362 research outputs found
Shear-lag analysis of a hybrid, unidirectional composite with fiber damage
Development of a method of analysis capable of predicting accurately the fracture behavior of unidirectional hybrid (buffer strip) composite laminates was studied. Three particular solutions are discussed in detail: broken fibers in a unidirectional half-plane; adjoined half planes of different fiber and matrix properties; and the solution of two half planes bounding a third distinct region of finite width. This finite width region represents a buffer strip and primary attention is given to the potential of this strip to arrest a crack that originates in one of the half planes. A materials modeling approach using the classical shear lag assumption to describe the stress transfer between fibers was analyzed. Explicit fiber and matrix properties of the three regions are retained, and changes in the laminate behavior as a function of the relative material properties, buffer strip width, and initial crack length are discussed
Analysis of a hybrid-undirectional buffer strip laminate
A method of analysis capable of predicting accurately the fracture behavior of a unidirectional composite laminate containing symmetrically placed buffer strips is presented. As an example, for a damaged graphite/epoxy laminate, the results demonstrate the manner in which to select the most efficient combination of buffer strip properties necessary to inhibit crack growth. Ultimate failure of the laminate after the arrest can occur under increasing load either by continued crack extension through the buffer strips or the crack can jump the buffer strips. For some typical hybrid materials it is found that a buffer strip spacing to width ratio of about four to one is the most efficient
Mathematical modeling of damage in unidirectional composites
A review of some approximate analytical models for damaged, fiber reinforced composite materials is presented. Using the classical shear lag stress displacement assumption, solutions are presented for a unidirectional laminate containing a notch, a rectangular cut-out, and a circular hole. The models account for longitudinal matrix yielding and splitting as well as transverse matrix yielding and fiber breakage. The constraining influence of a cover sheet on the unidirectional laminate is also modeled
Parents and Professionals Understanding of School Readiness for Children with Autism Spectrum Disorder: A Qualitative Analysis
BACKGROUND :
Occupational therapists frequently assist children to make the transition from preschool to school. This involves a ‘significant ecological shift’, with children having to negotiate increased academic and social demands, as well as physical changes in their learning environments. School readiness should be well understood for the successful transition to school & academic performance for all children, including children with special needs and also children with ASD.
OBJECTIVE :
The objective of this study was to identify the perspectives regarding school readiness among professionals and parents of children with ASD.
METHODOLOGY :
A qualitative research design was adopted for this study. A valid interview guide was prepared and was used to conduct the semi- structured interview with parents of children with Autism Spectrum Disorder (ASD) and professionals including occupational therapists, psychologists, special educators and primary school teachers. The participants (n= 100; 50 parents & 50 professionals) were selected on the basis of purposive sampling and interviewed. The data was analyzed using descriptive statistics as well as thematic analysis of the recorded interview.
RESULTS :
The major themes for school readiness that evolved from the present study were social skills, challenging behaviours, educational system, lack of training and knowledge by school teachers, functional communication and family support. 90% of parents reported that the challenging behaviours of the children was a barrier to school readiness. About 87.5% of the occupational therapists viewed the importance of the severity of the condition being a major component in determining the school readiness of children with autism. The physical development (87.5%) and fine motor development (75%) were rated as important for schooling of children with ASD in mainstream.
66.66% of the psychologists in this study view the importance of Government regulations, a crucial factor for sending a child with ASD to mainstream school.
CONCLUSION :
The present study contributed to the existing ASD literature by including multiple perspectives on school readiness of children with ASD. The results fostered the need of stimulating the parents and stakeholders to emphasize the importance of child- centered focus on school readiness
STUDY ON THE CHEMICAL CONSTITUENTS OF THE ESSENTIAL OIL FROM NYCTANTHES ARBOR-TRISTIS AND ITS MOLECULAR DOCKING STUDIES
Objectives: The objectives of this study were to determine the chemical composition of the essential oil obtained from the flowers of Nyctanthes arbor-tristis (NAT) and to carryout molecular docking studies against three bacterial proteins to study the mechanism of the antibacterial activity.
Methods: The essential oil was obtained from the flowers of NAT by hydrodistillation and the chemical composition was determined by gas chromatography–mass spectrometry analysis. Docking study was carried out for 14 compounds identified from NAT against three bacterial proteins 1UAG, 3TYE, and 3UDI.
Results: Fourteen compounds were identified in the essential oil. 1-octanol (74.81%) is the predominant compound followed by phytol (6.80%), bis (2-ethylhexyl) phthalate (5.88%), and eucarvone (4.23%). Many compounds are similar to that of the essential oil from jasmine. Among the 14 compounds identified, 7,9-di-tert-butyl-1-oxaspiro (4,5) deca-6,9-diene-2,8-dione interacted well with 1UAG and 3TYE and showed binding scores of −8.9 and −7.2 K Cal/mol, respectively, involving hydrophilic and hydrophobic interactions. With the protein 3UDI, the compound eucarvone exhibited a binding score of −7.1 K Cal/mol.
Conclusion: The similarities between the essential oil constituents of flowers the two plants NAT and jasmine. Therefore, it could be concluded that NAT flowers of Coimbatore are a good source of fragrance for cosmetic industry and as an antibacterial agent
COMPOSITION OF THE ESSENTIAL OIL FROM MIMOSA PUDICA LINN.
Objectives: To determine the composition of the essential oil obtained from Mimosa pudica L. (Mimosaceae) Methods: The essential oil  of M. pudica was obtained by hydro distillation using a Clevenger apparatus and the chemical composition was determined by GC-MS analysis. Results: About 23 compounds were identified from the essential oil which constitutes about 98.92 % of the oil. Among the compounds identified phthalic acid dioctyl ester (27.76 %), α-Linolenic acid (20.34 %), Cinnamaldehyde (16.24 %) are the major compounds. α-Linolenic acid is an n-3 fatty acid. Conclusion: α-Linolenic acid is one of the essential fatty acids, which is necessary for health and cannot be produced within the human body. Mimosa pudica L. (Mimosaceae) appears to be a promising herb to undergo a wide exploratio
Mode based frequency behaviour of a cracked beam
Structural analysis is mainly concerned with predicting the behaviour of a structure when subjected to any external excitation. Dynamic analysis of simple structures can be carried out using finite element analysis on various computing platforms such as MatLab. In the case of industrial applications, dynamic analysis is mainly carried out using simulations on softwares such as Ansys. The present paper compares mathematical and simulation analysis of cracked beam and the dynamic behaviour with respect to mode shape and crack position is reported
New record of pearl fish Onuxodon margaritiferae (Rendahl, 1921) from Andaman Islands
This study reports the occurrence of the pearl fish Onuxodon margaritiferae (Rendahl, 1921) for the first time from Andaman
waters, inhabiting the mantle cavity of the oyster Pteria penguin. This species is known so far from Western Australia and Philippines. The present report extends the distributional range of O. margaritiferae beyond Australian waters to Andaman waters
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Correlates of change in accelerometer-assessed total sedentary time and prolonged sedentary bouts among older English adults: results from five-year follow-up in the EPIC-Norfolk cohort.
BACKGROUND: Development of effective strategies to reduce sedentary time among older adults necessitates understanding of its determinants but longitudinal studies of this utilising objective measures are scarce. METHODS: Among 1536 older adults (≥60 years) in the EPIC-Norfolk study, sedentary time was assessed for seven days at two time-points using accelerometers. We assessed associations of change in total and prolonged bouts of sedentary time (≥ 30 minutes) with change in demographic and behavioural factors using multi-level regression. RESULTS: Over follow-up (5.3±1.9 years), greater increases in total sedentary time were associated with older age, being male, higher rate of increase in BMI, lower rate of increase in gardening (0.5 min/day/yr greater sedentary time per hour/week/yr less gardening, 95% CI 0.1, 1.0), a lower rate of increase in walking (0.2 min/day/yr greater sedentary time per hour/week/yr less walking, 95% CI 0.1, 0.3) and a higher rate of increase in television viewing. Correlates of change in prolonged sedentary bouts were similar. CONCLUSION: Individuals in specific sub-groups (older, male, higher BMI) and who differentially participate in certain behaviours (less gardening, less walking and more television viewing) but not others increase their sedentary time at a higher rate than others; utilising this information could inform successful intervention content and targeting.The EPIC-Norfolk study (DOI 10.22025/2019.10.
105.00004) has received funding from the Medical
Research Council (MR/N003284/1 and MC-UU_12015/
1) and Cancer Research UK (C864/A14136). DY was
www.aging-us.com 10 AGING
funded by a National Institute for Health Research
Doctoral Fellowship (DRF-2017-10-121). SH was
supported by the Lifelong Health and Wellbeing CrossCouncil Programme, the Medical Research Council
(MC_UU_12015/4), and Canadian Institutes of Health
Research (FRN 146766). KWi and SB were supported
by the Medical Research Council (MC_UU_12015/3)
and NJW by MC_UU_12015/1). KWe was supported
by the NIHR Cambridge Biomedical Research Centre
(IS-BRC-1215–20014). SJG and NJW are NIHR Senior
Investigators. The University of Cambridge has
received salary support in respect of SJG from the NHS
in the Eas
Assessing estrogen-induced proliferative response in an endometrial cancer cell line using a universally applicable methodological guide
Objective: Translational endometrial cancer (EC) research benefits from an in vitro experimental approach using EC cell lines. We demonstrated the steps that are required to examine estrogen induced proliferative response, a simple yet important research question pertinent to EC and devised a pragmatic methodological workflow for utilising EC cell lines in experimental models. Methods/materials: Comprehensive review of all commercially available EC cell lines was carried out, and Ishikawa cell line was selected to study the oestrogen responsiveness with HEC1A, RL95-2 and MFE280 cell lines as comparators where appropriate, examining relevant differential molecular (steroid receptors) and functional (phenotype, anchorage-independent growth, hormone responsiveness, migration, invasion and chemosensitivity) characteristics in 2D and 3D cultures in vitro using immunocytochemistry, immunofluorescence, qPCR and western blotting. In vivo tumour, formation and chemosensitivity were also assessed in a chick chorioallantoic membrane (CAM) model. Results: Short Tandem Repeat (STR) analysis authenticated the purchased cell lines while gifted cells deviated significantly from the published profile. We demonstrate the importance of prior assessment of the suitability of each cell line for the chosen in vitro experimental technique. Prior establishment of baseline, non-enriched conditions was required to induce a proliferative response to estrogen. The CAM model was a suitable in vivo multi-cellular animal model for EC, for producing rapid and reproducible data. Conclusions: We have developed a methodological guide for EC researchers when using endometrial cell lines to answer important translational research questions (exemplified by estrogen responsive cell proliferation), to facilitate robust data, while saving time and resources
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