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Liquid films on wettable solid surfaces can be disturbed to dewet when low surface tension liquids or surfactants are added because the surface tension difference gives rise to stresses on the film interface. Here we consider an alcohol drop placed above a thin aqueous film, which punctures a hole in the film starting from underneath the alcohol drop. Such film dewetting is attributed to the Marangoni effects caused by the spatial gradient of alcohol vapour concentration. We measure the liquid–gas interfacial tension of aqueous liquids rapidly responding to the surrounding isopropyl alcohol vapour concentration, and observe evolution of the film morphology consisting of central hole, fringe film, thinning region and bulk. We construct scaling laws to predict the dewetting rates of the film by considering the Marangoni stress, viscous shear stress and evaporation. It is shown that our experiments are consistent with our theory.
We analysed optimal nutrient levels using linear programming (LP) to reveal nutritional shortcomings of Korean dine-out meals and to stress the importance of fruits and dairy products for maintaining a healthy diet.
LP models that minimize deviation from recommended nutrient values were formulated to analyse deficiency or excess of nutrients under the best situation.
Korean dine-out menus and nutritional information were taken from the nutrient composition tables for dine-out menus developed by the Ministry of Food and Drug Safety and the nutrient database from Computerized Analysis Program. Acceptable macronutrient distribution ranges of macronutrients such as carbohydrate, protein and fat, and recommended intake levels for energy, vitamins, minerals and cholesterol, by sex, were based on the Dietary Reference Intake for Koreans aged 30–49 years.
Optimization was performed on selecting the optimal Korean meal combination.
LP optimization models showed that it is unlikely to satisfy all nutrient recommendations with any combination of dine-out menus. Specifically, meal combinations of Korean dine-out menus had high levels of Na and cholesterol and low levels of vitamins and minerals. Four formulations were considered to compare the effects of controlling Na and including fruit and dairy products. The unbalanced diet was resolved with extra consumption of fruits and dairy products.
The best meal combination in dine-out menus, even though the proportion and pairing of menus may be unrealistic, is not healthy, and thus one should consume fruits and dairy products to maintain a balanced diet.
We propose a new method for preparing atom probe tomography specimens from nanoparticles using a fusible bismuth–indium–tin alloy as an embedding medium. Iron nanoparticles synthesized by the sodium borohydride reduction method were chosen as a model system. The as-synthesized iron nanoparticles were embedded within the fusible alloy using focused ion beam milling and ion-milled to needle-shaped atom probe specimens under cryogenic conditions. An atom probe analysis revealed boron atoms in a detected iron nanoparticle, indicating that boron from the sodium borohydride reductant was incorporated into the nanoparticle during its synthesis.
Patent foramen ovale (PFO) is an open hole between the right and left upper chambers of the heart. It may increase the risk of stroke, so closure of the hole is considered a secondary prevention in patients who have experienced cryptogenic stroke. Recent evidence has been published on the effectiveness of PFO closure, including a publicly funded prospective study on the effectiveness of PFO closure for preventing recurrent stroke or transient ischemic attack in selected Korean patients who have experienced cryptogenic stroke. The objective of this study was to examine the cost-effectiveness of PFO closure using this recent evidence.
Available clinical data from the aforementioned Korean prospective study and other recent multicenter trials funded by public bodies were used. The cost data were obtained from the current Korean National Health Insurance fee schedule. Utility data were extracted from local research on stroke patients. A cost-effectiveness analysis, based on a 20-year Markov model, was conducted using these data to compare PFO closure plus antiplatelet therapy with oral anticoagulants alone.
The initial analysis showed that PFO plus antiplatelet therapy costs KRW 7.13 million (USD 6,547) more than oral anticoagulants alone but has a higher utility of 1.3 quality-adjusted life-years (QALYs) per patient, which corresponds to an incremental cost-effectiveness ratio (ICER) of KRW 5.6 million (USD 5,142) per QALY. The implicit Korean ICER threshold is KRW 25 million (USD 22,955) for non-cancer drugs, so it seems that PFO plus antiplatelet therapy is cost effective in the Korean setting.
Since this study used some transition probabilities from foreign sources, the results may not be completely transferable to the Korean setting. However, this is the best available evidence so far in Korea for the economic evaluation of the PFO closure procedure. Therefore, use of PFO closure in carefully selected patients with a history of cryptogenic stroke may benefit the public payer in Korea.
This study of loneliness across adult lifespan examined its associations with sociodemographics, mental health (positive and negative psychological states and traits), subjective cognitive complaints, and physical functioning.
Analysis of cross-sectional data
340 community-dwelling adults in San Diego, California, mean age 62 (SD = 18) years, range 27–101 years, who participated in three community-based studies.
Loneliness measures included UCLA Loneliness Scale Version 3 (UCLA-3), 4-item Patient-Reported Outcomes Measurement Information System (PROMIS) Social Isolation Scale, and a single-item measure from the Center for Epidemiologic Studies Depression (CESD) scale. Other measures included the San Diego Wisdom Scale (SD-WISE) and Medical Outcomes Survey- Short form 36.
Seventy-six percent of subjects had moderate-high levels of loneliness on UCLA-3, using standardized cut-points. Loneliness was correlated with worse mental health and inversely with positive psychological states/traits. Even moderate severity of loneliness was associated with worse mental and physical functioning. Loneliness severity and age had a complex relationship, with increased loneliness in the late-20s, mid-50s, and late-80s. There were no sex differences in loneliness prevalence, severity, and age relationships. The best-fit multiple regression model accounted for 45% of the variance in UCLA-3 scores, and three factors emerged with small-medium effect sizes: wisdom, living alone and mental well-being.
The alarmingly high prevalence of loneliness and its association with worse health-related measures underscore major challenges for society. The non-linear age-loneliness severity relationship deserves further study. The strong negative association of wisdom with loneliness highlights the potentially critical role of wisdom as a target for psychosocial/behavioral interventions to reduce loneliness. Building a wiser society may help us develop a more connected, less lonely, and happier society.
Point-of-Care Ultrasound (POCUS) has become an important diagnostic tool for hospital-based clinicians. This study assesses the role of POCUS at Pemberton Music Festival 2016 (Pemberton, British Columbia [BC], Canada), a remote mass gathering where physicians face limited resources, complex disposition decisions, and a dynamic clinical environment.
This study prospectively evaluated the impact of POCUS on patient diagnosis, management, and disposition based on the self-report of the study physicians. The authors hypothesized that having ultrasound available for use would aid in diagnostic and management decisions and would reduce the need to transfer patients off-site to other health care facilities, reducing impact on the acute health services in the host community.
A handheld ultrasound was available for use by physicians in the main medical tent. All participating physicians self-reported their training and comfort using POCUS. After each POCUS scan, physicians completed a survey and recorded the indication for use, scans performed, and impact on patient diagnosis, management, and disposition.
In total, POCUS was used on 28 of the 686 patients treated in the main medical tent; POCUS was reported to narrow the differential diagnosis in 64% of cases and altered the working diagnosis in 21% of cases. Its use changed the management plan in 39% of patients. Its use was reported to reduce the burden on broader health care resource utilization in 46% of cases and prevented ambulance transport off-site in 32% of cases (nine cases in total). This corresponded to an absolute risk reduction of 1.3% for the percentage of patients transferred to hospital (PPTH; relative risk reduction of 53%).
Physicians reported that POCUS improved the diagnosis, management, and disposition of select patients at a remote, multi-day music festival. Also, POCUS reduced ambulance transfers off-site and reduced the perceived burden on broader health care utilization.
PragerR, SedgwickC, LundA, KimD, HoB, StachuraM, GutmanS. Prospective Evaluation of Point-of-Care Ultrasound at a Remote, Multi-Day Music Festival. Prehosp Disaster Med. 2018;33(5):484–489.
Bismuth vanadate (BiVO4) is regarded as a viable material for water oxidation due to various benefits such as visible light absorption, low production cost, and resistance to photocorrosion. Recently, numerous attempts have been adopted to improve the performance of BiVO4. In this work, we highlight the important strategies that have been made for improving the performance of the photoanode material, such as fabricating nanostructured electrode, controlling reacting facet, stacking with other materials, utilizing plasmonics, loading co-catalyst, and controlling the interfacial band bending with ferroelectrics. Taking advantage of the strategies, highly efficient BiVO4 photoelectrodes could be demonstrated. Finally, we discuss the perspective of BiVO4-based photoanodes.
To verify the validity of a semiautomated surgical site infection (SSI) surveillance system using electronic screening algorithms in 38 categories of surgery.
A cohort study for validation of semiautomated SSI surveillance system using screening algorithms.
A 1,989-bed tertiary-care referral center in Seoul, Republic of Korea.
A dataset of 40,516 surgical procedures in 38 categories stored in the conventional SSI surveillance registry at the Samsung Medical Center between January 2013 and December 2014 was used as the reference standard. In the semiautomated surveillance system, electronic screening algorithms flagged cases meeting at least 1 of 3 criteria: antibiotic prescription, microbial culture, and infectious disease consultation. Flagged cases were audited by infection preventionists. Analyses of sensitivity, specificity, and positive predictive value (PPV) were conducted for the semiautomated surveillance system, and its effect on reducing the workload for chart review was evaluated.
A total of 575 SSI events (1·42%) were identified by conventional SSI surveillance. The sensitivity of the semiautomated SSI surveillance was 96·7%, and the PPV of the screening algorithms alone was 4·1%. Semiautomated SSI surveillance reduced the chart review workload of the infection preventionists from 1,283 to 482 person hours per year (a 62·4% decrease).
Compared to conventional surveillance, semiautomated surveillance using electronic screening algorithms followed by chart review of selected cases can provide high-validity surveillance results and can significantly reduce the workload of infection preventionists.
In the past, alliance portfolio configuration (APC) studies concentrated mostly on the direct alliances or partners of a focal firm. However, a focal firm is also influenced by indirect alliances or partners. This study endeavors to focus on this aspect of APC. It contributes to APC research by extending the scope to three degrees from a focal firm. To assess the effects of extended APCs, 186 3-year window snapshots were created of the extended APCs of 31 Korean bio-pharmaceutical firms. These snapshots range from 2007 to 2014. The effects of structure (density), size (number of alliances and partners), and relationships to firm innovation were measured using the two-step generalized method of moments estimates. The results show that structural sparseness and larger-sized extended APCs are more favorable conditions for innovation, and that structural sparseness and size have a positive relationship to innovation performance.
Introduction: Patients with Heart failure (HF) experience frequent decompensation necessitating multiple emergency department (ED) visits and hospitalizations. If patients are able to receive timely interventions and optimize self-management, recurrent ED visits may be reduced. In this feasibility study, we piloted the application of home telemonitoring to support the discharge of HF patients from hospital to home. We hypothesized that TEC4Home would decrease ED revisits and hospital admissions and improve patient health outcomes. Methods: Upon discharge from the ED or hospital, patients with HF received a blood pressure cuff, weight scale, pulse oximeter, and a touchscreen tablet. Participants submitted measurements and answered questions on the tablet about their HF symptoms daily for 60 days. Data were reviewed by a monitoring nurse. From November 2016 to July 2017, 69 participants were recruited from Vancouver General Hospital (VGH), St. Pauls Hospital (SPH) and Kelowna General Hospital (KGH). Participants completed pre-surveys at enrollement and post-surveys 30 days after monitoring finished. Administrative data related to ED visits and hospital admissions were reviewed. Interviews were conducted with the monitoring nurses to assess the impact of monitoring on patient health outcomes. Results: A preliminary analysis was conducted on a subsample of participants (n=22) enrolled across all 3 sites by March 31, 2017. At VGH and SPH (n=14), 25% fewer patients required an ED visit in the post-survey reporting compared to pre-survey. During the monitoring period, the monitoring nurse observed seven likely avoided ED admissions due to early intervention. In total, admissions were reduced by 20% and total hospital length of stay reduced by 69%. At KGH (n=8), 43% fewer patients required an ED visit in the post-survey reporting compared to the pre-survey. Hospital admissions were reduced by 20% and total hospital length of stay reduced by 50%. Overall, TEC4Home participants from all sites showed a significant improvement in health-related quality of life and in self-care behaviour pre- to 90 days post-monitoring. A full analysis of the 69 patients will be complete in February 2018. Conclusion: Preliminary findings indicate that home telemonitoring for HF patients can decrease ED revisits and improve patient experience. The length of stay data may also suggest the potential for early discharge of ED patients with home telemonitoring to avoid or reduce hospitalization. A stepped-wedge randomized controlled trial of TEC4Home in 22 BC communities will be conducted in 2018 to generate evidence and scale up the service in urban, regional and rural communities. This work is submitted on behalf of the TEC4Home Healthcare Innovation Community.
A method for extracting the substrate-independent stress–strain curves of thin films was developed using spherical nanoindentation to investigate the yield behavior of diamond-like carbon (DLC) thin films with Young’s moduli of ∼73 GPa and ∼76 GPa. The resulting stress–strain curves showed that these films commence yielding at ∼13 GPa and ∼14 GPa, respectively. These yield strength values agree with the critical pressure necessary to initiate the transformation of sp2-bonded carbon into significantly harder sp3-bonded carbon, indicating that the yielding of the materials is associated with the sp2-to-sp3 phase transition. The ability of a DLC film to accommodate a progressively increasing contact stress with strain beyond the yield point while dissipating part of the accumulated strain energy, as evidenced in this work, implies a unique mechanism of the brittle material for passively mitigating contact deformation and fracture in tribological applications.
Cronobacter sakazakii is a life-threatening foodborne pathogen found in powdered infant formula and dairy products. Kefir is a dairy probiotic product and its antimicrobial activity against C. sakazakii was reported in our previous study. To identify key microorganisms that mediate growth suppression, we tested the antimicrobial activity of culture supernatants derived from lactic acid bacteria found in kefir. Lactobacillus kefiri DH5, L. kefiranofaciens DH101, and Bifidobacterium longum 720 (a commercial probiotic strain that served as a positive control) all significantly inhibited the growth of C. sakazakii ATCC 29544, delaying the initiation of exponential growth from 3 to 9 h in the nutrient broth. Among them, L. kefiri DH5 exerted the strongest antimicrobial effects against C. sakazakii, showing bactericidal effect at the addition of 300 µl of supernatant in 1 ml of nutrient broth. Interestingly, the supernatant of L. kefiri DH5 has higher pH and lower titrable acidity than that of L. kefiranofaciens DH101, suggesting metabolites produced by heterofermentation of L. kefiri acted more effectively to antagonise the growth of C. sakazakii. In addition, the supernatant of L. kefiri DH5 induced the leakage of cytoplasmic materials including nucleic acid and proteins, suggesting L. kefiri DH5 disrupted the cellular membrane integrity of C. sakazakii. Considering that pH neutralisation reduced the L. kefiri-dependent growth suppression, it is inferred that this activity is mainly due to organic acids produced during the fermentation process.
It has not been well established whether dietary folate intake reduces the risk of diabetes development. We aimed to clarify the prospective association between dietary folate intake and type 2 diabetes (T2D) risk among 7333 Korean adults aged 40 years or older who were included in the Multi-Rural Communities Cohort. Dietary folate intake was estimated from all 106 food items listed on a FFQ, not including folate intake from supplements. Two different measurements of dietary folate intake were used: the baseline consumption and the average consumption from baseline until just before the end of follow-up. The association between folate intake and T2D risk was determined through a modified Poisson regression model with a robust error estimator controlling for potential confounders. For 29 745 person years, 319 cases of diabetes were ascertained. In multivariable analyses, dietary folate intake was inversely associated with risk of T2D for women, not for men. For women, the incidence rate ratio of diabetes in the third tertile compared with the first tertile was 0·57 (95 % CI 0·38–0·87, Pfor trend=0·0085) in the baseline consumption model and 0·64 (95 % CI 0·43–0·95, Pfor trend=0·0244) in the average consumption model. These inverse associations was found in both normal fasting blood glucose group and impaired fasting glucose group among women. Among non-users of multinutrients and vitamin supplements, the significant inverse association remained. Thus, higher dietary intake of folate is prospectively associated with lower risk of diabetes for women.
Image processing and analysis is an effective tool for monitoring and fault diagnosis of activated sludge (AS) wastewater treatment plants. The AS image comprise of flocs (microbial aggregates) and filamentous bacteria. In this paper, nine different approaches are proposed for image segmentation of phase-contrast microscopic (PCM) images of AS samples. The proposed strategies are assessed for their effectiveness from the perspective of microscopic artifacts associated with PCM. The first approach uses an algorithm that is based on the idea that different color space representation of images other than red-green-blue may have better contrast. The second uses an edge detection approach. The third strategy, employs a clustering algorithm for the segmentation and the fourth applies local adaptive thresholding. The fifth technique is based on texture-based segmentation and the sixth uses watershed algorithm. The seventh adopts a split-and-merge approach. The eighth employs Kittler’s thresholding. Finally, the ninth uses a top-hat and bottom-hat filtering-based technique. The approaches are assessed, and analyzed critically with reference to the artifacts of PCM. Gold approximations of ground truth images are prepared to assess the segmentations. Overall, the edge detection-based approach exhibits the best results in terms of accuracy, and the texture-based algorithm in terms of false negative ratio. The respective scenarios are explained for suitability of edge detection and texture-based algorithms.
A single-item depression measure may not be adequate in capturing the complex entity of mental health, despite wide use of this indicator in community studies. This study evaluated the accuracy of a single-question depression measure in comparison to two composite indices–the Center for Epidemiologic Studies Depression Scale (CESD) and the Geriatric Depression Scale (GDS).
Materials and methods:
A total of 800 elderly participants ranging from 60 to 89 years of age and residing in Seoul were recruited using a multistage sampling scheme in 2015. The survey was conducted by trained interviewers with a constructed questionnaire. Reliability and validity measures such as the Kappa index, sensitivity, specificity, PPV, NPV, and AUC were used to evaluate the accuracy of the single question measure. Socio-demographic group differences in accuracy were compared by age, sex, marital status, education, employment, and financial status.
The prevalence of depression by a single-question measure was much lower than those of CESD and GDS (5.5%, 12.3%, and 12.1%, respectively). The sensitivity of the single-item measure, based on CESD and GDS, was extremely low at 30.6% and 36.1%. In the subgroup analysis, however, there was a marked educational discrepancy in all accuracy measures; in sensitivity, people with a university degree or higher showed about 2.4 times higher sensitivity than those having only a primary school education.
The results show that a single-question depression measure should be used with caution. In addition, the single-question measure could substantially underestimate depression among the risk group of older adults.
Ambidexterity organization, which is defined as the ability of an organization to simultaneously pursues exploration and exploitation, has received attention by researchers who have examined its beneficial effect on organizational performance and success. This study attempted to examine the positive effect of ambidextrous organization culture (AOC), which is regarded as the core characteristic of ambidextrous organizations by using a multilevel model. Specifically, this study examined the effects of AOC on members’ job performance and the mediating role of psychological capital in the relationship between AOC and job performance. The results indicated that AOC had a significantly positive relationship with job performance even after controlling various organizational and individual variables. Moreover, we found that psychological capital fully mediated the relationship between AOC and members’ job performance. This study provides theoretical contributions by empirically examining the positive effect and mechanism of AOC. Furthermore, this study offers practical implications in how practitioners can manage their organizational culture, by helping shape the direction of organizational culture management.
We investigate the following nonlinear Neumann boundary-value problem with associated p(x)-Laplace-type operator
where the function φ(x, v) is of type |v|p(x)−2v with continuous function p:
→ (1,∞) and both f : Ω × ℝ → ℝ and g : ∂Ω × ℝ → ℝ satisfy a Carathéodory condition. We first show the existence of infinitely many weak solutions for the Neumann problems using the Fountain theorem with the Cerami condition but without the Ambrosetti and Rabinowitz condition. Next, we give a result on the existence of a sequence of weak solutions for problem (P) converging to 0 in L∞-norm by employing De Giorgi's iteration and the localization method under suitable conditions.
While normative data on neuropsychological performance provide baseline metrics for the assessment and diagnosis of mild cognitive impairment and dementia, a lack of comparative normative data in non-Caucasian populations makes it difficult to conduct similar evaluations and studies in individuals from diverse backgrounds. The current paper aims to provide normative data on a range of cognitive measures in a Korean general population sample and investigate various demographic and health variables associated with cognitive performance in this representative population.
The study population was 1,528 stroke and dementia-free individuals who participated in the Korean Genome and Epidemiology study (KoGES) (mean age 60.43 ± 7.30, 52.42% female). All participants underwent a comprehensive neuropsychological test battery that included verbal and visual memory, language, attention, and executive function measures. A health examination and a questionnaire-based interview were also administered.
The majority of cognitive test results were associated with age, education, and gender. In general, higher education and younger age was associated with better cognitive performance. Explained variance increased modestly in models that included measures of general health and depressive symptoms.
Normative data of cognitive performance in a community based Korean population are presented. These norms provide reference values in a non-Caucasian middle to older aged sample.