Isolation and Characterization of Glycerol-3-Phosphate Dehydrogenase-Defective Mutants of \u3cem\u3eNeurospora crassa\u3c/em\u3e

Three glycerol-nonutilizing mutants deficient in the mitochondrial glycerol-3-phosphate (G3P) dehydrogenase (EC 1.1.99.5) were isolated from inlts derivatives of Neurospora crassa following inositolless death at elevated temperatures on minimal glycerol medium. These mutants failed to grow on glycerol as a sole carbon source, but could grow on acetate, glucose, or mannitol media and were female fertile in genetic crosses, thereby distinguishing them from the previously reported polyol-protoperithecial defective Neurospora mutants. In addition, these glp mutants exhibited a distinct morphological alteration during vegetative growth on sucrose slants and colonial growth on sorbose-containing semicomplete medium. The glp-2 locus was assigned a location between arg-5 and nuc-2 on chromosome IIR on the basis of two-factor crosses and by duplication coverage by insertional translocation ALS176, but not NM177. All mutations were allelic as judged from the absence of both complementation in forced heterokaryons and genetic recombination among glp-2 mutations. The reversion frequency of all three mutations was less than 1010, indicating probable deletions in these strains. No G3P dehydrogenase activity could be detected in either cytosolic or mitochondrial extracts from mutant strains grown on glycerol, glucose, or galactose media. These results suggest that the glp-2 locus may be the structural gene for both the cytosolic and mitochondrial forms of G3P dehydrogenase or for a cytosolic precursor of the mitochondrial G3P dehydrogenase. The defect is specific for the G3P dehydrogenase since normal activities of the mitochondrial cytochrome oxidase and succinate dehydrogenase and the cytosolic glycerol dehydrogenase and dihydroxyacetone phosphate reductase are detected in mutant extracts. During attempted growth of glp-2 mutants on glycerol media, there was an accumulation of G3P in culture filtrates, a reduction in the mycelial growth rate, and a decreased level of glycerokinase induction

07, From Manuscripts to Printing

Devin Courtright discusses William Caxton\u27s (1415-1492) place in print history.https://pdxscholar.library.pdx.edu/textsoftime/1009/thumbnail.jp

Effects of Thyrotoxicosis on Mitochondrial Enzymes of Rat Soleus

Cytochrome oxidase, glycerol-3-phosphate dehydrogenase, and succinate dehydrogenase were measured in mitochondrial fractions obtained from rat soleus muscle of control and 8 week T3 + T4 treated animals. Under these conditions of prolonged treatment, there is a five-fold increase in the specific activities of both cytochrome oxidase and glycerols-3-phosphate dehydrogenase. Significant increases in total cellular mitochondrial content and enzyme activities were observed in T3 + T4 treated animals as compared to controls. These results indicate that thyrotoxicosis can induce selective changes in mitochondrial enzymes in slow twitch red (Type I) muscle fibers

Productivity of key informants for identifying blind children: evidence from a pilot study in Malawi.

OBJECTIVES: To determine the productivity of village-based 'key informants' (KIs) in identifying blind children. MATERIALS AND METHODS: Ngabu subdistrict (population 101,000) of Chikwawa district was divided into KI catchment areas. KIs, selected by local village leaders, were trained to register children reported to be blind or with severe visual impairment. These children were clinically assessed at designated centres. RESULTS: In total, 44 KIs were selected and trained to cover 196 villages in Ngabu. They identified and referred 151 children, 37 of whom were blind (presenting vision <3/60 best eye). Overall, village leaders tended to choose female KIs (80%) compared to male KIs (20%); however, male KIs tended to be more productive, identifying 4.22 children each (compared to 3.23 for female KIs). Male KIs were 2.7 times more likely to identify blind children compared to female KIs. Only 25% of all identified blind children of school going age were in school. CONCLUSIONS: KIs may be effective in identifying blind children in the community; however, additional work is needed to determine who will be the most effective KI in a community and whether gender roles will limit interpretation of findings from KIs activities

Effects of Mars Atmosphere on Arc Welds: Phase 2

Gas tungsten arc welding (GTAW) is a vital fusion welding process widely used throughout the aerospace industry. Its use may be critical for the repair or manufacture of systems, rockets, or facilities on the Martian surface. Aluminum alloy AA2219-T87 and titanium alloy Ti-6Al-4V butt welds have been investigated for weldability and weld properties in a simulated Martian gas environment. The resulting simulated Martian welds were compared to welds made in a terrestrial atmosphere, all of which used argon shielding gas. It was found that GTAW is a process that may be used in a Martian gas environment, not accounting for pressure and gravitational effects, as long as adequate argon shielding gas is used to protect the weld metal. Simulated Martian welds exhibited higher hardness in all cases and higher tensile strength in the case of AA2219-T87. This has been attributed to the absorption of carbon into the fusion zone, causing carbide precipitates to form. These precipitates may act to pin dislocations upon tensile testing of AA2219-T87. Dissolved carbon may have also led to carburization, which may have caused the increase in hardness within the fusion zone of the welds. Based on the results of this experiment and other similar experiments, GTAW appears to be a promising process for welding in a Martian gas environment. Additional funding and experimentation is necessary to determine the effects of the low pressure and low gravity environment found on Mars on GTAW

Perspectives of National Coordinators and Partners on the Work of the Global Trachoma Mapping Project.

PURPOSE: Neglected tropical diseases (NTDs) affect people living in the poorest regions of the world and their debilitating effects perpetuate the poverty cycle. Understanding the distribution of NTDs is crucial for effective intervention delivery. In 2012, the Global Trachoma Mapping Project (GTMP) was initiated to map >1800 suspected trachoma endemic districts by March 2015. This research was carried out to better understand the implementation experience and identify lessons which might inform the GTMP and similar initiatives. METHODS: Using grounded theory methodology, semi-structured interviews were conducted with key informants from six countries with 63% of the global mapping backlog (Ethiopia, Malawi, Mozambique, Nigeria, Solomon Islands, and Yemen). Interviews were transcribed, coded, and findings separated into categories. RESULTS: Three themes were identified during the research; planning and operations, technical implementation, and governance. The project was felt to be most successful in countries where the Ministry of Health was actively engaged in setting standards, ensuring capacity building for government staff, and guiding the training, data collection, analysis, and interpretation of data. Standardized tools, training platforms, and the use of electronic data capture increased confidence in the reliability of the survey data, informed quality improvement efforts within survey implementation, and the immediate release of results empowered end-user decision-makers. Regional collaboration between endemic countries bolstered program manager competence and confidence, while reinforcing partnerships essential to the success of the GTMP. CONCLUSIONS: We depict how innovative characteristics of the GTMP, and lessons learned from its implementation, can strengthen similar initiatives to map disease prevalence and risk factors

Monitoring interval-training responses for swimming using the 3-min all-out exercise test.

International Journal of Exercise Science 9(5): 545-553, 2016. The purpose of this study was to determine whether the 3-min all-out exercise test (3MT) could be applied to create an off-season high intensity, interval training (HIIT) program to improve performance, specifically critical velocity (CV), in the sport of swimming. We tested a group of competitive female swimmers (age = 19 ± 1 yrs, height = 169 ± 7 cm, body mass = 69 ± 9 kg) to determine their swimming CV and finite energy capacity \u3eCV (D’), and created a four week (2 d∙wk-1) personalized interval training program. Participants were divided in to two groups, a 150yd interval group (n =11) and a 250yd interval group (n =6). Each group completed a series of intervals designed to deplete a given percentage of D’ at velocities exceeding CV. A 3MT following the training period was administered to assess for any changes in CV, D’, average velocity during the first 150s of the test (V150s) and total distance traveled (D). Both groups improved their CV (+0.04 m∙s-1), V150s (+0.03 m∙s-1) and D (+8.64 m) (p \u3c 0.05), however, significant interactions for D’ between groups was not observed (p \u3e 0.05). We conclude that HIIT prescriptions based on a 3MT can improve swim performance over a four-week period. Future research on the fidelity of measuring CV and D’ using a swimming 3MT is needed to help aid practitioners in interpreting true training adaptations