Prefabricated inpatient wards have been proven to be an efficient alternative to quickly extend the caring capacity for patients. In this study, three typical ventilation strategies were studied ...using computational fluid dynamics in a prefabricated Coronavirus disease 2019 double-patient ward. Pollutants are the respiratory droplets and aerosols injected from two manikins. They are modelled as particles with different diameters (3 μm, 6 μm, 12 μm, 20 μm, 45 μm and 175 μm) by the Eulerian–Lagrangian model. Three ventilation strategies with an identical air change rate of 12.3 h−1 but different layouts of inlets and outlets are implemented. The flow field, flow structures and particle trajectories have been analysed and compared among the three ventilation strategies. The fate of particles is analysed and compared quantitatively. It is found that small particles (<20 μm) can move along with the main flow streams. Most of them are removed by ventilation to the outlet(s). Large particles (>45 μm) cannot move with the flow streams over a long path. Most of them deposit on solid surfaces in different regions of the ward in each ventilation strategy. Health workers should pay close attention to these polluted areas. Targeted cleaning of the polluted areas is necessary in a prefabricated inpatient ward. To promote the removal of some large particles (e.g., 45 μm) by the outlet(s), the outlet(s) should be installed inside the landing area of large particles and close to the polluted source(s).
•Comparative study of three ventilation strategies in prefabricated COVID-19 ward.•Simulated flow fields agree well with benchmark experiment.•Respiratory droplets and aerosols from the coughing process have been simulated.•The fate of particles is analysed and compared quantitatively.
Ship routing and scheduling in the new millennium Christiansen, Marielle; Fagerholt, Kjetil; Nygreen, Bjørn ...
European journal of operational research,
08/2013, Letnik:
228, Številka:
3
Journal Article
Recenzirano
► Comprehensive review of refereed papers published during the last decade. ► The number of papers, as well as outlets, about doubles every decade. ► Problems of wider scope, and more specialized ...ones, have been addressed. ► Liner shipping, marine inventory routing and optimal speed have come to the forefront. ► Complex critical problems remain wide open and provide challenging opportunities.
We review research on ship routing and scheduling and related problems during the new millennium and provide four basic models in this domain. The volume of research in this area about doubles every decade as does the number of research outlets. We have found over a hundred new refereed papers on this topic during the last decade. Problems of wider scope have been addressed as well as more specialized ones. However, complex critical problems remain wide open and provide challenging opportunities for future research.
In 2016, Tosei General Hospital, a tertiary emergency medical facility with 633 beds in Japan, experienced a large nosocomial outbreak of carbapenemase-producing Enterobacterales (CPE) that had ...spread to numerous sink outlets. Based on our experience with using steam cleaners to suppress CPE on environmental surfaces, we report the efficacy of steam cleaners in the disinfection of sink outlets. Steam cleaners were used to disinfect 22 target areas. CPE disappeared in 90.9% of the sink outlets within the first two months after disinfection, and, after 12 months, 54.5% of the sink outlets remained negative throughout the remainder of the study period. This study demonstrates the effectiveness of using steam cleaners to disinfect sink outlets contaminated with CPE.
An updated zoning policy eliminating all alcohol outlets (liquor stores) in residential districts was implemented to reduce high rates of violent crime in Baltimore City. Diverse stakeholders were ...engaged in group model building (GMB) activities to develop causal loop diagrams (CLDs) that elucidate the impact of the new zoning policy on crime, and more broadly, the potentially unintended social and environmental consequences of the policy. Three distinct groups, community advocates, city officials/academics, and community residents, participated in three separate GMB sessions. Three CLDs, one from each stakeholder group, were created to depict the possible outcomes of the zoning policy. Our findings offer insight into potential unintended consequences of removing liquor stores from residential areas that may undermine the policy. Community members described the need for additional supports related to mental health and substance use, opportunities for investment in the community, access to other goods and services, and community‐police relations to ensure the policy achieved its intended goal of reducing violent crime. Our findings highlight the importance of timely engagement of local stakeholders to understand how complex neighborhood dynamics and contextual factors could impact the effectiveness of a zoning policy change.
Highlights
The complex interplay between neighborhood context and the alcohol environment is poorly understood.
Using systems thinking, diverse stakeholders developed causal loop diagrams.
Baltimore City alcohol zoning policy was linked to diverse social and environmental consequences.
Removing alcohol outlets may result in unintended consequences, including an increase in crime.
In our previous study, a novel flow field design for a polymer electrolyte fuel cell (PEFC) called “Hybrid Serpentine-Interdigitated (HSI)” had been proposed. Although it was very promising in terms ...of performance and pressure drop, it still had a major drawback of the low oxygen concentration area. To improve its design and performance, three HSI configurations with different numbers of gas inlet and outlet, namely one inlet and one outlet HSI (1-IO HSI), one inlet and two outlets HSI (1I-2O HSI) and two inlets and two outlets HSI (2-IO HSI) were numerically investigated and compared with the conventional single channel serpentine (1S). The investigation on the cell performance and other transport behaviors has been carried out using CFD techniques via ANSYS FLUENT software. At a practical operating potential of about 0.6 V of 50 cm2 PEFCs, the 2-IO HSI offered the best distributions of oxygen, current density and water due to the shorter channel length. More importantly, the 2-IO HSI could contribute to a reduction in cathode pressure drop by 90%, as compared with the 1S, resulting in the enhancement in the net power output by 6%, approximately.
•A novel hybrid serpentine-interdigitated (HSI) flow field is proposed.•In a 50 cm2 PEFC, the 2-IO HSI flow field outperformed the 1S.•The 2-IO HSI provided the best uniform distributions of oxygen, current and water.•The cathode pressure drop of the 2-IO HSI was reduced by 90% vis-à-vis the 1S.•The 2-IO HSI enhanced net power out by 6%, compared with the 1S.
In this paper the modification of a vortex tube is shown. The feature of this vortex tube is that it has an additional air inlet in the hot outlet area along the tube axis designed to redistribute ...air consumption between cold and hot outlets. Computational experiments are done in openFOAM toolbox using sonicFoam solver. In order to increase computational speed the mesh is being decomposed into equal parts, which allows for the parallel run using MPI on a single computer. The results of the experiment show temperature values and air consumption on the corresponding outlets in relation to the change of the vortex tube length. A conclusion about the effective vortex tube length is made.
Objective
To assess the quality of antibiotics sampled from authorised sales outlets (ATs) (i.e. hospitals/health centres, pharmacies and licensed chemical shops) and unauthorised sales outlets ...(UATs) (mainly street vendors) in Ghana and to explore the health‐seeking behaviour of medicine consumers.
Methods
The contents of 14 active pharmaceutical ingredients (APIs) in 348 sampled products were determined using a validated liquid chromatography–tandem mass spectrometry (LC‐MS/MS) method. Data on health‐seeking practices were collected through entry and exit interviews and field observations from ATs and UATs.
Results
It was observed that 66.38% of all sampled antibiotic products were substandard; they either contained less (<90%) or more API (>110%) than the label claim. Medicines from UATs recorded substantially less API contents than those from ATs (F(2,419) = 43.01, P < 0.0001). For example, 90.54% of street vendor samples contained < 90% of the APIs. 75.93% of consumers often sought self‐treatment with drugs without a prescription from UATs, as they perceived UATs as easily accessible, trustworthy and knowledgeable, and their medicines as inexpensive. These consumers rather thought of the formal healthcare providers as alternative sources.
Conclusions
Consumers who purchase from UATs are at high risk of receiving substandard medicines. The quality of medicines in the national healthcare system, in the supply chain and in the distribution system needs to be monitored regularly to reduce the incidence of substandard medicines and their impact on antimicrobial resistance. The fight against substandard medicines needs to incorporate a full understanding of socioeconomic factors that drive consumer decisions regarding their health and choice of healthcare providers.
Objectif
Evaluer la qualité des antibiotiques prélevés auprès des vendeurs autorisés (VA) (c'est‐à‐dire les hôpitaux/centres de santé, les pharmacies et les magasins de produits chimiques agréés) et des vendeurs non autorisés (VNA) (principalement les vendeurs de rue) au Ghana et étudier le comportement des utilisateurs de médicaments en quête de santé.
Méthodes
Le contenu de 14 principes actifs (PA) pharmaceutiques dans 348 produits échantillonnés a été déterminé à l'aide d'une méthode validée de chromatographie liquide et de spectrométrie de masse en tandem (LC‐MS/MS). Les données sur les pratiques de recherche de santé ont été collectées par le biais d'entretiens d'entrée et de sortie, et d'observations sur le terrain des VA et des VNA.
Résultats
Il a été observé que 66,38% de tous les produits antibiotiques échantillonnés étaient inférieurs aux normes; ils contenaient soit moins (<90%), soit plus de PA (>110%) que ce qui était indiqué sur la notice. Les médicaments provenant des VNA ont enregistré une quantité de PA sensiblement inférieure à celle des VA (F(2,419) = 43.01, P < 0,0001). Par exemple, 90,54% des échantillons de vendeurs de rue contenaient <90% de PA. 75,93% des utilisateurs ont souvent cherché à se soigner eux‐mêmes avec des médicaments sans ordonnance des VNA, car ils ont perçu les VNA comme étant facilement accessibles, fiables et bien informés, et leurs médicaments comme étant peu coûteux. Ces utilisateurs considéraient également les prestataires de soins de santé officiels comme des sources alternatives.
Conclusions
Les utilisateurs qui s'approvisionnent auprès des VNA courent un risque élevé de recevoir des médicaments de qualité inférieure. La qualité des médicaments dans le système national de santé, dans la chaîne d'approvisionnement et dans le système de distribution doit être contrôlée régulièrement pour réduire l'incidence des médicaments de qualité inférieure et leur impact sur la résistance aux antimicrobiens. La lutte contre les médicaments de qualité inférieure doit intégrer une compréhension complète des facteurs socioéconomiques qui déterminent les décisions des utilisateurs concernant leur santé et le choix des prestataires de soins de santé.
The Three Gorges Project (TGP) is a world known project to utilize and manage the water resources of the
Yangtze River. The reservoir stores water at the end of the flood season, and replenishes ...downstream
reaches with water in dry seasons. In addition to such benefits, the TGP has irreversibly changed the
hydrological process and the river-lake relation of the middle and lower reaches. In this paper, a
hydrodynamic model was established to quantify the impact of the TGP's operation on the water
exchange between Dongting Lake and the Yangtze River during 2009–2013. The results indicated that:
the operation of the TGP has considerably reduced the peak discharge and the flood volume of the main
stream and the Dongting Lake area. The inflow volume from the Yangtze River to Dongting Lake via three
outlets decreased by 1.9–3.5 billion m3/yr, while the outflow volume from Dongting Lake to the Yangtze
River at Chenglingji increased by 0.3–1.6 billion m3 in September and 0.4–0.6 billion m3 in October,
respectively. This research provides valuable information for flood control, irrigation, and water allocation
in the middle and lower reaches of the Yangtze River, and serves as a typical case for investigating
the impact of other hydropower projects around the world.
& 2017 International Research and Training Centre on Erosion and Sedimentation/the World Association
for Sedimentation and Erosion Research. Published by Elsevier B.V. All rights reserved.
TP-River Wang, Lei; Yao, Tandong; Chai, Chenhao ...
Bulletin of the American Meteorological Society,
05/2021, Letnik:
102, Številka:
5
Journal Article
Recenzirano
Odprti dostop
Monitoring changes in river runoff at the Third Pole (TP) is important because rivers in this region support millions of inhabitants in Asia and are very sensitive to climate change. Under the ...influence of climate change and intensified cryospheric melt, river runoff has changed markedly at the TP, with significant effects on the spatial and temporal water resource distribution that threaten water supply and food security for people living downstream. Despite some in situ observations and discharge estimates from state-of-the-art remote sensing technology, the total river runoff (TRR) for the TP has never been reliably quantified, and its response to climate change remains unclear. As part of the Chinese Academy of Sciences’ “Pan-Third Pole Environment Study for a Green Silk Road,” the TP-River project aims to construct a comprehensive runoff observation network at mountain outlets (where rivers leave the mountains and enter the plains) for 13 major rivers in the TP region, thereby enabling TRR to be accurately quantified. The project also integrates discharge estimates from remote sensing and cryosphere–hydrology modeling to investigate long-term changes in TRR and the relationship between the TRR variations and westerly/monsoon. Based on recent efforts, the project provides the first estimate (656 ± 23 billion m³) of annual TRR for the 13 TP rivers in 2018. The annual river runoff at the mountain outlets varies widely between the different TP rivers, ranging from 2 to 176 billion m³, with higher values mainly corresponding to rivers in the Indian monsoon domain, rather than in the westerly domain.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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