bluuebunny/crossref_metadata_2025 huggingface dataset:
A cross-sectional study to assess acute malnutrition among under-5 children in the field practise area of a teaching hospital in Chennai
Authors: Naresh Sulekha , Maiya G. Rakesh
Published: January 2021

Context:

Malnutrition is one of the leading problem mainly in childhood, affecting growth and development especially under 5 years of age. According to NFHS-4, under-5 children about 27% are stunted, 20% are wasted and 24% are underweight. Determining acute malnutrition (wasting) and its factors is necessary to prevent complications.

Aims:

To assess acute malnutrition among under 5 years children and determine associated factors responsible.

Settings and Design:

Cross-sectional study done at field practice area under a teaching hospital in Chennai.

Materials and Methods:

Totally, 149 children under 5 years of age were selected and assessed for acute malnutrition using WHO standards (Z-scoring) by calculating weight for height. Questionnaire for checking associated factors was used.

Statistical Analysis Used:

Data were entered in excel spreadsheet and analyzed using SPSS software version 16 and for inferential statistical analysis was done using Chi square test.

Result:

Among the study population, 87.2% children were normal, 10% of children had wasting (below -2 S.D.) and 2.8% of children had severe wasting (below -3 S.D.). Wasting was also prevalent among people of low socioeconomic class and was maximum in children of age group 1-3 years. Low birth weight, absence of exclusive breast feeding and complementary feeding practices, partial immunization and other illnesses also had effect, leading to acute malnutrition.

Conclusion:

Level of acute malnutrition in the field practice area is lesser than the national average and determines few factors associated with malnutrition among under – 5 children.
A study on smartphone addiction and its effects on sleep quality among nursing students in a municipality town of West Bengal
Authors: Ghosh Trishan , Sarkar Deblina , Sarkar Kingsuk , Dalai Chanchal Kumar , Ghosal Arnab
Published: January 2021

Background:

Smartphones are now an important gadget for us, but the many are getting addicted to it. Researchers showed that smartphone addiction and late-night usage affects sleep quality. Indian nurses are already facing a heavy burden of depression and present position of nurses is quite insecure. Very few studies were performed over nursing students and that leads to the selection of this topic for my research.

Methodology:

It was a cross-sectional, observational, and questionnaire-based study, performed over B.Sc. Nursing students of University College of Nursing, WBUHS. The questionnaire has three parts. The first part was for sociodemographic variables, the second part measures the addictive phenomena associated with smartphone overuse using a Smartphone Addiction Scale (SAS), the last part was intended to measure the sleep quality by using Pittsburgh Sleep Quality Index (PSQI). Collected data was compiled and analyzed with the help of MS-Excel from Microsoft Office Package-2016.

Results:

Out of 91 students, 46 students were found to be not addicted, while 45 were addicted to smartphone, as measured by SAS. On PSQI, 17.58% students were found to be good sleepers, while 82.42% came out to be poor sleepers. Significant association was found between age and smartphone addiction (p=0.000031) and between daily calls and sleep quality (p=0.025333).

Conclusion:

It can be finally concluded that increase in smartphone usage is now a serious matter of concern and lower age groups are more susceptible towards it. Broad-spectrum studies involving multiple institutions is needed to reveal the bigger picture
Significant physiological impact of wearing PPE inside operation theatre
Authors: Yunus Md. , Deb Prakash , Das Rituparna , Bhattacharyya Prithwis
Published: January 2021

Owing to COVID-19 pandemic, wearing personal protective equipment (PPE) and N95 mask inside an operation theatre has become a common practice. Subjective symptoms of suffocation, headache, dizziness, and lack of concentration while on PPE may at times become significant enough requiring oxygen therapy, removal of mask, or even doffing of PPE, which may increase the risk of being infected and at the same time compromising patient care. The reason behind such subjective symptoms may be multifactorial. We report here a 52-years-old anesthetist with a high body mass index, wearing PPE for a prolonged duration inside an operation theatre during a high-risk surgery encountered a similar episode. Being the lone anesthetist, he decided to oxygenate himself in an innovative way, thus, avoiding doffing and any undesirable event. With pandemic expanding rapidly such scenarios may be encountered often, identifying factors predicting such events and finding methods of oxygenation while wearing PPE may be extremely beneficial.
Clinical spectrum and outcome of patients visiting coronavirus screening centre in North India and clinical predictors for COVID-19
Authors: Singla Neeraj , Gowda Rudresh , Mohindra Ritin , Suri Vikas , Dhibar Deba Prasad , Sharma Navneet
Published: January 2021

Aim:

The aim of this study is to elucidate the demographics, symptoms and outcome of sick persons visiting coronavirus (COVID) screening OPD of a tertiary institute in North India.

Study Design:

The present descriptive, prospective study was done on 1030 patients and information about presenting symptoms, demographics (age, sex, nationality, residence), contact and travel history, comorbidities etc., were recorded. On the basis of criteria given by Indian Council of Medical Research, patients were divided into suspected (SARS-CoV-2) and non-suspected group. Of the suspected patients, with RT-PCR test positive were classified as confirmed COVID-19 case and negative RT-PCR symptomatic individual were defined as negative COVID-19 case.

Results:

Out of the total patients, 65.6% were male and 34.4% were females. The mean age was 37.04 years. Fever 49.3%, cough 57.1% and sore throat 43.5% were the main symptoms. Comorbidities were seen in 8.5% patients with hypertension (3.5%) and diabetes mellitus (3.4%). Forty patients were positive. Highly significant correlation (P < 0.01) was found between COVID-19 positive status and in patients without any symptoms, between COVID-19 and cough and sore throat, between COVID-19 and comorbidity (diabetes mellitus), between COVID-19 and high-risk exposures (resident of hot spot and history of contact with confirmed case). Our study also found COVID-19 positive status, shortness of breath and tachycardia as independent predictors of mortality (P < 0.05).

Conclusions:

Most of the patients were young adults and males were mainly affected. Main presentation was cough followed by fever. Infectivity was higher in patients who had underlying comorbid diseases, especially diabetes and chronic kidney disease. Critical patients with decreased oxygen saturation, tachypnoea and tachycardia had strong predictability for COVID-19 positivity. COVID-19 positive status, shortness of breath and tachycardia are important predictors of mortality.
Frequent clinical and radiological manifestations of the Novel SARS-CoV-2
Authors: Alshoabi Sultan Abdulwadoud , Alhazmi Fahad H. , Abdulaal Osamah M. , Gameraddin Moawia B. , Algaberi Ali K. , Hamid Abdullgabbar M. , Alsultan Kamal D. , Alamri Abdulrahman M.
Published: January 2021

Coronavirus disease 2019 (COVID-19) is a highly infectious disease caused by the novel “severe acute respiratory syndrome coronavirus-2” (SARS-CoV-2) and is rapidly spreading worldwide. This review is designed to highlight the most common clinical features and computed tomography (CT) signs of patients with COVID-19 and to elaborate the most significant signs indicative of COVID-19 diagnosis. This review involved five original articles with both clinical and radiological features of COVID-19 published during Jan and Mar 2020. In this review, the most frequent symptoms of COVID-19 were fever and cough. Myalgia, fatigue, sore throat, headache, diarrhea, and dyspnea were less common manifestations. Nausea and vomiting were rare. Ground-glass opacity (GGO) was the most common radiological finding on CT, and mixed GGO with consolidation was reported in some cases. In addition, elevated C-reactive protein and lymphopenia are the pertinent laboratory findings of COVID-19. CT is an effective and important imaging tool for both diagnosis and follow-up COVID-19 patients with varied features, duration, and course of the disease. Bilateral GGOs, especially in the periphery of the lungs with or without consolidation, are the hallmark of COVID-19.
A clinical comparative study using anchorage from mini-implants and conventional anchorage methods to retract anterior teeth
Authors: Malhotra Abhita , Mangla Rajat , Dua Vinay S. , Kannan Sridhar , Arora Nitin , Singh Ashish Kumar
Published: January 2021

Background:

Proclined teeth has been one of the main reasons for compromised esthetics. In a patient with proclined anteriors, retraction is done after 1st premolar extraction. Absolute/maximum anchorage is required to achieve the best esthetics.

Objective:

We conducted this study with the aim of retracting the proclined maxillary anterior teeth and to check for efficient retraction, type of tooth movement during retraction, and amount of anchorage loss.

Methods:

Patients with proclined anterior teeth where therapeutic extraction of first premolars is required were included in the study, where anchorage was taken with mini-implants in one group, and in the second group, conventional anchorage method of 1st and 2nd molar banding with TPA was chosen. Each group consisted of 8 subjects. Lateral cephalogram was taken both preretraction and 4 months after starting retraction to compare anchor loss, rate of retraction, and type of tooth movement of retracted anteriors, in both groups.

Results:

The retraction in the implant group was more than in the conventional group and the difference was statistically significant (P < 0.05). Anchorage loss was seen to be greater in conventional group than in the implant group and was also significant statistically. The type of tooth movement of the anterior teeth on retraction was also compared, with the implant group showing predominantly controlled tipping and the conventional group showing uncontrolled tipping movement.
Role of Interleukin-7 in the Development of and Recovery from Radiation-Induced Lymphopenia: A Post-hoc Analysis of a Prospective Cohort
Authors: Byun Hwa Kyung , Chung Seung Yeun , Kim Kyoung-Jin , Seong Jinsil
Published: January 2021

Purpose Radiation-induced lymphopenia is associated with worse outcomes in solid tumors. We assessed the impact of interleukin-7 (IL-7), a key cytokine in lymphocyte homeostasis, on radiation-induced lymphopenia.Materials and Methods A post-hoc analysis was performed in a prospective cohort of 98 patients with hepatocellular carcinoma who were treated with radiotherapy in 2016-2018. Blood IL-7 levels were assayed before and at the end of radiotherapy. Acute severe lymphopenia (ASL) was defined as a total lymphocyte count of < 200/μL during radiotherapy. Cox and logistic regression analyses were performed to identify predictors of survival and ASL development, respectively.Results Patients with ASL (n=41) had significantly poorer overall survival than those without (12.0 months vs. 25.3 months, p=0.001). Patients with lymphocyte recovery showed significantly longer overall survival than those without (21.8 months vs. 10.3 months, p=0.042). ASL was an independent predictor of poor survival (hazard ratio, 2.07; p=0.015). Patients with ASL had significantly lower pre-radiotherapy IL-7 levels (2.07 pg/mL vs. 3.01 pg/mL, p=0.010). A high pre-radiotherapy IL-7 level was an independent predictor of a reduced risk of ASL development (hazard ratio, 0.40; p=0.004). IL-7 levels reflected a feedback response to ASL, with a higher ΔIL-7 in patients with ASL and a lower ΔIL-7 in those without ASL (0.48 pg/mL vs. –0.66 pg/mL, p < 0.001). Post-radiotherapy IL-7 levels were significantly positively correlated with the total lymphocyte counts at 2 months.Conclusion IL-7 is associated with the development of and recovery from ASL, which may impact survival. To overcome radiation-induced lymphopenia, a novel strategy using IL-7 may be considered.
Третья краевая задача в полуполосе для $B$-параболического
уравнения
Authors: Khushtova Fatima Gidovna
Published: January 2021

Исследуется третья краевая задача в полуполосе для дифференциального
уравнения в частных производных с оператором Бесселя. Доказаны теоремы
существования и единственности. Представление решения найдено
в терминах свертки Лапласа экспоненциальной функции и функции типа
Миттаг-Леффлера со степенными множителями. Единственность доказана
в классе ограниченных функций.
Библиография: 31 название.
Hepatocurative potentials of methanol extracts/fractions of Tapinanthus bangwensis and Moringa oleifera on carbon tetrachlorideinduced hepatotoxicity in Wistar rats
Authors: Ihegboro G.O. , Alhassan A.J. , Afor E. , Ononamadu C.J. , Owolarafe T.A. , Imam A.A. , Salawu K. , Ibrahim A. , Sule M.S.
Published: January 2021

Bioaccumulation of toxic substances in liver poses a serious threat to its functionality and consequently leads to damage/injury. Medicinal plants have been reported to be effective in the treatment and management of various diseases. The present study is aimed at evaluating the hepatocurative potentials of Tapinanthus bangwensis and Moringa oleifera on carbon tetrachloride-induced hepatotoxicity in Wistar rats. Atomic absorption spectroscopy (AAS) and ultraviolet-visible spectrophotometry were respectively used to assay for mineral elements and antioxidant activity of methanol extracts/fractions of T. bangwensis and M. oleifera. Concentrations of potassium in methanol extract of M. oleifera (MeCE 2) and magnesium in T. bangwensis (MeCE 1) were found to be significantly high (p < 0.05). Concentrations of trace elements were low in the range of 0.07 mg/kg to 0.60 mg/kg. The in vitro lipid peroxidation assay showed that ethylacetate fraction and acetone fraction of T. bangwensis (ETF 1 and ACF 1) respectively exhibited the strongest and lowest antioxidant activity compared to other extracts/fractions. Oral administration of methanol extracts/fractions of T. bangwensis and M. oleifera significantly increased superoxide dismutase (SOD) and catalase (CAT) activities, increased glutathione (GSH) level and decreased malondialdehyde (MDA) level. The liver function indices (or liver biomarkers) such as aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), albumin, total protein, total and conjugated bilirubin and lipid parameters (low density lipoprotein (LDL-c), cholesterol and triglyceride) were also significantly reduced. However high density lipoprotein (HDL-c) increased in the groups induced and treated with methanol extracts/fractions of T. bangwensis and M. oleifera compared to the group induced but untreated. It can be concluded that the plants possessed hepatocurative potential against CCl - 4 induced hepatotoxicity in Wistar rats

Keywords: Bioaccumulation, Hepatotoxicity, Liver biomarkers, Moringa oleifera Tapinanthus bangwensis
Comparison of performance characteristics of two malaria rapid diagnostic tests in detecting malaria infection among febrile patients in Urban Area of Lagos, Nigeria
Authors: Odeniyi O.M. , Agomo C.O. , Okangba C.C. , Olaniyan K.O. , Oyibo W.A.
Published: January 2021

Antigen-based malaria rapid diagnostic tests (mRDT) play an important role in confirmation of malaria cases in all levels of healthcare in Nigeria because they are fast, easy to perform, and do not require special equipment or electricity. This study aimed at assessing the performance of two mRDTs in detecting histidine-rich protein 2 antigen in blood and urine of persons with uncomplicated falciparum malaria. Malaria parasite microscopy was the malaria diagnosis gold standard in this study. Matched blood and urine samples from 1,026 febrile persons were tested with two commercially available malaria antigen-detecting kits (SD Bioline and First Response® ). Based on blood samples, similar malaria positivity rates were obtained by microscopy 181 (17.6%), SD Bioline 186 (18.1%) and First Response® 183 (17.8%). Detection of HRP2 antigens in urine was  significantly lower than  HRP2 detection in blood (P<0.001) regardless of brand of mRDT used [SD Bioline (5.2% vs 18.1%) and First  Response® (4.6% vs 17.8%)]. The performance characteristics of SD Bioline and First Response® using blood samples were similar (P>0.05): sensitivity 96.7% vs 95.0%; specificity 98.7% vs 98.7%, Positive Predictive  Value (PPV) 92.5% vs 94% and Negative Predictive Value (NPV) 99.3% vs 86.4%. SD Bioline and First  Response® HRP2 in urine and blood by the two kits was not dependent on the level of parasitaemia. The performance of the two brands of mRDTs in detecting HRP2 in whole blood and urine were similar (P>0.05). The two kits serve as good alternatives to malaria microscopy. The high NPV of both kits with urine specimen indicates that urine has the potential to be used for malaria but is not currently recommended to be used on blood-based malaria test kits.

Keywords: Histidine Rich Protein® 2, Malaria Rapid Diagnostic Test, Performance characteristics, Urine.
Antimicrobial activity and phytochemical screening of Adansonia digitata stem bark extract on some clinical isolates
Authors: Ajiboye A.E. , Sadiq S.O. , Adedayo M.R.
Published: January 2021

Adansonia digitata is a massive and deciduous tree with a height of about 24 m and of significant economic importance. The antimicrobial and  phytochemical screening of the aqueous and ethyl-acetate extract of stem bark of the plant were determined on some clinical isolates. The stem bark of the plant was collected and washed o properly before drying at 28 C. The pulverised stem bark was extracted with water and ethyl-acetate and screened for phytochemicals (qualitative and quantitative) using standard methods. The clinical isolates used were identified as Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli and Candida albicans. The antimicrobial activities of the crude extracts were carried out using the agar well diffusion methods. The minimum inhibitory concentration (MIC), minimum bactericidal and fungicidal concentrations were carried out using standard methods. The aqueous extract exhibited a higher zone of inhibition against S. aureus (14.00 ± 0.57 mm) at a concentration of 200 mg/ml while a zone of inhibition of 11.66±0.33 mm was observed for E. coli using ethylacetate extract. Candida albicans had a zone of inhibition of 11.66±0.88 mm and 11.00±0.57 mm using aqueous and ethyl-acetate extracts respectively at 200 mg/ml. The MIC was 200 mg/ml for the crude extracts against the clinical isolates. The qualitative ethyl-acetate phytochemical screening revealed the presence of phenol, flavonoids, tannins, alkaloids, saponin and terpenoids. Phenol had the highest concentration of 2.02±0.25 mg/ml while terpenoids had a value of 1.38±0.02 mg/ml. Aqueous and ethyl-acetate extract of A. digitata possess significant antimicrobial activity against E. coli, S. aureus and C. albicans. However, K. pneumoniae showed resistance to ethyl acetate extract.

Key words: Adansonia digitata, Antimicrobial activity, Clinical isolates, Phytochemical  screening
Adsorption of Fe , Pb , Zn and Cr ions from aqueous solutions using natural, ammonium oxalate and sodium hydroxide modified Kaolinite clay
Authors: Lawal J.A , Odebunmi E.O. , Adekola F.A.
Published: January 2021

In this paper, Fe2+ , Pb2+ , Zn2+ and Cr6+ ions removal from contaminated water with natural Nigerian kaolinite clay (AK-clay), and that removed with kaolinite clay modified with either ammonium oxalate (AK-AO) or sodium hydroxide (AK-S) were presented. The clay was characterized using X-Ray Diffractometry (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and Brunanuer-EmmettTeller (BET) method. The parameters investigated include pH, adsorbent particle size, shaking speed, metal ion concentration and temperature. The optimum conditions were applied to the modified samples. Design-expert software was used to design the experimental conditions using Response Surface Methodology (RSM). The mineralogical characterization showed the purified 63 µm fraction of the clay as kaolin. Analysis of Variance shows the adsorption of the metal ions was statistically significant with p-valves > 0.0001 at 95 % confidence limit. Pseudo second-order kinetic model was found to fit the adsorption data for all the metal ions. The  adsorption of Fe2+ , Pb2+ and Cr6+ ions was best described by the Langmuir isotherm model, while Freundlich  isotherm model best fitted the adsorption data for Zn2+ ion. Thermodynamic analysis of adsorption data shows the metal ions adsorption was spontaneous, endothermic and accompanied by positive entropy change.   Compared to unmodified natural clay, AK-S clay increased adsorption capacity for Fe2+ , Pb2+ , Zn 2+ and Cr 6+ ions from 14.1 to 18.425 mg/g, 18.4 to 19.8 mg/g, 16.875 to 19.9 mg/g and 7.65 to 8.15 mg/g respectively. The AK2+  AO2+ clay increased the uptake of Fe ion from 14.1 to 17.35 mg/g with a slight increase for Zn ion (16.875 to 16.95 mg/g). The adsorption capacity of AK-clay for all the metal ions was enhanced by NaOH modification 2+ while the ammonium oxalate modification significantly enhanced the adsorption capacity only for Fe ion. The results show that NaOH and ammonium oxalate modified kaolinite clay are effective for remediation of heavy metal-laden wastewater.

Keywords: Kaolinite, metal ions, adsorption, kinetics, adsorption isotherm
SIMULATION OF ODOUR DISPERSION FROM DA PHUOC LANDFILL
Authors: VĂN VIỆT LƯƠNG , HOÀNG ANH LÊ , DOÃN DUNG ĐỖ , VĂN VUI TRẦN
Published: January 2021

The purpose of this research is estimation rate of odorous gas emission from landfills and simulating the odour dispersion. The method used for the study was based on the methane emission model of Intergovermental Panel on Climate change and Gauss Model. The study results showed no discrepancies between calculated and measured data of odorous gas emission, Nash-Sutcliffe coefficient ranged from 0,642 to 0,770. The results of the odour intensity simulations show that there is no significant deviation from the actual data. The difference between the observation and the odor intensity simulation is usually less than one level.
ẢNH HƯỞNG CỦA NHỰA THÔNG ĐẾN TÍNH CHẤT CỦA GỐM GỒ TỪ BÃ THẢI VỎ ĐIỀU
Authors: ĐỖ TRUNG KIÊN KIỀU , VĂN KHẢI TRẦN , ĐÌNH TUẤN PHAN , QUANG MINH ĐỖ
Published: January 2021

Gốm gỗ (Woodceracmis) là sản phẩm gốm được hình thành bằng cách nung kết khối nguyên liệu có nguồn gốc từ gỗ ở nhiệt độ cao. Trong nghiên cứu này, nhóm tác giả sẽ khảo sát ảnh hưởng của hàm lượng chất kết dính nhựa thông đến tính chất của sản phẩm gốm gỗ từ nguồn nguyên liệu bã thải vỏ điều. Bã thải vỏ điều sẽ được nghiền mịn và trộn với nhựa thông ở các tỉ lệ khác nhau. Các hỗn hợp sau trộn được tạo hình bằng ép nóng ở 1300C dưới áp lực 1MPa sau đó nung ở nhiệt độ 9000C trong môi trường thiếu oxy. Các mẫu sau nung sẽ được xác các tính chất như độ bền nén (bằng phương pháp bền nén xuyên tâm), khối lượng thể tích (bằng phương pháp chiếm chỗ chất lỏng), liên kết hóa học (bằng phổ hồng ngoại FTIR), thành phần khoáng (bằng phương pháp nhiễu xạ tia X) và hình thái học (bằng kính hiển vi điện tử quét SEM). Các kết quả thu được sẽ cho những kết luận về sự biến đổi của các tính chất theo thành phần nhựa thông sử dụng.
DISTINCTION BETWEEN CRINUM LATIFOLIUM AND CRINUM ASIATICUM (AMARYLLIDACEAE) USING MOLECULAR DATA
Authors: HONG THIEN VAN , THỊ THU NGAN TRAN , THAO NGUYEN LUU , NGOC NAM TRINH
Published: January 2021

Crinum latifolium and C. asiaticum are the two species of genus Crinum, Amaryllidaceae family and they have highly medicinal values. Distinction between two species is challenging due to many similar morphological characteristics. In this study, we used molecular makers to distinguish the two species Crinum latifolium and C. asiaticum. The phylogenetic tree was constructed based on the DNA sequence data of the ITS (internal transcribed spacer) nuclear ribosomal DNA (nrDNA) sequences of Crinum latifolium and C. asiaticum. As a result, C. latifolium and C. asiaticum were sorted into two different groups in the phylogenetic tree. Therefore, C. latifolium and C. asiaticum were carried out to solve the taxonomic ambiguity.
APPLICATION OF RAYLEIGH-RITZ TECHNIQUE IN ANALYSIS OF NATURAL VIBRATION
Authors: HƯNG LÊ VĂN , PHAN ĐỖ CAO , CUNG NGUYỄN HUY , ĐẠT LÊ HỮU
Published: January 2021

The paper is the first step towards the aerodynamic analysis of slender structures to wind actions. By Rayleigh-Ritz technique and Lagrange equation, the paper describes the vibrationof a continuous structure though a system of ordinary differential equations in a way more familiar with structural analysts. This vibration method will be applied to antenna pole for dynamic analysis.
NGHIÊN CỨU CÁC NHÂN TỐ TÁC ĐỘNG ĐẾN VIỆC THU HÚT VỐN ĐẦU TƯ VÀO TỈNH QUẢNG NGÃI
Authors: TRINH NGUYỄN DUY
Published: January 2021

Nghiên cứu này nhằm mục đích tìm hiểu, nhận dạng và đo lường các yếu tố có tác động đến việc thu hút vốn đầu tư vào tỉnh Quảng Ngãi, và từ các tác động này dẫn đến việc quyết định lựa chọn Quảng Ngãi là địa điểm đầu tư lý tưởng của các nhà đầu tư trong và ngoài nước. Mẫu khảo sát bao gồm 327 quan sát. Điều tra 327 Doanh nghiệp trong nước và nước ngoài tại các khu công nghiệp đang hoạt động tại Quảng Ngãi thông qua bản câu hỏi được thiết kế sẵn. Tác giả sử dụng các phương pháp thống kê so sánh, mô tả, tổng hợp; kiểm định Cronbach’sAlpha, phân tích nhân tố khám phá EFA, phân tích nhân tố khẳng định CFA và phân tích mô hình cấu tuyến tính SEM. Kết quả khảo sát cho thấy có 7 nhân tố được đề nghị có ảnh hưởng tác động đến việc thu hút vốn đầu tư vào tỉnh Quảng Ngãi. Nghiên cứu này cũng đưa ra một số hàm ý chính sách nhằm nâng cao năng lực cạnh tranh trong việc thu hút vốn đầu tư của Quảng Ngãi.
Growth model for collaboration networks
Authors: MELEU Ghislain Romaric , MELATAGIA YONTA Paulin
Published: January 2021

We propose a model of growing networks based on cliques formations. A clique is used to illustrate for example co-authorship in co-publication networks, co-occurence of words or collaboration between actors of the same movie. Our model is iterative and at each step, a clique of λη existing vertices and (1 − λ)η new vertices is created and added in the network; η is the mean number of vertices per clique and λ is the proportion of old vertices per clique. The old vertices are selected according to preferential attachment. We show that the degree distribution of the generated networks follows the Power Law of parameter 1 + 1/ λ and thus they are ultra small-world networks with high clustering coefﬁcient and low density. Moreover, the networks generated by the proposed model match with some real co-publication networks such as CARI, EGC and HepTh.

Nous proposons un modèle de croissance de graphe basé sur la formation de clique. Une clique peut par exemple illustrer la collaboration entre auteurs dans un réseau de co-publication, les relations de co-occurrence des mots dans une phrase ou les relations entre acteurs d'un film. C'est un modèle itératif qui à chaque étape crée une clique de λη anciens sommets et (1 − λ)η nouveaux sommets et l'insère dans le graphe. η est le nombre moyen de sommets dans une clique et λ la proportion moyenne d'anciens sommets dans une clique. La distribution des degrés des réseaux générés suit la Loi de Puissance de paramètre 1 + 1/λ et par conséquent ce sont des réseaux petit-mondes qui présentent un coefficient de clustering élevé et une faible densité. En outre, les réseaux générés par le modèle proposé reproduisent la structure des réseaux de terrains à l'instar des réseaux de co-publication du CARI, de EGC et de HepTh.
Social network ordering based on communities to reduce cache misses
Authors: Messi Nguélé Thomas , Tchuente Maurice , Méhaut Jean-François
Published: January 2021

Last version asked for publication 10th may; finally accepted in 6th April 2017; Accepted after minor changes in 17th October 2016,

ABSTRACT. One of social graph's properties is the community structure, that is, subsets where nodes belonging to the same subset have a higher link density between themselves and a low link density with nodes belonging to external subsets. Futhermore, most social network mining algorithms comprise a local exploration of the underlying graph, which consists in referencing nodes in the neighborhood of a particular node. The idea of this paper is to use the community structure during the storage of large graphs that arise in social network mining. The goal is to reduce cache misses and consequently, execution time. After formalizing the problem of social network ordering as a problem of optimal linear arrangement which is known as NP-Complet, we propose NumBaCo, a heuristic based on the community structure. We present for Katz score and Pagerank, simulations that compare classic data structures Bloc and Yale to their corresponding versions that use NumBaCo. Results on a 32 cores NUMA machine using amazon, dblp and web-google datasets show that NumBaCo allows to reduce from 62% to 80% of cache misses and from 15% to 50% of execution time.

L'une des propriétés des graphes sociaux est leur structure en communautés, c'est-à-dire en sous-ensembles où les noeuds ont une forte densité de liens entre eux et une faible den-sité de liens avec l'extérieur. Par ailleurs, la plupart des algorithmes de fouille des réseaux sociaux comportent une exploration locale du graphe sous-jacent, ce qui amène à partir d'un noeud, à faire référence aux noeuds situés dans son voisinage. L'idée de cet article est d'exploiter la structure en communautés lors du stockage des grands graphes qui surviennent dans la fouille des réseaux so-ciaux. L'objectif est de réduire le nombre de défauts de cache avec pour conséquence l'amélioration du temps d'exécution. Après avoir formalisé le problème de numérotation des noeuds des réseaux sociaux comme un problème d'arrangement linéaire optimal qui est connu comme NP-Complet, nous proposons NumBaCo, une heuristique basée sur la struture en communautés. Nous présentons pour le score de Katz et Pagerank, des simulations comparant les structures de données classiques Bloc et Yale à leurs versions exploitant NumBaCo. Les résultats obtenus sur une machine NUMA de 32 coeurs à partir des jeux de données amazon, dblp et web-google montrent que NumBaCo contribue à diminuer les défauts de cache de 62% à 80% et le temps d'exécution de 15% à 50%.
Complexity of Opacity algorithm in data-centric workflow system
Authors: Diouf Mohamadou Lamine , Pinchinat Sophie
Published: January 2021

A property (of an object) is opaque to an observer when he or she cannot deduce the property from its set of observations. If each observer is attached to a given set of properties (the so-called secrets), then the system is said to be opaque if each secret is opaque to the corresponding observer. We study in this paper, the complexity of opacity algorithm in data-centric workflows systems. We show that the complexity of this algorithm is EXPTIME-complete. Using the reduction problem, whe show that we can reduce the complexity of opacity problem to wellknow problem, the intersection of nonemptyness problem of Tree automata in polynomial time.

Une propriété d'un objet est dit opaque pour un observateur si celui-ci ne peut déduire que la propriété est satisfaite sur la base de l'observation qu'il a de cet objet. Supposons qu'un certain de nombre de propriétés (appelées secrets) soient attachées à chaque intervenant d'un système, nous dirons alors que le systéme lui-même est opaque si chaque secret d'un observateur lui est opaque: il ne peut percer aucun des secrets qui lui ont été attachés. Dans ce papier, on se propose d'étudier la complexité du problème de l'opacité des artefacts d'un système à flots de tâches(système workflow). Nous présentons une formalisation optimale du prob-lème de l'opacité dans ces systèmes workflows. Nous étudions ensuite la complexité de l'algorithme de l'opacité pour ces systèmes.
UU polynomial matrix decomposition applying in 802.11ac beamforming
Authors: Mbaye Moustapha , Diallo Moussa , Gueye Bamba
Published: January 2021

This paper presents a MIMO-OFDM " Beamforming " approach in a IEEE 802.11ac context. This technique of " Beamforming " has the same performance as the conventional technique while allowing to perform the precoding and postcoding at one time and whatever the number of OFDM subcarriers.

Dans ce papier nous présentons une nouvelle approche de " Beamforming " en MIMO OFDM dans un contexte IEEE 802.11ac. La nouvelle technique de " Beamforming " présente les mêmes performances que la technique conventionnelle tout en permettant de réaliser le pré-codage et le post-codage en une seule fois et ce quelque soit le nombre de sous-porteuses OFDM.
An alternative algorithm for regularization of noisy volatility calibration in Finance
Authors: Ibtissam Medarhri , Rajae Aboulaich , Naima Debit
Published: January 2021

This contribution is an extension of the work initiated in [1], presenting a strategy for the calibration of the local volatility. Due to Morozov's discrepancy principle [6], the Tikhonov regularization problem introduced in [7] is understood as an inequality-constrained minimization problem. An Uzawa procedure is proposed to replace this latter by a sequence of unconstrained problems dealt with in the modified Thikonov regularization procedure in [1]. Numerical tests confirm the consistency of the approach and the significant speed-up of the process of local volatility determination.

Cette contribution dans ce papier est une extension des travaux initiés dans [1], qui pré-sente une stratégie pour l'estimation de la volatilité locale. En raison du principe de la différence de Morozov [6], le problème de la régularisation de Tikhonov introduite dans [7] est reformulé comme un problème de minimisation de l'inégalité des contraintes. Une procédure Uzawa est proposé de remplacer ce dernier par une séquence de problèmes non contraints traités dans la procédure de régularisation Thikonov modifié dans [1]. Des tests numériques confirment la cohérence de l'approche et l'importante accélérer le processus de détermination de la volatilité locale.
Chemotherapy models
Authors: Charif Fayssal , Helal Mohamed , Lakmeche Abdelkader
Published: January 2021

A chemotherapeutic treatment model for cell population with resistant tumor is considered. We consider the case of two drugs one with pulsed effect and the other one with continuous effect. We investigate stability of the trivial periodic solutions and the onset of nontrivial periodic solutions by the mean of Lyapunov-Schmidt bifurcation.

Nous considérons un modèle de chimiothérapie pour une population de cellules avec ré-sistance. Nous considérons le cas de deux médicaments le premier avec effet impulsif et le deuxième avec effet continu. Nous étudions la stabilité des solutions périodiques triviales et l'apparition des solutions périodiques nontriviales en utilisant la bifurcation de Lyapunov-Schmidt
UNIQUENESS FOR AN INVERSE PROBLEM FOR A DISSIPATIVE WAVE EQUATION WITH TIME DEPENDENT COEFFICIENT
Authors: Bellassoued Mourad , Ben Aicha Ibtissem
Published: January 2021

This paper deals with an hyperbolic inverse problem of determining a time-dependent coefficient a appearing in a dissipative wave equation, from boundary observations. We prove in dimension n greater than two, that a can be uniquely determined in a precise subset of the domain, from the knowledge of the Dirichlet-to-Neumann map.
Contribution to image restoration using a neural network model
Authors: Achour Karim , Zenati Nadia , Djekoune Oualid
Published: January 2021

The reduction of the blur and the noise is an important task in image processing. Indeed, these two types of degradation are some undesirable components during some high level treatments. In this paper, we propose an optimization method based on neural network model for the regularized image restoration. We used in this application a modified Hopfield neural network. We propose two algorithms using the modified Hopfield neural network with two updating modes : the algorithm with a sequential updates and the algorithm with the n-simultaneous updates. The quality of the obtained result attests the efficiency of the proposed method when applied on several images degraded with blur and noise.

La réduction du bruit et du flou est une tâche très importante en traitement d'images. En effet, ces deux types de dégradations sont des composantes indésirables lors des traitements de haut niveau. Dans cet article, nous proposons une méthode d'optimisation basée sur les réseaux de neurones pour résoudre le problème de restauration d'images floues-bruitées. Le réseau de neurones utilisé est le réseau de « Hopfield ». Nous proposons deux algorithmes utilisant deux modes de mise à jour: Un algorithme avec un mode de mise à jour séquentiel et un algorithme avec un mode de mise à jour n-simultanée. L'efficacité de la méthode mise en œuvre a été testée sur divers types d'images dégradées.
Who_Is : Identification system of human faces
Authors: Laskri Mohamed Tayeb , Chefrour Djallel
Published: January 2021

Although human face recognition is a hard topic due to many parameters involved (e.g. variability of the position, lighting, hairstyle, existence of glasses, beard, moustaches, wrinkles...), it becomes of increasing interest in numerous application fields (personal identification, video watch, man machine interfaces...). In this work, we present WHO_IS, a system for person identification based on face recognition. A geometric model of the face is definedfrom a set of characteristic points which are extracted from the face image. The identification consists in calculating the K nearest neighbors of the individual test by using the City-Block distance. The system is tested on a sample of 100 people with a success rate of 86 %.

Bien que la reconnaissance des visages humains soit un domaine difficile à cause de la multitude des paramètres qu'il faut prendre en compte (variation de posture, éclairage, style de coiffure, port de lunettes, de barbes, de moustaches, vieillesse…), il est très important de s'en intéresser vu les nombreux champs d'applications (vérification de personnes, télésurveillance, interfaces homme-machine …). Dans ce travail nous présentons la mise en œuvre de WHO_IS, un système d'identification de personnes par reconnaissance des visages humains. Nous avons développé un modèle géométrique du visage basé sur un ensemble de points caractéristiques extraits à partir de l'image du visage. La procédure d'identification consiste à calculer les K plus proches voisins de l'individu test dans le sens de la distance City-Block. Le système WHO_IS a été testé sur un échantillon de 100 personnes. Un taux de reconnaissance correcte de 86% a été obtenu
An algorithm for computing the reversal degree of planar topological graphs
Authors: Nzali Jean-Pierre , Porgy Koumpo Tanékou , Tapamo Hippolyte
Published: January 2021

One characteristic of planar topological graphs is the reversal degree. In this paper, we propose an improve algorithm for calculating the reversal degree of a planar topological graphs. This algorithm explores various possible cases following the descending method. Practical tests carried out on machine, using graphs with more than fifty internal vertices of odd degree, have been realized within reasonable computing time.

Le degré de retournement est une caractéristique des graphes planaires topologiques. Dans cet article nous proposons un algorithme amélioré pour calculer le degré de retournement d'un graphe planaire topologique. Cet algorithme explore les différents cas possibles suivant une méthode descendante. Son implémentation sur machine a donné lieu à des tests sur des cas pratiques, ceci en des temps de calcul tout à fait raisonnables, sur des graphes dont l'un comporte plus d'une cinquantaine de sommets intérieurs de degré impair
Interactive layout and handling of mathematical formulas in structured documents
Authors: Naciri Hanane , Rideau Laurence
Published: January 2021

Tools dedicated to mathematics need to display formulas and to interact with them. In this paper, we present a summary of existing tools, then we describe FIGUE, an incremental two dimensional layout engine, developed at INRIA, to get a specialized toolbox for building customized editors and graphical user interfaces. Finally we give an exemple of interface using FIGUE to develop mathematical proofs on computer.

Afficher des formules mathématiques et interagir avec ces formules sont des atouts primordiaux pour les outils informatiques dédiés aux mathématiques. Dans cet article, nous faisons un bilan des outils existants puis nous décrivons FIGUE, moteur d'affichage interactif incrémental et bidimensionnel, développé à l'INRIA, pour obtenir une bibliothèque dédiée au développement d'éditeurs de documents structurés et d'interfaces graphiques. Enfin nous montrons un exemple d'utilisation de FIGUE, dans le cadre du développement de preuves mathématiques sur ordinateur.
Parameters identification: an application to the Richards equation
Authors: Ngnepieba Pierre , Le Dimet François Xavier , Boukong Alexis , Nguetseng Gabriel
Published: January 2021

Inverse modeling has become a standard technique for estimating hydrogeologic parameters. These parameters are usually inferred by minimizing the sum of the squared differences between the observed system state and the one calculed by a mathematical model. Since some hydrodynamics parameters in Richards model cannot be measured, they have to be tuned with respect to the observation and the output of the model. Optimal parameters are found by minimizing cost function and the unconstrained minimization algorithm of the quasi-Newton limited memory type is used. The inverse model allows computation of optimal scale parameters and model sensi-tivity.

La modélisation inverse est devenue une approche fréquemment utilisée pour l'estimation des paramètres en hydrogéologie. Fondamentalement cette technique est basée sur les méthodes de contrôle optimal qui nécessitent des observations et un modèle pour le calcul des dérivées du premier ordre. Le modèle adjoint du modèle de Richards est construit pour obtenir le gradient de la fonction coût par rapport aux paramètres de contrôle. Les paramètres hydrodynamiques sont pris comme paramètres de contrôle; leurs valeurs optimales sont trouvées en minimisant la fonction coût ceci en utilisant un algorithme de minimisation de type descente quasi-Newton. Cette approche est utilisée pour l'identification des paramètres hydrodynamiques sur un modèle d'écou-lement souterrain en zone non saturée, ainsi que les études de sensibilité du modèle.
An Algorithm for the Construction of a Formal Concept Lattice and for the Extraction of Minimal Generators
Authors: Ben Tekaya Sondess , Ben Yahia Sadok , Slimani Yahia
Published: January 2021

The extremely large number of association rules that can be drawn from ―even reasonably sized datasets―, bootstrapped the development of more acute techniques or methods to reduce the size of the reported rule sets. In this context, the battery of results provided by the Formal Concept Analysis (FCA) allowed to define "irreducible" nuclei of association rule subset better known as generic basis. However, a thorough overview of the literature shows that all the algorithms dedicated neglected an essential component: the relation of order, or the extraction of the minimal generators. In this paper, we introduce the GenAll algorithm to build a formal concept lattice, in which each formal concept is "decorated" by its minimal generators. The GenAll algorithm aims to extract generic bases of association rules. The main novelty in this algorithm is the use of refinement process to compute immediate successor lists to simultaneously determine the set of formal concepts, their underlying partial order and the set of minimal generators associated with each formal concept. Carried out experiments showed that the GenAll algorithm is especially efficient for dense extraction contexts compared to that of Nourine et al. Response times obtained from the GenAll algorithm largely outperform those of Nourine et al.

Le nombre prohibitif de règles d'association qui peuvent être dérivées même pour des bases de données de taille raisonnable est à l'origine du développement de techniques pour réduire la taille de l'ensemble de ces règles. Dans ce contexte, les résultats obtenus par l'Analyse de Concepts Formels (AFC) a permis de définir un sous-ensemble de règles appelé base générique. Cependant, un survol de la littérature montre que tous les algorithmes qui leur sont dédiés ont négligé une composante essentielle : soit la relation d'ordre sous-jacente ou c'est l'extraction des générateurs minimaux qui manque à l'appel. Dans ce papier, nous proposons un algorithme, appelé GenAll, pour construire un treillis de concepts formels, dans lequel chaque concept formel est "décoré" par ses générateurs minimaux. L'objectif de cet algorithme est d'extraire toute la connaissance nécessaire pour extraire les bases génériques des règles d'association. La principale originalité de GenAll est l'emploi d'un processus de raffinement des listes des successeurs immédiats pour déterminer, d'une manière simultanée, l'ensemble des concepts formels, leur ordre partiel sous-jacent et l'ensemble de générateurs minimaux associés à chacun des concepts formels. Les résultats expérimentaux ont prouvé que l'algorithme proposé est particulièrement efficace pour des contextes d'extraction denses comparé à Nourine et al. Le temps de réponse de l'algorithme GenAll surpasse celui de l'algorithme de Nourine et al.
Time-lag Derivative Convergence for Fixed Point Iterations
Authors: Griewank Andreas , Kressner Daniel
Published: January 2021

In an earlier study it was proven and experimentally confirmed on a 2D Euler code that fixed point iterations can be differentiated to yield first and second order derivatives of implicit functions that are defined by state equations. It was also asserted that the resulting approximations for reduced gradients and Hessians converge with the same R-factor as the underlying fixed point iteration. A closer look reveals now that nevertheless these derivative values lag behind the functions in that the ratios of the corresponding errors grow proportional to the iteration counter or its square towards infinity. This rather subtle effect is caused mathematically by the occurrence of nontrivial Jordan blocks associated with degenerated eigenvalues. We elaborate the theory and report its confirmation through numerical experiments

Une étude antérieure a prouvé et vérifié expérimentalement sur un code Euler 2D que les calculs itératifs avec point fixe peuvent être différenciés pour obtenir les dérivées aux premier et deuxième ordres des fonctions implicites définies par des équations d'état. On considérait également que des itérées correspondantes des gradients et Hessiens réduits convergent à la même vitesse que l'itération de point fixe d'origine. Cette étude plus détaillée révèle néanmoins que ces dérivées convergent avec un certain retard par rapport aux valeurs de la fonction. En effet le rapport des erreurs correspondantes croît vers l'infini proportionnellement au compteur d'itérations ou à son carré. Mathématiquement, cet effet plutôt subtil est causé par l'apparition de blocs de Jordan correspondant à des valeurs propres dégénérées. Nous construisons un modèle théorique de cet effet et nous le validons par des expériences numériques.