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1.
There is no better place to test life-saving resuscitation interventions than in the prehospital setting. Patients rarely survive cardiac arrest if resuscitation techniques have failed before leaving the scene. Also, paramedics are usually very experienced in key initial resuscitative techniques, and they routinely operate under strict paramilitary protocol, resulting in better study compliance. In addition, the large study populations that are derived from emergency medical services (EMS) systems lead to faster study completion and statistically stronger data. Most important, by reinforcing standardized care, rigidly scrutinized trials improve patient care, regardless of the effect of the study intervention. The success of productive EMS research centers requires routine communication between hospital and EMS administrators and their medical directors, designation of mutually acceptable data collectors who guarantee confidentiality, reciprocal exchange of study data provided as educational seminars to the hospitals, commitments to support the budget requests of an EMS program and appropriate system modifications, inclusion of EMS personnel in study design from the very beginning, prospective education of the medical community and media before protocol implementation, an authoritative grassroots medical director, and a paramedic supervisor system.  相似文献   
2.
Microsystem Technologies - Micro-mechanical systems (MEMS) based piezoresistive pressure sensors have significant importance in several pressure sensor devices in real world, i.e., aviation, IoT...  相似文献   
3.
This study used Complier Average Causal Effect analysis (CACE; see G. Imbens & D. Rubin, 1997) to examine the impact of an adaptive approach to family intervention in the public schools on rates of substance use and antisocial behavior among students ages 11-17. Students were randomly assigned to a family-centered intervention (N = 998) in 6th grade and offered a multilevel intervention that included (a) a universal classroom-based intervention, (b) the Family Check-Up (selected; T. J. Dishion & K. Kavanagh, 2003), and (c) family management treatment (indicated). All services were voluntary, and approximately 25% of the families engaged in the selected and indicated levels. Participation in the Family Check-Up was predicted by 6th-grade teacher ratings of risk, youth reports of family conflict, and the absence of biological fathers from the youths' primary home. Relative to randomized matched controls, adolescents whose parents engaged in the Family Check-Up exhibited less growth in alcohol, tobacco, and marijuana use and problem behavior during ages 11 through 17, along with decreased risk for substance use diagnoses and police records of arrests by age 18. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
4.
In this paper, islanding detection in the presence of different technologies of distributed generations (DGs) is discussed. Three types of DGs, namely a synchronous generator (SG), a wind energy conversion system (WECS), and a photovoltaic (PV) system, with distribution network parameters as well as linear and nonlinear loads are simulated using the Power System Computer Aided Design/Electromagnetic Transients Including DC (PSCAD/EMTDC) software. To detect the island state, a comprehensive islanding detection algorithm based on wavelet transform (WT) and rate of change of frequency (ROCOF) relay method is considered. To determine the islanding threshold value, the voltage and frequency values of sensitive buses are sampled at regular intervals, and the signals are analyzed with WT using MATLAB. The proposed algorithm could detect the exact island state definitively with the consideration of various disturbance signals such as capacitor bank switching, induction motor switching, and the sudden disconnection of power sources and loads from different buses of the distribution network. The results of the simulation are validated with the logic of ROCOF relay islanding detection method, which determines the accuracy threshold value when the power generation and load consumption difference is negligible. In addition, the proposed algorithm based on the rested DG's output power in the islanding state can supply prioritized loads based on thier importance. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
5.
Maternal depression is associated with problematic parenting and the development of emotional and behavior problems in children and adolescents. While emotional regulatory abilities are likely to influence emotional exchanges between parents and teens, surprisingly little is known about the role of emotion regulation during parent–child interactions, particularly in high-risk families. Respiratory sinus arrhythmia (RSA) has been widely linked to emotion regulatory abilities in recent research, and the current study investigated RSA and maternal depression in relation to dyadic flexibility, as well as mutuality of negative and positive affect displayed during three discussion tasks between 59 mother–adolescent pairs (age 11–17 years). Dyadic flexibility was predicted by the interaction of maternal depression, maternal RSA, and teen RSA, with higher maternal RSA predicting greater dyadic flexibility, particularly in highest risk dyads (i.e., elevated maternal depression and lower teen RSA). Teen RSA interacted with maternal depression to predict mutual negative affect, serving as a protective factor. Finally, maternal and teen RSA interacted to predict mutual positive affect, with maternal RSA buffering against low teen RSA to predict higher mutual positive affect. Results support the role of RSA in affectively laden interactions between parents and adolescents, particularly in the face of maternal depression. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
6.
The template assembled synthetic peptide constructs (TASP), pentavalently presenting the tripeptide KPR or RPK, are potent and specific inhibitors of human immunodeficiency virus (HIV) infection by preventing viral entry into permissive cells. Here the 5[KPsi(CH2N)PR]-TASP construct, Psi(CH2N) for reduced peptide bond, was used in studies to demonstrate its specific binding to a 95-kDa cell surface protein ligand. Compared to its nonreduced 5[KPR]-TASP counterpart, the pseudopeptide 5[KPsi(CH2N)PR]-TASP manifested higher affinity to bind to its cell surface ligand, increased activity to inhibit HIV infection, and resistance to degradation when incubated in serum from an HIV-1 seropositive individual. In ligand blotting experiments, the biotin-labeled 5[KPsi(CH2N)PR]-TASP identified a single 95-kDa protein in crude cell extracts. This 95-kDa protein (p95) is expressed on the cell surface since surface iodination of cells resulted in its labeling, and moreover, following incubation of cells with the biotin-labeled 5[KPsi(CH2N)PR]-TASP, the p95.TASP complex was recovered by affinity chromatography using avidin-agarose. All anti-HIV TASP constructs but not their control derivatives affected the binding of biotin-labeled 5[KPsi(CH2N)PR]-TASP to p95, thus emphasizing the specific nature of this binding. Since 5[KPsi(CH2N)PR]-TASP does not interact with HIV-envelope glycoproteins, our results suggest that TASP inhibitors mediate directly or indirectly a block in HIV-mediated membrane fusion process by binding to the cell surface expressed p95.  相似文献   
7.
Digital signal processing methods, in the broad sense, involve the extraction of useful information from received signals using digital computers and/or digital filters. Digital filters refer to equipment which use digital components such as gates, multipliers, and delay circuits. The analysis of digital signal processing methods, given in most of engineering literature, is done in frequency rather than time domain. This paper presents methods for the analysis of digital systems entirely in the time domain. It discusses such topics as discrete Fourier transform, quadrature components, mechanization of digital filters, and quantization errors.  相似文献   
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9.
Several methods of testing for reliability of engineering systems and equipment are currently available, together with applicable theoretical background. One of the more common methods is sequential testing, where tests are continued until a decision is reached as to product acceptability. Assuming an exponential survival curve outline the theory and procedures involved in carrying out these tests.The present paper gives a method for simulating reliability tests on digital computers whereby additional information such as the probability of completing the tests as a function of time can be obtained. The described Monte Carlo simulation uses exponential product survival characteristics and utilizes mathematical methods for saving computation time. The outlined computer method gives the user the flexibility of devising his own reliability testing procedures. The paper includes a numerical example and compares the results obtained from the computer program with those computed from theoretical formulas.  相似文献   
10.
The authors examined the longitudinal effects of the Family Check-Up (FCU) on parents' positive behavior support and children's school readiness competencies in early childhood. It was hypothesized that the FCU would promote language skills and inhibitory control in children at risk for behavior problems as an indirect outcome associated with targeted improvements in parents' positive behavior support. High-risk families in the Women, Infants, and Children Nutrition Program participated in a multisite preventive intervention study (N = 731) with 3 yearly assessments beginning at child age 2 years. Positive behavior support was measured using 4 indicators derived from at-home observations of parent-child interaction during semistructured tasks. Longitudinal structural equation models revealed that parents in families randomly assigned to the FCU showed improvements in positive behavior support from child age 2 to 3, which in turn promoted children's inhibitory control and language development from age 3 to 4, accounting for child gender, ethnicity, and parental education. Findings suggest that a brief, ecological preventive intervention supporting positive parenting practices can indirectly foster key facets of school readiness in children at risk. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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