bluuebunny/crossref_metadata_2025 huggingface dataset:
Clinical retrospective analysis of 70 discharged patients with the Coronavirus disease 2019 (COVID-19) in Hangzhou, Zhejiang Province
Authors: Zuo Zhongbao , Wu Jing , Wang Miaochan , Jin Yujiao , Yu Wenyan , Niu Haiying , Chen Yangjun , Liu Pengbo , Zeng Deyu , Sui Dongming , Cai Zhaobin , Xu Aifang
Published: May 2020

Background Since the Coronavirus Disease 2019 (COVID-19) was first identified in Wuhan, China, caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) pathogen, the disease has been found in many countries. Considering the lack of effective drugs and rapid spread of COVID-19, we did a clinical detailed retrospective analysis of 70 discharged patients which can help us to better determine the clinical features of the disease.Method We collected demographic, epidemiological, clinical, laboratory, and chest computed tomographic (CT) data from patients’ hospital records, the time period were from hospitalization day1 to day7 and hospitalization last day. The retrospective study totally included 70 COVID-19 patients.Results The median age was 43 (IQR: 34-56) years. 41 (58.6%) patients were female, and there were 33 (47.1%) patients who were hospitalized more than 14 days. 18 (25.7%) patients were residents of Wuhan or recently travelled to Wuhan, 38 (54.3%) patients were having a close contact with the COVID-19 patients. The most common pre-existing diseases were liver disease (15.7%), hypertension (12.9%), renal disease (8.6), lung disease (5.7%). The time from illness onset to hospitalization was 4 (IQR: 2-7) days. The most common treatment regimen was Lopinavir/ritonavir (LPV) + Interferon alpha inhalation (IAI) + Arbidol. Compared with hospitalization day1, White blood cell count, C-reacting protein, Potassium, Aspartate aminotransferase, Lactate dehydrogenase, and Lactic acid were significantly different than hospitalization day-last. The median number of times a patients receiving chest computed tomography (CT) from day1 to day7 was 3 (IQR: 3-4). The typical chest computed tomographic images were patchy shadows and ground glass opacity.Conclusion Currently, there are no specific antiviral therapies for COVID-19. 70 COVID-19 patients in our study responded positively to treatment during the two-week period. For those discharged patients with abnormal results, more attention is needed in the future studies to control the transmission.
Hepatitis B virus Reactivation in Patients Receiving Tocilizumab for Rheumatoid Arthritis: A Long‐term, Retrospective Observational Study
Authors: Hsuan Kuo Meng , Tseng Chih-Wei , Lu Ming-Chi , Tung Chien-Hsueh , Tseng Kuo-Chih , Huang Kuang-Yung , Lee Chi-Hui , Lai Ning-Sheng
Published: May 2020

Aim To investigate the risk of hepatitis B virus (HBV) reactivation in patients undergoing long-term tocilizumab (TCZ) therapy for rheumatoid arthritis (RA). Method From January 2011 through August 2019, a total of 134 RA patients who received TCZ at Dalin Tzu Chi Hospital were screened. Patients were excluded if they were < 20 years, without complete data, or received TCZ for less than 3 months. A total of 97 patients were enrolled in this retrospective study. Clinical data, co-medications, and the occurrence of HBV reactivation were recorded. Results Of the 97 enrolled patients, 7 were HBsAg+ (7.2%), 64 were HBsAg−/HBcAb+ (61%) and 26 were HBsAg−/HBcAb+ (26.8%). The median disease follow-up time was 9 years (range, 1–18 years). TCZ was administered for a median of 29 months (range, 3–91 months). Four patients (4.1%) experienced HBV reactivation after TCZ therapy. Of the 7 HBsAg+ patients, 4 received antiviral prophylaxis and had no HBV reactivation; the remaining 3 patients had no antiviral prophylaxis, and all 3 (100%) experienced early HBV reactivation and hepatitis flare (median time to event, 6 months; range, 5–8 months). Hyper-bilirubinemia occurred in 2 of these 3 patients, with mild prothrombin time prolongation in one. After salvage entecavir treatment, all patients had a favorable outcome. Of the 64 HBsAg−/HBcAb+ patients, only one became positive for serum HBV DNA (2.5 × 10 7 IU/mL) after 18 months of TCZ treatment (1.6%; 1/64). This patient was immediately treated with entecavir, which prevented hepatitis flare. Conclusions HBsAg+ RA patients undergoing TCZ treatment are at high risk of HBV reactivation, which is prevented by antiviral prophylaxis. HBsAg−/HBcAb+ patients also are at risk of HBV reactivation. Although their risk of reactivation is lower than that of HBsAg+ patients, strict monitoring of their HBV status is still necessary.
The most important evaluation index for postgraduate medical students’ scientific research capacity: A cross-sectional survey in Shanghai, China
Authors: Wang Yan , Zhang Feifei
Published: May 2020

BackgroundPostgraduate medical students’scientific research capability is an essential part for educational system, the current research on students’ research behavior mainly focused on the students’research attitude ,innovative ability and training methods and approaches. Therefore, we carried out this study to explore the evaluation index of postgraduate medical students’scientific research capacity,in order to establish a framework of postgraduate medical students’scientific evaluation.MethodsWe designed a 39-items questionnaire to explore the evaluation index of research capacity on the perspective of postgraduate students .The questionnaire consisted of items including demographics and other 34 items about index reflect one’s scientific research ability.The participants choose the number(1-5) according the importance of each items they think.1 means not important at all;2 means not important;3 means neutral;4 means important;5 means very important.ResultsThe most important indices are ”Follow three basic ethical principles: respect, benefit and justice”(4.46±0.845);”Resist behaviour such as"data fraud, submission fraud" and other academic misconduct(4.44±0.922)”;”Adhere to the principle of patient-oriented, fully informed and voluntary participation”(4.36±0.871);”The questionnaire can be divided into four parties”Research skills and output(36.046%)”,“Theoretical and practical basis(16.034%)”,”Study Attitude(14.411)”,”Ethical of research(8.371%)”.ConclusionWe should strengthen the training of scientific research ethics knowledge, ethical consciousness and scientific research ethics of postgraduate medical students;Improve the consciousness of patent granted;Enhance the research interest of clinical-oriented students and verify the scientific of the questionnaire further.
Association of uric acid and glucose disposal rate value in euglycemic Chinese subjects
Authors: Yuan Tao , Liu Shixuan , Dong Yingyue , Fu Yong , Tang Yan , Zhao Wei-Gang
Published: May 2020

Background: We aimed to examine the relationship between serum uric acid (SUA) levels and glucose disposal rate value (M value) evaluated by hyperinsulinemic euglycemic clamp technique in euglycemic Chinese subjects.Methods: There were 19 non-diabetic Chinese subjects included in this study. The participants accepted physical examination, laboratory examination and standardized questionnaire. Insulin resistance was evaluated by M value. Some other indices were also calculated by data obtained from 3-hour oral glucose tolerance test (OGTT). Subjects were divided into two groups based on the median of SUA levels.Results: The level of systolic blood pressure (SBP) (P=0.035), waist circumference (P=0.009), waist-to-hip ratio (P=0.004), Chinese visceral adiposity index (CAVI) (P=0.028), weight (P=0.01), serum creatinine (Cr) (P=0.05) and the percentage of drinking habits (P=0.03) were all significantly increased in high SUA group. The level of M value and high-density lipoprotein cholesterol (HDL-c) were significantly decreased in high SUA group (P=0.041 for M value and P=0.09 for HDL-c). There were no significant differences between those indirect insulin resistance indices and SUA. In addition, the SUA levels were inversely correlated with M value (r=-0.666, P=0.002) and HDL-c (r=-0.619, P=0.005), positively correlated with waist circumference (r=0.615, P=0.005), CVAI (r=0.630, P=0.004), SBP (r=0.521, P=0.022) and Cr (r-0.550, P=0.015) levels. Analysis of stepwise multiple regression showed the independent association between SUA and M value in both male and female euglycemic subjects.Conclusions: There is a significant correlation between SUA levels and glucose disposal rate value in euglycemic Chinese subjects, which suggested that UA played an important role on insulin resistance even in those non-diabetic subjects
Hsa-MiR-590-3p promotes the malignancy progression of pancreatic ductal carcinoma cell by inhibiting the expression of p27 and PPP2R2A via G1/S cell cycle pathway
Authors: Shi Xiaoyang , Sheng Weiwei , Jia Chao , Tang Jingtong , Dong Ming
Published: May 2020

Background: miR-590-3p plays an important role in the occurrence and development of many cancers, but its role in pancreatic cancer has not been reported. Objective: Investigate the effect and target genes of miR-590-3p in pancreatic cancer, so as to provide new diagnostic and therapeutic ideas for pancreatic cancer. Methods: qRT-PCR, MTT, clonal formation assay, flow cytometry and transwell assay were used to detect malignant cell behaviors. TargetScan (http://www.targetscan.org) was used to predict the binding region of miR-590-3p to target genes. Immunohistochemistry and Western blot were used to detect protein expression.Results: hsa-miR-590-3p expressed significantly higher in PC tissues than paired normal pancreas and its expression level was associated with PC tumor size (P=0.042) and preoperative CA19-9 level (P=0.046). Its overexpression promoted PC cell proliferation, invasion and migration following with the p27 and PPP2R2A protein down-regulation, and vice versa. Dual-luciferase reporter assay confirmed that p27 and PPP2R2A were direct target genes of miR-590-3p. Overexpression of P27 and PPP2R2A reversed the promoting effect of miR-590-3p on cell proliferation, migration and invasion. Conclusion: MiR-590-3p promote the development of pancreatic cancer by directly downregulated p27 and PPP2R2A via the G1/S cell cycle pathway.
Validation of self-reported physical activity by accelerometry in Tanzanian primary school children
Authors: Mosha Mary Vincent , Kasagama Elizabeth , Ayieko Philip , Todd Jim , Msuya Sia , Grosskurth Heiner , Filteau Suzanne
Published: May 2020

Background: Insufficient physical activity is a serious public health concern. Assessing physical activity accurately in children remains a challenge and valid tools for its assessment in African children are needed. This study compares self-reports versus accelerometry-captured physical activity.Methods: In this cross-sectional study, 51 primary school children aged 9 – 11 years from four primary schools in Kilimanjaro region were enrolled. Children were asked to complete a self-reported questionnaire on physical activity and wore an accelerometer for seven consecutive days. Accelerometry was used as a reference method to assess for child reporting accuracy.Results: Spearman correlation between self-reports and accelerometry was moderate (r=0.41, p=0.002). Children who reported walking to school had higher moderate to vigorous physical activity (MVPA) for both accelerometry and self- reports compared to their counterparts (p < 0.001). Intra-class correlation (ICC) showed that 32% of the variations in accelerometry weekly total MVPA was contributed by the differences in activities between children.Conclusions: Objective measures of physical activity such as accelerometers can be used to accurately measure physical activity in children where feasible. Self-reports have limited validity, and therefore more research is needed to develop better self-reported measures with specific activities which can easily be recalled by children.
Prevalence and related factors of internet addiction among undergraduate university students in Ethiopia. A community university-based cross-sectional study
Authors: Zenebe Yosef , Kunno Kunuya , Mekonnen Meseret , Bewuket Ajebush , Birkie Mengesha , Necho Mogesie , Seid Muhammed , Tsegaw Million , Akele Baye
Published: May 2020

Background

Globally, more than three billion people use the internet daily with young people being the most common users. Internet addiction among university students in Ethiopia has not been studied.

Objectives

The main objective of this study was to assess the prevalence and related factors of internet addiction among Wollo university students in Ethiopia.

Methods

A community university-based cross-sectional study was conducted among Wollo University students from April 10 to May 10, 2019. A total of six hundred three students were participated in the study using a pilot tested and self-administered structured questionnaire. A multistage cluster sampling was adopted for this study. In the first stage, by the use of lottery method, two colleges (College of medicine and health sciences, and College of natural sciences, and one school (school of law)) were selected. In the second stage, 18 departments were selected from the colleges and school. The Young’s Internet Addiction Test instrument was used to assess the level of internet addiction.

Results

Generally, the prevalence of internet addiction (IA) among the current internet users was 85% (n=466) with 55.7%(n=305) mild internet addiction, 27.9% (n=153) moderate internet addiction and 1.5% (n= 8) severe internet addiction. In multivariable logistic regression analysis, spending more time on the internet (adjusted odds ratio (AOR) = 10.13, 95%CI: 1.33-77.00)), having mental distress (AOR = 2.69, 95%CI: 1.02-7.06), playing online games (AOR = 2.40, 95%CI: 1.38-4.18), current khat chewing (AOR = 3.34, 95%CI: 1.14-9.83) and current alcohol use (AOR = 2.32, 95%CI: 1.09-4.92) were positively related to internet addiction. Using the internet for more than twelve months (AOR = 0.42, 95%CI: 0.18-0.96) and using the internet by mobile internet (AOR = 0.40, 95%CI: 0.20-0.83) were negatively related to internet addiction.

Conclusions

The current study documents a high prevalence of internet addiction among Wollo University students. Factors independently associated with internet addiction were using the internet greater than five hours daily, having mental distress, playing online games, current khat chewing and current alcohol use. So, we advise that higher institutions should establish prevention programs focus on educating students about emotional regulation skills and the harmful effects of substance use to minimize internet addiction.
Mapping of PubMed Literature on Early Trends of 2019 Novel Coronavirus (COVID-19)
Authors: Kumar Kutty
Published: May 2020

2019 novel corona virus infection (COVID-19) causes extreme viral pneumonia in people, known to have a high death rate and a similitude in clinical indications with Severe Acute Respiratory Syndrome coronavirus. This investigation intended to study the attributes of distributions on early COVID-19 research through bibliometric analysis. PubMed database was looked on 07, February, 2020 for COVID-19 distributions published during 01st December 2019 to 06th February 2020. Investigation parameters incorporate year of production, distribution type, examples of universal coordinated effort, and research organizations. An aggregate of 62 COVID-19 research distributions were distributed during the examination time frame. The exploration works were distributed from 13 nations, demonstrating the global noteworthiness on coronavirus episode. USA was the biggest supporter, with 24 articles distributed over a range of 2months and 6 days, trailed by England (11 articles). Aftereffects of the investigation will bear some significance with understudies, specialists, curators and data science experts, and will fill in as a pattern for resulting examinations.
Early effect of SARS-COV-2 on renal tubule: a pilot study
Authors: Wang Mengyan , Dong Xiaotian , Yan Jun , Zhang Zhongdong , Shi Jinchuan , Liu Shourong
Published: May 2020

Objective: To explore the early clinical characteristics of coronavirus disease 2019 (COVID-19) and provide a reference for the early prevention and treatment of the disease.Methods: We collected and analyzed demographic data, medical history, exposure history, underline diseases, symptoms, signs, laboratory data, chest computed tomographic (CT) scans, and treatment measures of COVID-19 patients admitted to the Sixth People's Hospital of Hangzhou from January 20 to February 23, 2020.Results: Among 51 confirmed COVID-19 patients included in this study, 7.8% (4/51) patients were severe and 45.1% (23/51) were male. Median age was 43 years (IQR, 23). Fever (54.9%, 28/51) and cough (52.9%, 27/51) were the main symptoms. 74.5% (38/51) patients had a history of exposure and 17.6% (9/51) patients had a history of hypertension. Importantly, most (60.8%, 31/51) patients had an increase of urine β2 microglobulin. In addition, the inflammation indexes (C-reactive protein and serum amyloid A) of patients with elevated urine β2 microglobulin were significantly increased (p = 0.017 and p = 0.049) and lymphocytes count was significantly reduced (p = 0.012), compared with patients with normal urine β2 microglobulin. Correlation analysis showed that urine β2 microglobulin was positively correlated with C-reactive protein and serum amyloid A; but negatively correlated with lymphocytes count.Conclusions: COVID-19 patients have obvious symptoms of lung injury, but the occurrence of early renal tubular injuries has to be monitored vigilantly.
The Role of Social Influence and Network Churn in Beliefs about Electronic Medical Record Technology
Authors: Yuan Christina T. , Kane Gerald C. , Fletcher Jason M. , Nembhard Ingrid M.
Published: May 2020

The successful implementation of technology often hinges on individual beliefs about the innovation being introduced. Little is known about how social networks shape these beliefs. In this study, we examine: (1) whether individual beliefs about technology are influenced by the beliefs of their peers within their social networks (network content); and (2) whether changes in the composition of the social network over time (network churn) moderates the effect of peer beliefs on individual beliefs. We offer and test hypotheses about these relationships using longitudinal social network survey data from hospital staff collected 2 – 4 months before (N = 256) and 3 – 5 months after (N = 284) the implementation of a new electronic medical record (EMR) system at a large, academic hospital. Our findings suggest that peer beliefs about new technology significantly and negatively affect individual beliefs about technology in the early stages of EMR implementation. We also find that the effect of peer beliefs on individual beliefs is stronger in more stable social networks (i.e., social networks that experience few tie deletions over time) and weaker in less stable social networks (i.e., social networks that experience many tie deletions over time). Our study examines social influence in a novel context – the implementation of EMR systems in the hospital setting – and extends network theory by conceptualizing network churn as a moderating variable that may amplify or dampen the effect of networks.
Adolescent Friendship Formation and Mental Health: A Stochastic Actor-Based Model of Help-Seeking Behavior
Authors: Mundt Marlon P. , Zakletskaia Larissa I.
Published: May 2020

This study investigates how adolescent peer friendship formation relates to help-seeking behavior and how the structure of peer social networks contributes to the creation of social connections by psychological counseling recipients. The study sample comprised 2,264 adolescents ages 12-19 from the National Longitudinal Study of Adolescent Health (Add Health). Stochastic actor-based modeling simulated the co-dependence of peer friendship networks and adolescent help-seeking behavior from an initial data state to a final data state while accounting for social selection and influence effects in the same model. Results indicated that adolescents who sought psychological counseling in the past year nominated 65% more peers as friends than otherwise identical adolescents who did not use psychological services. Adolescent psychological counseling did not contribute to the loss of friends. Users of psychological services were twice as likely to be named as friends in highly interconnected peer social networks (i.e. more friendship connections among their friends), as opposed to individuals in less interconnected peer groups. The findings indicate improved social functioning of adolescents as a result of psychological counseling. The results advocate for use of psychological services and point to the necessity of wide-spread screening and early detection and treatment of mental ill-health among U.S. adolescents. Group interventions targeting building social skills to enhance peer group social network interconnectivity may promote better social connections for adolescent users of psychological counseling.
Structural and Contextual Patterns in Family Health History Knowledge among African American Adults: A Mixed-Methods Social Network Analysis Study*
Authors: Hood Sula M. , Golembiewski Elizabeth H. , Sow Hadyatoullaye , Benbow Kyle , Prather Jeremy , Robison Lisa D. , Martin-Hagler Elisabeth
Published: May 2020

Background: Family health history is a strong risk factor for many chronic diseases. Ethnic minorities have been found to have a low awareness of their family health history (FHH), which may pose a contributing factor to health disparities. Purpose: The purpose of this mixed-methods social network analysis study was to identify structural and contextual patterns in African American adults’ FHH knowledge based on interpersonal communication exchanges with their family members. Methods: African American adults completed individually administered family network interviews. Participants’ 3-generation family pedigree served as a visual aid to guide their interview. Our primary outcome of interest for this analysis was whether a family member was reported as someone who talks to the participant about their own (i.e., the family member’s) health, which we refer to as a “personal health informant.” To contextualize quantitative findings, participants were asked to describe how they learned about the health history of the relatives they identified during their interview. Results: Participants (n=37) reported an average family network size of 29.4 relatives (SD = 15.5; Range = 10-67). Each participant, on average, named 17% of their familial network as personal health informants. Multivariate regression results showed that participants were more likely to name an alter as a personal health informant if the alter was female (OR = 2.14, p = 0.0519), from the maternal side of the participant’s family (OR = 1.12, p = 0.0006), had one or more chronic health conditions (OR = 2.41, p = 0.0041), was someone who has discussions with the participant about the participant’s health (OR = 16.28, p < 0.0001), was a source of family health information (OR = 3.46, p = 0.0072), and was someone whose health the participant helps to monitor or track (OR = 5.93, p = 0.0002). Complementary qualitative findings indicate that FHH knowledge is facilitated by open, direct communication among relatives. Personal health informants were described as disclosing information for the purposes of informing others for preventive purposes and for gaining social support. Participants also learned about FHH via other methods, including direct observation, during caretaking, and following a relative’s death. Conclusions: Communication and disclosure practices is an important determinant of African Americans’ FHH knowledge. More culturally and contextually meaningful public health efforts are needed to promote family health history sharing, especially regarding paternal family health history, siblings, and extended relatives.
Transitivity Types Predict Communicative Abilities in Infants at Risk of Autism*
Authors: Schleier Rebekka , Iverson Jana M. , King Andrew P. , West Meredith J.
Published: May 2020

To examine predictors of preschool language abilities, thirty-seven infants at high risk for Autism Spectrum Disorder (ASD) were recorded longitudinally from 5-14 months as they interacted with their caregivers and toys at home. Triadic interactions were coded, categorized as transitive, intransitive or vacuously transitive, and then related to the MacArthur Bates Communicative Development Inventory (CDI-III) and the Mullen Scales of Early Learning (MSEL) at 36 months. The results show that prior to 14 months, early transitive interactions correlate positively and intransitive interactions correlate negatively with CDI-III and MSEL scores at 36 months. By categorizing interactions between 5-14 months by transitivity, we have demonstrated that recurring triadic patterns can predict communicative abilities at 36 months.
Sender- and receiver-specific blockmodels
Authors: Geng Zhi , Nowicki Krzysztof
Published: May 2020

We propose a sender-specific blockmodel for network data which utilizes both the group membership and the identities of the vertices. This is accomplished by introducing the edge probabilities (ŵ¿,ν) for 1 ≤ i ≤ c, 1 ≤ v ≤ n, where í specifies the group membership of a sending vertex and ν specifies the identity of the receiving vertex. In addition, group membership is consider to be random, with parameters (í>í)í=io We present methods based on the EM algorithm for the parameter estimations and discuss the recovery of latent group memberships. A companion model, the receiver-specific blockmodel, is also introduced in which the edge probabilities (≠uj) for 1 ≤ u ≤ n, 1 < j < c depend on the membership of a vertex receiving a directed edge. We apply both models to several sets of social network data.
Using Visualizations to Explore Network Dynamics
Authors: Chu Kar-Hai , Wipfli Heather , Valente Thomas W.
Published: May 2020

Network analysis has become a popular tool to examine data from online social networks to politics to ecological systems. As more computing power has become available, new technology-driven methods and tools are being developed that can support larger and richer network data, including dynamic network analysis. This timely merger of abundant data and cutting edge techniques affords researchers the ability to better understand networks over time, accurately show how they evolve, find patterns of growth, or study models such as the diffusion of innovation. We combine traditional methods in social network analysis with new innovative visualizations and methods in dynamic network studies to explore an online tobacco-control community called GLOBALink, using almost twenty years of longitudinal data. We describe the methods used for the study, and perform an exploratory network study that links empirical results to real-world events.
Network Text Analysis in Computer-Intensive Rapid Ethnography Retrieval: An Example from Political Networks of Sudan*
Authors: Tambayong Laurent , Carley Kathleen M.
Published: May 2020

Advances in text analysis, particularly the ability to extract network based information from texts, is enabling researches to conduct detailed socio-cultural ethnographies rapidly by retrieving characteristic descriptions from texts and fusing the results from varied sources. We describe this process and illustrate it in the context of conflict in the Sudan. We show how network information can be extracted from vast quantities of unstructured texts-based information using computer assisted processes. This is illustrated by an examination of changes in the political networks in Sudan as extracted from the Sudan Tribune. We find that this approach enables rapid high level assessment of a socio-cultural environment, generates results that are viewed as accurate by subject matter experts, and match actual historical events. The relative value of this socio-cultural analysis approach is discussed.
Evaluation of Physiological and Biochemical Responses against to Salinity in Local Rice (Oryza sativa L.) under in vitro Conditions
Authors: ORCAN Mehmet Yusuf , AKBAŞ Filiz
Published: May 2020

In a local rice cultivar (Karacadağ), physiological and biochemical changes caused by different salt types (NaCI, CaCI2, MgCI2) and their concentrations (25, 50, 75, 150, 300 mM) were investigated under stress conditions. The germination percentage was not affected at low concentrations in each of 3 types salt tested but it decreased significantly as the concentration increased. In development stages of seedling, it was determined that as the concentration increased in all salt types, plant growth and relative water content (RWC) decreased. Salinity was mostly affected the photosynthetic pigment contents of the plants and there was a difference significantly between the results according to the salt concentration. In general, it was determined that malondialdehyde (MDA) content increased depending on the concentration in all salt types that tested. The highest cell membrane damage was found in the 75 mM application of CaCI2 with 4.1820 μmol /g MDA. As a result, it was determined that germination and seedling development stages were negatively affected in the salt types tested, especially at high concentrations.
Bazı Antibiyotiklerin Biyofilm Oluşturan Stafilokok İzolatları Üzerindeki Etkilerinin Değerlendirilmesi
Authors: ERDOĞMUŞ Sevim Feyza , KONAK Selahattin
Published: May 2020

Stafilokoklar çeşitli virülans faktörlere sahip olan patojen mikroorganizmalardır. Bu virülans faktörlerden birisi biyofilm üretimidir. Bazı stafilokoklar, biyofilm üreterek antibiyotiklere karşı dirençli hale gelmektedir ve enfeksiyonların tedavisi zorlaşmaktadır. Bu çalışmanın amacı, daha önce bir çalışmada mastitisli inek sütlerinden izole edilmiş olan stafilokok izolatlarının planktonik ve biyofilm oluşturan formlarının üzerine vankomisin, eritromisin, oksasilin antibiyotiklerinin etkisini belirlemektir. Antibiyotiklerin minimum inhibitör konsantrasyonu (MİK), biyofilm minimum inhibitör konsantrasyonu (MBİK) ve minimum biyofilm eradikasyon konsantrasyonu (MBEK) değerleri belirlenmiştir. Antibiyotiklerin MİK, MBİK ve MBEK değerleri karşılaştırıldığında; en yüksek MİK değeri (32-64 μg ml-1) eritromisin için olduğu belirlenmiştir. MBİK ve MBEK değerleri ise tüm antibiyotikler için benzerlik göstermiştir. Bu çalışmanın sonucunda, stafilokok izolatlarının biyofilm oluşturarak antibiyotiklere karşı daha dirençli hale geldikleri ve serbest yaşayan formlarına göre daha yüksek dozda antibiyotiklerden etkilendikleri saptanmıştır.
Ticari ve Lokal Kefir Danelerinden Elde Edilen Kefirlerin Biyoaktivitelerinin Karşılaştırılması
Authors: YİRMİBEŞOĞLU Side Selin Su , TEFON ÖZTÜRK Burcu Emine
Published: May 2020

Fermente süt ürünlerinden kefir özellikle son yıllarda sağlık üzerindeki etkileri nedeniyle sıklıkla tercih edilmektedir. Geleneksel yöntemle hazırlanan kefirde kullanılan danelerin mikrobiyolojik içerikleri, elde edildikleri bölge ile oldukça ilişkilidir ve üretilen kefirin özelliklerini doğrudan etkilemektedir. Dolayısıyla kullanılan danelerin biyoaktivitelerinin incelenmesi önem teşkil etmektedir. Bu çalışmada Antalya, Türkiye bölgesinden lokal bir dane ve ticari dane ile fermente edilen keçi ve inek sütleri kefirlerinin biyoaktivitelerinin karşılaştırmalı analizi yapılmıştır. Bu amaçla, kefir örneklerinin mikrobiyolojik analizleri, antibakteriyel, antioksidan aktivite analizleri, toplam fenolik madde ve toplam flavonoid miktar tayinleri yapılmıştır. Elde ettiğimiz sonuçlar lokal dane ile elde edilen kefirlerin antioksidan ve antibakteriyel aktivitelerinin ticari dane ile üretilenlere oldukça yakın olduğu ve aynı zamanda fenolik madde ve flavonoid açısından tüketicilerin güvenle kullanabilecekleri bir alternatif olduğunu göstermektedir.
Kenevir Zararlıları ile Entegre Mücadele
Authors: KÜÇÜKTOPÇU Yeter , SARUHAN İslam , YİĞİT Şeyma , AKÇA İzzet
Published: May 2020

Kenevir ekim alanları farklı nedenlerden dolayı son yıllarda artmaktadır. Bu nedenle kenevirde zarar yapma potansiyeli olan türlerin önemi her geçen gün artacaktır. Ülkemizde kenevirlerde zarar yapan zararlılara yönelik kayıtlar yok denecek kadar azdır. Ancak günümüzde bazı zararlılardan şikayet edilmektedir. Dünyanın değişik bölgelerinde kenevirlerde önemli kayıplara neden olan ve ülkemizde de varlığı bilinen bu zararlı türlerin, kenevir üretiminde potansiyel zararlı olma ihtimali vardır. Bu türler arasında; Avrupa mısır kurdu [Ostrinia nubilalis (Hübner) (Lepidoptera: Crambidae)], Avrasya kenevir kurdu [Grapholita delineana (Walker) (Lepidoptera: Tortricidae)], Kenevir pire böcekleri [Psylliodes attenuata Koch, P. punctulata Melsh, Phyllotreta pusilla Horn, P. nemorum Linnaeus ve Systena blanda Melsheime (Coleoptera: Chrysomelidae)], Kenevirde zararlı yaprak bitleri [Mysuz persicae Sulzer, Aphis fabae Scopoli, Phorodon cannabis Passerini, P. humuli Schrank ve Aphis gossypii Glover (Hemiptera: Aphididae)], Thripsler [Thrips tabaci Lind ve Frankniella occidentalis Pergande (Thysanoptera: Thripidae)], Kenevirde zararlı akarlar [Tetranychus urticae Koch ve T. cinnabarinus Boisduval (Acari: Tetranychidae)] gibi zararlıların yanı sıra, Sümüklü böcek ve salyangoz, memeliler ve kuşlar gibi genel zararlılar da vardır. Kenevir zararlıları ile entegre mücadele anlayışı ile hareket etmek, kenevir ekosistemindeki faydalı böcekleri ve doğal dengenin korunmasını sağlayacaktır. Entegre mücadele anlayışı, zararlı sorununun devam etmesini engelleyecektir. Yapılan bu derlemede dünyada kenevirde zarar yapan türler ve faydalı böcekler listelenmiştir. Ayrıca ülkemizde bulunan potansiyel kenevir zararlılarının entegre mücadele kapsamında kontrol yöntemleri ortaya konmuştur.
Bazı Muscari Mill. (Asparagaceae) Türleri Üzerine Karşılaştırmalı Morfolojik, Anatomik ve Palinolojik Çalışmalar
Authors: İLÇİM Ahmet , KARATAŞ Halil , KARAHAN Faruk
Published: May 2020

Bu çalışmada, Hatay’da doğal yayılış gösteren Muscari inconstrictum Rech. fil., M. comosum L., M. babachii Eken & Koyuncu ve M. neglectum Guss. türlerinin morfolojik, anatomik ve palinolojik özellikleri incelenmiştir. Morfolojik çalışmalarda soğan, yaprak, çiçek, meyve ve tohum gibi yapıların özellikleri incelenmiştir. Tohum özellikleri incelendiğinde tohum büyüklüklerinin farklı, tohum şekillerinin M. inconstrictum’da ovat-eliptik diğer türlerde sferoidal olarak ve yüzey şekilleri entire, rugose ve ribbed olarak belirlenmiştir. Palinolojik analiz sonuçları polenlerin apartürleri sulkat, polen tipi subprolate ve oblate (basık) şekilde ve retikulat-subraretikulat ornamentasyona sahip olduğunu göstermektedir. Anatomik çalışmalarda, türlerin kök, gövde ve yapraklarından parafin yöntemiyle enine kesitler alınmıştır. Hazırlanan preparatlar ışık mikroskobu altında fotoğraflanarak anatomik özellikleri belirlenmiştir.
Konteyner Terminallerinde Ağır Vasıta Park Sahası Kapasitesinin Simülasyon Yöntemi ile Optimizasyonu
Authors: YILDIRIM Mehmet Sinan , AYDIN Metin Mutlu , GÖKKUŞ Ümit
Published: May 2020

Konteyner terminalleri konteyner yüklerinin dağıtıldığı, toplandığı, ulaştırma türünün değiştirildiği yerlerdir ve ülkelerin dış ticaret performansı için önemli birer ulaştırma yapılarıdır. Günümüzde konteyner birim yükünün ve türler arası ulaştırma olanaklarının gelişmesi farklı ulaştırma türlerinin kombine bir şekilde kullanılabilmesinin önünü açmıştır. Bu durum kombine yük taşımacılığında avantaj sağlayan demiryolu taşımacılığının önemini giderek daha da arttırmıştır. Bu gelişmelere rağmen bazı ülkelerde demiryolu taşımacılığı yerine karayolu taşımacılığının halen etkin bir şekilde kullanıldığı görülmektedir. Diğer ulaştırma türleri ile karşılaştırıldığında konteyner terminallerinde karayolu taşımacılığı, bağlantılı karayolu altyapısında trafik sıkışıklığı, gürültü kirliliği, hava kirliliği vb. trafik ve çevre sorunlarına yol açmaktadır. Bu problem özellikle limanların çevresinde ağır vasıtaların park etme arayışları ve konteyner terminallerinde yük almak ya da boşaltmak için kuyruğa girmesiyle ciddi trafik ve çevresel problemlere neden olabilmektedir. Bu çalışmada belirtilen bu problemlerin çözümünde katkı sağlayabilmek amacıyla tipik bir konteyner terminali için ağır vasıta park sahası tasarımı gerçekleştirilmiştir. Saha kapasitesi için öncül bir kapasite optimizasyon çalışması, simülasyon modeli desteği ile yapılmıştır. Park saha kapasitesinin belirlenmesi için bir maliyet optimizasyonu yöntemi geliştirilerek, simülasyon model çıktıları ile kapasite optimizasyonu hedeflenmiştir. Çalışma sonucunda simülasyon optimizasyon yöntemi ile ağır vasıtaların yol ağlarında ve limanlarda beklemelerini önleyebilmek amacıyla optimum park sahası kapasitesinin belirlenebildiği ortaya konmuştur.
Evaluation of Some Physicochemical Parameters of Cevdet Dündar Pond (Yozgat/Turkey) Based on Bathymetric Map and Field Measurements
Authors: ERDOĞAN Şeyda , ÖZEN Arda , AKIN Şenol , EDİŞ Semih
Published: May 2020

Cevdet Dündar pond is located between the Fatih Nature Park and Yozgat Pine Grove National Park boundaries in Yozgat where semi-arid climate prevails with cold-rainy winters and arid-dry summers. The pond serves as a main water source for local communities. However, limnologic studies have not been conducted in the pond until today. The aim of this study is to create a bathymetric map of the pond in order to determine usable volume, depth change and to conduct first preliminary limnologic study in the pond to create the necessary sub-study for future sustainability studies. Moreover, some physicochemical parameters (water temperature (°C), pH, dissolved oxygen (mg), saturated oxygen (%), conductivity (μS/cm), salinity (‰) and total dissolved solid (mg L-1)) were measured from the whole water column at 50 cm intervals for 11 months. Accordingly, a bathymetric map of the lake was created, total area and volume of the pond were calculated. According to results the maximum area of the pond was 29 536.7 m2 and volume of the pond was 225 209.59 m3. During the study period average dissolved oxygen and saturated oxygen were determined as 6.7 mg and % 72.4. While highest average water temperature was measured during the August (2018) with 17.7 °C, lowest temperature was recorded during March as 5.7 °C. Thermal stratification was observed in summer months. The difference in water temperature between the epilimnion and hypolimnion was changed between 10 -13 ℃. Anaerobic conditions were also measured in hypolimnion layer. Average of monthly pH, conductivity, salinity and total dissolved solid were calculated as 7.7 mg L-1, 176.7 μS/cm, 0.08 ppm, 88.1 respectively.
Türkiye’de Nükleer Enerji Öncesi Trabzon İlinde Yaşayan Bazı İnsanlarda Trityum Konsantrasyonları
Authors: DİZMAN Serdar
Published: May 2020

Çalışma, Türkiye’nin kuzey doğusunda ve Karadeniz sahilinde yer alan Trabzon ilinde gerçekleştirilmiştir. Trabzon ilinin merkez ilçesinde 317 520 kişi yaşamaktadır. İnsanlardaki trityum konsantrasyonu, idrarlarındaki trityum aktivite konsantrasyonunun ölçülmesi suretiyle belirlenir. Bu kapsamda, Türkiye İstatistik Kurumu tarafından belirlenen hanelerde yaşayan 100 katılımcıdan idrar örnekleri alındı ve analiz edildi. Örneklerdeki trityum konsantrasyonları sıvı sintilasyon sayacı (LSC) ile belirlendi. Katılımcıların yaşı 18 ile 65 arasında değişmekte olup, yaş ortalaması 34.99’dur. Katılımcıların idrar örneklerinde ortalama trityum konsantrasyonu 13.37 ± 2.33 Bq L-1, maksimum konsantrasyon 33.23 Bq L-1 olarak bulundu. Uygulanan metodun MDA’sı 2.59 Bq L-1 olarak belirlendi. 23 örneğin (%23) trityum konsantrasyonu MDA’nın altında tespit edildi. Kadın ve erkeklerin idrar örneklerinde ortalama trityum konsantrasyonları sırasıyla 13.45 ± 2.39 Bq L-1 ve 13.32 ± 2.30 Bq L-1 olarak bulundu. Ayrıca, yıllık etkin doz oranları kadınlar için 11.13 nSv ve erkekler için 12.78 nSv olarak hesaplandı. Hesaplanan bu yıllık etkin doz oranları, Uluslararası Radyasyondan Korunma Komitesi (ICRP) tarafından önerilen değerlerden oldukça düşüktür.
Kadmiyum Stresi Altındaki Çilek (Fragaria x ananassa “Camarosa”) Bitkisinde Metil Jasmonat Uygulamalarının Bazı Büyüme Parametreleri Üzerine Etkileri
Authors: MURADOĞLU Ferhad , BAYTIN Rana , BAŞAK İbrahim , Akkuş Gökhan
Published: May 2020

Ağır metaller bitki için temel besin maddesi olmayan genellikle toksik etkiye sahip elementlerdirler. Kadmiyum bitki büyüme ve gelişmesini ciddi sınırlandırabilen ve çevreye olumsuz etkileri olduğu iyi bilinen en önemli toksik metallerden biridir. Bitkisel hormonlar, bitki bünyesindeki hormonların üretim, dağıtım veya sinyal çevrimini değiştirerek çevre koşullarına karşı değişen tepkiyi vermesi yanında bitki büyüme ve gelişmesini düzenleyen küçük moleküllerdirler. Jasmonatlar (JAs) birçok ileri bitki süreçlerini düzenlemekte ve olumsuz çevreresel stres faktörlerine karşı bitki savunma mekanizmasında aktif bir rol oynamaktadırlar. Bu çalışmada, ağır metal (kadmiyum) stresinde dışsal metil jasmonat (MeJa) uygulamalarının çilek (Camarosa ) bitkisinde bazı büyüme parametreleri üzerine etkilerinin belirlenmesi hedeflenmiştir. Çalışmada kadmiyum konsantrasyonun artışına paralel olarak çilek bitkisinde incelenen büyüme parametrelerinde düşüş belirlenmiştir. Bununla birlikte, metil jasmonat uygulamalarının kadmiyum toksitesini hafiflettiği ve uygulama dozuna bağlı olarak çilek bitkisinde kök sayısı, kök ağırlığı, gövde ağırlığı ve yaprak alanında artış sağladığı belirlenmiştir. Elde edilen sonuçlar kadmiyum uygulamalarının çilek bitkisinin büyümesi üzerine olumsuz etkilerinin olduğu ve metil jasmonat uygulamalarının ise kadmiyum stresinin azaltılmasında önemli bir rol oynadığı belirlenmiştir.
Üniversite Öğrencilerinde Kahvaltı Yapma Alışkanlığının Saptanması ve Çözüm Önerileri
Authors: ÇETİK YILDIZ Songül
Published: May 2020

Kahvaltı, yeterli ve dengeli beslenmede günün en önemli öğünü olarak büyük öneme sahiptir. Kahvaltının yapılmaması, yetersiz yapılması veya atlanması durumunda dikkat-algılama bozukluğu, fiziksel-zihinsel yorgunluk gibi sorunlar meydana gelir ve eğitim-öğretimde başarı azalarak nitelikli bireylerin yetişmesi engellenir. Bu çalışma, üniversite öğrencilerinin kahvaltı yapma alışkanlıklarını belirlemek için planlanıp ve uygulanmıştır. Bu amaçla, 2015-2019 öğretim yılında Mardin’de okuyan 18 yaş ve üzeri üniversite öğrencilerinin kahvaltı yapma alışkanlıkları anket yöntemi ile saptanmıştır. Çalışmaya % 62.0’si erkek ve % 38.0’i kadın olmak üzere 1200 kişi dahil edilmiştir. Çalışmaya katılan öğrencilerin yaş ortalaması kadınlarda 22.1, erkeklerde 23 yıl, eğitim süreleri ortalaması ise kadınlarda 15.2, erkeklerde 16.3 yıldır. Öğrencilerin ortalama boy uzunluğu, kadınlarda 154.4, erkeklerde ise 172.2 cm, vücut ağırlığı değerleri kadınlarda 56.2 kg, erkeklerde 79.1 kg’dır. Üniversite öğrencilerinin öğün atlama durumu incelendiğinde en çok atlanan öğünün (% 47.9) kahvaltı olduğu görülmüştür. Öğün atlamalarının sebebi, zaman yetersizliği (% 37.0) ve sabah geç kalkma (% 24.0) ve kahvaltı yapma alışkanlığın olmaması (% 19.0) olarak ifade edilmiştir. Kahvaltıda içecek tüketimi incelendiğinde, en fazla çayın tercih edildiği belirlenmiştir. Bu çalışmanın sonuçları üniversite öğrencilerin kahvaltı yapma alışkanlıklarının yetersiz olduğu göstermektedir.
Dört Serbestlik Dereceli Bir İnsansız Sualtı Aracının 3 Boyutlu Bilgisayar Benzetimi
Authors: YILMAZ Serhat , KILCI Sadettin Burak
Published: May 2020

Torpido tipi insansız sualtı araçları (İSA) günümüzde, sualtı hareketlerinin izlenmesi, okyanus dibi sıcaklık haritalarının çıkarılması, tuzlu su katmanlarının belirlenmesi gibi uzun menzilli görevleri başarı ile yerine getirmektedir. Kayıp arama ve kurtarma, sünger toplama, mayın temizleme, gemi altı bakımı, gemi altı hasarlarının görüntülenmesine yönelik uzman incelemesi işlemleri, tehlikeli derinliklerde görüntü alma, batıkların incelenmesi gibi detaylı bölgesel araştırmalar ise modüler tip İSA’ları ile sağlanmaktadır. Benzer şekilde, İSA’nın sahil güvenliğini sağlama, askeri birtakım görevleri yerine getirme, baraj tabanlarının temizlenmesi, göl, tatlı su kaynakları, sualtı mağaraları, aktif sualtı volkanları, akarsuların denizlere döküldüğü akarsu ağızları gibi alıcı su ortamlarının düzenli kirlilik analizi ve kirlilik haritalarının çıkarılması gibi toplumsal ve doğal yaşamın güvenliğine yönelik önleyici görevleri bulunmaktadır. Meksika Körfezi’nde yaşanan ham petrol sızıntısının yol açtığı çevre felaketi gözleri sondaj platformlarına çevirmiştir. Platform ayaklarının bakımı, boru hatlarının izlenmesi, sızıntı tespiti, su altında kaynak işlemleri gibi tehlikeli işlemler uzaktan kumandalı İSA ile yapılmaktadır. Bu çalışma, 4 serbestlik derecesine sahip bir İSA’nın bilgisayar destekli 3 boyutlu (3D) modellemesini ve model üzerindeki benzetim uygulamalarını ele almaktadır. Benzetim programları sayesinde, yüksek maliyet ve zaman gerektiren testleri en aza indirgemek, hatalı tasarımların yol açacağı hasar ve kayıpların önüne geçmek mümkündür. İSA ve üzerlerindeki ekipmanlar yüksek maliyetlidir. Bu nedenle kullanıcıların, deniz ortamında araç kullanmadan önce simülatörde eğitime almaları gerekir. İSA’nın modellenmesi ve benzetimi üzerine geliştirilen yazılımlar, sualtı araştırmalarındaki başarımı arttırmada önemli bir rol oynayacaktır.
Influence of in vitro Micropropagation Growth Conditions on Stomatal and Morphological Characteristics of Mature Pistacia vera L.
Authors: AYAZ TİLKAT Emine , HOŞGÖREN Hülya , KAPLAN Alevcan , TİLKAT Engin
Published: May 2020

This research was conducted to reveal the stomatal anatomy, stomatal index and water loss (%) of mature pistachio leaves as well as the leaves of different phases (multiplication, rooting, hardening and regenerated plant) of micropropagation of mature pistachio trees obtained from the in vitro. Microscopic observations on surfaces of these leaves showed variety from elliptical to ovate stomata with length of 0.81-2.02 μm and width of 1.58-3.80 μm. An increase in stomatal index (SI) in the leaves of plants grown in vitro was observed most specifically in the hardening phase. (17.49±0.04). The stomatal index declined in the leaves of plantlets transferred to in vivo conditions subsequent to the hardening phase. In order to measure water loss, leaves obtained from all types of samples were dried in the oven between 30 minutes and 2 hours and weighed. The percent water loss of in vitro leaves of multiplication phase was greater than the other phases. The stomatal differentation was found to be influenced by the different hardening regimes applied. Hardening by covering the pots with polyethylene bags improved the survival rate. This study indicates that optmization of in vitro micropropagation stages is necessary to avoid transplantation stress.
Farklı Kotlu Kollara Sahip Hemzemin Dönel Kavşaklardaki Kazaların Analizi: Atatürk Üniversitesi Kavşağı Örneği
Authors: ATALAY Ahmet , KISAOĞLU Serdar
Published: May 2020

Bu çalışmanın amacı, farklı kotlu kollara sahip hemzemin dönel kavşaklarda meydana gelen kazaların, kaza şiddetini etki eden faktörleri araştırmaktır. Atatürk Üniversitesi kavşağı örneğinde üç farklı veri seti oluşturularak, lojistik regresyon analizi yöntemi ile üç farklı istatistiksel modelleme yapılmıştır. İstatistiksel modellerde bağımlı değişken olarak kaza şiddeti ve kazaya karışan araç sayısı kullanılmıştır. Bağımsız değişken olarak yol yüzey durumu (kuru- ıslak), gün durumu (gündüz-gece), saat dilimi (9:00-14:59, 15:00-20:59, 21:00 2:59, 3:00-8:59) ve kazanın meydana geldiği gün (pazartesi, salı, çarşamba, perşembe, cuma, cumartesi, pazar) değişkeni kullanılmıştır. Çalışma sonunda yüzey durumunun kaza şiddetinin artmasında anlamlı bir etkisinin olmadığı, gün durumu ve saat dilimi değişkeninin, kazanın şiddeti üzerinde etkili olduğu ve Pazar günü olan kazaların şiddeti diğer günlerden fazla olduğu belirlenmiştir. Ayrıca kavşak kollarındaki mutlak eğimin çoklu kazalar üzerinde önemli etkiye sahip olduğu tespit edilmiştir.