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Background. Yin deficiency (YD) is a pathological condition characterized by emaciation, afternoon fever, dry mouth, and night sweats. The incidence of YD is 23.3%. A 27-item Yin Deficiency Scale (YDS) was developed to estimate the clinical severity of YD. This study aimed to develop three short-form YDS versions to reduce the burden of response time, using three item-reduction approaches: Rasch, equidiscriminatory item-total correlation (EITC), and factor-based analyses. Methods. Two datasets were analyzed from previous studies (169 outpatients from May to June 2009 and 237 healthy college students from January to April 2016). The optimal response category was examined using Rasch analysis. Items with higher item-total correlations were determined using the EITC. Using a factor-based approach, the items were reduced, while maintaining the original YDS construct. Reliability was estimated using the person separation index (PSI) and Cronbach's α values. The predictive accuracy was examined using the area under the curve (AUC). Finally, the relationship between YD and dysfunctional breathing (DB) was examined using factor scores from the YDS and the Korean version of the Nijmegen Questionnaire (KNQ). Results. We developed two 14-item YDS versions using the Rasch and EITC approaches, and a 16-item YDS version using a factor-based approach. Rasch analysis suggested an optimal response category of five points. The PSI of Rasch and Cronbach's α of the EITC and factor-based versions were 2.19, 0.855, and 0.827. The AUCs of the three short-form YDS were 0.812, 0.811, and 0.818. The sensitivity of the EITC-YDS was 0.632, which was lower than its specificity of 0.875. The fatigue-related scores of the factor-based YDS were fairly correlated with the factor scores of the KNQ estimating the DB (r = 0.349–0.499). Conclusion. The 14-item Rasch- and 16-item factor-based YDS may replace the original YDS during YD's primary screening, epidemiological surveys, and health checkups. [ABSTRACT FROM AUTHOR]

The 25-item Phlegm Pattern Questionnaire (PPQ) has been widely used to examine the relationship between the phlegm pattern (PP), quality of life, tongue colour, vocal qualities, and dysfunctional breathing. However, the concerns of response burden and differences in the respondent's abilities or item difficulty for the original version of the PPQ have not been sufficiently addressed. This study aimed to develop a short-form PPQ using Rasch analysis, an item response theory. Based on the retrospective data, the response order, differential item functioning (DIF), dimensionality, reliability, concurrent validity, and fitting errors were examined for 291 normal participants and 61 inpatients. The discriminative ability of the short-form PPQ was examined using receiver operating characteristic curve analysis. Along with Rasch analysis, another short-form PPQ was developed using equidiscriminative item-total correlation (EITC) analysis and the results between the two short-form PPQs were compared accordingly. Rasch analysis results suggested a 6-point response category for the PPQ, and finally, 8 items without fitting errors or DIF variability were selected for the PPQ (PPQ-8). The PPQ-8 had satisfactory reliability (person separation index = 2.23), unidimensionality (unexplained variance in the first contrast = 1.598), fitting levels (infit mean square, 0.80–1.39; outfit mean square, 0.79–1.34), sensitivity (70.5%), and specificity (76.5%). The PPQ-8 had a moderate discriminative ability of the PP (area under the curve = 0.759), and the cut-off point was 23. Although the 8-item PPQ developed using EITC analysis showed similar levels of reliability, validity, and discriminative ability of the PP to the PPQ-8, it could not present the information of item hierarchy and differences in the respondents' abilities. In conclusion, the PPQ-8 by Rasch analysis is recommended for future use to evaluate the clinical severity of PP. [ABSTRACT FROM AUTHOR]

Background: Sjogren's syndrome (SS) is a heterogenous disease with various phenotypes. We aimed to provide a relevant subclassification based on symptom-based clustering for patients with primary (p) SS.Methods: Data from patients in a prospective pSS cohort in Korea were analysed. Latent class analysis (LCA) was performed using patient reported outcomes, including pain, fatigue, dryness, and anxiety/depression. Clinical and laboratory differences between the classes were analysed. Latent transition analysis (LTA) was applied to the longitudinal data (annually for up to 5 years) to assess temporal stability of the classifications.Results: LCA identified three classes among 341 patients with pSS (i.e., 'high symptom burden', 'dryness dominant', 'low symptom burden'). Each group had distinct laboratory and clinical phenotypes. LTA revealed that class membership remained stable over time. Baseline class predicted future salivary gland function and damage accrual represented by a Sjogren's syndrome disease damage index.Conclusion: Symptom-based clustering of heterogenous patients with primary Sjogren's syndrome provided a relevant classification supported by temporal stability over time and distinct phenotypes between the classes. This clustering strategy may provide more homogenous groups of pSS patients for novel treatment development and predict future phenotypic evolvement. [ABSTRACT FROM AUTHOR]

Background: Deep spinal infection is a devastating complication after epidural injection. This study aimed to investigate the incidence of deep spinal infection primarily after outpatient single-shot epidural injection for pain. Secondarily, this study assessed the national trends of the procedure and risk factors for said infection.Methods: Using South Korea's National Health Insurance Service sample cohort database, the 10-yr national trend of single-shot epidural injections for pain and the incidence rate of deep spinal infection after the procedure with its risk factors were determined. New-onset deep spinal infections were defined as those occurring within 90 days of the most recent outpatient single-shot epidural injection for pain, needing hospitalization for at least 1 night, and receiving at least a 4-week course of antibiotics.Results: The number of outpatient single-shot epidural injections per 1,000 persons in pain practice doubled from 40.8 in 2006 to 84.4 in 2015 in South Korea. Among the 501,509 injections performed between 2007 and 2015, 52 cases of deep spinal infections were detected within 90 days postprocedurally (0.01% per injection). In multivariable analysis, age of 65 yr or more (odds ratio, 2.91; 95% CI, 1.62 to 5.5; P = 0.001), living in a rural area (odds ratio, 2.85; 95% CI, 1.57 to 5.0; P < 0.001), complicated diabetes (odds ratio, 3.18; 95% CI, 1.30 to 6.7; P = 0.005), multiple epidural injections (three times or more) within the previous 90 days (odds ratio, 2.34; 95% CI, 1.22 to 4.2; P = 0.007), and recent use of immunosuppressants (odds ratio, 2.90; 95% CI, 1.00 to 6.7; P = 0.025) were significant risk factors of the infection postprocedurally.Conclusions: The incidence of deep spinal infection after outpatient single-shot epidural injections for pain is very rare within 90 days of the procedure (0.01%). The data identify high-risk patients and procedure characteristics that may inform healthcare provider decision-making.Editor’s Perspective: [ABSTRACT FROM AUTHOR]

Dysfunctional breathing (DB) is characterized by abnormal breathing patterns and often results from psychogenic causes in the absence of organic diseases. Although acupuncture and herbal treatments have been suggested as alternative therapies for DB, few studies have addressed the relationship between DB and pathological patterns from a diagnostic perspective. We asked 237 college students (130 men aged 21.4 ± 1.9 years; 107 women aged 21.4 ± 3.0 years) to complete the Korean version of the General Health Questionnaire-30 (K-GHQ-30) and four validated pathological pattern questionnaires regarding qi and yin deficiencies, phlegm, and cold-heat patterns. The Korean version of the Nijmegen Questionnaire was used to classify participants into DB and non-DB groups. Effects of age, gender, and DB on pathological patterns were examined using simple regression and two-way MANCOVA models. Age had an effect on all pattern scores except heat pattern scores (β: 0.154–0.098). DB group showed a moderate main effect (η2 = 0.167) on pathological patterns, while gender showed a minimal main effect (η2 = 0.096); qi and yin deficiencies, phlegm, and cold-heat pattern scores in DB and female groups were higher than those in non-DB and male groups. The K-GHQ-30 scores showed significant positive correlations with the pathological pattern scores (r: 0.243–0.533), indicating that disruption of pathological patterns could be associated with patients' psychological disturbance. In conclusion, these questionnaires may help to identify pathological patterns related to DB and determine individually tailored alternative therapies. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the effect of acupuncture intervention and manipulation types on poststroke dysarthria. Electronic database, including PubMed, CENTRAL, Scopus, RISS, and CNKI, were searched for randomized controlled trials (RCT), treating dysarthria using acupuncture, speech-language therapy (SLT), and general management (GM), published before April 2019. The number, distribution, intensity, depth, and repetition of acupuncture and bleeding therapy on the sublingual veins were considered as manipulation types. Risk of bias of the included trials was evaluated, and their efficacy was assessed using risk ratio (RR) and the standard mean differences in the Frenchay Dysarthria Assessment and Speech Function Grading, with 95% confidence intervals (CIs).Fifteen RCT trials involving 1453 patients were isolated. Electroacupuncture plus SLT and manual acupuncture plus SLT were more effective than SLT only, respectively (RR = 1.520, 95% CI [1.183–1.952], RR = 1.380, 95% CI [1.281–1.488]). The clinical efficacy of acupuncture plus GM was higher than that of GM alone (RR = 1.165, 95% CI [1.050–1.293]). Meta-ANOVA showed that none of the manipulation types increased the clinical efficacy of acupuncture on dysarthria. The methodological quality was low. In conclusion, our study suggests that the effect of acupuncture on poststroke dysarthria may be maximized when manual acupuncture or electroacupuncture is combined with SLT, irrespective of manipulation types. [ABSTRACT FROM AUTHOR]

Wurtzite BAlN alloy with large bandgap is an emerging material system for UV optoelectronic and power devices. In this study, the BAlN/GaN heterojunction with a sharp interface and uniform distribution of the elements was formed by careful control of epitaxial conditions to avoid GaN desorption and parasitic reactions whose band alignment was then measured for the first time. The valence band offset (VBO) was found to be nearly-zero, i.e. −0.2 ± 0.2 eV, in the B 0.14 Al 0.86 N/GaN heterojunction by X-ray photoelectron spectroscopy. Additionally, the conduction band offset (CBO) is estimated at 2.1 ± 0.2 eV, which is the largest reported CBO among epitaxial GaN-based heterojunctions. In comparison to the type-I Al 0.75 Ga 0.25 N/GaN heterojunction (both Al 0.75 Ga 0.25 N and B 0.14 Al 0.86 N alloy have the same bandgap of 5.7 eV), the CBO and VBO of the B 0.14 Al 0.86 N/GaN heterostructure are significantly larger and smaller, respectively. The nearly-zero VBO and the very large CBO of the B 0.14 Al 0.86 N/GaN heterojunction could potentially lead to considerable performance enhancement for GaN optoelectronics and power electronics devices. [ABSTRACT FROM AUTHOR]

The effect of ZnO nanostructures on the light output power of 375 nm near-ultraviolet light-emitting diodes (NUV-LEDs) was investigated by comparing one-dimensional (1D) nanorods (NR-ZnO) with two-dimensional (2D) nanosheets (NS-ZnO). ZnO nanostructures were grown on a planar indium tin oxide (ITO) by solution based method at low temperature of 90°C without degradation of the forward voltage. At an injection current of 100 mA, the light output efficiency of NUV-LED with NR-ZnO was enhanced by around 30% compared to the conventional NUV-LEDs without ZnO nanostructures. This improvement is due to the formation of a surface texturing, resulting in a larger escape cone and a multiple scattering for the photons in the NUV-LED, whereas the light output efficiency of NUV-LED with NS-ZnO was lower than that of the conventional NUV-LEDs due to the internal reflection and light absorption in the defective sites of NS-ZnO. [ABSTRACT FROM AUTHOR]

Abstract: A dramatic reduction in threading dislocation density and stress-relaxation was simultaneously achieved in GaN epilayer using a silica nanosphere embedded structure on V-groove patterned sapphire substrate by metal-organic chemical vapor deposition. By depositing silica nanospheres at two different instances during a growth process, a two-step growth that included selective area growth and lateral overgrowth was initiated. This approach led to GaN template of high crystal quality, which was confirmed from x-ray diffraction rocking curve and micro-Raman measurements and further corroborated by transmission electron microscopy. GaN light-emitting diode fabricated by this strategy showed a significant enhancement in the light output power. [Copyright &y& Elsevier]

Abstract: Selective growth by metal-organic chemical vapor deposition (MOCVD), and electrochemical etching of a heavily Si-doped GaN (n+-GaN) interlayer were employed to obtain air-gaps embedded in a u-GaN layer. As confirmed by Raman spectroscopy, the introduction of an n+-GaN, which was later etched to obtain air-gaps, also enhanced the strain-compliance of GaN epilayer on sapphire substrate. An enhanced electroluminescence emission was observed from the light-emitting diodes (LEDs) fabricated on the air-gap embedding template. Using theoretical LED simulation, it was discerned that the increase in optical emission from the LED was caused predominantly by the redirection of photons at GaN/air-gap interface. Finite-difference time domain (FDTD) simulation method was employed to understand the mechanism of optical emission enhancement and its spatial variation over the LED surface. [Copyright &y& Elsevier]

Abstract: A two-step growth approach based on facet-controlled epitaxial lateral growth and the application of silica nanospheres was established to enhance the performance of GaN based light-emitting diodes (LEDs). In the first step, open inverted honeycomb cones (IHCs) were fabricated. These IHCs were filled with silica nanospheres and a second growth step was performed. As compared to LEDs fabricated on IHC templates, 2.7 fold electroluminescence (EL) intensity was obtained for silica nanospheres-stacked IHC due to improved crystal quality and light scattering at silica nanospheres. Simulation of emission intensity was carried out to determine the effect of dislocation density reduction on EL enhancement of the LEDs. [Copyright &y& Elsevier]

Objectives: Season of birth (SOB) is a medical term used to describe the relationship between the season in which one is born and his or her physiologic and pathological characteristics. In East Asian medicine, the Un-Gi SOB is based on the Yin-yang-Five Phases theory. The purpose of this study is to examine the relationship between Un-Gi SOB and a multitude of clinical symptoms and signs, and to examine which of the Un and Gi seasons has the greatest impact on these symptoms and signs. Methods: Using the Delphi method, three Un- Gi experts formulated a 26-item questionnaire consisting of clinical symptoms and signs, with each item rated on a Likert 7-point scale. A total of 1057 Korean adolescents (583 males, 474 females) completed the 26-item questionnaire. After identifying the Un and Gi seasons of all subjects, item scores were evaluated to determine whether there was a difference between Un and Gi seasons. Results: For Un seasons, males born in the Wood season had greater indigestion and were less physically active, whereas females born in the Earth season were better able to concentrate but had slower rates of growth. For Gi seasons, males born in the Fire season had greater indigestion and morning fatigue, and males born in the Earth season had higher tension. There was no relationship between symptoms, signs, and the Gi SOB in females. This indicates that males born in Wood Un and Gi seasons are susceptible to Earth-related clinical problems, whereas females born in the Earth Un season are susceptible to Earth-related clinical problems. Conclusions: The study results suggest that Un- Gi seasons based on the Yin-yang-Five Phases are related to clinical symptoms and signs, with significant differences between genders. [ABSTRACT FROM AUTHOR]

Objectives: Yin Deficiency (YD) is a pathophysiologic pattern that manifests with emaciation, dry mouth, tidal fever, Five Center Heat, night sweats, and malar flushing. The purpose of the present study was to develop and validate a new YD metric, the Yin Deficiency Scale (YDS), to define an optimum cutoff point for the YDS, and to examine the relationships between YD and Cold-Heat patterns. Methods: A total of 169 outpatients and 83 college students were asked to complete the YDS. The college students were also asked to complete the Yin Deficiency Questionnaire (YDQ) and Cold-Heat Questionnaire (CHQ). Twelve clinicians determined whether or not the 169 outpatients had YD. YDS and YDQ data were used to estimate the internal consistency, construct validity, and concurrent validity of the YDS. CHQ data were used to examine the relationships between YDS and CHQ subscale scores. Total YDS scores and the clinicians' diagnoses of the outpatients were used to define an optimum cutoff score for the YDS. Results: The 27-item YDS had satisfactory internal consistency (α=0.885) and concurrent validity, with correlations between the YDS and YDQ subscale scores. A total of eight factors were extracted in the test of construct validity, using principal component analysis, and the overall variance explained by all factors was 63.1%. Among the eight factors, cough, fever, and skin-related factors were associated only with Heat pattern, whereas pain, urine, and fatigue-related factors were associated with both Cold and Heat patterns. In the receiver operating characteristic curve analysis, the sensitivity, specificity, and area under the curve of the YDS were 73.7%, 84.8%, and 0.875, respectively. The optimum cutoff score was defined as 10 points. Conclusions: The results of this study suggest that the YDS is a reliable and valid instrument for evaluating YD. [ABSTRACT FROM AUTHOR]

Objectives: The present study was conducted to examine the reliability and validity of a Phlegm Pattern Questionnaire (PPQ) that was developed within the context of Traditional Chinese Medicine. Methods: A total of 292 normal subjects and 61 inpatients were asked to complete the PPQ. Among the 292 normal subjects, 73 college students were additionally asked to complete the Profile of Mood States (POMS) and the Chalder Fatigue Scale (CFS). Three (3) clinicians determined whether the 61 inpatients exhibited the Phlegm Pattern (PP). The authors estimated the internal consistency and construct validity for the PPQ using data from the normal and inpatient subjects. The POMS and CFS data were used to evaluate the concurrent validity of the PPQ. PPQ data and the clinicians' diagnoses of the inpatient subjects were used to estimate the sensitivity and specificity and to define the optimum cut-off point of the PPQ. Results: The PPQ had satisfactory internal consistency (α=0.902 in normal subjects, α=0.919 in inpatient subjects) and concurrent validity, with significant correlations between the total score of the PPQ and all of the POMS and CFS subscales. In a test of construct validity using principal component analysis, a total of six factors were extracted, and the overall variance explained by all factors was 58.9%. In the test of discriminant validity using receiver operating characteristic curve analysis, the sensitivity, specificity, and area under the curve were 83.78%, 83.33%, and 0.860, respectively. The optimum cut-off level was defined as five points. Conclusions: These results suggest that the PPQ is a reliable and valid self-rating instrument for estimating the severity of PP. [ABSTRACT FROM AUTHOR]

By use of HPLC-UV-APCI-MS, the chemical nature of chlorophyll degradation products (CpD) in the excreta of the silkworm (Bombyx mori) was clarified in relation to its photosensitizing efficacy in photodynamic therapy (PDT) of tumors in vitro. Besides CpD from silkworm excreta aged in nature for more than a year, mulberry leaves, substances in the digestive system of silkworms fed on the mulberry leaves, and fresh excreta less than 24 hrs old were analyzed and compared. The CpDs isolated were separated and characterized, and their photosensitizing efficacy in experimental PDT was evaluated. Among the agents characterized by HPLC-UV-APCI-MS, pheophorbide-a and pyropheophorbide-a exerted the most potent photosensitizing effect in vitro. Although these pigments were detected in silkworm excreta, the amounts extracted were significantly higher in materials aged for more than one year. Yields from fresh excreta or digestive tract contents were lower than from stored excreta. None of those CpDs were detected in mulberry leaves. Natural environments presumably provide favorable conditions for the degradation of chlorophyll to pheophorbide-a and/or pyropheophobide-a. [ABSTRACT FROM AUTHOR]

We demonstrate the use of CdSe quantum dots (QDs) as an interlayer for improving photovoltaic performance in the inverted polymer solar cells (iPSCs). The conjugation of CdSe and CdSe@ZnS core@shell QDs between polyethylenimine ethoxylated (PEIE) polymer and PTB7:PC71BM blended layer played an important role in increasing the short circuit current density by Förster resonance energy transfer (FRET) and efficient charge transport. The drastic mutual photoluminescence quenching suggests that the photon energy absorbed by PTB7:PC 71 BM are effectively transferred to the QDs. The PTB7:PC 71 BM based iPSCs with the CdSe QDs interlayer exhibits higher power conversion efficiency of 8.13%, which is 13.4% higher than that of the control device. The iPSCs with CdSe@ZnS QDs interlayer showed relatively lower PCE of 7.31%, which could be due to an increase in carrier recombination inside QDs by relatively high energy level of ZnS shell. As a consequence, the enhanced photovoltaic performance of iPSCs with CdSe QDs interlayer can be attributed to an effective charge transport and an increase in the overall photocurrent by FRET. Image 101467 • CdSe QDs monolayer acts as an effective interlayer for improving photovoltaic performance of iPSCs. • The CdSe QD interlayer improves photovoltaic performance of the iPSCs more than CdSe@ZnS QDs. • The CdSe QDs play essential roles in increasing the overall photocurrent by FRET and efficient charge transport. [ABSTRACT FROM AUTHOR]

The aggregation of zinc oxide nanoparticles leads to an increased absorbance in the ultraviolet-visible region by an induced light scattering effect. Herein, we demonstrate the inhibition of photoconversion activity in ZnO-graphene core-shell quantum dots (QD) (ZGQDs) agglomerated by 4-aminophenol (4-AP) used as a linker. The ZnO-graphene quantum dots (QD) aggregates (ZGAs) were synthesized using a facile solvothermal process. The ZGAs revealed an increased absorbance in the wavelengths between 350 and 750 nm as compared with the ZGQDs. Against expectation, the calculated average photoluminescence lifetime of ZGAs was 7.37 ns, which was 4.65 ns longer than that of ZGQDs and was mainly due to the high contribution of a slow (τ2, τ3) component by trapped carriers in the functional groups of graphene shells and 4-AP. The photoelectrochemical (PEC) cells and photodetectors (PDs) were fabricated to investigate the influence of ZGAs on the photoconversion activity. The photocurrent density of PEC cells with ZGAs was obtained as 0.04 mA/cm2 at 0.6 V, which was approximately 3.25 times lower than that of the ZGQDs. The rate constant value of the photodegradation value of rhodamine B was also decreased by around 1.4 times. Furthermore, the photoresponsivity of the PDs with ZGAs (1.54 μA·mW−1) was about 2.5 times as low as that of the PDs with ZGQDs (3.85 μA·mW−1). Consequently, it suggests that the device performances could be degraded by the inhibition phenomenon of the photoconversion activity in the ZGAs due to an increase of trap sites. [ABSTRACT FROM AUTHOR]

• The hybrid graphene quantum dots (GQDs)/ZnO nanoflowers (NFs) were fabricated. • The large surface area of ZnO NFs leads to more efficient integration of GQDs. • The hybrid GQD/ZnO NFs structure showed strong photoluminescence emission. • The radiative recombination can be enhanced by energy transfer phenomena. We report the fabrication of hybridization between graphene quantum dots (GQDs) and ZnO nanoflowers (NFs) for mediating photoluminescence by using a straightforward solution-based technique. Hydrothermally grown two-dimensional ZnO NFs played an essential role in assembling GQDs. The large surface area to volume ratio of ZnO NFs led to a highly dense distribution of GQDs, giving rise to photoluminescence (PL) emission at around 442 nm from GQDs and the synergic effects. Thus, GQDs/ZnO hybrid results in strong and broad PL over the spectral range from near UV to red region. We also suggested that an energy interaction between GQDs and various defect sites in ZnO NFs can promote the radiative recombination of both components, thereby providing PL peak intensities more than two times higher than individual components. Fabricated GQDs/ZnO heterojunctions on both soft and hard substrates emit similar intense and wide PL spectrum under ultraviolet irradiation, indicating that this heterojunction can consider as a promising platform for flexible and transparent optoelectronic applications. [ABSTRACT FROM AUTHOR]

We demonstrate the ZnO@graphene core@shell quantum dot (ZGQDs) fabricated by selectively engineering of oxygenated functional groups on the graphene shells with eco-friendly keratin textile for transparent and flexible UV photodetector devices. The ZGQDs with the octylamine (ZGQDs-OA) and the graphene sheet were employed as an active material and an electron transport channel. The functional groups on the surrounding graphene shell in ZGQDs were passivated by the OA, resulting in a good absorbance in UV light and excellent carrier transport properties. The passivation of the functional groups on the graphene shell by OA drastically enhanced the photocurrent. Optical transmittance of the ZGQDs-OA/graphene sheets/PMMA/keratin nanofiber textile composites structures was approximately 77% at the visible spectrum range. Current–voltage (I-V) and current–time (I-t) measurements on the UV photodetector under illumination state in bending condition exhibited the excellent ON/OFF switching states and stability. The photosensitivity and responsivity of the photodetector with ZGQDs-OA were found to be around 13.10 and 68.64 μAmW−1, respectively, which is much higher than that without the passivation. The improved performance of the photodetector with ZGQDs-OA could be attributed to the efficient electron transport to the electrode by the passivation of the graphene on ZnO QDs. Image 1 • The surface modified ZGQDs have excellent UV absorption and carrier transport properties. • The passivation of the functional groups on the graphene shell was effectively prevents the electron trap. • The ZGQDs-Octylamine on eco-friendly textile structures for flexible UV photodetectors were successfully fabricated. [ABSTRACT FROM AUTHOR]

Symptomatic hyperventilation (SH) is a pathological condition that manifests with breathlessness, dyspnea, light-headedness, anxiety, and paresthesia. However, little is known about the prevalence of SH and its association with health-related quality of life (HRQoL) in a young population. The Nijmegen questionnaire (NQ), which measures severity of SH, had not previously been cross-culturally translated into Korean. In this study, the NQ was cross-culturally translated into Korean (KNQ), using translation and back-translation methods. To examine the reliability and validity levels of the KNQ, as well as its association with HRQoL, 237 college students (21.38 ± 2.45 years) were asked to complete the KNQ, the Korean version of the general health questionnaire (K-GHQ-30) and the short form-36 (K-SF-36). The KNQ showed satisfactory reliability (Cronbach’s α = 0.878). In the construct validity test, four factors (neuropsychological, respiratory, neurogastrointestinal, and neuromuscular) were extracted (% of total variance = 59.8). Using a KNQ cut-off score of 23 points, the prevalence of SH was 22.8%. Physical and mental HRQoL levels estimated by the K-GHQ-30 score and the 8 subscale scores of the K-SF-36 were lower in the SH group than in those of the non-SH group. It is concluded that the cross-culturally translated KNQ is reliable and valid, and management of SH may prevent a reduction in physical and mental HRQoL in a young population. [ABSTRACT FROM AUTHOR]

This paper provides two types of engineering J estimation equations for cylinders with finite internal axial surface cracks under internal pressure. The first type is the so-called GE/EPRI type J estimation equation based on Ramberg–Osgood (R–O) materials. Based on detailed 3-D FE results using deformation plasticity, plastic influence functions for fully plastic J components are tabulated for practical ranges of the mean radius-to-thickness ratio, the crack depth-to-length ratio, the crack depth-to-thickness ratio, the strain hardening index for the R–O material, and the location along the semi-elliptical crack front. Based on tabulated plastic influence functions, the GE/EPRI-type J estimation equation along the crack front is proposed and validated for R–O materials. For more general application, for instance, to general stress–strain laws, the developed GE/EPRI-type solutions are then re-formulated based on the reference stress concept. Such a re-formulation provides a simpler equation for J, which is then further extended to combined internal pressure and bending. The proposed reference stress based J estimation equation is compared with elastic–plastic 3-D FE results using actual stress–strain data for a Type 304 stainless steel. Good agreement between the FE results and the proposed reference stress based J estimation provides confidence in the use of the proposed method for elastic–plastic fracture mechanics of pressurised piping. [Copyright &y& Elsevier]

This paper proposes engineering estimation equations of elastic–plastic J and crack opening displacement (COD) for axial through-wall cracked pipes under internal pressure. On the basis of detailed 3D finite element (FE) results using deformation plasticity, the plastic influence functions for fully plastic J and COD solutions are tabulated as a function of the mean radius-to-thickness ratio, the normalised crack length, and the strain hardening. On the basis of these results, the GE/EPRI-type J and COD estimation equations are proposed and validated against 3D FE results based on deformation plasticity. For more general application to general stress–strain laws or to complex loading, the developed GE/EPRI-type solutions are re-formulated based on the reference stress (RS) concept. Such a re-formulation provides simpler equations for J and COD, which are then further extended to combined internal pressure and bending. The proposed RS based J and COD estimation equations are compared with elastic–plastic 3D FE results using actual stress–strain data for Type 316 stainless steels. The FE results for both internal pressure cases and combined internal pressure and bending cases compare very well with the proposed J and COD estimates. [Copyright &y& Elsevier]

An attempt to degrade volatile organic compounds (VOCs) and sterilize air simultaneously is highly desirable to improve indoor air quality. With the help of deep ultraviolet (UVC) lighting, harmful bacteria that exists in the air can be destroyed. Thus, a new photocatalytic substance that can break down VOCs under UVC irradiation is required. Here, we demonstrate the photocatalytic activity of β-Ga2O3 nanostructures, synthesized via the solvothermal method for removing formaldehyde (HCHO) under deep ultraviolet irradiation. The Raman and XRD results indicated that as-synthesized nanostructures showed β-crystalline phase with a monoclinic structure. The photoluminescence spectrum exhibited a broad and strong green emission peak at 510 nm, which was likely attributed to a considerable amount of oxygen and gallium vacancies formed during the calcinating process. The photocatalytic efficiency for decomposing HCHO at room temperature under deep ultraviolet irradiation (278 nm) of the synthesized β-Ga2O3 nanoparticles is higher than that of the β-Ga2O3 nanorods. Both nanoparticles and nanorods obeyed the pseudo-first-order Langmuir-Hinshelwood kinetic model with a degradation rate constant of 0.057 and 0.033 min−1, corresponding to the efficiency of 82% and 62% in the formaldehyde removal, respectively. [ABSTRACT FROM AUTHOR]

Although both III-N laser diodes (LDs) and LEDs employ electron blocking layers (EBLs) to reduce electron leakage from the active region, LDs typically operate at far higher current densities than LEDs. Shortcomings of the common rectangular EBL are discussed. Two alternative EBL designs have been systematically studied using numerical simulation: the inverse-tapered EBL and the inverse-tapered step-graded EBL. It is shown that the efficacy of each of these EBL designs depends strongly on the operational current density, suggesting that the EBL design considerations for III-N LDs and LEDs are fundamentally different. [ABSTRACT FROM AUTHOR]

Lateral hole injection into AlGaN-based ultraviolet (UV) vertical-cavity light-emitting lasers (VCSELs) has been studied via numerical simulation. For blue and violet vertical cavity light emitters, indium tin oxide (ITO) is most commonly used as a transparent current spreading layer to increase the overlap between the optical mode and the radial current profile. However, ITO has very high optical losses in the UV spectrum, so alternative schemes for lateral current spreading have been investigated for use in UV-VCSELs. A modulation doped short-period superlattice (MD-SPSL) has been proposed as a transparent lateral current spreading layer in UV-VCSELs. The narrow bandgap unintentionally doped (uid) material maintains a high mobility due to reduced impurity scattering and has a high free hole concentration due to modulation doping, thus forming highly conductive channels which aid lateral hole transport. This has been shown to partially mitigate current crowding around the current aperture. To account for imperfect modulation doping due to the magnesium memory effects and other factors, the effect of varying the hole mobility in the uid-narrow bandgap layer of the MD-SPSL from 13–300 cm2/($\text {V}\cdot \text {s}$) on the threshold current and slope efficiency has also been studied. Employing an MD-SPSL results in a significant reduction in the threshold current and slope efficiency compared to ITO, and the extent of the improvement depends on the hole mobility in the uid-AlGaN layer. [ABSTRACT FROM AUTHOR]

Tongue diagnosis is a technique used to determine cold-heat pathologic patterns (CHPPs). Herein, we reviewed electronic medical records of tongue temperature measured using infrared thermography (IRT), tongue color (luminance, green/red, and blue/yellow balance), cold-heat pattern questionnaires (CHPQ), and body temperature for 134 women with gynecological problems (age, 38.97 ± 11.49 years). The temperatures of seven tongue regions (root, center, tip, and both sides of the center and root) were determined, and the effects of age, regional differences, and their correlations with color parameters were examined. Factor analysis was conducted separately with the 10 cold pattern (CP) and 10 heat pattern (HP) items. Tongue temperature showed an age effect (β; -0.198 to -0.210) and regional differences (both sides of the root > center and root > tip). Tongue temperature was positively correlated with luminance (r: 0.236-0.246), indicating that a higher temperature was associated with a brighter color. The factor analysis extracted two factors (cold sensitivity-pain and discharge-complexion factors) from the CP items and three factors (heat sensation-pain, discharge-breath, and cold preference-thirst factors) from the HP items. Tongue temperature was negatively correlated with the discharge-complexion factor of CP and the discharge-breath factor of HP (r: -0.171 to -0.203), indicating that a lower tongue temperature may be a consequence of emission of excessive heat in HP and a lower blood perfusion in CP. Body temperature did not correlate with the CHPQ factor scores. In conclusion, tongue temperatures measured using IRT may be a partial indicator of CHPPs. [ABSTRACT FROM AUTHOR]

We investigated the thermal stability and electrical properties of nitrogen-doped reduced graphene oxide (NrGO)/ n –type Si solar cells. A NrGO layer was used as a transparent electrode as well as an electron-hole separation layer simultaneously. The effect of doping on the carbon and nitrogen bonding configurations in NrGO was investigated using X–ray photoelectron spectroscopy (XPS). The XPS data indicate that pyridinic–N is the dominant bonding configuration. This bonding configuration leads to a reduction in the power conversion efficiency and a decrease in the short circuit current. However, on being subjected to thermal oxidation, the NrGO/ n –type Si solar cells exhibit a smaller variation in series resistance compared to the undoped rGO/Si solar cells. Results of accelerated thermal tests suggest that nitrogen doping prevents re-oxidation of the reduced graphene oxide layer. [ABSTRACT FROM AUTHOR]

We investigated the effect of the size of graphene oxide (GO) sheets made with two different types of GO solution on the performance of Si-based solar cells. Large-sized reduced GO (rGO) with an in-plane crystalline diameter of 3.42 nm has smaller defect sites and thus the Si/rGO Schottky junction solar cell shows a lower leakage current than the solar cell with small-sized rGO (i.e. an in-plane crystalline diameter of 3.03 nm). Enhanced open-circuit voltage ( V oc ) and improved short-circuit current ( J sc ) are observed for the solar cell with large-sized rGO due to the increased work function and Schottky barrier height at the Si and rGO junction. In other words, an increased built-in potential and a wider depletion region of the solar cell with large-sized rGO contribute to the increased carrier absorption and generation. These findings indicate that (i) rGO acts as a good transparent conducting layer and hole-transporting layer, and (ii) the control of rGO size in Si/rGO Schottky junction solar cell is important to improve the performance. [ABSTRACT FROM AUTHOR]

Background. Phlegm pattern questionnaire (PPQ) was developed to evaluate and diagnose phlegm pattern in Korean Medicine and Traditional Chinese Medicine, but it was based on a dataset from patients who visited the hospital to consult with a clinician regarding their health without any strict exclusion or inclusion. In this study, we reinvestigated the construct validity of PPQ with a new dataset and confirmed the feasibility of applying it to a healthy population. Methods. 286 healthy subjects were finally included and their responses to PPQ were acquired. Confirmatory factor analysis (CFA) was conducted and the model fit was discussed. We extracted a new factor structure by exploratory factor analysis (EFA) and compared the two factor structures. Results. In CFA results, the model fit indices are acceptable (RMSEA = 0.074) or slightly less than the good fit values (CFI = 0.839, TLI = 0.860). Many average variances extracted were smaller than the correlation coefficients of the factors, which shows the somewhat insufficient discriminant validity. Conclusions. Through the results from CFA and EFA, this study shows clinically acceptable model fits and suggests the feasibility of applying PPQ to a healthy population with relatively good construct validity and internal consistency. [ABSTRACT FROM AUTHOR]

Introduction: Coupling motions (CMs) are the motions occurring in different directions around the primary motion. As low back pain (LBP) is known to be associated with lumbar CMs, some studies measured lumbar CMs using the microelectromechanical system inertial measurement unit (MEMS-IMU) because of its low cost and small size. This study aimed to examine the reliability of lumbar CM measurements using the MEMS-IMU and to classify the individual characteristics of lumbar CMs. Methods: MEMS-IMUs were attached to the two lumbar points (L, L) of 19 male volunteers (age, 24.3 ± 1.2 years). Following an instructional video and audio recording, they conducted the six lumbar movements three times: flexion and extension, left and right lateral bending, and left and right rotation. The six lumbar movements were repeated after 1 h. Raw data were transformed into angle data using MATLAB. Intraclass correlation coefficients (ICCs) were calculated to evaluate intratest repeatability and test-retest reliability. Finally, angle data were analyzed to examine whether individual characteristics of lumbar CMs could be identified. Results: Lumbar CM measurements showed fair to good or excellent intratest repeatability and test-retest reliability, ranging from 0.669 to 0.997 of the ICCs. All lumbar CMs could be categorized into six types, and flexion and extension CMs were more prominent than other CMs. Conclusions: Lumbar CM measurements obtained using the MEMS-IMU are reliable, and identifying the individual variations of lumbar CMs may be helpful for alleviating chronic or recurrent LBP. [ABSTRACT FROM AUTHOR]

Carbon nanotube buckypaper has been considered as one of the promising candidates for chemiresistive sensor applications, especially with environmental monitoring purpose due to large surface area, device flexibility, and the broad spectrum of responsive chemical vapor molecules. However, one of typical drawbacks in carbon-based sensors is incomplete recovery to their initial state after chemical reactions with analytes, degrading sensing reproducibility. In this work, we present a thermally stable and robust boron nitride nanotube/carbon nanotube (BNCNT) hybrid paper for self-enhanced chemiresistive sensing with full reversibility. Boron nitride nanotube (BNNT) plays an essential role in long-term reliability (33 days) at the operating temperature of 200 °C. In addition, a finite-element method was applied to understand the thermal behavior of the BNCNT network structure. The BNCNT paper-based chemiresisitve sensor exhibited highly sensitive, selective, and fully reversible responses to NO 2 without external heating. Also, the sensor demonstrated the detection limit of parts per billion (ppb)-levels under strain with high reliability. With these remarkable strengths, significantly facile and cost-effective fabrication processes provide an environmental sensing platform for use in smart clothing with wearable electronics. • Boron nitride nanotube/carbon nanotube (BNCNT)-based chemiresistive sensor with full reversibility was developed. • The BNCNT paper exhibits a highly sensitive detection to NO 2 at room temperature. • The detection limit (DL) is 3.41 parts per billion (ppb) even under strained conditions with high reliability. • The BNCNT papers maintained its self-enhanced temperature of 200 °C during a long-term stability test for 33 days. • The BNNT plays a major role in the long-term reliability of maintaining a temperature of CNT networks. [ABSTRACT FROM AUTHOR]

If a small dc-link capacitor is used in the dc link fed by a single-phase ac source, then the dc-link voltage severely fluctuates at twice of the source frequency. To handle this fluctuation, the concept of “average voltage constraint” is proposed in this study. On the basis of this concept, a flux-weakening scheme, generating the d-axis current reference (ids^{r}^{\ast}) for the interior permanent-magnet synchronous machine, is devised. The q-axis current reference (iqs^{r}^{\ast}) is modified for the unity power factor operation in the viewpoint of an ac source without an additional sensor. The proposed scheme has been applied to the inverter-driven 1-kW compressor of an air conditioner. From the experimental results, it has been verified that the compressor operates well at the required operating condition, regardless of the severe fluctuation of dc-link voltage, because of the reduced dc-link capacitance. The frequency spectrum of the ac source current reveals that the harmonics of the source current meet the regulation of IEC 61000-3-2 Class A and that the overall power factor is above 96% without any additional circuit, such as an input filter and a power factor correction circuit. [ABSTRACT FROM PUBLISHER]

Abstract: Graphene oxide coated on GaN was simultaneously reduced and doped with nitrogen via excimer laser irradiation. Nitrogen dopant was originated from the GaN during the laser-induced dissociation at high energies. This phenomenon was confirmed by the absence of C–N bond formation in laser irradiated graphene oxide on SiO2. A top-gated field-effect transistor based on laser reduction of graphene oxide channel on GaN showed n-type behavior via the gate voltage modulation. The present findings indicate a paradigm for the formation of graphene-nitride semiconductor interfaces. [Copyright &y& Elsevier]

Extracting useful and meaningful patterns from large volumes of text data is of growing importance. In the present study we analyze vast amounts of prescription data, generated from the book of oriental medicine to identify the relationships between the symptoms and the associated medicines used to treat these symptoms. The oriental medicine book used in this study (called Bangyakhappyeon) contains a large number of prescriptions to treat about 54 categorized symptoms and lists the corresponding herbal materials. We used an association rule algorithm combined with network analysis and found useful and informative relationships between the symptoms and medicines. [ABSTRACT FROM AUTHOR]

Abstract: We report on the formation and optimization of undercut-microholes (UM) generated by a wet etching process. GaN epilayers with 6μm and 15μm polygonal holes (PH) were grown by using selective metal organic chemical vapor deposition under identical growth conditions. The samples were wet etched with either a KOH solution or a mixed H3PO4:H2SO4 solution. Both kinds of etching solution produced the formation of UM. In the case of the etching produced with the mixed H3PO4:H2SO4 solution, the angle of UM was varied with an increase of H2SO4 in the solution. The etching produced by the KOH solution was very simple, and it formed a clear UM with an angle of 62°. This was achieved without etching the hard mask because of the selective etching and crystallographic characteristics of the GaN. UM were optimized through etching with PH structures, and the results showed formation of clear UM in a 15μm PH structure. [Copyright &y& Elsevier]

Abstract: This paper reports on the deflection effect of ellipsoidal air tunnel (EAT) array as an embedded deflector with low refractive index in InGaN/GaN light-emitting diodes (LEDs). Light extraction efficiency (LEE) for different height-to-width (h/w) ratios of air structure is analyzed by using an optical simulation program. Maximum LEE was obtained at a h/w ratio of 0.3, which corresponds to an ellipsoidal shape of the air structure. An LED structure with EAT array embedded between the sapphire substrate and the GaN epitaxial layer has been fabricated. The reflectance spectra measured over the entire visible spectral range showed reflectance modulations by the EAT structures. Moreover, the light-output power of the EAT-embedded LED was enhanced by 2.3times compared to a conventional LED without EAT arrays. This could be attributed to the enhanced light deflection from EAT structures. [Copyright &y& Elsevier]

Abstract: We fabricated GaN-based light-emitting diodes (LEDs) with a transparent ohmic contact made from nanoporous indium tin oxide (ITO). The nanoporous structures are easily made and controlled using a simple wet etching technique. The transmittance, sheet resistance, and root-mean-square surface roughness of the nanoporous ITO films are correlated strongly with the etch times. On the basis of the experimental values of these parameters, we choose an optimum etch time of 50s for the fabrication of LEDs. The wall-plug efficiency of the LEDs with nanoporous ITO is increased by 35% compared to conventional LEDs at an injection current of 20mA. This improvement is attributed to the increase in light scattering at the nanoporous ITO film-to-air interface. [Copyright &y& Elsevier]

Abstract: In prion diseases, metal imbalances in brain and/or metal substitutions for copper in prion protein suggest that metal-catalyzed oxidation (MCO) and oxidative stress may affect cellular function and accumulation of protease-resistant prion protein (PrPSc). We examined the effect of metal-induced oxidative stress by Fenton reaction on prion protein with regard to its degradation, insolubility, and infectivity. Precipitation and insolubility of prion protein were induced by Fenton reaction in scrapie-infected brain homogenate. Results showed an increase in hydroxylation products (thiobarbituric acid reactive substances; TBARS) and a decrease of ferrous ion (Fe2+) levels after Fenton reaction. Efficiency of metal-induced oxidation was higher for Fe2+ than Mn2+. Compared to untreated samples, there was increased susceptibility to proteolytic degradation of PrPSc after treatment with 3.12–12.5 mM Fe2+–Mn2+/H2O2. Interestingly, we observed that Fenton reaction could extend incubation periods, indicating a decrease in scrapie infectivity. These results suggest that PrPSc hydroxylation and degradation may affect PrP conversion and the pathogenesis of prion diseases. [Copyright &y& Elsevier]

Abstract: The annual gametogenesis of Yezo scallop, Patinopecten yessoensis, raised in suspended-hanging (SHCS) and bottom-sowing culture systems (BSCS) on the east coast of Korea was investigated over 2 years. Gametogenesis was initiated in October, when the surface water temperature reached 18 °C. The gametes matured fully and were ready for spawning in March and early April. Spawning occurred from late March to late May, when the water temperature rose from 7 °C to 11 °C. The gonado-somatic index (GSI), a ratio of gonad weight to total tissue weight, ranged from 3.05 (September) to 23.11 (April) for SHCS scallops and from 3.02 (August) to 20.30 (April) for BSCS scallops. The GSI of SHCS scallops was significantly higher (P <0.05) than that of BSCS scallops during the first reproductive season, but not the next spawning season. SHCS scallops also maintained a significantly higher condition factor (CF) than that of BSCS scallops (P >0.05) throughout most of the period, indicating that the SHCS may provide better growth and reproductive conditions. The higher GSI of SHCS scallops in the first spawning season may have resulted from different levels of food availability and the stocking size of the spats. [Copyright &y& Elsevier]

The mechanism of cell death by pheophorbide a (Pba) which has been established to be a potential photosensitizer was examined in experimental photodynamic therapy (PDT) on Jurkat cells, a human lymphoid tumor cell line. In 30–60 min after irradiation, Pba treated cells exhibited apoptotic features including membrane blebbing and DNA fragmentation. Pba/PDT caused a rapid release of cytochrome c from mitochondria into the cytosol. Sequentially, activation of caspase-3 and the cleavage of poly ADP-ribose polymerase (PARP) were followed. Meanwhile, no evidence of activation of caspase-8 was indicated in the cells. In experiments with caspase inhibitors, it was found that caspase-3 alone was sufficient initiator for the Pba-induced apoptosis of the cells. Pba specific emission spectra were confirmed in the mitochondrial fraction and the light irradiation caused a rapid change in its membrane potential. Thus, mitochondria were entailed as the crucial targets for Pba as well as a responsible component for the cytochrome c release to initiate apoptotic pathways. Taken together, it was concluded that the mode of Jurkat cell death by Pba/PDT is an apoptosis, which is initiated by mitochondrial cytochrome c release and caspase-3-pathways. [Copyright &y& Elsevier]

The efficacy of chlorophyll derivatives from silkworm excreta (CpD) in photodynamic antimicrobial chemotherapy (PACT) was studied. An enveloped animal virus, vesicular stomatitis virus (VSV), was used as a target organism. For CpD mediated PACT, the viruses in suspensions were treated with various doses of CpD (15–60 μg/ml) and visible red light was fixed at 120 mJ/cm2. The antiviral effect of the CpD-PACT was measured 1 h after light irradiation by the extent of suppression of plaque forming units (pfu). In cultures inoculated with PACT-treated VSV, suppression of pfu was prominent and the results were demonstrated in a dose-dependent manner. In assays of RT-PCR, a single dose of 30 μg/ml CpD and light caused complete inhibition of viral RNA synthesis in the host cells, which agreed with the complete loss of plaque forming activity observed in pfu assays. An in vitro transcription assay for viral RNA using [3H]UTP and gel electrophoresis for the level of M protein was conducted. A gradual decrease in viral RNA transcription and an immediate decrease in M protein levels were observed in cells inoculated with the CpD-PACT-treated virus. These results demonstrated that CpD is a potential photodynamic antiviral agent, which causes inactivation of the matrix protein as well as transcription mechanisms involved in VSV replication. [Copyright &y& Elsevier]

There is an error in of in the TE01 optical mode profile. The error is due to the author forgetting to rescale the x-axis when plotting the optical mode profile on the right y-axis. This oversight occurred because the optical mesh is different from the electrical mesh, and the correct figure is shown below. We wish to emphasize that this was merely a plotting error, and hence all of the results and conclusions presented in the manuscript remain unchanged. We sincerely regret the error. [ABSTRACT FROM AUTHOR]