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1.
The potential use of stem cell-based therapies for the repair and regeneration of various tissues and organs is a major goal in repair medicine. Stem cells are classified by their potential to differentiate into functional cells. Compared with other sources, adipose-derived stem cells (ADSCs) have the advantage of being abundant and easy to obtain. ADSCs are considered to be tools for replacing, repairing, and regenerating dead or damaged cells. The capacity of ADSCs to maintain their properties depends on the balance of complex signals in their microenvironment. Their properties and the associated outcomes are in part regulated by reactive oxygen species, which mediate the oxidation-reduction state of cells as a secondary messenger. ADSC therapy has demonstrated beneficial effects, suggesting that secreted factors may provide protection. There is evidence that ADSCs secrete a number of cytokines, growth factors, and antioxidant factors into their microenvironment, thus regulating intracellular signaling pathways in neighboring cells. In this review, we introduce the roles of ADSCs in the protection of cells by modulating inflammation and immunity, and we develop their potential therapeutic properties.  相似文献   
2.
Understanding the sources and composition of organic aerosol (OA) in indoor environments requires rapid measurements, since many emissions and processes have short timescales. However, real-time molecular-level OA measurements have not been reported indoors. Here, we present quantitative measurements, at a time resolution of five seconds, of molecular ions corresponding to diverse aerosol-phase species, by applying extractive electrospray ionization mass spectrometry (EESI-MS) to indoor air analysis for the first time, as part of the highly instrumented HOMEChem field study. We demonstrate how the complex spectra of EESI-MS are screened in order to extract chemical information and investigate the possibility of interference from gas-phase semivolatile species. During experiments that simulated the Thanksgiving US holiday meal preparation, EESI-MS quantified multiple species, including fatty acids, carbohydrates, siloxanes, and phthalates. Intercomparisons with Aerosol Mass Spectrometer (AMS) and Scanning Mobility Particle Sizer suggest that EESI-MS quantified a large fraction of OA. Comparisons with FIGAERO-CIMS shows similar signal levels and good correlation, with a range of 100 for the relative sensitivities. Comparisons with SV-TAG for phthalates and with SV-TAG and AMS for total siloxanes also show strong correlation. EESI-MS observations can be used with gas-phase measurements to identify co-emitted gas- and aerosol-phase species, and this is demonstrated using complementary gas-phase PTR-MS observations.  相似文献   
3.
A therapist's theoretical orientation is likely to influence every facet of the therapeutic process. We explore the relationship of therapeutic orientation and self-monitoring style. To test the hypothesis that high self-monitors would be more eclectic than low self-monitors, we surveyed 30 intake therapists at a child guidance center. Results supported the hypothesis; those frequently using more than one orientation had higher self-monitoring scores. Furthermore, self-monitoring correlated negatively with psychoanalytic endorsement, but in a positive direction with behavioral, systems and eclectic endorsements. Results are discussed in terms of training needs of those differing in self-monitoring style. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
4.
Chemometric tools were used to generate the modelling of solvent e inverted exclamation markects on the N-alkylation of an isocyanuric acid salt. The method proceeded from a central composite design applied on the Carlson solvent classification using principal components analysis. The selectivity of the reaction was studied from the production of different substituted isocyanuric derivatives. Response graphs were obtained for each compound and used to devise a strategy for solvent selection. The prediction models were validated and used to search for the best selectivity for the reaction system. The solvent most often selected as the best for the reaction is the N,N-dimethylformamide.  相似文献   
5.
The current study prospectively followed girls with attention-deficit/hyperactivity disorder (ADHD), along with a matched comparison sample, 5 years after childhood neuropsychological assessments. Follow-up neuropsychological measures emphasized attentional skills, executive functions, and language abilities. Paralleling childhood findings, the childhood-diagnosed ADHD group displayed moderate to large deficits in executive/attentional performance as well as in rapid naming relative to the comparison group at follow up (Mage 14.2 years). ADHD-inattentive versus ADHD-combined contrasts were nonsignificant and of negligible effect size, even when a refined, sluggish cognitive tempo subgroup of the inattentive type was examined. Although ADHD versus comparison group differences largely withstood statistical control of baseline demographics and comorbidities, control of childhood IQ reduced executive function differences to nonsignificance. Yet when the subset of girls meeting diagnostic criteria for ADHD in adolescence was compared with the remainder of the participants, neuropsychological deficits emerged even with full statistical control. Overall, childhood ADHD in girls portends neuropsychological and executive deficits that persist for at least 5 years. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
Connecting people across the “digital divide” is as much a social effort as a technological one. We are developing a community-centred approach to learn how interaction techniques can compensate for poor communication across the digital divide. We have incorporated the lessons learned regarding social intelligence design in an abstraction and in a device called the SoftBridge. The SoftBridge allows communication to flow from endpoints through adapters, getting converted if necessary, and out to destination endpoints. Field trials are underway with two communities in South Africa: disadvantaged Deaf users and an isolated rural community. Initial lessons learned show that we have to design user interfaces that allow users to understand and cope with delay. We also learned that social concerns are often more important than the technical issues in designing such systems.  相似文献   
7.
A dual-staged nanofiltration process is being evaluated as an alternative to reverse osmosis for seawater desalination. The primary goal of this system is to reduce energy consumption while producing potable water at an acceptable recovery rate. Investigation of this system at the bench-scale level focused on membrane surface characterization, ion rejection (including boron, bromide, and iodide rejection), and flux decline. Results from this study showed that two commercially available nanofiltration membranes can effectively desalinate seawater. Although fouling was apparent—and resulted in approximately 20% flux decline over 3 days—a critical flux was not identifiable. Operation of the system at different cross-flow velocities revealed the significance of hydrodynamic conditions on the polarization modulus, and hence on membrane performance.  相似文献   
8.
Assessed whether women self-handicap with alcohol consumption prior to engaging in a social evaluation task, which may be more relevant to their self-esteem than the intellectual tasks used in past self-handicapping studies on substance use. 113 women (aged 19–32 yrs), who were evaluated as normal drinkers, performed either a solvable or an insolvable social judgment task and then received either success feedback or no feedback. Ss received access to alcoholic and nonalcoholic beverages while awaiting a retest. The study terminated before the retest. The self-handicapping hypothesis that noncontingent success would produce relatively greater alcohol consumption was not supported. Regardless of feedback, insolvable test Ss consumed more alcohol than did solvable test Ss. Findings suggest that the hypothesis may be limited as a general model of alcohol consumption in both sexes. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
Reaction of metallic fluorides: WF6 TaF5, NbF5 and TiF4 with C60/C70 extract was performed at appropriate temperatures. M0F5 and BF3 fluorides do not react. Chemical formulas based on mass uptake show MFn/C60 ratios up to 2.00. Compounds were analysed by means of X-ray diffraction, FT-IR and NMR spectroscopies. The presence of neutral fluorides and associated anionic species is put forward and it is shown that MFn compounds do not act as fluorination agents. Electrical conductivity measurements are also presented.  相似文献   
10.
This paper introduces results on placement and communications minimization for systems of affine recurrence equations. We show how to classify the dependences according to the number and nature of communications they may result in. We give both communication-free conditions and conditions for an efficient use of broadcast or neighbor-to-neighbor communication primitives. Since the dependences of a problem can generally not be all communication-free, we finally introduce a heuristic to globally minimize the communications based on the classification of dependences.  相似文献   
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