Comparing annual MODIS and PRODES forest cover change data for advancing monitoring of Brazilian forest cover

Annual forest cover loss indicator maps for the humid tropics from 2000 to 2005 derived from time-series 500 m data from the MODerate Resolution Imaging Spectroradiometer (MODIS) were compared with annual deforestation data from the PRODES (Amazon Deforestation Monitoring Project) data set produced by the Brazilian National Institute for Space Research (INPE). The annual PRODES data were used to calibrate the MODIS annual change indicator data in estimating forest loss for Brazil. Results indicate that MODIS data may be useful in providing a first estimate of national forest cover change on an annual basis for Brazil. When directly compared with PRODES change at the MODIS grid scale for all years of the analysis, MODIS change indicator maps accounted for 75% of the PRODES change. This ratio was used to scale the MODIS change indicators to the PRODES area estimates. A sliding threshold of percent PRODES forest and 2000 to 2005 deforestation classes per MODIS grid cell was used to match the scaled MODIS to the official PRODES change estimates, and then to differentiate MODIS change within various sub-areas of the PRODES analysis. Results indicate significant change outside of the PRODES-defined intact forest class. Total scaled MODIS change area within the PRODES historical deforestation and forest area of study is 120% of the official PRODES estimate. Results emphasize the importance of synoptic monitoring of all forest change dynamics, including the cover dynamics of intact humid forest, regrowth, plantations, and cerrado tree cover assemblages. Results also indicate that operational MODIS-only forest cover loss algorithms may be useful in providing near-real time areal estimates of annual change within the Amazon Basin.     

49—2游泳池反应堆几种假想事故分析

文章把热工水力计算程序RETRAN-02应用到游泳池反应堆瞬态事故分析上,并对假想的部分失流事故、失电事故和控制棒失控事故进行了计算与讨论,这些结果对反应堆运行安全是有参考价值的。     

Multiple centrosomal microtubule organising centres and increased microtubule stability are early features of VP-16-induced apoptosis in CCRF-CEM cells

Microtubular reorganisation contributing to apoptotic morphology occurs in normal and neoplastic cells undergoing apoptosis induced by cytotoxic drugs [1-3]. The aim of this study was to correlate the changes in the microtubules (MTs) with behavior of the centrosome in apoptotic cells, and to see whether post-translational changes in tubulin occurred with the emergence of apoptotic MT bands. Apoptosis was induced in the human T-cell leukaemia line (CCRF-CEM) by treatment with 17 microM etoposide over a 4 h period. The time course of changes was assessed using flow cytometry (FCM) and immunocytochemistry in cells labelled for a centrosomal antigen (CSP-alpha) or alpha-tubulins. One hour following treatment we observed multiple centrosomal microtubule organising centres (MTOCs) associated with the nucleus and the transient appearance of a subset of stable MTs detected with an antibody specific for acetylated alpha-tubulin, as the bands of MTs which lobulate the nucleus are formed. The altered properties of the MTs thus reflect changes in function as apoptosis progresses.     

Wide-line NMR spectra of some saturated and unsaturated long chain fatty acids

Wide-line NMR spectra were obtained on a series of homologous normal long chain fatty acids: decanoic, lauric, myristic, palmitic, stearic and behenic as well as three isostructural unsaturated acids: elaidic,trans-5-eicosenoic and brassidic. Also included are NMR spectra of metastable forms of both the saturated and unsaturated acids. NMR parameters are correlated with carbon chain length, crystal long spacing and density. Polymorphic forms are distinguished on the basis of line width and second moment differences. Presented in part at the Meeting of the Society for Applied Spectroscopy, October, 1970, New Orleans, La. So. Market. Nutr. Res. Div., ARS, USDA.     

Fatty acid polymorph identification by infrared

IR spectra in the 7.5–25.0 μm region are shown to be unique for polymorphic modifications of long chain saturated fatty acids of even carbon number and also for the individual fatty acids. IR spectra are presented for the A-, B-, C- and E-forms of stearic acid and for the C-form of myristic, palmitic, arachidic and behenic acid and the differences discussed. X-ray determined crystal long spacings for the A-, B-, C- and E-forms of a series of homologous even carbon-numbered acids are presented and compared with literature values. The formation of the different polymorphic forms are found to be temperature-concentration related and affected little by polarity of the solvent. Wideline nuclear magnetic resonance second moment values are given for the polymorphic forms of stearic acid. Presented in part at the AOCS Meeting, Houston, May 1971. S. Market. Nutr. Res. Div., ARS, USDA.     

The new temperance movement in the United States: what happened to macrostructural factors in alcohol problems?

BACKGROUND: Pulmonary tuberculosis can produce unusual radiographic appearances and negative results of sputum and bronchoscopic examinations are common. This study assessed the value of ultrasound guided aspiration biopsy in the diagnosis of pulmonary tuberculosis with unusual radiographic appearances. METHODS: Thirteen patients, ultimately diagnosed as having tuberculosis, underwent a chest ultrasonographic examination between June 1984 and August 1991. All had sputum available for examination and nine were also examined by bronchoscopy. Ten patients who had a negative sputum smear and negative bronchoscopic brushing smears underwent ultrasound guided aspiration or biopsy. Percutaneous aspiration was performed with a 22 gauge needle. If the smear did not reveal acid fast bacilli, a biopsy sample was taken with a 16 gauge Tru-cut needle to obtain a histological diagnosis. RESULTS: The ultrasonographic examination delineated the more complex nature of the lesions better than the chest radiograph. Ultrasound guided aspiration biopsy provided the diagnosis in nine of 10 patients, while the sputum smear and culture provided diagnosis in five of 13, and bronchoscopy in four of nine. In terms of rapid diagnosis, ultrasound guided aspiration biopsy gave the diagnosis in eight of 10 cases. No patient developed a major complication. CONCLUSION: Ultrasonography can direct the needle to the most suitable part of a lesion to obtain the relevant specimens. The diagnostic yield is high and the procedure is relatively safe. It is especially helpful in patients with negative results of sputum and bronchoscopic examinations.     

Deferoxamine in thalassemia major

The evolution of women's health both in the United States and abroad is a direct result of an intense commitment to scientific investigation and education. Society serves to benefit greatly from this global effort.     

Methods for the determination of cyclopropenoid fatty acids V. A spectrophotometric method for cottonseed oils based upon the Halphen-test reaction

A spectrophotometric method of analysis for the quantitative estimation of cyclopropenoid fatty acids in cottonseed oil based upon the Halphen-test reaction has been described. Various parameters involved in the reaction have been investigated and two pigment fractions responsible for the characteristic Halphen-test cherry-red color have been isolated. The method is applicable to relatively small amts of sample material. The average deviation from the actual cyclopropenoid acid contents as determined by the stepwise HBr titration method was less than ±0.02% in both the refined and crude oil series. S. Utiliz. Res. Dev. Div., ARS, USDA.     

Adhesion and surface analysis of carbon fibres electrochemically oxidized in aqueous potassium nitrate

Type II carbon fibres (PAN-based) have been electrochemically oxidized in aqueous potassium nitrate to varying electron charge densities (0–4294 Cg-1). The fibres were subsequently characterized by angle-resolved X-ray photoelectron spectroscopy (ARXPS) and ion scattering spectroscopy (ISS) and the results were correlated to acid/base surface titrations and BET surface area measurements. Relative to the as-received fibres (commercially treated, but unsized), the electrochemical treatments increased the ARXPS O/C atomic ratios by approximately 50%–100% and the concentration of oxidized carbon became more uniform within the XPS sampling depth (10 nm). At the same time, the number of acidic functions titrated by sodium hydroxide rose from about 2.6 eq g-1 to 1078 eq g-1, and the BET surface area increased from 0.67 m2 g-1 to 2.9 m2 g-1. A large portion of the increase in acidic groups was due to the increased fibre oxidation below the XPS sampling depth. The surface densities of acidic functions (functions/nm2) determined from NaOH uptake and nitrogen BET surface area experiments were far larger than is physically possible. Thus, it is postulated that aqueous NaOH solutions are able to access a much larger surface region than can be measured by nitrogen BET. A model involving subsurface pores, voids, crevasses, etc., which become available via swelling during solvation in aqueous NaOH, but are at least partially closed off when dry (during BET measurements), was proposed. The quantity of acidic functions introduced (detected by NaOH) was directly proportional to the extent of oxidation as referenced to the electron charge density (C g-1). The ISS spectra suggest that the surface density of carbon/oxygen groups was also increased. Single-fibre fragmentation tests (using an epoxy resin matrix) revealed that in most cases the interfacial shear strengths (IFSS) increased with increasing ARXPS O/C atomic ratio probably due to enhanced fibre/matrix chemical bonding and/or mechanical interlocking. As the extent of the electrochemical oxidation progressed above 1500 C g-1 the IFSS of single filament specimens then began to decrease. This was due to a continuing decrease in filament tensile strength as the extent of electro-oxidation increased. The critical transfer length, Lc, also decreased from 0.36 mm to 0.18 mm as the extent of electro-oxidation proceeded. Electrochemically oxidized fibres were compared to nitric acid-oxidized fibres in terms of acidic groups generated, BET surface areas, acidic group surface densities, dye adsorption with methylene blue and the role of aqueous NaOH in exposing some of the microstructure created by oxidative processes. © 1998 Kluwer Academic Publishers