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41.
流动人口是一支较为活跃的社会群体,随着社会主义市场经济的迅速发展,流动人口的数量逐年增多,人口的频繁流动,给社会治安、计划生育、城市管理带来许多新情况、新问题、抓好流动人口综合治理与服务工作逐步成为一项重要工作内容. 相似文献
42.
D. Schmoranzer M. La Mantia G. Sheshin I. Gritsenko A. Zadorozhko M. Rotter L. Skrbek 《Journal of Low Temperature Physics》2011,163(5-6):317-344
We report on experimental investigations of acoustic emission by quartz tuning forks resonating at frequencies 32 kHz, 38 kHz, 77 kHz and 100 kHz immersed in cold gaseous 4He and its normal and superfluid liquid phases. Frequency dependence of the observed low-drive-linewidth at 350 mK together with the temperature and pressure dependences (1.3 K < T < 4.2 K, 0 < p < 25 bar) of the observed damping of the high frequency (77 and 100 kHz) resonators measured in normal liquid 4He and its superfluid phase provide strong and direct evidence of the importance of sound emission by these tuning forks. Three analytical models of acoustic emission by vibrating tuning forks are developed and compared with the experimental results. We also discuss the importance of sound emission for experiments with the commonly used 32 kHz tuning forks as well as other oscillating structures??spheres, wires, grids and various micromachined sensors. We compare the relative importance of dissipative losses due to laminar viscous/ballistic drag and acoustic emission in liquid and superfluid 4He. 相似文献
43.
M.C. Maccarone O. CatalanoS. Giarrusso G. La RosaA. Segreto G. AgnettaB. Biondo A. ManganoF. Russo S. Billotta 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,659(1):569-578
UVscope is a portable multi-pixels photon detector developed at IASF-Pa to support experimental activities in the high-energy astrophysics and cosmic rays field. The instrument, working in single photon counting mode, is designed to directly measure light flux in the wavelengths range 300-650 nm. Thanks to its features and operational flexibility, the instrument can be used in a wide field of applications where the knowledge of the environmental luminosity is required, as in the characterization of sites for ground-based Cherenkov and fluorescence telescopes, and for cross-calibration of their cameras.The present version of UVscope is based on a Multi Anode Photo Multiplier Tube and it is completed by a motorized mount and a filter wheel which allow to make low-light measurements, at programmed pointing directions and at different filter wavelengths. In this paper, the instrument is firstly presented in all its components; then the procedures adopted for its absolute and relative calibration are detailed. The performance of UVscope is evaluated and, finally, current and planned scientific applications are described. 相似文献
44.
G. Almonacid G. Nofuentes J. D. Aguilar J. La De Casa A. Garrido 《Progress in Photovoltaics: Research and Applications》1995,3(3):197-209
This paper is directed at evaluating the theoretical potential of an intensive solar intervention in the historical centre of the city of Jaén (Spain). Using the outputs of a solar intervention proposal comprising biomass, photovoltaics and solar thermal domestic hot water (DHW) over a 50-building sample (in which those suitable for solar measures have been selected by evaluating each one over a collection of parameters), energy savings, environmental benefits and economic aspects of the envisaged actions are extrapolated over the entire historical centre. A saving of about 70% of conventional source energy annual consumption and a decrease of some 70% and 73% of CO2 and SOx annual releases, respectively, could be reached with respect to the present situation. Besides, an amount of conventionally generated electricity equivalent to the yearly photovoltaic-generated electricity would require 131500 m3 of water a year, which is a rather significant feature for a dry climate like that of the city. the unitary cost of energy in the new scenario would be 60.7 pta kWh-1 for photovoltaics, 329.9 pta m-3 for DHW using solar thermal installations and 4.6 Pta kWh-1 for biomass heating (1 US$ = 132.7 pta; 1 ECU = 160.9 pta). 相似文献
45.
C. La Tessa L. Di Fino M. Larosa K. Lee D. Mancusi D. Matthiä L. Narici V. Zaconte 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(21-22):3549-3557
The ALTEA-Space detector has been calibrated by testing its response to several monochromatic beams. These measurements provided energy-deposition spectra in silicon of 100, 600 and 1000 MeV/nucleon 12C and 200 and 600 MeV/nucleon 48Ti. The results have been compared to three Monte Carlo transport codes, namely PHITS, GEANT4 and FLUKA. Median, full width at half maximum (FWHM) and interquartile range (IQR) have been calculated for all datasets to characterize location, width and asymmetry of the energy-deposition spectra. Particular attention has been devoted to the influence of δ rays on the shape of the energy-deposition spectrum, both with the help of analytical calculations and Monte Carlo simulations. The two approaches proved that, in this range of projectile charge, projectile energy and detector size, the leakage of secondary electrons might introduce a difference between the energy-loss and energy-deposition spectrum, in particular by changing the location, width and symmetry of the distribution. The overall agreement between the Monte Carlo predictions and the measurements is fair and makes PHITS, FLUKA and GEANT4 all possible candidates for simulating ALTEA-Space experiment. 相似文献
46.
The human serum paraoxonase/arylesterase gene (PON1) is one member of a multigene family 总被引:2,自引:0,他引:2
A physiological role for paraoxonase (PON1) is still uncertain, but it catalyzes the hydrolysis of toxic organophosphates. Evidence that the human genome contains two PON1-like genes, designated PON2 and PON3, is presented here. Human PON1 and PON2 each have nine exons, and the exon/intron junctions occur at equivalent positions. PON1 and PON2 genes are both on chromosome 7 in human and on chromosome 6 in the mouse. Turkey and chicken, like most birds, lack paraoxonase activity and are very susceptible to organophosphates. However, they have a PON-like gene with approximately 70% identity with human PON1, PON2, and PON3. Another unexpected finding is that the deduced amino acid sequences of PON2 in human, mouse, dog, turkey, and chicken and of human PON3 are all missing the amino acid residue 105, which is lysine in human PON1. The expanded number of PON genes will have important implications for future experiments designed to discover the individual functions, catalytic properties, and physiological roles of the paraoxonases. 相似文献
47.
In this thesis, Korean prisoners' health behavior and the characteristics of their medical utilization were surveyed and analysed. Because prisoners are inclined to be mediators of communicable diseases or unhealthy behaviors between prison institution and the outside world, health care for prisoners is directly related to the national population. Data were collected through a self-administered survey of 5 Korean prisons out of a total of 38 correctional facilities and analysed in accordance with a causal model based on a path frame, by serial multiple regressions on health behavior, health status, and medical utilization, etc. According to the survey analysis, while prisoners were generally concerned with their health much more than they were before imprisonment, they perceived that their health status had deteriorated after imprisonment, and that their need for health services was increasing gradually during their time in prison. In the path analysis on the causal relations among variables related to the prisoners' health status and medical utilization, the prisoners' characteristics affected their health concern and health behavior, and subsequently affected their health status and medical utilization, respectively. To sum up these exploratory studies on prisoners' health behavior and health service utilization, some efforts to organize a health care system embracing the correctional institution and health care administration should be made on the level of establishing a health care delivery system for special social groups like prisoners. 相似文献
48.
Mauro Vigan Nicola Pugliese Federica Cerini Federica Turati Vincenzo Cimino Sofia Ridolfo Simone Rocchetto Francesca Foglio Maria Terrin Carlo La Vecchia Maria Grazia Rumi Alessio Aghemo 《International journal of molecular sciences》2022,23(20)
The identification of advanced fibrosis by applying noninvasive tests is still a key component of the diagnostic algorithm of NAFLD. The aim of this study is to assess the concordance between the FIB-4 and liver stiffness measurement (LSM) in patients referred to two liver centers for the ultrasound-based diagnosis of NAFLD. Fibrosis 4 Index for Liver Fibrosis (FIB-4) and LSM were assessed in 1338 patients. A total of 428 (32%) had an LSM ≥ 8 kPa, whereas 699 (52%) and 113 (9%) patients had an FIB-4 < 1.3 and >3.25, respectively. Among 699 patients with an FIB-4 < 1.3, 118 (17%) had an LSM ≥ 8 kPa (false-negative FIB-4). This proportion was higher in patients ≥60 years, with diabetes mellitus (DM), arterial hypertension or a body mass index (BMI) ≥ 27 kg/m2. In multiple adjusted models, age ≥ 60 years (odds ratio (OR) = 1.96, 95% confidence interval (CI) 1.19–3.23)), DM (OR = 2.59, 95% CI 1.63–4.13), body mass index (BMI) ≥ 27 kg/m2 (OR = 2.17, 95% CI 1.33–3.56) and gamma-glutamyltransferase ≥ 25 UI/L (OR = 2.68, 95% CI 1.49–4.84) were associated with false-negative FIB-4. The proportion of false-negative FIB-4 was 6% in patients with none or one of these risk factors and increased to 16, 31 and 46% among those with two, three and four concomitant risk factors, respectively. FIB-4 is suboptimal to identify patients to refer to liver centers, because about one-fifth may be false negative at FIB-4, having instead an LSM ≥ 8 KPa. 相似文献
49.
Latorre L Parisi A Fraccalvieri R Normanno G La Porta MC Goffredo E Palazzo L Ciccarese G Addante N Santagada G 《Journal of food protection》2007,70(6):1507-1512
Listeria monocytogenes is an important foodborne pathogen that causes gastrointestinal disorders, and, especially in immunocompromised people, serious extraintestinal diseases, such as septicemia and meningitis, as well as abortion in pregnant women. Many foods, from both plant and animal origin, have been involved in listeriosis outbreaks. This article reports the results of a 12-year survey (1993 through 2004) on the presence of L. monocytogenes in several kinds of food marketed in Italy. Of 5,788 analyzed samples, 121 (2.1%) were contaminated with L. monocytogenes. The highest prevalence was found in smoked salmon (10.6%) and in poultry meat samples (8.5%) and the lowest in red meat (0.3%). L. monocytogenes was not found in 154 samples of fresh seafood products. Fifty-two isolates were also serotyped by the agglutination method. The most common serotypes detected in the 52 strains tested were 1/2a (36.5%), followed by 1/2c (32.8%), 1/2b (13.5%), 4b (11.5%), 3a (3.8%), and 3b (1.9%). The results of the present study showed low levels of L. monocytogenes in the analyzed samples. A total of 61.5% of the 52 L. monocytogenes strains analyzed belonged to serotypes 1/2a, 1/2b, and 4b, namely the serovars that are most commonly involved in extraintestinal human listeriosis outbreaks. In the ready-to-eat samples, these three serotypes were 40.0% (1/2a), 17.1% (1/2b), and 14.3% (4b). This finding highlights the need to implement strict hygienic measures during the production, distribution, and sale of foods to reduce the risk of foodborne listeriosis in humans to an acceptable level. 相似文献
50.
In this work we report the properties of nanocomposite based on PET with two different samples of organically modified montmorillonites. In particular, we studied the effect of the filler concentration on morphology, rheology, and mechanical performance, focusing our attention on the effect of the degradation phenomena of the clay modifiers. The results indicate that at low clay level the morphology achieved is mainly intercalated. On increasing the filler level, coalescence and/or bad defragmentation phenomena induce a coarser morphology, as confirmed by XRD, SEM, and TEM observations. When a more polar organic modifier is used to modify the clay, the particle adhesion and distribution is slightly better. Conversely, at the processing temperatures adopted, this organic modifier induces a strong degradation of PET, as confirmed by melt rheology and intrinsic viscosity measurements. DSC indicates, in addition, a slight increase of crystallinity likely due to the decreased molecular weight. As regards the mechanical properties, Young's modulus is not significantly changed unless high amounts of clay (10%) are used while the elongation at break drops even at the lowest clay content. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献