Maximum Stresses and Flexibility Factors of Smooth Pipe Bends With Tangent Pipe Terminations Under In-Plane Bending

1983 ◽  
Vol 105 (4) ◽  
pp. 329-336 ◽  
Author(s):  
G. Thomson ◽  
J. Spence
Keyword(s):  
Elastic Behavior ◽  
Constant Thickness ◽  
Recent Experimental Data ◽  
Cross Sectional ◽  
Linear Elastic ◽  
Total Potential ◽  
Wide Range ◽  
Theoretical Predictions ◽  
Plane Bending ◽  
Minimum Total Potential Energy

A theoretical solution is presented for the in-plane bending, linear elastic behavior of smooth, circular cross-sectional constant thickness pipe bends with connected tangent pipes of similar section. The analytical method employs the theorem of minimum total potential energy with suitable kinematically admissible displacements. Integration and minimization is performed numerically. Results are given for bend flexibilities and peak stresses covering a wide range of practical geometries. These are compared with other theoretical predictions and finite element results as well as with some recent experimental data.

Stationary Creep Stresses for Elliptical Cross-Sectional Pipe Bends Subject to In-Plane Bending

1974 ◽  
Vol 96 (3) ◽  
pp. 162-170 ◽  
Author(s):  
J. Spence
Keyword(s):  
Elastic Beam ◽  
Constitutive Law ◽  
Constant Thickness ◽  
Straight Tube ◽  
Cross Sectional ◽  
Elliptical Cross ◽  
Curved Pipe ◽  
Linear Elastic ◽  
Plane Bending ◽  
Stationary Creep

A theoretical analysis is presented which allows the determination of the stationary creep stresses acting in a smooth curved pipe of initially elliptical cross section when subject to in-plane bending. The bend is assumed to be of constant thickness and “thin” compared with its cross-sectional axes. The analysis is based on an energy approach and uses a simple power-type creep constitutive law. Results are presented in nondimensional fashion in terms of the maximum linear elastic beam bending stress in a straight tube. A large range of possible geometries is covered.

Type 1 energy analysis for the creep of smooth circular pipe bends under combined in-plane bending and internal pressure

1977 ◽  
Vol 12 (1) ◽  
pp. 1-7 ◽  
Author(s):  
J Spence
Keyword(s):  
Internal Pressure ◽  
Creep Behaviour ◽  
Constitutive Relationship ◽  
Constant Thickness ◽  
Pipe Bend ◽  
Curved Pipe ◽  
Linear Elastic ◽  
Special Cases ◽  
Plane Bending

Many pipeline systems, in addition to catering for thermal expansion conditions, have to carry internal pressure loading. An approximate theoretical analysis is given for the pure creep of a smooth curved pipe bend under fixed ratios of combined pressure and in-plane bending. The bend is circular in cross-section and of constant thickness. An energy method designated type 1, coupled with a simple n-power constitutive relationship, is used and implemented by direct minimization techniques. Selected deformation and stress results are presented as possible design factors for a number of the geometric and material parameters. For part of the geometric spectrum, large displacement effects are significant and lead to non-steady creep behaviour. Consequently there is not a direct analogy with elasticity, although linear elastic results can nevertheless be identified. Other special cases of loading or geometry are reducible from the general case.

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.

QCD at Fixed Order: Processes

2018 ◽  
Author(s):  
John Campbell ◽  
Joey Huston ◽  
Frank Krauss
Keyword(s):  
Hadron Collider ◽  
Detailed Comparison ◽  
Theoretical Description ◽  
Higgs Bosons ◽  
Final States ◽  
Collider Physics ◽  
Wide Range ◽  
Theoretical Predictions ◽  
Fixed Order ◽  
The Subject

At the core of any theoretical description of hadron collider physics is a fixed-order perturbative treatment of a hard scattering process. This chapter is devoted to a survey of fixed-order predictions for a wide range of Standard Model processes. These range from high cross-section processes such as jet production to much more elusive reactions, such as the production of Higgs bosons. Process by process, these sections illustrate how the techniques developed in Chapter 3 are applied to more complex final states and provide a summary of the fixed-order state-of-the-art. In each case, key theoretical predictions and ideas are identified that will be the subject of a detailed comparison with data in Chapters 8 and 9.

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.

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