Driving Individuals’ Subjective Wellbeing in Virtual Communities through Interpersonal and Impersonal Mechanisms

In this study, we integrate different research streams—attachment, social identity, and organizational citizenship behavior—to have a better understanding of determinants of individual subjective wellbeing in the context of a virtual community (VC). Attachment is an emotion-laden, target-specific bond between a person and a specific object. Attachment is an important predictor of citizenship behavior, and therefore an important aspect to understand and to enhance in order to promote citizenship behavior. We identify two broad categories of virtual community citizenship behavior: citizenship behaviors directed toward benefitting other individuals (VCCBI), and citizenship behaviors directed toward benefitting the VC (VCCBC). We also identify two distinct attachments: emotional bonds among community members and emotional bonds to the community identity. This study proposes a dual attachment model in which subjective wellbeing is driven mainly by two mechanisms: (1) the interpersonal-based mechanism which relates common bond attachment to VCCBI and subjective wellbeing, and (2) the impersonal-based mechanism which relates common identity attachment to VCCBC and subjective wellbeing. In order to understand the two proposed mechanisms, the research model was tested with data collected from members of a VC

Exploring Individuals’ Loyalty To Online Support Groups From the Perspective Of Social Support

Prior research indicates that social support allows individuals to have additional skills to handle stresses, enhance self-esteem, and increase psychological well-being. Online social networks have become an emerging and important source of social support. However, little research has been done to explore how IT usage may improve the well-being and life quality of individuals, especially patients. Little research has been done to empirically examine individuals’ loyalty toward online social groups from the perspective of social support. This study aims to develop an integrated research model to the impact of online social support on psychological well-being and group identification, and individuals’ subsequent loyalty toward online social groups. Online social support group was operationalized as a second-order construct with four components: informational, emotional, esteem, and network supports. Data collected from 537 users of online support groups for mothers in Taiwan provide strong support for the research model. The results indicate that online social support is positively associated with psychological well-being and group identification, which in turn have a positive effect on moms’ loyalty toward online social groups. Implications for theory and practice and suggestions for future research are provided

Predicting the suitability of lateritic soil type for low cost sustainable housing with image recognition and machine learning techniques

From a sustainability point of view, laterites-compressed earth bricks (LCEB) are a promising substitute for building structures in place of the conventional concrete masonry units. On the other hand, techniques for identifying and classifying laterites soil for compressed earth bricks (CEB) production are still relying on direct human expertise or ‘experts’. Human experts exploit direct visual inspection and other basic senses such as smelling, touching or nibbling to generate a form of binomial classification, i.e. suitable or unsuitable. The source of predictive power is otherwise supposed to be found in color, scent, texture or combinations of these. Lack of clarity regarding the actual method and the possible explanatory mechanisms lead to 1) difficulties to train other people into the skills and 2) might also add to apathy to using CEB masonry units for housing. Here we systematize the selection method of experts. We chose imaging analysis techniques based on 1) easiness in image acquisition (Digital Camera) and 2) availability of machine learning and statistical techniques. We find that most of the predictive power of the ‘expert’ can be packed into visual inspection by demonstrating that with image analysis alone we get a 98% match. This makes it practically unnecessary the study of any other ‘expert’ skills and provides a method to alleviate the housing problems dealing with material construction in the developing world

Experimental procedures for precision measurements of the Casimir force with an Atomic Force Microscope

Experimental methods and procedures required for precision measurements of the Casimir force are presented. In particular, the best practices for obtaining stable cantilevers, calibration of the cantilever, correction of thermal and mechanical drift, measuring the contact separation, sphere radius and the roughness are discussed.Comment: 14 pages, 7 figure

Direct Measurement of the Magnitude of van der Waals interaction of Single and Multilayer Graphene

Vertical stacking of monolayers via van der Waals assembly is an emerging field that opens promising routes toward engineering physical properties of two-dimensional (2D) materials. Industrial exploitation of these engineering heterostructures as robust functional materials still requires bounding their measured properties so to enhance theoretical tractability and assist in experimental designs. Specifically, the short-range attractive van der Waals forces are responsible for the adhesion of chemically inert components and are recognized to play a dominant role in the functionality of these structures. Here we reliably quantify the the strength of van der Waals forces in terms of an effective Hamaker parameter for CVD-grown graphene and show how it scales by a factor of two or three from single to multiple layers on standard supporting surfaces such as copper or silicon oxide. Furthermore, direct measurements on freestanding graphene provide the means to discern the interplay between the van der Waals potential of graphene and its supporting substrate. Our results demonstrated that the underlying substrates could enhance or reduce the van der Waals force of graphene surfaces, and its consequences are explained in terms of a Lifshitz theory-based analytical model

Granger causal connectivity dissociates navigation networks that subserve allocentric and egocentric path integration

Studies on spatial navigation demonstrate a significant role of the retrosplenial complex (RSC) in the transformation of egocentric and allocentric information into complementary spatial reference frames (SRFs). The tight anatomical connections of the RSC with a wide range of other cortical regions processing spatial information support its vital role within the human navigation network. To better understand how different areas of the navigational network interact, we investigated the dynamic causal interactions of brain regions involved in solving a virtual navigation task. EEG signals were decomposed by independent component analysis (ICA) and subsequently examined for information flow between clusters of independent components (ICs) using direct short-time directed transfer function (sdDTF). The results revealed information flow between the anterior cingulate cortex and the left prefrontal cortex in the theta (4-7 Hz) frequency band and between the prefrontal, motor, parietal, and occipital cortices as well as the RSC in the alpha (8-13 Hz) frequency band. When participants prefered to use distinct reference frames (egocentric vs. allocentric) during navigation was considered, a dominant occipito-parieto-RSC network was identified in allocentric navigators. These results are in line with the assumption that the RSC, parietal, and occipital cortices are involved in transforming egocentric visual-spatial information into an allocentric reference frame. Moreover, the RSC demonstrated the strongest causal flow during changes in orientation, suggesting that this structure directly provides information on heading changes in humans

Necrotizing fasciitis in liver cirrhosis

SummaryBackgroundNecrotizing fasciitis (NF) is associated with a high mortality rate. Hepatitis is endemic in Taiwan, and liver cirrhosis is associated with the development of NF. The characteristics of these patients, however, have not been well documented or the predictors of mortality clearly identified. The purpose of this study is to identify predictors of mortality in patients with liver cirrhosis and necrotizing fasciitis.MethodsThis study was conducted at the Chi-Mei Medical Center in southern Taiwan. Demographic data, clinical characteristics, and the microorganisms responsible for NF in patients with liver cirrhosis were recorded. To identify independent predictors associated with mortality, univariate analysis followed by multivariate logistic regression modeling was performed.ResultsDuring the period 2003–2011, a total of 55 patients with liver cirrhosis and NF were treated at the Chi-Mei Medical Center. Most patients had infections by monomicrobial Gram-negative bacilli. Univariate analysis revealed that severity of liver cirrhosis, shock, band polymorphonuclear neutrophil (>10%), international normalized ratio (>1.5), serum creatinine (>2.0 mg/dL), serum albumin (<2.5 g/dL), and activated partial thromboplastin time (>60 seconds) were significantly associated with mortality. However, multivariate logistic regression analysis revealed that serum albumin of <2.5 g/dL was the only independent predictor of mortality in patients with liver cirrhosis and NF.ConclusionNF in the vast majority of cirrhotic patients was caused by Gram-negative bacilli. Hypoalbuminemia (serum albumin <2.5 g/dL) was associated with mortality in patients with liver cirrhosis and NF. Further studies are needed to assess whether resuscitation with albumin-containing solutions lowers the mortality rate in such patients

High-Frequency Sea Level Variations Observed by GPS Buoys Using Precise Point Positioning Technique

In this study, sea level variation observed by a 1-Hz Global Positioning System (GPS) buoy system is verified by comparing with tide gauge records and is decomposed to reveal high-frequency signals that cannot be detected from 6-minute tide gauge records. Compared to tide gauges traditionally used to monitor sea level changes and affected by land motion, GPS buoys provide high-frequency geocentric measurements of sea level variations. Data from five GPS buoy campaigns near a tide gauge at Anping, Tainan, Taiwan, were processed using the Precise Point Positioning (PPP) technique with four different satellite orbit products from the International GNSS Service (IGS). The GPS buoy data were also processed by a differential GPS (DGPS) method that needs an additional GPS receiver as a reference station and the accuracy of the solution depends on the baseline length. The computation shows the average Root Mean Square Error (RMSE) difference of the GPS buoy using DGPS and tide gauge records is around 3 - 5 cm. When using the aforementioned IGS orbit products for the buoy derived by PPP, its average RMSE differences are 5 - 8 cm, 8 - 13 cm, decimeter level, and decimeter-meter level, respectively, so the accuracy of the solution derived by PPP highly depends on the accuracy of IGS orbit products. Therefore, the result indicates that the accuracy of a GPS buoy using PPP has the potential to measure the sea surface variations to several cm. Finally, high-frequency sea level signals with periods of a few seconds to a day can be successfully detected in GPS buoy observations using the Ensemble Empirical Mode Decomposition (EMD) method and are identified as waves, meteotsunamis, and tides

Oxidized-monolayer Tunneling Barrier for Strong Fermi-level Depinning in Layered InSe Transistors

In 2D-semiconductor-based field-effect transistors and optoelectronic devices, metal-semiconductor junctions are one of the crucial factors determining device performance. The Fermi-level (FL) pinning effect, which commonly caused by interfacial gap states, severely limits the tunability of junction characteristics, including barrier height and contact resistance. A tunneling contact scheme has been suggested to address the FL pinning issue in metal-2D-semiconductor junctions, whereas the experimental realization is still elusive. Here, we show that an oxidized-monolayer-enabled tunneling barrier can realize a pronounced FL depinning in indium selenide (InSe) transistors, exhibiting a large pinning factor of 0.5 and a highly modulated Schottky barrier height. The FL depinning can be attributed to the suppression of metal- and disorder-induced gap states as a result of the high-quality tunneling contacts. Structural characterizations indicate uniform and atomically thin surface oxidation layer inherent from nature of van der Waals materials and atomically sharp oxide-2D-semiconductor interfaces. Moreover, by effectively lowering the Schottky barrier height, we achieve an electron mobility of 2160 cm$^2$/Vs and a contact barrier of 65 meV in two-terminal InSe transistors. The realization of strong FL depinning in high-mobility InSe transistors with the oxidized monolayer presents a viable strategy to exploit layered semiconductors in contact engineering for advanced electronics and optoelectronics