Normative Legitimacy in the Commercialization of Online Community Website

Many online community websites start their operation by a not-for-profit business model, which attracts a lot of users to engage in. The huge user base and heavy Internet traffic could generate revenue and wealth for the websites. When the online communities are becoming popular, entrepreneurs of the online community website may hope to commercialize the online community. Nevertheless, some of community participants are against the commercialization of the online community website, since they regard that the property of online community is belonged to users rather than website owners. Users may challenge the legitimacy in the commercialization process of online community, and argue that the online community should be owned by the public rather than by a company since the enormous community participants put effort in it and make the website a popular one. This study used two case studies of online communities to explain the normative legitimate issues in the entrepreneurship of online community

Development of a Partial Proportional Odds Model for Pedestrian Injury Severity at Intersections

Pedestrian injury in crashes at intersections often results from complex interaction among various factors. The factor identification is a critical task for understanding the causes and improving the pedestrian safety. A total of 2,614 crash records at signalized and non-signalized intersections were applied. A Partial Proportional Odds (PPO) model was developed to examine the factors influencing Pedestrian Injury Severity (PIS) because it can accommodate the ordered response nature of injury severity. An elasticity analysis was conducted to quantify the marginal effects of contributing factors on the likelihood of PIS. For signalized intersections, seven explanatory variables significantly affect the likelihood of PIS, in which five explanatory variables violate the Proportional Odds Assumption (POA). Local driver, truck, holiday, clear weather, and hit-and-run lead to higher likelihood of severer PIS. For non-signalized intersections, six explanatory variables were found significant to the PIS, in which three explanatory variables violate the POA. Young and adult drivers, senior pedestrian, bus/van, divided road, holiday, and darkness tend to increase the likelihood of severer PIS. The vehicles of large size and heavy weight (e.g. truck, bus/van) are significant factors to the PIS at both signalized and non-signalized intersections. The proposed PPO model has demonstrated its effectiveness in identifying the effects of contributing factors on the PIS.</p

Effects of fluid resuscitation on cerebral tissue oxygenation changes in a piglet model of hemorrhagic shock

AbstractBackgroundAcute blood loss linked to severe hypovolemia and hemorrhagic shock is a critical condition in pediatric intensive care. This study was to investigate the role of various fluid resuscitation approaches to cerebral tissue oxygenation using a piglet model of hemorrhagic shock.MethodsThirty piglets received blood removal to induce hemorrhagic shock, and then were randomly assigned to a control group (no treatment), a control-normal saline (NS) group (treated with bolus normal saline 10mL/kg only), or one of three treatment groups treated with 15mL/kg/dose fluid every 30min with either whole blood (WB), lactated Ringer’s solution (LR), or NS in addition to an initial bolus of saline. The piglets’ physiological profiles, arterial blood gases, and regional cerebral oxygen saturation (rScO2) levels were recorded, fractional tissue oxygen extraction was calculated, and blood hemoglobin levels were measured.ResultsThe results showed that no matter whether treated with only one dose of bolus NS (control-NS group) or with extra WB, LR, or NS, all the treated animals had a significantly higher survival rate, mean arterial blood pressure (MAP), arterial oxygen tension, arterial oxygen saturation, and rScO2 than the control group (p<0.05). Animals treated with WB all survived the full experimental period, and their hemoglobin levels, MAP, and rScO2 were the highest comparing to all other groups (p<0.05).ConclusionEffective resuscitation using a high concentration of inspired oxygen and adequate fluid infusion, either as a single-dose bolus of NS or combining this with a subsequent transfusion of WB, LR, or NS, helped to stabilize the cardiovascular condition of the tested young subjects and improved cerebral tissue oxygenation over the emergent first four hours. Furthermore, WB was the best fluid choice when used in addition to the bolus NS challenge for maintaining better brain tissue oxygenation when treating hemorrhagic shock

Predicting Bus Travel Time with Hybrid Incomplete Data – A Deep Learning Approach

The application of predicting bus travel time with real-time information, including Global Positioning System (GPS) and Electronic Smart Card (ESC) data is effective to advance the level of service by reducing wait time and improving schedule adherence. However, missing information in the data stream is inevitable for various reasons, which may seriously affect prediction accuracy. To address this problem, this research proposes a Long Short-Term Memory (LSTM) model to predict bus travel time, considering incomplete data. To improve the model performance in terms of accuracy and efficiency, a Genetic Algorithm (GA) is developed and applied to optimise hyperparameters of the LSTM model. The model performance is assessed by simulation and real-world data. The results suggest that the proposed approach with hybrid data outperforms the approaches with ESC and GPS data individually. With GA, the proposed model outperforms the traditional one in terms of lower Root Mean Square Error (RMSE). The prediction accuracy with various combinations of ESC and GPS data is assessed. The results can serve as a guideline for transit agencies to deploy GPS devices in a bus fleet considering the market penetration of ESC

Simulation-Based Estimates of Delays at Freeway

ABSTRACT Work zone related traffic delay is an important cost component on freeways with maintenance activities. This study demonstrates that delays are always underestimated by using the deterministic queuing theory. Computer simulation is a valuable approach of estimating delay under variety of existing and future conditions. However, a single simulation run, which can be quiet costly in terms of both computer and analyst time

Methionine Adenosyltransferase I/III Deficiency in Portugal: High Frequency of a Dominantly Inherited Form in a Small Area of Douro High Lands

Methionine adenosyltransferase deficienc(MAT I/III deficiency) is an inborn error of metabolism resulting in isolated hypermethioninemia, and usually inherited as an autosomal recessive trait, although a dominant form has been reported in several families. During the last 6 years, approximately 520,000 newborns were screened in the Portuguese Newborn Screening Laboratory by MS/MS, and 21 cases of persistent hypermethioninemia were found. One case was confirmed to be a deficiency of cystathionine b-synthase and 20 cases were confirmed by MAT1A gene analysis to have an elevation of methionine due to MAT I/III deficiency, which indicates an incidence for this condition of 1/26,000. Twelve of the MAT I/III deficient newborns, belonging to 11 families, were identified in the northern region of Portugal and sent to the same treatment center, where they are under follow-up. Clinical, biochemical, and genetic characteristics of individuals from these 11 families are presented. Plasma methionine and homocysteine concentrations were found to be moderately increased in all newborns, and molecular analysis revealed that they all were heterozygous for R264H mutation. Normal growth,development, and neurological examination were observed in all cases, and cerebral MRI performed in six cases revealed myelination abnormalities in one case. Plasma methionine concentration for all 12 cases was always below 300 mM, and they are all on a normal diet for their age

Extremely long quasiparticle spin lifetimes in superconducting aluminium using MgO tunnel spin injectors

There has been an intense search in recent years for long-lived spin-polarized carriers for spintronic and quantum-computing devices. Here we report that spin polarized quasi-particles in superconducting aluminum layers have surprisingly long spin-lifetimes, nearly a million times longer than in their normal state. The lifetime is determined from the suppression of the aluminum's superconductivity resulting from the accumulation of spin polarized carriers in the aluminum layer using tunnel spin injectors. A Hanle effect, observed in the presence of small in-plane orthogonal fields, is shown to be quantitatively consistent with the presence of long-lived spin polarized quasi-particles. Our experiments show that the superconducting state can be significantly modified by small electric currents, much smaller than the critical current, which is potentially useful for devices involving superconducting qubits