170 research outputs found
Construction, Instrumentation, and Preliminary Verification of a Physical Hydrologic Model
From theoretical consideration involving a rationalized dimensional analysis of the rainfall-runoff phenomena, dimensionless products of the pertinent variables are derived. These dimensionless products guided the design and construction of a rainstorm simulator and topographic model. The design and construction of these two basic elements of the physical hydrologic model are described. A description of the instrumentation and several relevant calibration tests is followed by a discussion of two preliminary verification test sets. The tests indicated that some necessary refinements in equipment and instrumentation were needed before more precise experimental data could be obtained. Further, the tests produced results which encouraged further investigation and would guide the design of further experimental tests
Evaluating air quality by combining stationary, smart mobile pollution monitoring and data-driven modelling
© 2019 Elsevier Ltd Air pollution impact assessment is a major objective for various community councils in large cities, which have lately redirected their attention towards using more low-cost sensing units supported by citizen involvement. However, there is a lack of research studies investigating real-time mobile air-quality measurement through smart sensing units and even more of any data-driven modelling techniques that could be deployed to predict air quality accurately from the generated data-sets. This paper addresses these challenges by: a) proposing a comparative and detailed investigation of various air quality monitoring devices (both fixed and mobile), tested through field measurements and citizen sensing in an eco-neighbourhood from Lorraine, France, and by b) proposing a machine learning approach to evaluate the accuracy and potential of such mobile generated data for air quality prediction. The air quality evaluation consists of three experimenting protocols: a) first, we installed fixed passive tubes for monitoring the nitrogen dioxide concentrations placed in strategic locations highly affected by traffic circulation in an eco-neighbourhood, b) second, we monitored the nitrogen dioxide registered by citizens using smart and mobile pollution units carried at breathing level; results revealed that mobile-captured concentrations were 3â5 times higher than the ones registered by passive-static monitoring tubes and c) third, we compared different mobile pollution stations working simultaneously, which revealed noticeable differences in terms of result variability and sensitivity. Finally, we applied a machine learning modelling by using decision trees and neural networks on the mobile-generated data and show that humidity and noise are the most important factors influencing the prediction of nitrogen dioxide concentrations of mobile stations
Recommended from our members
Identification of Chromatin-Associated Regulators of MSL Complex Targeting in Drosophila Dosage Compensation
Sex chromosome dosage compensation in Drosophila provides a model for understanding how chromatin organization can modulate coordinate gene regulation. Male Drosophila increase the transcript levels of genes on the single male X approximately two-fold to equal the gene expression in females, which have two X-chromosomes. Dosage compensation is mediated by the Male-Specific Lethal (MSL) histone acetyltransferase complex. Five core components of the MSL complex were identified by genetic screens for genes that are specifically required for male viability and are dispensable for females. However, because dosage compensation must interface with the general transcriptional machinery, it is likely that identifying additional regulators that are not strictly male-specific will be key to understanding the process at a mechanistic level. Such regulators would not have been recovered from previous male-specific lethal screening strategies. Therefore, we have performed a cell culture-based, genome-wide RNAi screen to search for factors required for MSL targeting or function. Here we focus on the discovery of proteins that function to promote MSL complex recruitment to âchromatin entry sites,â which are proposed to be the initial sites of MSL targeting. We find that components of the NSL (Non-specific lethal) complex, and a previously unstudied zinc-finger protein, facilitate MSL targeting and display a striking enrichment at MSL entry sites. Identification of these factors provides new insight into how MSL complex establishes the specialized hyperactive chromatin required for dosage compensation in Drosophila
Lessons Learned from Implementing a Community Health Worker-initiated Referral Strengthening Intervention in Haiti: A Mixed-Methods Program Case Study
Referral processes linking communities to facilities are under-appreciated and lack evaluation, particularly in humanitarian settings. Community health workers or agents de santĂ© communautaire polyvalent (ASCPs) in Haiti refer communities to health facilities for a range of services. This program case study assessed implementation of a public-private referral strengthening intervention within on-going community health programming, including a triplicate referral form, supportive training, and follow-up structures. We applied mixed methods to describe referral trends using routine programmatic data, factors affecting implementation and referral completion through a pre-intervention referred patient survey (n = 525), meeting observations, and interviews with ASCPs, supervisors, and key stakeholders (n = 88). We found that the intervention demonstrates little influence on referral trends, but qualitatively enhances the referral process for ASCPs and supervisory stakeholders in Haiti. It improves supervision relationships and shows promise for enhanced community-integrated patient monitoring systems â when supported by financial support and non-governmental and governmental partners, but is vulnerable to sociopolitical, geographic, and insecurity challenges preventing referral completion. Integrating intervention activities within existing programming and scaling the triplicate referral form in Haiti can strengthen the national ASCP curricula. Globally, we suggest adapting the triplicate referral form as a promising job-aid and data-reporting tool within community health worker programs
Limited oxidative stress favors resistance to skeletal muscle atrophy in hibernating brown bears (Ursus Arctos)
publishedVersio
New Outlook on the Possible Existence of Superheavy Elements in Nature
A consistent interpretation is given to some previously unexplained phenomena
seen in nature in terms of the recently discovered long-lived high spin super-
and hyper-deformed isomeric states. The Po halos seen in mica are interpreted
as due to the existence of such isomeric states in corresponding Po or nearby
nuclei which eventually decay by gamma- or beta-decay to the ground states of
210Po, 214Po and 218Po nuclei. The low-energy 4.5 MeV alpha-particle group
observed in several minerals is interpreted as due to a very enhanced alpha
transition from the third minimum of the potential-energy surface in a
superheavy nucleus with atomic number Z=108 (Hs) and atomic mass number around
271 to the corresponding minimum in the daughter.Comment: 8 pages, 8 figures, 5 tables. Paper presented at VII Int.
School-Seminar on Heavy Ion Physics, May 27 - June 1, 2002, Dubna, Russi
The effect of obesity on spirometry tests among healthy non-smoking adults
<p>Abstract</p> <p>Introduction</p> <p>The effects of obesity on pulmonary functions have not been addressed previously among Saudi population. We aim to study the effects of obesity on spirometry tests among healthy non-smoking adults.</p> <p>Methods</p> <p>A cross sectional study conducted among volunteers healthy non-smoking adults Subjects. We divided the subjects into two groups according to their BMI. The first group consisted of non-obese subjects with BMI of 18 to 24.9 kg/m2 and the second group consisted of obese subjects with BMI of 30 kg/m2 and above. Subjects underwent spirometry tests according to American thoracic society standards with measurement of the following values: the forced vital capacity (FVC), forced expiratory volume in one second (FEV1), peak expiratory flow rate (PEF) and forced mid-expiratory flow (FEF25-75).</p> <p>Results</p> <p>The total subjects were 294 with a mean age of 32 years. There were 178 males and 116 females subjects. We found no significant differences in FEV1 (p value = 0.686), FVC (p value = 0.733), FEV1/FVC Ratio (p value = 0.197) and FEF25-75 (p value = 0.693) between the obese and non-obese subjects. However, there was significantly difference in PEF between the two groups (p value < 0.020).</p> <p>Conclusion</p> <p>Obesity does not have effect on the spirometry tests (except PEF) among health non-smoking adults. We recommend searching for alternative diagnosis in case of findings abnormal spirometry tests results among obese subjects.</p
Computer-Assisted Prototyping of Advanced Microsystems
Contains reports on five research projects.Defense Advanced Research Projects Agency Contract DABT 63-95-C-0088Stanford Universit
Lipidomics Reveals Seasonal Shifts in a Large-Bodied Hibernator, the Brown Bear
Prior to winter, heterotherms retain polyunsaturated fatty acids (âPUFAâ), resulting in enhanced energy savings during hibernation, through deeper and longer torpor bouts. Hibernating bears exhibit a less dramatic reduction (2â5°C) in body temperature, but lower their metabolism to a degree close to that of small hibernators. We determined the lipid composition, via lipidomics, in skeletal muscle and white adipose tissues (âWATâ), to assess lipid retention, and in blood plasma, to reflect lipid trafficking, of winter hibernating and summer active wild Scandinavian brown bears (Ursus arctos). We found that the proportion of monounsaturated fatty acids in muscle of bears was significantly higher during winter. During hibernation, omega-3 PUFAs were retained in WAT and short-length fatty acids were released into the plasma. The analysis of individual lipid moieties indicated significant changes of specific fatty acids, which are in line with the observed seasonal shift in the major lipid categories and can be involved in specific regulations of metabolisms. These results strongly suggest that the shift in lipid composition is well conserved among hibernators, independent of body mass and of the animalsâ body temperature
- âŠ