25 research outputs found

    Influences of mentoring functions on job satisfaction and organizational commitment of graduate employees

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    Abstract: A significant percentage of the workforce, within the construction sector is nearing retirement age over the next ten years. These employees have acquired a tremendous amount of knowledge about how things work, how to get things done and who to go to when problems arise. Losing their expertise and experience could significantly reduce efficiency, resulting in costly mistakes, unexpected quality problems, or significant disruptions in services and or performance. The business world has long known and relied upon mentoring as a proven technique for developing in house talent. Previous studies proved that the implementation of mentoring programme is beneficial for enhancing employee skills and attitudes. Few researchers are devoted to exploring the impact. This paper is aimed at examining the effects of mentoring functions on the job satisfaction and organizational commitment of new graduates in the South African construction industry..

    Combining Phylogeography with Distribution Modeling: Multiple Pleistocene Range Expansions in a Parthenogenetic Gecko from the Australian Arid Zone

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    Phylogenetic and geographic evidence suggest that many parthenogenetic organisms have evolved recently and have spread rapidly. These patterns play a critical role in our understanding of the relative merits of sexual versus asexual reproductive modes, yet their interpretation is often hampered by a lack of detail. Here we present a detailed phylogeographic study of a vertebrate parthenogen, the Australian gecko Heteronotia binoei, in combination with statistical and biophysical modeling of its distribution during the last glacial maximum. Parthenogenetic H. binoei occur in the Australian arid zone and have the widest range of any known vertebrate parthenogen. They are broadly sympatric with their sexual counterparts, from which they arose via hybridization. We have applied nested clade phylogeographic, effective migration, and mismatch distribution analyses to mitochondrial DNA (mtDNA) sequences obtained for 319 individuals sampled throughout the known geographic ranges of two parthenogenetic mitochondrial lineages. These analyses provide strong evidence for past range expansion events from west to east across the arid zone, and for continuing eastward range expansion. Parthenogen formation and range expansion events date to the late Pleistocene, with one lineage expanding from the northwest of its present range around 240,000 years ago and the second lineage expanding from the far west around 70,000 years ago. Statistical and biophysical distribution models support these inferences of recent range expansion, with suitable climatic conditions during the last glacial maximum most likely limited to parts of the arid zone north and west of much of the current ranges of these lineages. Combination of phylogeographic analyses and distribution modeling allowed considerably stronger inferences of the history of this complex than either would in isolation, illustrating the power of combining complementary analytical approaches

    Diploids in the Cryptococcus neoformans Serotype A Population Homozygous for the Ξ± Mating Type Originate via Unisexual Mating

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    The ubiquitous environmental human pathogen Cryptococcus neoformans is traditionally considered a haploid fungus with a bipolar mating system. In nature, the α mating type is overwhelmingly predominant over a. How genetic diversity is generated and maintained by this heterothallic fungus in a largely unisexual α population is unclear. Recently it was discovered that C. neoformans can undergo same-sex mating under laboratory conditions generating both diploid intermediates and haploid recombinant progeny. Same-sex mating (α-α) also occurs in nature as evidenced by the existence of natural diploid αADα hybrids that arose by fusion between two α cells of different serotypes (A and D). How significantly this novel sexual style contributes to genetic diversity of the Cryptococcus population was unknown. In this study, ∼500 natural C. neoformans isolates were tested for ploidy and close to 8% were found to be diploid by fluorescence flow cytometry analysis. The majority of these diploids were serotype A isolates with two copies of the α MAT locus allele. Among those, several are intra-varietal allodiploid hybrids produced by fusion of two genetically distinct α cells through same-sex mating. The majority, however, are autodiploids that harbor two seemingly identical copies of the genome and arose via either endoreplication or clonal mating. The diploids identified were isolated from different geographic locations and varied genotypically and phenotypically, indicating independent non-clonal origins. The present study demonstrates that unisexual mating produces diploid isolates of C. neoformans in nature, giving rise to populations of hybrids and mixed ploidy. Our findings underscore the importance of same-sex mating in shaping the current population structure of this important human pathogenic fungus, with implications for mechanisms of selfing and inbreeding in other microbial pathogens

    Mate choice drives evolutionary stability in a hybrid complex

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    Previous studies have shown that assortative mating acts as a driver of speciation by countering hybridization between two populations of the same species (pre-zygotic isolation) or through mate choice among the hybrids (hybrid speciation). In both speciation types, assortative mating promotes speciation over a transient hybridization stage. We studied mate choice in a hybrid vertebrate complex, the allopolyploid fish Squalius alburnoides. This complex is composed by several genomotypes connected by an intricate reproductive dynamics. We developed a model that predicts the hybrid complex can persist when females exhibit particular mate choice patterns. Our model is able to reproduce the diversity of population dynamic outcomes found in nature, namely the dominance of the triploids and the dominance of the tetraploids, depending on female mate choice patterns and frequency of the parental species. Experimental mate choice trials showed that females exhibit the preferences predicted by the model. Thus, despite the known role of assortative mating in driving speciation, our findings suggest that certain mate choice patterns can instead hinder speciation and support the persistence of hybrids over time without speciation or extinction

    The Courage to See the Sights of the Tenement

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    Residential Smoking Therapy

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    OBJECTIVE: To evaluate a pilot 4-day residential smoking treatment program for smokers who had relapsed after participation in an outpatient smoking program. DESIGN: A single-arm clinical trial. Participants stayed in a supportive, smoke-free environment for 4 days during which they attended educational sessions on nutrition, exercise, and psychology. Nicotine withdrawal was treated with nicotine inhalers and patches. After discharge, participants attended monthly outpatient group sessions for 6 months. SETTING: The Durham, NC Veterans Affairs Medical Center residential unit. PARTICIPANTS: Twenty-three medical outpatient smokers. MEASUREMENTS: Seven-day point prevalence smoking abstinence was determined by self-report of zero cigarettes smoked and verified by exhaled carbon monoxide <8 parts per million. MAIN RESULTS: Participants' mean age was 57.4 years; 100% were male; 61% were Caucasian; and 39% were African American. The mean score on the FagerstrΓΆm Test for Nicotine Dependence was 7.1 (SD 2.3). Daily nicotine doses ranged from the nicotine inhaler alone to 56 mg of transdermal nicotine plus nicotine inhaler. Verified smoking abstinence on discharge (after 4 days) was 21/23 or 91.3% (95% confidence interval [95% CI], 73 to 100). At 6 months, the 7-day point abstinence rate was 6/23 or 26.1% (95% CI, 15 to 36). CONCLUSIONS: This pilot residential smoking treatment program was designed to assist smokers who relapsed after outpatient treatment. Four days of residential smoking therapy successfully relieved smoking withdrawal. At 6 months after discharge, participants maintained an abstinence rate comparable to other medical therapies for smoking

    Degenerative spondylolisthesis does not influence surgical results of laminoplasty in elderly cervical spondylotic myelopathy patients

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    The objective of the study was to investigate the comorbidity of degenerative spondylolisthesis (DS), in elderly cervical spondylotic myelopathy (CSM) patients in our hospital, and the correlation between surgical results and preoperative DS. There are few studies on the outcome of laminoplasty for CSM with DS. A total of 49 elderly patients (>65Β years old) who eventually had surgical treatment for CSM were evaluated. A slippage displacement of more than 2.5Β mm at least at one level was classified to have a positive DS on flexion/extension radiographs (DS group). A slippage displacement less than 1.0Β mm was considered a negative DS (non-DS group). Seventeen patients who had slippage of 1.0–2.5Β mm were excluded from the study. The DS group (nΒ =Β 15) included cases with DS at preoperation, while the remaining cases (nΒ =Β 17) belonged to the non-DS group. The flexion/extension radiographs of the two groups were compared for range of motion and clinical results at 3Β years after the operation. Of all elderly patients, 30.6% had DS. There was no significant difference between the two groups based on the clinical results. The range of motion of all cervical spines (DS group and non-DS group) was significantly limited. However, there was no significant difference between the two groups. New postoperative DS appeared in four patients, of which two were from the DS group and two from the non-DS group. These data suggest that degenerative spondylolisthesis does not influence surgical results in elderly cervical spondylotic myelopathy patients
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