Development of a modularized seating system to actively manage interface pressure.

Pressure ulcers can be a fatal complication. Many immobile wheelchair users face this threat. Current passive and active cushions do reduce the incidence of pressure ulcers and they have different merits. We proposed an active approach to combine their advantages which is based on the concept that the interface pressure can be changed with different supporting shapes. The purpose of this paper is to verify the proposed approach. With practical applications in mind, we have developed a modular system whose support surface is composed by height-adjustable support elements. Each four-element module was self-contained and composed of force sensors, position sensors, linear actuators, signal conditioners, driving circuits, and signal processors. The modules could be chained and assembled together easily to form different-sized support surfaces. Each support element took up a 3 cm × 3 cm supporting area. The displacement resolution was less than 0.1 mm and the force sensor error was less than 1% in the 2000 g range. Each support element of the system could provide 49 N pushing force (408 mmHg over the 3 cm × 3 cm area) at a speed of 2.36 mm/s. Several verification tests were performed to assess the whole system's feasibility. Further improvements and clinical applications were discussed. In conclusion, this modularized system is capable of actively managing interface pressure in real time.

Local Magnesium Sulfate Administration Ameliorates Nociception, Peripheral Inflammation, and Spinal Sensitization in a Rat Model of Incisional Pain.

OBJECTIVE: Postoperative pain remains one of the most common complaints after surgery, and appropriate treatments are limited. METHODS: We therefore investigated the effect of the anti-nociceptive properties of magnesium sulfate (MgSO4), an N-methyl-D-aspartate (NMDA) receptor antagonist, on incision-induced postoperative pain and peripheral and central nervous system inflammation. RESULTS: We found that local MgSO4 administration dose-dependently increases paw withdrawal latency, indicating reduced peripheral postoperative pain. Furthermore, MgSO4 inhibited the expression of interleukin-1ß (IL-1ß) and inducible nitric oxide synthase (iNOS) and phosphorylation of the NMDA receptor NR1 subunit in injured paw tissue and significantly attenuated microglial and astrocytic activation in the ipsilateral lumbar spinal cord dorsal horn. CONCLUSION: Locally administered MgSO4 has potential for development as an adjunctive therapy for preventing central nociceptive sensitization.

Drops sitting on a tilted plate: receding and advancing pinning.

The wetting behavior of a liquid drop sitting on an inclined plane is investigated experimentally and theoretically. Using Surface Evolver, the numerical simulations are performed based on the liquid-induced defect model, in which only two thermodynamic parameters (solid-liquid interfacial tensions before and after wetting) are required. A drop with contact angle (CA) equal to θ is first placed on a horizontal plate, and then the plate is tilted. Two cases are studied: (i) θ is adjusted to the advancing CA (θ(a)) before tilting, and (ii) θ is adjusted to the receding CA (θ(r)) before tilting. In the first case, the uphill CA declines and the downhill CA remains unchanged upon inclination. When the tilted drop stays at rest, the pinning of the receding part of the contact line (receding pinning) and the depinning of the advancing part of the contact line (advancing depinning) are observed. The free energy analysis reveals that upon inclination, the reduction of the solid-liquid free energy dominates over the increment of the liquid-gas free energy associated with shape deformation. In the second case, the downhill CA grows and the uphill CA remains the same upon inclination. Advancing pinning and receding depinning are noted for the tilted drop at rest. The free energy analysis indicates that upon inclination, the decrease of the liquid-gas free energy compensates the increment of the solid-liquid free energy. The experimental results are in good agreement with those of simulations.

Droplet compression and relaxation by a superhydrophobic surface: contact angle hysteresis.

In this article, the contact angle hysteresis (CAH) of acrylic glass is experimentally and theoretically studied through the compression-relaxation process of droplets by using a superhydrophobic surface with negligible CAH effect. In contrast to the existing technique in which the volume of the droplet changes during the measurement of CAH, this procedure is carried out at a constant volume of the droplet. By observing the base diameter (BD) and the contact angle (CA) of the droplet during the compression-relaxation process, the wetting behavior of the droplet can be divided into two regimes, the contact line withdrawal and the contact line pinning regimes, depending on the gap thickness (H) at the end of the compression process. During the compression process, both regimes possess similar droplet behavior; the contact line will move outward and the BD will expand while the CA remains at the advancing angle. During the relaxation process, the two regimes are significantly different. In the contact line withdrawal regime, the contact line will withdraw with the CA remaining at the receding angle. In the contact line pinning regime, however, the contact line will be pinned at the final position and the CA will decline to a certain value higher than the receding angle. Furthermore, the advancing pinning behavior can also be realized through a successive compression-relaxation process. On the basis of the liquid-induced defects model, Surface Evolver simulations are performed to reproduce the behavior of the droplet during the compression-relaxation process; both contact line withdrawal and pinning regimes can also be identified. The results of the experiment and simulation agree with each other very well.

Extending Theory of Planned Behavior to Understand Service-Oriented Organizational Citizen Behavior.

The financial crisis of 2007-2008 and the COVID-19 pandemic have caused many enterprises to suffer great losses. Thus, companies have to take measures such as pays cut, furloughs, or layoffs, which caused dissatisfaction among employees and triggered labor disputes. Therefore, this study explores the service-oriented organizational citizenship behavior based on the decomposed theory of planned behavior in order to understand the behavioral intentions of employees through their mental states, job attitudes, subjective norms, and perceived behavioral control. This study conducted questionnaire surveys for employees in different industries, collected 281 valid questionnaires, and applied Structural Equation Model for the analysis. The results show: (1) employees believe organizational justice in the organization is important, and when they feel treated fairly, their job attitudes and beliefs are enhanced. (2) Employees' job attitudes and beliefs support service-oriented organizational citizenship behavior, in other words, they have positive job attitudes and beliefs and will actively provide better service to customers. (3) When employees are treated reasonably and fairly by the organization and have positive job attitudes (job satisfaction and organizational commitment) and perceived behavior control, their spontaneous service-oriented organizational citizenship behavior is stimulated, thus increasing organizational development.

Exploring the Effect of Team-Environment Fit in the Relationship Between Team Personality, Job Satisfaction, and Performance.

This study explores whether team-organization fit (T-O fit) and team-job fit (T-J fit) play a mediating role between team personality, team job satisfaction, and team performance. Conscientiousness and openness to experience are common antecedents of team personality. Additionally, T-O fit and T-J fit are derived from person-environment fit theory, which is used to discuss the interaction between team members and the environment that affects behavior. The research purpose is to understand the factors that affect job satisfaction and performance from a team perspective. This is different from previous studies based on an individual perspective. The research object of this study has 365 respondents from 81 teams in different industries, and the structural equation modeling is applied to the empirical analysis. The research results show that T-J fit has a significant mediating effect on team personality and team job satisfaction. The team job satisfaction has also a significant mediating effect on team personality and team performance. Therefore, when team members recognize their work, they work harder to achieve team job satisfaction and performance. This study suggests that companies not only pay attention to the work abilities of employees, but also understand the fit between them and their jobs.

Equilibrium phase diagram of drop-on-fiber: coexistent states and gravity effect.

Drop-on-fiber is commonly observed in daily life and is closely related to digital microfluidics. The wetting behavior of droplet-on-fiber is different from that of droplet-on-plane due to the global cylindrical shape. It is generally believed that the equilibrium geometric shape of a droplet on a fiber takes either asymmetric clam-shell or axisymmetric barrel conformation in the absence of gravity. The barrel-to-clam-shell transition is determined by the stability condition. Nonetheless, experimental observations showed that both barrel and clam-shell conformations can coexist in some situations and thus indicated the existence of the multiple stable states. In this Article, the phase diagrams of droplet-on-fiber, that is, the plots of droplet volume against contact angle, are established on the basis of the finite-element simulation (Surface Evolver). When the gravity effect is absent, there are three regimes including barrel, clam-shell, and coexistence of barrel and clam-shell. As the gravity effect is considered, there exist three regimes, including (I) downward clam-shell, (II) coexistence of barrel and clam-shell, and (III) falling-off.

Anomalous contact angle hysteresis of a captive bubble: advancing contact line pinning.

Contact angle hysteresis of a sessile drop on a substrate consists of continuous invasion of liquid phase with the advancing angle (θ(a)) and contact line pinning of liquid phase retreat until the receding angle (θ(r)) is reached. Receding pinning is generally attributed to localized defects that are more wettable than the rest of the surface. However, the defect model cannot explain advancing pinning of liquid phase invasion driven by a deflating bubble and continuous retreat of liquid phase driven by the inflating bubble. A simple thermodynamic model based on adhesion hysteresis is proposed to explain anomalous contact angle hysteresis of a captive bubble quantitatively. The adhesion model involves two solid­liquid interfacial tensions (γ(sl) > γ(sl)'). Young's equation with γ(sl) gives the advancing angle θ(a) while that with γ(sl)' due to surface rearrangement yields the receding angle θ(r). Our analytical analysis indicates that contact line pinning represents frustration in surface free energy, and the equilibrium shape corresponds to a nondifferential minimum instead of a local minimum. On the basis of our thermodynamic model, Surface Evolver simulations are performed to reproduce both advancing and receding behavior associated with a captive bubble on the acrylic glass.

Consumers' Intention to Adopt Blockchain Food Traceability Technology towards Organic Food Products.

Establishing a blockchain food traceability system (BFTS) is increasingly important and urgent to resolve the contradiction between consumers' intention regarding safe food selections and the spread of polluted foods. Using the advantages of blockchain, such as immutability, decentralization, openness, and anonymity, we can build trusted food traceability systems based on these important characteristics. With reliable information, traceability from production to sales can effectively improve food safety. In this research, multiple models, namely, the information success model (ISS) and the Theory of Planned Behavior (TPB) are formed into a conceptual integrated framework to study the intentions' influenced factors of BFTS technology for Chinese consumers to help ensure food safety and the quality of Chinese organic food products. A face-to-face questionnaire survey with 300 valid responses was analyzed by Partial Least Square from the Chinese consumers focusing on the organic food products. This study found that the attitude and perceived behavioral control qualities significantly and positively affect the usage intention in adopting BFTS, while the subjective norms are positively but not significantly correlation with the usage intention in using BFTS. The above results will inform suggestions for productors and academics along with implications to promote BFTS' usage intention.

Upregulation of RelB in the miR-122 knockout mice contributes to increased levels of proinflammatory chemokines/cytokines in the liver and macrophages.

OBJECTIVE: MicroRNA-122 (miR-122) is the most abundant miRNA in the liver and it plays an important role in regulating liver metabolism and tumor formation. Previous studies also reveal an anti-inflammatory function of miR-122; however, relatively little is known about the mechanisms by which miR-122 suppresses inflammation. This study aims to search the effect of miR-122 on proinflammatory chemokines/cytokines production in mice. METHODS: Quantitative real-time PCR, Western blot analysis, and ELISA were performed to examine gene expression. TargetScan, miRanda, and microT v3.0 were used to search for possible miR-122 target sites in the 3'-untranslated regions (3'-UTR) of candidate genes. Luciferase reporter assay and site-directed mutagenesis were applied to verify miR-122 target sequences. LPS was applied to peritoneal macrophages and mice to evaluate inflammatory response. RESULTS: The expression of proinflammatory chemokines, including Ccl2, Ccl4, Ccl20, Cxcl2, and Cxcl10, and Relb in the livers of miR-122 knockout (KO) mice was increased. We identified Relb as a direct miR-122 target. Overexpressing RelB in the mouse liver increased the expression of Ccl2, Ccl4, Ccl20, Cxcl2, and Cxcl10. Peritoneal macrophages from miR-122 KO mice had a higher level of RelB, and they showed a stronger NF-κB activation and more TNF-α and IL-6 secretion after LPS stimulation. Overexpression of RelB in a macrophage cell line augmented LPS-induced TNF-α and IL-6 production. miR-122 KO mice showed a greatly increased mortality rate and generated a stronger and lasting inflammatory response to LPS. CONCLUSIONS: Deletion of miR-122 caused an upregulation of proinflammatory chemokines and RelB in the liver. Increased RelB may contribute to increases in these chemokine in the liver. Intriguingly, deletion of miR-122 also enhanced the sensitivity of macrophages and mice to LPS. Our results reveal that reducing RelB expression is a new mechanism by which miR-122 regulates inflammation.

Stress Writing Textured Graphite Conducting Wires/Patterns in Insulating Amorphous Carbon Matrix as Interconnects.

This study reports a mechanical stress-based technique that involves scratching or imprinting to write textured graphite conducting wires/patterns in an insulating amorphous carbon matrix for potential use as interconnects in future carbonaceous circuits. With low-energy post-annealing below the temperature that is required for the thermal graphitization of amorphous carbon, the amorphous carbon phase only in the mechanically stressed regions transforms into a well aligned crystalline graphite structure with a low electrical resistivity of 420 µΩ-cm, while the surrounding amorphous carbon matrix remains insulating. Micro-Raman spectra with obvious graphitic peaks and high-resolution transmission electron microscopic observations of clear graphitic lattice verified the localized phase transformation of amorphous carbon into textured graphite exactly in the stressed regions. The stress-induced reconstruction of carbon bonds to generate oriented graphitic nuclei is believed to assist in the pseudo-self-formation of textured graphite during low-temperature post annealing.

Multiple analyses of factors related to complications in endoscopic sinus surgery.

BACKGROUND: This study was undertaken to evaluate whether endoscopic sinus surgery (ESS) with a microdebrider had an impact on complication rates, and to facilitate the determination of factors associated with complications in patients who underwent ESS at a tertiary referral center in Taiwan. METHODS: This investigation was a retrospective study and literature review. We analyzed 997 consecutive patients who underwent ESS at Mackay Memorial Hospital in Taipei, Taiwan from January 2006 through February 2010. All data including those of patient medical information, and peri- and postoperative complications were provided by the surgeons involved in patient medical care. We analyzed the complication rates using the following 10 variables by univariate analysis and multivariate logistic regression: sex, age, Lund-Mackay score, polyp grading, previous sinonasal surgery, surgeon skill, adjunctive sinonasal surgery, mesenteric type of anterior ethmoid artery, Keros skull base type, and the use of a microdebrider. RESULTS: Of the 997 patients in our study, 78 (7.8%) had complications. Major complications occurred in five patients (0.5%): two with cerebrospinal fluid rhinorrhea, one with medial rectus muscle damage, and two with retrobulbar hematoma. Minor complications were found in 73 patients (7.3%), which included 32 patients with perioperative estimated blood loss > 15% of the total estimated blood volume, 26 with lamina papyracea damage, two with orbital cellulitis, and 13 with postoperative bleeding. Univariate analysis showed that risk factors related to complication rate were advanced Lund-Mackay scores (scores 19-24), advanced polyp grading (Grades 2 and 3), inexperienced surgeon (resident), and microdebrider usage. However, multivariate analysis revealed that complication rate was linked to advanced Lund-Mackay scores (Scores 19-24), mesenteric type of anterior ethmoid artery, and inexperienced surgeon. CONCLUSION: Overall, the results of our study showed that the ESS complication rate was 7.8%, with risk factors including advanced Lund-Mackay scores (19-24, odds ratio 10.4) and inexperienced surgeon. It was also noted that ESS with a microdebrider had no impact on complication rates, although the presence of a mesenteric type of anterior ethmoid artery proved to be a protective factor.

Characterization of the psychological, physiological and EEG profile of acute betel quid intoxication in naïve subjects.

Betel quid use and abuse is wide spread in Asia but the physiological basis of intoxication and addiction are unknown. In subjects naïve to the habit of betel quid intoxication, the psychological and physiological profile of intoxication has never been reported. We compared the effect of chewing gum or chewing betel quid, and subsequent betel quid intoxication, on psychological assessment, prospective time interval estimation, numerical and character digit span, computerized 2 choice tests and mental tasks such as reading and mathematics with concurrent monitoring of ECG, EEG and face temperature in healthy, non-sleep deprived, male subjects naïve to the habit of chewing betel quid. Betel quid intoxication, dose dependently induced tachycardia (max 30 bpm) and elevated face temperature (0.7°C) (P<0.001) above the effects observed in response to chewing gum (max 12 bpm and 0.3°C) in 12 subjects. Gross behavioral indices of working memory such as numerical or character digit span in 8 subjects, or simple visual-motor performance such as reaction speed or accuracy in a two choice scenario in 8 subjects were not affected by betel quid intoxication. Betel quid intoxication strongly influenced the psychological aspects of perception such as slowing of the prospective perception of passage of a 1 minute time interval in 8 subjects (P<0.05) and perceived increased arousal (P<0.01) and perceived decreased ability to think (P<0.05) in 31 subjects. The EEG spectral profile recorded from mental states associated with open and closed eyes, and mental tasks such as reading and eyes closed mental arithmetic were significantly modified (P<0.05) relative to chewing gum by betel quid intoxication in 10 subjects. The prevalence of betel quid consumption across a range of social and work settings warrants greater investigation of this widespread but largely under researched drug.

Wetting behavior of a drop atop holes.

Superhydrophobic surfaces generally involve completely nonwetting or partially wetting roughness. Because the contact angle is closely related to the liquid-gas interfacial tension, the shape of the liquid-gas interfaces within the grooves plays a key role in determining the droplet wetting behavior. We consider a droplet with volume, V, atop holes with radius, r, and obtain the analytical expression of the bottom liquid-air shape based on surface free energy minimization. It is found that the bottom shape in terms of the interfacial angle, theta(1), depends on the hole size through V/r(3) in addition to the intrinsic contact angle, theta(*). For a given droplet volume, the smaller the hole size (r(3)/V --> 0), the more flat the interface (theta(1) --> 0). In addition, the flatness of the interface grows with reducing the intrinsic contact angle. Numerical simulations of Surface Evolver are performed to confirm our theory. Moreover, wetting experiments in which the gravity effect cannot be neglected are conducted, and the results are consistent with those by numerical simulations. Our result points out that such wall-free capillarity may be useful in extracting liquid from microfluidic device spontaneously.