which upregulate the production of type I and III interferons. A randomized, placebo-controlled, double-blind, parallel group study was designed for elementary schoolchildren, grades 1 to 3, in Vietnam. LC-Plasma or a control were administered to schoolchildren as a beverage (1.0 × 1011 count LC-Plasma/day/person). The primary endpoint was to determine the efficacy of LC-Plasma in reducing the cumulative days absent from school due to upper respiratory disease (URID) and gastrointestinal disease (GID), and the secondary endpoint was to evaluate the potency of LC-Plasma on URID/GID symptoms and general well-being scores. LC-Plasma intake significantly reduced the cumulative days absent from school due to URID/GID (Odds ratio (OR) = 0.57, p = 0.004) and URID alone (OR = 0.56, p = 0.005); LC-Plasma also significantly reduced the number of cumulative fever positive days during the first 4 weeks of intervention (OR = 0.58, p = 0.001) and cumulative days with diarrhea during the last 4 weeks of the intervention period (OR = 0.78, p = 0.01). The number of positive general wellbeing days was significantly improved in the LC-Plasma group compared with the control throughout the intervention period (OR = 0.93, 0.93, p = 0.03, 0.04 in the first and last 4 weeks of the intervention, respectively). These data suggest that LC-Plasma seems to improve the health condition of elementary schoolchildren and reduces school absenteeism due to infectious disease, especially URID.  相似文献   
104.
In an attempt to assess what adolescents think they would do if they knew of previous adolescent suicides, 116 high school students viewed a videotaped vignette of a distressed high school student and were asked to imagine that they were she. They were then given an information sheet summarizing the vignette. One third of the information sheets contained an embedded sentence that two friends had recently committed suicide, another third a sentence that two friends had recently died in an airplane crash, and one third contained no embedded sentence. Subjects were then asked to rate the likelihood that they would engage in various behavioral alternatives (commit suicide, run away, abuse alcohol, drive recklessly, seek psychological help, try harder at school, adapt to the situation) and the degree to which they blamed the various situational factors described in the vignette (school, friends, alcohol, parents). Subjects also completed the Reasons fGr Living Inventory (RFL). The only significant difference across groups was the significantly higher score of the suicide group on the fear of social disapproval scale of the RFL. Adolescents may not be influenced by news about suicide or they may just deny such influence.  相似文献   
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M Ip  P Y Chau  S Y So  W K Lam 《Tubercle》1989,70(4):281-285
We review the results of bronchial aspirate culture for mycobacteria sent routinely in a series of 1734 fibreoptic bronchoscopic procedures. The incidence of tuberculosis in the series was 8.3% (144 cases). Of these cases, a positive bronchial aspirate culture was obtained in 119 (82.6%) cases, and it was the exclusive means of diagnosis in 64 (44.4%). In 66% of these cases tuberculosis was not suspected at the time of bronchoscopy. Our results suggest that in an area with a high prevalence of tuberculosis, routine bronchial aspirate culture is a useful adjunct to diagnosis.  相似文献   
109.
In the present study, the influences of diets (i.e. chow and AIN-93 diets) on the interpretation of various fecal parameters including viable microbiota, moisture, weight, and short-chain fatty acids in rats fed different amounts of inulin (0.5–2 g/kg). Eight groups of rats (n = 8/group) were fed, for 4 weeks, chow or AIN-93 diets with or without inulin supplementation. Fecal samples were analyzed for different fecal parameters. After a 2-week adaptation, apparent differences in some fecal parameters were observed between the chow and AIN-93 diet groups. Throughout the 4-week intervention period, significantly (p < 0.05) higher Lactobacillus spp. counts, fecal moisture (∼2.7-fold), and fecal weight (∼5.8-fold) were observed with chow diet over AIN-93 diet. More specifically, significant elevations in the levels of Bifidobacterium spp., Lactobacillus spp., fecal moisture, and fecal weight could be observed at low-dose (0.5 g/kg) of inulin in chow diet groups, while most of these changes could merely be seen at medium-dose (1 g/kg) in AIN-93 diet groups. These results demonstrated that the choice of experimental diets would affect the comparison of fecal parameters as well as the interpretation of effective dosage of prebiotic in intestinal health assessments.  相似文献   
110.
To assess whether people's reactions to family members of child suicide attemptors were similar to reactions to family members of (a) actual suicides and (b) actual suicides that were preceded by a failed suicide attempt, 120 shoppers (60 men and 60 women) read and responded to one of five short newspaper articles about an incident of a 10-year-old child who either (a) attempted suicide, (b) committed suicide, (c) committed suicide after a previous suicide attempt, (d) died accidentally, or (e) died of a viral illness. Opinions about the psychological health of the victim and reactions to the surviving family varied depending on the nature of the incident. However, in many instances reactions to families of suicide attemptors could not be differentiated from reactions to families of actual suicides. Therefore, it is likely that the number of people affected by negative community reactions to suicidal behavior has been previously underestimated.  相似文献   
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