Recommendation Systems: A Systematic Review

This article presents a comprehensive and objective systematic review of existing research on recommendation systems with regards to core theory, latest studies, various applications, current attitudes, and potential future applications. The research is mainly based on exploring professional peer-reviewed studies and articles and using their abstracts to create a comprehensive and unbiased review of existing research. The following search terms were used to identify articles and studies for the research: recommendation systems; recommender systems; core theory of recommender systems; current attitudes towards recommendation systems; latest studies on recommendation systems; applications of recommendation systems; potential studies on recommendation systems; and future potential applications of recommendation systems. The research also used the advanced search filter to locate recent studies for comparison by limiting the search by year to find studies published from 2021 onwards. Most literature on this area highlights the importance of recommendation systems in almost all aspects of modern life. Specifically, recommendation systems have become critical components in business, health care, education, marketing, and social networking domains. Additionally, most studies identified reinforcement of learning and deep learning techniques as significant developments in the field. These techniques form the backbone of most modern recommendation systems. The primary concern that could hinder further evolution systems is their consequent filter bubble effects which many studies showed to be problematic. Healthcare is a central area that shows tremendous potential for these systems. Although recommender systems have been implemented in this domain, there remains a lot of untapped potential that, if unleashed, could revolutionize medicine and healthcare. But the problems facing these systems have to be tackled first to establish trust. Keywords: Recommendation systems, Recommender systems, Deep learning, Reinforcement learning DOI: 10.7176/CEIS/13-4-04 Publication date:August 31st 202

TẠO DÒNG GEN MÃ HÓA CHITINASE 42 kDa CỦA TRICHODERMA ASPERELLUM VÀ DỰ ĐOÁN ĐẶC TÍNH CỦA ENZYME

Chitinase is an enzyme that catalyzes the hydrolytic reaction of chitin by cleaving 1,4-N-acetyl-β-glucosaminide linkages. Chitinase has been widely used in various fields, especially pest control, pollution reduction, and basic and applied biology. Chitinase from microorganisms is an essential source, typically from Trichoderma. After removing intron sequences, the gene encoding chitinase 42 kDa (chi42) from Trichoderma asperellum SH16 was synthesized and cloned into the pUC19 vector. The gene chi42 digested by BamHI and SacI was successfully cloned into the pQE30 vector, which was expressed in E. coli. The primary in silico analysis of the protein structure shows that chitinase is an extracellular protein. The secondary structure analysis reveals that chitinase has 15 α helices and 13 β sheets, while the dimension structure of chitinase is highly homological with the chitin hydrolytic enzyme from T. harzianum. The chitinase from T. asperellum is resistant to temperatures higher than 65 °C and exhibits acidic catalysis activity. Our results would provide basic information for heterologous expression and scale-up production of chitinase 42 kDa.Chitinase là enzyme xúc tác thủy phân chitin bằng cách phân cắt liên kết 1,4-N-acetyl-β-glucosaminide. Chitinase được ứng dụng rộng rãi trong nhiều lĩnh vực khác nhau, đặc biệt trong kiểm soát dịch bệnh, giảm thiểu ô nhiễm, nghiên cứu sinh học cơ bản và ứng dụng. Nguồn thu nhận chitinase chủ yếu là từ vi sinh vật, điển hình từ các chủng nấm Trichoderma. Gen mã hóa chitinase 42 kDa (chi42) của Trichoderma asperellum SH16 sau khi tạo dòng vào vector pUC19 được ghép nối thành công vào vector pQE30 để biểu hiện ở E. coli M15. Chitinase là enzyme ngoại bào. Cấu trúc bậc 2 của chitinase bao gồm 15 chuỗi xoắn α và 13 phiến β với cấu trúc không gian tương đồng cao với enzyme thủy phân chitin ở T. harzianum. Chitinase có khả năng chịu nhiệt độ cao hơn 65 °C và hoạt tính xúc tác mang tính acid. Kết quả nghiên cứu là cơ sở cho các nghiên cứu biểu hiện và sản xuất enzyme tái tổ hợp

PERCEPTIONS OF ENGLISH-MAJORED STUDENTS IN THE HIGH-QUALITY PROGRAM AT CAN THO UNIVERSITY TOWARD LEARNING ENGLISH THROUGH WATCHING MOVIES

This descriptive study aims to answer three main research questions, namely 1) What are the perceptions of English-majored students regarding the impact of watching English movies on their learning motivation?, 2) What are their perceptions of the impact of watching English movies on their language development?, and 3) What challenges do the students encounter when learning English through watching movies? In order to address these key questions, the data collected from 175 freshmen and juniors majoring in English Studies of the High-Quality Program at Can Tho University through a 5-point Likert scale questionnaire were quantitatively analyzed. The statistical analysis of the gathered data revealed that all the study participants strongly agreed with the positive impacts of watching English movies on their motivations to learn the target language as well as on their language development. Despite these positive effects, the students also admitted that they inevitably encountered several challenges while learning English through movie-watching, particularly in terms of rapid speech, extensive use of slang, and figurative language in English movies. Based on these research outcomes, possible implications have been further discussed for the effective use of movies in EFL classrooms to support the students’ learning process.  Article visualizations

Respiratory viruses in individuals with a high frequency of animal exposure in southern and highland Vietnam

Active surveillance for zoonotic respiratory viruses is essential to inform the development of appropriate interventions and outbreak responses. Here we target individuals with a high frequency of animal exposure in Vietnam. Three-year community-based surveillance was conducted in Vietnam during 2013-2016. We enrolled a total of 581 individuals (animal-raising farmers, slaughterers, animal-health workers, and rat traders), and utilized reverse transcription-polymerase chain reaction to detect 15 common respiratory viruses in pooled nasal-throat swabs collected at baseline or acute respiratory disease episodes. A respiratory virus was detected in 7.9% (58 of 732) of baseline samples, and 17.7% (136 of 770) of disease episode samples (P <.001), with enteroviruses (EVs), rhinoviruses and influenza A virus being the predominant viruses detected. There were temporal and spatial fluctuations in the frequencies of the detected viruses over the study period, for example, EVs and influenza A viruses were more often detected during rainy seasons. We reported the detection of common respiratory viruses in individuals with a high frequency of animal exposure in Vietnam, an emerging infectious disease hotspot. The results show the value of baseline/control sampling in delineating the causative relationships and have revealed important insights into the ecological aspects of EVs, rhinoviruses and influenza A and their contributions to the burden posed by respiratory infections in Vietnam.Peer reviewe

Some chemical constituents isolated from Acorus tatarinowii Shott.

Anew 8,1′-neolignan, tatarinone, 4-[2-(1,2,3-trimethoxybenz-5-yl)-1-methylethyl]-2,5-dimethoxy-4-(2-propenyl)-2,5-cyclohexadien-1-one, has been isolated from Acorus tatarinowii rhizome and  its structure determined by spectroscopic methods, including 2D-NMR spectra. Asarylaldehyde and a mixture of α-asarone and β-asarone were also isolated and  indentified.Keywords: Acorus tatarinowii;Araceae; 8,1′-neolignans; asarylaldehyde; α-asarone; β-asarone; NMR

Child stunting is associated with child, maternal, and environmental factors in Vietnam

Child stunting in Vietnam has reduced substantially since the turn of the century but has remained relatively high for several years. We analysed data on children 6–59 months (n = 85,932) from the Vietnam Nutritional Surveillance System, a nationally representative cross‐sectional survey. Multivariable Poisson regression models were used to estimate relative risk (RR) of stunting, stratified by child age and ecological region. Covariates at the child, maternal, household, and environmental levels were included based on available data and the World Health Organization conceptual framework on child stunting. Among children 6–23 months, the strongest associations with child stunting were child age in years (RR: 2.49; 95% CI [2.26, 2.73]), maternal height < 145 cm compared with ≥150 cm (RR: 2.04; 95% CI [1.85, 2.26]), living in the Northeast compared with the Southeast (RR: 2.01; 95% CI [1.69, 2.39]), no maternal education compared with a graduate education (RR: 1.77; 95% CI, [1.44, 2.16]), and birthweight < 2,500 g (RR: 1.75; 95% CI [1.55, 1.98]). For children 24–59 months, the strongest associations with child stunting were no maternal education compared with a graduate education (RR: 2.07; 95% CI [1.79, 2.40]), living in the Northeast compared with the Southeast (RR: 1.94; 95% CI [1.74, 2.16]), and maternal height < 145 cm compared with ≥150 cm (RR: 1.81; 95% CI [1.69, 1.94]). Targeted approaches that address the strongest stunting determinants among vulnerable populations are needed and discussed. Multifaceted approaches outside the health sector are also needed to reduce inequalities in socioeconomic status.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151838/1/mcn12826.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151838/2/mcn12826_am.pd

Evaluation of the Luminex xTAG Respiratory Viral Panel FAST v2 assay for detection of multiple respiratory viral pathogens in nasal and throat swabs in Vietnam.

BACKGROUND: Acute respiratory infections (ARI) are among the leading causes of hospitalization in children ≤5 years old. Rapid diagnostics of viral pathogens is essential to avoid unnecessary antibiotic treatment, thereby slowing down antibiotic-resistance. We evaluated the diagnostic performance of the Luminex xTAG Respiratory Viral Panel FAST v2 against viral specific PCR as reference assays for ARI in Vietnam. METHODS: Four hundred and forty two nose and throat swabs were collected in viral transport medium, and were tested with Luminex xTAG Respiratory Viral Panel FAST v2. Multiplex RT-PCR and single RT-PCR were used as references.    Results: Overall, viral pathogens were detected in a total count of 270/294 (91.8%, 95% CI 88.1-94.7) by the Luminex among reference assays, whilst 112/6336 (1.8%, 95% CI, 1.4-2.1) of pathogens were detected by the Luminex, but not by reference assays. Frequency of pathogens detected by Luminex and reference assays was 379 and 292, respectively. The diagnostic yield was 66.7% (295/442, 95%CI 62.1-71.1%) for the Luminex assay and 54.1% (239/442, 95% CI, 49.3-58.8%) for reference assays. The Luminex kit had higher yields for all viruses except influenza B virus, respiratory syncytial virus, and human bocavirus. High agreements between both methods [mean (range): 0.91 (0.83-1.00)] were found for 10/15 viral agents. CONCLUSIONS: The Luminex assay is a high throughput multiplex platform for rapid detection of common viral pathogens causing ARI. Although the current high cost may prevent Luminex assays from being widely used, especially in limited resource settings where ARI are felt most, its introduction in clinical diagnostics may help reduce unnecessary use of antibiotic prescription

Antibiotic use and prescription and its effects on Enterobacteriaceae in the gut in children with mild respiratory infections in Ho Chi Minh City, Vietnam. A prospective observational outpatient study.

BACKGROUND AND OBJECTIVES: Treatment guidelines do not recommend antibiotic use for acute respiratory infections (ARI), except for streptococcal pharyngitis/tonsillitis and pneumonia. However, antibiotics are prescribed frequently for children with ARI, often in absence of evidence for bacterial infection. The objectives of this study were 1) to assess the appropriateness of antibiotic prescriptions for mild ARI in paediatric outpatients in relation to available guidelines and detected pathogens, 2) to assess antibiotic use on presentation using questionnaires and detection in urine 3) to assess the carriage rates and proportions of resistant intestinal Enterobacteriaceae before, during and after consultation. MATERIALS AND METHODS: Patients were prospectively enrolled in Children's Hospital 1, Ho Chi Minh City, Vietnam and diagnoses, prescribed therapy and outcome were recorded on first visit and on follow-up after 7 days. Respiratory bacterial and viral pathogens were detected using molecular assays. Antibiotic use before presentation was assessed using questionnaires and urine HPLC. The impact of antibiotic usage on intestinal Enterobacteriaceae was assessed with semi-quantitative culture on agar with and without antibiotics on presentation and after 7 and 28 days. RESULTS: A total of 563 patients were enrolled between February 2009 and February 2010. Antibiotics were prescribed for all except 2 of 563 patients. The majority were 2nd and 3rd generation oral cephalosporins and amoxicillin with or without clavulanic acid. Respiratory viruses were detected in respiratory specimens of 72.5% of patients. Antibiotic use was considered inappropriate in 90.1% and 67.5%, based on guidelines and detected pathogens, respectively. On presentation parents reported antibiotic use for 22% of patients, 41% of parents did not know and 37% denied antibiotic use. Among these three groups, six commonly used antibiotics were detected with HPLC in patients' urine in 49%, 40% and 14%, respectively. Temporary selection of 3rd generation cephalosporin resistant intestinal Enterobacteriaceae during antibiotic use was observed, with co-selection of resistance to aminoglycosides and fluoroquinolones. CONCLUSIONS: We report overuse and overprescription of antibiotics for uncomplicated ARI with selection of resistant intestinal Enterobacteriaceae, posing a risk for community transmission and persistence in a setting of a highly granular healthcare system and unrestricted access to antibiotics through private pharmacies. REGISTRATION: This study was registered at the International Standard Randomised Controlled Trials Number registry under number ISRCTN32862422: http://www.isrctn.com/ISRCTN32862422

Primary Care Influenza-like Illness Surveillance in Ho Chi Minh City, Vietnam 2013-2015

BACKGROUND: Year-round transmission of influenza has been detected in Vietnam through both national surveillance and other epidemiological studies. Understanding the demographic and clinical features of influenza-like-illness (ILI) presenting to primary care in urban Vietnam is vital to understand these transmission dynamics. METHODS: A prospective, observational study of patients with ILI in Ho Chi Minh City, Vietnam was conducted between August 2013 and November 2015 in a mix of public and private primary care settings. Molecular testing for Influenza A & B and 12 other respiratory viruses was performed. RESULTS: 1152 ILI patients were recruited. 322 and 136 subjects tested positive for influenza A and B, respectively. 193 subjects tested positive for another respiratory virus; most commonly rhinovirus and parainfluenza virus 3. Influenza was detected in 81% of the 116 study weeks. Three peaks of influenza activity were detected; an H3N2 peak April-June 2014, an influenza B peak July-December 2014, and a mixed H3N2 and H1N1 peak March-September 2015. Subjects recruited from private clinics were more likely to have higher income, and to have reported previous influenza vaccination. Antibiotic use was common (50.3%) despite limited evidence of bacterial infection. CONCLUSION: Influenza in southern Vietnam has complex transmission dynamics including periods of intense influenza activity of alternating types and subtypes. Broadening surveillance from hospital to the community in tropical settings is feasible and a valuable for improving our understanding of the global spread and evolution of the virus. This article is protected by copyright. All rights reserved