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1.
Children and youth who are hospitalized for a short or long term become socially isolated from their family, school and classmates. As their isolation increases, so does their vulnerability as a result of disrupted schooling. Research studies suggest different ways of using technologies to overcome this isolation and support children during this critical time of their lives. With technology for children in hospitals becoming increasingly commonplace, evaluating how it is used and its impact on children's learning and well‐being is necessary. In this paper, we systematically evaluated existing research on use of technologies for communication, support and educational purposes and its contribution to the well‐being of hospitalized children. A rigorous selection process yielded 14 research articles meeting the following criteria: empirical studies, using technologies for network of support, targeting hospitalized children and adolescents and targeting learning or social and emotional well‐being in the last decade. This review indicates that the use of technologies with children and youth in hospitals generally increased their potential for learning and improved connectivity with school. Our findings revealed that implementing digital pedagogies and creating online communities were helpful but underutilized features in the research.  相似文献   
2.
Calcium cobaltite Ca3Co4−xO9+δ (CCO) is a promising p-type thermoelectric (TE) material for high-temperature applications in air. The grains of the material exhibit strong anisotropic properties, making texturing and nanostructuring mostly favored to improve thermoelectric performance. On the one hand multitude of interfaces are needed within the bulk material to create reflecting surfaces that can lower the thermal conductivity. On the other hand, low residual porosity is needed to improve the contact between grains and raise the electrical conductivity. In this study, CCO fibers with 100% flat cross sections in a stacked, compact form are electrospun. Then the grains within the nanoribbons in the plane of the fibers are grown. Finally, the nanoribbons are electrospun into a textured ceramic that features simultaneously a high electrical conductivity of 177 S cm−1 and an immensely enhanced Seebeck coefficient of 200 µV K−1 at 1073 K are assembled. The power factor of 4.68 µW cm−1 K−2 at 1073 K in air surpasses all previous CCO TE performances of nanofiber ceramics by a factor of two. Given the relatively high power factor combined with low thermal conductivity, a relatively large figure-of-merit of 0.3 at 873 K in the air for the textured nanoribbon ceramic is obtained.  相似文献   
3.
This paper addresses the discrete network design problem (DNDP) with emphasis on the environmental benefits. These benefits are traditionally quantified by emission models, which in general account for vehicle speeds, traffic flows and emission coefficients. An alternative approach for approximating the environmental impact of traffic is developed. This approach finds the route that keeps the most balanced speed profile throughout the route, which contributes to fuel consumption reduction. The paper formulates an optimization problem that includes the described approach for the DNDP. The solution of the problem consists of projects that contribute the most to the generation of such “balanced speed routes”. The paper illustrates the problem and the solution for a real-size network with a medium-size set of candidate projects.  相似文献   
4.
The removal of various organic micropollutants (OMPs), including six antibiotics (ERY, ROX, CLA, SMX, SMZ, and TMP), three pharmaceuticals (ibuprofen, salicylic acid, and diclofenac), one industrial product (BPA), and one hormone (cholesterol), was investigated in two pilot plants treating the same raw sewage of the Tel-Aviv WWTP. The effluent production by CAS-UF was 45 m3/h while that of MBR was 40 L/h. Each system's effluent constituted the feed for its RO, which comprised three RO steps after the CAS/UF and a semi-batch RO system after the MBR. Despite significant molecular differences between the selected OMPs, high removal rates were achieved after the RO stage (> 99% for macrolides, pharmaceuticals, cholesterol, and BPA, 95% for diclofenac, and > 93% removal of sulfonamides). However, low antibiotics concentrations and 28–223 ng/L residuals of ibuprofen, diclofenac, salicylic acid, cholesterol, and BPA in the MBR/RO and CAS-UF/RO permeates showed that although RO is an efficient removal solution, it cannot serve as an absolute barrier to OMPs. Therefore, additional treatment techniques should be considered to be incorporated aside the RO to ensure complete removal of such substances.  相似文献   
5.
BACKGROUND: The prognosis of patients with brain metastasis as the only manifestation of an undetected primary tumor generally is considered to be poor. Therefore, most treatment is palliative. The authors reviewed the clinical outcomes and treatment results of patients presenting with brain metastasis from an undetected primary tumor at The University of Texas M. D. Anderson Cancer Center. METHODS: Between 1977-1996, 220 patients were referred to the study department for the treatment of brain metastasis from an undetected primary tumor. The patients' records were reviewed to identify those for whom brain metastasis was the only manifestation of the primary tumor. The majority of patients were excluded from the current analysis because extracranial metastasis also were present. Thirty-nine patients qualified for this retrospective review. The level of neurosurgical excision varied, but all patients received radiotherapy. Tumor control in the brain and survival were analyzed by various tumor-related and treatment-related factors. RESULTS: In 31 patients, the brain metastasis were adenocarcinomas, whereas the remaining patients had tumors of various other histologies. In 12 patients, the primary tumor eventually was found, most commonly in the lung. The median survival time for all patients was 13.4 months. Overall survival rates (OS) at 1, 3, and 5 years were 56%, 19%, and 15%, respectively. Intracranial disease control was 72% at 5 years. Patients who received gross total resection (GTR) and radiotherapy had significantly better OS than patients who received radiotherapy alone. The OS of patients whose primary tumor was identified was similar to that of patients in whom the primary tumor remained occult. CONCLUSIONS: Brain metastasis as the only manifestation of an unknown primary tumor is a distinct clinical entity. The prognosis for patients with this presentation is better than that of patients with brain metastasis in general. Although the majority of patients die of extracranial disease, a few will achieve long term survival. Treatment to the brain is effective in controlling local disease; aggressive treatment with GTR and radiotherapy is recommended.  相似文献   
6.
Wheat is the staple food of Punjab province of Pakistan, which contributes more than 75% of the total national production. Accurate and timely forecasting of wheat yield is a cornerstone for monitoring food security and planning for agricultural markets, but the efficiency of the current system for near real-time forecasting should be improved. In this research paper, we developed a model to forecast wheat yield before harvest for each of eight individual districts and for Punjab province as a whole. The model uses weather and Moderate Resolution Imaging Spectroradiometer (MODIS)-derived normalized difference vegetation index (NDVI) data for 2001–2014 (14 years) to calculate Random Forest (RF) statistical models using 15 independent variables. Temperature, rainfall, sunshine hours, growing degree days, and MODIS-derived NDVI for each of the eight districts of Punjab province were used to forecast yield for the year 2014. The same independent variables were used to forecast wheat yield of the whole Punjab from 2001 to 2014 by excluding the respective year from training set. Sunshine hour data were not available for all districts and therefore we tested using temperature data and average latitude-based solar radiation as surrogates. The root mean square errors (RMSEs) of the forecast results of the whole of Punjab province were 147.7 kg ha?1 and 148.7 kg ha?1 with a mean error of less than 5% using average and generic RFs, respectively. Forecasts for individual districts showed R2 of 0.95 with RMSE of 175.6 kg ha?1 and 5.86% mean error.  相似文献   
7.
8.
DAP kinase links the control of apoptosis to metastasis   总被引:1,自引:0,他引:1  
DAP kinase is a new type of calcium/calmodulin-dependent enzyme that phosphorylates serine/threonine residues on proteins. Its structure contains ankyrin repeats and the 'death' domain, and it is associated with the cell cytoskeleton. The gene encoding DAP kinase was initially isolated as a positive mediator of apoptosis induced by interferon-gamma, by using a strategy of functional cloning. We have now tested whether this gene has tumour-suppressive activity. We found that lung carcinoma clones, characterized by their highly aggressive metastatic behaviour and originating from two independent murine lung tumours, did not express DAP kinase, in contrast to their low-metastatic counterparts. Restoration of DAP kinase to physiological levels in high-metastatic Lewis carcinoma cells suppressed their ability to form lung metastases after intravenous injection into syngeneic mice, and delayed local tumour growth in a foreign 'microenvironment' Conversely, in vivo selection of rare lung lesions following injection into syngeneic mice of low-metastatic Lewis carcinoma cells or of DAP kinase transfectants, was associated with loss of DAP kinase expression. In situ TUNEL staining of tumour sections revealed that DAP kinase expression from the transgene raised the incidence of apoptosis in vivo. DAP-kinase transfectants also showed increased sensitivity in vitro to apoptotic stimuli, of the sort encountered by metastasizing cells at different stages of malignancy. We propose that loss of DAP kinase expression provides a unique mechanism that links suppression of apoptosis to metastasis.  相似文献   
9.
Beams of highly ionized, very heavy atoms at moderate velocities have been produced at the UNILAC using the acceleration-stripping-deceleration method. The available ion species range from Kr33+ to U66+ in the energy region between 2 and 5 MeV/u. A survey on first experiments at GSI using these moderate velocity, few electron, heavy ion beams is given. The effectiveness of the method is demonstrated for Xeq+ ?Xe collision experiments with 41 ≤ q ≤ 45. Results on vacancy transfer between inner quasimolecular levels for close collisions, and on distant collision electron capture are reported.  相似文献   
10.
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