The struggle of Batak Simalungun for their identity in Church organization in Simalungun,Medan, Indonesia

ABSTRACT

This research aims to find out the struggle of Batak Simalungun for their identity in church organization in Simalungun. This research uses a qualitative research approach, This qualitative research also uses an ethnographic approach. The qualitative research has at least five approaches and therefore can choose one of the five approaches. The results show about three demands of the Simalungun Batak movement over a special identity of Simalungun also include the church organization environment, where the entire Batak Church led by RMG touches on the original structures of Batak society and culture.     

An Agent‐Based Model for Pathogen Persistence and Cross‐Contamination Dynamics in a Food Facility

We used an agent‐based modeling (ABM) framework and developed a mathematical model to explain the complex dynamics of microbial persistence and spread within a food facility and to aid risk managers in identifying effective mitigation options. The model explicitly considered personal hygiene practices by food handlers as well as their activities and simulated a spatially explicit dynamic system representing complex interaction patterns among food handlers, facility environment, and foods. To demonstrate the utility of the model in a decision‐making context, we created a hypothetical case study and used it to compare different risk mitigation strategies for reducing contamination and spread of Listeria monocytogenes in a food facility. Model results indicated that areas with no direct contact with foods (e.g., loading dock and restroom) can serve as contamination niches and recontaminate areas that have direct contact with food products. Furthermore, food handlers’ behaviors, including, for example, hygiene and sanitation practices, can impact the persistence of microbial contamination in the facility environment and the spread of contamination to prepared foods. Using this case study, we also demonstrated benefits of an ABM framework for addressing food safety in a complex system in which emergent system‐level responses are predicted using a bottom‐up approach that observes individual agents (e.g., food handlers) and their behaviors. Our model can be applied to a wide variety of pathogens, food commodities, and activity patterns to evaluate efficacy of food‐safety management practices and quantify contamination reductions associated with proposed mitigation strategies in food facilities.     

On the odd girth and the circular chromatic number of generalized Petersen graphs

A class \(\mathcal{G}\) of simple graphs is said to be girth-closed (odd-girth-closed) if for any positive integer g there exists a graph \(\mathrm {G} \in \mathcal{G}\) such that the girth (odd-girth) of \(\mathrm {G}\) is \(\ge g\). A girth-closed (odd-girth-closed) class \(\mathcal{G}\) of graphs is said to be pentagonal (odd-pentagonal) if there exists a positive integer \(g^*\) depending on \(\mathcal{G}\) such that any graph \(\mathrm {G} \in \mathcal{G}\) whose girth (odd-girth) is greater than \(g^*\) admits a homomorphism to the five cycle (i.e. is \(\mathrm {C}_{_{5}}\)-colourable). Although, the question “Is the class of simple 3-regular graphs pentagonal?” proposed by Ne?et?il (Taiwan J Math 3:381–423, 1999) is still a central open problem, Gebleh (Theorems and computations in circular colourings of graphs, 2007) has shown that there exists an odd-girth-closed subclass of simple 3-regular graphs which is not odd-pentagonal. In this article, motivated by the conjecture that the class of generalized Petersen graphs is odd-pentagonal, we show that finding the odd girth of generalized Petersen graphs can be transformed to an integer programming problem, and using the combinatorial and number theoretic properties of this problem, we explicitly compute the odd girth of such graphs, showing that the class is odd-girth-closed. Also, we obtain upper and lower bounds for the circular chromatic number of these graphs, and as a consequence, we show that the subclass containing generalized Petersen graphs \(\mathrm {Pet}(n,k)\) for which either k is even, n is odd and \(n\mathop {\equiv }\limits ^{k-1}\pm 2\) or both n and k are odd and \(n\ge 5k\) is odd-pentagonal. This in particular shows the existence of nontrivial odd-pentagonal subclasses of 3-regular simple graphs.     

Evaluation of corporate governance systems by credit rating agencies

In periods of high market volatility, and in order to minimize their risks, some investors prefer to invest their funds in well-governed companies. This paper aims to describe the methodology used by rating agencies to assess corporate governance systems (CGS) and to compare agencies’ practices. More and more the shareholders and creditors incorporate mechanisms related to CGS in the assessment of risks. Using a sample of five rating agencies, we distill 51 governance criteria to two governance factors using principal components analysis. The first factor represents the “shareholders rights and board of directors”. The second one is related to “remuneration policy and convergence of interests for shareholders and managers”. We identify three different business models for the corporate governance rating process.     

«Il n'y a pas d’avenir dans ce métier.» Être chauffeur de VTC en Afrique par temps de pandémie

Si les plateformes ont donné du travail à beaucoup d’Africains, les emplois créés sont de mauvaise qualité, comme la pandémie l'a bien montré. Dans ce contexte, les auteurs examinent la situation particulière des chauffeurs VTC en Afrique en s'appuyant sur des entretiens approfondis, réalisés au Kenya, et sur les méthodes de l'ethnographie virtuelle. Ils montrent que ces travailleurs ont recours à un «régime de débrouille», associant résilience, réajustement et résistance. Pour améliorer les conditions de travail et lutter contre la précarité dans le secteur, il faut à la fois que les pouvoirs publics instaurent des cadres réglementaires et que les travailleurs se mobilisent collectivement.     

The Fundamental Endogeneity of Survey-Based Cultural Dimension

Survey-based cultural dimensions are used extensively in empirical analysis as the primary source of quantitative cultural scores. However, survey-based cultural dimensions have a significant endogeneity problem. The individuals responding to the surveys are affected by their current socioeconomic condition and environment (social mood), meaning that the outcomes are a mixture of culture and current socioeconomic effects. The World Value Survey (WVS) waves provided empirical support for the endogeneity problem. Our empirical findings show that in-country scores frequently change between waves. In addition, the countries in the WVS change their ranking between waves; so, even the relative position held by a country is questionable when measured along survey-based cultural dimensions. This finding contrasts with the idea that cultural values are sticky. We provide an alternative method for capturing cultural dimensions based on the grammatical structures of languages that capture ancestral culture with no fear of the current socioeconomics pollution of the measure.     

A Predictive Model for Survival of Escherichia coli O157:H7 and Generic E. coli in Soil Amended with Untreated Animal Manure

This study aimed at developing a predictive model that captures the influences of a variety of agricultural and environmental variables and is able to predict the concentrations of enteric bacteria in soil amended with untreated Biological Soil Amendments of Animal Origin (BSAAO) under dynamic conditions. We developed and validated a Random Forest model using data from a longitudinal field study conducted in mid-Atlantic United States investigating the survival of Escherichia coli O157:H7 and generic E. coli in soils amended with untreated dairy manure, horse manure, or poultry litter. Amendment type, days of rain since the previous sampling day, and soil moisture content were identified as the most influential agricultural and environmental variables impacting concentrations of viable E. coli O157:H7 and generic E. coli recovered from amended soils. Our model results also indicated that E. coli O157:H7 and generic E. coli declined at similar rates in amended soils under dynamic field conditions.The Random Forest model accurately predicted changes in viable E. coli concentrations over time under different agricultural and environmental conditions. Our model also accurately characterized the variability of E. coli concentration in amended soil over time by providing upper and lower prediction bound estimates. Cross-validation results indicated that our model can be potentially generalized to other geographic regions and incorporated into a risk assessment for evaluating the risks associated with application of untreated BSAAO. Our model can be validated for other regions and predictive performance also can be enhanced when data sets from additional geographic regions become available.     

The social work services in screening process of compulsory treatment interventions in addicts in Iran: A content analysis study

Compulsory treatment has had a detrimental impact on drug abuse treatment policies and programs in Iran. Physicians are currently required to conduct initial treatment screening. Social workers are a part of the treatment team but have no authority to initiate a compulsory drug treatment plan. For this reason, the present article investigates social work service participation in the process of compulsory drug treatment. The study methodology is content analysis. Nine social workers participated in seven focus group discussions. Overall, 110 codes were extracted from the sessions and were categorized into five main themes: interview and initial assessment; referral; investigation of ineligibility criteria; report to judicial authority; and follow‐up and advocacy. The results of this research suggest amending executive bylaws based on a social work approach to the screening process for compulsory drug treatment.