600 research outputs found
Climate change and household welfare in rural Tanzania
Der Produktionswert des landwirtschaftlichen Sektors ist in den letzten 30 Jahren in vielen afrikanischen Volkswirtschaften konstant angestiegen, trotzdem herrscht ErnĂ€hrungsunsicherheit weiterhin vor. Dies ist insbesondere fĂŒr Tansania der Fall, wo das Bevölkerungswachstum stĂ€rker war als heimische ProduktionszuwĂ€chse, die vor allem durch die Ausweitung von Land zu landwirtschaftlichen Zwecken erreicht wurden. Bevölkerungsdruck und eine Ăbernutzung von natĂŒrlichen Ressourcen fĂŒhrte zu weitverbreiteter Bodenverschlechterung.
Unter den Bedingungen des Klimawandels haben es Bauern noch schwerer ihren Ertrag zu steigern bzw. stabil zu halten um ihre Familie das ganze Jahr ernĂ€hren zu können. KlimavariabilitĂ€t und eine HĂ€ufung von extremen und wiederkehrenden klimabedingten Schocks wie DĂŒrren und Fluten treten bereits heute in Tansania auf. Einige Bauern passen ihre landwirtschaftlichen Praktiken bereits den verĂ€nderten UmstĂ€nden mithilfe von traditionellen AnpassungsmaĂnahmen an. Politische EntscheidungstrĂ€ger suchen simultan nach nachhaltigen Formen der Intensivierung landwirtschaftlicher Produktion um ErnĂ€hrungssicherung zu gewĂ€hrleisten und gleichzeitig die Ăbernutzung natĂŒrlicher Ressourcen zu begrenzen.
Die vorliegende Arbeit zielt darauf ab zum VerstĂ€ndnis von Anpassungsverhalten beizutragen und die Wirkung verschiedener Anpassungsentscheidungen auf die Wohlfahrt von Kleinbauern in Tansania, insbesondere auf deren ErnĂ€hrungssicherung, zu evaluieren. Im Einzelnen sind die Ziele, (a) die Identifikation der Determinanten der von den Farmhaushalten gewĂ€hlten Strategien als Reaktion auf den wahrgenommenen Klimawandel und deren Implikationen auf die einzelnen Dimensionen der ErnĂ€hrungssicherung; (b) die Ausarbeitung der Verbindung zwischen der Wahrnehmung der tansanischen Kleinbauern von klimatischen VerĂ€nderungen und ihrem Verhalten; und (c) Erkenntnisse zu gewinnen ob nachhaltige Intensivierung fĂŒr die lĂ€ndlichen Kleinbauern in Tansania armutsmindernd ist. Die Arbeit besteht aus vier Kapiteln und basiert hauptsĂ€chlich aus Befragungsdaten von 900 kleinbĂ€uerlichen Haushalten in Tansania, die 2014 und 2016 als Panel erhoben wurden.The production value of the agricultural sector has constantly increased in many African economies over the last thirty years, but food insecurity is still prevailing. This is especially the case for Tanzania, where population growth was stronger than domestic production increases, which were mainly achieved by the expansion into new land for agricultural purpose. Population pressure and an overuse of natural resources as inputs led to widespread soil degradation. Under the changing climatic conditions, farmers are even more challenged to stabilize or even increase their yields in order to provide for their family in any season of the year. Climate variability and an accumulation of extreme and recurring climate-related shocks such as droughts and floods are prevailing in Tanzania. Some farmers already adjust their agricultural practices to these challenges with the application of mainly traditional adaptation measures. Policymakers are simultaneously looking for sustainable forms of intensifying agricultural production to ensure food security while limiting the overuse of natural resources.
The overall objective of this thesis is to contribute to the understanding of the adaptation behavior and to evaluate the impact of different adaptation decisions on the welfare of smallholder farmers in Tanzania, especially on food security. The specific objectives are to (a) identify the determinants of adopting strategies in response to perceived climatic changes by farm households and their implications for different food security dimensions in Tanzania; (b) find evidence on whether sustainable intensification is pro-poor for small-scale farmers in rural Tanzania; and c) elaborate on the link between smallholdersÂŽ perception of climatic changes and their behavior in Tanzania. The thesis consists of four chapters and is mainly based on cross-sectional survey data from 900 small-scale farm households in Tanzania collected in 2014 and partly on the follow-up survey conducted in 2016
Antibody to serotype 8 rotavirus in Ecuadorian and German children
Only 2 out of 71 German patients infected with rotavirus (3%) and 8 out of 147 German control patients (5%) showed serum antibody to the new serotype 8 rotavirus. Such antibody was detected in the sera of 232 of 870 Ecuadorian children (27%). Twelve Ecuadorian sera showed neutralizing activity only against serotype 8 and not to the other serotypes (1-4) tested, indicating that human serotype 8 rotavirus circulates in South Americ
Reactivity of human serum antibody with lipopolysaccharide O 78 antigen from enterotoxigenic Escherichia coli
Fifteen and five of 20 volunteers challenged with the enterotoxigenic Escherichia coli strain O 78·H11 showed a fourfold titre increase of serum ELISA antibody to the homologous O 78 and the heterologous O 8 lipopolysaccharide antigen, respectively. Sixty-three of 191 sera from 1- to 48-month-old German children showed serum antibody reactive with O 78 antigen, all but two of these O 78-positive sera also showed reactivity with at least one further O antigen. Only 14 of the O 78 reactive sera also showed antibody to heat-labile enterotoxin. In addition, soluble O 8 antigen could inhibit the binding of serum antibody to absorbed O 78 in 68% of the German children. Antibody reactive with O 78 antigen is thus not a reliable serological marker for enterotoxigenic E. coli infection in German childre
A strategic approach to value chain upgradingâadopting innovations and their impacts on farm households in tanzania
The level of agricultural productivity in Sub-Saharan Africa remains far below the global average. This is partly due to the scarce use of production-and process-enhancing technologies. This study aims to explore the driving forces and effects of adopting innovative agricultural technologies in food value chains (FVC). These enhancing FVC technologies are referred to as upgrading strategies (UPS) and are designed to improve specific aspects of crop production, postharvest processing, market interaction, and consumption. Based on cross-sectional data collected from 820 Tanzanian farm households, this study utilized the adaptive lasso to analyse the determinants of UPS. To measure the impact of their adoption on well-being, this study applied the propensity score matching approach (PSM). Results from the adaptive lasso suggested that access to credit, experience of environmental shocks and social capital were the main drivers of UPS adoption. In contrast, the engagement in off-farm wage employment impeded adoption. The results from the PSM suggested that UPS adoption has a positive and significant impact on well-being among sampled households, especially with respect to their total value of durable goods and commercialization. The paper suggests that the promotion of social capital and access to financial capital is pivotal in enhancing the adoption of innovative UPS in the farming sector. © 2020 by the authors. Licensee MDPI, Basel, Switzerlan
Psychological responses during the Coronavirus disease (Covid-19) pandemic among optometry and biokinetics students at UJ
M.Tech. (Chiropractic)Abstract: Background There is a lack in sufficient knowledge concerning the psychological responses to the COVID-19 pandemic among Optometry and Biomechanics students at the University of Johannesburg. Aim The aim of the study was to determine the psychological response of Optometry and Biokinetics students at the University of Johannesburg to the COVID-19 pandemic where the psychological responses under investigation were depression, anxiety and stress. Research Methodology This was a cross sectional quantitative exploratory study using the Depression, Anxiety and Stress Scale (DASS-42) as an online questionnaire, with an additional demographic section, via the QuestionProâą platform. It was distributed to the 317 Optometry and Biokinetics students (Optometry comprising of 200 and Biokinetics comprising of 117 students) at the University of Johannesburg. After the relative departments gave their permission to distribute the questionnaire and information documents electronically to the participants. Each participant was required to give consent before completing the questionnaire and take ten minutes to complete the questionnaire. Participants remained anonymous. The data was collected and analysed by the researcher with the assistance of the STATKON department at the University of Johannesburg. Results and Discussion It was concluded in this study that on average, Optometry and Biokinetics students at the University of Johannesburg experienced âmildâ levels of depression and âmoderateâ levels of anxiety and stress during the COVID-19 coronavirus pandemic. The method of measurement was the DASS severity rating scale. The data also showed that the senior students experienced statistically significant higher..
Transcription Analysis of Streptococcus thermophilus Phages in the Lysogenic State
AbstractThe transcription of prophage genes was studied in two lysogenic Streptococcus thermophilus cells by Northern blot and primer-extension experiments. In the lysogen containing the cos-site phage Sfi21 only two gene regions of the prophage were transcribed. Within the lysogeny module an 1.6-kb-long mRNA started at the promoter of the phage repressor gene and covered also the next two genes, including a superinfection exclusion (sie) gene. A second, quantitatively more prominent 1-kb-long transcript was initiated at the promoter of the sie gene. Another prophage transcript of 1.6-kb length covered a group of genes without database matches that were located between the lysin gene and the right attachment site. The rest of the prophage genome was transcriptionally silent. A very similar transcription pattern was observed for a S. thermophilus lysogen containing the pac-site phage O1205 as a prophage. Prophages from pathogenic streptococci encode virulence genes downstream of the lysin gene. We speculate that temperate phages from lactic streptococci also encode nonessential phage genes (âlysogenic conversion genesâ) in this region that increase the ecological fitness of the lysogen to further their own evolutionary success. A comparative genome analysis revealed that many temperate phages from low GC content Gram-positive bacteria encode a variable number of genes in that region and none was linked to known phage-related function. Prophages from pathogenic streptococci encode toxin genes in this region. In accordance with theoretical predictions on prophageâhost genome interactions a prophage remnant was detected in S. thermophilus that had lost most of the prophage DNA while transcribed prophage genes were spared from the deletion process
Effective prophylaxis against rotavirus diarrhea using a combination of Lactobacillus rhamnosus GG and antibodies
<p>Abstract</p> <p>Background</p> <p>Rotavirus is a worldwide cause of infectious infantile diarrhea that claims over 600,000 lives annually. Recently, two new vaccine candidates have been developed but their efficacy in developing countries, still remains to be proven. Oral delivery of specific immunoglobulins provides passive immunity and is a fast acting treatment for rotavirus diarrhea. Probiotic bacteria have also gained considerable attention lately as treatment for rotavirus diarrhea. Here we report an evaluation of the therapeutic potential of different probiotics and their combination with anti â rotavirus antibodies in a mouse model of rotavirus diarrhea.</p> <p>Results</p> <p>Of the six probiotic bacteria tested, <it>Lactobacillus rhamnosus </it>strain GG had the strongest influence in reducing prevalence, duration and severity of diarrhea and was therefore chosen for combination treatment with immunoglobulins. The combination treatment reduced the diarrhea outcome measures significantly, prevented histopathological changes and reduced the virus load in the intestines.</p> <p>Conclusion</p> <p>The advantages associated with immunoglobulins and probiotics based therapy is that the treatment provides a rapid therapeutic effect and is cost efficient. These components do not require special storage conditions and could potentially complement the rehydration therapy that is currently used.</p
Widespread distribution of a group I Intron and Its three deletion derivatives in the Lysin Gene of Streptococcus thermophilus Bacteriophages.
Of 62 Streptococcus thermophilus bacteriophages isolated from various ecological settings, half contain a lysingene interrupted by a group IA2 intron. Phage mRNA splicing was demonstrated. Five phages possess a variantform of the intron resulting from three distinct deletion events located in the intron-harbored open readingframe (orf 253). The predicted orf 253 gene sequence showed a significantly lower GC content than thesurrounding intron and lysin gene sequences, and the predicted protein shared a motif with endonucleasesfound in phages from both gram-positive and gram-negative bacteria. A comparison of the phage lysin genesrevealed a clear division between intron-containing and intron-free alleles, leading to the establishment of a14-bp consensus sequence associated with intron possession. The conserved intron was not found elsewhere inthe phage or S. thermophilus bacterial genomes. Folding of the intron RNA revealed secondary structureelements shared with other phage introns: first, a 38-bp insertion between regions P3 and P4 that can be foldedinto two stem-loop structures (shared with introns from Bacillus phage SPO1 and relatives); second, aconserved P7.2 region (shared with all phage introns); third, the location of the stop codon from orf 253 in theP8 stem (shared with coliphage T4 and Bacillus phage SPO1 introns); fourth, orf 253, which has sequencesimilarity with the H-N-H motif of putative endonuclease genes found in introns from Lactococcus, Lactobacillus,and Bacillus phages
Influence of unilateral ovariectomy performed before ovulation on ovarian function, steroid hormone levels and development of porcine fetuses
Corpus luteum (CL) activity is closely linked with initiation and maintenance of pregnancy and with fetal development. The present study was aimed to analyze the impact of unilateral ovarian removal on ovarian function, steroid hormone level and fetal distribution and development. Unilateral ovariectomy (uni-OVX) was performed in gilts one day before ovulation (group SHORT, n = 24), 20 days before subsequent ovulation (group LONG, n = 23) or ovaries remained intact (group INTACT, n = 22). Gilts were inseminated by single fixed-time laparoscopic intrauterine insemination (LIUI) after hormonal estrus synchronization. Two days before the end of a 15 day long altrenogest feeding, a part of gilts (n = 23) were surgically fitted with a jugular vein catheter and blood samples were collected to determine of estradiol (E2) and progesterone (P4) concentrations. All animals were slaughtered on day 30 of gestation and ovarian features as well as the number, weight and distribution of fetuses recorded. Altogether, 48 gilts (70%) were pregnant and pregnancy rates did not differ between groups. Short term uni-OVX affected CL number compared to intact and long term OVX gilts (9.9 ± 0.8 vs. 20.6 ± 1.9 and 17.5 ± 0.8; P < 0.05) and the number of fetuses (8.7 ± 0.5 vs. 15.0 ± 1.0 and 14.4 ± 1.1; P<0.05), respectively. Weights of individual CL were not influenced by treatment. Fetuses were differently distributed in the uterine horns after uni-OVX. A higher (P<0.05) proportion of fetuses was present always in the horn which bore the ovary. In all groups, weights of fetuses from uterine horns with an active ovary was similar; however, fetuses of the OVX horn of the SHORT group were lighter (P < 0.05). Steroid hormone profile was typical for pregnant gilts, but differences were observed between groups. Both, the preovulatory E2 concentrations and the early luteal phase P4 levels were higher (P < 0.05) in gilts of the INTACT and LONG groups. In summary, compared to intact gilts, only long term uni-OVX could compensate ovarian development. Short term uni-OVX affects (1) the total number of CL and fetuses, (2) the distribution and weight of fetuses in the uterine horns and (3) steroid hormone levels. Therefore, the time window, but not the uni-OXV per se, which alters the local supply of progesterone, has an impact on fetal development and survival
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