Four-part differential leukocyte count using μflow cytometer

This paper reports the four-part differential leukocyte count (DLC) of human blood using a MEMS microflow (μflow) cytometer. It is achieved with a two-color laser-induced fluorescence (LIF) detection scheme. Four types of leukocytes including neutrophils, eosinophils, lymphocytes and monocytes are identified in blood samples, which are stained by fluorescein isothiocyanate (FITC) and propidium iodide (PI). The DLC results show good correlation with the count from a commercial hematology analyzer. The whole system is also implemented into a portable instrument for space application

Thermal Blood Clot Formation and use in Microfluidic Device Valving Applications

The present invention provides a method of forming a blood-clot microvalve by heating blood in a capillary tube of a microfluidic device. Also described are methods of modulating liquid flow in a capillary tube by forming and removing a blood-clot microvalve

Blood Cell Count On-a-Chip

White blood cell (WBC) count is one of the most frequently ordered clinical tests in hospitals. There are five types of WBCs in the circulating blood, including lymphocyte, monocyte, neutrophil, eosinophil and basophil. The WBC count test enumerates not only the total number of WBCs in per volume blood, but also the percentage of each WBC type. A portable instrument for the WBC count test is currently in demand by the NASA human spaceflight, and also by the on-earth telemedicine application. However, the commercially available tests do not meet the requirement of the portable applications, because of their large instrument size and the large reagent volume consumed per test. This study describes the development of a WBC count technology optimized for portable applications. First, a sheathless microfluidic cytometer is developed for WBC count. This technology consumes only a small amount of blood (5 microlitre) and a minimal volume of reagents (50 microlitre). Second, fluorescent dye assays are developed for the WBC differential count by measuring fluorescent emissions on the microfluidic cytometer. Based on this technology, a portable instrument is built with high test accuracy (maximum error less than 10%). Furthermore, this study explores two key components for future integrating this technology into a self-contained chip. First, a microvalve actuated by thermal blood clogging is developed. This valve has a simple structure suitable for on-chip integration. Second, a micromixer is used to demonstrate the staining of blood with dye assays, and the following fluorescent detection of WBCs on the cytometer.</p

PROSOCIAL BEHAVIOR IN ENVY SCENARIOS

We investigated prosocial behavior in different envy conditions. Participants (N = 118) responded to partners&#39; requests for help after taking part in either a control scenario or scenarios where they felt that their partner was envious of them based on their performance (input), a reward (output), or both (input-output). Results showed significantly different levels of prosocial behavior, with this being highest in the output envy scenario and lowest in the input-output envy scenario. Effects of benign and malicious envy were also assessed across scenarios. In the input and output scenarios, malicious envy positively predicted prosocial behaviors and benign envy negatively predicted prosocial behaviors, whereas the opposite was true in the input-output scenario. Our results imply that employees experiencing benign envy can be motivated to improve their own abilities and performance, whereas perceiving malicious envy is likely to elicit prosocial behavior by the envied person toward envious employees.</p

Trait Depression and Subjective Well-Being: The Chain Mediating Role of Community Feeling and Self-Compassion

Although subjective well-being has been widely discussed as being one of the important indicators of clinical depression, few studies have explored how it relates to trait depression. In particular, increasing the number of positive experiences has long been a potential goal for depression-related clinical interventions, but the mechanisms by which such interventions work in countering depression have been poorly studied. Grounded in the cognitive theory of depression, the current study aimed to address this specific gap by testing the mediating effects of community feeling and self-compassion between trait depression and subjective well-being. A survey of 783 college students found that trait depression was not only able to directly and negatively predict individual subjective well-being but also indirectly predict individual subjective well-being through the mediating role of community feeling and self-compassion alone and through the chain mediating role of self-compassion from community feeling. These findings reveal the internal mechanisms of trait depression that, to some extent, impede subjective well-being and offer certain guiding significance for the self-regulation of interventions for clinical and non-clinical individuals with trait depression

Four-part leukocyte differential count based on sheathless microflow cytometer and fluorescent dye assay

Leukocyte differential count is one of the most frequently ordered clinical tests in hospitals. This paper reports a point-of-care test for the leukocyte count by using a microflow cytometer and a fluorescent dye assay. The dye assay relied on fluorescent detection alone to count leukocytes in blood and to identify leukocyte subtypes. By combining the fluorescent assay with a sheathless microflow design, the proposed method achieved a minimal sample volume by eliminating excessive dilution and sheath flow. In this paper, a four-part leukocyte differential count including lymphocyte, monocyte, neutrophil and eosinophil was demonstrated, and the whole test consumed only a small amount of blood (5 μL) and reagents (68 μL in total). The merits of minimal sample volume, long reagent shelf life and portable instrument made this method optimal for point-of-care applications

Lack of Cross-Modal Effects in Dual-Modality Implicit Statistical Learning

A current controversy in the area of implicit statistical learning (ISL) is whether this process consists of a single, central mechanism or multiple modality-specific ones. To provide insight into this question, the current study involved three ISL experiments to explore whether multimodal input sources are processed separately in each modality or are integrated together across modalities. In Experiment 1, visual and auditory ISL were measured under unimodal conditions, with the results providing a baseline level of learning for subsequent experiments. Visual and auditory sequences were presented separately, and the underlying grammar used for both modalities was the same. In Experiment 2, visual and auditory sequences were presented simultaneously with each modality using the same artificial grammar to investigate whether redundant multisensory information would result in a facilitative effect (i.e., increased learning) compared to the baseline. In Experiment 3, visual and auditory sequences were again presented simultaneously but this time with each modality employing different artificial grammars to investigate whether an interference effect (i.e., decreased learning) would be observed compared to the baseline. Results showed that there was neither a facilitative learning effect in Experiment 2 nor an interference effect in Experiment 3. These findings suggest that participants were able to track simultaneously and independently two sets of sequential regularities under dual-modality conditions. These findings are consistent with the theories that posit the existence of multiple, modality-specific ISL mechanisms rather than a single central one