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81.
BACKGROUND: Emergency departments (EDs) are recommended as sites for immunizing children. However, there is little information about the effect of ED immunization programs on immunization rates. OBJECTIVES: To assess the ability of 2 ED immunization programs to vaccinate children and to measure the effect of the programs on immunization rates after the ED visit and 6 months later. DESIGN: A prospective cohort study. Emergency department patients were screened for immunization status, and vaccinations were offered to patients who either were documented to be eligible or were eligible by age and had no documented records. A systematic, sequential sample of those accepting vaccinations (study patients) was compared with a systematic, sequential sample of those not vaccinated (control subjects). Telephone interviews and medical record reviews were performed 6 months after the ED visit to verify dates of immunizations. Results were weighted to reflect the sampling frames of patients screened by the 2 programs. SETTING: Two EDs in New York City (in Manhattan and the Bronx) and the surrounding primary care offices. PATIENTS: Children (aged 0-6 years) screened for immunization status by the ED immunization program during a 10-week period; these included 210 children from the Manhattan ED (106 vaccinated in the ED) and 274 children from the Bronx ED (129 vaccinated in the ED). INTERVENTION: Emergency department immunizations. MAIN OUTCOME MEASURES: Proportion of patients (vaccinated, not vaccinated, and ED population) up-to-date for immunizations (1) at the time of the ED visit, (2) 1 day later, and (3) 6 months later. RESULTS: Two thirds of the patients in each ED had Medicaid, and one tenth were uninsured. At the time of the ED visit, 20% of the vaccinated children in each ED were actually up-to-date and were unnecessarily vaccinated; 74% (Manhattan ED) and 72% (Bronx ED) of the not vaccinated children were up-to-date (the remainder were later determined to have been eligible for vaccinations). One day after the ED visit, and 6 months later, the immunization rates of the vaccinated and not vaccinated children were similar. The results of the weighted analysis were as follows: for the entire ED population screened for immunization status, compared with up-to-date rates at the time of the ED visit, rates 1 day later were 11% (Manhattan ED) and 8% (Bronx ED) higher in each ED (P < .05); and rates 6 months later were the same in the Manhattan ED and 10% lower in the Bronx ED (P < .01). Eighteen percent of all children screened for immunization status were vaccinated; 10 to 15 children were screened and 2 to 4 children were vaccinated per 8-hour ED shift. CONCLUSIONS: This ED immunization program temporarily improved the immunization rates of the ED population, but substantial personnel time was required to achieve these small gains. Urban ED immunization programs are unlikely to be cost-effective.  相似文献   
82.
This work presents an automated solution for tool changing in industrial robots using visual servoing and sliding mode control. The robustness of the proposed method is due to the control law of the visual servoing, which uses the information acquired by a vision system to close a feedback control loop. Furthermore, sliding mode control is simultaneously used in a prioritised level to satisfy the constraints typically present in a robot system: joint range limits, maximum joint speeds and allowed workspace. Thus, the global control accurately places the tool in the warehouse, but satisfying the robot constraints. The feasibility and effectiveness of the proposed approach is substantiated by simulation results for a complex 3D case study. Moreover, real experimentation with a 6R industrial manipulator is also presented to demonstrate the applicability of the method for tool changing.  相似文献   
83.
A new metallic thin-film thermocouple orientated towards thermoelectric microgenerators has been developed. It consists of a 3 μm thick NiCr/SiO2/Sb multilayer structure sputter deposited onto a thermally oxidized silicon substrate. A relative Seebeck coefficient of ab = 76 μV K−1 and an optimal figure of merit of zab = 0.08 × 10−3 K−1 have been measured for this material combination. Both parameters are very close to the theoretical values.  相似文献   
84.
A comparative study on recent works on low noise amplifiers (LNAs) designed to be operated at mobile communication band is performed in this article. Here, specifications of different generations of mobile communication are listed, which are considered to classify recent works on LNAs. Even though gain and noise figure (NF) are the primary parameters of LNA; other parameters like power, linearity, bandwidth, and area also get importance. Due to this, optimization techniques handpicked for all those parameters are discussed. The inverse relation between gain and NF is exploited to achieve low noise and high gain together. While increasing the gain, power consumption is increased by drain current. Each LNA is found as good in terms of gain and other parameters to satisfy the requirements. The figure of merit is opted to find the performance of each LNA, and the comparison is performed. The best parameters reported in the comparison are 31.53 dB of gain, 0.7 dB of NF, 0.03 mw of power consumption, 18.14 dBm of third‐order input intercept point (IIP3), 24 GHz bandwidth and 0.0052 mm2 of area at different frequencies and technology nodes. In this survey, as per the optimized FoM for mobile communication, cross‐coupled common gate differential LNA, which was designed to be operated at 0.3 to 2.96 GHz gives better results among CMOS LNAs.  相似文献   
85.
Dielectric analysis and differential scanning calorimetry were used to study the cure reaction of an epoxy resin (the diglycidyl ether of bisphenol A (DGEBA) (n = 0)) and two curing agents, ie 1,2‐diamine cyclohexane (1,2‐DCH) and m‐xylylenediamine (m‐XDA). Various dielectric properties, such as the relaxed permittivity, unrelaxed permittivity and dipole strength, were determined as a function of the curing time, temperature and conversion. The dielectric curing properties observed were related to geometric and energetic aspects of the samples. Analysis of the results shows that the relaxed permittivity and dipole strength are higher for the system DGEBA (n = 0)/1,2‐DCH than for the system DGEBA (n = 0)/m‐XDA. Copyright © 2005 Society of Chemical Industry  相似文献   
86.
In this paper, a new model for the prediction of the cumulative distribution function of fatigue life of structural elements during the crack propagation stage is established. This problem is considered as a cumulative damage process following the probabilistic approach of Bogdanoff and Kozin (B-models). The initial and final crack lengths, the crack propagation angle, the material fracture and elastic parameters and the external loads have been the random variables considered here. The theoretical bases of the model and the procedure to construct it are described in the forthcoming paragraphs such as several examples for mode I problems including the comparison with experimental results.  相似文献   
87.
A new circular position sensor based on giant magnetoresistances has been developed. The sensing film is an AgCo nanogranular thin film patterned in a circular Wheatstone bridge configuration. This alloy shows a high magnetoresistance (8%) at room temperature within the field generated by an NdFeB permanent magnet that provides a sensitivity of 440 /spl mu/V/V/(/spl deg/). The operational temperature range of this sensor is -40/spl deg/C/+120/spl deg/C, although the magnetic film tolerates higher temperatures up to 200/spl deg/C. These parameters and the contactless way of sensing make this device appropriate for automotive applications. The developed sensor presents excellent characteristics for life, since it is not sensitive to pollution; it is frictionless and does not present any type of electrical noise generated by contacts.  相似文献   
88.

Chitosan microbeads with C-doped TiO2, N-doped TiO2 and C,N-codoped TiO2 were prepared to obtain photocatalysts with higher photocatalytic efficiency, active under visible light and easy to removed from aqueous medium. TiO2 powders were synthesized by the sol–gel method and modified using glucose and ammonium nitrate as source of C and N, respectively. Scanning electron microscope (SEM), X-ray diffraction (XRD), DRUV–Vis spectra and Raman techniques, were used to characterize the modified TiO2 powders. The structural and physicochemical properties of the microbeads were analyzed by nitrogen physisorption, functional groups were identified by Fourier transform Infrared (FT-IR) spectroscopy and microbeads were observed by optical microscopy. The microbeads photocatalytic efficiency under visible light was evaluated monitoring the E. coli growth-inhibition, determined by colony count analysis (CFU—colony forming units). Results showed effectiveness in all tested composites to inhibit E. coli growth in 24 h under visible light. Furthermore chitosan microbeads with C,N-codoped TiO2 showed the best performance in the degradation test being the most effective composite to achieving 99.99% of E. coli growth inhibition in less than 4 h.

  相似文献   
89.
In the present study, a cassava starch-glycerol film with reinforcement of Pinus sp. nanofibers (NFC) incorporated with tea tree (Melaleuca alternifolia) essential oil (TTO) were prepared by casting technique. The physical (barrier, mechanical, and optical), structural, and antimicrobial properties of the films were evaluated and compared with the control films. Films with 0.08% TTO exhibited a significant increase in the tensile strength (TS) while films with 1.5% TTO showed a decrease in TS, suggesting a crosslinking effect. The addition of 1.5% TTO reduced the water vapor permeability values in 43% comparing to the control films. Analysis obtained by Fourier transform infrared spectroscopy showed bands related to the interaction between TTO and matrix for films with 1.5% TTO and 0.3% NFC. This film was effective against Staphylococcus aureus and Candida albicans which could be applied for several packaging purposes. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48726.  相似文献   
90.
Line coding is used to tune the wave form based on the properties of the physical channel. Bi-Phase Mark Coding (BMC), Bi-Phase Space Coding (BPSC) and Phase Coding (PC) are used as Line coding techniques. The first objective of the proposed work is to design Generation and Degeneration operations of BMC, BPSC and PC techniques in a single chip. The second objective is to reduce the area and power consumption, by modifying the number of MOS devices used to design the system and by adjusting the width of the MOS devices. The proposed system is designed with 59 transistors and simulated using Cadence® 90 nm technology. This occupies 1290 µm2. Required power can be reduced up to 33% by using any one of the suitable coding among BMC, BPSC and PC based on the properties of the input data signal. If the input data has equal possibility of high and low level signals, PC technique will be suitable for power reduction. If the high level beats the low level, BPSC technique will be suitable. If the low level beats the high level, BMC technique will be suitable.  相似文献   
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