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531.
  1. Alpine treelines are expected to shift upward due to recent climate change. However, interpretation of changes in montane systems has been problematic because effects of climate change are frequently confounded with those of land use changes. The eastern Himalaya, particularly Langtang National Park, Central Nepal, has been relatively undisturbed for centuries and thus presents an opportunity for studying climate change impacts on alpine treeline uncontaminated by potential confounding factors.
  2. We studied two dominant species, Abies spectabilis (AS) and Rhododendron campanulatum (RC), above and below the treeline on two mountains. We constructed 13 transects, each spanning up to 400 m in elevation, in which we recorded height and state (dead or alive) of all trees, as well as slope, aspect, canopy density, and measures of anthropogenic and animal disturbance.
  3. All size classes of RC plants had lower mortality above treeline than below it, and young RC plants (<2 m tall) were at higher density above treeline than below. AS shows little evidence of a position change from the historic treeline, with a sudden extreme drop in density above treeline compared to below. Recruitment, as measured by size–class distribution, was greater above treeline than below for both species but AS is confined to ~25 m above treeline whereas RC is luxuriantly growing up to 200 m above treeline.
  4. Synthesis. Evidence suggests that the elevational limits of RC have shifted upward both because (a) young plants above treeline benefited from facilitation of recruitment by surrounding vegetation, allowing upward expansion of recruitment, and (b) temperature amelioration to mature plants increased adult survival. We predict that the current pure stand of RC growing above treeline will be colonized by AS that will, in turn, outshade and eventually relegate RC to be a minor component of the community, as is the current situation below the treeline.
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532.
Changes in species composition and richness across the sub-alpine forest ecotone are well known phenomena. The total number of species at a regional scale drops substantially above the forest-line in the central Himalayas of Nepal. This study tests the effect of a forest border ecotone on a local scale using a grain size of 100 m2. We sampled a set of vertical transects across a sloping sub-alpine forest line where canopy and temperature covary, and a set of horizontal transects across a forest ecotone where there was no altitudinal difference to eliminate the influence of temperature. Detrended correspondence analysis revealed a continuous change in species composition across the forest border ecotone. Species turnover was, in general, low, and species richness did not vary very much between the forest and open landscapes. We attribute this to the grazing and browsing pressure in the area, which may have lowered the tree line. A reduced tree line compared to the climatic limit may facilitate enhanced species richness above the forest line. There was no significant difference in species richness between forest and open landscapes along horizontal transects where temperature variations were minimized. This study exemplifies the difficulties encountered on a local scale when one aims to test diversity hypotheses deduced from general models on forest-ecotone effect and mass effect. The low species turnover and minor differences in alpha diversity may be because the area is a cultural landscape and the homogenizing effect of domestic animals overrides some of the edge effects of the ecotone.  相似文献   
533.
Two molecular identification techniques for differentiating six lepidopteran pests infesting apples in Korea are presented. These six species include two internal fruit feeders (Grapholita molesta and Carposina sasakii), two leaf rollers (Adoxophyes sp. and Archips breviplicanus) and two leaf miners (Phyllonorycter ringoniella and Lyonetia prunifoliella). All species occur until near harvest and reduce apple production. A 489 bp fragment of mitochondrial cytochrome oxidase subunit I (COI) was sequenced in these six species. The sequence was used to select species-specific restriction enzyme sites and to design diagnostic polymerase chain reaction (PCR) primers, resulting in the development of restriction fragment length polymorphism (RFLP)-PCR and diagnostic PCR. These methods were reliable and rapid in the identification of these six species.  相似文献   
534.
535.
ABSTRACT

The endoplasmic reticulum (ER) is the largest membrane-bound organelle in eukaryotic cells and plays critical roles in diverse processes in metabolism, signaling and intracellular organization. In response to stress stimuli such as nutrient deprivation, accumulation of misfolded proteins or exposure to chemicals, the ER increases in size through upregulated synthesis of its components to counteract the stress. To restore physiological size, the excess ER components are continuously dismantled and degraded by reticulophagy, a form of autophagy that targets, via adaptor molecules called reticulophagy receptors, specific ER portions to the lysosome for degradation. Previous studies have identified several ER resident proteins as reticulophagy receptors. In a recent study, we identified CALCOCO1 as a soluble reticulophagy receptor for the degradation of tubular ER in response to proteotoxic and starvation-induced stress. On the ER membrane, CALCOCO1 interacts with VAPA and VAPB via a FFAT-like motif and recruits autophagy machinery by binding directly to Atg8-family proteins via LIR and UDS interacting region (UIR) motifs acting co-dependently. Depletion of CALCOCO1 in cultured cells led to an impaired ER degradation during stress.  相似文献   
536.
Establishment of growth factor-dependent MOPC 104E cell line in vitro   总被引:1,自引:0,他引:1  
The MOPC 104E cell line has been adapted to grow in vitro using a combination of feeder layer and growth factor(s). The growth of this myeloma cell line is dependent on the presence of growth factor(s). Growth-promoting activity generated from T-cell-mitogen-stimulated, Corynebacterium parvum-stimulated spleen cell culture supernatant, and peritoneal adherent cell culture supernatants gives dose-dependent proliferation. Generation of growth factors in the serum-free bovine serum albumin-substituted media and a rapid assay system based on [3H]thymidine uptake for the quantitation of growth promoting activity are described.  相似文献   
537.
A method of assessing body condition of Asian elephants (Elephas maximus) is presented. The method uses visual assessment to assign numerical scores to six different regions of the body, which are totaled to give a numerical index ranging from 0–11. The relationship between the index and morphometric variables is compared for a sample of 119 juvenile and young adult elephants from southern India, Nepal, and Myanmar. Mean ages of males and females were similar. Mean index of body condition (with standard error [SE]) was 7.3±0.2 points. No significant correlation was found between index of body condition and age over both sexes (r=0.01, n=50). Results were equivalent when sexes were treated separately (females: r=0.03, n=24; males: r=0.01, n=26). Sexes did not differ in height of the shoulder or body condition in our sample, but there was significant sexual dimorphism in breadth of the zygomatic arch and three measures of subcutaneous fat: girth of neck, thickness of cervical fold, and thickness of anal flap. These three measures were also significantly correlated with each other. Our assessment method should prove a practical tool for ecologic studies, but the relationship of the index to percentage of body fat should be determined using heavy water dilution methodology. Zoo Biol 25:187–200, 2006. © 2006 Wiley‐Liss, Inc.  相似文献   
538.
During five years of birth season fieldwork, we observed two births and three peri-birth instances of behavior of free-ranging rhesus living in Kathmandu, Nepal. These constitute the first two recorded free-ranging rhesus births, and we compare them to the behavior which has been observed in captivity and expected in the wild. The free-ranging parturition behavior was characterized by a general lack of contact with other troop members and by overall inconspicuousness. In the first birth we observed, the troop moved about 70 m up the hill, leaving the laboring female behind on an open hillside. Two males, a female and a juvenile returned and rested about 20 m from the delivering female. During the second delivery, the female stayed with the troop and seemed to participate normally in most troop interactions, although she avoided physical contact with other troop members. We propose that this near-normal behavior may help to assure successful parturition by allowing the female the needed social isolation and inconspicuousness without any loss of troop protection. It may also partly explain why births have not been observed during previous studies. Observations of rhesus parturition behavior reported from studies of captive monkeys and reports from other free-ranging primate studies are compared with our data.  相似文献   
539.
Rare fishes of Himalayan waters of Nepal   总被引:1,自引:0,他引:1  
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540.
BackgroundGlobally, 235 million people are impacted by humanitarian emergencies worldwide, presenting increased risk of experiencing a mental disorder. Our objective was to test the effectiveness of a brief group psychological treatment delivered by trained facilitators without prior professional mental health training in a disaster-prone setting.Methods and findingsWe conducted a cluster randomized controlled trial (cRCT) from November 25, 2018 through September 30, 2019. Participants in both arms were assessed at baseline, midline (7 weeks post-baseline, which was approximately 1 week after treatment in the experimental arm), and endline (20 weeks post-baseline, which was approximately 3 months posttreatment). The intervention was Group Problem Management Plus (PM+), a psychological treatment of 5 weekly sessions, which was compared with enhanced usual care (EUC) consisting of a family psychoeducation meeting with a referral option to primary care providers trained in mental healthcare. The setting was 72 wards (geographic unit of clustering) in eastern Nepal, with 1 PM+ group per ward in the treatment arm. Wards were eligible if they were in disaster-prone regions and residents spoke Nepali. Wards were assigned to study arms based on covariate constrained randomization. Eligible participants were adult women and men 18 years of age and older who met screening criteria for psychological distress and functional impairment. Outcomes were measured at the participant level, with assessors blinded to group assignment. The primary outcome was psychological distress assessed with the General Health Questionnaire (GHQ-12). Secondary outcomes included depression symptoms, posttraumatic stress disorder (PTSD) symptoms, “heart–mind” problems, social support, somatic symptoms, and functional impairment. The hypothesized mediator was skill use aligned with the treatment’s mechanisms of action. A total of 324 participants were enrolled in the control arm (36 wards) and 319 in the Group PM+ arm (36 wards). The overall sample (N = 611) had a median age of 45 years (range 18–91 years), 82% of participants were female, 50% had recently experienced a natural disaster, and 31% had a chronic physical illness. Endline assessments were completed by 302 participants in the control arm (36 wards) and 303 participants in the Group PM+ arm (36 wards). At the midline assessment (immediately after Group PM+ in the experimental arm), mean GHQ-12 total score was 2.7 units lower in Group PM+ compared to control (95% CI: 1.7, 3.7, p < 0.001), with standardized mean difference (SMD) of −0.4 (95% CI: −0.5, −0.2). At 3 months posttreatment (primary endpoint), mean GHQ-12 total score was 1.4 units lower in Group PM+ compared to control (95% CI: 0.3, 2.5, p = 0.014), with SMD of −0.2 (95% CI: −0.4, 0.0). Among the secondary outcomes, Group PM+ was associated with endline with a larger proportion attaining more than 50% reduction in depression symptoms (29.9% of Group PM+ arm versus 17.3% of control arm, risk ratio = 1.7, 95% CI: 1.2, 2.4, p = 0.002). Fewer participants in the Group PM+ arm continued to have “heart–mind” problems at endline (58.8%) compared to the control arm (69.4%), risk ratio = 0.8 (95% CI, 0.7, 1.0, p = 0.042). Group PM+ was not associated with lower PTSD symptoms or functional impairment. Use of psychosocial skills at midline was estimated to explain 31% of the PM+ effect on endline GHQ-12 scores. Adverse events in the control arm included 1 suicide death and 1 reportable incidence of domestic violence; in the Group PM+ arm, there was 1 death due to physical illness. Study limitations include lack of power to evaluate gender-specific effects, lack of long-term outcomes (e.g., 12 months posttreatment), and lack of cost-effectiveness information.ConclusionsIn this study, we found that a 5-session group psychological treatment delivered by nonspecialists modestly reduced psychological distress and depression symptoms in a setting prone to humanitarian emergencies. Benefits were partly explained by the degree of psychosocial skill use in daily life. To improve the treatment benefit, future implementation should focus on approaches to enhance skill use by PM+ participants.Trial registrationClinicalTrials.gov NCT03747055.

Mark Jordans and co-workers evaluate a group therapy intervention in adults affected by psychological distress in Nepal.  相似文献   
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