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1.
The inorganic stannous-based perovskite oxide SrSnO3 has been utilized in various optoelectronic applications. Facilitating the synthesis process and engineering its properties, however, are still considered challenging due to several aspects. This paper reports on a thorough investigation of the influence of rare-earth (praseodymium) doping on the microstructural and optoelectronic properties of pure and Pr-doped SrSnO3 perovskite oxide thin films synthesized by a two-step simple chemical solution deposition route. Structural analysis indicated the high quality of the obtained phase and the alteration generated from the insertion of impurities. Surface scanning illustrated the formation of homogenous and crack-free SrSnO3 thin films with a nanorod morphology, with an augmentation in size as the dopant ratios increased. Optical properties analysis showed an enhancement in the samples optical absorption with wide-range bandgap tuning. First-principles calculations revealed the exchange interactions between the 3d–4f states and their impact on the electronic properties of the pristine material. Hall-effect measurements revealed an immense decrement in the resistivity of the films upon increment of doping ratios, passing from 7.3 × 10−2 Ω cm for the undoped sample to 4.8 × 10−2 Ω cm for 7% Pr content, while a reverse trend was observed on the carrier mobility, rising from 2.5 to 7.6 cm2 V−1 s−1 for 7% Pr content. The results emphasized the efficiency of the simple synthesis route to produce high-quality samples. The current findings will contribute to paving the way towards expanding the utilization of simple and cost-effective chemical solution deposition methods for the fast and large area growth of stannous-based perovskite oxides for optoelectronic applications.

Unraveling the optical, electronic and electrical properties of high-quality nanorod morphology spray-coated Pr-doped SrSnO3 perovskite oxide thin films.  相似文献   
2.
130 critically ill patients undergoing long term mechanical ventilation were divided into two groups, tracheotomy versus translaryngeal intubation. There were no difference in demographic characteristics between the two groups. The incidence of chronic obstructive pulmonary disease (COPD) was also higher in T. The tracheotomy was achieved at mean within 14 days after the beginning of mechanical ventilation. The incidence of pneumonia is the same in the two groups (41% for T versus 39% for I). The length of mechanical ventilation is longer in T (25 +/- 12 d versus 12 +/- 4 d). The COPD represent a risk factor for prolonged mechanical ventilation in T (18 days in COPD patients with tracheotomy versus 9 days in non COPD patients). The length of stay in intensive care unit is higher in T (29 +/- 13 d versus 15 +/- 4 d). The 28th day mortality is similar between the two groups. The tracheotomy didn't allow a shorter duration of mechanical ventilation. That's can be explain by the fact that we performed the tracheotomy in a high risk population for pulmonary complications (COPD) and often after a first failure of weaning form mechanical ventilation.  相似文献   
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OBJECTIVE: To understand gender differences in sexual behaviours in response to genitourinary symptoms. METHODS: 473 (239 female and 234 male) subjects were enrolled at an STD clinic regardless of symptoms or infection status. Subjects completed a 30 day calendar recall interview of genitourinary symptoms, coital activity, sexual partners, and condom use. RESULTS: Of the total of 473 participants, 261 (55%) reported symptoms (61% women and 39% men). STI prevalence was 73% and 75% for symptomatic women and men, respectively. For black women the probability of coitus was decreased in the presence of vaginal discharge (OR 0.64, 95% CI 0.47 to 0.89). No change in coital activity was seen in non-black women in the presence of vaginal discharge. Having vaginal discharge did increase the likelihood of condom use by their partners (OR 2.48, 95% CI 1.05 to 5.88), if coitus occurred. Urethral discharge was not associated with coitus or condom use in men. However, in men, dysuria was associated with increased likelihood of condom use (OR 4.25, 95% CI 1.57 to 11.56) if coitus occurred. CONCLUSION: Black women altered both coital activity and condom use behaviours in response to vaginal discharge. In contrast, non-black women did not modify coital activity. Men increased condom use when having dysuria but did not alter coital activity. Changes in sexual behaviours may alter the risk of STI transmission independent of interactions with the healthcare system. STI education and prevention programmes need to better understand these gender and racial differences in developing effective strategies to reduce STI transmission.  相似文献   
4.
Quantitative analysis in positron emission tomography imaging usually necessitates several studies carried out under the same protocol in order to get functional or metabolic parameter values with low variations. Apart from subject preparation and measurements in similar conditions, the data analysis should be done as uniformly as possible. In this work we report PET data obtained in normal and ischemic rats, measured with (13)N-ammonia and (11)C-acetate to extract myocardial blood flow and oxygen consumption, and analysed with the usual region of interest (ROI) drawing method in each rat individually, in comparison to a new method based on resampling all the rat heart images to a common model, then the ROIs are drawn once and copied onto each rat image sequence.  相似文献   
5.
The number of axons in the optic nerve of the ovoviviparous reptile Vipera aspis was estimated from electron micrographs taken during the first 5 weeks of postnatal life. One to two days after birth, the optic nerve contains about 170,000 fibres, of which about 9% are myelinated. At the end of the fifth postnatal week, the number of optic fibres has fallen to about 100,000, of which about 42% are myelinated. This fibre loss continues after the fifth postnatal week, since in the adult viper the nerve contains about 60,000 fibres, of which 85% are myelinated; overall, about 65% of the optic nerve fibres present at birth disappear before the number of axons stabilises at the adult level. This study shows, for the first time, that the mode of development of the visual axons of reptiles is not that of anamniote vertebrates but similar to that of birds and mammals.  相似文献   
6.

Objectives

Studies have shown that having a baseline mammogram, the first screening mammogram, available for comparison at the time of interpreting a subsequent mammogram significantly decreases the potential of a false-positive examination. Our aim was to evaluate knowledge of and perception about the significance of baseline mammograms in those women undergoing screening mammography.

Materials and Methods

A cross-sectional prospective survey study was conducted in women without a history of breast cancer presenting for their screening mammogram. Respondents were surveyed anonymously between March and April 2017. The questionnaire was developed by primary care providers and radiologists and pretested for readability and clarity.

Results

In all, 401 women (87% white, 93% educated beyond high school) completed surveys in which 77% of women reported having yearly mammograms, 31% reported having a history of an abnormal mammogram, and 45% had not heard the term baseline mammogram. Of those who had heard the term, the most commonly reported source was their primary care provider (31%). Although 74% chose the correct definition of a baseline mammogram, 67% did not think that a baseline mammogram was important for decreasing associated cost, time, and discomfort due to the number of mammograms incorrectly read as abnormal.

Conclusion

In a group of educated women who routinely get mammograms, almost one-half had not heard the term baseline mammogram. Furthermore, most women did not think baseline mammography was important for decreasing associated cost, time, and discomfort due to mammograms incorrectly read as abnormal. This study suggests that efforts to improve women’s understanding of baseline mammograms and their importance are warranted, with greatest opportunity for health care providers and radiologists.  相似文献   
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Thinners are organic solvents widely used in industrial applications, but they have also been subject to abuse by inhalation for their psychoactive and rewarding properties. In spite of the prevalence of inhalant abuse, the addictive potential and pathways mediating their reinforcing effects are not yet fully understood and thus still subject of further investigations. Here, we assessed in mice the locomotor activity and the ability of paint thinner to reinforce the conditioning in the place preference paradigm following acute (1 day), subchronic (6 weeks) and chronic (12 weeks) exposures to 300 and 600 ppm of thinner vapor. While locomotor activity was unaffected by the different thinner treatments, a positive conditioned place preference to inhaled thinner was found upon subchronic and chronic exposures. To investigate the activated brain structures underlying such behavioural changes, we analyzed the distribution of c‐Fos immunoreactivity, a marker for neuronal activation, following acute and repeated exposures to 600 ppm of thinner. Notably, thinner exposure increased the number of c‐Fos immunoreactive neurons with increasing duration of exposure in the majority of structures examined; including those typically involved in the processing of rewarding or emotionally stimuli (e.g., ventral tegmental area, core and shell of nucleus accumbens, amygdala, bed nucleus of the stria terminalis, and cingulate cortex), and olfactory stimuli (e.g., piriform cortex and olfactory tubercle). Moreover, prolonged, but not acute thinner inhalation significantly increased c‐Fos immunoreactivity in all hippocampal subregions. Taken together, the expanded distribution of thinner‐induced c‐Fos expression may underlie the observed positive reinforcement upon long‐term thinner inhalation.  相似文献   
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