157 research outputs found
Conflict over Scarce Economic Resources: An Analysis of the Zimbabwe/Nigeria Small-Scale Business Relationship in Harare
Zimbabwe is currently undergoing a difficult economic phase where unemployment rate is over 85% and the economy is largely informal. The few formal business operations are in the hands of few foreigners who established themselves during the 2007-2009 economic crises when most Zimbabweans were economically down and crippled. The study sought to establish the relationship between the disempowered Zimbabweans and the few empowered foreigners with a view to establish the volatility vis-Ã -vis the situation in the neighbouring South Africa regarding xenophobia. The study was conducted in Harare through a mixed method approach which saw 10 key participants drawn from both Zimbabwean and Nigerian business operators being interviewed. To compliment interviews, policy documents and other relevant literature was reviewed. Data was analysed using Constant Comparison method based in grounded theory approach. The study did confirm the dominance by foreigners in business operations and the existence of an aggrieved voice within the Zimbabwean citizens. However, it also established that the possibility of a Zimbabwe/Nigeria conflict is far-fetched given available conditions. Keywords: economic resources, xenophobia, unemployment, immigrants, investments, conflict
Pengaruh Radiasi Sinar Gamma Terhadap Kultur in Vitro Tanaman Jahe
In vitro shoot explants of white ginger and red ginger are irradiated by two different techniques. The first, the tuber explants are irradiated by 2 levels of gamma rays namely 10 and 30 Gy. The second, the shoot explants are irradiated by 2 levels of gamma rays namely 7,5 and 12,5 Gy. The irradiated explants are regenerated on modified MS medium with BAP 2 ppm and NAA 0,25 ppm. The result show that the irradiated tuber explants with 10 and 30 Gy could not initiate new regenerant of ginger. On the other hand the irradiated shoot explants with 7,5 and 12,5 Gy have been able to influence the growth and development of shoot, leaf and root. It is indicated that the level of gamma rays irradiation on shoot explants influences the induced putative mutant of ginger. However, the sprouting of red ginger on 12,5 Gy is higher and faster than 7,5 Gy, and white ginger as well as control. The other morphological characters have not been able to be identified, the experiment are still in process to detect the mutagenic influences
Investigating the cooling rate of cane molasses as quenching medium for 0.61% C high carbon steels
The effect of cooling rate of cane molasses as quenching medium for 0.61% C high carbon steels was investigated. Samples of high carbon steel were spheroidized annealed and then machined prior to the hardening process. Molasses solution of viscosity equals to that of engine oil was prepared by adding water. The samples were normalized and then austenitised at 800oC and soaked for 40 minutes and then quenched in water, engine oil, raw molasses and the prepared molasses solution. Cooling rate curves of all the quenching media used were developed. The highest cooling rate of 60oC/s was attained by the prepared molasses solution. Hardness of the test samples was evaluated. The test results obtained show that the highest hardness value (525 HVN) was obtained from the sample quenched in the prepared molasses solution. Microstructures of the various samples were analyzed using OM and SEM. In all the tests samples martensite structure was observed. It was observed that the prepared molasses solution has higher severity of quenching than that of engine oil but lower than that of water. The research showed that cane molasses can harden high carbon steel without cracking the component in the same way as engine oil, hence, molasses could be a very good alternative to engine oil for use as quenching medium
Survey of the fatty acid composition of peanut (arachis hypogaea) germplasm and characterization of their epoxy and eicosenoic acids
Peanut (Arachis hypogaea) plant introductions (732) were analyzed for fatty acid composition. Palmitate varied from 8.2 to 15.1%, stearate 1.1 to 7.2%, oleate 31.5 to 60.2%, linoleate 19.9 to 45.4%, arachidate 0.8 to 3.2%, eicosenoate 0.6 to 2.6%, behenate 1.8 to 5.4%, and lignocerate 0.5 to 2.5%. The eicosenoate was shown to be cis-11-eicosenoate. In addition, epoxy fatty acids were found in many plant introductions in percentages ranging as high as 2.5%. These were tentatively identified as chiefly 9,10-epoxy stearate and coronarate with smaller amounts of vernolate. The percentage of palmitate was shown to be correlated positively with linoleate and negatively with oleate, eicosenoate, and lignocerate. Stearate was highly correlated with arachidate and negatively with eicosenoate and lignocerate. Oleate and linoleate, the two major fatty acids, were negatively correlated. Arachidate was negatively correlated with eicosenoate, and eicosenoate was positively correlated with lignocerate. Behenate and lignocerate were positively correlated. Epoxy esters were positively correlated with palmitate and negatively with oleate. Segregation of the plant introductions by axis flower, growth habit, and pod types showed significant differences that reflected the same fatty acid groupings revealed by the correlations
Investigating the cooling rate of cane molasses as quenching medium for 0.61% C high carbon steels
The effect of cooling rate of cane molasses as quenching medium for 0.61% C high carbon steels was investigated. Samples of high carbon steel were spheroidized annealed and then machined prior to the hardening process. Molasses solution of viscosity equals to that of engine oil was prepared by adding water. The samples were normalized and then austenitised at 800oC and soaked for 40 minutes and then quenched in water, engine oil, raw molasses and the prepared molasses solution. Cooling rate curves of all the quenching media used were developed. The highest cooling rate of 60oC/s was attained by the prepared molasses solution. Hardness of the test samples was evaluated. The test results obtained show that the highest hardness value (525 HVN) was obtained from the sample quenched in the prepared molasses solution. Microstructures of the various samples were analyzed using OM and SEM. In all the tests samples martensite structure was observed. It was observed that the prepared molasses solution has higher severity of quenching than that of engine oil but lower than that of water. The research showed that cane molasses can harden high carbon steel without cracking the component in the same way as engine oil, hence, molasses could be a very good alternative to engine oil for use as quenching medium
Noninvasive assessment of patients undergoing percutaneous intervention in myocardial infarction
FUNDAMENTO: A reestenose pós-intervenção coronariana percutânea primária permanece um problema de relevância clÃnica, mesmo com o implante de stents. A capacidade das provas não invasivas para detecção de reestenose não foi totalmente demonstrada. OBJETIVO: Avaliar a habilidade do teste ergométrico (TE) e da cintilografia de perfusão miocárdica (CPM) no diagnóstico de reestenose em pacientes com infarto agudo do miocárdio, e supradenivelamento do segmento ST, submetidos à angioplastia coronariana percutânea primária (ACPP), com implante de stent nas primeiras 12 horas de evolução. MÉTODOS: De Ago/2003-Jan/2006, foram selecionados 64 pacientes (ps) (56,2 ± 10,2 anos, 53 homens) submetidos à ACPP. Apenas ps com fração de ejeção do ventrÃculo esquerdo > 40,0%, definida por ecocardiograma de repouso, foram incluÃdos. Teste ergométrico, com as 12 derivações do ECG associadas a precordiais direitas, e CPM foram realizados 6 semanas, 6 meses e um ano após o tratamento. Foi realizada cinecoronariografia no 6º mês. RESULTADOS: Doença uniarterial ocorreu em 46,9% dos ps, sendo a artéria descendente anterior tratada em 48,4%. Reestenose angiográfica ocorreu em 28,8%. Sensibilidade, especificidade, valor preditivo positivo (VPP), valor preditivo negativo (VPN) e acurácia do TE para detecção de reestenose não foram significativos. A adição de derivações precordiais direitas não proporcionou informações adicionais. Sensibilidade, especificidade, VPP, VPN e acurácia da CPM apresentaram correlação com reestenose apenas no 6º mês, considerando-se summed difference score > 2 (p = 0,006) e > 4 (p = 0,014). CONCLUSÃO: O TE não discriminou reestenose. A CPM realizada no 6º mês foi relacionada à reestenose e mostrou-se útil durante a evolução.BACKGROUND: Restenosis after primary percutaneous coronary intervention (PPCI) remains an important clinical problem, even with stent implantation. The ability of noninvasive testing to diagnose restenosis has had only inconsistent demonstration. OBJECTIVE: Our objective was to evaluate the ability of exercise treadmill testing (ETT) and myocardial perfusion imaging (MPI) to diagnose restenosis in patients treated by PPCI within 12 hours of ST-elevation myocardial infarction (STEMI). METHODS: From August 2003 to January 2006, 64 patients (mean age of 56.2±10.2 years, 53 males) were enrolled after PPCI. Only patients with left ventricular ejection fraction (LVEF) > 40%, as assessed by resting transthoracic echocardiography (TTE), were included. ETT with 12-lead ECG monitoring and right precordial leads, as also MPI were performed at 6 weeks, 6 months, and one year after intervention. Coronary angiography was performed at six months. RESULTS: Single-vessel disease was observed in 46.9% of the patients. The left anterior descending coronary artery was treated in 48.4% of the patients. Angiographic restenosis occurred in 28.8%. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of ETT in detecting restenosis were not significant. Right precordial leads did not add information. MPI sensitivity, specificity, PPV, NPV, and accuracy correlated with restenosis only in the 6-month follow-up, both when considering summed difference score >2 (p=0.006) and >4 (p=0.014). CONCLUSION: ETT did not discriminate restenosis in this population. MPI performed at 6 months correlated with restenosis and proved useful during follow-up
Color-scalable flow cytometry with Raman tags
Flow cytometry is an indispensable tool in biology and medicine for counting and analyzing cells in large heterogeneous populations. It identifies multiple characteristics of every single cell, typically via fluorescent probes that specifically bind to target molecules on the cell surface or within the cell. However, flow cytometry has a critical limitation: the color barrier. The number of chemical traits that can be simultaneously resolved is typically limited to several due to the spectral overlap between fluorescence signals from different fluorescent probes. Here, we present color-scalable flow cytometry based on coherent Raman flow cytometry with Raman tags to break the color barrier. This is made possible by combining a broadband Fourier-transform coherent anti-Stokes Raman scattering (FT-CARS) flow cytometer, resonance-enhanced cyanine-based Raman tags, and Raman-active dots (Rdots). Specifically, we synthesized 20 cyanine-based Raman tags whose Raman spectra are linearly independent in the fingerprint region (400 to 1,600 cm-1). For highly sensitive detection, we produced Rdots composed of 12 different Raman tags in polymer nanoparticles whose detection limit was as low as 12 nM for a short FT-CARS signal integration time of 420 µs. We performed multiplex flow cytometry of MCF-7 breast cancer cells stained by 12 different Rdots with a high classification accuracy of 98%. Moreover, we demonstrated a large-scale time-course analysis of endocytosis via the multiplex Raman flow cytometer. Our method can theoretically achieve flow cytometry of live cells with >140 colors based on a single excitation laser and a single detector without increasing instrument size, cost, or complexity
Subjects with Knee Osteoarthritis Exhibit Widespread Hyperalgesia to Pressure and Cold
Hyperalgesia to mechanical and thermal stimuli are characteristics of a range of disorders such as tennis elbow, whiplash and fibromyalgia. This study evaluated the presence of local and widespread mechanical and thermal hyperalgesia in individuals with knee osteoarthritis, compared to healthy control subjects. Twenty-three subjects with knee osteoarthritis and 23 healthy controls, matched for age, gender and body mass index, were recruited for the study. Volunteers with any additional chronic pain conditions were excluded. Pain thresholds to pressure, cold and heat were tested at the knee, ipsilateral heel and ipsilateral elbow, in randomized order, using standardised methodology. Significant between-groups differences for pressure pain and cold pain thresholds were found with osteoarthritic subjects demonstrating significantly increased sensitivity to both pressure (p = .018) and cold (p = .003) stimuli, compared with controls. A similar pattern of results extended to the pain-free ipsilateral ankle and elbow indicating widespread pressure and cold hyperalgesia. No significant differences were found between groups for heat pain threshold, although correlations showed that subjects with greater sensitivity to pressure pain were also likely to be more sensitive to both cold pain and heat pain. This study found widespread elevated pain thresholds in subjects with painful knee osteoarthritis, suggesting that altered nociceptive system processing may play a role in ongoing arthritic pain for some patients
Characterization of the correlated background for a sterile neutrino search using the first dataset of the JSNS experiment
JSNS (J-PARC Sterile Neutrino Search at J-PARC Spallation Neutron Source)
is an experiment that is searching for sterile neutrinos via the observation of
appearance oscillations using muon
decay-at-rest neutrinos. Before dedicated data taking in the first-half of
2021, we performed a commissioning run for 10 days in June 2020. Using the data
obtained in this commissioning run, in this paper, we present an estimate of
the correlated background which imitates the signal in a
sterile neutrino search. In addition, in order to demonstrate future prospects
of the JSNS experiment, possible pulse shape discrimination improvements
towards reducing cosmic ray induced fast neutron background are described.Comment: 7 pages, 3 figure
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