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The paper presented two X-ray fluorescence analysis methods applicable to element content analysis in mixed fertilizers. The applied addition method determined the content of each ingredient in the fertilizer. The fundamental parameter method was applied for quick analysis, and at the same time, the content of ingredients on the fertilizer production line. X-ray fluorescence analysis methods and equipment have been researched and developed by the Institute of Materials Science - Vietnam Academy of Science and Technology and put into the gold and silver field for more than 30 years. The machines fabricated after 2014 applied TCVN 7055:2014, the 2nd edition "gold and gold alloys – Determination of gold content by X-ray fluorescence method". The national gold standard sample set, managed by the Vietnam Metrology Institute, was used to calibrate the machine, which has standard association with NIST (USA) and Krastsvetmet (Russia). Up to now, there are nearly 100 machines operating in more than twenty provinces and cities across the country, used to check the content of alloying components in gold jewelry processing, production and trading. The aim of new research and development in the field of fertilizers, in the coming time, is to transfer equipment and analysis methods to fertilizer production and trading enterprises.

Objectives Open reduction and internal fixation of both columns is considered the treatment of choice for displaced anterior column with posterior hemitransverse (ACPHT) fractures in non-geriatric patients. Plate fixation of one column combined with lag screw fixation of the other column allows to decrease operative time and approach-related morbidity compared to conventional both column plating. The aim of this biomechanical study was to evaluate whether single column plate plus other column lag screw fixation confers similar stability to both column plate fixation. Physiological loads were simulated using both the single-leg stance (SLS) as well as the sit-to-stand (STS) loading protocols. Methods A clinically relevant ACPHT fracture model was created using fourth-generation composite hemipelves. Fractures were stabilized with three different fixation constructs: (1) anterior column plate plus posterior column screw fixation (AP+PCS), posterior column plate plus anterior column screw fixation (PP+ACS) and anterior column plate plus posterior column plate fixation (AP+PP). Specimens were loaded from 50 to 750 N with a ramp of 100 N/s. Fracture gap motion (FGM) and relative interfragmentary rotation (RIFR) between the three main fracture fragments were assessed under loads of 750 N using an optical 3D measurement system. Results STS loading generally resulted in higher mean FGM and RIFR than STS loading in the AP+PCS and AP+PP groups, while no significant differences were found in the PP+ACS group. Compared to conventional both column plate fixation (AP+PP), PP+ACS displayed significantly higher FGM and RIFR between the iliac wing and the posterior column during SLS loading. No significant differences in FGM and RIFR were identified between the AP+PCS and the AP+PP group. Conclusion Overall, single column plate plus other column lag screw fixation conferred similar stability to conventional both column plate fixation. From a clinical point of view, AP+PCS appears to be the most attractive alternative to conventional AP+PP for internal fixation of ACPHT fractures.

PurposeThe purpose of this paper is to investigate the incidence and earning effects of the vertical mismatch between attained and required educational qualifications in a developing country’s labor market.Design/methodology/approachFollowing Duncan and Hoffman (1981), this paper uses the augmented Mincerian wage equation to decompose the actual years of education of a person into years of over-education, years of required education and years of under-education. These years of education are then fitted in an ordinary least squares model to measure the earning effects of an employee when his/her attained educational qualifications are higher or lower than the required educational level in his/her job.FindingsUnlike studies in developed countries, this paper finds that Vietnam has a higher incidence of under-education than over-education due to a large proportion of the population in rural and remote areas not having access to formal education. Further, qualification mismatch has an asymmetric effect on earnings in the sense that the wage rate is flexible downward but rigid upward. In particular, years of schooling that are in excess or in deficit of the required level for the job are not compensated with higher earnings. This paper concludes that although qualification mismatch incidence in Vietnam is different from that in developed countries, mismatched workers also suffer from significant wage penalty.Originality/valueThis paper makes a significant contribution by providing the first evidence from a developing country to the vertical mismatch literature which has already been overwhelmed with studies from advanced economies.

Objectives To biomechanically compare five different fixation techniques for transverse acetabular fractures using both the single-leg stance (SLS) and the sit-to-stand (STS) loading protocols and to directly compare fracture gap motion (FGM) and relative interfragmentary rotation (RIFR). Methods Transtectal transverse acetabular fractures were created on fourth-generation composite hemipelves in a reproducible manner. Five different fixation techniques were biomechanically assessed using both an SLS and STS loading protocol: anterior plate (AP) only, posterior plate (PP) only, anterior plate plus posterior column screw (AP+PCS), posterior plate plus anterior column screw (PP+ACS) and anterior plus posterior plate (AP+PP). After preconditioning, the specimens were loaded from 50 to 750 N with a ramp of 100 N/s. FGM and RIFR under loads of 750 N were measured using an optical 3D measurement system. Results In the three groups of fixation techniques addressing both columns, STS loading resulted in higher mean FGM and in RIFR than SLS loading. No construct failure was observed. In the single plate groups (AP only and PP only), STS loading resulted in failure of all specimens before reaching loads of 750 N, while no failure occurred after SLS loading. No significant differences in FGM and RIFR were found between the double plate (AP+PP) and the single plate plus column screw (AP+PCS and PP+ACS) techniques. Conclusion SLS loading appeared to overestimate the strength of acetabular fracture fixation constructs and STS loading may be more appropriate to provide clinically relevant biomechanical data. Internal fixation of a single column might not provide adequate stability for transverse fractures, while strength of single plate plus column screw fixation and double plate fixation was comparable.

Nghiên cứu nhằm khám phá các nhân tố tác động đến việc thu hút vốn đầu tư vào tỉnh Quảng Trị, bằng việc khảo sát 109 nhà đầu tư hiện hữu tại tỉnh và nhà đầu tư dự định đầu tư vào tỉnh. Thang đo điều chỉnh từ thang đo đầu tư của Toàn (2010), cùng với phương pháp phân tích độ tin cậy Cronbach’s Alpha, phân tích nhân tố khám phá (EFA).Kết quả cho thấy có 9 nhóm nhân tố tác động đến việc thu hút vốn đầu tư vào tỉnh Quảng Trị, trong đó 5 nhân tố được đánh giá trên mức trung bình: (1) Quá trình ra quyết định liên quan đến thủ tục đầu tư, (2) Chính sách hỗ trợ từ Cơ quan quản lý liên quan đến nhà đầu tư, (3) Cơ sở hạ tầng kỹ thuật, (4) Tài nguyên, (5) Cơ sở hạ tầng khu công nghiệp, khu kinh tế, và 4 nhân tố được đánh giá dưới mức trung bình: (6) Cơ sở hạ tầng xã hội, (7) Tiềm năng thị trường, (8) Lợi thế chi phí, (9) Năng suất và tính kỷ luật lao động

There is a need to examine the effect of using discussion cases to enrich students’ learning outcomes. A research framework was created to study this multidimensional relationship, via the instruments of interactivity, students’ time devotion and students’ engagement in order to find which factors could improve learning outcomes, including positive group interaction and individual learning performance. The findings from three cohorts of undergraduate students of the same course indicated that interactivity with peers and with the lecturers during the case discussion in classes improved emotional engagement, which in turn positively influenced positive group interaction and individual learning performance. The study also found that students’ emotional engagement was a significant factor in enriching outcomes. Although there was a lack of direct impact of interactivity on learning outcomes, there were many reasons attributed to it. The time that students devoted to the task, as a result of interactivity with the lecturer, was a significant predictor of emotional academic engagement, but it did not predict desirable learning outcomes.

The study focused on the orientations of building sustainable new rural areas associated with urbanization. This was very necessary, in order to develop a concentrated, commodity agriculture and to form residential areas and infrastructure, which were suitable to the process of industrialization and modernization of agriculture and rural areas. The agricultural sector was restructured, and the living conditions of rural people were improved close to those in urban areas. The project of the National Target Program on building new rural areas in Vietnam was analyzed. The program has achieved many expected results. In which, the construction of new rural areas has achieved great achievements. The basic socioeconomic infrastructure in the rural areas was strengthened in a synchronous direction. The sustainable development of the rural economy was in the direction of increasing added values and raised people’s incomes and gradually narrowed the gap between rural and urban areas. The work of landscape construction, implementation of environmental sanitation had a remarkable change.