100 research outputs found
Uso de variables de mercado en la predicción de dificultades financieras para las empresas que cotizan en Vietnam
This paper aims to investigate the classification power of market variables as predictors in the financial distress prediction model for listed companies in a frontier market as Vietnam securities market. Data is collected from 70 financially distressed companies that suffer a loss in 3 consecutive years and 156 non-financially distressed companies in Vietnam from 2010 to 2017. Four different models have been constructed using Logit regression and SVM analysis technique to make a prediction in 1 to 3-year ahead. The analysis results show that combining accounting ratios with market variables such as price volatility and P/E can improve the classification ability of the ex-ante model. In addition, contrary to the results of related previous researches in emerging markets, in this study, Logit models outperform SVM models. Therefore, for future research, models that apply other machine learning classifiers such as Decision Tree (DT) or Neural Network (NN) should be investigated.Este artículo tiene como objetivo investigar el poder de clasificación de las variables del mercado como factores predictivos en el modelo de predicción de dificultades financieras para las empresas que cotizan en bolsa en un mercado fronterizo como el mercado de valores de Vietnam. Los datos se recopilan de 70 compañías con dificultades financieras que sufrieron una pérdida en 3 años consecutivos y 156 empresas sin dificultades financieras en Vietnam desde 2010 a 2017. Se han construido cuatro modelos diferentes utilizando regresión Logit y la técnica de análisis de SVM para hacer una predicción en 1 a 3 años por delante. Los resultados del análisis muestran que la combinación de ratios contables con variables de mercado como la volatilidad de los precios y el P / E puede mejorar la capacidad de clasificación del modelo ex ante. Además, a diferencia de los resultados de investigaciones anteriores relacionadas en mercados emergentes, en este estudio, los modelos Logit superan a los modelos SVM. Por lo tanto, para futuras investigaciones, se deben investigar los modelos que aplican otros clasificadores de aprendizaje automático, como el Árbol de decisiones (DT) o la Red neuronal (NN)
Indochinese bamboos: biodiversity informatics to assist the identification of “vernacular taxa”
Bamboo (Bambusoides – Gramineae) is one of the most
important natural resource in Southeast Asia. However, bamboo identification
has many difficulties. In the area of SEP programme «Indochina Bamboos»
(2008-2010), the final objective is to update the bamboo flora of Indochine
(Vietnam, Laos, Cambodege) and to publish an e-flora including free access
keys, digital images and information about the traditional and economic use
of bamboos. During field trips in Vietnam, Laos and Cambodgia, samples,
pictures and morphological description sheets were collected in various
locations and previously assigned to the local vernacular names. We use
an informatic program, Xper2, to assist the comparison and identification of
“vernacular bamboo taxa” based on morphological characteristics
Straightforward Procedure for Laboratory Production of DNA Ladder
DNA ladder is commonly used to determine the size of DNA fragments by electrophoresis in routine molecular biology laboratories. In this study, we report a new procedure to prepare a DNA ladder that consists of 10 fragments from 100 to 1000 bp. This protocol is a combination of routinely employed methods: cloning, PCR, and partial digestion with restriction enzymes. DNA fragments of 100 bp with unique restriction site at both ends were self-ligated to create a tandem repeat. Once being cloned, the tandem repeat was rapidly amplified by PCR and partially digested by restriction enzymes to produce a ladder containing multimers of the repeated DNA fragments. Our procedure for production of DNA ladder could be simple, time saving, and inexpensive in comparison with current ones widely used in most laboratories
TURBIDITY REMOVAL BY MUCILAGE FROM BASELLA ALBA
Coagulation and flocculation are preliminary used in water treatment processes for turbidity removal, using popularily synthetic chemicals with health and environmental concerns. The use of natural flocculants has known to be a promising alteratives for chemical ones due to their environmental friendly behavior. This research investigated turbidity removal efficiency of mucilage extracted from Basella alba - an indigenous species in Vietnam - in the role of a flocculant. The removal efficiency of mucilage was investigated in combination with PAC or Alum on To Lich river water by mean of Jar tests. PAC or Alum alone can remove maximum 97% and 90% turbidity of To Lich river water at its original pH for the sedimentation time of 30 minutes. The combination of mucilage and PAC or Alum increased the efficiencies of turbidity removal and reduced the amount of chemicals needed. The corresponding increases were maximum 7% and 18%, respectively; while the reduction of PAC/Alum used was 75-80%
Genome-wide association mapping of leaf mass traits in a Vietnamese rice landrace panel
Leaf traits are often strongly correlated with yield, which poses a major challenge in rice breeding. In the present study, using a panel of Vietnamese rice landraces genotyped with 21,623 single-nucleotide polymorphism markers, a genome-wide association study (GWAS) was conducted for several leaf traits during the vegetative stage. Vietnamese landraces are often poorly represented in panels used for GWAS, even though they are adapted to contrasting agrosystems and can contain original, valuable genetic determinants. A panel of 180 rice varieties was grown in pots for four weeks with three replicates under nethouse conditions. Different leaf traits were measured on the second fully expanded leaf of the main tiller, which often plays a major role in determining the photosynthetic capacity of the plant. The leaf fresh weight, turgid weight and dry weight were measured; then, from these measurements, the relative tissue weight and leaf dry matter percentage were computed. The leaf dry matter percentage can be considered a proxy for the photosynthetic efficiency per unit leaf area, which contributes to yield. By a GWAS, thirteen QTLs associated with these leaf traits were identified. Eleven QTLs were identified for fresh weight, eleven for turgid weight, one for dry weight, one for relative tissue weight and one for leaf dry matter percentage. Eleven QTLs presented associations with several traits, suggesting that these traits share common genetic determinants, while one QTL was specific to leaf dry matter percentage and one QTL was specific to relative tissue weight. Interestingly, some of these QTLs colocalize with leaf- or yield-related QTLs previously identified using other material. Several genes within these QTLs with a known function in leaf development or physiology are reviewed
Factors Influence on Promotion Mix in E-marketing: Case of Technology Services Enterprise in Vietnam
Purpose: The objective of this study is to clarify factors affecting the promotion mix in E-Marketing, with specific target audience being enterprises operating in the technology service industry in Vietnam.
Theoretical framework: Based on the promotion theory and social exchange theory, this study focuses on the factors that influence on the promotion decision in firms.
Design/Methodology/Approach: This study applies both qualitative and quantitative methods with data collected from a questionnaire survey.
Findings: There are 4 factors respectively Sales Promotion, Advertising, Public Relations and Personal Selling that affect the mixed promotion activities in E-Marketing of technology service enterprises in Vietnam.
Research, practical & social implications: This study propose solutions to improve the promotion activities in the e – marketing of firms in Vietnam.
Originality/Value: This study is one of the early studies that have focused in this field in Vietnam.Propósito: El objetivo de este estudio es aclarar los factores que afectan la combinación de promoción en E-Marketing, con un público objetivo específico que son las empresas que operan en la industria de servicios de tecnología en Vietnam.
Marco teórico: Basado en la teoría de la promoción y la teoría del intercambio social, este estudio se centra en los factores que influyen en la decisión de promoción en las empresas.
Diseño/metodología/enfoque: este estudio aplica métodos cualitativos y cuantitativos con datos recopilados de una encuesta de cuestionario.
Hallazgos: Existen 4 factores, respectivamente, Promoción de Ventas, Publicidad, Relaciones Públicas y Ventas Personales que afectan las actividades mixtas de promoción en E-Marketing de las empresas de servicios de tecnología en Vietnam.
Implicaciones de investigación, prácticas y sociales: este estudio propone soluciones para mejorar las actividades de promoción en el marketing electrónico de las empresas en Vietnam.
Originalidad/valor: Este estudio es uno de los primeros que se han centrado en este campo en Vietnam.Objetivo: O objetivo deste estudo é esclarecer os fatores que afetam o mix de promoção no E-Marketing, tendo como público-alvo específico as empresas que operam no setor de serviços de tecnologia no Vietnã..
Referencial teórico: Com base na teoria da promoção e na teoria das trocas sociais, este estudo se concentra nos fatores que influenciam a decisão de promoção nas empresas..
Desenho/metodologia/abordagem: Este estudo aplica métodos qualitativos e quantitativos com dados coletados de uma pesquisa por questionário.
Resultados: Existem 4 fatores, respectivamente, Promoção de Vendas, Publicidade, Relações Públicas e Vendas Pessoais que afetam as atividades de promoção mista em E-Marketing de empresas de serviços de tecnologia no Vietnã.
Pesquisa, implicações práticas e sociais: Este estudo propõe soluções para melhorar as atividades de promoção no e – marketing de empresas no Vietnã.
Originalidade/valor: Este estudo é um dos primeiros estudos que se concentraram neste campo no Vietnã.
Palavras-chave: Mix de promoção; E-Marketing; Serviços de tecnologia; Vietn
Dengue Haemorrhagic Fever in the South of Vietnam during 1975-1992 and Its Control Strategy
The incidence of dengue (DEN) virus infection in Vietnam has increased dramatically in the past 30 years. From 1960 up to now, the number of dengue haemorrhagic fever (DHF) cases has been continuing to increase and recorded as the greatest one in Southeast Asia and the Western Pacific Regions. DHF was endemic in South Vietnam and 30-380 cases/100,000 population were reported annually. Major epidemics have occurred in a 3-4 years frequency, as in 1975, 1978-1979, 1983 and 1987. The 1987 outbreak was the largest one with 83,905 cases and 904 deaths. DHF epidemics usually took place from June to November every year. The peak transmission was recorded in July-August and September, coinciding with the rainy season and the breeding period of Aedes aegypti. The majority of confirmed cases was children of 5-6 year-old-group, in which there was no sex difference. In the virological surveillance in Ho Chi Minh City and in some surrounding provinces, several DEN virus strains were isolated from patients\u27 blood as well as from the mosquitoes. In the 1987 DHF outbreak, DEN-2 was the dominant sero-type (90.5%). But from 1990 the epidemic sero-type has changed, DEN-1 was introduced and was continuing to grow-up (58%). Then in 1992 outbreak, the DEN-2 was reintroduced, from 26.3% in 1991 has increased to 41.4%. Serological investigation of healthy persons in 12/17 southern provinces had demonstrated that there were relatively wide circulations of DEN, Japanese encephalitis (JE) and chikungunya (Chik) viruses and the endemic strains of DEN were found different in some studied areas. There had been augmentation of primary infection rate and decrease of the susceptibility rate in children prior to the DHF epidemic. Seven JE virus strains were isolated from dengue fever (DF) patients\u27 blood. This fact has introduced as a new concept in the isolation of JE virus. In the final pant of the report, the authors stressed on the "Active surveillance" as a new strategy for controlling the DHF epidemic in South Vietnam. The goal of this active surveillance is to have early warning and predictive capability for epidemic dengue, based on serological and clinical surveillance. Because dengue cases were detected in January-February of every year, so the base line is: when first cases of DF/DHF were detected, it needs to be promptly implemented the larval control and insecticide must be sprayed around the patient\u27s houses. But now almost Provincial Centers of Hygiene and Epidemiology often waited and when big DHF epidemic had already occurred, they started to implement its control measures, so it is too late to control the DHF outbreak
- …