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121.
Cunningham CE Bruce BS Snowdon AW Chen Y Kolga C Piotrowski C Warda L Correale H Clark E Barwick M 《Accident; analysis and prevention》2011,43(6):1999-2009
Automobile crashes are the leading cause of death in children aged 1–14 years. Many children, however, are not properly restrained in safety seats that reduce serious injury and death. This study used a discrete choice conjoint experiment to study factors influencing the decision to use booster seats. Parents of 1714 children aged 4–9 years from nine Canadian provinces completed choice tasks presenting experimentally varied combinations of 15 4-level booster seat promotion attributes. Latent class analysis yielded three segments of parents. The choices of the Benefit Sensitive segment (50%) were most sensitive to the injury prevention benefits of booster seats. The choices of parents in the Context Sensitive segment (33.5%) were more likely to be influenced by installation complexity, oppositional behavior, and the prospect that their child may be teased for riding in booster seats. Parents in the High Risk segment (16.5%) were younger, less educated, and less knowledgeable about vehicle safety legislation. They anticipated fewer benefits, expected more barriers and were less likely to use booster seats. Simulations suggest that consistent enforcement coupled with advertising focusing on injury prevention and the use of booster seats by other parents would increase adoption. 相似文献
122.
Aerosol particles, especially those ranging from 50 to 200 nm, strongly impact climate by serving as nuclei upon which water condenses and cloud droplets form. However, the small number of analytical methods capable of measuring the composition of particles in this size range, particularly at the individual particle level, has limited our knowledge of cloud condensation nuclei (CCN) composition and hence our understanding of aerosols effect on climate. To obtain more insight into particles in this size range, we developed a method which couples a growth tube (GT) to an ultrafine aerosol time-of-flight mass spectrometer (UF-ATOFMS), a combination that allows in situ measurements of the composition of individual particles as small as 38 nm. The growth tube uses water to grow particles to larger sizes so they can be optically detected by the UF-ATOFMS, extending the size range to below 100 nm with no discernible changes in particle composition. To gain further insight into the temporal variability of aerosol chemistry and sources, the GT-UF-ATOFMS was used for online continuous measurements over a period of 3 days. 相似文献
123.
D. Thuau M. Abbas S. Chambon P. Tardy G. Wantz P. Poulin L. Hirsch I. Dufour C. Ayela 《Organic Electronics》2014,15(11):3096-3100
We report a low-cost piezoresistive nanocomposite based organic micro electro mechanical system (MEMS) strain sensor that has been combined to an organic field effect transistor (OFET) with the objective of amplifying the sensitivity of the sensor. When the MEMS cantilever is strained by a mechanical deflection, the resulting variation of resistivity influences the gate voltage (VGS) of the OFET and, hence, changes the drain current (IDS) of the transistor. The present combination allows an enhancement of sensitivity to strain by a factor 3.7, compared to the direct detection of resistance changes of the nanocomposite. As a consequence, a low limit of detection of 24 ppm has been estimated in terms of strain transduction efficiency. Furthermore, the organic microsystem exhibits a short response time and operates reversibly with an excellent robustness. 相似文献
124.
Melanie Kaiser Maria Donatella Semeraro Markus Herrmann Gudrun Absenger Armin Gerger Wilfried Renner 《International journal of molecular sciences》2021,22(13)
Immune functions decline as we age, while the incidence of cancer rises. The advent of immune checkpoint blockade (ICB) has not only revolutionized cancer therapy, but also spawned great interest in identifying predictive biomarkers, since only one third of patients show treatment response. The aging process extensively affects the adaptive immune system and thus T cells, which are the main target of ICB. In this review, we address age-related changes regarding the adaptive immune system with a focus on T cells and their implication on carcinogenesis and ICB. Differences between senescence, exhaustion, and anergy are defined and current knowledge, treatment strategies, and studies exploring T cell aging as a biomarker for ICB are discussed. Finally, novel approaches to improve immunotherapies and to identify biomarkers of response to ICB are presented and their potential is assessed in a comparative analysis. 相似文献
125.
In 2 populations of fruit fly, bidirectional selection and single-pair matings for high and low expression of central excitatory state (CES) in 4 experiments succeeded in producing from one a high, but not a low, CES line, and from the other a low, but not a high, CES line. Compared with results from the selection studies of the blow fly, Phormia regina, in which 1 major gene correlate of CES has been found, the present results suggest that in D. melanogaster there are several gene correlates of CES, opposite alleles of some of which have become fixed in the divergent lines. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
126.
We investigated the expression pattern of the endothelin-A receptor and endothelin 1 genes, the mutations of which affect the development of the mesectodermal derivatives of the neural crest. We show here that endothelin 1 is expressed by the environment of the cephalic neural crest cells invading branchial arches. Later on, while the neural crest-derived tissues of the head continue to express endothelin-A receptor, endothelin 1 is no longer expressed in their environment. 相似文献
127.
Dörte Schumacher Daniela Hirsch Bettina Cämmerer Lothar W. Kroh 《European Food Research and Technology》1996,203(4):385-390
The enzymatic degradation of thermal treated α-glucans with amylolytic enzymes depends on the reaction environment (T, pH, moisture), the degree of polymerisation (DP) and the branch of the substrates as well as on the presence of amino compounds. The chemical changes of the α-glucans due to thermolysis at 180 °C are characterized by means of the amount of reducing substances and the amount of maltooligosaccharides (HPLC). In general the enzymatic degradability of the thermal treated α-glucans is decreased with increasing time of thermolysis, temperature and moisture content. The enzyme activity with the thermal treated α-glucans is diminished in the same way. The addition of amino compounds reduces the enzymatic degradability only at the beginning of the reaction. With increasing time of thermolysis the thermolysates without glycine addition are hardly degradated. As reason for these differences in the enzymatic degradation transglycosylation and non-enzymatic browning reactions (caramalisation/ Maillard-reaction) are assumed. 相似文献
128.
129.
STUDY OBJECTIVE: To estimate the financial costs incurred by outpatient surgical centers in managing postoperative nausea and vomiting (PONV). DESIGN: Prospective, observational study. SETTING: 6 hospital-based outpatient surgery centers. PATIENTS: 211 adult patients undergoing outpatient surgery for laparoscopy, dilatation and curettage, knee arthroscopy, or hernia repair. MEASUREMENTS AND MAIN RESULTS: Of the 211 patients studied, 34 experienced PONV in the recovery room. For those patients experiencing PONV, personnel, supply, and drug costs for management of this condition averaged $14.94 per patient. In addition, PONV increased the centers' operating costs by delaying patient discharge by an average of 24 minutes. A minimum estimate of this cost, based on nurses' wage rates, was $7.12. This estimate is appropriate only for short-run considerations in outpatient surgery centers that operate at low capacity. An appropriate valuation for long-run considerations and for centers operating near capacity is based on the revenue that centers lose as a result of extended stays. Lost revenue was estimated to be $415 per patient experiencing PONV. CONCLUSIONS: PONV substantially increases the costs incurred by outpatient surgical centers. 相似文献
130.