45 research outputs found

    Individual Myanmar Children's Experiences in Head Start Classrooms

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    BACKGROUND: Early childhood is a crucial period for children who are dual language learners (DLLs), struggling to learn the new language as well as other skills for school readiness. In contrast to comprehensive research in ECE, there are relatively few studies conducted with DLLs, and mainly for the Latino DLLs, no other language groups. Recently, Myanmar migrants are growing rapidly and make up 25% of the total migrant population in Tulsa (NBC news, 2017). Previous studies have shown that DLL children differ in various developmental outcomes because of a myriad of factors including poverty, systemic racism, and oppression. The researchers examined the classroom experiences of Myanmar children in a Head Start program by measuring their individual language use and level of engagement then, comparing them to other racial groups. METHODS: The participants included 3- and 4-year-old children (n=1,101) in a Head Start program in Northeast OK. The measure used the Child Observational Protocol, which involved 3-second sweeps which snapshots of individual childrenโ€™s behavior across a period of time in the classroom. Observers spent approximately 4 hours in the classroom on a typical morning. All children in the classroom were observed and had an average of 9 sweeps per child. The current study specifically focused on the proportion of sweeps in which a child was listening to or talking to someone else in the classroom (in any language) and the proportion of sweeps a child was observed speaking in English. Descriptive analyses were conducted using ANOVA in SPSS. RESULTS: Results indicated that children who speak Myanmar at home had fewer times observational sweeps in which they were speaking in English (15%) compared to their African American and White peers (19-20%). However, whereas Latino children were observed more frequently to be neither speaking nor listening (45% of sweeps), Myanmar children were not significantly different than their Latino peers. Instead, Myanmar children were more likely to engage in passive instruction (15%) than their African American (10%) and White (12%) peers. CONCLUSION: Our findings suggest that Myanmar children who were enrolled in a Head Start program had bit fewer opportunities to practice their language skills and are less likely to be engaged in their classroom activities. Further research is needed to see whether these outcomes are due to language proficiency, cultural aspects, or influenced by others. This information also leads to the need for further study of how teachers interact in the classroom based on the racial groups.N

    Engineering new bone tissue in vitro on highly porous poly(ฮ‘-hydroxyl acids)/hydroxyapatite composite scaffolds

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    Engineering new bone tissue with cells and a synthetic extracellular matrix (scaffolding) represents a new approach for the regeneration of mineralized tissues compared with the transplantation of bone (autografts or allografts). In the present work, highly porous poly( L -lactic acid) (PLLA) and PLLA/hydroxyapatite (HAP) composite scaffolds were prepared with a thermally induced phase separation technique. The scaffolds were seeded with osteoblastic cells and cultured in vitro . In the pure PLLA scaffolds, the osteoblasts attached primarily on the outer surface of the polymer. In contrast, the osteoblasts penetrated deep into the PLLA/HAP scaffolds and were uniformly distributed. The osteoblast survival percentage in the PLLA/HAP scaffolds was superior to that in the PLLA scaffolds. The osteoblasts proliferated in both types of the scaffolds, but the cell number was always higher in the PLLA/HAP composite scaffolds during 6 weeks of in vitro cultivation. Bone-specific markers (mRNAs encoding bone sialoprotein and osteocalcin) were expressed more abundantly in the PLLA/HAP composite scaffolds than in the PLLA scaffolds. The new tissue increased continuously in the PLLA/HAP composite scaffolds, whereas new tissue formed only near the surface of pure PLLA scaffolds. These results demonstrate that HAP imparts osteoconductivity and the highly porous PLLA/HAP composite scaffolds are superior to pure PLLA scaffolds for bone tissue engineering. ยฉ 2000 John Wiley & Sons, Inc. J Biomed Mater Res 54: 284โ€“293, 2001Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/34419/1/16_ftp.pd

    What is the level of evidence for the use of currently available technologies in facilitating the self-management of difficulties associated with ADHD in children and young people? A systematic review

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    A number of technologies to help self-manage Attention Deficit Hyperactivity Disorder (ADHD) in children and young people (YP) have been developed. This review will assess the level of evidence for the use of such technologies. The review was undertaken in accordance with the general principles recommended in the Preferred Reporting Items for Systematic Reviews and Meta-Analysis. 7545 studies were screened. Fourteen studies of technology that aim to manage difficulties associated with ADHD in children and YP were included. Primary outcome measures were measures that assessed difficulties related to ADHD. Databases searched were MEDLINE, Web of Science (Core collection), CINAHL, the Cochrane Library, ProQuest ASSIA, PsycINFO and Scopus. The methodological quality of the studies was assessed. This review highlights the potential for the use of technology in paediatric ADHD self-management. However, it also demonstrates that current research lacks robustness; using small sample sizes, non-validated outcome measures and little psychoeducation component. Future research is required to investigate the value of technology in supporting children and YP with ADHD and a focus psychoeducation is needed

    In vivo assessment of Fibroblast growth factor(FGF)-Fibronectin fusion protein coating on titanium;Histomorphometric analysis in rabbit tibia

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    ํŒŒ์ด๋ธŒ๋กœ๋„ฅํ‹ด์€ ์„ธํฌ์™ธ๊ธฐ์งˆ์— ์กด์žฌํ•˜๋Š” ๋‹น๋‹จ๋ฐฑ์งˆ๋กœ ์„ธํฌ์˜ ๋ถ€์ฐฉ, ์ด๋™, ์„ฑ์žฅ ๋ฐ ๋ถ„ํ™”์— ๊ด€์—ฌํ•˜๋ฉฐ, ์„ฌ์œ ์•„์„ธํฌ ์„ฑ์žฅ์ธ์ž๋Š” ์„ธํฌ์˜ ์ฆ์‹ ์ด๋™ ๋ฐ ๋ถ„ํ™”์— ์˜ํ–ฅ์„ ์ฃผ๋Š” ์ค‘์š”ํ•œ ์„ฑ์žฅ์ธ์ž๋กœ ์•Œ๋ ค์ ธ ์žˆ๋‹ค. ์ตœ๊ทผ ์—ฐ๊ตฌ์— ์˜ํ•˜๋ฉด, ํŒŒ์ด๋ธŒ๋กœ๋„ฅํ‹ด์€ ์กฐ๊ณจ์„ธํฌ์˜ ํƒ€์ดํƒœ๋Š„ ์ž„ํ”Œ๋ž€ํŠธ ํ‘œ๋ฉด์œผ๋กœ ์ด์ฃผ์™€ ์ฆ์‹ ๋ฐ ๊ณจ์ƒ์„ฑ์„ ์ด‰์ง„ํ•˜๋ฉฐ, ์„ฌ์œ ์•„์„ธํฌ ์„ฑ์žฅ ์ธ์ž๋Š” ํŒŒ์ด๋ธŒ๋กœ๋„ฅํ‹ด์— ์ƒ์Šน์ž‘์šฉ์„ ํ•œ๋‹ค๊ณ  ๋ณด๊ณ ๋œ ๋ฐ” ์žˆ๋‹ค. ์ด ์‹คํ—˜์˜ ๋ชฉ์ ์€ ํŒŒ์ด๋ธŒ๋กœ๋„ฅํ‹ด ๋ฐ ์„ฌ์œ ์•„์„ธํฌ ์„ฑ์žฅ์ธ์ž์˜ ๋ณตํ•ฉ ๋‹จ๋ฐฑ์งˆ์„ ์ด์šฉํ•˜์—ฌ ํƒ€์ดํƒœ๋Š„ ์ž„ํ”Œ๋ž€ํŠธ์˜ ๊ณจ ๋ฐ˜์‘์„ ์•Œ์•„๋ณด๋Š” ๊ฒƒ์ด๋‹ค. ์ฒด์ค‘ 2.5 kg ๋‚ด์™ธ์˜ ๊ฑด๊ฐ•ํ•œ 18 ๋งˆ๋ฆฌ์˜ ์›…์„ฑ๊ฐ€ํ† ๋ฅผ ์ค€๋น„ํ•˜์—ฌ ๋ฌด๊ท  ์‚ฌ์œกํ•˜์˜€๊ณ , ์ˆœ์ˆ˜ ํƒ€์ดํƒœ๋Š„์„ ์ ˆ์‚ญ๊ฐ€๊ณตํ•˜์—ฌ ์ง๊ฒฝ 3.5mm, ๊ธธ์ด 6mm ์˜ machined surface๋ฅผ ์ง€๋‹ˆ๋Š” screw type ์˜ ์ž„ํ”Œ๋ž€ํŠธ๋ฅผ ์ค€๋น„ํ•˜์˜€๋‹ค. ์‚ฌ๋žŒ์˜ ์œ ์ „์ž๋ฅผ ๊ธฐ์ดˆ๋กœ, ์œ ์ „์ž ์žฌ์กฐํ•ฉ๋ฒ•์„ ํ†ตํ•ด, ์ ์ ˆํ•œ primer๋ฅผ ์ด์šฉํ•˜์—ฌ ์–ป์€ ์„ฌ์œ ์•„์„ธํฌ ์„ฑ์žฅ์ธ์ž๋ฅผ ํŒŒ์ด๋ธŒ๋กœ๋„ฅํ‹ด III ํ˜• ๋ถ„์ ˆ์˜ 9-10 ๋ฒˆ ๋„๋ฉ”์ธ์— ๊ฒฐํ•ฉ์‹œ์ผœ ์–ป์€ ๋ณตํ•ฉ ๋‹จ๋ฐฑ์งˆ์„ ์ค€๋น„๋œ ์ž„ํ”Œ๋ž€ํŠธ์— ํ‘œ๋ฉด์ฒ˜๋ฆฌํ•˜์—ฌ ์‹คํ—˜๊ตฐ์œผ๋กœ ํ•˜์˜€๊ณ , ํ‘œ๋ฉด์ฒ˜๋ฆฌํ•˜์ง€ ์•Š์€ ์ž„ํ”Œ๋ž€ํŠธ๋ฅผ ๋Œ€์กฐ๊ตฐ์œผ๋กœ ํ•˜์—ฌ, ๊ฐ€ํ† ์˜ ์ขŒ์šฐ ๊ฒฝ๊ณจ์— ๊ฐ๊ฐ 2 ๊ฐœ์”ฉ์˜ ์ž„ํ”Œ๋ž€ํŠธ๋ฅผ ์‹๋ฆฝํ•˜์˜€๋‹ค. 4์ฃผ ํ›„, ๊ฐ€ํ† ๋ฅผ ํฌ์ƒ์‹œ์ผœ ๊ฐ ๊ฒฝ๊ณจ ๋‹น ํ•œ ๊ฐœ์˜ ์ž„ํ”Œ๋ž€ํŠธ์—์„œ ๋’คํ‹€๋ฆผ ์ œ๊ฑฐ๋ ฅ์„ ์ธก์ •ํ•˜์˜€๊ณ  ๋‚˜๋จธ์ง€ ์ž„ํ”Œ๋ž€ํŠธ ์‹๋ฆฝ ๋ถ€์œ„ ์—์„œ๋Š” ๊ฒฝ๊ณจ์„ ํฌํ•จํ•˜๋Š” ์กฐ์งํ‘œ๋ณธ์„ ์ œ์ž‘ํ•˜์˜€๋‹ค. ์กฐ์งํ‘œ๋ณธ์ƒ์—์„œ ๊ณจ์ ‘์ด‰์ด ๊ฐ€์žฅ ์ข‹์€ 3 ๊ฐœ์˜ ๋‚˜์‚ฌ์‚ฐ์˜ ๊ธธ์ด๋ฅผ ์ธก์ •ํ•˜๊ณ , ๋‚˜์‚ฌ์™€ ์ ‘์ด‰ํ•˜๋Š” ๊ณจ์˜ ๊ธธ์ด๋ฅผ ์ธก์ •ํ•˜์—ฌ ๊ณจ-์ž„ํ”Œ๋ž€ํŠธ ์ ‘์ด‰๋„๋ฅผ ๊ตฌํ•˜๊ณ , ๊ฐ™์€ ๋ถ€์œ„์—์„œ ๋‚˜์‚ฌ์‚ฐ ์‚ฌ์ด์˜ ๋ฉด์ ๊ณผ ๊ณจ์ด ์ฐจ์ง€ํ•˜๋Š” ๋ฉด์ ์„ ๋น„๊ตํ•˜์—ฌ ๊ณจ์ƒ์„ฑ๋ฅ ์„ ์–ป์—ˆ๋‹ค. ์‹คํ—˜๊ตฐ๊ณผ ๋Œ€์กฐ๊ตฐ์˜ ๊ฒฐ๊ณผ๋Š” Student t-test ๋ฅผ ์ด์šฉํ•˜์—ฌ ์‹ ๋ขฐ๋„ 95% ์ˆ˜์ค€์—์„œ ํ†ต๊ณ„ํ•™์  ์œ ์˜์„ฑ์„ ๊ฒ€์ •ํ•˜์˜€๋‹ค. ํŒŒ์ด๋ธŒ๋กœ๋„ฅํ‹ด๊ณผ ์„ฌ์œ ์•„์„ธํฌ ์„ฑ์žฅ์ธ์ž์˜ ๋ณตํ•ฉ ๋‹จ๋ฐฑ์งˆ๋กœ ํ‘œ๋ฉด์ฒ˜๋ฆฌ๋œ ์ž„ํ”Œ๋ž€ํŠธ์™€ ํ‘œ๋ฉด์ฒ˜๋ฆฌ๋ฅผ ํ•˜์ง€ ์•Š์€ ์ž„ํ”Œ๋ž€ํŠธ๋Š” ๋’คํ‹€๋ฆผ ์ œ๊ฑฐ๋ ฅ์—์„œ๋Š” ํ†ต๊ณ„์  ์œ ์˜์„ฑ์ด ๋‚˜ํƒ€๋‚˜์ง€ ์•Š์•˜์œผ๋‚˜, ๊ณจ-์ž„ํ”Œ๋ž€ํŠธ ์ ‘์ด‰๋„์™€ ๊ณจ์ƒ์„ฑ๋ฅ ์—์„œ ๋ณตํ•ฉ ๋‹จ๋ฐฑ์งˆ๋กœ ์ฒ˜๋ฆฌ๋œ ์ž„ํ”Œ๋ž€ํŠธ๊ฐ€ ํ†ต๊ณ„์ ์œผ๋กœ ์œ ์˜ํ•˜๊ฒŒ ๋†’์€ ๊ฒฐ๊ณผ๋ฅผ ๋ณด์˜€๋‹ค. ์ด์ƒ์˜ ์—ฐ๊ตฌ๊ฒฐ๊ณผ๋กœ, ์„ฌ์œ ์•„์„ธํฌ ์„ฑ์žฅ์ธ์ž์™€ ํŒŒ์ด๋ธŒ๋กœ๋„ฅํ‹ด ๋ณตํ•ฉ ๋‹จ๋ฐฑ์งˆ๋กœ ์ฒ˜๋ฆฌํ•œ ํƒ€์ดํƒœ๋Š„ ์ž„ํ”Œ๋ž€ํŠธ๊ฐ€ ์ฃผ๋ณ€ ๊ณจ ํ˜•์„ฑ์„ ์ด‰์ง„์‹œ์ผœ, ๊ณจ์œ ํ•ฉ์„ ์ฆ์ง„์‹œํ‚ด์„ ์•Œ ์ˆ˜ ์žˆ์—ˆ๋‹ค. ๋”ฐ๋ผ์„œ, ๋ณตํ•ฉ ๋‹จ๋ฐฑ์งˆ์ด ํƒ€์ดํƒœ๋Š„ ์ž„ํ”Œ๋ž€ํŠธ์˜ ์„ฑ๊ณต๋ฅ ์„ ๋†’์ด๊ธฐ ์œ„ํ•œ ํ‘œ๋ฉด๊ฐœ์งˆ ๋ฌผ์งˆ๋กœ ์ด์šฉ๋  ๊ฐ€๋Šฅ์„ฑ์„ ํ™•์ธํ•  ์ˆ˜ ์žˆ์—ˆ๋‹ค.This study was supported by the grant from Korea Science and Technology Foundation (KOSEF) through Intellrctual Biointerface Engineering Center(IBEC) of Seoul National Universit

    ์„ฌ์œ ์•„์„ธํฌ ์„ฑ์žฅ์ธ์ž์™€ ํŒŒ์ด๋ธŒ๋กœ๋„ฅํ‹ด ๋ณตํ•ฉ ๋‹จ๋ฐฑ์งˆ๋กœ ์ฒ˜๋ฆฌํ•œ ํƒ€์ดํƒœ๋Š„์˜ ์ƒ๋ฌผํ•™์  ํšจ๊ณผ: ๊ฐ€ํ† ์˜ ๊ฒฝ๊ณจ์„ ์ด์šฉํ•œ ์กฐ์ง๊ณ„์ธกํ•™์  ๋ถ„์„

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    ํŒŒ์ด๋ธŒ๋กœ๋„ฅํ‹ด์€ ์„ธํฌ์™ธ๊ธฐ์งˆ์— ์กด์žฌํ•˜๋Š” ๋‹น๋‹จ๋ฐฑ์งˆ๋กœ ์„ธํฌ์˜ ๋ถ€์ฐฉ, ์ด๋™, ์„ฑ์žฅ ๋ฐ ๋ถ„ํ™”์— ๊ด€์—ฌํ•˜๋ฉฐ, ์„ฌ์œ ์•„์„ธํฌ ์„ฑ์žฅ์ธ์ž๋Š” ์„ธํฌ์˜ ์ฆ์‹, ์ด๋™ ๋ฐ ๋ถ„ํ™”์— ์˜ํ–ฅ์„ ์ฃผ๋Š” ์ค‘์š”ํ•œ ์„ฑ์žฅ์ธ์ž๋กœ ์•Œ๋ ค์ ธ ์žˆ๋‹ค. ์ตœ๊ทผ ์—ฐ๊ตฌ์— ์˜ํ•˜๋ฉด ํŒŒ์ด๋ธŒ๋กœ๋„ฅํ‹ด์€ ์กฐ๊ณจ์„ธํฌ์˜ ํƒ€์ดํƒœ๋Š„ ์ž„ํ”Œ๋ž€ํŠธ ํ‘œ๋ฉด์œผ๋กœ ์ด์ฃผ์™€ ์ฆ์‹ ๋ฐ ๊ณจ์ƒ์„ฑ์„ ์ด‰์ง„ํ•˜๋ฉฐ, ์„ฌ์œ ์•„์„ธํฌ ์„ฑ์žฅ์ธ์ž๋Š” ํŒŒ์ด๋ธŒ๋กœ๋„ฅํ‹ด์— ์ƒ์Šน์ž‘์šฉ์„ ํ•œ๋‹ค๊ณ  ๋ณด๊ณ ๋œ ๋ฐ” ์žˆ๋‹ค. ์ด ์‹คํ—˜์˜ ๋ชฉ์ ์€ ํŒŒ์ด๋ธŒ๋กœ๋„ฅํ‹ด ๋ฐ ์„ฌ์œ ์•„์„ธํฌ ์„ฑ์žฅ์ธ์ž์˜ ๋ณตํ•ฉ ๋‹จ๋ฐฑ์งˆ์„ ์ด์šฉํ•˜์—ฌ ํƒ€์ดํƒœ๋Š„ ์ž„ํ”Œ๋ž€ํŠธ์˜ ๊ณจ ๋ฐ˜์‘์„ ์•Œ์•„๋ณด๋Š” ๊ฒƒ์ด๋‹ค. ์ฒด์ค‘ 2.5kg ๋‚ด์™ธ์˜ ๊ฑด๊ฐ•ํ•œ 18๋งˆ๋ฆฌ์˜ ์›…์„ฑ๊ฐ€ํ† ๋ฅผ ์ค€๋น„ํ•˜์—ฌ ๋ฌด๊ท  ์‚ฌ์œกํ•˜์˜€๊ณ , ์ˆœ์ˆ˜ ํƒ€์ดํƒœ๋Š„์„ ์ ˆ์‚ญ๊ฐ€๊ณตํ•˜์—ฌ ์ง๊ฒฝ 3.5mm, ๊ธธ์ด 6mm์˜ machined surface๋ฅผ ์ง€๋‹ˆ๋Š” screw type์˜ ์ž„ํ”Œ๋ž€ํŠธ๋ฅผ ์ค€๋น„ํ•˜์˜€๋‹ค. ์‚ฌ๋žŒ์˜ ์œ ์ „์ž๋ฅผ ๊ธฐ์ดˆ๋กœ, ์œ ์ „์ž ์žฌ์กฐํ•ฉ๋ฒ•์„ ํ†ตํ•ด, ์ ์ ˆํ•œ primer๋ฅผ ์ด์šฉํ•˜์—ฌ ์–ป์€ ์„ฌ์œ ์•„์„ธํฌ ์„ฑ์žฅ์ธ์ž๋ฅผ ํŒŒ์ด๋ธŒ๋กœ๋„ฅํ‹ด โ…ขํ˜• ๋ถ„์ ˆ์˜ 9-10๋ฒˆ ๋„๋ฉ”์ธ์— ๊ฒฐํ•ฉ์‹œ์ผœ ์–ป์€ ๋ณตํ•ฉ ๋‹จ๋ฐฑ์งˆ์„ ์ค€๋น„๋œ ์ž„ํ”Œ๋ž€ํŠธ์— ํ‘œ๋ฉด์ฒ˜๋ฆฌํ•˜์—ฌ ์‹คํ—˜๊ตฐ์œผ๋กœ ํ•˜์˜€๊ณ , ํ‘œ๋ฉด์ฒ˜๋ฆฌํ•˜์ง€ ์•Š์€ ์ž„ํ”Œ๋ž€ํŠธ๋ฅผ ๋Œ€์กฐ๊ตฐ์œผ๋กœ ํ•˜์—ฌ, ๊ฐ€ํ† ์˜ ์ขŒ์šฐ ๊ฒฝ๊ณจ์— ๊ฐ๊ฐ 2๊ฐœ์”ฉ์˜ ์ž„ํ”Œ๋ž€ํŠธ๋ฅผ ์‹๋ฆฝํ•˜์˜€๋‹ค.This study was supported by the grant from Korea Science and Technology Foundation(KOSEF) through Intellctual Biointerface Engineering Center(IBEC) of Seoul National University

    <i>Sargassum</i> Detection Using Machine Learning Models: A Case Study with the First 6 Months of GOCI-II Imagery

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    A record-breaking agglomeration of Sargassum was packed along the northern Jeju coast in Korea in 2021, and laborers suffered from removing them from the beach. If remote sensing can be used to detect the locations at which Sargassum accumulated in a timely and accurate manner, we could remove them before their arrival and reduce the damage caused by Sargassum. This study aims to detect Sargassum distribution on the coast of Jeju Island using the Geostationary KOMPSAT 2B (GK2B) Geostationary Ocean Color Imager-II (GOCI-II) imagery that was launched in February 2020, with measurements available since October 2020. For this, we used GOCI-II imagery during the first 6 months and machine learning models including Fine Tree, a Fine Gaussian support vector machine (SVM), and Gentle adaptive boosting (GentleBoost). We trained the models with the GOCI-II Rayleigh-corrected reflectance (RhoC) image and a ground truth map extracted from high-resolution images as input and output, respectively. Qualitative and quantitative assessments were carried out using the three machine learning models and traditional methods such as Sargassum indexes. We found that GentleBoost showed a lower false positive (6.2%) and a high F-measure level (0.82), and a more appropriate Sargassum distribution compared to other methods. The application of the machine learning model to GOCI-II images in various atmospheric conditions is therefore considered successful for mapping Sargassum extent quickly, enabling reduction of laborersโ€™ efforts to remove them

    Climate Sensitivity and Feedback of a New Coupled Model (K-ACE) to Idealized CO2 Forcing

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    Climate sensitivity and feedback processes are important for understanding Earth&rsquo;s system response to increased CO2 concentration in the atmosphere. Many modelling groups that contribute to Coupled Model Intercomparison Project phase 6 (CMIP6) have reported a larger equilibrium climate sensitivity (ECS) with their models compared to CMIP5 models. This consistent result is also found in the Korea Meteorological Administration Advanced Community Earth System model (K-ACE). Idealized climate simulation is conducted as an entry card for CMIP6 to understand Earth&rsquo;s system response in new coupled models and compared to CMIP5 models. The ECS in the K-ACE is 4.83 K, which is higher than the range (2.1&ndash;4.7 K) of CMIP5 models in sensitivity to CO2 change and higher bound (1.8&ndash;5.6 K) of CMIP6 models. The radiative feedback consists of clear-sky and cloud radiative feedback. Clear-sky feedback of K-ACE is similar to CMIP5 models whereas cloud feedback of K-ACE is more positive. The result is attributable for strong positive shortwave cloud radiative effect (CRE) feedback associated with reduced low-level cloud cover at mid latitude in both hemispheres. Despite the cancellations in strong negative long wave CRE feedback with the changes in high-level clouds in the tropics, shortwave CRE has a dominant effect in net CRE. Detailed understanding of cloud feedback and cloud properties needs further study

    Striatal formation of 6-hydroxydopamine in mice treated with pargyline, pyrogallol and methamphetamine

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    [[abstract]]Formation of 6-hydroxydopamine (6-OHDA) has been posited in the striatum following methamphetamine treatment and plays a critical role in methamphetamine-induced nigrostriatal dopaminergic toxicity. We used high performance liquid chromatography electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) to determine the formation of 6-OHDA by the treatments of methamphetamine combined with pargyline, a monoamine oxidase inhibitor, and pyrogallol, a catechol-O-methyl-transferase inhibitor, in female C57BL/6J mouse striatum. A substantial amount of 6-OHDA (9.9 +/- 0.7pg/mg wet tissue) was detected in mice treated with pargyline (100 mg/kg) and pyrogallol (25 mg/kg) in combination. Greater striatal 6-OHDA levels were observed in mice treated with combined pargyline, pyrogallol and methamphetamine (50 mg/kg) as compared to mice treated with combined pargyline and pyrogallol. However, mice treated with pargyline and pyragollol in combination followed by one and two doses of methamphetamine exhibited comparable striatal 6-OHDA levels (23.2 +/- 4.3, 27.3 +/- 1.3 pg/mg wet tissue) in our protocol. We conclude that blockade of the primary metabolic pathways of dopamine by inhibiting both monoamine oxidase and catechol-O-methyl-transferase activities is sufficient to induce 6-OHDA formation in the striatum. Acute 6-OHDA accumulation in the striatum can be potentiated by methamphetamine, a potent dopamine releaser, administration following such metabolic inhibitions
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