Sandwich Beams with Arbitrary Boundary Conditions

1975 ◽  
Vol 97 (3) ◽  
pp. 873-880 ◽  
Author(s):  
Dusan Krajcinovic
Keyword(s):  
Efficient Method ◽  
Present Method ◽  
Sandwich Beams ◽  
Cross Sectional ◽  
Arbitrary Boundary ◽  
Variational Equations ◽  
Material Parameters ◽  
Wide Range ◽  
Derived Set ◽  
Beam Bending

Presented is a practical and efficient method for the analysis of arbitrarily supported sandwich beams. Based on the previously derived set of governing variational equations, the present method utilizes familiar transfer matrix procedure. Final solutions for the displacement and stresses consist of two terms reflecting correspondingly the conventional (solid) beam bending and the cross-sectional distortion. The proposed method is illustrated in a few examples and the results are plotted for a wide range of geometric and material parameters.

scholarly journals A Unified Solution for the Vibration Analysis of Lattice Sandwich Beams with General Elastic Supports

2021 ◽  
Vol 11 (19) ◽  
pp. 9141
Author(s):  
Yeqing Jin ◽  
Ruiping Yang ◽  
Hengxu Liu ◽  
Haiwei Xu ◽  
Hailong Chen
Keyword(s):  
Free Vibration ◽  
Boundary Conditions ◽  
Present Method ◽  
Displacement Function ◽  
Vibration Characteristics ◽  
Homogeneous Layer ◽  
Sandwich Beams ◽  
Arbitrary Boundary ◽  
Elastic Supports ◽  
Various Boundary Conditions

Free vibration analyses of lattice sandwich beams with general elastic supports have rarely been discussed in this field’s literature. In this paper, a unified method is proposed to study the free vibration characteristics of lattice sandwich beams under various boundary conditions. The proposed method is to convert the three truss cores of lattice sandwich beams into an equivalent homogeneous layer and introduce two different types of constraint springs to simulate the general elastic support boundary at both ends of lattice sandwich beams. By changing the rigidity of the boundary restraint spring, various boundary conditions can be easily obtained without modifying the solving algorithm and solving process. In order to overcome all the discontinuities or jumps associated with the elastic boundary support conditions, the displacement function of lattice sandwich beams is usually obtained as an improved Fourier cosine series along with four sine terms. On this basis, the unknown series coefficients of the displacement function are treated as the generalized coordinates and solved using the Rayleigh–Ritz method. The correctness of the present method is verified through comparison with existing literature. The calculation results of the present method are highly accurate, indicating that the present method is suitable for analyzing the vibration characteristics of lattice sandwich beams with general elastic supports. In addition, the effects of beam length, panel thickness, core height, radius and truss inclination on the natural frequencies of lattice sandwich beams with arbitrary boundary conditions have been discussed in this paper.

A Cross Sectional Survey of Chicken Astroviruses Antibody in Broiler and Sonali (Cross-Bred) Chickens in Selected Areas in Bangladesh

2020 ◽  
Vol 43 (1) ◽  
pp. 75-80
Author(s):  
Md Zulfekar Ali ◽  
Mohammad Moktader Moula ◽  
Zafar Ahmed Bhuiyan ◽  
Muhammad Tariq Javed
Keyword(s):  
Age Groups ◽  
Winter Season ◽  
Cross Sectional Survey ◽  
Cross Sectional ◽  
Blood Samples ◽  
Elisa Kit ◽  
Published Report ◽  
Poultry Birds ◽  
Wide Range ◽  
Group B

AbstractChicken astroviruses (CAstV) are enteric viruses of poultry causing gastroenteritis, malabsorption, gout and white chick disease commonly known as runting-stunting syndrome (RSS). It can affect the wide range of poultry birds, especially chicken, turkey and duck worldwide. To our best knowledge there is no published report on presence of antibodies against CAstV in Bangladesh. Therefore, the study aimed to detect the presence of CAstV antibodies in broilers and sonali chickens (a cross-bread) in Bangladesh through a cross-sectional survey. A total of 454 blood samples from 66 flocks of broiler (n=343) and sonali chickens (n=111) of different ages were obtained during 2017 from four districts. The birds were healthy but were not vaccinated against CAstV. The samples were tested for specific antibodies against CAstV Group B by using commercially available ELISA kit. Overall, 16.74% (76/454) samples and 34.84% (23/66) flocks were positive for CAstV antibodies. The seroprevalence of CAstV was significantly (p=0.001) higher in sonali chickens (36.96%) than broiler (10.20%), while it was significantly higher (p=0.001) in birds of Bogura district (36.94%) than the other three districts. Regarding the age groups, seroprevalence was insignificantly (p=0.192) higher in sonali chicken before laying age (45%) than during laying age (27.45%). Regarding the seasons, CAstV infection was prevalent significantly (p=0.001) higher in winter season. Thus, the present study indicated the presence of CAstV in poultry in Bangladesh, so further studies are required to find out the magnitude of the problem in the country.

Celiac Disease in Kosovar Albanian Children: Evaluation of Clinical Features and Diagnosis

2020 ◽  
Vol 16 (3) ◽  
pp. 241-247
Author(s):  
Atifete Ramosaj-Morina ◽  
Alije Keka-Sylaj ◽  
Arbana Baloku Zejnullahu ◽  
Lidvana Spahiu ◽  
Virgjina Hasbahta ◽  
...  
Keyword(s):  
Celiac Disease ◽  
Disease Onset ◽  
Clinical Manifestations ◽  
Gastrointestinal Symptoms ◽  
Dominant Mode ◽  
Primary School Children ◽  
Cross Sectional ◽  
Classical Form ◽  
Wide Range ◽  
The Mean

Background: Celiac disease is an immune-mediated disorder characterized by variable clinical manifestations, specific antibodies, HLA-DQ2/DQ8 haplotypes, and enteropathy. Objectives: The aim of this study was to present the clinical spectrum and patterns of celiac disease in Kosovar Albanian children. Methods: A cross-sectional retrospective study was performed with Albanian children aged 0-18 years, treated for celiac disease in the Pediatric Clinic, University Clinical Center of Kosovo from 2005 to 2016. Results: During the study period, 63 children were treated for celiac disease. The mean age at diagnosis was 5.5 years (SD ± 3.31). The mean age at celiac disease onset was 3.3 years (SD ± 2.02), while the mean delay from the first symptoms indicative of celiac disease to diagnosis was 2.2 years (SD ± 2.09). More than 70% of the patients were diagnosed in the first 7 years of life, mainly presented with gastrointestinal symptoms, while primary school children and adolescents mostly showed atypical symptoms (p<0.001). The classical form of celiac disease occurred in 78% of the cases. Sixty (95%) patients carried HLA-DQ2.5, DQ2.2 and/or HLA-DQ8 heterodimers, and only three of them tested negative. Conclusions: Kosovo, as the majority of developing countries, is still facing the classical form of celiac disease as the dominant mode of presentation; as a result, most children with other forms of the celiac disease remain undiagnosed. : Physicians should be aware of the wide range of clinical presentations and utilize low testing thresholds in order to prevent potential long-term problems associated with untreated celiac disease.

Soames' & Southam's Oral Pathology

2018 ◽  
Author(s):  
Max Robinson ◽  
Keith Hunter ◽  
Michael Pemberton ◽  
Philip Sloan
Keyword(s):  
Skin Diseases ◽  
Oral Pathology ◽  
Pathological Features ◽  
Oral Diseases ◽  
Oral Medicine ◽  
Cross Sectional ◽  
Facial Region ◽  
Wide Range ◽  
Cross Sectional Imaging ◽  
Key Aspects

A sound understanding of clinical oral pathology is essential if a dental clinician is to navigate successfully through clinical guidelines, make timely referrals to specialists, and provide good care for patients. This new edition of Soames' & Southam's Oral Pathology provides a clear and friendly guide for students, practitioners, and the whole dental team. Thoroughly updated for today's clinical practice, this textbook covers 'must-know' oral pathology and integrates key aspects of oral medicine. It begins by explaining the principles of clinical assessment, the synthesis of a differential diagnosis, and the selection of further investigations including laboratory tests. Ten chapters bring this theory to life by looking at the clinical and pathological features of a wide range of common oral diseases including oral cancer, salivary gland disorders, and diseases of the jaws. Two new chapters address skin diseases affecting the oro-facial region and neck lumps. A final chapter highlights the importance of clinical oral pathology in the context of systemic human disease. New radiology content includes examples of cross-sectional imaging. Photomicrographs have been replaced with carefully selected images to illustrate key pathological features. Each chapter includes key points boxes and tables to aid learning. Written by experts in both oral pathology and oral medicine, this new edition is a must-have for dentistry students, and those working in the field, providing current and trustworthy information.

scholarly journals Oxidative status in plasma, urine and saliva of girls with anorexia nervosa and healthy controls: a cross-sectional study

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Alexandra Gaál Kovalčíková ◽  
Ľubica Tichá ◽  
Katarína Šebeková ◽  
Peter Celec ◽  
Alžbeta Čagalová ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Anorexia Nervosa ◽  
Redox Homeostasis ◽  
Oxidative Status ◽  
Carbonyl Stress ◽  
Healthy Controls ◽  
Psychosomatic Disorder ◽  
Cross Sectional ◽  
Wide Range ◽  
Markers Of Oxidative Stress

Abstract Background Anorexia nervosa (AN) is a serious psychosomatic disorder with unclear pathomechanisms. Metabolic dysregulation is associated with disruption of redox homeostasis that might play a pivotal role in the development of AN. The aim of our study was to assess oxidative status and carbonyl stress in plasma, urine and saliva of patients with AN and healthy controls. Methods Plasma, spot urine, and saliva were collected from 111 girls with AN (aged from 10 to 18 years) and from 29 age-matched controls. Markers of oxidative stress and antioxidant status were measured using spectrophotometric and fluorometric methods. Results Plasma advanced oxidation protein products (AOPP) and advanced glycation end products (AGEs) were significantly higher in patients with AN than in healthy controls (by 96, and 82%, respectively). Accordingly, urinary concentrations of AOPP and fructosamines and salivary concentrations of AGEs were higher in girls with AN compared with controls (by 250, and 41% in urine; by 92% in saliva, respectively). Concentrations of thiobarbituric acid reactive substances (TBARS) in saliva were 3-times higher in the patients with AN than in the controls. Overall antioxidants were lower in plasma of girls with AN compared to the controls, as shown by total antioxidant capacity and ratio of reduced and oxidized glutathione (by 43, and 31%, respectively). Conclusions This is the first study assessing wide range of markers of oxidative status in plasma, urine and saliva of the patients with AN. We showed that both, higher levels of markers of oxidative stress and lower antioxidants play a role in redox disruption. Restoration of redox homeostasis might be of the clinical relevance

scholarly journals Kinematic Analysis of Lower Limb Joint Asymmetry during Gait in People with Multiple Sclerosis

Symmetry ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 598
Author(s):  
Massimiliano Pau ◽  
Bruno Leban ◽  
Michela Deidda ◽  
Federica Putzolu ◽  
Micaela Porta ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Lower Limb ◽  
Sagittal Plane ◽  
Cross Sectional Study ◽  
Camera Motion ◽  
Cross Sectional ◽  
Temporal Parameters ◽  
Wide Range ◽  
Edss Score ◽  
Spatio Temporal

The majority of people with Multiple Sclerosis (pwMS), report lower limb motor dysfunctions, which may relevantly affect postural control, gait and a wide range of activities of daily living. While it is quite common to observe a different impact of the disease on the two limbs (i.e., one of them is more affected), less clear are the effects of such asymmetry on gait performance. The present retrospective cross-sectional study aimed to characterize the magnitude of interlimb asymmetry in pwMS, particularly as regards the joint kinematics, using parameters derived from angle-angle diagrams. To this end, we analyzed gait patterns of 101 pwMS (55 women, 46 men, mean age 46.3, average Expanded Disability Status Scale (EDSS) score 3.5, range 1–6.5) and 81 unaffected individuals age- and sex-matched who underwent 3D computerized gait analysis carried out using an eight-camera motion capture system. Spatio-temporal parameters and kinematics in the sagittal plane at hip, knee and ankle joints were considered for the analysis. The angular trends of left and right sides were processed to build synchronized angle–angle diagrams (cyclograms) for each joint, and symmetry was assessed by computing several geometrical features such as area, orientation and Trend Symmetry. Based on cyclogram orientation and Trend Symmetry, the results show that pwMS exhibit significantly greater asymmetry in all three joints with respect to unaffected individuals. In particular, orientation values were as follows: 5.1 of pwMS vs. 1.6 of unaffected individuals at hip joint, 7.0 vs. 1.5 at knee and 6.4 vs. 3.0 at ankle (p < 0.001 in all cases), while for Trend Symmetry we obtained at hip 1.7 of pwMS vs. 0.3 of unaffected individuals, 4.2 vs. 0.5 at knee and 8.5 vs. 1.5 at ankle (p < 0.001 in all cases). Moreover, the same parameters were sensitive enough to discriminate individuals of different disability levels. With few exceptions, all the calculated symmetry parameters were found significantly correlated with the main spatio-temporal parameters of gait and the EDSS score. In particular, large correlations were detected between Trend Symmetry and gait speed (with rho values in the range of –0.58 to –0.63 depending on the considered joint, p < 0.001) and between Trend Symmetry and EDSS score (rho = 0.62 to 0.69, p < 0.001). Such results suggest not only that MS is associated with significantly marked interlimb asymmetry during gait but also that such asymmetry worsens as the disease progresses and that it has a relevant impact on gait performances.

scholarly journals Minimum acceptable diet among children aged 6–23 months in South Kivu, Democratic Republic of Congo: a community-based cross-sectional study

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Richard Mbusa Kambale ◽  
Gaylord Amani Ngaboyeka ◽  
Joe Bwija Kasengi ◽  
Sarah Niyitegeka ◽  
Boss Rutakaza Cinkenye ◽  
...  
Keyword(s):  
Democratic Republic ◽  
Democratic Republic Of Congo ◽  
Feeding Practices ◽  
Cross Sectional Study ◽  
Sectional Study ◽  
Community Based ◽  
Cross Sectional ◽  
Republic Of Congo ◽  
Wide Range ◽  
South Kivu

Abstract Background Suboptimal child nutrition remains the main factor underlying child undernutrition in Democratic Republic of Congo (DRC). This study aimed to assess the prevalence of minimum acceptable diet and associated factors among children aged 6–23 months old. Methods Community-based cross-sectional study including 742 mothers with children aged 6–23 months old was conducted in 2 Health Zones of South Kivu, Eastern DRC. WHO indicators of Infant and Young Child Feeding (IYCF) regarding complementary feeding practices were used. Logistic regression analysis was used to quantify the association between sociodemographic indicators and adequate minimum acceptable diet for both univariate and multivariate analysis. Results Overall, 33% of infants had minimum acceptable diet. After controlling for a wide range of covariates, residence urban area (AOR 2.39; 95% CI 1.43, 3.85), attendance postnatal care (AOR 1.68; 95% CI 1.12, 2.97), education status of mother (AOR 1.83; 95% CI 1.20, 2.77) and household socioeconomic status (AOR 1.72; 95% CI 1.14, 2.59) were factors positively associated with minimum acceptable diet. Conclusion Actions targeting these factors are expected to improve infant feeding practices in South Kivu.

scholarly journals Patterns of use, effectiveness and safety of gadolinium contrast agents: a European prospective cross-sectional multicentre observational study

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Jarl Åsbjørn Jakobsen ◽  
Carlo Cosimo Quattrocchi ◽  
Frank H. H. Müller ◽  
Olivier Outteryck ◽  
Andrés Alcázar ◽  
...  
Keyword(s):  
Image Quality ◽  
Observational Study ◽  
Contrast Agents ◽  
Marketing Authorisation ◽  
Safety Data ◽  
Radiological Diagnosis ◽  
Routine Practice ◽  
Diagnostic Confidence ◽  
Cross Sectional ◽  
Wide Range

Abstract Background The EU gadolinium-based contrast agents (GBCA) market has changed in recent years due to the European Medicines Agency decision to suspend the marketing authorisation of linear GBCA and the marketing authorisation of new generic macrocyclic GBCA. The study aims to understand the patterns of (GBCA) use, and to study the effectiveness and safety of GBCA in routine practice across Europe. Methods Prospective, cross-sectional, multicentre, observational study in patients undergoing contrast-enhanced magnetic resonance. Reported usage patterns included indication, referral and examination details. Assessment of effectiveness included changes in radiological diagnosis, diagnostic confidence and image quality. Safety data were collected by spontaneous patient adverse event (AE) reporting. Results 2118 patients were included from 8 centres across 5 European countries between December 2018 and November 2019. Clariscan, Dotarem (gadoteric acid), Gadovist (gadobutrol) and ProHance (gadoteridol) were utilised in 1513 (71.4%), 356 (16.8%), 237 (11.2%) and 12 (0.6%) patients, respectively. Most were performed in CNS-related indications (46.2%). Mean GBCA doses were 0.10 mmol/kg body weight, except for Gadovist (mean 0.12 mmol/kg). GBCA use increased confidence in diagnosis in 96.2% of examinations and resulted in a change in radiological diagnosis in 73.9% of patients. Image quality was considered excellent or good in 96.1% of patients and across all GBCA. Four patients reported AEs (0.19%), with only 1 (0.05%) considered serious. Conclusions This European study confirmed that GBCAs are used appropriately in Europe for a wide range of indications. The study demonstrated a significant increase in diagnostic confidence after GBCA use and confirmed the good safety profile of GBCAs, with comparable results for all agents used.

scholarly journals Allergic rhinitis, asthma and laryngopharyngeal reflux disease: a cross-sectional study on their reciprocal relations

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ameer Kakaje ◽  
Mohammad Marwan Alhalabi ◽  
Ayham Alyousbashi ◽  
Ayham Ghareeb
Keyword(s):  
Allergic Rhinitis ◽  
Reflux Disease ◽  
Medical Condition ◽  
Laryngopharyngeal Reflux ◽  
Cross Sectional Study ◽  
Sectional Study ◽  
Reflux Symptom Index ◽  
Symptom Index ◽  
Cross Sectional ◽  
Wide Range

AbstractAllergic rhinitis (AR) is a common medical condition worldwide. It is an inflammation in the nasal mucosa due to allergen exposure throughout the year. Laryngopharyngeal reflux (LPR) is another medical condition that can overlap with AR. LPR can be considered an extra oesophageal manifestation of gastro-oesophageal reflux disease (GORD) or a different entity. Its diagnosis imposes a real challenge as it has a wide range of unspecific symptoms. Although AR and LPR are not life-threatening, they can severely affect the quality of life for years and cause substantial distress. Moreover, having AR is associated with having asthma which is also in turn associated with GORD. This is a cross-sectional study which used surveys distributed online on Social Media and targeted people across Syria. All participants who responded to the key questions were included. Reflux symptom index (RSI) was used for LPR, and score for allergic rhinitis (SFAR) was used for AR. Demographic questions and whether the participant had asthma were also included in the survey. We found that there was an association between the symptoms of LPR and AR p < 0.0001 (OR, 2.592; 95% CI 1.846–3.639), and their scores were significantly correlated (r = 0.334). Having asthma was associated with LPR symptoms p = 0.0002 (OR 3.096; 95% CI 1.665–5.759) and AR p < 0.0001 (OR 6.772; 95% CI 2.823–16.248). We concluded that there was a significant association between having LPR, AR, and asthma. We need more studies to distinguish between their common symptoms and aetiologies.

scholarly journals Measuring Vulnerability to Multidimensional Poverty

2019 ◽  
Vol 148 (1) ◽  
pp. 67-103 ◽  
Author(s):  
Mauricio Gallardo
Keyword(s):  
Multidimensional Poverty ◽  
Risk Behaviour ◽  
Poverty Measurement ◽  
Multidimensional Space ◽  
Poverty Index ◽  
Cross Sectional ◽  
Multidimensional Poverty Index ◽  
Wide Range ◽  
Vulnerability Indicators ◽  
Vulnerability To Poverty

Abstract A method to measure vulnerability to multidimensional poverty is proposed under a mean–risk behaviour approach. We extend the unidimensional downside mean–semideviation measurement of vulnerability to poverty towards the multidimensional space by incorporating this approach into Alkire and Foster’s multidimensional counting framework. The new approach is called the vulnerability to multidimensional poverty index (VMPI), alluding to the fact that it can be used to assess vulnerability to poverty measured by the multidimensional poverty index (MPI). The proposed family of vulnerability indicators can be estimated using cross-sectional data and can include both binary and metric welfare indicators. It is flexible enough to be applied for measuring vulnerability in a wide range of MPI designs, including the Global MPI. An empirical application of the VMPI and its related indicators is illustrated using the official MPI of Chile as the reference poverty measurement. The estimates are performed using the National Socioeconomic Characterisation Survey (CASEN) for the year 2017.

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