189 research outputs found
Optimal groundwater quantity/quality planning for Salt Lake Valley
Generally, the embedding technique for optimizing groundwater management has been limited to small scale or steady-state groundwater flow management cases. The embedding approach causes sparse, highly structured constraint matrices which have been sometimes difficult to solve. Embedding applications have been limited by lack of: optimization algorithms able to easily address such matrices for large scale problems, and efficient methods for addressing common nonlinearities and converging to a solution. Computer software, USUEM, addresses these issues by: creation of alternative linear, nonlinear, combined and partitioned formulations of the same problem, implemention of an efficient cycling procedure, and good selection of optimization algorithm and computational parameters. The application of the methodology is demonstrated for a large scale study area (Salt Lake Valley) where groundwater quantity and quality management is needed and where the proportion of pumping cells is great
Optimal linear/nonlinear, quantity/quality management of complex multilayer aquifers by embedding
The embedding optimization modelling approach is adapted to aid long-term groundwater quality and quantity management of complex nonlinear multilayer aquifers. Implicit block-centered finite-difference approximations of the quasi-three-dimensional unsteady flow equation, and Galerkin finite-element approximations of the twodimensional advection-dispersion transport equation are embedded as constraints in the model. Other hydrological processes are also included as constraints. Cyclical linear differencing permits representation of nonlinear transport, even when contaminant is extracted by unsteady pumping (a decision variable). Also used are nonlinear (discontinuous derivative) constraints describing drainage, stream-aquifer interflow and evapotranspiration. The use of both linear and nonlinear formulations of the entire flow and transport model in a cyclical manner reduces execution time and improves confidence in solution optimality. The resulting model incorporates the dynamic changes in parameters characterizing nonlinear groundwater systems. The methodology is most suitable for reconnaissance planning in nonlinear systems typified by: (1) relatively large cell size, (2) large proportion of the cells having head-dependent external fluxes and pumping decision variables, and (3) the need for dispersed contaminant management. It uses a multiobjective weighting approach and goal programming to maximize sustainable groundwater extraction while achieving target groundwater concentrations in control nodes. In a second paper, the methodology is applied to the Salt Lake Valley
Glomus tumor of the leg: a case report
Glomus tumors are uncommon benign tumors developing from the neuro-myo-arterial glomus body. They are typically located in the fingers. The extra-digital involvement is unusual and makes diagnosis difficult. Only few cases have been reported in literature. We report an exceptional case of a glomus tumor of the lower leg in a 65-year-old male. The diagnosis was clinically suspected and confirmed by a biopsy. Surgical excision gave immediate pain relief. The aim of this report is to make the surgical community more aware of this entity based on the analysis of our own experience and a review of the literature
Infection of Ixodes ricinus (Acari: Ixodidae) by Borrelia burgdorferi sensu lato in North Africa
Free-living adult Ixodes ricinus L. were collected in Amdoun, situated in the Kroumiry mountains in northwestern Tunisia (North Africa). Using direct fluorescence antibody assay, the infection rate of field-collected I. ricinus by Borrelia burgdorferi sensu lato was 30.5% (n = 72). No difference in infection rate was observed between male and female ticks. Spirochetes that had been isolated from I. ricinus from Ain Drahim (Kroumiry Mountains) in 1988 were identified as Borrelia lusitaniae (formerly genospecies PotiB2). This is the first identification of a genospecies of Borrelia burgdorferi sensu lato from the continent of Afric
Manifestations tectono-diapiriques synsédimentaires et polyphasées d'âge Crétacé supérieur–Quaternaire dans la région de Zag Et Tir (Tunisie centre-nord)
Genome Sequence of Stenotrophomonas maltophilia PML168, Which Displays Baeyer-Villiger Monooxygenase Activity
Stenotrophomonas maltophilia PML168 was isolated from Wembury Beach on the English Coast from a rock pool following growth and selection on agar plates. Here we present the permanent draft genome sequence, which has allowed prediction of function for several genes encoding enzymes relevant to industrial biotechnology, including a novel flavoprotein monooxygenase
Submersed Micropatterned Structures Control Active Nematic Flow, Topology and Concentration
Coupling between flows and material properties imbues rheological matter with
its wide-ranging applicability, hence the excitement for harnessing the
rheology of active fluids for which internal structure and continuous energy
injection lead to spontaneous flows and complex, out-of-equilibrium dynamics.
We propose and demonstrate a convenient, highly tuneable method for controlling
flow, topology and composition within active films. Our approach establishes
rheological coupling via the indirect presence of fully submersed
micropatterned structures within a thin, underlying oil layer. Simulations
reveal that micropatterned structures produce effective virtual boundaries
within the superjacent active nematic film due to differences in viscous
dissipation as a function of depth. This accessible method of applying
position-dependent, effective dissipation to the active films presents a
non-intrusive pathway for engineering active microfluidic systems.Comment: 13 pages; 5 main-text-figures; 3-supplemental-figure
The correlation between middle schoolchildren allergic symptoms and airborne particle season: A cross-sectional study
Limited studies correlate allergic symptoms and associated outdoor biological particle exposure among schoolchildren globally.This study aimed to investigate the relationship between the seasonality of symptoms of allergic diseases among middle schoolchildren and the annual variation of airborne pollen and fungal spore in a hot and humid geographical region (Qatar).During November 2017 to January 2018, a self-reported study of middle schoolchildren living in the Doha capital city of Qatar was conducted, and data gathered were evaluated in relation to the collected monthly pollen and fungal spores. Participants' data were collected by conducting a survey based on a modified questionnaire adopted from the International Study of Asthma and Allergy in Childhood (ISAAC). The airborne pollen and fungal spore in Doha's atmosphere were extracted from the Doha aerobiology project (2017-2020).Among the 1000 distributed questionnaires, 100 were excluded due to significant missing data and 644 middle schoolchildren living in Doha city responded and were included in the final analysis. The symptoms of allergic rhinitis (AR) pattern among the responders with positive symptoms were strongly linked with the higher airborne fungal spore incidence during the month of November. Out of 331 students with positive symptoms, the prevalence of AR, lifetime wheeze, and eczema was 62.8%, 28.1%, and 26.6%, respectively. Asthma was significantly higher in Qatari (39.8%) compared to non-Qatari (26.7%) middle schoolchildren (P = .02).Outdoor aeroallergen may be a contributing factor in addition to other environmental and genetic predisposing factors for childhood atopic diseases in the prevalence rate of allergic symptoms among middle schoolchildren in the peninsula of Qatar
The association between airborne pollen monitoring and sensitization in the hot desert climate
Background: Pollen is a major cause of allergic respiratory diseases. In Qatar, data on the presence and prevalence of allergenic airborne types of pollen is quite limited. / Methods: The study aimed to determine and correlate the most frequently implicated airborne pollen detected by aerobiological monitoring samplers in respiratory allergy symptoms. An aerobiological survey was started on May 8, 2017. Airborne pollen was collected using two Hirst type seven-day recorder volumetric traps. Skin prick test in patients attending allergy clinics in Doha using commercial extracts was conducted. / Results: Twenty-five pollen types representing the native, as well as the introduced plants, with a relatively low daily mean concentration were observed from May 2017 to May 2019. The highest pollen concentrations were reached by Amaranthaceae (58.9%), followed by Poaceae (21.7%). SPT revealed a comparatively higher degree of sensitization to pollen. Among 940 patients, 204 were sensitized to pollen (54% female) with 135 (66.2%) and 114 (55.8%) to Amaranthaceae and Poaceae, respectively. Some patients had polysensitization. There was a statistically significant association between Amaranthaceae, and asthma (r = 0.169, P = 0.016) and allergic rhinitis (r = 0.177, P = 0.012). / Conclusions: This is the first study to monitor airborne pollen in the state of Qatar. The main pollen detected were Amaranthaceae and Poaceae. Pollen may represent a possible exacerbating factor in adult patients with allergic diseases such as asthma and allergic rhinitis
First volumetric records of airborne Cladosporium and Alternaria spores in the atmosphere of Al Khor (northern Qatar): a preliminary survey
Daily monitoring of airborne fungal spores was carried out for the first time in Al Khor city, Qatar, using a Hirst type 7-day recording volumetric spore trap, from May 2017 to May 2019. During the sampling period, the annual and monthly fluctuations, as well as intradiurnal variations of airborne fungal spore concentrations, were evaluated. Cladosporium, followed by Alternaria, were the spore types most abundant in the atmosphere of the city, with a strong interannual variability in the atmospheric concentrations being observed. The Annual Spore Integrals (ASIns) were 3334 and 1172 spore * day/m3 (2017–2018), and 6796 and 1538 spore * day/m3 (2018–2019) for Cladosporium and Alternaria, respectively. Total daily spore concentrations showed significantly positive correlations with mean, minimum, and maximum temperatures but significantly negative correlations with relative humidity. However, due to the scarce rainfalls’ days, we did not find a statistically significant correlations between Cladosporium and Alternaria spore concentrations and this parameter. Despite this, the spore peaks were strongly related to precipitations that occurred during the previous month. In general, no significant correlations were found with wind speed but, regarding wind direction, the higher percentage of spores were collected when wind blows from the 4th quadrant (NW). According to the intradiurnal pattern, Cladosporium fungal spores displayed their maximum daily concentration during 8:00–10:00 h in the morning, with a second peak in the afternoon, while for Alternaria, the maximum peaks were observed between 08:00 and 14:00 h. Because no consistent previous aerobiological studies exist from Qatar, the aim of this study is to define the seasonality and intradiurnal behaviour of these two airborne fungal spore and the role that, in such arid scene, the meteorological parameters play on the spore concentrations.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. Funding for open access charge: Universidad de Málaga / CBUA. We declare that the research reported in this manuscript received supported grant funding from the Qatar National Research Fund (QNRF)-Qatar (Project NPRP 9–241-3–043)
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