Mechanical characterization of animal fibre-based composites

293-297Horsehair-based composites have been prepared by reinforcing polylactic acid (PLA) using hot compression molding. The weight fraction of horsehair fibre in composites has been varied from 0% to 30 wt.% to investigate the effect of fibre loading on the mechanical properties and moisture absorption performance of the developed composites. The mechanical properties, such as strength and modulus (tensile and flexural), impact energy, and moisture absorption behaviour of the fabricated composites, are experimentally evaluated. The experimental results recommend that the composites reinforced with 20 wt.% horsehair exhibit superior mechanical properties as compared to other developed composites. The tensile strength and modulus, flexural strength and modulus, Charpy and Izod impact energy of the composites reinforced with 20 wt.% horsehair are improved by 9.52, 28.74, 7, 5.63, 398.11 and 379.31% as compared to, one-on-one, neat PLA. The findings also reveal that the percentage of moisture absorption of the developed composites increases with an increase in the fibre content in the developed composites

Mechanical characterization of animal fibre-based composites

Horsehair-based composites have been prepared by reinforcing polylactic acid (PLA) using hot compression molding. The weight fraction of horsehair fibre in composites has been varied from 0% to 30 wt.% to investigate the effect of fibre loading on the mechanical properties and moisture absorption performance of the developed composites. The mechanical properties, such as strength and modulus (tensile and flexural), impact energy, and moisture absorption behaviour of the fabricated composites, are experimentally evaluated. The experimental results recommend that the composites reinforced with 20 wt.% horsehair exhibit superior mechanical properties as compared to other developed composites. The tensile strength and modulus, flexural strength and modulus, Charpy and Izod impact energy of the composites reinforced with 20 wt.% horsehair are improved by 9.52, 28.74, 7, 5.63, 398.11 and 379.31% as compared to, one-on-one, neat PLA. The findings also reveal that the percentage of moisture absorption of the developed composites increases with an increase in the fibre content in the developed composites.

Attitude of Doctors Towards Homosexuality at a Medical College, West Bengal, India: A Cross-sectional Study

Introduction: Attitude towards homosexuality varies differently in different parts of the world. But, almost everywhere social stigma and marginalisation make them vulnerable to poor health and social outcomes. So, physicians should be made aware and sensitive about this issue in order to provide optimal care without any prejudices and discrimination. Aim: To assess the attitude of the doctors towards the homosexuality at a Medical College, West Bengal, India. Materials and Methods: A cross-sectional study was conducted for three months from August 2021 and October 2021 at Raiganj Government Medical College and Hospital, West Bengal, India. A predesigned, pretested, structured questionnaire was distributed to each of the faculty members of this medical college. The questionnaire was kept anonymous for name, religion, department or academic qualification and began with asking questions on age and sex. It consisted of 18 statements, nine substatements of relevant attitude along with additional specific comments on the subject. The faculty members were requested to put the filled up questionnaires in a drop box placed at a designated area in the Department of Psychiatry. In this way responses were finally obtained from 56 out of total 69 faculty members. All of them were postgraduate degree holders. The attitude scores were compared on the basis of age and sex using Kruskal-Wallis and Mann-Whitney U tests. A p-value was calculated to find the association of attitude score with age and gender groups. Results: Among the study participants 21 (37.5%) were in ≥50 years age group, 18 (32.1%) in 40-49 years age group and 17 (30.4%) in ≤40 years age group. Males were 41 (73.2%) and females were 15 (26.8%). Forty six (82.2%) participants agreed that homosexuality is “constitutionally determined” (an inherent fundamental right as per Indian constitution). However 34 (60.7%) did not believe it to be a “sexual orientation”. Half of the participants are of the opinion that “homosexuals are easily recognizable”. Forty three (76.8%) respondents are of the opinion that “homosexuals should not be employed in school”. Also 41 (73.2%) believed that “homosexuals are danger to children”. Only 23 (41.1%) generally agreed that they “did not feel embarrassed while talking about homosexuality”. Just above half of the participants agreed that they “really did not understand homosexuality. The attitude scores did not however vary according to age (p-value=0.25) or sex (p-value=0.09) groups. Conclusion: Majority of the study participants had inadequate knowledge on the issues of homosexuality with a more or less neutral stance in their attitude

महिषासुर: मिथक व परंपराएं

इक्कसवीं सदी के दूसरे दशक में भारत में महिषासुर आंदोलन द्विज संस्कृति के लिए चुनौती बनकर उभरा। इसके माध्यम से आदिवासियों, पिछड़ों और दलितों के एक बड़े हिस्से ने अपनी सांस्कृतिक दावेदारी पेश की। लेकिन यह आंदोलन क्या है, इसकी जड़ें समाज में कहां तक फैली हैं, बहुजनों की सांस्कृतिक परंपरा में इसका क्या स्थान है, मौजूदा लोक-जीवन में महिषासुर की उपस्थिति किन-किन रूपों में है, इसके पुरातात्विक साक्ष्य क्या हैं? गीतों-कविताओं व नाटकों में महिषासुर किस रूप में याद किए जा रहे हैं और अकादमिक-बौद्धिक वर्ग को इस आंदोलन ने किस रूप में प्रभावित किया है, उनकी प्रतिक्रियाएं क्या हैं? आदि प्रश्नों पर विमर्श हमें एक ऐसी बौद्धिक यात्रा की ओर ले जाने में सक्षम हैं, जिससे हममें अधिकांश अभी तक अपरिचित रहे हैं। क्या महिषासुर दक्षिण एशिया के अनार्यों के पूर्वज थे, जो बाद में एक मिथकीय चरित्र बन कर बहुजन संस्कृति के प्रतीक पुरुष बन गए? क्या यह बहुत बाद की परिघटना है, जब माकण्डेय पुराण, दुर्गासप्तशती जैसे ग्रंथ रच कर, एक कपोल-कल्पित देवी के हाथों महिषासुर की हत्या की कहानी गढ़ी गई? इस आंदोलन की सैद्धांतिकी क्या है? प्रमोद रंजन द्वारा संपादित किताब “महिषासुर: मिथक व परंपराएं” में लेखकों ने उपरोक्त प्रश्नों पर विचार किया है तथा विलुप्ति के कगार पर खड़े असुर समुदाय का विस्तृत नृवंशशास्त्रीय अध्ययन भी प्रस्तुत किया है। इस पुस्तक में समकालीन भारतीय साहित्य में महिषासुर पर लिखी गई कविताओं व गीतों का प्रतिनिधि संकलन भी है तथा महिषासुर की बहुजन कथा पर आधारित एक नाटक भी प्रकाशित है। समाज-विज्ञान व सांस्कृतिक विमर्श के अध्येताओं, सामाजिक-राजनीतिक कार्यकर्ताओं, साहित्य प्रेमियों के लिए यह एक आवश्यक पुस्तक है

The Neural Correlates of Mirror Therapy – An EEG Study

Mirror therapy is a non-invasive treatment procedure in which visual observation of a mirror-reflected moving limb ameliorates some sensorimotor symptoms associated with an impaired (or amputated) limb. Initially proposed as a possible treatment method for persistent phantom pain in limb amputees, over the years the therapy has also been applied in cases of limb paralysis or weakness due to stroke, complex regional pain syndrome, other neuropathic pain syndromes and sensorimotor malfunction. However, the precise mechanisms underlying its efficacy as a treatment are unknown, as are its neural underpinnings. This thesis studied the neural correlates of mirror therapy. Specifically, it investigated whether the perception of hand movement through a mirror evokes activation in the primary motor cortex (M1) contralateral to the non-moving hand (the M1 ipsilateral to the moving hand). The primary hypothesis was the mirror visual feedback (MVF) of the hand movements in the mirror view conditions would increase ipsilateral M1 activation compared to the ipsilateral M1 activation evoked by the actual hand in the direct view conditions (where ipsilateral is defined with respect to the moving hand). Directly related to the main hypothesis, this study also investigated the influence of visual feedback (or observation of self-movement) on M1 activation. A series of experiments were conducted using a unimanual hand movement and manipulations on visual observation. Electroencephalography (EEG) was used to record brain activity in healthy individuals and in people with upper limb amputation while they performed unimanual extension-flexion hand movement in different experimental conditions. The lateralized readiness potential (LRP) was measured in controls, and the steady-state movement related cortical potential (ssMRCP) was used as an alternative measure in amputees (given that LRP cannot be calculated); these were measured from continuous EEG as a marker of M1 activation associated with each experimental condition. In Experiment 1, both the direct and mirror view of hand movements produced LRPs in healthy individuals, with the mirror view conditions revealing clear activation in M1 contralateral to the non-moving hand (ipsilateral to the moving hand). The ipsilateral activation was significantly higher in mirror conditions than the ipsilateral activation in direct conditions. Consistent with Experiment 1, Experiment 2, which was conducted with people with right upper limb amputation, showed higher ssMRCP amplitude in mirror view conditions compared to direct view conditions at the hemisphere ipsilateral to the actual (volitional) movement (contralateral to the reflected image of movement appearing as the hand on the amputated side). Ipsilateral activation in the mirror view condition was consistently higher than ipsilateral activation associated with the direct view condition at frontal (F3), central (C3) and parietal (P3) electrode sites. Experiment 3 revealed that visual observation of hand movements affects M1 excitability in healthy individuals. It showed that visual perception of own hand movements facilitates M1 activation whereas the performance of same hand movement with closed eyes inhibits M1 activation. In summary, the present study provides clear evidence of M1 activation in association with a non-moving hand (which is visually perceived as moving). This unambiguous demonstration of M1 activation in association with the visually-perceived (non-moving) hand, suggests that perception of hand movement can directly lead to M1 activation. This thesis proposed a direct visual-to-motor activation mechanism to explain how visual feedback, particularly MVF, modulates sensorimotor activity. The direct visual-to-motor activation mechanism suggests that perception of hand movement reduces the activity of inhibitory networks in M1 that in turn facilitates M1 activation

The Neural Correlates of Mirror Therapy – An EEG Study

Mirror therapy is a non-invasive treatment procedure in which visual observation of a mirror-reflected moving limb ameliorates some sensorimotor symptoms associated with an impaired (or amputated) limb. Initially proposed as a possible treatment method for persistent phantom pain in limb amputees, over the years the therapy has also been applied in cases of limb paralysis or weakness due to stroke, complex regional pain syndrome, other neuropathic pain syndromes and sensorimotor malfunction. However, the precise mechanisms underlying its efficacy as a treatment are unknown, as are its neural underpinnings. This thesis studied the neural correlates of mirror therapy. Specifically, it investigated whether the perception of hand movement through a mirror evokes activation in the primary motor cortex (M1) contralateral to the non-moving hand (the M1 ipsilateral to the moving hand). The primary hypothesis was the mirror visual feedback (MVF) of the hand movements in the mirror view conditions would increase ipsilateral M1 activation compared to the ipsilateral M1 activation evoked by the actual hand in the direct view conditions (where ipsilateral is defined with respect to the moving hand). Directly related to the main hypothesis, this study also investigated the influence of visual feedback (or observation of self-movement) on M1 activation. A series of experiments were conducted using a unimanual hand movement and manipulations on visual observation. Electroencephalography (EEG) was used to record brain activity in healthy individuals and in people with upper limb amputation while they performed unimanual extension-flexion hand movement in different experimental conditions. The lateralized readiness potential (LRP) was measured in controls, and the steady-state movement related cortical potential (ssMRCP) was used as an alternative measure in amputees (given that LRP cannot be calculated); these were measured from continuous EEG as a marker of M1 activation associated with each experimental condition. In Experiment 1, both the direct and mirror view of hand movements produced LRPs in healthy individuals, with the mirror view conditions revealing clear activation in M1 contralateral to the non-moving hand (ipsilateral to the moving hand). The ipsilateral activation was significantly higher in mirror conditions than the ipsilateral activation in direct conditions. Consistent with Experiment 1, Experiment 2, which was conducted with people with right upper limb amputation, showed higher ssMRCP amplitude in mirror view conditions compared to direct view conditions at the hemisphere ipsilateral to the actual (volitional) movement (contralateral to the reflected image of movement appearing as the hand on the amputated side). Ipsilateral activation in the mirror view condition was consistently higher than ipsilateral activation associated with the direct view condition at frontal (F3), central (C3) and parietal (P3) electrode sites. Experiment 3 revealed that visual observation of hand movements affects M1 excitability in healthy individuals. It showed that visual perception of own hand movements facilitates M1 activation whereas the performance of same hand movement with closed eyes inhibits M1 activation. In summary, the present study provides clear evidence of M1 activation in association with a non-moving hand (which is visually perceived as moving). This unambiguous demonstration of M1 activation in association with the visually-perceived (non-moving) hand, suggests that perception of hand movement can directly lead to M1 activation. This thesis proposed a direct visual-to-motor activation mechanism to explain how visual feedback, particularly MVF, modulates sensorimotor activity. The direct visual-to-motor activation mechanism suggests that perception of hand movement reduces the activity of inhibitory networks in M1 that in turn facilitates M1 activation

Processing of task-irrelevant sounds during typical everyday activities in children

Our ability to focus on a task and ignore task-irrelevant stimuli is critical for efficient cognitive functioning. Attention control is especially required in the auditory modality as sound has privileged access to perception and consciousness. Despite this important function, little is known about auditory attention during typical everyday activities in childhood. We investigated the impact of task-irrelevant sounds on attention during three everyday activities - playing a game, reading a book, watching a movie. During these activities, environmental novel sounds were presented within a sequence of standard sounds to 7-8-year-old children and adults. We measured ERPs reflecting early sound processing and attentional orienting and theta power evoked by standard and novel sounds during these activities. Playing a game versus reading or watching reduced early encoding of sounds in children and affected ongoing information processing and attention allocation in both groups. In adults, theta power was reduced during playing at mid-central brain areas. Results show a pattern of immature neuronal mechanisms underlying perception and attention of task-irrelevant sounds in 7-8-year-old children. While the type of activity affected the processing of irrelevant sounds in both groups, early stimulus encoding processes were more sensitive to the type of activities in children

Optimal design of PD-Fuzzy-PID cascaded controller for automatic generation control

In this research paper a novel cascaded PD-Fuzzy-PID controller is recommended for a conventional hybrid-source unified power system for automatic generation control. The optimization of scaling parameters of the suggested PD-Fuzzy-PID controller is done by hybrid Grey Wolf Optimization-Teaching Learning Based Optimization (GWO-TLBO) technique. A sudden disturbance of 0.01 p.u. is considered in area 1 and ITAE is taken as the evaluative function in the recommended optimization process. The proposed work considers three different sources of generating systems namely, a hydro, a gas and a reheat thermal unit. Both AC tie-line and AC-DC tie-line is considered in analyzing the dynamic performances of the system. The robustness and sensitiveness of the proposed controller are further put to test for random load variations and nominal parameter variations. Analysis of the dynamic characteristics of the system is executed considering a number of time response specifications like settling time, peak overshoots and undershoots. During the analysis the optimum specifications obtained by the recommended technique are compared with some pre-published results in order to prove the supremacy of this novel controller over existing controllers. Further, the frequency stability of the system is improved by employing an UPFC in the system

Accessibility and availability of reproductive health care services at primary health centre level and association with health outcome in Aspirational Districts of India

Background: This study concerns the reproductive health care of women of reproductive age in the selected Aspirational districts in India. This paper mainly aims to identify the level of accessibility and availability of reproductive health care and their interlinking with the health outcomes in terms of institutional delivery and percentage of women who received any Antenatal Check-up. Study design: This is a cross sectional study. Methods: A composite index has been constructed at the district level for every indicator (accessibility, availability, and health outcome) to identify the level of accessibility and availability and to analyse the association between accessibility, availability, and health outcomes using the Pearson chi-square test and ternary diagram. The thematic maps used for showing the disparities of indicators in the selected Aspirational districts. Results: After developing the composite index for accessibility and availability of health care, it is shown that the districts which ranked in accessibility, not ranked in availability of health care. The study reveals that the overall composite index for ranking the districts in terms of accessibility and availability, closely associated with the health outcomes. Accessibility and availability are also associated with the health outcome of reproductive health in Aspirational districts in India. Accessibility of health care services is more significant for better health outcomes than the availability of health care services in the Aspirational districts in India. Conclusion: Accessibility and availability are the component for access to health care and influence the health outcome