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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   
174.

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.
  相似文献   
175.
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   
176.
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   
177.
Research has consistently found acute mental health treatment disparities among Asian Americans. One proposed reason for the underutilization of mental health services by Asian Americans is that available services are not culturally competent. This exploratory study presents qualitative data gathered from interviews with professional counselors who serve Asian American clients. Findings revealed significant barriers to counseling due to cultural stigma and shame, suppression of emotions, and communication gaps between clients and counselors. In response, clinicians frequently made adjustments to therapeutic approaches to accommodate the cultural beliefs and practices of clients and families. Implications for practice and research are discussed.  相似文献   
178.

Introduction:

Sample type recommended by the manufacturer for the digoxin Abbott assay is either serum collected in glass tubes or plasma (sodium heparin, lithium heparin, citrate, EDTA or oxalate as anticoagulant) collected in plastic tubes. In our hospital samples are collected in plastic tubes. Our hypothesis was that the serum sample collected in plastic serum tube can be used interchangeably with plasma sample for measurement of digoxin concentration. Our aim was verification of plastic serum tubes for determination of digoxin concentration.

Materials and methods:

Concentration of digoxin was determined simultaneously in 26 venous blood plasma (plastic Vacuette, LH Lithium heparin) and serum (plastic Vacuette, Z Serum Clot activator; both Greiner Bio-One GmbH, Kremsmünster, Austria) samples, on Abbott AxSYM analyzer using the original Abbott Digoxin III assay (Abbott, Wiesbaden, Germany). Tube comparability was assessed using the Passing Bablok regression and Bland-Altman plot.

Results:

Serum and plasma digoxin concentrations are comparable. Passing Bablok intercept (0.08 [95% CI = −0.10 to 0.20]) and slope (0.99 [95% CI = 0.92 to 1.11]) showed there is no constant or proportional error.

Conclusion:

Blood samples drawn in plastic serum tubes and plastic plasma tubes can be interchangeably used for determination of digoxin concentration.  相似文献   
179.
The term absorptive capacity (AC) describes the process of utilising external knowledge. Although firms are becoming increasingly reliant on highly skilled freelancers as a source of external knowledge, the literature on AC has not incorporated this collaboration for freelancers. In this paper, we address this research deficit in two ways: First, we argue that the ability to collaborate effectively and efficiently with freelancers plays a crucial role in the process of absorbing external knowledge. Second, we argue that the example of freelancers challenges researchers to rethink the conceptualisation of organisational boundaries within the concept of AC. Our paper is based upon previous theoretical insights and exploratory empirical data from a research project on German IT freelancers. For the practice of knowledge management, our paper elaborates upon how organisations can enhance their AC by investing in practices and routines that contribute to successful collaboration with freelancers.  相似文献   
180.
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