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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
511

Treatment outcomes in perinatally-infected HIV positive adolescents and young adults after 10+ years on antiretroviral therapy

Anderson, Kim 30 January 2019 (has links)
There are currently more than 30 0 000 children under the age of 15 living with HIV in South Africa (SA). Due to a combination of recent success in preventing new vertical infections and success of paediatric antiretroviral treatment (ART) programmes in improving life-expectancy in perinatally HIV-infected (PHIV) children, the burden of paediatric HIV in SA has changed to older children. An increasing population of PHIV children on ART is reaching adolescence, yet information on long-term treatment outcomes in this group is lacking. There is very limited published data on treatment outcomes in PHIV children after ≥10 years on ART in high income countries (HIC), and none in low- and middle-income countries (LMIC). We conducted a retrospective cohort study of PHIV adolescents on ART for ≥ 10 years at a single ART facility. The main objective of the study was to describe long-term clinical, growth, immunologic and virologic outcomes in the cohort. Part A, the protocol, as submitted for departmental and ethical approval, details the purpose and methodology of the study. Part B, the literature review, discusses what is known about long-term treatment outcomes in PHIV children on ART to date. It compares findings between HIC and LMIC. Long-term growth, immunologic and virologic outcomes, as well as factors associated with viral failure are described. The paucity of long-term data is demonstrated, indicating the need for further research on the topic. Part C, the journal-ready manuscript, details the methodology, results and interpretation of the longitudinal analysis of long-term treatment outcomes among 127 PHIV-infected adolescents and young adults on ART for ≥10 years. After median follow-up of 12 years since ART initiation, 80% of the cohort were virally suppressed and 79% had optimal immunologic status (CD4 >500 cells/μl). These results are favourable overall, but >40% of adolescents were on 2nd-line ART with poorer immunologic outcomes than those on 1st-line ART, and approximately one in three children experienced viral failure during adolescence. This highlights the vulnerability of this group, which requires careful further management. Appendices include all supporting documentation necessary for the above parts of the mini-dissertation.
512

Spring Hollow Reservoir: Application of a two-dimensional water quality model

Dorsel, Daniel S. 09 July 1998 (has links)
The BETTER water quality model, created by TVA, was used to model the temperature and dissolved oxygen (DO) in Spring Hollow Reservoir. The water balance consisted of pump discharge from the Roanoke River, runoff, releases at the dam, leakage, and storage. The geometry of the reservoir was represented by four columns and a variable number of five-foot layers. Through a sensitivity analysis, the parameters that influenced temperature and DO the most were determined. Temperature was then calibrated to a subset of the 19-month simulation period by systematically varying the most sensitive parameters. DO was calibrated to the entire simulation period due to the young age of the reservoir and the inconsistent inflow rates and timing. The verification process showed that the model reasonably reproduced the seasonal temperature patterns. By varying the sediment oxygen demand temporally and spatially, the model depicted the gradual hypolimnetic oxygen depletion in the reservoir. The model results suggest that the inflow organics and subsequent settling and accumulation are key factors in the DO depletion rate. Therefore, to enhance water quality conditions in the reservoir, a monitoring system in the Roanoke River should be installed with filling carried out when water quality in the river is optimal. For future modeling purposes, this research indicated that the model was very sensitivity to meteorological data, especially in determining temperature. Thus, a weather station located at the reservoir would permit collection of more accurate meteorological data, leading to greater confidence in the interpretation of the model predictions. / Master of Science
513

Rening av kontaminerat vatten med hjälp av biomassa : En alternativ reningsmetod för metallkontaminerat vatten i Uganda / Rening av kontaminerat vatten med hjälp av biomassa : En alternativ reningsmetod för metallkontaminerat vatten i Uganda

Hermelin, Samuel, Suokko, Joel January 2016 (has links)
För att en hållbar utveckling ska kunna nås enligt de 17 miljömålen från Paris krävs en enkel och billig metod för vattenrening. Denna rapport behandlar en relativt oprövad metod som innebär att man ska rena metallförorenat vatten med hjälp av adsorptionsytor hos biomassa. Syftet med rapporten är att ta reda på ifall koppar- och koboltjoner skulle kunna bindas till vassväxten Cyperus papyrus och bomullsväxten Imperata cylindrica. Hur konkurrensen mellan kopparn och kobolten påverkar adsorptionen till biomassan samt vilken av biomassorna som lämpar sig bäst för rening skall också fastställas. Området som granskades var den koppar- och koboltförorenade floden River Nyamwamba i Uganda vilket gjorde att metallerna koppar och kobolt studerades. Biomassorna Cyperus papyrus och Imperata cylindrica växer i stor utsträckning i Uganda så dessa valdes ur ett hållbarhetsperspektiv då eventuella transporter kan minimeras. Adsorptionsförmågan av metallerna bestämdes genom en laboration där biomassorna kunde adsorbera mellan 45,55 - 69,84 % av kobolten och 63,74 -77,54 % av kopparn hos de fyra olika lösningarna som testades. Imperata cylindrica visade sig ha en något bättre adsorptionsförmåga. Möjliga metoder som skulle kunna implementeras i samhället kan vara filter tillverkade av biomassa men det krävs fortfarande mer forskning inom området innan dessa kan tas i bruk.
514

Avloppsrening med mikrobiella bränsleceller : En litteraturstudie om den senaste forskningens framsteg / Microbial fuel cells for wastewater treatment : A review of recent progress in research

Lindvall, Sara January 2016 (has links)
Rening av avloppsvatten är en viktig samhällsfunktion med höga krav på reningskapacitet och effektivitet, men traditionella reningsme- toder kräver mycket energi. Med anledning av detta har avloppsrening med mikrobiella bränsleceller (MFC) blivit ett stort forskningsområde. En MFC använder sig av nedbrytande mikroorganismer i en elektroke- misk redoxreaktion och kan därför användas för rening av avloppsvatten samtidigt som elektrisk energi kan utvinnas. I den här litteraturstudien sammanfattas den senaste forskningen kring hur de hinder som åter- står för storskalig avloppsrening med MFC kan överbryggas. Hindren är både ekonomiska och driftstekniska och tyngdpunkten i denna studie ligger på kostnadseffektivitet och ekologisk hållbarhet samt vilken roll det är rimligt att MFC kan anta i framtidens avloppsreningssystem. Det analyserade forskningsmaterialet antyder att den mest kostnadseffektiva grundkonfigurationen av MFC för avloppsrening är membranlös och fri från kostsamma katalysatorer. Att utnyttja biologiska sätt att underlätta redoxreaktionen, såsom att använda sig av bioanod, biokatod och luftka- tod, är både ekonomiskt och ekologiskt hållbart jämfört med traditionell MFC-teknik. Vidare har forskning kring användning av naturmaterial samt kol-, metalloxid- eller polymerbaserade nanomaterial visat på lo- vande resultat, men mycket arbete återstår innan MFC-tekniken till ful- lo är både driftsäker och kostnadseffektiv. Sammantaget visar resultaten att MFC-forskningen kring ekonomiskt och ekologiskt hållbara material och konfigurationer gjort vissa framsteg de senaste åren, samt att dessa bör utnyttjas i sammanhang där MFC integreras med beprövad renings- teknik, såsom membranbioreaktorer eller konstgjorda våtmarker, för att öka möjligheterna till att finna ett ekonomiskt och ekologiskt hållbart avloppsreningssystem. / Wastewater treatment is a crucial function in the urban society. With increasing population the need for energy efficient and ecologically sus- tainable solutions for water recovery will grow. Microbial Fuel Cells (MFC) are a promising technique with a potential to contribute to solv- ing this task, which is why they have been under extensive studies for several years in the context of wastewater treatment and energy recov- ery. A MFC designed for wastewater treatment consists of an electrolysis cell that uses wastewater as electrolyte, turning the chemical energy into electrical energy whilst microbes digests the nutrients and organic sub- stances. Some specific microbes, electrochemically active bacterias, are capable of anaerobic digestion and when the organic loadings are con- sumed, electrons and protons are released and a current can be collected from the fuel cell. This paper is a review of the most recent research focused on solving the critical problems that still prohibit a large scale usage of MFC for wastewater treatment. The most prominent issues are related to high initial costs och operational stability and the aim of this study is to summarize the state of art regarding cost effective materials and configurations and also to discuss what the future role of MFC in wastewater treatment might be. Due to the limited format only the eco- nomical and ecological aspects of sustainability is regarded. The results from this review indicates that the most cost effective basic configuration of MFC is membranless and free from expensive catalysts. Many studies show that the use of biological catalysts, such as microbial biofilm on the electrode surfaces, is a low-cost and effective way of stimulating the oxidation-reduction-reactions that drives the MFC. Also the use of air- cathodes, where the cathode is exposed to the air in order to stimulate oxygen reduction, instead of energy consuming air pump, is a promising way forward. Recently the use of natural materials, such as loofah and clay ware, have been studied with various results, and if the operational stability and overall performance could be enhanced this might well be a sustainable rout in research. Another strong trend is the use of cole-, metaloxide- or polymerbased nanomaterials which have a documented ability to increase both electric and purifying efficiencies, but the ecolog- ical sustainability regarding nanomaterials is a complex question which is not answered in this paper. Altogether, the research covered in this work shows that large scale wastewater treatment with MFC alone not at all is near at hand. However, some minor improvements have been made regarding cost effective and ecologically sustainable materials and con- figurations for MFC, and these findings could well be used in a context where MFC is integrated with other techniques, such as a Membrane Bio Reactor or Constructed Wetland, in order to take advantage of the syner- gistic effects that has been noticed in several studies. This might be the most reasonable role for MFC to play in the future wastewater treatment business, thereby contributing to the global strive for sustainability.
515

Recidivism Rates of Sexual Offenders up to 7 Years Later Does Treatment Matter?

Zgoba, Kristen M., Simon, Leonore M.J. 01 September 2005 (has links)
This article critically reviews the evidence on sex offender treatment and subsequently provides new estimates on short-term recidivism among sexual offenders released from prison in New Jersey. The sample of male sex offenders is drawn from the Adult Diagnostic Treatment Center (ADTC), New Jersey's only sex-offender-specific prison, and the general population of nine prisons within the state of New Jersey. The ADTC sample receives treatment while incarcerated (n = 495), whereas no treatment is provided to the offenders in the general population sample (n = 223). Overall, 33% of the total sample (N= 718) commits a new offense. Of the total sample, 14% commits a new sexual offense and 24% commits a new nonsexual offense. Significant differences exist between the ADTC and the general population samples with respect to nonsexual reoffending only. In the final analysis, treatment appears to matter in terms of a reduction in recidivism but not in conventionally expected ways.
516

Lokalt omhändertagande av dagvatten i Västerås - Möjligheter till ökad användning i befintliga innerstadsområden / Local disposal of storm water i Västerås - possibilities for increased use in downtown areas

Matschoss-Falck, Emma January 2013 (has links)
The construction of buildings and paved surfaces changes the natural water balance. Precipitation generates surface runoff and storm water instead of infiltrating into the soil. Storm water has come to be considered as a major source of pollution in lakes and streams in the vicinity of urban areas. Reduction of pollutants in storm water is a key action in order to protect sensitive recipients and maintain high water quality. Storm water is traditionally transported by storm sewers to the nearest recipient. In recent years the approach to storm water management has changed; storm water should primarily be disposed of on site, through local disposal of storm water, LOD. LOD is created by a combination of the function of several smaller local facilities and the general sewer system. In LOD techniques like wet and dry ponds, ditches, rain gardens, infiltration areas and green roofs are used. The function of a LOD facility is reduction, equalization and delay of storm water flows. There are several advantages of LOD over traditional storm water management. The natural water balance is imitated, exposed water surfaces and green areas are perceived as aesthetically pleasing, a reduction of pollutants occurs and the load on the grid is reduced The aim of this work was to investigate the conditions and strategies for increased use of LOD in existing urban areas in Västerås. This was done by examining two areas in Västerås city center and by suggesting LOD solutions. Private land and public land has been distinguished between for each area. The LOD plant is dimensioned so that the total outgoing flow is limited to 10 l / s, hectare. It has been investigated if the requirements for outbound flows from private property can be set lower and flows reduced by a further delay on public land or if it is more advantageous to delay the flows individually. To simulate flow and magazine volumes, the program StormTac has been used. The investigation has shown that storm water volumes to be disposed will be much lower if the disposal is done in one step. Available lawns should be used wherever possible to construct dry ponds, swales or other technics based on infiltration. By using lawns, large volumes can be disposed, pollution is reduced effectively and the arrangement is relatively cheap. Rain gardens are more expensive to construct but provide an efficient cleaning of storm water and are nice from an aesthetic point of view. Rain gardens should be placed lengthwise along roads or pedestrian streets. With such a design, large storage volumes are created while the surrounding areas can still be used. The use of percolation basins are needed when using LOD in urban paved areas. With the use of LOD plants, pollutants are reduced enough to reach the values and goals in Västerås’ storm water plan.
517

Evaluation of the costs of managing cutaneous adverse drug reactions to first-line TB therapy in South African TB patients

Knight, Lauren Kerry January 2018 (has links)
Background: Optimal tuberculosis (TB) treatment remains the backbone of effective TB control programmes. However, TB drugs are often associated with adverse drug reactions (ADR) that affect treatment adherence and cure. Cutaneous adverse drug reactions (CADR) are more commonly associated with Human Immunodeficiency Virus (HIV)/TB co-infection, occurring in up to 7% of patients. If severe, CADR require treatment interruption and hospitalisation. There are no standardised guidelines for managing CADR to TB therapy. Current practice in South Africa involves drug rechallenge, a process, which aims to identify the offending drug and modify the treatment regimen. This practice can carry significant risks that need to be weighed against the benefits. Despite significant resources required to manage CADR, there is no available data regarding their economic impact. Alternate strategies to manage TB therapyassociated CADRs and their cost have never been evaluated. The purpose of this study is to evaluate the economic impact of TB therapy-associated CADRs in South Africa and compare the cost of drug rechallenge with alternative strategies. Methods: Data was obtained from 97 patients, admitted to the Groote Schuur Hospital dermatology ward with TB therapy-associated CADR. Clinical data pertaining to hospitalisation, diagnostic/monitoring tests and drug prescriptions was extracted from patient medical records. Healthcare and patient-related costs were obtained from financial department records, interviews and hospital admission records. Alternative drug regimens for CADR management were derived from literature and expert clinical advice. Costs were estimated using an ingredient's approach in 2016 US dollars. A cost-comparative analysis was performed comparing the cost of the current practice with alternative options. Univariate sensitivity analysis was used to investigate the uncertainties around cost components. Results: The cost of managing a TB therapy-associated CADR was $6,525 per patient. Within this population the average cost of managing a CADR in a patient with DS-TB was $5,831 (95% CI: 8438; 10727). The main contributor of CADR costs was hospitalisation amounting to $3,638/patient (62% of total cost). Alternative CADR management strategies using outpatient-initiated second-line regimens containing rifabutin, bedaquiline and delamanid cost 44-55% less than drug rechallenge depending on the drug regimen used ($2,651/patient to $3,276/patient). Sensitivity analyses indicated that drug rechallenge was most sensitive to hospitalisation costs, whereas second-line treatment strategies were sensitive to TB drug costs. The average total loss experienced by patients as a result of the CADR was $530 (25% of their annual income), as compared to an estimated loss in the alternate regimens of $154 (10% of their annual income). Societal costs with alternate regimens were also lower at 46-66% that of current cost of $6,134. Conclusion: CADR to TB treatment represent a significant economic burden to the healthcare system and affected patient. The alternate strategy of outpatient-initiated second-line therapy provides an economically feasible option by implementing an ambulatory practice of care despite using more expensive drugs. Shorter hospitalisation reduces patient and healthcare costs. This data should inform policy makers on optimal resource use within the healthcare system. Once the effectiveness and risk of drugresistance of these strategies has been determined, further research should estimate their cost-effectiveness.
518

A comparison of the clinician-client interactions in urban language and stuttering clinics

Carnese, Teresa M. 01 January 1977 (has links)
The purpose of this clinical research project was to use an interaction analysis system to compare the behaviors of clinicians and their clients with two types of communicative disorders and to determine how the clinicians utilized their clinical time. More specifically, this study employed the Conover Analysis System (Conover, 1974) and compared the client-clinician behaviors in the Portland State University Urban Language Clinic and Stuttering Clinic. The data which were gathered provided a baseline of the client-clinician behaviors in the two clinical settings.
519

A behavioral treatment program for chronic schizophrenics

Franco, Michelle E. 01 January 1997 (has links)
I examined the effects of a residential treatment program on symptoms and mental health service use in 14 chronic schizophrenics. The clients chosen for this study were the most difficult clients in this population due to continued high service usage (i.e., time spent in locked facilities). All 14 clients had been in a locked facility at least 1 year immediately prior to treatment. The program included skills training, reinforcement for incompatible behavior, and a token economy. The clients' symptomology was recorded twice a day. My hypotheses were that symptoms would decrease due to the program, and clients mental health service use would also decrease in a 1 year follow-up. Mental health service use (time spent in a locked facility) did decrease dramatically after treatment. All 14 clients had a decrease in the amount of time spent in locked facilities after treatment. The total cost for these clients in locked facilities the year immediately prior to treatment was conservatively estimated at $776,500. The annualized figure of the total cost of these 14 clients after treatment was estimated at $44,775, saving San Joaquin County approximately $721,725 in 1 year. The results did not support the hypothesis that the program reliably decreases schizophrenic symptomology as we measured it.
520

TREATMENT OF CONTAMINANTS OF EMERGING CONCERN BY ADVANCED OXIDATION PROCESSES AND REVERSE OSMOSIS

Vilimanovic, Djordje, 0000-0003-3649-5634 January 2022 (has links)
The discussion about contaminants of emerging concern (CECs) is now more prevalent than ever with the ever-increasing topic of non-potable and potable water reuse, especially with direct potable reuse. In the past and today, discharging CECs into an environmental buffer without complete removal is common practice. The Southern and Southwestern United States have been experiencing megadroughts and water shortages and have seen one of the biggest increases in population growth, and these factors put an additional strain on the water demand. Coupled with large, urbanized areas with increased life expectancy (aging population) only contributes to the rise of CECs in the wastewater treatment plants (WWTP) and, subsequently, the surface waters. The CECs previously discharged into the environment can no longer be ignored.This first part of this dissertation was carried out to increase our understanding of the concentration, distribution, occurrence, and potential risk of personal care products (PPCPs) by sampling large and small tributaries of the Delaware River in Pennsylvania. PPCPs are one of the largest categories of CECs and require further investigation. Working from a previous multiyear study conducted by the Delaware River Basin Commission (DRBC) on the main stem of the Delaware River, fifteen compounds were selected based on their high frequency of detection. Ten sampling sites were chosen on tributaries receiving numerous municipal and industrial discharges. Sampling locations were above and below potential source discharges. Sampling was conducted in three different seasons to account for seasonal differences in CECs loadings. The measured environmental concentrations of the target compounds present an insight into the urban and industrial impacts on subwatershed receiving waters. An index for levels of concern (LOC) was applied to the sample locations by comparing measured environmental concentrations, existing target compound water quality criteria, predicted no effects levels, and developing a concern summary variable. All the PPCPs were detected at high frequencies. Triclocarban and diphenhydramine demonstrated to be compounds of high relative risk (RR) to the aquatic life of the Pennsylvania tributaries to the Delaware River. Metformin was labeled low concern but had the highest environmental concentrations and continual presence due to high loading. The second part of the work focused on an unorthodox approach to treating CECs. Advanced oxidation processes (AOPs), specifically ultraviolet (UV) light and hydrogen peroxide (UV/peroxide), were deployed as a pretreatment to the reverse osmosis (RO) feed. The use of AOPs with RO is commonly used in the treatment (polishing) of the permeate and the treatment of the concentrate. As per California’s State Water Resources Control Board, one of the regulatory leaders in water reuse in the US, 1,4-dioxane was utilized as a benchmark to estimate the water reuse processes' efficiency with a minimum 0.5 log10 (69%) reduction. UV/peroxide showed to be an effective AOP in removing multiple CECs in a simulated RO feed. Based on the electric energy per order of removal (EE/O), pretreatment is four-fold more efficient than posttreatment. AdOx™ modeling software was utilized to estimate the treatment kinetics of the feed water and the concentrate. Pretreatment showed to be a viable, more efficient option for treating the CECs with RO compared to the post-treatment of the concentrate and the permeate. / Environmental Engineering

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