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161.
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   
162.
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   
163.
The Bacillus strain BH072 isolated from a honey sample showed strong antifungal activity against phytopathogen. Gene cloning test demonstrated that the strain had a tasA gene encoding an antifungal TasA protein. Although the wild strain simultaneously produced various antifungal substances, only the physicochemical property and antifungal activity of TasA protein were unclear due to the difficulty in extraction. In this study, tasA gene encoding the protein from Bacillus sp. BH072 was amplified by using the polymerase chain reaction (PCR) method and cloned into pET 28a (+) vector, and then expressed in host cells Escherichia coli BL21 (DE3). The expressed proteins were collected by centrifugation and ultrasonic treatment, and then purified by using nickel-nitrilotriacetic acid (Ni-NTA) metal affinity column and dialysis methods. The result of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) test showed that an expected protein band appeared with a size of 31 kDa. The expressed products possessed antifungal activity against the phytopathogenic indicator strain Botrytis cinerea. A genetically engineered strain tasA of E. coli was established in this study which can efficiently express Tas A protein.  相似文献   
164.
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   
165.
Phonics, fluency, and reading strategy trainings are evidence-based interventions that foster the reading skills of poor readers in primary school. The purpose of the present study was to compare differential effects of the three types of trainings on the efficiency of component processes on word, sentence, and text level immediately after the training and at a 3-month follow-up. The 235 poor readers were randomly allocated to one of the reading interventions or to a control condition. All interventions consisted of 25 sessions that were scheduled twice a week and lasted 45 min. Results indicated short-term effects of the phonics training and the strategy training on the efficiency of a broad range of word-level and sentence-level processes. None of the treatment effects persisted over the long term, indicating the need for instructional efforts to regularly practice the acquired skills after the actual training.  相似文献   
166.

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   
167.
The objective of this paper is to take an in-depth look, from a network perspective, at the role that social capital plays in improving knowledge exchange between organizations. To do this, we consider the three dimensions of social capital: the structural dimension, as measured by the position of firms bridging structural holes; the relational dimension, as gauged by the level of trust and friendship in each relationship; and the cognitive dimension, as estimated by the presence of a shared culture. We also evaluate the level of organizational and human capital present in terms of the firms in the network. Empirical evidence has been gathered from the Madrid Science Park in Spain by applying the social network analysis methodology. The results show that the three dimensions of social capital play a significant role in increasing knowledge exchange in this network, while human and organizational capital differences are only significant for a sub-sample.  相似文献   
168.
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   
169.
When the need to record and track the point of view of different actors in organizational processes becomes a key point for decision makers, a common representation of knowledge from different perspectives and a map of the situation and the decision and action needs could be useful. A methodology that easily and transparently integrates different ‘soft’ and ‘hard’ tools in a common knowledge structuring approach is proposed to deal with complexities and uncertainties in a socio-technical contest. The purpose of this paper is to show the potentialities of this methodology in a real case, in terms of organizational knowledge acquisition and structuring in a multi-actor public context, a university faculty, in relation to a radical change.  相似文献   
170.

Introduction:

There are a number of pre-analytical and analytical factors, which cause false results in the complete blood count. The present case identifies cold agglutinins as the cause for the mismatch between hematocrit and hemoglobin values.

Materials and methods:

70-year old female patient had a history of cerebrovascular diseases and rheumatoid arthritis. During routine laboratory examination, the patient had normal leukocyte and platelet counts; however, the hemoglobin (Hb: 105 g/L) and hematocrit (HCT: 0.214 L/L) results were discordant. Hemolysis, lipemia and cold agglutinin were evaluated as possible reasons for the mismatch between hematocrit and hemoglobin values.

Results:

First blood sample was slightly hemolysed. Redrawn sample without hemolysis or lipemia was analyzed but the mismatch became even more distinct (Hb: 104 g/L and HCT: 0.08 L/L). In this sample, the titration of the cold agglutinin was determined and found to be positive at 1:64 dilution ratios. After an incubation of the sample at 37°C for 2 hours, reversibility of agglutination was observed.

Conclusion:

We conclude that cold agglutinins may interfere with the analysis of erythrocyte and erythrocyte-related parameters (HCT, MCV, MCH and MCHC); however, Hb, leukocyte and platelet counts are not affected.  相似文献   
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