283 research outputs found
Psychological Capital and Professional Identity: A Study of Professional Business Students
This research article reports the results and findings of an online survey questionnaire administered to 593 Masters of Business Administration (MBA) students using the MCPIS-9 and PCQ-12 instruments that measure Professional Identity (ProfId) and Psychological Capital (PsyCap), respectively. The results indicated a strong sense of ProfId (M = 4.2/5.0, SD = 0.66, N = 593), and a significant and positive relationship (p < .01, ΔR2adj = .25, N = 593) between PsyCap and ProfId. The results of this study represent a fruitful, albeit initial, foray into the ProfId and PsyCap of professional business students. The implications of these results inform and equip program stakeholders to devise curricular and pedagogical approaches to support students’ sense of self in their career trajectory
Efisiensi Alat Muat Dan Alat Angkut Untuk Pengupasan Overburden Pada Site a Di PT. Samantaka Batubara Desa Pauh Ranap Kecamatan Peranap Kabupaten Indragiri Hulu Provinsi Riau
Dalam USAha peningkatan produktifitas Overburden diperlukan rencana kebutuhan alat muat dan alat angkut yang tujuannya agar alat muat dan alat angkut yang dioperasikan mampu bekerja secara optimal sesuai dengan kondisi alat tersebut. Metode penambangan yang diterapkan di PT. Samantaka Batubara adalah cara tambang terbuka dengan penambangan konvensional yaitu dengan menggunakan kombinasi peralatan excavator dan dump truck. Menurut keputusan Bupati Indaragiri Hulu Nomor 001/IUP/545-02/II/2013 tentang persetujuan peningkatan izin USAha pertambangan eksplorasi menjadi izin USAha pertambangan operasi produksi kepada PT. Samantaka Batubara dengan luas wilayah IUP OP 19.040 Ha
Cascading effects of canopy mortality drive long-term changes in understorey diversity in temperate old-growth forests of Europe
Questions: We investigated the influence of protracted mortality of a dominant canopy tree (Abies alba) on long-term understorey dynamics. We ask (a) how tree regeneration and understorey species diversity and composition changed over 32 years; and (b) whether the observed changes were mainly driven by mortality of A. alba.
Location: Three old-growth forest reserves dominated by A. alba and Fagus sylvatica in the Dinaric Mountains of Slovenia.
Method: Tree layer and understorey regeneration and herbs were surveyed in 147 plots across the three forest reserves in 1983 and 2015. Soils were also sampled in 2015. The study period coincides with a protracted period of increased A. alba mortality in the canopy layer associated with anthropogenic emissions.
Results: Between 1983 and 2015, the decline in canopy layer A. alba caused a recruitment pulse of F. sylvatica regeneration to the subcanopy tree layer across the three reserves. These changes were accompanied by a significant decline in plot level herb species richness. A model-based analysis of beta-diversity revealed significant community convergence during the study period, mainly caused by the loss of rare species. Ellenberg values indicate that these changes were mainly driven by loss of understorey light, while an increase in soil pH may have played a role also.
Conclusions: This observational study suggests that the long-term decline of A. alba resulted in a cascade of processes - widespread F. sylvatica recruitment that impeded penetration of light to the forest floor, and possibly a change in soil conditions due to the decline of coniferous litter. These changes caused a significant loss of herb diversity and homogenization of the understorey community across the three sites. This study sheds light on the potential cascading consequences triggered by episodes of increased tree mortality resulting from global-change-type drivers
Inter-specific aggression generates ant mosaics in canopies of primary tropical rainforest
The ant mosaic is a concept of the non-random spatial distribution of individual ant species in trees built upon the assumption of interspecific behavioural associations. However, colony identity and environmental variance may also play a role in species distribution. Here we assess the presence of ant mosaics in a primary forest ecosystem and whether they are structured by species' aggressive behaviours or by habitat filtering.
We sampled arboreal ants from vertically stratified baits exposed in 225 canopy trees in a 9-ha plot of primary lowland forest in Papua New Guinea, the largest forest area surveyed to detect ant mosaics. We performed behavioural tests on conspecific ants from adjacent trees to determine the territories of individual colonies. We explored the environmental effects on the ant communities using information on the plot vegetation structure and topography. Furthermore, we created a novel statistical method to test for the community non-random spatial structure across the plot via spatial randomisation of individual colony territories. Finally, we linked spatial segregation among the four most common species to experimentally assessed rates of interspecies aggression.
The ant communities comprised 57 species of highly variable abundance and vertical stratification. Ant community composition was spatially dependent, but it was not affected by tree species composition or canopy connectivity. Only local elevation had a significant but rather small effect. Individual colony territories ranged from one tree to 0.7 ha. Species were significantly over-dispersed, with their territory overlap significantly reduced. The level of aggression between pairs of the four most common species was positively correlated with their spatial segregation. Our study demonstrates the presence of ant mosaics in tropical pristine forest, which are maintained by interspecific aggression rather than habitat filtering, with vegetation structure having a rather small and indirect effect, probably linked to microclimate variability.publishedVersio
Gastric cancer and Helicobacter pylori: a combined analysis of 12 case control studies nested within prospective cohorts
BACKGROUND: The magnitude of the association
between Helicobacter pylori and
incidence of gastric cancer is unclear. H
pylori infection and the circulating antibody
response can be lost with development
of cancer; thus retrospective studies
are subject to bias resulting from classifi-
cation of cases as H pylori negative when
they were infected in the past.
AIMS: To combine data from all case control
studies nested within prospective
cohorts to assess more reliably the relative
risk of gastric cancer associated with H
pylori infection.To investigate variation in
relative risk by age, sex, cancer type and
subsite, and interval between blood sampling
and cancer diagnosis.
METHODS: Studies were eligible if blood
samples for H pylori serology were collected
before diagnosis of gastric cancer in
cases. Identified published studies and two
unpublished studies were included. Individual
subject data were obtained for
each. Matched odds ratios (ORs) and 95%
confidence intervals (95% CI) were calculated
for the association between H pylori
and gastric cancer.
RESULTS: Twelve studies with 1228 gastric
cancer cases were considered. The association
with H pylori was restricted to noncardia
cancers (OR 3.0; 95% CI 2.3–3.8)
and was stronger when blood samples for
H pylori serology were collected 10+ years
before cancer diagnosis (5.9; 3.4–10.3). H
pylori infection was not associated with an
altered overall risk of cardia cancer (1.0;
0.7–1.4).
CONCLUSIONS: These results suggest that
5.9 is the best estimate of the relative risk
of non-cardia cancer associated with H
pylori infection and that H pylori does not
increase the risk of cardia cancer. They
also support the idea that when H pylori
status is assessed close to cancer diagnosis,
the magnitude of the non-cardia
association may be underestimated
First detection of NH3 (1,0 - 0,0) from a low mass cloud core: On the low ammonia abundance of the rho Oph A core
Odin has successfully observed the molecular core rho Oph A in the 572.5 GHz
rotational ground state line of ammonia, NH3 (J,K = 1,0 - 0,0). The
interpretation of this result makes use of complementary molecular line data
obtained from the ground (C17O and CH3OH) as part of the Odin preparatory work.
Comparison of these observations with theoretical model calculations of line
excitation and transfer yields a quite ordinary abundance of methanol, X(CH3OH)
= 3e-9. Unless NH3 is not entirely segregated from C17O and CH3OH, ammonia is
found to be significantly underabundant with respect to typical dense core
values, viz. X(NH3) = 8e-10.Comment: 4 pages, 2 figures, 2 tables, to appear in Astron. Astrophys. Letter
Совершенствование системы найма и адаптации персонала на предприятии
Объектом исследования является: торговая компания ООО "Симост". В рамках магистерской работы проводились исследования теоретических и методологических основ найма и адаптации персонала в компании. Был проведен анализ состава, структуры и движения персонала, изучена система найма и адаптации в компании "Симост". В результате исследования автором была предложена система мероприятий по совершенствованию процесса найма и адаптации персонала в компании "Симост".The object of the study is: the trading company "Simost". In the master's thesis, research was carried out on the theoretical and methodological foundations of hiring and adaptation of personnel in the company. An analysis was made of the composition, structure and movement of personnel, the hiring and adaptation system in the company "Simost" was studied. As a result of the research, the author proposed a system of measures to improve the process of recruitment and adaptation of personnel in the company "Simost"
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