bluuebunny/crossref_metadata_2025 huggingface dataset:
Fabrication Membrane of Titanium dioxide (TiO2) Blended Polyethersulfone (PES) and Polyvinilidene fluoride (PVDF): Characterization, Mechanical Properties and Water Treatment
Authors: Mataram Agung , Anisya Nyanyu , Nadiyah Nyayu Ayu , Afriansyah Afriansyah
Published: October 2020

In this research, Polyethersulfone (PES) and Polyvinylidene Fluoride (PVDF) with the addition of a Titanium Dioxide (TiO2) blanded membrane were prepared using the DC 15000 V electric field method. The investigation of this research is the adding result of Titanium Dioxide (TiO2) with the DC 15000 V electric field methos such as the mechanical properties of membranes and water treatment performance. The surface mixture of Polyethersulfone (PES) and Polyvinylidene Fluoride (PVDF) membranes is characterized using SEM, the membrane pore size shrinks and forms evenly with the addition of Titanium Dioxide (TiO2) and DC electric field methods. Tensile tests were carried out to obtain the mechanical properties of Polyethersulfone (PES) and Polyvinylidene Fluoride (PVDF) by adding Titanium Dioxide (TiO2) mixture membrane, which showed an increase in optimal tensile strength to 3.86 MPa at a concentration of 30% Polyethersulfone (PES) and also increased to 1.15 MPa at 20% Polyvinylidene Fluoride (PVDF). The membrane surface was examined using contact angle measurements, which in the mixed membrane Polyethersulfone (PES) and Polyvinylidene Fluoride (PVDF) showed a decrease in the angle between the range of 43o - 46o. Therefore, hydrophilicity makes it possible to suppress the permeate flux of pure water. Making membranes with the addition of Titanium Dioxide (TiO2), and assisted by DC electric fields opens up new ways to increase membrane strength, hydrophilicity, shrink and make pore sizes evenly formed.
Improving of Electric Voltage Response Based on Improving of Electrical Properties for Multiferroic Material of BiFeO3-BaTiO3 System
Authors: Suastiyanti Dwita , Maulida Yuli Nurul , Wijaya Merlin
Published: October 2020

Synthesis of nanomultiferroic material with the active content of bismuth ferrite (BiFeO3) and barium titanate (BaTiO3) was carried out. It is considering that it was difficult to obtain single phase of BiFeO3 as a base material for multiferroic materials. It is expected that the addition of BaTiO3 on ceramic alloys consist of BiFeO3 and BaTiO3 can improve the electrical properties of the ceramics and finally it improves the multiferroic properties of the material. Multiferroic properties could be seen from the appearance of an electric voltage response if the material is given the effect of an external magnetic field. The synthesis uses the sol gel method which is a good method of producing nanosized material. Synthesis of nanomultiferroic ceramic materials is carried out by varying the weight ratio of BaTiO3 and BiFeO3 of 2: 1, calcination temperature of 350°C for 4 hours and sintering temperatures with variations of 700°C; 750°C and 800°C for 2; 4; and 6 hours. Characterization was carried out using X Ray Diffraction (XRD) to confirm phase formation. The electrical properties test which produces a hysterical loop is carried out to determine the value of remanent, coercivity and electric polarization saturation. Particle size measurements were carried out using the Beckman Coulter DelsaTM nanoinstrument. The multiferroic phenomena is known from the appearance of an electric voltage response if there is an effect of an external magnetic field on the material. The smallest particle size was obtained on ceramic powder which experienced sintered of 750°C. The best values of remanent, coercivity and electric polarization​​ were obtained on ceramics which were sintered at temperatures of 750°C for 6 hours. This is linear with the highest value of electrical voltage arising as a result of the effect of the external magnetic field given to the ceramic material. Material that has a large electrical voltage response shows good multiferroic properties.
Natural Fiber Reinforced Composites as Bulletproof Panel Materials
Authors: Sutikno Sutikno , Safaat Ahmat , Fendy Kussuma H.S.
Published: October 2020

The panel attached in bulletproof vests must fulfill the standard of NIJ 0101.06. It must resist the penetration of the bullet and has a back-face signature that does not exceed 44 mm by ballistic testing. This research included both numerical simulation and ballistic tests for validation using type IV ballistic bullet. This research involved composite epoxy-HGM-hemp (Boehmeria Nivea) and epoxy-HGM-sisal (Agave Sisalana) as bulletproof panel materials with their woven-thickness characteristic. The properties of materials are obtained by performing ASTM D3039 test. As a result, by varying the thickness or each amount of layer, the thinnest panel of each material that fulfills the standard of NIJ 0101.06 is obtained.
Effect of Stirring on the Quality of ADC 12 Cast Aluminium Alloy
Authors: Agustin Helena C. Kis , Sidharta Indra , Leonard Leonard
Published: October 2020

Stirring is one the most utilized process in small foundry. It is used for homogenizing the temperature and mixing process during melting. However, stirring may cause undesirable effect to the quality of castings if it is not managed properly. Bifilm is one of the defects that can be detrimental to the quality of aluminium castings, and its formation can be related to the stirring during melting. The research aim is to investigate the effect of stirring during melting of cast aluminium alloys. The quality of castings is approached by the term of bifilm index and mechanical properties. ADC 12 cast aluminium alloys is used in the experiment. The ADC 12 ingots are melted at 720 °C, and then stirred for 0, 3 and 5 minutes. Reduced Pressure Test is used for determining the bifilm index. Samples for mechanical testing are also casted into specific geometry. Results indicate that prolonged stirring time increases the bifilm index, indicating that more porosity and bifilm oxide are formed. Extended stirring time instigates more turbulence in liquid metal, hence surface oxides are folded and trapped in the bulk liquid metal. Charpy impact test, hardness test and tensile test have also carried out. More Porosity and bifilm oxide are formed in the samples and tend to decrease the mechanical property.
Role of Tunneling Nanotube–like Structures during the Early Events of HIV Infection: Novel Features of Tissue Compartmentalization and Mechanism of HIV Spread
Authors: Okafo George , Valdebenito Silvana , Donoso Maribel , Luu Ross , Ajasin David , Prideaux Brendan , Gorantla Santhi , Eugenin Eliseo A.
Published: October 2020

HIV has become a chronic disease despite the effective use of antiretroviral therapy (ART). However, the mechanisms of tissue colonization, viral evolution, generation of viral reservoirs, and compartmentalization are still a matter of debate due to the challenges involved in examining early events of infection at the cellular and molecular level. Thus, there is still an urgent need to explore these areas to develop effective HIV cure strategies. In this study, we describe the early events of tissue colonization and compartmentalization as well as the role of tunneling nanotube–like structures during viral spread in the presence and absence of effective antiretroviral treatment. To examine these mechanisms, NOD/SCID IL-2 RG−/− humanized mice were either directly infected with HIVADA or with low numbers of HIVADA–infected leukocytes to limit tissue colonization in the presence and absence of TAK779, an effective CCR5 blocker of HIV entry. We identify that viral seeding in tissues occurs early in a tissue- and cell type–specific manner (24–72 h). Reduction in systemic HIV replication by TAK779 treatment did not affect tissue seeding or spreading, despite reduced systemic viral replication. Tissue-associated HIV-infected cells had different properties than cells in the circulation because the virus continues to spread in tissues in a tunneling nanotube–like structure–dependent manner, despite ART. Thus, understanding these mechanisms can provide new approaches to enhance the efficacy of existing ART and HIV infection cure strategies.
Patient-centred care: The patients’ perspective – A mixed-methods pilot study
Authors: Turner Roseanne E. , Archer Elize
Published: October 2020

Background: Patient centredness is a broad concept, a moral philosophy. Patient-centred care can be viewed as the actions of patient-centredness. One of the most pertinent actions that a healthcare practitioner can utilise to deliver patient-centred care is empathic communication. Whilst many medical programmes include empathetic communication skills as part of their curricula, the recipients of this care are not asked about the relevance of this teaching.Aim: We attempted to determine whether the Western constructs of empathy were relevant in our context and also establish whether there were any parts of the medical interview which participants felt were especially important to be communicated to in their home language.Setting: Two urban communities within the City of Cape Town, Western Cape Province, South Africa.Methods: This was a mixed-methods pilot study using an explanatory sequential design. Participants who would typically make use of public health care facilities and whose first language was Afrikaans or isiXhosa were conveniently sampled. A subgroup of participants was invited to take part in a follow-up focus group discussion to add clarity to the survey responses.Results and Conclusion: Western constructs for empathy appeared to be relevant within our multicultural context. Patients wanted to communicate with their doctors and understand the cause of their problems as well as the management plan. Finally, whilst the numbers in this pilot study were too small to be generalisable, it was evident that patient-centred care was not perceived to be implemented in some public healthcare facilities attended by the participants, which resulted in them feeling unseen and disrespected.
Rigidity of cones with bounded Ricci curvature
Authors: Erbar Matthias , Sturm Karl-Theodor
Published: October 2020

We show that the only metric measure space with the structure of an

N

-cone and with two-sided synthetic Ricci bounds is the Euclidean space

\mathbb R^{N+1}

for

N

integer. This is based on a novel notion of Ricci curvature upper bounds for metric measure spaces given in terms of the short time asymptotic of the heat kernel in the

L^2

-transport distance. Moreover, we establish rigidity results of independent interest which characterize the

N

-dimensional standard sphere

\mathbb S^N

as the unique minimizer of

\int_X\int_X \cos d (x,y)\, m(\mathrm d y)\,m(\mathrm d x)

among all metric measure spaces with dimension bounded above by

N

and Ricci curvature bounded below by

N-1

.
Trainees' Perceptions of the Transition From Medical School to Residency
Authors: Bell Sarah G. , Kobernik Emily K. , Burk-Rafel Jesse , Hughes David T. , Schiller Jocelyn , Heidemann Lauren A. , Morgan Helen K.
Published: October 2020

Background

There is emerging evidence that learners may be suboptimally prepared for the expectations of residency. In order to address these concerns, many medical schools are implementing residency preparation courses (RPCs).

Objective

We aimed to determine trainees' perceptions of their transition to residency and whether they felt that they benefited from participation in an RPC.

Methods

All residents and fellows at the University of Michigan (n = 1292) received an electronic survey in July 2018 that queried respondents on demographics, whether medical school had prepared them for intern year, and whether they had participated in an RPC.

Results

The response rate was 44% (563 of 1292) with even distribution across gender and postgraduate years (PGYs). Most (78%, 439 of 563) felt that medical school prepared them well for intern year. There were no differences in reported preparedness for intern year across PGY, age, gender, or specialty. Overall, 28% (156 of 563) of respondents participated in an RPC and endorsed feeling prepared for intern year, which was more than RPC non-participants (85% [133 of 156] vs 70% [306 of 439], P = .029). Participation in longer RPCs was also associated with higher perceived preparedness for residency.

Conclusions

This study found that residents from multiple specialties reported greater preparedness for residency if they participated in a medical school fourth-year RPC, with greater perceptions of preparedness for longer duration RPCs, which may help to bridge the medical school to residency gap.
Distribution and molecular analysis of Blastocystis subtypes from gastrointestinal symptomatic and asymptomatic patients in Iran
Authors: Delshad Asma , Saraei Mehrzad , Ali Alizadeh Safar , Rahimi Niaraki Soheila , Alipour Mahmood , Hosseinbigi Bahram , Bozorgomid Arezoo , Hajialilo Elham
Published: October 2020

Introduction: Blastocystis is a common intestinal parasite of human and animal hosts. The parasite has 17 subtypes, and among those at least nine subtypes (ST1-ST9) are found in human hosts.

Objective: The aim of the present study was to investigate the presence of different subtypes of Blastocystis spp. among the patients referred to Velayat hospital of Qazvin province, Iran.

Methods: Overall, 864 stool samples were examined by using formalin-ethyl acetate concentration method and Trichrome staining. All specimens were cultured in clotted fetal bovine medium. Later, DNA extraction and PCR amplification of 18S ribosomal RNA gene region was conducted and phylogenetic tree constructed.

Results: The results revealed 7.9% (68/864) of the study population were infected with Blastocystis. Intestinal symptoms were observed in 61% (36/59) of individuals positive for Blastocystis, with abdominal pain in 58% (21/36) of cases which was more frequent than other intestinal signs. No significant relationship was observed among the study variables. By molecular and phylogenetic analysis, three subtypes ST1 (45%), ST2 (30%) and ST3 (23%) of parasite were identified.

Conclusion: This study showed ST1 subtype was the predominant subtype among the positive specimens, meanwhile the highest haplotype and nucleotide diversity were clarified in ST3 subtype.

Keywords: Blastocystis, subtype, Phylogenetic analysis, Iran.
Mental and personality disorders in infertile women with polycystic ovary: a case-control study
Authors: Ahmadi Mostafa , Faramarzi Mahbobeh , Basirat Zahra , Kheirkhah Farzan , Chehrazi Mohammad , Ashabi Fatemeh
Published: October 2020

Background: Polycystic Ovarian Syndrome (PCOS) is one of the most common causes of infertility in women.

Objective: The current study investigated mental and personality disorders in infertile women with and without PCOS.

Methods: This case-control study evaluated 400 infertile women who referred to the Infertility Center in Babol city (North of Iran). Participants were categorized into the case group (201 PCOS) and the control group (199 without PCOS). All of the participants completed the Millon Clinical Multi-axial Inventory-III (MCMI-III).

Results: The mean scores for clinical personality patterns were significantly higher for six personality disorders (schiz- oid, avoidant, antisocial, depressive, sadistic, and negativistic) and for three classes of severe personality disorder patterns (schizotypal, borderline, and paranoid) in infertile women with PCOS than in women without PCOS. The mean scores for eight clinical disorders (somatoform, manic disorder, dysthymia, alcohol-dependence, drug-dependence, post-trauma stress disorder, major depression, and delusion disorder) were also higher in infertile women with PCOS than in women without PCOS.

Conclusion: The scores of many mental and personality disorders are higher in infertile women with PCOS than in women without PCOS. Thus, clinicians should prioritize recognizing and treating psychological problems of infertile women with PCOS.

Keywords: Polycystic ovarian syndrome; infertility; personality disorders.
Nephroprotective effect of methanol extract of Moringa oleifera leaves on acute kidney injury induced by ischemia-reperfusion in rats
Authors: Stephen Akinrinde Akinleye , Oduwole Olusegun , Joseph Akinrinmade Fadeyemi , Bolawaye Bolaji-Alabi Folusho
Published: October 2020

Background: Moringa oleifera is known to exhibit protection against oxidative damage due to its rich content of compounds with antioxidant activity. This study investigated the protective effect of the methanol extract of Moringa oleifera (MO) in a rat model of renal ischemia-reperfusion (IR) injury.

Methods: Forty two wistar rats were randomly assigned to six groups of seven rats each, as follows: A, control group; B, sham-operated group; C, IR group; D, IR + low dose (200 mg/kg) MO; E, IR + high dose (400 mg/kg) MO and F, IR + Vitamin C (200 mg/kg). Unilateral ischaemia was induced by occluding the left renal artery for 45 minutes followed by rep- erfusion up to 24 hours.

Results: Moringa oleifera significantly (p<0.05) ameliorated IR-induced increases in malondialdehyde (MDA), protein carbon- yls (PC) and advanced oxidation protein products (AOPP), while also decreasing serum BUN and Creatinine levels. More- over, the low dose of MO caused reductions in renal NO and H2O2 levels, while increasing renal GPx and GST activities. Histopathology revealed marked improvement of tissue alterations induced by IR with both doses of MO.

Conclusion: Overall, the methanol extract of M. oleifera effectively attenuated the deleterious effects of renal IR via allevi- ation of tissue oxidative stress.

Keywords: Oxidative stress; ischaemia-reperfusion; Moringa oleifera; kidneys; antioxidants.
From genes polymorphisms to mucosal expression of cytokines: evaluating IL-23/IL-17 axis in adult patients with gastritis
Authors: Azadegan-Dehkordi Fatemeh , Abbasi Ardeshir , Talebi Bezmin Abadi Amin , Minooie Khaled , Aslani Parya , Sadat Hosseini Razieh , Zandi Farid
Published: October 2020

Background and Objective: Chronic inflammation is the typical sign of gastritis that may shift into gastric cancer. IL- 17A and IL-17F as a novel inflammatory cytokines subset of CD4+Th play the main role in inflammation. A key cytokine receptor in the inflammatory IL-17/IL-23 axis, the interleukin 23 receptor (IL23R), may be related to gastritis. We evaluated the correspondence between IL-17A G197A, IL-17F A7488G and IL23R+2199 A/C polymorphisms with TGF-β1, IL-6, IL-17, IL-21 and IL-23 mucosal mRNAs expression in uninfected H. Pylori (HP) chronic gastritis patients.

Materials and Methods: Total RNA and genomic DNA were separated from gastric biopsies of 44 patients with gastritis. Subsequently, mucosal mRNAs expression of TGF-β1, IL-6, IL-17, IL-21 and IL-23 were assessed by real-time PCR. To polymorphisms determination of IL-17A G197A, IL-17F A7488G and IL-23R +2199A/C the PCR-RFLP was used in gastric biopsies.

Results: Results point that IL-17A G197A, IL-17F A7488G and IL23R +2199A/C polymorphisms did not influence the mucosal expression of TGF-β1, IL-6, IL-17 and IL-21 (p> 0.05). In an opposite result, we don’t find a correspondence between IL-17A G197A, IL-17F A7488G polymorphisms and mucosal expression of IL-23 (p> 0.05). In a contrary, we found a correlation between IL23R +2199A/C polymorphism and mucosal expression of IL-23 in patients with chronic gastritis (p< 0.05).

Conclusion: These findings propose that IL23R +2199A/C polymorphism may change the mucosal expression of IL-23 pattern in patients with gastritis disease in the absence of HP, but to support the conclusion, more research may be required.

Keywords: Cytokines; polymorphism; gastritis; IL-23, IL-17.
Magnetic resonance imaging in chronic headache: our experiences and perspectives
Authors: Dorothy Itanyi Ukamaka , Chinedu Okere Philip , Ifeyinwa Iloanusi Nneka , U Uduma Felix
Published: October 2020

Background: Headache is a common symptomatology necessitating hospital consultations. Despite the prohibitive cost to patients in Nigeria, Magnetic resonance imaging (MRI) has become an evaluating tool for headache.

Objectives: To determine the yield of cranial MRI and frequency of significant intracranial lesions among patients with chronic headache.

Methods: A three-year retrospective analysis of cranial MR images and records of patients referred to Medicaid Diagnostic Centre in Abuja, Nigeria on account of chronic headache was done. Data was analyzed using SAS software version 9.3.

Results: 150 patients aged 9 to 73 years (mean= 39.5 years) with chronic headache were studied. There were 54 males and 96 females with a ratio of 1:1.8. 48% and 52% had normal and abnormal MRI findings respectively. Although the number with abnormal MRI was higher than those with normal exams, this difference was not significant (p=0.624). The commonest neoplastic and non-neoplastic abnormalities were pituitary macroadenoma (4%) and sinusitis (21.3%) respectively.

Conclusion: In our study, MRI had a low diagnostic yield in patients with chronic headache. Therefore, it is expedient that physicians stratify patients with chronic headache based on red flag signs to determine the need for cranial MRI in view of financial burden.

Keywords: Chronic headache; MRI; diagnostic yield; sinusitis.
Quality analysis of dual-frequency smartphone-based ionospheric TEC measurements: what can be achieved?
Authors: Bruno Jon , Darugna Francesco , Bolmgren Karl , Wübbena Jannes , Mitchell Cathryn , Schmitz Martin
Published: October 2020

The growing quality of smartphone-based Global Navigation Satellite Systems (GNSS) chipsets opens a new frontier for scientific research in positioning, navigation and timing ap- plications. The portability and affordability of these instruments could enhance the current GNSS receiver global network for atmospheric monitoring purposes. However, the quality of the measurements gathered from smartphones have not yet been fully assessed. In this paper, an analysis of the quality of smartphone-based Total Electron Content (TEC) mea- surements is performed. The primary focus of this work is to provide a general analysis on the potential of using smartphone observations for ionospheric sciences. Dual-frequency phase observations are used to measure the relative TEC. For this experiment, GPS L1/L5 and Galileo E1/E5a observations acquired with the Xiaomi Mi8 and Huawei Mate20 X smartphones were considered. Both devices are equipped with the Broadcom BCM47755 chipset, which enables GNSS dual-frequency measurements. More than 100 hours of phase observations at mid-latitude during a low solar activity period were gathered. Three differ- ent setup configurations were defined to assess the effects multipath or signal strength may have in the quality of the phase observations. In addition, to detect and discard unrealistic fluctuating phase observations, a quality-check was performed. In the results, good agree- ment between the slant TEC (sTEC) measurements from the smartphone and the sTEC obtained from a co-located geodetic receiver is presented. Furthermore, the amount and quality of observations discarded by the quality-check are reported, which emphasises the use of the signal strength to indicate the quality of phase observations. The results indicate that the C/N0 and multipath are important —when gathering the data from a geodetic antenna, around 80% of the collected data passed a quality threshold. However, collecting data with the addition of an attenuator, or directly from the smartphone antenna, reduced the valid data to below 50%. However, given the ease of use of a smartphone for data collection, even at 50% of data being usable, this shows potential as a useful course of TEC for ionospheric observations.
O spotkaniach Andrzeja Pelczara z matematykami francuskimi w roku akademickim 1967/68
Authors: Domoradzki Stanisław
Published: October 2020

W artykule przybliżamy pobyt A. Pelczara (1937–2010) we Francji i jego spotkania z matematykami pracującymi i goszczącymi w prestiżowym Institut des hautes études scientifiques w Bures-sur-Yvette (IHÉS) i Université Paris XI (Faculté des Sciences d’Orsay). Przyszły twórca krakowskiej szkoły układów dynamicznych miał okazję spotkać, m.in. następujących matematyków: M. Artin, A. Grothendieck, N. Kuiper, B. Malgrange, J. Mather, P. Deligne, R. Thom, Ch. Zeeman.  Artykuł powstał dzięki wspomnieniom współuczestnika pobytu we Francji – Jacka Bochnaka, dzisiaj znanego profesora Vrije Universiteit Amsterdam. On Andrzej Pelczar’s meetings with French mathematicians in the academic year 1967/68 The article familiarizes the readers with the stay of A. Pelczar (1937–2010) in France and his encounters with mathematicians working and staying in the prestigious Institut des Hautes Études Scientifiques in Bures-sur-Yvette (IHÉS) and Université Paris XI (Faculté des Sciences d’Orsay). The future founder of the Kraków school of dynamical systems had an opportunity to meet the following mathematicians, among others: M. Artin, A. Grothendieck, N. Kuiper, B. Malgrange, J. Mather, P. Deligne, R. Thom, Ch. Zeeman. The article was written thanks to the memories of Jacek Bochnak, the companion of Pelczar in France, nowadays a renowned professor of the Vrije Universiteit Amsterdam.
Factors affect cost management accounting application of manufacturing enterprises – An experimental research in southern Vietnam
Authors: Thong Vu Quoc
Published: October 2020

To identify factors affecting cost management accounting application of manufacturing enterprises is a challenge. By qualitative approach, we propose our research model and five hypothesises. During the implementation, we survey 179 manufacturing enterprises in southern Vietnam. Then, the research model is Cronbach Alpha tested, conducted exploratory factor analysis and run gression analysis to explain our proposed hypothesis. The result indicates there are 26 variables from Vietnamese manufacturing enterprise’s managers view grouped into 5 factors affecting the cost management accounting application. These factors are manager’s cognition, accountant’s professional level, enterprise size, IT application level and decentralized administration. The paper conclusion progressively paves the way for further researches on cost management accounting application.
Factors impact on the effectiveness of internal control systems in credit facilities in Binh Thuan province commercial Banks
Authors: Phuoc Nguyen Kim , Ngoc Vo Thi Que
Published: October 2020

The study aims to confirm and measure factors that affect the effectiveness of internal control systems in credit facilities in Binh Thuan province commercial banks. This research used the framework by COSO 2013 and results of expert interviews to offer research models and scales. It was carried out for collecting data from 300 managers and employees of 10 commercial banks (30 people/bank) in Binh Thuan province in 2020. The study used a 5-level likert scale and used SPSS 22.0 software for analysis. The results of multivariate regression analysis (OLS) show that all factors: Risk assessment, Risk management, Control environment, Control procedure, Control activities, Credit control, Control capacity , Information, Communicates internally, Communicates externally have an impact on the effectiveness of internal control systems in credit facilities of commercial Banks in Binh Thuan province.
Thailand institutional framework for FTA negotiation
Authors: Suphachalasai Suphat , Mephokee Chanin , Yoonaidharma Sudharma , Khumon Prapanpong , Chan Natharika , Winyuhuttakit Pakorn , Jarungsri Nattakhanya
Published: October 2020

This article aims to analyze institutional framework relating to the implementation of international trade and investment agreements, especially Free Trade Agreements (FTAs), which Thailand is a member country and going to be a member country, to recommend appropriate guidelines for integration of process and institution to comply with commitments under international trade and investment agreements. The article covers an overview of the institutional mechanism and process of establishing agreement and the implementation of specific areas such as Technical Barriers to Trade (TBT). The article indicates problems of integration of institutional framework in Thailand and renders important recommendations both for general issues (such as Thai government should formulate strategy and create strategic roadmap for trade and investment negotiation) and for specific issues (such as Thailand should conduct a periodical review of existing technical standards to assess their compliance with FTAs).

This article is based on a research project named “Thailand’s Institutional Reform in the Face of International Trade and Investment Obligations” of International Institute for Trade and Development (ITD) conducted using several research methodologies including documentary research, field survey, in-depth interviews and focus group.
A conceptual framework of virtual team effectiveness from the socio-technical perspective
Authors: Chau Huynh Thi Minh , Tuan Nguyen Manh
Published: October 2020

In the era of globalization and technologization, virtual teamwork has become a routine part of professional activity in the software industry and other industries. Understanding virtual team effectiveness helps the management to improve the overall effectiveness of organizations. In this paper, we conduct a literature review of team research to set up a conceptual framework of virtual team effectiveness based on the socio-technical perspective and Inputs-Mediators- Outputs-Inputs model. Our framework includes some salient inputs, mediators and outputs of virtual team life-cycle; specifically, technology readiness and intention to explore are two technical antecedents; team learning and transactive memory system are two social antecedents; and team performance is a socio-technical output representing virtual team effectiveness. After that, a 27-item measuring instrument of aforesaid concepts is proposed after a qualitative survey of 19 virtual team leaders and a quantitative survey of 151 virtual team members from 19 companies locating in Vietnam. The results are references for those interested in improving virtual team effectiveness.
Determinants of consumers’ purchasing intentions toward organic foods: A study in Ho Chi Minh City, Vietnam
Authors: Minh Ha Thi Phuong , Nhan Duong Trong
Published: October 2020

Applying the Theory of Planned Behavior (TPB) this research investigates the factors explaining the purchasing intention of organic food among consumers living in Ho Chi Minh City, Vietnam, and identifies factors influencing their attitude toward buying organic foods. The quantitative method with Exploratory Factor Analysis (EFA), Confirmatory Factor Analysis (CFA) and Structural Equation Model (SEM) from 370 valid questionnaires were used. The study found that health consciousness & food safety, environmental consciousness & consumer knowledge, and availability product impact significantly on consumer attitude toward buying organic food; Customer attitude, subjective norm, and perceived behavioral control have a significant influence on their purchasing intention. The findings of the study provide useful information to marketers for increasing organic food consumption in Vietnam. The findings imply that marketing activity should focus on the change of people’s attitude and lifestyles to increase the consumption of organic food in Ho Chi Minh City.
Research on selective sequence of appropriate mining technology for placer titanium mines in Binh Thuan province
Authors: Le Thao Qui , Bui Nam Xuan , Vu Hieu Dinh , Le Hoa Thu Thi ,   Department of Surface Mining, Mining Faculty, Hanoi University of Mining and Geology  Vietnam Institute of Seas and Islands, Vietnam
Published: October 2020

Binh Thuan province has significant reserves of placer titanium, occupies approximately 92% total reserves of Vietnam. Geological condition of the deposit is quite uncomfortable for mining activities. At present, selection of appropriate mining technology for placer titanium mines in Binh Thuan province is a scientific and practical problem. In this paper, authors researched and developed a selective sequence of appropriate mining technology for placer titanium mines in Binh Thuan province, consists of (1) feasible mining technological schemes, (2) appropriate mining order, (3) possibility of providing water for mine, (4) ensuring slope stability, (5) comfortable alternatives for land rehabilitation and restoration, and (6) high economic effect. With this selective sequence, the appropriate mining technology for placer titanium mines in Binh Thuan province can be selected, and contributes to enhance mining effect, ensures safety and protect environment.
Título en español.
Authors: J. Roldán-Regús  , Luis H. Meyer  , Robert A. Luse
Published: October 2020

Se estudió el efecto de agentes humectantes, a tres concentraciones distintas, sobre la absorción de fosfatos aplicados foliarmente. La concentración de 0.1 por ciento del agente humectante probó ser la mejor para trabajar, porque inducía la máxima absorción del fosfato en todos los casos. El orden de la eficacia de los agentes humectantes, según su habilidad para aumentar la absorción del fósforo por la planta, fue como sigue: Tergitol 7 > Sterox AJ-10 > Agricultural Surfactant > Atlox 210 > Triton X-400 > Atlox 209 > Glycerine. Tanto el Tergitol como el Sterox A-J 100 causan aumentos en la absorción de fósforo, mientras que la glicerina reduce la absorción cuando se asperjó sobre las hojas (14,19). La absorción máxima de los ortofosfatos de sodio, potasio y amonio, aplicados foliarmente, se encontró que ocurrió en los niveles de pH 5, 3 y 10, respectivamente. Según los eñala la literatura (19), la absorción del fosfato varía con el catión acompañante, el pH de la solución aplicada y el tiempo en que la solución que se aplique este en contacto con la joja. El tiempo requerido para obtener un 50 por ciento de absorción del ortofosfato de potasio por la hoja en una planta de caña de azúcar de 1 mes de sembrada fue 18 días. Bw-r et al. (8) informaron que la razón de absorción comparativa para la caña de azúcar es de 15 días.
Título en español.
Authors: H. Irizarry  , H. Azzam  , R. Woodbury
Published: October 2020

En febrero 1959, se llevó a cabo un experimento para determinar el efecto y el valor que pueda tener una cubierta de papel negro de polietileno sobre la producción de tomates en Puerto Rico. Se usaron cuatro tratamientos y cinco variedades en un diseño de bloque al azar con cuatro repeticiones. Los tratamientos combinados fueron como sigue: 1. Surcos cubiertos con el plástico negro, sin desyerbar, y dejando que las plantas crecieran sin soportes. 2. Surcos al descubierto, desyerbados a mano, y dejando que las plantas crecieran sin soportes. 3. Surcos al descubierto, sin desyerbar, y dejando que las plantas crecieran sin soportes. 4. Surcos al descubierto, desyerbados a mano, y dejando que las plantas crecieran con soportes. Las variedades incluidas en este estudio fueron Rutgers, Platillo, Plamar y dos líneas desarrolladas en la Estación, P.R. 123 y P.R. 126. Los resultados de esta prueba indican que la cubierta con el plástico negro impidió el crecimiento de todos los yerbajos, excepto el coquí, Cyperus rotundus L., pero el costo por acre cuando se comparó con el desyerbo a mano fue un factor limitativo. En cuanto a la producción, no se observaron diferencias significativas entre los tratamientos, al 1 por ciento del nivel de probabilidad. No obstante, se observó una reducción en la producción cuando se comparó el tratamiento 1 con el 4, al 6 por ciento de probabilidad. Aparentemente, la cubierta plástica no tuvo efecto alguno en reducir el número de frutas dañadas debido al contacto con el suelo. Aunque el experimento se cosechó durante la época lluviosa, el número de frutas dañadas fue muy bajo y uniforme en todos los tratamientos. El hecho de que la interacción entre la variedad y el tratamiento, con relación al peso y número de frutas no fue significativa, indica que ninguna de las variedades usadas en este experimento respondió a tratamiento alguno, en particular. No obstante, se observó que fue la variedad Rutgers la que menos respondió respecto a los dos caracteres mencionados anteriormente. La cubierta de plástico negro aumentó la temperatura del suelo en 1°F., cuando se comparó con la del suelo al descubierto, a una profundidad de 2-4 pulgadas.
Título en español.
Authors: Conrado F. Asenjo  , Evangelina R. de Hernández  , Luz Divina Rodríguez  , Milka G. de Andino
Published: October 2020

Se determinaron mediante procedimientos químicos o microbiológicos los contenidos de ácido ascórbico, tiamina, riboflavina, niacina y ácido fólico de los jugos y néctares comerciales enlatados de albaricoque, toronja, guayaba, guayaba-piña, mango, china, papaya, melocotón, pera, piña, piña-china, guanábana, tamarindo y tomate. El contenido de vitamina del mismo producto y marca resultó estar, generalmente, en buen acuerdo, de lata a lata, en cuanto a riboflavina, tiamina y niacina. No estuvo tan de acuerdo en el caso de los ácidos ascórbico y fólico. El jugo de china demostró tener el contenido mayor de ácido ascórbico; el de tomate de riboflavina, niacina y ácido fólico, en ese orden respectivo, y el de piña de tiamina. Sin embargo, el contenido de tiamina del jugo de tomate fue un poco menor que el del jugo de piña. En general, los néctares tuvieron valores bien por debajo de los de los jugos; particularmente resultaron pobres en las vitaminas mencionadas los néctares de albaricoque, pera, melocotón, tamarindo y guanábana.
Título en español.
Authors: Raúl Pérez Escolar  , M. A. Lugo López
Published: October 2020

Los suelos Catalina y Cialitos difieren en su capacidad para el intercambio de cationes a pesar de que contienen cantidades similares de materia orgánica y arcilla. Las fracciones arcillosas de estos suelos se sometieron a exámenes con rayos X y a análisis térmicos diferenciales (DTA) para determinar si las diferencias en la capacidad de intercambio de cationes podían atribuirse a diferencias en la composición mineralógica de la fracción arcillosa. Los análisis revelaron que la caolinita predomina en dicha fracción en ambos casos. Sin embargo, se encontró que en la arcilla Cialitos la caolinita cristaliza pobremente, mientras que en la arcilla Catalina los cristales son bien definidos. Como se ha comprobado que mientras menos definida es la cristalización más alta es la capacidad de intercambio, se considera que esto podría explicar la razón por la cual la arcilla Cialitos posee una capacidad mayor de intercambio. Otro factor que puede explicar en parte la diferencia en capacidad de intercambio es el contenido de óxidos de hierro libres del suelo, que es mayor en el suelo Catalina arcilloso. Está comprobado que los óxidos de hierro libres bloquean las posiciones que normalmente ocuparían los cationes reemplazables en las arcilla caoliníticas.
BIRTH WEIGHT AND HEIGHT AT THE WITHERS OF PUREBRED AND GRADE HOLSTEIN HEIFER CALVES OF THE AGRICULTURAL EXPERIMENT STATION HERD
Authors: Manuel Soldevila  , Blas Salas Herrero
Published: October 2020

BIRTH WEIGHT AND HEIGHT AT THE WITHERS OF PUREBRED AND GRADE HOLSTEIN HEIFER CALVES OF THE AGRICULTURAL EXPERIMENT STATION HERD
Título en español.
Authors: Reinaldo Calero  , Parimal Choudbury  , George E. Pringle
Published: October 2020

Las relaciones en la estructura de la demanda y la oferta de trabajo se estimaron en la fase agrícola de la industria azucarera. El análisis se basó en series cronológicas que cubrían el periodo comprendido entre 1950-51 y 1965-66. Para calcular los parámetros en dichas estructuras se utilizó un modelo de regresión múltiple lineal, ya que los datos se ajustaban bastante bien a esta forma de ecuación. La demanda de trabajo en ese sector de la industria se expresa como una función de: 1, El área total de caña bajo cultivo, 2, productividad hombre-día por tonelada de caña, y 3, jornal promedio que se paga anualmente en esta empresa, El coeficiente de determinación explica el 89 por ciento de la variación (R2 = 0.8908) anual en la demanda de trabajo. Según la ecuación obtenida, un acre de caña está directamente asociada con 16.23 hombres-días en la demanda de trabajo. En dirección contraria, un aumento de una 0.10 toneladas de caña en la productividad hombre-día y de un dólar en el jornal promedio que se paga por el trabajo agrícola, tienden a reducir la demanda de trabajo en 902,800 hombres-días y 1,809,500 hombres-días, respectivamente. Por otro lado, la oferta de trabajo en ese mismo sector de la industria se expresa coma una función de: 1, El jornal promedio que se paga anualmente por trabajo agrícola, 2, cambios en la población, y 3, el periodo de tiempo. Estos tres factores explican alrededor del 96 por ciento de la variación (R2 = 0.956) anual en la oferta de trabajo. La ecuación de regresión indica que, un aumento de un dólar en el jornal promedio que se paga por trabajo agrícola y de una unidad de cambio en el índice de población, están asociados con un incremento de 845,000 hombres-días y de 367,000 hombres-días, respectivamente, en los recursos humanos disponibles en esa fase de a industria. Pero, por cada año que transcurre la cantidad de trabajo humano disponible está asociada con una reducción de 1,607,000 hombres-días.
EFFECT OF y IRRADIATION ON LEMON OIL AND LEMON-GRASS OIL
Authors: Owen H. Wheeler  , Elba Díaz de Osborne
Published: October 2020

EFFECT OF y IRRADIATION ON LEMON OIL AND LEMON-GRASS OIL
Título en español.
Authors: Frank W. Fisk  , Rafael Pérez Pérez
Published: October 2020

1. Durante cuatro noches consecutivas completas se observaron las actividades de vuelo de la mariposa nocturna, adulto del barrenador de la caña de azúcar, para las cuales se usaron trampas que alojaban mariposas hembras como señuelo y trampas con luz negra, en los campos de caña infestados por este insecto. 2. Los adultos machos se atraparon desde las 8 p.m. hasta las 4 a.m., registrándose dos apogeos de vuelo, uno temprano y otro tardío. Así, la población de estos adultos en Puerto Rico difiere en sus hábitos de vuelo de los de la misma especie en Louisiana. 3. Las trampas de luz negra atraparon adultos hembras del barrenador de la caña de azúcar sólo durante las noches obscuras con poca o ninguna luz lunar, mientras que los adultos machos pudieron atraparse en mayor número y en las mismas trampas en las noches luminosas. Las trampas con adultos hembras como señuelo fueron igualmente efectivas tanto en las noches obscuras como en las claras. 4. La hora en que se capturaron los adultos en las trampas de luz varió de la hora en que se capturaron los adultos machos, registrándose sólo un apogeo de vuelo temprano en la noche. 5. La experiencia actual en cuanto al método de construir y preparar señuelos en las trampas de lata y en las de luz y de localizarlas en el campo indica que es necesario mejorar este método antes de que pueda hacerse un estudio más eficiente y confiable de la población de adultos del barrenador de la caña de azúcar en Puerto Rico.
Título en español.
Authors: Raúl Pérez Escolar  , M. A. Lugo López
Published: October 2020

En este estudio se presentan datos sobre la humedad disponible en el suelo Catalina arcilloso, un Oxisol, y en el Cialitos arcilloso, un Ultisol. Ambos suelos tienen un contenido de arcilla sumamente alto y uno de materia orgánica bastante alto. El suelo Catalina arcilloso es alto en óxidos de hierro libres alcanzando un nivel de 18.2 por ciento, mientras que en el Cialitos éstos sólo alcanzan un 13 por ciento. Ambos suelos tienen una baja capacidad para suministrar el agua en estado disponible. Sin embargo, cuando se toman en cuenta los agregados individualmente, se observa que los más pequeños retienen un volumen mayor de agua disponible que los más grandes. Esto es así, porque la humedad retenida a tensiones altas decrece cuando disminuye el tamaño de los agregados, mientras que la retenida a tensiones bajas aumenta cuando disminuye el tamaño de los agregados. Los resultados se atribuyen al hecho de que los agregados grandes tienen un volumen mayor de poros pequeños, mientras que entre los agregados pequeños se forman poros más grandes.
COMPARISON OF GROWTH AND DEVELOPMENT OF SUGARCANE BORER LARVAE FROM PUERTO RICO AND LOUISIANA
Authors: S. D. Hensley  , L. F. Martorell
Published: October 2020

COMPARISON OF GROWTH AND DEVELOPMENT OF SUGARCANE BORER LARVAE FROM PUERTO RICO AND LOUISIANA
Field Losses of Coffee and Improved Harvesting Methods for Intensively Managed Plantations
Authors: Silva Servando , Vicente-Chandler José , Abruña Fernando
Published: October 2020

Total field losses of coffee beans in four 8- to 10-year-old intensively-managed commercial plantations consistently yielding over 1,500 pounds of picked market coffee per acre, averaged 931 pounds of market coffee worth over $600 per acre during the 1967 and 1968 crop years. An average of 12 percent of the total ripe berries produced are lost by dropping to the ground during actual picking operations. Strips of plastic netting laid on the ground under the trees during harvesting could recover this coffee (over 200 pounds of a 2,000-pound crop) with a net benefit to the farmer of about $87 per acre yearly. Laborers harvested about 50 percent more coffee by dislodging ripe berries to fall on netting laid on the ground than by the usual method of placing picked berries in baskets tied to their waists. This simple method could increase the pickers' income and reduce losses of beans falling to the ground during picking. It would also reduce losses of coffee due to labor shortages during critical periods in the picking season by increasing the efficiency of the available laborers.
RAPID DRYING OF PARCHMENT COFFEE IN UNSTIRRED BINS
Authors: Van Rest D. J.
Published: October 2020

RAPID DRYING OF PARCHMENT COFFEE IN UNSTIRRED BINS
Effect of Several Heat Treatments on Quality and Shelf life of a Frozen Guava Nectar Base
Authors: Sánchez Nieva F. , Hernández I. , Bueso de Viñas C.
Published: October 2020

Studies were conducted concerning the effect of several heat treatments on the quality and shelf-life of a frozen guava nectar base prepared from wild fruit. Heating nectar bases to 150°, 185° and 210° to 215° F., followed by rapid cooling and chilling, had no apparent effect on quality and shelflife. No appreciable changes were observed in acidity and reducing-sugars over a storage period of 400 days at —10° F. Insignificant changes in color occurred in plain tin and fully-enameled containers, even when F. D. C. Red No. 2 colorant was added to improve the color. Vitamin C retention during storage ranged from 89.0 to 97.8 percent. Vitamin C retention was observed higher than 100 percent in the samples canned in plain tin containers, attributed to formation of reducing interfering substances. Addition of vitamin C in levels ranging from 94 to 623 mg. per 100 g. of base had no effect on vitamin C retention. Heat treatments reduced bacterial and yeast counts. Because the several heat treatments tested had no appreciable effect on quality and shelf-life, the product may be packed without heat treatment in commercial practice or may be pasteurized by heating above 185° F. to reduce microorganism counts.
The Effect of Various Herbicides on Growth of Dioscorea composita (Hemsl.) Under Greenhouse Conditions
Authors: González-Ibáñez Jaime , Cibes-Viadé Héctor R.
Published: October 2020

A series of tests was conducted under greenhouse conditions to determine the relative usefulness of various herbicides for control of weeds in cortisone yam (Dioscorea composita Hemsl.) plantings. Monuron, Diuron, Neburon, Atrazine, Simazine and Prometryne each were applied at three different rates. Diuron and Monuron were found to be the most toxic of the substituted ureas. The most injurious of the triazines was Atrazine. Simazine, although somewhat toxic, was less so than than Atrazine. No evidence of Prometryne poisoning could be detected. As expected, the number and weight of weeds were significantly lower in the test plots of plants treated with herbicides.