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Background: Chronic obstructive pulmonary disease (COPD) is characterized by persistent and progressive airflow obstruction. It is a lung disease with systemic manifestations, which contributes to an increase in morbidity and mortality in the elderly. The greater the severity of the disease, more muscle loss occurs, especially the quadriceps muscle, leading to decreased resistance to exercise, increased fatigue, and dyspnea to small efforts. The presence of COPD is associated with an increased risk of falls, and patients with COPD have a greater imbalance when compared with subjects of the same age without the disease. To investigate whether the different degrees of severity of COPD interfere in the balance, muscle strength, and functional capacity of the patients. Methods: 25 individuals diagnosed with COPD (COPD-G) and 32 individuals without pulmonary disease (CG - Control Group) were assessed. Both groups were submitted to anamnesis, spirometry, dynamometry, manovacuometry, Incremental Shuttle WaIking Test (ISWT), load testing for one repetition maximum (1RM), balance platform assessment, Stair-Climbing Test (SCT) and 6 Minutes Walk Test (6MWT). The variables obtained were compared using the t-test. For comparison between groups, a one-way ANOVA was used. Results: The comparison between the two groups showed a difference in the result of the ISWT, 6MWT and SCT. When compared between groups in different degrees of severity, there was a difference only in SCT between CG and severe COPD-G. There was no significant difference in strength and postural balance. Conclusion: Cardiorespiratory functional capacity is impaired in individuals with COPD and is more evident in the severe stage of the disease. The balance, the strength of the respiratory muscles, upper and lower limbs are similar in the mild, moderate, and severe stages.

High-grade glioma (HGG), including glioblastoma, is the most common primary brain neoplasm and has a dismal prognosis. After initial treatment, follow-up decisions are guided by longitudinal MRI performed at routine intervals. The Brain Tumor Reporting and Data System (BT-RADS) is a proposed structured reporting system for posttreatment brain MRIs. The purpose of this study is to determine the relationship between BT-RADS scores and overall survival in HGG patients.Chart review of grade 4 glioma patients who had an MRI at a single institution from November 2018 to November 2019 was performed. BT-RADS scores, tumor characteristics, and overall survival were recorded. Likelihood of improvement, stability, or worsening on the subsequent study was calculated for each score. Survival analysis was performed using Kaplan-Meier method, log-rank test, and a time-dependent cox model. Significance level of .05 was used.The study identified 91 HGG patients who underwent a total of 538 MRIs. Mean age of patients was 57 years old. Score with the highest likelihood for worsening on the next follow-up was 3b. The risk of death was 53% higher with each incremental increase in BT-RADS scores (hazard ratio, 1.53; 95% confidence interval [CI], 1.07-2.19; p = .019). The risk of death was 167% higher in O-6-methylguanine-DNA-methyltransferase unmethylated tumors (hazard ratio, 2.67; 95% CI, 1.34-5.33; p = .005).BT-RADS scores can be used as a reference guide to anticipate whether patients' subsequent MRI will be improved, stable, or worsened. The scoring system can also be used to predict clinical outcomes and prognosis.

Im et al. [Signature, nullity and determinant of checkerboard colorable virtual links, J. Knot Theory Ramifications 19(8) (2010) 1093–1114] introduced how to define Goeritz matrices for checkerboard colorable virtual links. In this paper, we extend this for the Goeritz matrices of virtual knots. And we consider its signature and determinant and show they are invariants for virtual knots.

Rhythmic auditory cueing (RAC) can improve gait parameters in neurological disorders such as Parkinson's disease and stroke. However, there is a lack of research on the effects of RAC in patients with atypical parkinsonian disorders (APD). Using a smartphone metronome application, we aimed to investigate the immediate effects of RAC in patients with clinically diagnosed APD, namely Progressive Supranuclear Palsy (PSP-Richardson Syndrome and other variants, PSP-nonRS), Corticobasal Syndrome (CBS), Multiple System Atrophy (MSA), and Dementia with Lewy Bodies (DLB). A total of 46 APD participants (25 PSP, 9 CBS, 8 MSA and 4 DLB; age: mean = 70.17, standard deviation = 7.15) walked at their preferred pace for 2 min without any rhythmic auditory cueing (RAC). Participants then walked the same path for another 2 min with RAC set at a tempo 10% faster than the baseline cadence of each participant. After a 10–15-min break, participants walked the same path for another 2 min without RAC to observe for carryover effects. Gait parameters [cadence (steps/minute), gait velocity (meters/minute), and stride length (centimeters)] were collected at baseline, during RAC, and post-RAC. There was a significant improvement in cadence in all participants from baseline to during RAC and post-RAC (corrected p-values = 0.009 for both). Gait velocity also improved from baseline to during RAC and post-RAC in all participants, although this improvement was not significant after correcting for multiple comparisons. The changes in cadence and gait velocity were most pronounced in PSP. In addition, our exploratory analysis showed that the cadence in the suspected TAU group (PSP+CBS) showed a significant improvement from baseline to during RAC and post-RAC (corr. p-value = 0.004 for both). This pilot study using short-term RAC in APD patients demonstrated improvements in cadence and velocity. There is an urgent need for effective gait rehabilitation modalities for patients with APD, and rhythmic cueing can be a practical and useful intervention to improve their gait pattern.

Persons with disabilities (PwD), the world's largest minority, can be more susceptible to particulate matter (PM) than persons without disabilities. Although numerous studies have addressed population susceptibility to PM, PwD have not been studied in air pollution epidemiology. This study investigated the association between short-term exposure to PM with an aerodynamic diameter smaller than 10 μm (PM

Background: Persons with disabilities (PwD), the world’s largest minority, can be more susceptible to particulate matter (PM) than persons without disabilities. Although numerous studies have addressed the population susceptible to PM, PwD have not been studied in air pollution epidemiology. This study investigated the association between short-term exposure to PM with an aerodynamic diameter smaller than 10 μm (PM10) and cardiovascular hospital admissions by the existence of a disability, while also considering individual-level effect modifiers (disability and socio-demographic characteristics) in South Korea.Methods: We used the National Health Insurance Service-National Sample Cohort (NHIS-NSC) to investigate the association between short-term exposure to PM10 and cardiovascular hospital admissions in seven metropolitan cities from 2002 to 2015. We conducted a time-stratified case-crossover analysis using conditional logistic regression and adjusted for daily temperature, relative humidity, air pressure, and national holidays. We conducted stratified analyses according to the existence of a disability, disability type and severity, and socio-demographic characteristics.Results: A 10 μg/m3 increase in the 0-3 moving average level of PM10 was associated with 1.9% (95% confidence interval [CI]: 0.7%, 3.2%) and 0.0% (95% CI: -0.5%, 0.5%) increase in cardiovascular admissions in persons with and without disabilities, respectively. Among PwD, the associations were pronounced in people with brain lesion disorders (percent change [PC]: 2.7%, 95% CI: 0.5%, 5.0%), people with visual impairment (PC: 3.0%, 95% CI: -1.0%, 7.1%), and people with severe disability (PC: 3.0%, 95% CI: 0.9%, 5.0%).Conclusions: We found that PwD may be more adversely affected by PM10 than their non-disabled counterparts. This suggests that PwD is a social identity reflecting the socially marginalized and disadvantaged population in air pollution epidemiology.

We continue the study of the reflexivity of ideals, introduced by Mason, and extend this notion to the subsets in rings. We first construct the smallest reflexive ideal containing [Formula: see text] from any proper ideal [Formula: see text] of any given ring [Formula: see text]; by which we can construct reflexive ideals but not semiprime in a kind of noncommutative ring. A subset [Formula: see text] of a ring [Formula: see text] is called reflexively closed if [Formula: see text] for [Formula: see text] implies [Formula: see text], checking that a ring [Formula: see text] is symmetric if and only if the right (left) annihilator of [Formula: see text] is reflexively closed for any [Formula: see text]. We prove that the set of all nilpotent elements in a ring [Formula: see text] is reflexively closed if and only if [Formula: see text] is nil for any nilpotent element [Formula: see text] in [Formula: see text]; and that the Köthe’s conjecture holds if and only if the union (sum) of the upper nilradical and any nil right ideal is reflexively closed. We provide another process to show that the set of all nilpotent elements of the polynomial ring over an NI ring need not be reflexively closed.

Transition metal dichalcogenides have attracted renewed interest for use as thermoelectric materials owing to their tunable bandgap, moderate Seebeck coefficient, and low thermal conductivity. However, their thermoelectric parameters such as Seebeck coefficient, electrical conductivity, and thermal conductivity are interdependent, which is a drawback. Therefore, it is necessary to find a way to adjust one of these parameters without affecting the other parameters. In this study, we investigated the effect of helium ion irradiation on MoSe2 thin films with the objective of controlling the Seebeck coefficient and electrical conductivity. At the optimal irradiation dose of 1015 cm−2, we observed multiple enhancements of the power factor resulting from an increase in the electrical conductivity, with slight suppression of the Seebeck coefficient. Raman spectroscopy, X-ray diffraction, and transmission electron microscopy analyses revealed that irradiation-induced selenium vacancies played an important role in changing the thermoelectric properties of MoSe2 thin films. These results suggest that helium ion irradiation is a promising method to significantly improve the thermoelectric properties of two-dimensional transition metal dichalcogenides. Graphical Abstract Effect of He+ irradiation on thermoelectric properties of MoSe2 thin films.

We demonstrate a high-performance subwavelength scale plasmonic enhanced graphene/hexagonal boron nitride/graphene-based silicon electro-optic modulator, enabling low energy consumption for applications in communications, nonlinear photonics, and photonic neuromorphic networks.

Studies on the health effects of long-term ozone exposure remain limited with mixed results. One potential source of this inconsistency is the difference in exposure time metrics. This study aimed to investigate the association between long-term exposure to ambient ozone and mortality in South Korea, using different exposure metrics. We also examined whether heterogeneity between previous studies was due to the different exposure metrics. The study population comprised 179,806 participants from the National Health Insurance Service-National Sample Cohort (2002-2015) residing in seven major cities in South Korea. Several ozone exposure metrics (year-round 24-h, year-round 8-h, warm-season 24-h, and warm-season 8-h) were calculated. Time-varying Cox proportional hazards models were used to estimate the association between ozone and all-cause and cause-specific mortalities. Random-effect meta-analysis and meta-regression analysis were performed to pool the effect estimates of previous studies and examine whether the exposure metric can explain the between-study heterogeneity. The hazard ratios (HRs) per 10 ppb increment in year-round 24-h ozone for all-cause (HR, 1.18; 95% CI, 1.07-1.29) and circulatory (HR, 1.52; 95% CI, 1.25-1.84) mortality were higher than those of the other metrics. Year-round 8-h ozone exhibited the largest association with respiratory mortality (HR, 1.43; 95% CI, 1.04-1.96). A meta-analysis of 29 previous studies and the present study showed the largest HR for all-cause mortality from studies using year-round 8-h exposure (HR, 1.014; 95% CI, 0.994-1.033). The exposure metric was significantly associated with effect estimates in the multivariable meta-regression model. In conclusion, in the population-based cohort in South Korea, we found positive associations between several long-term ozone exposure metrics and mortality. The different ozone exposure metrics exhibited heterogeneous effect estimates. A year-round 24-h average ozone metric also could be considered an alternative long-term standard for ozone.

To increase the value of yeast-fermented Korean liquor by-products, we obtained crude polysaccharide (CPS) fractions via ultrasound-assisted extraction and stepwise-gradient ethanol precipitation and investigated their functionality. Nitric oxide production in RAW 264.7 cells was increased following treatment with the CPSs derived from extract. Analysis of the monosaccharide and amino acid composition of the CPS fractions using HPLC revealed that the polysaccharides were mainly composed of glucose (57.2%), mannose (22.6%), and galactose (17.6%), and no amino acids were detected. In addition, a higher concentration of ethanol solvent for fractionation yielded polysaccharides with lower molecular weights (15 kDa). CPS 3 and 4 fractions increased the production of TNF-α (15 and 17-fold, respectively) and IL-6 (20 and 18-fold, respectively) and iNOS (65 and 35-fold, respectively) expression at concentration 12.5 μg/mL compared with levels in non-treated RAW 264.7 cells. Especially, CPS 4 at 200 and 400 μg/mL significantly increased the proliferation of mouse spleen cells by 126% and 153%, respectively. These results indicated that CPS 4 enhanced the proliferation of mouse spleen cells in vivo, indicating its immune-enhancing effects. Therefore, this research can contribute to the development of eco-friendly extraction techniques and immune-enhancing materials.

This study comprehensively presents the relationship between the bioactive substance of 70% (v/v) aqueous ethanol extract of 38 species of seaweeds (SWEs), and anti-glycation activities. The contents of bioactive substance of SWEs, such as total phenolic, total flavonoid and condensed tannins, were determined through a colorimetric analysis. Among the tested species, Ecklonia bicyclis, Ishige foliacea, and Cladophora urightiana var. minor had the highest amount of total phenolic (255.75 mg GAE/g DW), total condensed tannins (63.36 mg CE/g DW), and total flavonoid content (85.26 mg CE/g DW), respectively. Anti-glycation properties of SWEs were evaluated through advanced glycation end-products (AGEs) formation, AGEs-collagen cross-link formation, and AGEs-collagen cross-link breaking assay. Brown algae species exhibited a more prominent inhibitory activity on AGEs formation and AGEs-collagen cross-links, and the breaking of AGEs-collagen cross-links compared to that exhibited by aminoguanidine and ALT-711 (positive controls). Using principal component analysis, we confirmed that the AGEs formation inhibitory property and AGEs-collagen cross-links breaking activity were closely correlated with total phenolic and the condensed tannin contents contained in SWEs. Therefore, the bioactive substances such as phenolics and condensed tannins in seaweeds can be used as predictive indices in selecting compounds for the development of a therapeutic agent that prevents diabetic complications related to the AGEs. In addition, our results suggest that brown algae species, which contains more bioactive substances than green and red algae species, can be utilized as a promising natural resource for the prevention and alleviation of AGEs-related diabetic complications as AGE inhibitor and cross-links breaker.

Despite the remarkable electronic and mechanical properties of graphene, improving the catalytic activity of the atomically flat, inert, and stable carbon network remains a challenging issue in both fundamental and application studies. In particular, the adsorption of most molecules and ions, including hydrogen (H2 or H+), on graphene is not favorable, underlining the challenge for an efficient electrochemical catalytic reaction on graphene. Various defects, edges, and functionalization have been suggested to resolve the catalytic issue in graphene, but cost-effectiveness and active catalysis with graphene have not been achieved yet. Here, we introduce dynamic stacking of reduced graphene oxide (rGO) with spontaneously generated hydrogen bubbles to form an efficient electrochemical catalyst with a graphene derivative; the in operando stacking of rGO, without using a high-temperature-based heteroatom doping process or plasma treatment, creates a large catalytic surface area with optimized edges and acidic groups in the rGO. Thus, the uniquely formed stable carbon network achieves active hydrogen evolution with a Tafel slope of 39 mV·dec-1 and a double layer capacitance of 12.41 mF·cm-2, which breaks the conventional limit of graphene-based catalysis, suggesting a promising strategy for metal-free catalyst engineering and hydrogen production.

We introduce a family of polynomial invariants for flat virtual knots which extend the polynomial introduced by Kauffman and Richter, and we give several properties and examples.

Intestinal epithelial barrier plays an important role to regulate para-cellular transport of water, nutrients and ions and to defend against toxic agents and pathogens as a first barrier. Therefore, maintaining barrier integrity is required to enhance entire gut health. Curcuma longa L. (Turmeric) is a well-known natural product with its outstanding antioxidant and anti-inflammatory properties. However, an aerial part of turmeric such as leaves has been wasted as a byproduct, even though it has a bioactive property. In order to prepare the turmeric leaf polysaccharide fraction (TPF), turmeric leaf water extract was dialyzed with 12~14 kD membrane (MW cut off 12,000) and precipitated with ethanol. A prebiotic activity score of TPF was measured with Lactobacillus plantarum and L.paracasi subsp. tolerans, and compared with that of control, fructooligosaccharides (FOS) and inulin. The score of TPF (1.003 ± 0.197, 0.620 ± 0.143) was higher than that of control (0.168 ± 0.026, 0.187 ± 0.120), and similar to that of FOS (1.138 ± 0.281, 0.938 ± 0.065) and inulin (0.658 ± 0.181, 0.628 ± 0.160). To investigate the effects of TPF on intestinal barrier integrity, the effect of TPF on tight junction was measured in TNF-α induced Caco-2 cells. The result shows that trans-epithelial electrical resistance of TPF treated group was maintained relatively constant until 72 hr at 70.38%, comparingwith that of control group as 28.07%. In addition, TPF significantly increased the expression of tight junction-related proteins such as ZO-1 and Occludin. Taken together, our study demonstrates the prebiotic activity and protective effect of a polysaccharidefraction of turmeric leaf on intestinal epithelial barrier functions.

It is known that only in-plane piezoelectricity exists in pristine two dimensional (2D) transition metal dichalcogenides (TMDs). In this study, we demonstrate the creation of strong out-of-plane piezoelectricity in semiconducting 2H-MoTe2 flakes by an artificial atomic-scale symmetry breaking. The atomic-scale symmetry breaking associated with flexoelectricity was realized through Te vacancy formation by a simple thermal annealing of the 2D TMDs. The strong out-of-plane piezoelectricity was experimentally measured and confirmed by theoretical calculations. This strategy of atomic-scale symmetry modulation for out-of-plane piezoelectricity can be easily applied to a broader class of 2D TMD materials that have not been used for applications with out-of-plane piezoelectricity. Accordingly, it can stimulate the expansion of practical energy device applications with 2D TMD materials.

ObjectivesTo understand a 20-year trend of gender-specific smoking prevalence among adults in South Korea.DesignAge-period-cohort analysis using the intrinsic estimator method was applied to examine the separate contribution of age, period and cohort effect on smoking prevalence. The Driving Force-Pressure-State-Exposure-Effect-Action (DPSEEA) framework was used to explain the observed smoking trends by mapping potential determinants and to address policy implications.SettingGeneral adult population in South Korea.Participants34 828 men and 43 632 women who aged 19–78 years, were not currently pregnant and were without a prior diagnosis of cardiovascular disease or cancer.Outcome measuresGender-specific current smoking prevalence using the 1998–2017 Korea National Health and Nutrition Examination Survey.ResultsOur results showed gender-specific age and birth cohort effects. More specifically, the smoking prevalence peaked at their mid-20s (prevalence rate ratio (PRR): 1.54, 95% CI: 1.49 to 1.59) and cohort born in 1959–1963 (PRR: 1.63, 95% CI: 1.57 to 1.70) and then decreased in men. On the other hand, in women, the smoking prevalence consistently increased until their mid-40s (PRR: 1.53, 95% CI: 1.27 to 1.84) and in recent birth cohort groups (PRR in 1994–1998 cohort: 1.55, 95% CI: 1.13 to 2.13). The period effects declined from 1998−2002 to 2003–2007, following increasing fluctuations in both genders. The smoking-DPSEEA framework showed the absence of policy actions to target female smokers and emphasised a proactive approach that tackles the upstream causes for smoking in women.ConclusionsMen and women are clearly in different phases of the smoking epidemic in Korean population, and gender-tailored policies should be implemented.

The classical Fermi liquid theory and Drude model have provided fundamental ways to understand the resistivity of most metals. The violation of the classical theory, known as non-Fermi liquid (NFL) transport, appears in certain metals, including topological semimetals, but quantitative understanding of the NFL behavior has not yet been established. In particular, the determination of the non-quadratic temperature exponent in the resistivity, a sign of NFL behavior, remains a puzzling issue. Here, a physical model to quantitatively explain the Lifshitz transition and NFL behavior in highly doped (a carrier density of ≈1022 cm-3 ) monoclinic Nb2 Se3 is reported. Hall and magnetoresistance measurements, the two-band Drude model, and first-principles calculations demonstrate an apparent chemical potential shift by temperature in monoclinic Nb2 Se3 , which induces a Lifshitz transition and NFL behavior in the material. Accordingly, the non-quadratic temperature exponent in the resistivity can be quantitatively determined by the chemical potential shift under the framework of Fermi liquid theory. This model provides a new experimental insight for nontrivial transport with NFL behavior or sign inversion of Seebeck coefficients in emerging materials.

Piezoelectricity crystallographically exists only in the in-plane direction in two-dimensional transition metal dichalcogenides. Here, we demonstrated flexoelectricity-tunable out-of-plane piezoelectricity in semiconducting 2H-MoTe2 flakes by creating surface corrugation. In particular, the strong out-of-plane piezoelectricity and its spatial variation depending on local flexoelectricity was observed even though crystallographically there exists only in-plane piezoelectricity. Surface corrugation-mediated flexoelectricity tuning can be applied to other two-dimensional or thin-layered materials and, furthermore, the results could provide useful information on the interweaving nature between mechanical stimulus and electric dipole in low-dimensional materials.

Circularly polarized Raman and/or photoluminescence (PL) analyses have recently been very important in studying physical properties of many layered materials that were either mechanically exfoliated or grown by chemical-vapor-deposition (CVD) on silicon substrates. Since silicon Raman signal is always accompanied by the circularly polarized Raman and/or PL signal from the layered materials, observation of proper circularly polarized Raman selection rules on silicon substrates would be extremely good indicator that the circularly polarized Raman and/or PL measurements on the layered materials were done properly. We have performed circularly polarized Raman measurements on silicon substrates and compared the results with the Raman intensities calculated by using Raman tensors of the diamond crystal structure. Our experimental results were in excellent agreement with the calculation. Similar circularly polarized Raman analysis done on germanium substrate also showed good agreement.

Advanced glycation end-products (AGEs) such as methylglyoxal (MGO) play a vital role in the pathogenesis of nephropathy, a diabetic complication. In the present study, we evaluated the anti-glycation and renal protective properties of Ishige okamurae extract (IOE) against AGE-induced oxidative stress. HPLC analysis confirmed that bioactive phlorotannins such as diphlorethohydroxycarmalol and ishophloroglucin A are predominantly present in IOE. IOE showed strong anti-glycation activities via inhibition of AGE formation, inhibition of AGE–protein cross-linking, and breaking of AGE–protein cross-links. In addition, in vitro studies using mesangial cells demonstrated that IOE effectively suppressed intracellular reactive oxygen species production, intracellular MGO accumulation, and apoptotic cell death by MGO-induced oxidative stress, in addition to regulating the expression of proteins involved in the receptor for AGEs and nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response elements (ARE) signaling pathways. Therefore, IOE can serve as a natural therapeutic agent for the management of AGE-related nephropathy.

Access to urban greenspace has many benefits such as improved health and social cohesion. If access differs by population, these benefits make access to greenspace an environmental justice issue, but little is known regarding accessibility of parks among different sub-groups in Seoul, South Korea. We explored potential socioeconomic inequities for access to parks in Seoul measuring two park provision metrics: total park area per capita (TPPC), and park accessibility index determined by size and proximity of parks. We assessed correlations between a deprivation index for the 25 Gus (administrative unit equivalent to the US borough) and each park provision metric. Regression analyses were applied for the associations between eight socioeconomic indicators of the 424 Dongs (equivalent to the US neighborhood) and each park provision metric. An interquartile range (IQR) increase in percent elderly (⩾65 years) (3.2%) was significantly associated with larger TPPC (1.6 m2/person, 95% CI: 0.8, 2.4). Park accessibility index was associated with more socioeconomic variables than was TPPC. An IQR increase in percent elderly and divorce rates (1.2/1000 population) was associated with increased park accessibility by 3571 km (95% CI: 1103, 6040) and decreased park accessibility by 1387 (95% CI: −2706, −67), respectively. An IQR increase in percentage of the population receiving social low-income support aid (2.2%) was associated with increased park accessibility (reflecting park size and proximity of parks) of residential parks near residential areas by 1568 (95% CI: 15, 3120). Results suggest higher park access for socioeconomically disadvantaged regions. Findings indicate that measures of detailed park access considering spatial proximity and park size may more accurately measure park inequity compared to more basic metrics (e.g. TPPC), which may bias estimation of park inequity by capturing only one characteristic of parks. Detailed park measures should be considered in urban planning and health studies of greenspace.

Doping two-dimensional (2D) semiconductors beyond their degenerate levels provides the opportunity to investigate extreme carrier density-driven superconductivity and phase transition in 2D systems. Chemical functionalization and the ionic gating have achieved the high doping density, but their effective ranges have been limited to ∼1 nm, which restricts the use of highly doped 2D semiconductors. Here, we report on electron diffusion from the 2D electride [Ca2N]+·e– to MoTe2 over a distance of 100 nm from the contact interface, generating an electron doping density higher than 1.6 × 1014 cm–2 and a lattice symmetry change of MoTe2 as a consequence of the extreme doping. The long-range lattice symmetry change, suggesting a length scale surpassing the depletion width of conventional metal–semiconductor junctions, was a consequence of the low work function (2.6 eV) with highly mobile anionic electron layers of [Ca2N]+·e–. The combination of 2D electrides and layered materials yields a novel material design i...

A military vehicle is tested on the standard road surface, which is constructed to be similar to a cross country road surface, in order to evaluate its dynamic performance. The road profile can be changed slowly and continuously by erosion and vehicle movements so that the change might be a large effect on the vehicle performance tests. Therefore, it is necessary to reconstruct and reshape the road surface regularly for the accuracy of the vehicle tests. In this work, the road surface has been obtained by a high-resolution 3D scanner and has been used for extracting road profiles along a direction of travel. Based on the road profile, PSD (Power Spectral Density) has been calculated to evaluate the quality of the road surface. Here, the comparison of two road profiles with different spatial resolutions showed that PSD can be a useful tool indicating the quality of roads. In addition, the generated road surface has been applied to MBD (Multi-Body Dynamics) simulations for obtaining a vehicle’s performance numerically.

The van der Waals (vdW) interaction in two-dimensional (2D)-layered materials affects key characteristics of electronic devices, such as the contact resistance, with a vertical heterostructure geometry. While various functionalizations to manipulate the properties of 2D materials have shown issues such as defect generation or have a limited spatial range for the methods, engineering the vdW interaction in nondestructive ways for device applications has not been tried or properly achieved yet. Here, we introduce the proximity engineering of the vdW interaction in multilayered graphene, which is observed as modified interlayer distances and deviated stacking orders by Raman spectroscopy. A 2D electride, [Ca2N]+·e-, possessing a low-work function of 2.6 eV, was used to trigger an avalanche of electrons over tens of graphene layers, exceeding the conventional spatial-range limit (∼1 nm) by screening with a carrier density of 1014 cm-2. Our proximity engineering reduces the vdW interaction in a nondestructive way and achieves a promising graphene-metal contact resistance of 500 Ω·μm without using complicated edge contacts, which demonstrates a way to use moderately decoupled graphene layers for device applications.

Background The Brain Tumor Reporting and Data System (BT-RADS) is a proposed standardized radiology reporting scheme for MRIs in brain tumor patients. A website was created to introduce the classification system and to promote its use during daily radiology readouts with trainees. Objectives To demonstrate how a website can help implement a structured reporting at a tertiary academic facility. Methods A website, www.btrads.com , including visual aids and an interactive scoring tool was developed to educate trainees about a structured reporting system for brain tumor MRIs. Number of website visitors, resource downloads, and scoring tool users was gathered during the study period of May 1, 2018 to April 30, 2019. Authors surveyed a group of 71 radiology trainees and 34 faculty physicians who care for brain tumor patients to assess the perceived educational and clinical value of BT-RADS. Results The website was visited by 10,058 unique users in one year. The most commonly downloaded support material was the full guide (382 downloads). The interactive scoring tool was used 267 times. The use of BT-RADS at a single institution over 12 months reached over 70%. While survey results from trainees did not reach statistical significance, faculty oncologists, neurosurgeons, and radiologists felt that BTRADS was a valuable clinical tool that improved interdisciplinary communication, facilitated educational discussions, and helped make treatment decisions. Conclusion A website designed to implement a novel structured radiology report facilitated template acceptance across a large neuroradiology section. Groups seeking to modify reporting practices should consider using a website. Funding This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Two-dimensional transition-metal dichalcogenides (TMDs) have a strain-sensitive nature and can only exhibit in-plane piezoelectricity, owing to their in-plane inversion symmetry breaking, which limits their practical applications for vertical stimulations. In this study, we demonstrated the capability of focused ion beams to create out-of-plane piezoelectricity on multi-layered MoTe2. We utilized a focused helium ion beam to selectively pattern the out-of-plane piezoelectricity via defect engineering in a layered MoTe2 flake. The generated out-of-plane piezoelectricity in the desired area was quantitatively examined using atomic force microscopy, and ion beam irradiation-induced defect formation that gave rise to inversion symmetry breaking was confirmed. These results indicated that the out-of-plane piezoelectricity can be selectively patterned through a focused helium ion beam, and it is expected that this approach can also be applied to other classes of TMDs and can expand the application fields of TMD-based devices.

Evidence from cohort studies on the effects of long-term exposure to air pollution on mortality is limited in South Korea, which has high concentration of particles compared to North America, Western Europe, and Japan, and low exposure compared to China. To reduce knowledge gaps between other countries and South Korea, we investigated the association between all-cause, cardiovascular, and respiratory mortality and long-term exposure to PM10 and, as a surrogate for fine particles from local emission sources, SO2 and NO2. Participants comprised 18,220 subjects (97,114.4 person-years) residing in 73 districts of seven major cities of South Korea who were assigned to measurements of fixed-site monitoring stations and followed up. We applied Cox proportional hazard models with time-varying exposure up to three years average of air pollutants. We adjusted for individual and district-level covariates measured at baseline such as age, sex, socioeconomic positions, and health behaviors. We found that hazard ratios of PM10 and SO2 for all-cause mortality leveled off over approximately 5 ppb of SO2 and 35–50 μg/m3 of PM10. Interquartile range increases of PM10 (5.05 μg/m3), SO2 (2.09 ppb), and NO2 (11.41 ppb) were associated with 14.4% (95% CI: −0.4, 31.4), 18.1% (−4.5, 46.0), and 18.9% (−8.7, 54.7) increases in cardiovascular mortality, respectively. We did not find positive associations for respiratory mortality. The increase in cardiovascular mortality varied by sex (for PM10, in females, 27.4% (5.8, 53.5) increase), smoking (in non-smokers, 35.9% (12.7, 64.0) increase), drinking (in drinkers, 24.5% (2.1, 51.8) increase), marital status (in those not married, 23.1% (1.1, 49.9)), employment status (for SO2, in those employed, 79.4% (16.1, 177.3) increase), body mass index (in those ≥23, 47.6% (10.4, 97.3) increase), and community deprivation (for PM10, in less deprived communities, 21.0% (1.3, 44.4) increase). In summary, long-term exposure to air pollution is associated with mortality risk in South Korea. Our results suggest that the health effect of long-term exposure to air pollution may not be equal by sex, health behaviors and socioeconomic positions.

A 44-year-old male initially presented with a right thalamic brain tumor that was confirmed with stereotactic biopsy to be glioblastoma (GBM). The patient was treated with radiotherapy and temozolomide for 6 weeks. At 1 month after completing chemoradiation therapy, the patient underwent follow-up imaging that revealed the primary lesion had mildly responded to chemoradiation, but a secondary lesion had developed along the biopsy needle tract. This secondary lesion was outside of the field of radiation therapy for the primary tumor and concluded to be intracranial spread of GBM along the biopsy tract. The patient’s final imaging 4 months after initial diagnosis revealed the primary and secondary lesions had enlarged. Subsequently, the patient clinically deteriorated and died 7 months after initial diagnosis.

We introduce some polynomial invariants for flat virtual links which are similar to the Jones–Kauffman polynomial, the Miyazawa polynomial and the arrow polynomial for virtual link diagrams, and we give several properties and examples.

We investigate embeddings from the set of long flat virtual knot diagrams to the set of long virtual knot diagrams so that we can construct invariants for long flat virtual knots. Also, we give properties and examples of several invariants for long flat virtual knots via these embeddings and invariants for long virtual knots.