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21.
Female butterflies of the spicebush swallowtail, Papilio troilus, are specialists, ovipositing on plants in the family Lauraceae. Column chromatography and HPLC were used to isolate an oviposition stimulant from the leaves of one of its hosts, Sassafras albidum. The stimulant was identified as 3-trans-caffeoyl-muco-quinic acid on the basis of FAB-MS and 1H NMR spectra as compared to a compound previously isolated from another plant. It was not active alone, but it increased the oviposition activity of butterflies when combined with other stimulant(s) at a concentration of 7 ng/mm2 leaf surface area. Other caffeoylquinic acid isomers tested did not have this effect. This is the first report of a swallowtail contact oviposition stimulant from a plant in the family Lauraceae.  相似文献   
22.
Hemimysis anomala, a Ponto-Caspian littoral mysid, is an emerging Great Lakes invader that was discovered in Lakes Michigan and Ontario in 2006. Similar to the native mysid Mysis diluviana, Hemimysis exhibits a diel vertical migration pattern but generally inhabits shallower and warmer waters than M. diluviana. Because basic information on the distribution, habitat use, and biology of Hemimysis in the Great Lakes is scarce, the potential for food web disruption by Hemimysis cannot easily be predicted. Preliminary observations indicate widespread invasion of Hemimysis in Lake Ontario. In this study, we confirm the presence of Hemimysis at sites spanning the northern and southern shores of Lake Ontario and the presence of the individuals during winter months. In one horizontal tow in November 2007, over 26,000 individuals were collected with a length range of 4.4 to 9.0 mm and an average caloric density of 611 cal/g wet weight. The most effective methods for sampling Hemimysis were horizontal tows with either a zooplankton net in the water column or a benthic sled near the lake bottom. Although more quantitative data on the life history and distribution of this species is necessary, our preliminary observations support the prediction that the potential for Hemimysis to impact the nearshore food web in Lake Ontario appears high.  相似文献   
23.
The authors evaluated multiple memory processes and explored their contributions to everyday functional limitations in persons with mild cognitive impairment (MCI). Participants included individuals with amnestic MCI, nonamnestic MCI, and healthy older adults. As expected, the amnestic MCI group performed more poorly than the control and nonamnestic MCI groups on a content memory measure. Both MCI groups, however, performed more poorly than controls on the noncontent memory measures of prospective memory, temporal order memory, and source memory. Informants also reported that the MCI groups were experiencing greater difficulty than controls completing instrumental activities of daily living (IADLs). Noncontent memory measures were found to make an independent contribution to IADL performances over and above that of content memory. These findings demonstrate that impairments in memory beyond the traditionally assessed content memory are present in individuals with amnestic MCI and with nonamnestic MCI. The results further show that these noncontent memory processes, which have been linked with executive functioning, play a role in supporting IADLs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
24.
The oxidation of iron and manganese by ozone was studied in the laboratory. Model waters both with and without organic matter were used. Results showed iron to be very rapidly oxidized to an insoluble form in the absence of organic matter. However, in the presence of organic matter the iron was protected from oxidation by ozone and precipitation. The degree to which this occurred depended on the nature of the organic matter and the chemical environment at the time of mixing the iron stock and the dissolved organic matter.

Experiments with manganese allowed the determination of second order rate constants for the reaction of ozone with manganese at various pH values. The oxidation of manganese in the presence of organic matter occurred in competition with oxidation of the organic matter. As a result, high ozone doses were required to achieve the same degree of removal of manganese. An increase in bicarbonate alkalinity from 50 mg/L to 200 mg/L did not result in an acceleration of the manganese oxidation in the absence of organic matter. However, in the presence of organic matter, higher levels of bicarbonate created conditions that resulted in more complete oxidation of the manganese following total consumption of the dosed ozone.  相似文献   

25.
Currently, energy performance indicators for buildings are associated with the primary energy source consumption, CO2 emissions or net energy distribution, which together set the building’s energy efficiency. The evaluation is frequently based on setpoint temperatures and hours of operation. However, these fixed parameters are not suitable for social housing simulation as their performance tends to be in free running, excluding extremely cold or warm conditions. Therefore, a more successful assessment for the efficiency of these buildings is the users’ capability to live within adaptive comfort ranges without air conditioning systems. The aim of this research is to analyze new Chilean standards for sustainable social housing in the context of climate change using the adaptive comfort approach addressed in EN 15251:2007. Using EnergyPlus simulation software, 16 parametric series are analyzed for current conditions and validated against on-site measurements. Meanwhile, a prediction for the climate in 2050 has also been taken into account. The case study is the most widespread low cost dwelling model. The study demonstrates that the period of time within thermal comfort conditions varies substantially if analysis is done using the adaptive comfort standard or the Sustainable Construction Code (CCS) for Chilean housing. Considering climate change, the percentage of time fluctuates from ?19.00% to 24.30%. Concluding that the adaptive comfort model has a greater capacity to positively assess indoor temperatures for social housing in Central-Southern Chile. This research also establishes that it is possible to provide homes where standards are improved within comfort conditions without using artificial means, 99.67% of the time currently and 88.89% in the future.  相似文献   
26.
The purpose of the present study was to investigate the effects of gamma linolenic acid (GLA) on cardiovascular responses to psychosocial stress (isolation) and to pressor hormones in the genetically borderline hypertensive rat (SHR×WKY). Adult male SHR×WKY were divided into two groups following five weeks of group housing. One group (GLA) received eight weeks constant flow osmotic pumps releasing 0.04 mg GLA in olive oil/kg-hr, while the second group received dummy pumps (DUM). One week following pump implantation, each group was divided into two subgroups and exposed to a four-week experimental period of either continued group housing (no stress) or isolation (stress). A two-week recovery period of group housing followed the experimental period. Blood pressure and heart rate were determined weekly by the tail cuff technique. At the end of the recovery period, animals in the no stress condition were anesthetized and received an arterial cannula for NOR and ANG infusion and direct BP recording. Then the responses to an ED50 of NOR and ANG were determined. All animals were then killed for determination of heart weight and adrenal weight. All groups had mean control period systolic BP values ranging from 143–146 mm Hg. In the no stress condition, neither GLA nor DUM altered BP over the course of the study. However, BP increased in the DUM group durign all four weeks of the isolation period vs the control period (p<0.01), whereas BP increased only in week 1 in the GLA group (p<0.05). Heart rate increased during stress in the DUM group (p<0.05), but not in the GLA group. Vascular reactivity to NOR was unaffected by GLA administration. In contrast, GLA increased the duration of the pressor response to ANG (p<0.01), but tended to decrease the magnitude of the pressor response (p<0.09) vs DUM. GLA had no effect on heart weight/body weight ratio. Adrenal weight/body weight ratio was lower in the DUM/no stress group than all other treatment groups. These data indicate that GLA administration attenuates the cardiovascular responses to chronic stress in animals with a genetic predisposition to hypertension, in the absence of an effect on resting BP. They also demonstrate a limitation of GLA effect, in mature animals, to epigenetic pressor factors. Furthermore, GLA action may involve an alteration of the cardiovascular responses to ANG, but not NOR. These findings suggest that GLA may be useful in preventing the neurogenic triggering of hypertension by chronic stress in genetically stress-sensitive animals.  相似文献   
27.
Discusses the inadequacy of old, and the lack of new guidelines for the protection of the rights of individuals in psychological treatment. A questionnaire containing vignettes of clinical and research situations that required decision-making processes was completed by 113 members of the Division of Clinical Psychology of the American Psychological Association. Data suggest that there is inconsistency in decision making. Suggestions for improving the decision-making process and enhancing consistency are presented. (8 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
28.
Massive quantities of hazardous substances are transported each day throughout the United States. While most arrive safely at their destination, uncontrolled releases of substances in transit do occur and have the potential of causing acute public health consequences for those individuals at or near the release. Data from 16 state health departments participating in the Agency for Toxic Substances and Disease Registry's (ATSDR) Hazardous Substances Emergency Events Surveillance (HSEES) system were analyzed to determine the public health consequences that occurred from actual releases in transit. Of the 9392 transportation events analyzed, 9.1% resulted in 2008 victims, including 115 deaths. The population groups injured most often were employees and the general public. The most common injury sustained was respiratory irritation. Evacuations were ordered in 5.5% of events effecting at least 63,686 people. Human error and equipment failure were the most common factors leading to events. These findings underscore the importance of job safety training, community planning, and effective emergency response to prevent adverse public health consequences from occurring or lessen their effect on the public.  相似文献   
29.
Jie MS  Lau MM 《Lipids》2000,35(10):1135-1145
Primary amines (ammonia, methyl, propyl, octyl, octadecyl, phenyl, benzyl, phenethyl) including methyl esters of amino acids (glycine, dl-alanine, l-valine, l-leucine, L-tyrosine, and l-methionine), and secondary amines (dimethyl, diethyl, dipropyl, diisopropyl, dioctyl, and diphenyl) attack regiospecifically the central carbon atom of the allene system of methyl 12-keto-9,10-octadecadienoate (1) to give the corresponding lipidic enaminone derivatives (2–21) with an average yield of 77%. The E- and Z-configuration of the enaminone system of these novel lipid derivatives was confirmed by infrared and nuclear magnetic resonance spectroscopic techniques. Primary amines furnished Z-enaminones, while secondary amines gave E-enaminones.  相似文献   
30.
Current antiplatelet drugs for the treatment of arterial thrombosis often coincide with increased bleeding risk. Several tyrosine kinase inhibitors (TKIs) for cancer treatment inhibit platelet function, with minor reported bleeding symptoms. The aim of this study was to compare the antiplatelet properties of eight TKIs to explore their possible repurposing as antiplatelet drugs. Samples of whole blood, platelet-rich plasma (PRP), or isolated platelets from healthy donors were treated with TKI or the vehicle. Measurements of platelet aggregation, activation, intracellular calcium mobilization, and whole-blood thrombus formation under flow were performed. Dasatinib and sunitinib dose-dependently reduced collagen-induced aggregation in PRP and washed platelets; pazopanib, cabozantinib, and vatalanib inhibited this response in washed platelets only; and fostamatinib, axitinib, and lapatinib showed no/limited effects. Fostamatinib reduced thrombus formation by approximately 50% on collagen and other substrates. Pazopanib, sunitinib, dasatinib, axitinib, and vatalanib mildly reduced thrombus formation on collagen by 10–50%. Intracellular calcium responses in isolated platelets were inhibited by dasatinib (>90%), fostamatinib (57%), sunitinib (77%), and pazopanib (82%). Upon glycoprotein-VI receptor stimulation, fostamatinib, cabozantinib, and vatalanib decreased highly activated platelet populations by approximately 15%, while increasing resting populations by 39%. In conclusion, the TKIs with the highest affinities for platelet-expressed molecular targets most strongly inhibited platelet functions. Dasatinib, fostamatinib, sunitinib, and pazopanib interfered in early collagen receptor-induced molecular-signaling compared with cabozantinib and vatalanib. Fostamatinib, sunitinib, pazopanib, and vatalanib may be promising for future evaluation as antiplatelet drugs.  相似文献   
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