In search of the “best” growth inhibitor

In searching for the “best” growth inhibitor, we decided to consider growth inhibition in terms of the lengths of the terminal sprouts. For it is logical to infer that the trees with the longer sprouts (after a 20-month period) will most likely be the ones that will need trimming in the future. Additionally, we reasoned that if a particular treatment produced a smaller proportion of “long” sprouts, then it would be a more effective growth inhibitor. It was now necessary to define what was meant by “long”. After consultation with foresters we chose cutoff lengths of 15.0, 25.0 and 35.0 cm. Hence the response variable was chosen to be the proportion of the terminal sprouts on a tree that exceeded a specified cutoff length. By varying the cutoff lengths, we would minimize the effect of the arbitrariness involved in choosing one particular length.     

Socioeconomic indexes and the new 1980 census occupational classification scheme

Because of their usefulness in a wide variety of research, socioeconomic scores have been revised several times to incorporate changes in the relevant components of the occupational structure and to conform with the changing census occupational classification schemes. The major purpose of this paper is to provide socioeconomic scores for the 1980 census occupational classification scheme. First, however, we review earlier versions of the socioeconomic index (SEI), summarize the relevant disparities between the 1970 and 1980 census occupational classificatory schemes, and then explain in detail the procedures used to reconcile the SEI with 1980 occupational codes. We also show that, although the 1980 occupational classificatory scheme differs radically from the 1970 occupational scheme, the socioconomic scores for 1980 occupational data replicate features found in 1970 data.     

A Study of the Development of Alcohol Use Disorder in Muslim Immigrant Workers in Korea

Abstract

This study examines the process by which Muslim immigrant workers, prohibited by their religion from drinking, develop alcohol use disorder when working in Korea. Participants were seven male immigrant workers who have lived in Korea for 6–10?years and all experienced a change in immigrant status, shifting from registered to unregistered. Utilizing grounded theory devised by Strauss and Corbin, 87 concepts, 24 subcategories, and 10 categories were derived as a result. By converting these categories into a paradigm model, participants moved through stages of “self-monitoring,” “confusion,” “self-despair,” and “daily collapse” as they developed alcohol use disorder, and began to take on an existence as drifters, not settling into life in Korea. Their “learning experiences of drinking to survive turning into experiences of causing social death” is considered a core category. The study’s results suggest that a rehabilitation program for immigrant workers needs to be developed wherein the program not only enables them to reflect on their current existence but also allows them to develop specific coping skills. Future research should be broadened to consider social support mechanisms and viewpoints of other people, including female immigrant workers, and local community members in close contact with Muslim immigrant workers.     

A missing link: psychological ownership as a mediator between transformational leadership and organizational citizenship behaviour

Interest in psychological ownership (PO) has increased due to its influence on employees’ attitudes and behaviours. This study focuses on PO as a mediator between transformational leadership (TL) and organizational citizenship behaviour (OCB) in the Korean public sector, which does not have employee stock ownership plans (ESOPs). With a total of 214 cases from the Korean public sector, structural equation modelling (SEM) analysis was conducted, and chi-square difference-based model comparison was performed to examine the mediating effect. Results indicated statistically significant relationships between TL and employees’ PO and between employees’ PO and their OCB. A statistically significant full mediating role of PO between TL and OCB in the Korean public sector context was found.     

Landscape of human resource development research in Korea: results from author co-citation network analysis

The present study examined major trends and issues of Human Resource Development (HRD) research in Korean context applying the author co-citation analysis (ACA) to three primary HRD-related journals in South Korea. Following the analyses of author co-citation frequency, correlation matrix, dendrogram, and the multi-dimensional scaling (MDS) map, the results were found as follows: (1) co-citation network identified seven topical clusters (i.e., human competency improvement for young men and e-learning designers, system approach for training effectiveness, competency for executives and HRD-ers, HRD evaluations, HRD solutions, mentoring in career development, leadership, and the role of professionals), (2) competency appeared as a keyword in multiple clusters, (3) unlike HRD in North America or Europe, learning (informal, organizational, self-directed, and lifelong learning) with a variety of HRD solutions comprised the dominant research stream, and (4) research activities for critical issues, such as diversity, development of workforce minority, and international HRD were largely missing.     

A Comparative Study of Child Abuse Risk Assessment in the United States and Korea

The perceptions and judgments of social workers who interview the child and family are especially significant factors in child abuse assessment process. The current study describes and compares child protection workers’ assessment processes in Korea and the USA through the use of case vignettes and in‐depth interview. The responses from social workers in these two countries were compared and discussed in the areas of: risk assessment; perception of the main problems; tolerance of corporal punishment; and judgments about appropriateness of interventions. Most revealing was that Korean social workers determined abuse based on their child abuse definition and the US Army FAP social workers determined abuse based on their definition, which was affected by legal standards and cultural differences. Korean social workers are more likely to remove a child from the home, even in mild cases, but US FAP social workers would recommend child removal from the home as a last option. The social workers that participated in this survey play a vital role in the safety of children in child protective services. Both countries can benefit from sharing information to improve the child protection services delivered. Social workers' professional judgment leads to objective and consistent outcomes and are less likely to compromise child safety in the decision making process.     

Estimating LAD Regression Coefficients with Best Subset Points

We propose a simple algorithm for estimating LAD (least-sum of absolute deviations) regression coefficients. The algorithm finds the best subset points to use to obtain the global optimizer in the series of a backtracking process by narrowing down the search space. Hence, the computational complexity reduces to a practical level. To evaluate the performance of the algorithm for LAD regression, we conducted simulation studies. The results showed that the algorithm is very competitive in terms of computation times required to get the same or similar results in comparison with other methods even when heavy censoring is given. Moreover, because the algorithm is quite simple and easy to understand, it can be implemented easily for various objective functions that are the variations of LAD.     

Sexual Debut and Mental Health Among South Korean Adolescents

Numerous studies have demonstrated the negative influence of sexual debut during adolescence on mental health outcomes. This article contributes to this literature by investigating whether sexual debut has negative effects on mental health among South Korean adolescents and whether the timing of adolescent sexual debut matters. Drawing on longitudinal data from a nationally representative survey, we first predicted mental health outcomes at one year after high school graduation using first sexual intercourse that had occurred before the outcomes were measured. In a second statistical model, adolescent sexual debut was defined as first coitus that had occurred before high school graduation. Sexual debut was associated with an increase in problematic aggressive behaviors for both genders. In contrast, only girls experienced a rise in depressive symptoms after becoming sexually active. For girls, having sex before high school graduation was correlated with worse mental health outcomes to the extent that sexual debut even enhanced the risk of suicidal ideation. We concluded that the negative effects of sexual activity among South Korean adolescents are attributable mainly to the sexually conservative atmosphere and gendered sexuality in that country.     

Analytical binomial lookback options with double-exponential jumps

We study the problem of the convergence of the adjusted binomial lookback option in double-exponential jump diffusion models. By using the results of [Dai, M., (2000). A modified binomial tree method for currency lookback options. Acta Mathematica Sinica, 16, 445–454; Kou, S., & Wang, H. (2004). Option pricing under a double exponential jump diffusion model. Management Science, 50, 1178–1192] and [Park, H.S., Kim, K.I., & Qian, X. (2009). A Mathematical modeling for the Lookback option with jump diffusion using Binomial tree method. Journal of Computational and Applied Mathematics, preprint], we show the equivalence between the adjusted binomial tree method and the explicit difference scheme. The convergence is also theoretically proved through the notion of viscosity solution. Numerical results coincide with the theoretical results.     

Daily use of sildenafil 50mg at night effectively ameliorates nocturia in patients with lower urinary tract symptoms associated with benign prostatic hyperplasia: an exploratory multicenter,double-blind,randomized, placebo-controlled study

Purpose: To compare the efficacy and safety of sildenafil 25?mg qd, 25?mg bid or 50?mg qd – on treating lower urinary tract symptoms with benign prostatic hyperplasia (LUTS/BPH).

Materials and methods: Men aged?>?45 years with LUTS/BPH were randomly assigned to receive sildenafil 25?mg qd (n?=?42), bid (n?=?41), 50?mg qd (n?=?38) or placebo (n?=?41) for 8 weeks. Changes from baseline in International Prostate Symptom Score (I-PSS), maximum urinary flow rate (Qmax) and postvoid residual urine volume (PVR) were assessed at week 4 and week 8.

Results: Sildenafil 25?mg qd (-7.3?±?5.8) and 25?mg bid (-7.0?±?5.7) exhibited significant improvements of I-PSS compared to placebo (-5.2?±?6.4) (p?=?0.020, 0.025, respectively). In particular, voiding domain was more affected than storage domain. Only sildenafil 50?mg qd improved nocturia significantly (versus placebo, p?=?0.027). Quality of life score was improved in all treatment groups. Q_max and PVR did not change significantly in all groups. All regimens were well tolerated.

Conclusions: Sildenafil 25?mg qd, 25?mg bid and 50?mg qd are safe and effective to improve LUTS/BPH in long term, along with coexisting ED. In particular, nocturia is most well-controlled by 50?mg qd.