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Investigating sustainable mitigation alternatives for groundwater in Matlab Upazila, Bangladesh. : A Minor Field Study. / Undersökning av hållbara åtgärdsalternativ för grundvatten i Matlab Upazila, Bangladesh. : En fältstudie (Minor Field Study).Gingborn, Nicklas, Wåhlén, Hanna January 2012 (has links)
Since the late 20th century most people in rural Bangladesh use hand pumped tube wells to extract groundwater as their primary source of water. In 1993 it was officially recognized that many of the Holocene groundwater aquifers contain elevated levels of arsenic (As) and that millions of people in Bangladesh are exposed and at risk for mass poisoning. The need to focus efforts to areas with scarce supply of safe drinking water has raised the need to quickly locate and identify these areas. Mitigation options evaluated in this study focus on 1) how to target As safe aquifers and 2) how to identify As safe tube wells An attempt to target As safe shallow aquifers based on sediment color was evaluated. The majority of 30 new tube wells screened in off-white sand sediments have As safe water with respect to both the WHO and the national guideline, but including the failed attempts to target off-white sediments at shallow depths, the success rate of the method was considered to be too low. This study also attempt to validate platform color as a rapid low-cost screening tool for As by relating platform color to water chemistry in 103 tube wells. Different classification methods were tested to develop recommendations for the future use of this method. The results showed that a simplified color classification was better than a detailed classification at predicting water chemistry of iron (Fe), manganese (Mn) and As. Recently, Mn has also emerged as a possible widespread problem in the Bengal Basin. Although not thoroughly investigated, present evidence indicates that a high concentration of Mn in drinking water affects the intellectual function in children. The occurrence of both low As and low Mn concentrations in shallow aquifers was found to be very unlikely since only one out of 133 tested wells had this water chemistry composition. Instead it was showed that the highest Mn concentrations occur in As-safe aquifers. Therefore WHO should consider reintroducing their previous health based guideline value for Mn to highlight the potential risk of excessive exposure, since more people risk being exposed to Mn when As-safe shallow aquifers are targeted.
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Effectiveness of Tubewell platform color as screening tool for arsenic and manganese in drinking water wells: An assessment from Matlab region Southeastern Bangladesh.Annaduzzaman, Md January 2012 (has links)
Arsenic (As) contamination in groundwater is a severe and adverse water quality issue for drinking purposes, particularly in Southeast Asia, where groundwater is the main drinking water source. Bangladesh is one of the countries where arsenic poisoning in groundwater is massive and it is essential to find out a reliable alternative safe drinking water source. In this process, it is very much needed to identify As-rich wells to avoid drinking water from them and to assess the extent of contamination as well. This study attempts to evaluate the potentiality of tube-well (TW) platform color as low-cost quick screening tool for As and Mn as well in drinking water wells (n=272). The result shows strong association of red color platform with As-rich water in the corresponding wells compared to WHO guideline value of 10 μg/L (98.7% certainty) and regional (Bangladesh/India) standard of 50 μg/L (98.3% certainty). The sensitivity and efficiency of red color platforms to screen high As water in TW for 10 μg/L are 98% and 97%. Similarly, for 50 μg/L, it is 98% for both sensitivity and efficiency. However, because of a very low number (n=4) of TW platform stained with black color, it is not possible to make any conclusion on the potentiality of black color as a screening tool for Mn. This study suggests that red colored platform can be potentially used for primary identification of TWs with elevated As concentration and to prioritise sustainable As mitigation management. However, this study does not discard the concept of black colored platform as a screening tool for Mn-rich water. Further study is recommended to evaluate the efficiency of black color as a screening tool for Mn.
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Sediment State and Flow – An Investigation of Sediment Pollution and Transport in the Bîc River, Republic of Moldova. : A Minor Field Study.Gillefalk, Mikael, Lindberg, Felix January 2013 (has links)
The Bîc River in the Republic of Moldova is a heavily polluted water body. Along the river stretch, from a small creek in Sipoteni close to the river mouth at Gura Bîcului, sediment samples were taken using a very cost-effective method and analyzed for a number of pollutants. The results showed very high levels of petroleum products in and downstream of the city of Chişinău, situated in the middle of the river basin, ex-ceeding even the guideline value for cleanup of industrial land. Concentrations of heavy metals were detected at all sample points, exceeding the Lowest Effect Level (LEL) in 37 out of 48 samples and the Probable Effect Level (PEL) in four of them. High concentrations of nutrients (N and P) were detected, especially outside of the city, where concentrations exceeded even the Severe Effect Level (SEL) for both N and P at one site. DDT concentrations were highest at the beginning of the river, the concentrations becoming lower and lower when getting closer to the river mouth. At three of the six sampling sites, DDT concentrations exceeded the LEL. PCB levels were lower than the LEL. This was attributed to unsuitable handling of the samples before analysis and therefore the PCB concentration levels requires further investiga-tion. The continued monitoring of the sediments is of great need, therefore a proposal for a monitoring program was written. It was estimated that Bîc contributes 118000 tons of suspended particles to Dniester each year, almost 60 % more per km2 than Dniester contributes to the Black Sea.
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Delivery Systems to Enhance Neural Regeneration in the Central Nervous SystemStumpf da Silva, Taisa Regina 10 July 2019 (has links)
The central nervous system (CNS) is susceptible to several disorders that can affect the structure or function of the brain or spinal cord, such as stroke and spinal cord injury (SCI). CNS disorders are complex, frequently causing failure of cognitive, motor and sensory functions. Unfortunately, there are only a few care alternatives for patients with CNS disorders, due to the limited capacity of the CNS to spontaneously regenerate; what expresses the need to develop innovative solutions, such as scaffolds that also could act as drug delivery systems to promote tissue and functional repairs in the CNS. To achieve this goal, three main projects were developed in this thesis. In the first project, a novel drug releasing duraplasty that can be applied as part of decompressive craniectomy (DC) was designed and tested. While DC can significantly reduce the risk of death, this procedure does not reverse the stroke damage. Thus, biosynthesized cellulose (BC) was used to produce a new duraplasty loaded with growth factors. The in vivo animal studies revealed that our duraplasty had excellent biocompatibility when implanted onto rodents’ brains. In the second project, BC tubes were prepared and nerve growth factor was incorporated into the tubes to be used as potential nerve guides to assist with the reconstitution of nerve tissues across SCI lesion. Physical and mechanical properties of the drug delivery systems produced were evaluated and compared to the neural native tissue. In addition, cell cultures demonstrated that growth factors released from both drug delivery systems were bioactive for over 7 days. In the third project, linear and 2-branched peptides were synthesized as potential bioactive molecules to improve tissue regeneration. These peptides, containing the RGDS sequence, were synthesized through Solid Phase Peptide Synthesis and characterized by mass spectrometry, high-performance liquid chromatography, and their conformational structures were analyzed by an energy minimized 3D model. In summary, this thesis explores the use of BC as drug releasing systems, which are promising and clinically relevant strategies to enhance nerve regeneration for many patients facing physical, mental and financial strains due to stroke, SCI or other difficult-to-cure injuries to the CNS.
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Tube-tap or Earliest Due Date : What happens when all jobs cannot be completed?Sparrman, Victoria January 2021 (has links)
In this thesis the scheduling algorithms Earliest Due Date (EDD) and Tube-tap were compared to each other. They were compared to see which algorithm generated more net profit. They were compared to each other in four different scenarios. In each scenario there were two different machines and five different jobs. Each machine had a cost and a processing rate, and each job had a length, a deadline, and a profit. In every scenario all jobs could not be completed before their deadline. The net profit was calculated by subtracting the gross profit by the machine cost. The results for the Tube-tap and EDD algorithms were almost the same for both algorithms in the different scenarios. There was one scenario where Tube-tap gained 0.5 more in profit. This was because Tube-tap had 0.5 in machine cost for one of the scenarios. The conclusions was that there should be more experimentation to see how more profitable Tube-tap can be. Specifically, there should be testing on scenarios where all jobs cannot be completed before their deadlines, but the number of operations does not exceed the available space before the last deadline.
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Association between Feeding Difficulties and Length of Hospital Stay among Infants Diagnosed with Neonatal Opioid Withdrawal SyndromeSodeke, Patrick Olumuyiwa, Bhetuwal, Kanta, Chroust, Alyson, Johnson, Michelle, Shah, Darshan 04 May 2020 (has links)
Background: The incidence of neonatal opioid withdrawal syndrome (NOWS), a drug withdrawal syndrome mainly associated with opioid exposure in-utero has significantly increased in the United States over the last decade with infants with NOWS staying longer in the hospital than those without NOWS. Objectives: To determine if feeding tube use while on admission is associated with length of hospital stay among infants diagnosed with NOWS. We also compared the differences between infants with NOWS who required the use of feeding tubes while on admission, and those that did not, based on infant and maternal characteristics. Methods: This was a retrospective cohort study of infants delivered between July 1, 2011 and June 30, 2016 at Ballad Health System. Our inclusion criteria were infants who were exposed to opioids in-utero and received a diagnosis of NOWS based on 2 consecutive Finnegan scores of 10, or 3 consecutive scores of 8, or treatment with morphine. Medical chart record of 294 infants who met these criteria were reviewed for infant and maternal characteristics. Our outcome variable was infant length of hospital stay and our predictor variable was feeding tube use an indicator for feeding difficulties. Chi-square test and t-test were used to compare infant and maternal characteristics by feeding tube use. Simple linear regression models were used to assess the effect of feeding tube use and infant and maternal characteristics on infant length of hospital stay. Multiple linear regression was used to model infant length of hospital stay predicted by feeding tube use, while adjusting for neonatal intensive care unit (NICU) admission, treatment with morphine, and maternal benzodiazepine use during pregnancy. All analyses were done using SAS 9.4. Results: Of the 294 infants diagnosed with NOWS, 22.11% had feeding difficulties that necessitated use of feeding tubes. Infants who used feeding tubes were significantly more likely to be born preterm (20.31% vs 8.73%, p=0.0096) to be admitted into the NICU (98.46% vs 51.09%, p=
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The prevalence of neural tube defects and the outcome of myelomeningocele in Cape TownBuccimazza, Sandro Sabatino 07 April 2017 (has links)
This study was designed to document the prevalence of neural tube defects in Cape Town and to determine the outcome of children born with a myelomeningocele and operated on within the Neurosurgical service of the University of Cape Town. The aim of the prevalence study was to document the frequency of neural tube defects (NTD) over a twenty year period in Cape Town (1973 - 1992) and to determine the effects of race, gender, maternal age, parity, and season of conception on the prevalence. Multiple sources of ascertainment were used, including all maternity hospital records, neurosurgical and spinal defects clinic data, as well as those from the Human Genetics Department and Fetal Abnormality Group. The prevalence rates for NTD fluctuated between 1,74 and 0,63 per 1 000 births, but showed no significant trends over the twenty year period. Prevalence rates were highest for the white population group at 2,56 per 1 000 births compared to 0,95 per 1 000 for blacks and 1,05 per 1 000 for those of mixed ancestry. The higher rates in the whites, who are of British and European extraction and belong to the more affiuent section of the community, would suggest that the possible effects of nutrition and infection are overshadowed by genetic factors. There was a female preponderance for both spina bifida (M:F ratio 0,89) and anencephaly (M:F ratio 0,67). The highest NTD rates were found at both ends of the maternal age range (<20 years and >35 years of age). The prevalence was highest at the extremes of birth order (1,65 and 1,58 for birth order 1 and >7, respectively, and 0,56 and 0,45 for birth order 5 and 6, respectively). A seasonal variation occurred which differed from that reported for the Northern Hemisphere and may reflect local climatic conditions. The aim of the outcome study was to follow a group of infants who were operated on for myelomeningocele (01 January 1979 - 31 December 1985) and evaluate their outcome at five years of age, in an attempt to identify factors that may influence the quality of survival and their outcome, and to utilise these findings to recommend altering and improving ( where possible) the management of children born with myelomeningocele.
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Patienters erfarenheter och upplevelser av att få enteral nutrition via nasogastrisk sond : En litteraturstudie / Patients’ experiences of enteral tube feeding via nasogastric tube : A literature studyTranberg, Julia, Rydberg, Caroline January 2020 (has links)
Bakgrund: Enteral nutrition via nasogastrisk sond är en vanlig behandlingsform för kortsiktig nutritionsbehandling då den anses ha förhållandevis lätt inläggning och avlägsnande. Sondinläggning och behandling kan innebära risker som kan leda till aspiration och allvarliga infektioner. Syfte: Syftet var att beskriva vuxna patienters erfarenheter och upplevelser av näringstillförsel via nasogastrisk sond. Metod: En allmän litteraturstudie genomfördes. Nio vetenskapliga artiklar med kvalitativ ansats bearbetades i en innehållsanalys. Resultat: Innehållsanalysen presenterar fyra teman: Erfarenheter och upplevelser av fysiskt obehag, Erfarenheter och upplevelser av ett begränsat liv, Erfarenheter och upplevelser av en förändrad identitet samt Erfarenheter och upplevelser av att hantera vardagen. Deltagare beskrev upplevelser av fysiskt obehag vid insättning av sonden och under själva behandlingen, samt erfarenheter av begränsningar i vardagen och uttryckte även en ovilja att lämna hemmet. Vidare beskrevs upplevelser av en försämrad självbild relaterat till sondens synliga placering samt copingstrategier och behovet av stöd från sjukvårdspersonal och familj. Slutsats: Deltagarna upplevde både positiva och negativa erfarenheter och upplevelser vilket resulterade i motstridiga känslor. Ett individanpassat stöd från sjukvårdpersonal kan ha stor inverkan på deltagarnas välbefinnande och möjlighet till att klara sitt dagliga liv. / Background: Enteral nutrition via nasogastric tube is a common treatment form for short-term nutritional support since intubation and removal are rather simple to perform. Tube intubation and treatment may entail risks of aspiration and serious infections. Aim: The aim was to describe adult patients' experiences of nutritional support via nasogastric tube. Method: A general literature study was implemented. Nine articles with a qualitative approach were analyzed through content analysis. Results: The content analysis present four themes: Experiences of physical discomfort, Experiences of a limited life, Experiences of a changed identity and Experiences of dealing with everyday life. Participants described experiences of physical discomfort during insertion and the treatment itself, and experiences of limitations in their everyday lives and expressed a reluctance to leave their homes. Furthermore, experiences of an impaired self-image related to the tube’s visible location was described as well as coping strategies and a need for support from healthcare personnel and family. Conclusion: Participants described both positive and negative experiences, which resulted in conflicted emotions. Receiving personalized support from healthcare personnel can have a major impact on the participants' well-being and ability to cope with their everyday lives.
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Germania-Based Sol-Gel Organic-Inorganic Hybrid Coatings for Capillary MicroextractionFang, Li 01 April 2009 (has links)
For the first time, germania-based hybrid organic-inorganic sol-gel materials were developed for analytical sample preparation and chromatographic separation. Being an isostructural analog of silica (SiO2), germania (GeO2) is compatible with silica network. This structural similarity, which is reflected by the relative positions of germanium and silicon in the periodic table, stimulated our investigation on the development of germania-based sol-gel hybrid organic-inorganic coatings for analytical applications.
Sol-gel sorbents and stationary phases reported to date are predominantly silica-based. Poor pH stability of silica-based materials is a major drawback. In this work, this problem was addressed through development of germania-based organic-inorganic hybrid sol-gel materials. For this, tetramethoxygermane (TMOG) and tetraethyoxygermane (TEOG) were used as precursors to create a sol-gel network via hydrolytic polycondensation reactions to provide the inorganic component (germania) of the organic-inorganic hybrid coating. The growing sol-gel germania network was simultaneously reacted with an organic ligand that contained sol-gel-active sites in its chemical structure. Hydroxy-terminated polydimethylsiloxane (PDMS) and 3-cyanopropyltriethoxysilane (CPTES) served as sources of nonpolar and polar organic components, respectively. The sol-gel reactions were performed within fused silica capillaries. The prepared sol-gel germania coatings were found to provide excellent pH and thermal stability. Their extraction characteristics remained practically unchanged after continuous rinsing of the sol-gel germania-PDMS capillary for 24 hours with highly basic (pH=13) and/or acidic (pH = 1.3) solution. They were very efficient in extracting non-polar and moderately polar analytes such as polycyclic aromatic hydrocarbons, aldehydes, ketones. Possessing the polar cyanopropyl moiety, sol-gel germania cyanopropyl-PDMS capillaries were found to effectively extract polar analytes such as alcohols, fatty acids, and phenols. Besides, they also showed superior thermal stability compared with commercial cyano-PDMS coatings thanks to the covalent attachment of the coating to capillary surface achieved through sol-gel technology. Their extraction characteristics remained unchanged up to 330°C which is significantly higher than the maximum operation temperature ( < 280 ºC) for commercial cyano-PDMS coatings. Low ng/L detection limits were achieved for both non-polar and polar test solutes. Our preliminary results also indicated that sol-gel hybrid germania coatings have the potential to offer great analytical performance as GC stationary phases.
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Optimization of modular die design in extrusion processBakhtiani, Tushar P. January 2015 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Aluminum extrusion is a metal forming process used for the production of a large
variety of solid, semi-solid and complex hollow products. During extrusion, the hot
aluminum billet goes under severe plastic deformation as it is forced to flow through a
smaller die cavity that defines the final shape of the extruding product. Surface finish and
dimensional accuracy are the two most important criteria that specify the productivity and
feasibility of the extrusion process which is highly influenced by the flow of aluminum
through the deforming die. Therefore, die design is considered as one of the most
important characteristics of the extrusion process that influences aluminum flow, quality
of the extruding product and its dimensional accuracy.
Currently, development of extrusion dies is primarily based upon the empirical
knowledge of the die designer gained through trial and error, which inevitability is an
expensive, time consuming and ineffective method. However, owing to the technological
advancements of this century in the field of finite element modeling, this decade old trial
and error method can now be replaced by numerical simulations that not only save time
and money but also, can accurately predict the flow of aluminum through a die as well as
predict die deformation occurring during the extrusion process The motivation of this
research project came from a private extrusion die manufactures need for improving their
pioneered modular die based on good analytical and scientific understanding of the dies
performance during the extrusion process.
In this thesis, a commercial simulation package Deform 3D is used to simulate the
thermo-mechanical interactions of aluminum flow through the deforming modular die for
the production of Micro Multi-Port (MMP) tubes.
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