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101.
102.
In 1941, the Baltimore City Council passed a law, the Ordinance on the Hygiene of Housing, declaring that all property in the city should be ‘maintained in good repair by the owner or agent, and fit for human habitation’. The campaign of housing-code enforcement that followed, known as the Baltimore Plan, made the city famous. When historians write about American housing-reform efforts during the mid-20th century, they tend to focus on big-ticket federal policies; by contrast, the Baltimore Plan seems too small to be significant. But it is more than a curiosity. First in Baltimore and then across the country, the neat cause-and-effect it posited between good stewardship and good housing crowded out more challenging ways of thinking about the problem. Eventually, the Baltimore Plan turned into a policy tool that reinforced the interests of the real estate industry at the expense of poor people. In that regard, the Baltimore Plan laid the foundations for federal disinvestment in the provision of decent housing and the midcentury tragedy of urban renewal.  相似文献   
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104.
In offspring exposed in utero to a maternal diet high in fat (HF), we have previously demonstrated that despite similar birth weights, HF adult offspring at 6 months of age had significantly higher body weights, greater adiposity, and increased triacylglycerol (TAG) levels as compared to controls. We hypothesized that a maternal HF diet predisposes to offspring adiposity via a programmed increase in the synthesis of monounsaturated fatty acids in the liver and hence increased substrate availability for liver TAG synthesis. We further hypothesized that programmed changes in offspring liver fatty acid metabolism are associated with increased liver expression of the lipogenic enzyme stearoyl‐CoA desaturase‐1 (SCD‐1). Female rats were maintained on a HF diet rich in monounsaturated fatty acids (MUFA) prior to and throughout pregnancy and lactation. After birth, newborns were nursed by the same dam, and all offspring were weaned to control diet. Plasma and liver fatty acid compositions were determined using gas chromatography/mass spectrometry. Fatty acid C16 desaturation indices of palmitoleic/palmitic and (vaccenic + palmitoleic)/palmitic and the C18 desaturation index of oleic/stearic were calculated. Liver protein abundance of SCD‐1 was analyzed in newborns and adult offspring. Plasma and liver C16 desaturation indices were decreased in HF newborns, but increased in the adult offspring. Liver SCD‐1 expression was increased in the HF adult offspring. These data show that the maternal HF diet during pregnancy and lactation increases offspring liver SCD‐1 protein abundance and alters the liver C16 desaturase pathway.  相似文献   
105.
Planners, designers, environmentalists, concerned citizens, and government officials are interested in the management and preservation of small rare and unique ecological environments. Scholars have discovered that land-use and visual quality metrics often co-vary together and that various land-uses reside on a continuum scale from high respondent preference (biospheric land-uses) to low respondent preference (noospheric land-uses). This study assessed and documented the visual metrics for the Maxton Plains alvar/alvar grassland plant communities found on Drummond Island, Michigan, USA. These unique, small, and rare landscape types are not usually studied by large-scale visual quality mapping efforts which assess urban areas, woodlands, water, farmland, pastureland, and prairies. The visual metrics were assessed using two versions of predictive visual quality assessment models. Results from 60 field photographs reveal that the visual metrics assessment for the Maxton Plains alvars/alvar grasslands have a moderate visual preference, consistent visual quality scores: ranging from the low to middle 50s with the first equation and high 40s to low 50s with the second equation. Compared to many landscape and land-uses, these environments have scores that indicate a moderate visual preference and appreciation. Scores beyond±2.5 of the mean would indicate a significant (p≤0.05) perceivable drift from the existing conditions. The visual metrics provide a numerical framework for managing the spatial contents within and adjacent to the alvars. Landscape features such as buildings, invasive woodlands, agriculture, and pavement would all decrease the visual quality beyond the ± 2.5 score range.  相似文献   
106.
示波器是大多数电子工程师进行试验、信号评估、故障测试和规格检查过程中必不可少的设备。即使是在经济不景气的情况下,示波器市场也始终呈现出不断创新的态势。甚至可以说,这一创新趋势也正因为大环境的萧条显现的愈发明显。  相似文献   
107.
108.
This study used molecular methods to measure concentrations of four enteric viruses (adenovirus, enterovirus, norovirus GI, and norovirus GII) and fecal source tracking markers (human, ruminant, and pig Bacteroidales) in land-based runoff from 22 tropical streams on O'ahu, Hawai'i. Each stream was sampled twice in the morning and afternoon during dry weather. Viruses and human Bacteroidales were widespread in the streams. Watershed septic tank densities were positively associated with higher occurrence of human Bacteroidales and norovirus. There were no associations between occurrence of viruses and fecal indicator concentrations. Virus concentrations and previously reported culturable Salmonella and Campylobacter were used as inputs to a quantitative microbial risk assessment (QMRA) model to estimate the risk of acquiring gastrointestinal (GI) illness from swimming in tropical marine waters adjacent to discharging streams. Monte Carlo methods were used to incorporate uncertainties in the dilution of stream discharge with seawater, swimmer ingestion volumes, pathogen concentrations, and dose-response parameters into the model. Median GI illness risk to swimmers from exposure to coastal waters adjacent to the 22 streams ranged from 0 to 21/1000. GI illness risks from viral exposures were generally orders of magnitude greater than bacterial exposures. Swimming adjacent to streams positive for norovirus or adenovirus resulted in the highest risks. The median risk adjacent to each stream was positively, significantly correlated to the concentration of Clostridium perfringens in the stream. Although a number of important assumptions were made to complete the QMRA, results suggest land-based runoff in the tropics as a potential source of GI illness risk, with pathogens coming from both human and nonhuman nonpoint sources including septic tanks.  相似文献   
109.
The performance of the technique of diffusive gradients in thin films (DGT) was characterized in well-defined systems containing cadmium with chloride and nitrate ions, simple organic ligands (nitrilotriacetic acid and diglycolic acid), and Suwannee river fulvic acid for the pH range 5-8. Cd was fully labile in all Cd, Cl-, and NO3- solutions tested (I= 0.1 and 0.01 M), even atvery low Cd concentrations (10 nM), consistent with there being no binding of Cd to the diffusive gel. Diffusion coefficients of Cd-nitritotriacetic acid (NTA) and Cd-diglycolic acid (DGA) species were measured and found to be ca. 25-30% lower than the equivalent coefficient for free metal ions. These values were used to calculate concentrations of labile Cd from DGT measurements in solutions of Cd with NTA or DGA. Cd-NTA and Cd-DGA species were found to be fully DGT-labile. DGT devices that used a diffusive gel with a reduced pore size, which retarded the passage of fulvic acid species through the gel, were used to estimate the proportion of Cd complexed by fulvic acid. These results were compared with predictions of the solution speciation from models with default parameter values. ECOSAT, incorporating the NICA-Donnan model, correctly predicted the magnitude of the binding and its pH dependence, while predictions from WHAM V (with humic ion binding model V) and WHAM 6 (with humic ion binding model VI) were less satisfactory at predicting the pH dependence. Reasonable fits to the data could be obtained from WHAM 6 when the effective binding constant log K(MA) was changed from 1.6 to 1.5, the value of deltaLK1 from 2.8 to 1.0 to minimize the dependence on pH, and the value of deltaLK2 from 1.48 to 1.0 to decrease the strength of the strong bidentate and tridentate binding sites.  相似文献   
110.
Personality traits related to neuroticism and disinhibition have been consistently associated with substance use disorders (SUDs). It is unclear, however, whether different personality traits predict distinct forms of substance dependence. Additionally, it is unclear whether personality traits continue to predict alcohol, drug, and tobacco dependence after controlling for comorbid antisociality and other SUDs. The current study addresses these questions by characterizing relations between personality traits and substance dependence symptoms in a longitudinal sample of 3,720 college students. Results revealed that antisociality and certain core personality traits predicted multiple types of substance pathology. In addition, several personality traits were differentially associated with alcohol, drug, and tobacco symptomatology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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