Flux scaling and plume structure in high Ra - high Sc turbulent convection

The arrangement of brine above water across a micro porous permeable membrane is used to study high Rayleigh Number($10^{11}- 10^{10}$) high Schmidt number(650)turbulent convection. The flux shows 4/3$^{rd}$ scaling with line plume as the near wall coherent structures. Shifting of multiple large scale flow cells result in changing near membrane mean shear directions for large aspect ratios. Lower aspect ratios show single large scale flow cell and constant sense of mean shear.Comment: 7 pages, 7 Figures, Published in Proceedings of the Tenth Asian Congress of Fluid Mechanics 17--21, May 2004, Peradeniya, Srilank

The influence of CSR and ethical self-identity in consumer evaluation of cobrands

An important aspect of brand perception emanates from its corporate social responsibility (CSR) activity. When two brands involved in CSR activities form a cobranding alliance, their respective CSR perceptions can impact consumer attitudes toward the alliance. As an ethically-oriented strategy, the alliance can be potentially beneficial to both partner brands, and can create opportunities for promoting CSR activities. The research streams on brand management, cobranding, and CSR, however, are silent about this important branding strategy that has several embedded business and societal benefits. This study examines how CSR-based consumer perceptions and ethical self-identity impact consumer evaluation of cobrands. Employing a quasi-experimental between-subjects design, the study tests six cobranding scenarios in three product categories. The data were collected via structured questionnaires resulting in 318 valid responses. The data were analyzed employing Partial Least Squares Structural Equation Modeling. The results confirm that positive CSR perceptions toward the partner brands are robust indicators of attitudes toward cobrands. Further, the match between the CSR activities of the partner brands (positive CSR fit) and the product categories (product fit) influences cobrand attitudes. The results also show evidence of ‘spill-over’ effects, where the alliance has a positive impact on subsequent CSR perceptions toward the partner brands. Additionally, the findings demonstrate an asymmetry in the effects of the cobrand on subsequent CSR perceptions wherein consumers with low ethical self-identity show greater spill-over effects from the cobrand than those with high ethical self-identity. The study contributes to knowledge in the domains of business ethics, cobranding, and social responsibility. The findings have managerial implications for designing CSR-based ethical branding strategies for cobrands

Impaired perception of biological motion in Parkinson’s disease

OBJECTIVE: We examined biological motion perception in Parkinson’s disease (PD). Biological motion perception is related to one’s own motor function and depends on the integrity of brain areas affected in PD, including posterior superior temporal sulcus. If deficits in biological motion perception exist, they may be specific to perceiving natural/fast walking patterns that individuals with PD can no longer perform, and may correlate with disease-related motor dysfunction. METHOD: Twenty-six nondemented individuals with PD and 24 control participants viewed videos of point-light walkers and scrambled versions that served as foils, and indicated whether each video depicted a human walking. Point-light walkers varied by gait type (natural, parkinsonian) and speed (0.5, 1.0, 1.5 m/s). Participants also completed control tasks (object motion, coherent motion perception), a contrast sensitivity assessment, and a walking assessment. RESULTS: The PD group demonstrated significantly less sensitivity to biological motion than the control group (p < .001, Cohen’s d = 1.22), regardless of stimulus gait type or speed, with a less substantial deficit in object motion perception (p = .02, Cohen’s d = .68). There was no group difference in coherent motion perception. Although individuals with PD had slower walking speed and shorter stride length than control participants, gait parameters did not correlate with biological motion perception. Contrast sensitivity and coherent motion perception also did not correlate with biological motion perception. CONCLUSION: PD leads to a deficit in perceiving biological motion, which is independent of gait dysfunction and low-level vision changes, and may therefore arise from difficulty perceptually integrating form and motion cues in posterior superior temporal sulcus.Published versio

Multifractal nature of plume structure in high Rayleigh number convection

The geometrically different plan forms of near wall plume structure in turbulent natural convection, visualised by driving the convection using concentration differences across a membrane, are shown to have a common multifractal spectrum of singularities for Rayleigh numbers in the range $10^{10}- 10^{11}$ at Schmidt number of 602. The scaling is seen for a length scale range of $2^5$ and is independent of the Rayleigh number, the flux, the strength and nature of the large scale flow, and the aspect ratio. Similar scaling is observed for the plume structures obtained in the presence of a weak flow across the membrane. This common non trivial spatial scaling is proposed to be due to the same underlying generating process of the near wall plume structures.Comment: 11pages, 16 figures Accepted in Journal of Fluid mechanics. Revised version. Added two more figures and related discussion on suggestion of referee

Biological motion perception in Parkinson's disease

Parkinson’s disease (PD) disrupts many aspects of visual perception, which has negative functional consequences. How PD affects perception of moving human bodies, or biological motion, is unknown. The ability to accurately perceive others’ motion is related to one’s own motor ability and depends on the integrity of brain areas affected in PD, including superior temporal sulcus and premotor cortex. Biological motion perception may therefore be compromised in PD but also provide a target for intervention, with perceptual training potentially improving motor function. Experiment 1 investigated whether perception of biological motion was impaired in PD (N=26) relative to neurologically-healthy control (NC; N=24) individuals. Participants viewed videos of point-light human figures and judged whether or not they depicted walking. As predicted, PD were less sensitive to biological motion than NC. This deficit was not associated with participants’ own walking difficulties or with other perceptual deficits (contrast sensitivity, coherent motion perception). Experiment 2 evaluated the hypothesis that PD deficits would extend to more socially-complex biological motion. PD (N=23) and NC (N=24) viewed point-light figures depicting communicative and non-communicative (object-oriented) gestures. The PD group was less accurate than NC in describing non-communicative gestures, an effect driven by PD men, who also had difficulty perceiving communicative gestures. Experiment 3 tested the efficacy of perceptual training for PD. Because biological motion perception is associated with motor function, it was hypothesized that perceptual training would improve walking. Individuals with PD were randomized to Gait Observation (N=13; viewing videos of healthy and unhealthy gait) or Landscape Observation (N=10; viewing videos of moving water) and trained daily for one week while gait data were collected with accelerometers. Post-training, only the Gait Observation group self-reported increased mobility, though improvements were not seen in objective gait data (daily activity, walking speed, stride length, stride frequency, leg swing time, gait asymmetry). These studies demonstrate that individuals with PD have difficulty perceiving biological motion (walking and socially-complex gestures). Improving biological motion perception led to enhancement in self-perceived walking ability. Perceptual training that incorporates more explicit learning over a longer time period may be required to effect objective improvements in walking.2018-12-06T00:00:00

Assessment of clinical profile of acute viral hepatitis among paediatric age group patients at tertiary care centre

Background:Viral hepatitis keeps on being a significant medical issue worldwide and India. This issue is brought about by the 5 pathogenic hepatotropic infections perceived to date: hepatitis A (HAV), E(HEV), C(HCV), B(HBV) and D(HDV) infections. Be that as it may, most successive viral operators of acute viral hepatitis with significant wellbeing trouble in India are hepatitis A infection and hepatitis E infections. Material &amp; Methods:The present prospective study was conducted at department of pediatrics of our tertiary care hospital. The study was anobservational study conducted during a period of one year. A total of 100 children who were of age 1 to 16 years and who were diagnosed withtwo or more symptoms of loss of appetite, nausea, vomiting, pain abdomen, itching and jaundice enrolled for study. along with patients who had positive serum levels of IgM HAV, IgM HEV and IgM HCV and hepatitis B surface antigen [HBsAg] were enrolled for study. Results: In present study, out of total study participants, based on the signs and symptoms, the most common presenting symptom was jaundice present in92% patientswhich was followed by hepatomegaly present in83% patients,which was followed by dark urinepresent in 82% patientswhich was followed by loss of appetite present in 82% patients. Out of total study participants, nausea was present among 76% patientswhich was followed by vomiting present in73% patients,which was followed by feverpresent in 70% patientswhich was followed by pain abdomen present in 82% patients. Out of total study participants, loose stools was present among 54% patientswhich was followed by itching present in38% patients,which was followed by Splenomegaly present in 21% patientswhich was followed by ascites present in 14% patients.Conclusion:It's critical to make mindfulness in the general public with respect to preventive measures including accessibility of immunization particularly in rustic territory. Better sterilization, arrangement of clean drinking water appropriate sewage removal, and government funded instruction are the backbones for counteraction of HAV and HEV contamination. Key words:Clinical profile, Viral hepatitis, hepatitis

Integral analysis of laminar indirect free convection boundary layers with weak blowing for Schmidt no. ~ 1

Laminar natural convection at unity Schmidt number over a horizontal surface with a weak normal velocity at the wall is studied using an integral analysis. To characterise the strength of the blowing, we define a non-dimensional parameter called the blowing parameter. After benchmarking with the no blowing case, the effect of the blowing parameter on boundary layer thickness, velocity and concentration profiles is obtained. Weak blowing is seen to increase the wall shear stress. For blowing parameters greater than unity, the diffusional flux at the wall becomes negligible and the flux is almost entirely due to the blowing.Comment: 10 pages, published in International Communications in heat and mass transfer,Vol31,No8, 2004, pp 1199 -120

Normal discrimination of spatial frequency and contrast across visual hemifields in left-onset Parkinson’s disease: evidence against perceptual hemifield biases

Individuals with Parkinson's disease (PD) with symptom onset on the left side of the body (LPD) show a mild type of left-sided visuospatial neglect, whereas those with right-onset (RPD) generally do not. The functional mechanisms underlying these observations are unknown. Two hypotheses are that the representation of left-space in LPD is either compressed or reduced in salience. We tested these hypotheses psychophysically. Participants were 31 non-demented adults with PD (15 LPD, 16 RPD) and 17 normal control adults (NC). The spatial compression hypothesis was tested by showing two sinusoidal gratings, side by side. One grating's spatial frequency (SF) was varied across trials, following a staircase procedure, whereas the comparison grating was held at a constant SF. While fixating on a central target, participants estimated the point at which they perceived the two gratings to be equal in SF. The reduced salience hypothesis was tested in a similar way, but by manipulating the contrast of the test grating rather than its SF. There were no significant differences between groups in the degree of bias across hemifields for SF discrimination or for contrast discrimination. Results did not support either the spatial compression hypothesis or the reduced salience hypothesis. Instead, they suggest that at this perceptual level, LPD do not have a systematically biased way of representing space in the left hemifield that differs from healthy individuals, nor do they perceive stimuli on the left as less salient than stimuli on the right. Neglect-like syndrome in LPD instead presumably arises from dysfunction of higher-order attention.Published versio

The effect of Parkinson’s disease subgroups on verbal and nonverbal fluency

BACKGROUND: Parkinson’s disease (PD) leads to deficits in executive function, including verbal and nonverbal fluency, as a result of compromised frontostriatal circuits. It is unknown whether deficits in verbal and nonverbal fluency in PD are driven by certain subgroups of patients, or how strategy use may facilitate performance. PARTICIPANTS: Sixty-five nondemented individuals with PD, including 36 with right-body onset (RPD; 20 with tremor as their initial symptom, 16 nontremor) and 29 with left-body onset (LPD; 14 with tremor as their initial symptom, 15 nontremor), and 52 normal control participants (NC) took part in the study. MEASUREMENTS: Verbal fluency was assessed using the FAS and Animals tests. Nonverbal fluency was assessed using the Ruff Figural Fluency Test. RESULTS: Both RPD and LPD were impaired in generating words and in using clustering and switching strategies on phonemic verbal fluency, whereas different patterns of impairment were found on nonverbal fluency depending on the interaction of side of onset and initial motor symptom (tremor vs. nontremor). Strategy use correlated with number of correct responses on verbal fluency in LPD, RPD, and NC. By contrast, on nonverbal fluency, strategy use correlated with correct responses for RPD and LPD, but not for NC. CONCLUSION: Our findings demonstrate the importance of considering subgroups in PD and analyzing subcomponents of verbal and nonverbal fluency (correct responses, errors, and strategies), which may depend differently on the integrity of dorsolateral prefrontal cortex, inferior frontal cortex, and anterior cingulate cortex.Published versio

Study of microchannels fabricated using desktop fused deposition modeling systems

Microfluidic devices are used to transfer small quantities of liquid through micro-scale channels. Conventionally, these devices are fabricated using techniques such as soft-lithography, paper microfluidics, micromachining, injection moulding, etc. The advancement in modern additive manufacturing methods is making three dimensional printing (3DP) a promising platform for the fabrication of microfluidic devices. Particularly, the availability of low-cost desktop 3D printers can produce inexpensive microfluidic devices in fast turnaround times. In this paper, we explore fused deposition modelling (FDM) to print non-transparent and closed internal micro features of in-plane microchannels (i.e., linear, curved and spiral channel profiles) and varying cross-section microchannels in the build direction (i.e., helical microchannel). The study provides a comparison of the minimum possible diameter size, the maximum possible fluid flow-rate without leakage, and absorption through the straight, curved, spiral and helical microchannels along with the printing accuracy of the FDM process for two low-cost desktop printers. Moreover, we highlight the geometry dependent printing issues of microchannels, pressure developed in the microchannels for complex geometry and establish that the profiles in which flowrate generates 4000 Pa are susceptible to leakages when no pre or post processing in the FDM printed parts is employed.fals