5,786 research outputs found
Impacts of the 20th January 2005 solar proton event on the ozone concentration of Indian cities
The ozone data obtained from Nimbus-7 and Earth probe Total Ozone Mapping Spectrometer (TOMS) has been used to study the
impact of coronal mass ejection (CME) on the columnar ozone concentration in India. A comparison of columnar ozone values for different solar
proton events (SPE) observed at Srinagar indicates that although the 20th Jan., 2005 SPE was the most intense in the last 15 years, the ozone depletion
was found to be maximum in the 23rd March, 1991 event followed by 20th Jan., 2005, 4th Nov., 2001, 19th Oct., 1989 and 28th Oct., 2003 events. A
comparison between the ozone levels observed in different Indian cities for a few days after the 20th Jan., 2005 SPE indicates that the ozone values were
found to decrease sharply at higher latitudes compared to places located in the tropics .The ozone values measured by TOMS, Dobson Spectrometer
and AURA Ozone Monitoring Instrument (OMI) were found to decrease for a short period from 20th January to 25th January after which the ozone
levels started recovering to normal values. The vertical ozone profiles obtained from Microwave Limb Sounder for New Delhi, indicate that the ozonemixing
ratio in the 3.0 to 10.0 hPa pressure range decreased consistently from 21st Jan., 2005 to 25th Jan., 2005 and thereafter, recovered by the 31st
January, 2005.Impacts of the 20th January 2005 solar proton event on the ozone
concentration of Indian cities
Nandita D Ganguly 1* and K N Iyer 2
1 Department of Physics, St.Xavier’s College, Ahmedabad-380 009, Gujarat, India
2 Department of Physics, Saurashtra University, Rajkot-360 005, Gujarat, India
E–mail: [email protected]
Received 1 December 2005, accepted 27 February 20061 Department of Physics, St.Xavier’s College, Ahmedabad-380 009, Gujarat, India
2 Department of Physics, Saurashtra University, Rajkot-360 005, Gujarat, Indi
Learning Engagement of Adult Females in Remote Physical Fitness Program Through Mobile App Intervention
The use of digital devices such as laptops, personal digital assistants, and mobile phones as learning tools has gained prominence in formal education, generating increased research interest in potential growth areas. According to Jeong and So (2020), there seems to be inadequate empirical evidence from extensive research to support its learning effectiveness in the fitness domain, especially among women who have been underrepresented in economically stressed areas. One of the several explanations for this disparity is the failure to consider women’s intersecting cultural identities or potential for social impact. This paper focuses on addressing this issue by conducting a qualitative study. It involves a focus group comprising 15 adult females aged 24 and above. The primary objective is to assess how virtual learning influences the learning perception of adult female learners at a yoga and fitness studio. Interactive self-paced mobile-assisted learning modules were facilitated through the use of mobile phones. An open-ended questionnaire was designed using online resources for primary data collection. The findings were derived by cross-referencing data collected from recordings, interviews, and questionnaires. The study revealed that participating in online fitness classes could enhance women's involvement in fitness-related activities
Learning Engagement of Adult Females in Remote Physical Fitness Program Through Mobile App Intervention
The use of digital devices such as laptops, personal digital assistants, and mobile phones as learning tools has gained prominence in formal education, generating increased research interest in potential growth areas. According to Jeong and So (2020), there seems to be inadequate empirical evidence from extensive research to support its learning effectiveness in the fitness domain, especially among women who have been underrepresented in economically stressed areas. One of the several explanations for this disparity is the failure to consider women’s intersecting cultural identities or potential for social impact. This paper focuses on addressing this issue by conducting a qualitative study. It involves a focus group comprising 15 adult females aged 24 and above. The primary objective is to assess how virtual learning influences the learning perception of adult female learners at a yoga and fitness studio. Interactive self-paced mobile-assisted learning modules were facilitated through the use of mobile phones. An open-ended questionnaire was designed using online resources for primary data collection. The findings were derived by cross-referencing data collected from recordings, interviews, and questionnaires. The study revealed that participating in online fitness classes could enhance women's involvement in fitness-related activities
Emergence of a non-scaling degree distribution in bipartite networks: a numerical and analytical study
We study the growth of bipartite networks in which the number of nodes in one
of the partitions is kept fixed while the other partition is allowed to grow.
We study random and preferential attachment as well as combination of both. We
derive the exact analytical expression for the degree-distribution of all these
different types of attachments while assuming that edges are incorporated
sequentially, i.e., a single edge is added to the growing network in a time
step. We also provide an approximate expression for the case when more than one
edge are added in a time step. We show that depending on the relative weight
between random and preferential attachment, the degree-distribution of this
type of network falls into one of four possible regimes which range from a
binomial distribution for pure random attachment to an u-shaped distribution
for dominant preferential attachment
Magnetoresistance of metallic perovskite oxide LaNiO
We report a study of the magnetoresistance (MR) of the metallic perovskite
oxide LaNiO as a function of the oxygen stoichiometry
( 0.14), magnetic field (H ) and temperature (1.5K T 25K). We find a strong dependence of the nature of MR on the oxygen
stoichiometry. The MR at low temperatures change from positive to negative as
the sample becomes more oxygen deficient (i.e, increases). Some of the
samples which are more resistive, show a resistivity minima at
20K. We find that in these samples the MR is positive at T >
and negative for T < . We conclude that in the absence of
strong magnetic interaction, the negative MR in these oxides can arise from
weak localisation effects.Comment: 10 pages in REVTeX format, 4 eps fig
Immunological defect in leprosy patients: altered T-lymphocyte signals
The early events of activation were studied in paucibacillary (TT/BT) and multibacillary (BL/LL) leprosy patients by stimulation of their lymphocytes with mitogenic agents (calcium ionophore A23187/PMA) and Micobacterium leprae antigen (PGL-1). Maximum proliferation in response to PMA/A23187 and PGL-1 was observed in the BT/TT patients and the control group, respectively. Inositol triphosphate (IP3) and calcium were constitutively elevated in BT/TT and LL/BL patients. PMA/A23187 caused an increase in both IP3 and [Ca2+]i in BT/TT patients and controls. PGL-1 marginally increased IP3 levels in BT/TT patients. In the LL/BL patients, although PMA/A23187 increased IP3 levels, but no change was seen in [Ca2+]i, PGL-1 had no effect. Protein kinase C levels were seen to be associated with particulate fractions in BT/TT patients and were found to increase further in response to PMA/A23187. PGL-1 did not increase translocation of protein kinase C in controls or LL/BL patients. A preactivated and sensitised state of T-lymphocytes was observed in BT/TT patients, responsive to antigen and mitogens, whereas the cells of LL/BL patients were unresponsive to PGL-1. The altered signal transduction events characterised in the MB patients thus correlate well with the anergic state of their cells
Scheduling Virtual Conferences Fairly: {A}chieving Equitable Participant and Speaker Satisfaction
Recently, almost all conferences have moved to virtual mode due to the
pandemic-induced restrictions on travel and social gathering. Contrary to
in-person conferences, virtual conferences face the challenge of efficiently
scheduling talks, accounting for the availability of participants from
different timezones and their interests in attending different talks. A natural
objective for conference organizers is to maximize efficiency, e.g., total
expected audience participation across all talks. However, we show that
optimizing for efficiency alone can result in an unfair virtual conference
schedule, where individual utilities for participants and speakers can be
highly unequal. To address this, we formally define fairness notions for
participants and speakers, and derive suitable objectives to account for them.
As the efficiency and fairness objectives can be in conflict with each other,
we propose a joint optimization framework that allows conference organizers to
design schedules that balance (i.e., allow trade-offs) among efficiency,
participant fairness and speaker fairness objectives. While the optimization
problem can be solved using integer programming to schedule smaller
conferences, we provide two scalable techniques to cater to bigger conferences.
Extensive evaluations over multiple real-world datasets show the efficacy and
flexibility of our proposed approaches.Comment: In proceedings of the Thirty-first Web Conference (WWW-2022). arXiv
admin note: text overlap with arXiv:2010.1462
{FairRec}: {T}wo-Sided Fairness for Personalized Recommendations in Two-Sided Platforms
We investigate the problem of fair recommendation in the context of two-sided
online platforms, comprising customers on one side and producers on the other.
Traditionally, recommendation services in these platforms have focused on
maximizing customer satisfaction by tailoring the results according to the
personalized preferences of individual customers. However, our investigation
reveals that such customer-centric design may lead to unfair distribution of
exposure among the producers, which may adversely impact their well-being. On
the other hand, a producer-centric design might become unfair to the customers.
Thus, we consider fairness issues that span both customers and producers. Our
approach involves a novel mapping of the fair recommendation problem to a
constrained version of the problem of fairly allocating indivisible goods. Our
proposed FairRec algorithm guarantees at least Maximin Share (MMS) of exposure
for most of the producers and Envy-Free up to One item (EF1) fairness for every
customer. Extensive evaluations over multiple real-world datasets show the
effectiveness of FairRec in ensuring two-sided fairness while incurring a
marginal loss in the overall recommendation quality.Comment: In Proceedings of The Web Conference (WWW) 202
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