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153.
We propose biofunctionalized nanofluidic slits (nanoslits) as an effective platform for real-time fluorescence-based biosensing in a reaction-limited regime with optimized target capture efficiency. This is achieved by the drastic reduction of the diffusion length, thereby a boosted collision frequency between the target analytes and the sensor, and the size reduction of the sensing element down to the channel height comparable to the depletion layer caused by the reaction. Hybridization experiments conducted in DNA-functionalized nanoslits demonstrate the analyte depletion and the wash-free detection ∼10 times faster compared to the best microfluidic sensing platforms. The signal to background fluorescence ratio is drastically increased at lower target concentrations, in favor of low-copy number analyte analysis. Experimental and simulation results further show that biofunctionalized nanoslits provide a simple means to study reaction kinetics at the single-pixel level using conventional fluorescence microscopy with reduced optical depth. 相似文献
154.
Danuta Ro?? Przemys?aw Adamczyk Joanna Boinska Robert Szafkowski Irena Ponikowska Katarzyna Stankowska Barbara Góralczyk Barbara Ruszkowska-Ciastek 《Journal of Zhejiang University. Science. B》2015,16(5):404-411
Objective
The aim of this study was to evaluate the concentrations of C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and the degree of homeostasis model assessment-insulin resistance (HOMA-IR) in patients with morbid obesity exposed to a three-week low-calorie diet and balneotherapy.Methods
The study included 33 patients (25 females and 8 males; mean age 46 years) with body mass index (BMI) values of >40 kg/m2. Evaluations of CRP, IL-6, TNF-α, lipid profile, HOMA-IR, and fasting glucose were carried out before (baseline data) and three weeks after the treatment. The control group consisted of 20 healthy volunteers (15 females and 5 males) with a mean age of 39 years and BMI values of ≤24.9 kg/m2.Results
In the blood of patients with morbid obesity we found significantly elevated levels of CRP, TNF-α, triglycerides, HOMA-IR and fasting glucose, but a decreased level of high density lipoprotein (HDL)-cholesterol, compared with the healthy individuals. The treatment resulted in about a 9.4% reduction in body weight from 122.5 to 111.0 kg and a significant decrease in the concentration of CRP, but no change in TNF-α or IL-6. HOMA-IR was significantly reduced.Conclusion
The decrease in CRP level without changes in TNF-α or IL-6 concentrations after the low-calorie diet and balneological treatment, suggests that an essential amount of adipose tissue must be removed before proper adipocyte function is restored. The decrease in HOMA-IR indicates an improvement in insulin sensitivity, which is beneficial in obese patients.155.
This paper focuses on sustainability strategies for the Forestry–Wood chain (FWC) driven by market demands on books and other products. The main objective is to draft and suggest a process for market driven pro-active sustainability strategies for the FWC, based on a SWOT-analysis (strengths, weaknesses, opportunities and threats). Further to highlight the possible strategic implications and critical areas for actors upstream in the FWC, in the context of uncertain external future scenarios. Higher demands on product differentiation were found throughout the FWC, where also collaboration and stakeholder interaction was found important to improve sustainability. The work broadens the “traditional” perspectives on FWC sustainability to encompass also interacting value chains such as book production and publishing, to get a more holistic view. 相似文献
156.
The purpose of the present investigation was to examine young diplomats’ socialization to the professional expert culture
of the Ministry for Foreign Affairs of Finland over a six-month on-job training period, as part of their preparation for service
in the diplomatic corps. Using social network analysis, we analyzed departments’ internal social structures, prevailing social
relations, and the young diplomats’ role and position in the networks of knowledge acquisition, practical know-how, and professional
collaboration. Data collected by contextual event sampling and theme interviews and analyzed by qualitative content analysis
were used to characterize the young diplomats’ personal social support networks, resources obtained, as well as associated
reflections regarding their functioning in and socialization to the departmental workplace community. The results indicated
that across the six-month training period, the young diplomats became involved to the workplace communities’ networked expertise
and were socialized to its expert culture, even if their achieved networking positions differed. The results revealed differences
between levels of collective operational practices in the workplace communities as well as the nature of assignments in which
the young diplomats participated and for which they were responsible. It was proposed that these differences mirrored distinction
between expansive natures of young diplomats’ workplace communities as learning environments. 相似文献
157.
In this article we intend to contribute to the understanding of interest-driven learning which occurs when people find and
choose an interest of their own. This engagement continues over a long time and includes development and learning. The empirical
material consists of 14 learning stories written by experienced and skilled informants in folk dance and different crafts. The purpose is to illuminate the diversity
and complexity of learning and meaning the informants assign to dance or crafts. This is what we consider to be the perspective
of learning by interest. We also argue for the importance of understanding learning by interest as embedded in cultural heritage and social and cultural
changes. Theoretically, we draw on John Dewey (1913/2009; 1934/2005). Learning folk dance or crafts is largely a question of learning by doing, which makes experience important. The interest and effort involved can in our interpretation be understood as experiences where expressions of commitment are embedded. The empirical analysis highlights three emphases in this illumination of the learning process. The first considers
the individual development of skill in relation to broadened learning of collective tasks. The second perspective focuses
on the interplay between learning in a life course and significant learning experiences. The third concerns the interplay
between personal meaning and craftsmanship. In sum, this paper contributes to the understanding of learning by interest as
a useful concept. In the final discussion we expand our perspective since the contrast is obvious between learning by interest
and interpretations of the contemporary society, where individualization and lack of commitment is stressed. 相似文献
158.
Carbon encapsulated iron nanoparticles(CEINPs) with very thin shells and good core-shell structures were prepared by DC arc discharge at argon intake temperature(AIT) of 800 ℃. The results of high resolution transmission electron microscope(HRTEM), energy dispersive X-ray(EDX) spectroscope, X-ray diffraction(XRD), and X-ray photoelectron spectroscope(XPS) characterizations on the product B show that the thickness of the carbon shells of CEINPs in the product B is in the range of ca. 0.5—5.3 nm, i. e., which can be as thin as only two layers of graphite. The average diameter of the CEINPs is about 24. 7 nm. The total content of Fe element in the product B is 77.0 wt%. The saturation magnetization(Ms) and coercivity(Hc) of the product B are 107.4 emu/g and 143 Oe, respectively. The formation of the CEINPs in the product B is discussed briefly. 相似文献
159.
In this paper, silt sediment is considered to be Bingham body, which is made up of coarse and fine particles in front of a hydraulic gate. The coarse and fine particles provide friction and shear stress in the course of opening the gate. They constitute together the adhesion force of the sediment. Based on this viewpoint, this paper puts forward a formula for the effect of silt sediment on the lifting force. The formula includes gate weight, down-suction force, sealing rubber friction, plus-weight, water-column pressure, plus-silted-sediment weight and rolling (or sliding)-bearing friction. Finally, the verification results show that the formula has certain reliability and the calculation accuracy can meet the need of practical engineering. 相似文献
160.
A neuro-space mapping(Neuro-SM) for modeling heterojunction bipolar transistor(HBT) is presented, which can automatically modify the input signals of the given model by neural network. The novel Neuro-SM formulations for DC and small-signal simulation are proposed to obtain the mapping network. Simulation results show that the errors between Neuro-SM models and the accurate data are less than 1%, demonstrating that the accurcy of the proposed method is higher than those of the existing models. 相似文献