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Impacts of household sources on air pollution at village and regional scales in India
Approximately 3 billion people worldwide cook with solid fuels, such as wood, charcoal, and agricultural residues. These fuels, also used for residential heating, are often combusted in inefficient devices, producing carbonaceous emissions. Between 2.6 and 3.8 million premature deaths occur as a result of exposure to fine particulate matter from the resulting household air pollution (Health Effects Institute, 2018a; World Health Organization, 2018). Household air pollution also contributes to ambient air pollution; the magnitude of this contribution is uncertain. Here, we simulate the distribution of the two major health-damaging outdoor air pollutants (PM2:5 and O3) using state-of-thescience emissions databases and atmospheric chemical transport models to estimate the impact of household combustion on ambient air quality in India. The present study focuses on New Delhi and the SOMAARTH Demographic, Development, and Environmental Surveillance Site (DDESS) in the Palwal District of Haryana, located about 80 km south of New Delhi. The DDESS covers an approximate population of 200 000 within 52 villages. The emissions inventory used in the present study was prepared based on a national inventory in India (Sharma et al., 2015, 2016), an updated residential sector inventory prepared at the University of Illinois, updated cookstove emissions factors from Fleming et al. (2018b), and PM2:5 speciation from cooking fires from Jayarathne et al. (2018). Simulation of regional air quality was carried out using the US Environmental Protection Agency Community Multiscale Air Quality modeling system (CMAQ) in conjunction with the Weather Research and Forecasting modeling system (WRF) to simulate the meteorological inputs for CMAQ, and the global chemical transport model GEOS-Chem to generate concentrations on the boundary of the computational domain. Comparisons between observed and simulated O3 and PM2:5 levels are carried out to assess overall airborne levels and to estimate the contribution of household cooking emissions
Homozygosity for a missense mutation in the 67 kDa isoform of glutamate decarboxylase in a family with autosomal recessive spastic cerebral palsy: parallels with Stiff-Person Syndrome and other movement disorders
Background
Cerebral palsy (CP) is an heterogeneous group of neurological disorders of movement and/or posture, with an estimated incidence of 1 in 1000 live births. Non-progressive forms of symmetrical, spastic CP have been identified, which show a Mendelian autosomal recessive pattern of inheritance. We recently described the mapping of a recessive spastic CP locus to a 5 cM chromosomal region located at 2q24-31.1, in rare consanguineous families.
Methods
Here we present data that refine this locus to a 0.5 cM region, flanked by the microsatellite markers D2S2345 and D2S326. The minimal region contains the candidate gene GAD1, which encodes a glutamate decarboxylase isoform (GAD67), involved in conversion of the amino acid and excitatory neurotransmitter glutamate to the inhibitory neurotransmitter γ-aminobutyric acid (GABA).
Results
A novel amino acid mis-sense mutation in GAD67 was detected, which segregated with CP in affected individuals.
Conclusions
This result is interesting because auto-antibodies to GAD67 and the more widely studied GAD65 homologue encoded by the GAD2 gene, are described in patients with Stiff-Person Syndrome (SPS), epilepsy, cerebellar ataxia and Batten disease. Further investigation seems merited of the possibility that variation in the GAD1 sequence, potentially affecting glutamate/GABA ratios, may underlie this form of spastic CP, given the presence of anti-GAD antibodies in SPS and the recognised excitotoxicity of glutamate in various contexts
Neutrino Physics at the Turn of the Millenium
Recent solar & atmospheric nu-data strongly indicate need for physics beyond
the Standard Model. I review the ways of reconciling them in terms of 3-nu
oscillations. Though not implied by data, bi-maximal nu-mixing models emerge as
a possibility. SUSY with broken R-parity provides an attractive way to
incorporate it, opening the possibility of testing nu-anomalies at high- energy
colliders such as the LHC or at the upcoming long-baseline or nu- factory
experiments. Reconciling, in addition, the LSND hint requires a fourth, light
sterile neutrino, nus. The simplest are the most symmetric scenarios, in which
2 of the 4 neutrinos are maximally-mixed and lie at the LSND scale, while the
others are at the solar scale. The lightness of nus, the nearly maximal
atmospheric mixing, and the solar/atmospheric splittings all follow naturally
from the assumed lepton-number symmetry and its breaking. These basic schemes
can be distinguished at neutral-current-sensitive solar & atmospheric neutrino
experiments such as SNO. However underground experiments have not yet proven
neutrino masses, as there are many alternatives. For example flavour changing
interactions can play an important role in the explanation of solar and
contained atmospheric data and could be tested e.g through \mu \to e + \gamma,
\mu-e conversion in nuclei, unaccompanied by neutrino-less double beta decay.
Conversely, a short-lived numu might play a role in the explanation of the
atmospheric data. Finally, in the presence of a nus, a long-lived heavy nutau
could delay the time at which the matter and radiation contributions to the
energy density of the Universe become equal, reducing density fluctuations on
smaller scales, thus saving the standard CDM scenario, while the light nue,
numu and nus would explain the solar & atmospheric data.Comment: Invited talk at 2nd International Conference on Non-Accelerator New
Physics (NANP-99), Dubna, June 28 - July 3, 199
Different Prey Resources Suggest Little Competition Between Non-Native Frogs and Insectivorous Birds Despite Isotopic Niche Overlap
Non-native amphibians often compete with native amphibians in their introduced range, but their competitive effects on other vertebrates are less well known. The Puerto Rican coqui frog (Eleutherodactylus coqui) has colonized the island of Hawaii, and has been hypothesized to compete with insectivorous birds and bats. To address if the coqui could compete with these vertebrates, we used stable isotope analyses to compare the trophic position and isotopic niche overlap between the coqui, three insectivorous bird species, and the Hawaiian hoary bat. Coquis shared similar trophic position to Hawaii amakihi, Japanese white-eye, and red-billed leiothrix. Coquis were about 3 ‰ less enriched in δ15N than the Hawaiian hoary bat, suggesting the bats feed at a higher trophic level than coquis. Analyses of potential diet sources between coquis and each of the three bird species indicate that there was more dietary overlap between bird species than any of the birds and the coqui. Results suggest that Acari, Amphipoda, and Blattodea made up \u3e90% of coqui diet, while Araneae made up only 2% of coqui diet, but approximately 25% of amakihi and white-eye diet. The three bird species shared similar proportions of Lepidoptera larvae, which were ~25% of their diet. Results suggest that coquis share few food resources with insectivorous birds, but occupy a similar trophic position, which could indicate weak competition. However, resource competition may not be the only way coquis impact insectivorous birds, and future research should examine whether coqui invasions are associated with changes in bird abundance
Eta Carinae and the Luminous Blue Variables
We evaluate the place of Eta Carinae amongst the class of luminous blue
variables (LBVs) and show that the LBV phenomenon is not restricted to
extremely luminous objects like Eta Car, but extends luminosities as low as
log(L/Lsun) = 5.4 - corresponding to initial masses ~25 Msun, and final masses
as low as ~10-15 Msun. We present a census of S Doradus variability, and
discuss basic LBV properties, their mass-loss behaviour, and whether at maximum
light they form pseudo-photospheres. We argue that those objects that exhibit
giant Eta Car-type eruptions are most likely related to the more common type of
S Doradus variability. Alternative atmospheric models as well as
sub-photospheric models for the instability are presented, but the true nature
of the LBV phenomenon remains as yet elusive. We end with a discussion on the
evolutionary status of LBVs - highlighting recent indications that some LBVs
may be in a direct pre-supernova state, in contradiction to the standard
paradigm for massive star evolution.Comment: 27 pages, 6 figures, Review Chapter in "Eta Carinae and the supernova
imposters" (eds R. Humphreys and K. Davidson) new version submitted to
Springe
Mortality, Recruitment and Change of Desert Tree Populations in a Hyper-Arid Environment
BACKGROUND: Long-term vegetation changes in hyper-arid areas have long been neglected. Mortality, recruitment and change in populations of the ecologically and culturally important and drought persistent Acacia tortilis and Balanites aegyptiaca are therefore estimated in the Eastern Desert of Egypt, and are related to the primary agents of change, water conditions and human intervention. METHODOLOGY: A change analysis using high-resolution Corona images (1965) in combination with field data (2003) is the basis for recruitment, mortality and change estimates. For assessing the influence of water conditions on patterns in recruitment and survival, different types of generalized linear models are tested. CONCLUSIONS: The overall trend in population size in that part of the Eastern Desert studied here is negative. At some sites this negative trend is alarming, because the reduction in mature trees is substantial (>50%) at the same time as recruitment is nearly absent. At a few sites there is a positive trend and better recruitment. Frequent observations of sprouting in saplings indicate that this is an important mechanism to increase their persistence. It is the establishment itself that seems to be the main challenge in the recruitment process. There are indications that hydrological variables and surface water in particular can explain some of the observed pattern in mortality, but our results indicate that direct human intervention, i.e., charcoal production, is the main cause of tree mortality in the Eastern Desert
Returning to work after stroke: perspectives of employer stakeholders, a qualitative study.
Purpose: More than 40 % of working age adults with stroke fail to return to work. The work context is a key factor in return to work, but little is known about the experiences of employers in supporting employees with stroke. The aim of this study was to explore return to work after stroke from the employer perspective, to identify key features associated with success and to seek participants’ views regarding the role of healthcare in return to work. Methods: Data was gathered through 18 semi-structured interviews with employer stakeholders and included small business owners, line managers, human resources and occupational health staff. Data was analysed thematically. Results: The main themes identified were: the impact of stroke on the employer, characteristics of the employee, communication, knowledge and information, experience of other stakeholders, integrating healthcare in return to work. Conclusion: Employers face complex emotional and practical issues when helping an employee return to work after stroke, for which many lack knowledge and experience. The range and quality of support networks that they access is variable and advice and support from clinicians is welcomed. Further research is necessary to investigate how such support could be funded and integrated within existing service provision
Genetic polymorphisms of MDM2 and TP53 genes are associated with risk of nasopharyngeal carcinoma in a Chinese population
<p>Abstract</p> <p>Background</p> <p>The tumor suppressor TP53 and its negative regulator MDM2 play crucial roles in carcinogenesis. Previous case-control studies also revealed <it>TP53 </it>72Arg>Pro and <it>MDM2 </it>309T>G polymorphisms contribute to the risk of common cancers. However, the relationship between these two functional polymorphisms and nasopharyngeal carcinoma (NPC) susceptibility has not been explored.</p> <p>Methods</p> <p>In this study, we performed a case-control study between 522 NPC patients and 722 healthy controls in a Chinese population by using PCR-RFLP.</p> <p>Results</p> <p>We found an increased NPC risk associated with the <it>MDM2 </it>GG (odds ratio [OR] = 2.83, 95% confidence interval [CI] = 2.08-3.96) and TG (OR = 1.49, 95% CI = 1.16-2.06) genotypes. An increased risk was also associated with the <it>TP53 </it>Pro/Pro genotype (OR = 2.22, 95% CI = 1.58-3.10) compared to the Arg/Arg genotype. The gene-gene interaction of <it>MDM2 </it>and <it>TP53 </it>polymorphisms increased adult NPC risk in a more than multiplicative manner (OR for the presence of both <it>MDM2 </it>GG and <it>TP53 </it>Pro/Pro genotypes = 7.75, 95% CI = 3.53-17.58).</p> <p>Conclusion</p> <p>The findings suggest that polymorphisms of <it>MDM2 </it>and <it>TP53 </it>genes may be genetic modifier for developing NPC.</p
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