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Transportation is one of the key sectors causing greenhouse gas (GHG) emissions and air pollution. With the substantial increase in passenger and freight transportation, the corresponding GHG emissions and air pollutants are expected to increase significantly. Recent global and national policies are targeting at reducing environmental impacts of transportation activities. The promotion of public transportation and development of electric buses (e-buses) will reduce the use of fossil fuels in transportation, and consequently, reduce GHG emissions. This study assesses the life cycle GHG emissions and other environmental impacts of e-bus, and compares them with those of conventional bus operated in Vietnam. The results indicate that e-bus is a preferred choice in most of studied environmental impact categories over the whole life cycle such as GHG emission, ozone depletion, ozone formation, fine particulate matter formation, acidification, etc. For GHG emissions, the adoption of electric mobility will reduce 42.62 gCO(2)eq per passenger km of carbon footprint if conventional buses are substituted by e-buses in Vietnam.

BackgroundLittle is known about the natural growth characteristics of untreated glioblastoma before surgical or therapeutic intervention, because patients are rapidly treated after preliminary radiographic diagnosis. Understanding the growth characteristics of uninhibited human glioblastoma may be useful for characterizing changes in response to therapy. Thus, the objective of the current study was to explore tumor growth dynamics in a cohort of patients with untreated glioblastoma before surgical or therapeutic intervention.MethodsNinety-five patients with glioblastoma who had measurable enhancing disease on >2 magnetic resonance imaging scans before surgery were identified. Tumor growth rates were quantified in 4 different ways (the percentage change per day, the absolute rate of change per day, the estimated volumetric doubling time, and the radial expansion rate) using 3 different approaches (bidirectional product, enhancing disease, and total lesion volume).ResultsThe median volumetric doubling time was 21.1 days, the percentage change in tumor volume was 2.1% per day, and the rate of change in total lesion volume was 0.18 cc per day. The length of follow-up between magnetic resonance imaging examinations should be >28 days to detect progressive disease with high specificity. Small initial tumor sizes (

Location, size and histological appearance of colorectal neoplasms were examined retrospectively. A total of 1,357 polyps (including small ones, diameter below 0.5 cm) were found in 1,022 of 3,057 coloscopies. The coloscopies were indicated by findings on preceding radiological or endoscopic examinations (48%), occult blood in stool (18%), during follow-up after polypectomy (21%), and after colorectal carcinoma (13%). A single polyp was found in 718 cases (70%), two to four in 221 (26%), more than five in 33 (4%), 1,106 polyps (61%) were found on high coloscopy; 380 of these (38%) were located proximal to the left flexure. Among the 1,230 polyps examined histologically 907 (74%) were adenomas (494 tubular [54%], 379 tubulovillous [42%], 34 villous [4%]). 251 (28%) of the adenomatous polyps and 49 (32%) of the 151 carcinomas were located proximal to the left flexure. The incidence of moderately severe to severe dysplasias increased with increasing diameter of the polyps: 55% of those smaller than 0.5 cm were adenomas. 70% of polyps with a diameter over 1.0 cm were tubulovillous or villous adenomas. The findings confirm that there is a high incidence of polyps proximal to the left flexure. A complete coloscopy should therefore be done as a matter of course.

The study (a) assesses the life cycle energy consumption and air emissions impacts of battery electric buses (e-buses) and conventional buses operated in Vietnam, and (b) compares them with those of hydrogen buses. The results indicate that e-buses and hydrogen buses are preferred options compared to conventional buses in terms of energy consumption, GHG emissions and other air quality impacts over their whole life cycle. Life cycle energy consumption of diesel buses is triple that of e-buses, and is significantly higher than that of hydrogen buses. Replacing conventional buses with e-buses can reduce energy consumption by 50%. For GHG emissions and air quality impacts, the adoption of electric and hydrogen mobility in replacement of conventional buses will reduce GHG emissions by 39%, and other impacts related to air quality by 13% to 90%.