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Background: Remimazolam, a newer benzodiazepine that targets the GABAA receptor, is thought to allow more stable blood pressure management during anesthesia induction. In contrast, propofol is associated with vasodilatory effects and an increased risk of hypotension, particularly in patients with comorbidities. This study aimed to identify medications that can maintain stable vital signs throughout the induction phase. Methods: We conducted a single-center, two-group, randomized controlled trial to investigate and compare the incidence of hypotension between remimazolam- and propofol-based total intravenous anesthesia (TIVA). We selected patients aged between 19 and 75 years scheduled for neurosurgery under general anesthesia, who were classified as American Society of Anesthesiologists Physical Status I–III and had a history of hypertension. Results: We included 94 patients in the final analysis. The incidence of hypotension was higher in the propofol group (91.3%) than in the remimazolam group (85.4%; P = 0.057). There was no significant difference in the incidence of hypotension among the various antihypertensive medications despite the majority of patients being on multiple medications. In comparison with the propofol group, the remimazolam group demonstrated a higher heart rate immediately after intubation. Conclusions: Our study indicated that the hypotension incidence of remimazolam-based TIVA was comparable to that of propofol-based TIVA throughout the induction phase of EEG-guided anesthesia. Both remimazolam and propofol may be equally suitable for general anesthesia in patients undergoing neurosurgery. Trial registration: Clinicaltrials.gov (NCT05164146). [ABSTRACT FROM AUTHOR]

Anode‐less all‐solid‐state batteries (ASSBs) are being targeted for next‐generation electric mobility owing to their superior energy density and safety as well as the affordability of their materials. However, because of the anode‐less configuration, it is nontrivial to simultaneously operate the cell at room temperature and low pressure as a result of the sluggish reaction kinetics of lithium (de)plating and the formation of interfacial voids. This study overcomes these intrinsic challenges of anode‐less ASSBs by introducing a dual thin film consisting of a magnesium upper layer with a Ti3C2Tx MXene buffer layer underneath. The Mg layer enables reversible Li plating and stripping at room temperature by reacting with Li via a (de)alloying reaction with a low reaction barrier. The MXene buffer layer maintains the electrolyte‐electrode interface by inhibiting the formation of voids even at low pressure of 2 MPa owing to the high ductility of MXene. This study highlights the importance of a combined chemical and mechanical approach when designing anode‐less electrodes for practical adaptation for anode‐less ASSBs. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the egress safety in nursing hospitals based on the capacity of the smoke exhaust system. To this end, the available safe egress time was calculated by analyzing changes in visibility, carbon monoxide, carbon dioxide, oxygen contents, and temperature depending on the fire duration. In addition, an egress simulation was performed using the number of workers (egress guides) and egress delay time as variables, and the required safe egress time was estimated. Based on the results, the egress safety of a prototype nursing hospital was evaluated. In this study, egress safety criteria to evaluate egress safety in a typical nursing hospital were presented, which are expressed in terms of normalized egress guides, the capacity ratio of the smoke exhaust system, and egress delay time. The proposed criteria can be used to evaluate the egress safety of typical nursing hospitals and to prepare complementary measures. [ABSTRACT FROM AUTHOR]

In this study, explainable models to predict the effective compressive strength of slab–column joints were proposed using genetic programming (GP). Effective compressive strength test results were collected from the literature, among which 81 were sandwich, corner, and edge columns, 44 were interior columns. With respect to the collected test results, random forest (RF), random forest–recursive feature elimination (RF‐RFE), K‐means clustering and linear regression analysis (KL) were applied to analyze the key features influencing the effective compressive strength. In addition, explainable models to predict the effective compressive strength were derived by using GP. The proposed models were verified by comparing with the existing equations, RF, and artificial neural network (ANN). Using the generative adversarial network (GAN), 20,000 fake data were additionally generated to strengthen the verification stage. The results showed that the proposed models exhibited the lowest root mean squared error (RMSE) among the existing equations, and RMSE of the proposed models was close to that of RF and ANN despite its conciseness. [ABSTRACT FROM AUTHOR]

In a post-tensioned precast concrete beam–column connection, the precast beams are post-tensioned to ensure the integrity of the connection and to provide recentring characteristics when the connection is subjected to seismic loads. In this study, the post-tensioned precast concrete beam–column connections were tested under reverse-cyclic loading with the test variables of grout strength at the beam–column interface and prestressing stress of stands. The test results showed that the post-tensioned precast concrete beam–column connections have a seismic performance equivalent to that of a conventional reinforced concrete beam–column connection. When high prestress is applied, however, confinement reinforcement is required at the beam ends to secure sufficient deformation capacity without crushing of concrete. An analysis model for post-tensioned precast concrete beam–column connections is also proposed; the model considers the bond properties of prestressing strands, and provides good agreement with the experimental results. [ABSTRACT FROM AUTHOR]

Huntington's disease (HD) is caused by a mutant huntingtin (mHtt) protein that contains abnormally extended polyglutamine (polyQ) repeats. The process of autophagy has been implicated in clearing mHtt aggregates, and microRNAs (miRNAs) have been reported as new players to regulate autophagy. However, the autophagy-associated target molecule of let7b miRNA remains unclear in HD. The present study showed that extended polyQ in mouse striatal neurons increased lysosomal membrane-associated protein 2A (LAMP2A) levels and influenced the inflammatory conditions, and these augmented levels correlated to the let7b miRNA expression level. The upregulated let7b increased LAMP2A and reduced the extended polyQ in mouse striatal cells. The let7b level was highly expressed in the striatum of pre-onset HD mice, whereas it was significantly reduced in the post-onset HD striatum. Considering the level changing pattern of let7b, LAMP2A protein levels were increased in the striatum of pre-onset HD mice, but decreased in the striatum of post-onset HD mice. These results suggest that LAMP2A related to chaperone-mediated autophagy (CMA) capacity might play an important role in HD symptom onset and progression. • Let7b miRNA was more highly expressed in the extended polyQ cells than in the normal cells. • Let7b level was highly expressed in the striatum of pre-onset HD mice but reduced in the post-onset HD striatum. • The upregulated let7b increased the levels of LAMP2A and reduced the extended polyQ in mouse striatal cells. • HD onset might be related to the reduced LAMP2A expression level in the striatum. [ABSTRACT FROM AUTHOR]

In this study, a total of six full‐scale sandwich columns were fabricated, and experiments on their load transfer performance were conducted. The effects of steel fiber reinforcement and the ratio of the column width to the slab thickness on the effective compressive strength were theoretically analyzed, and briefly compared the test results of full‐ and reduced‐scale specimens. The current design codes do not take into account the ratio of the column width to the slab thickness when estimating the effective compressive strengths of slabs and columns with different compressive strengths. The test results conducted in this study, however, showed that the effective compressive strength tended to decrease with increasing slab thickness. In addition, the specimen reinforced with steel fibers in the column region exhibited a higher effective compressive strength than the specimen with steel fibers in the slab region. [ABSTRACT FROM AUTHOR]

Porous carbon materials are promising candidates for anode materials in rechargeable potassium-ion batteries. However, their high surface area and low crystallinity usually cause side reactions with electrolytes and slanted charge/discharge profiles. Herein, we report the synthesis of porous carbon microspheres with highly graphitized structure and enhanced potassium-ion storage properties. The prepared carbon microspheres exhibit a low working potential of ~0.2 V, high Coulombic efficiency, and a stable reversible capacity of 292.0 mAh/g after 100 cycles, which is significantly higher than that of commercial graphite (137.5 mAh/g after 100 cycles). These desirable performances are attributed to the high crystallinity of carbon and its porous structure, which provide active sites for potassium-ion storage and alleviate the stress caused by the large volume change during the insertion and extraction of potassium ions. [ABSTRACT FROM AUTHOR]

In order to achieve a high rate silicon (Si) anode for lithium-ion batteries, a nanostructured Si@C@CNT composite with multistage conductive networks and interpenetrating voids is designed and fabricated by a spray drying approach, which could obviously improve the electronic/ionic conductivity, and effectively release the strain generated during Li+ intercalation/de-intercalation into/from Si, thereby leading to a high-rate (620 mA h g−1 at 7.5 A g−1) and stable Si anode. For actual applications, Si@C@CNT-PG (porous graphene) electrode has been built by simple mixing of the Si@C@CNT nanocomposite and home-made PG at the weight ratio of 2:8 as the active material, which exhibits the overwhelming electrochemical performances: the reversible capacity reaches 600 mAh g−1 at 4 A g−1; moreover, 80% of the initial capacity is still attained after charge/discharge at 800 mA g−1 for 200 times. A nanostructured Si@C@CNT nanocomposite with multistage conductive pathways and interpenetrating voids has been prepared for high-rate silicon anodes of lithium-ion batteries. Image 1 • A hierarchical Si@C@CNT nanocomposite with effective ionic/electronic transport. • A compacted Si@C@CNT nanocomposite with robust structure. • Enhanced performance due to the building of C@CNT network. • A high-rate anode consisting of Si@C@CNT nanocomposite and porous graphene. [ABSTRACT FROM AUTHOR]

The purpose of this randomised controlled study is to compare the haemodynamic changes and the degree of incisional bleeding after scalp infiltration of lidocaine and dexmedetomidine versus lidocaine and epinephrine for patients with hemi-facial spasm undergoing microvascular decompression. Fifty-two patients were injected with 5 mL of 1% lidocaine with either dexmedetomidine (2 μg/mL) or epinephrine (1:100,000 dilution) to reduce scalp bleeding. Mean blood pressure and heart rate were recorded every minute for 15 minutes after scalp infiltration. The primary outcome was the incidence of predefined hypotension, which was treated with administration of 4 mg ephedrine as often as needed. The number of administrations and total amount of ephedrine administered were also recorded as a measure of the severity of hypotension. The neurosurgeon scored incisional bleeding by numeric rating scale from 0 (worst) to 10 (best). The incidence of hypotension (68% vs. 34.8%, P = 0.02) and the frequency (P = 0.02) and total dose (P = 0.03) of ephedrine administered were lower in the dexmedetomidine group than in the epinephrine group. In addition, there was no difference in mean blood pressure between the two groups but heart rates were lower in the dexmedetomidine group (P = 0.01). Incisional site bleeding was better with epinephrine (median [interquartile range] of the numeric rating Score: 6 [4] in the dexmedetomidine group and 8 [2] in the epinephrine group; P < 0.001). The dexmedetomidine-lidocaine combination may be recommended as a substitute for epinephrine-lidocaine for scalp infiltration in neurosurgical patients, especially neurologically compromised patients. [ABSTRACT FROM AUTHOR]

A terahertz oscillator design with an emphasis on the output power performance is presented. The 270‐GHz oscillator fabricated using InP 250‐nm DHBT technology adopts a common‐base cross‐coupled configuration. The design focus is on the input varactor termination by utilizing simulated power and frequency load‐pull contours. The measurement results show an improved peak output power of 5.8 dBm with an outstanding power variation of only 0.8 dB while maintaining moderate frequency‐tuning range of 269‐278 GHz. [ABSTRACT FROM AUTHOR]

Background & Aims: The association between nonalcoholic fatty liver disease and lung function has not been fully examined. The aim of this study was to clarify the association between nonalcoholic fatty liver disease and lung function in general population by performing cross‐sectional and longitudinal analysis. Methods: Participants without hepatic and respiratory disease who underwent regular health exams including hepatic sonography and spirometry with at least 3 years' follow‐up were included. In cross‐sectional analysis, the association between nonalcoholic fatty liver disease and lung function at baseline was examined with multiple regression models. The longitudinal analysis was performed by mixed linear regression models with propensity score matching. Results: Of 11 892 eligible participants (mean age, 47.7 years; male, 47.2%), 3815(32.1%) had nonalcoholic fatty liver disease based on sonography. In cross‐sectional analysis, the nonalcoholic fatty liver disease group had lower adjusted forced expiratory volume in 1‐second (men, 3.52 vs 3.44 L, P < .001; women, 2.62 vs 2.45 L, P < .001) and forced vital capacity (men, 4.33 vs 4.24 L, P < .001; women, 3.11 vs 2.97 L, P < .001) than the control group. In longitudinal analysis, during the mean follow‐up period of 6.6 years, there were no significant differences in forced expiratory volume in 1‐second or forced vital capacity decline rates between two groups in the propensity score‐matched cohorts (n = 4558). However, those with high nonalcoholic fatty liver disease fibrosis score and fibrosis‐4 (men, −21.7 vs −27.4 mL/y, P = .001; women, −22.4 vs −27.9 mL/y, P = .016) showed significantly faster decline in forced vital capacity compared to those with low scores. Conclusions: Nonalcoholic fatty liver disease was associated with decreased lung function at baseline but was not associated with accelerated lung function decline in the propensity score‐matched cohort. However, hepatic fibrosis was significantly associated with rapid forced vital capacity decline. [ABSTRACT FROM AUTHOR]

In modern high-rise reinforced concrete buildings, high strength concrete (HSC) has been typically used for column members, while normal strength concrete (NSC) has been generally used for floor slabs. This study proposed a new analytic approach that can reasonably estimate the effective compressive strengths of corner and exterior column members intersected by lower strength concrete slabs. The proposed model was theoretically derived based on strain distributions and constraint conditions at an interface between column and slab members. In addition, the compressive strength test results of isolated, exterior, and corner columns intersected by lower strength concrete slabs reported in the existing literature were compared to the effective compressive strengths estimated by the proposed model. The proposed model provided good accuracy on the effective compressive strengths of the column members intersected by slabs cast with lower concrete compressive strengths. It was also shown that the proposed model successfully reflects the effects of the aspect ratio between the slab thickness and the column width on the effective compressive strengths of the test specimens and their failure modes that changed significantly according to the column–slab compressive strength ratio. [ABSTRACT FROM AUTHOR]

Advanced electrode materials have been intensively explored for next-generation lithium-ion batteries (LIBs), and great progresses have been achieved for many potential candidates at the lab-scale. To realize the commercialization of these materials, industrially-viable synthetic approaches are urgently needed. Spray pyrolysis (SP), which is highly scalable and compatible with on-line continuous production processes, offers great fidelity in synthesis of electrode materials with complex architectures and chemistries. In this review, motivated by the rapid advancement of the given technology in the battery area, we have summarized the recent progress on SP for preparing a great variety of anode and cathode materials of LIBs with emphasis on their unique structures generated by SP and how the structures enhanced the electrochemical performance of various electrode materials. Considering the emerging popularity of sodium-ion batteries (SIBs), recent electrode materials for SIBs produced by SP will also be discussed. Finally, the powerfulness and limitation along with future research efforts of SP on preparing electrode materials are concisely provided. Given current worldwide interests on LIBs and SIBs, we hope this review will greatly stimulate the collaborative efforts among different communities to optimize existing approaches and to develop innovative processes for preparing electrode materials. [ABSTRACT FROM AUTHOR]

TopBP1 has been identified as a direct activator of ATR and interacts with the Nbs1 subunit of the Mre11-Rad50-Nbs1 (MRN) complex in egg extracts in a checkpoint-regulated manner. In this study, we show that Mdc1 associates with both TopBP1 and Nbs1 in egg extracts and human cells. We cloned a cDNA encoding the full-length version of Xenopus Mdc1. The association between Mdc1 and TopBP1 involves the first pair of BRCT repeats in TopBP1. The N-terminal region (161–230) of Mdc1 is required for this binding. The interaction between Mdc1 and Nbs1 involves the two tandem BRCT repeats of Nbs1. Functional studies with mutated forms of Mdc1, TopBP1, and Nbs1 indicate that the BRCT-dependent association of these proteins is critical for a normal checkpoint response to DSBs. TopBP1 cannot interact with Nbs1 in Mdc1-depleted egg extracts, suggesting that Mdc1 connects TopBP1 and Nbs1 together. These findings suggest that Mdc1 is a crucial mediator of the DNA damage checkpoint response. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) carbon nanotube (CNT)-multicomponent metal oxide composite microspheres with non-aggregation characteristics are prepared using a simple one-pot spray pyrolysis process, applying water-soluble metal salt and oxidized CNT fibers. The hierarchical porous 3D structure of the CNT is formed by networking the flexible CNTs with a high aspect ratio during the drying stage of a droplet. Subsequently, the Zn and Ge salts are deposited over the CNTs to form the ZnO-CNT and GeO 2 -CNT composite microsphere. Decomposition of Zn and Ge salts into their respective oxides and the conversion reaction to form Zn 2 GeO 4 at 700 °C, produce the Zn 2 GeO 4 -CNT composite microsphere. The initial discharge capacities of the Zn 2 GeO 4 , Zn 2 GeO 4 -CNT, ZnO-CNT, and GeO 2 -CNT microspheres, at a current density of 1.5 A g −1 , are 1351, 1211, 1387, and 1631 mA h g −1 , respectively, and their discharge capacities at the 300 th cycle are 415, 762, 261, and 480 mA h g −1 , respectively. The CNT-Zn 2 GeO 4 composite microspheres, selected as the first target material, show electrochemical properties superior to those of the bare Zn 2 GeO 4 , CNT-ZnO, and CNT-GeO 2 composite microspheres. The synergetic effect of the multicomponent composition of Zn 2 GeO 4 and the CNT support result in excellent Li-ion storage properties of the Zn 2 GeO 4 -CNT composite microspheres. [ABSTRACT FROM AUTHOR]

Objective Colorectal adenoma and coronary atherosclerosis have similar risk factors. The aim of this study was to investigate the association between colorectal adenoma and coronary artery calcification (CAC), which is used as a surrogate marker for coronary atherosclerosis. Methods This is a cross-sectional study of 398 Koreans (290 males, mean age of 56.8 ± 8.1 years) who underwent CAC scoring by multi-slice computed tomography and colonoscopy on the same day as the screening examination. The CAC scores were divided into the following three categories according to severity: absent (CAC score = 0), mild (0 < CAC score ≤ 100), and moderate-to-severe CAC (CAC score > 100). Results Colorectal adenoma was detected in 149 (37.4%) subjects and was significantly associated with a CAC score of >0 (OR = 1.66, 95% CI = 1.05–2.64, P = 0.032), including both mild (OR = 1.80, 95% CI = 1.06–3.03, P = 0.029) and moderate-to-severe CAC (OR = 1.95, 95% CI = 1.05–3.63, P = 0.035), in multivariate analysis after adjusting for age, gender and other risk factors. The proportion of subjects with colorectal adenoma and advanced adenoma progressively increased with increasing CAC score (colorectal adenoma 28.9%–54.1%, P for trend < 0.001; advanced adenoma 7.0%–16.4%, P for trend = 0.026). Conclusion Colorectal adenoma is related to coronary artery calcification independent of traditional risk factors for asymptomatic Koreans. The prevalence of advanced adenoma is more common in individuals with severe coronary atherosclerosis. [ABSTRACT FROM AUTHOR]

In this work, we studied the influence of surface functionality of multi-walled carbon nanotubes (MWCNTs) on the mechanical properties of basalt fiber-reinforced composites. Acid and base values of the MWCNTs were determined by Boehm's titration technique. The surface properties of the MWCNTs were determined FT-IR, and XPS. The mechanical properties of the composites were assessed by measuring the interlaminar shear stress, fracture toughness, fracture energy, and impact strength. The chemical treatments led to a change of the surface characteristics of the MWCNTs and of the mechanical interfacial properties of MWCNTs/basalt fibers/epoxy composites. Especially the acid-treated MWCNTs/basalt fibers/epoxy composites had improved mechanical properties compared to the base-treated and non-treated MWCNTs/basalt fibers/epoxy composites. These results can probably be attributed to the improved interfacial bonding strength resulting from the improved dispersion and interfacial adhesion between the epoxy resin and the MWCNTs. [ABSTRACT FROM AUTHOR]

Masu salmon, Oncorhynchus masou masou , is an economically important fish species in the Far East and occurs in two life history forms: sea-run migratory (anadromous) and freshwater resident (non-anadromous). The non-anadromous form has recently become a popular freshwater food and game fish during a well-known Korean winter festival. However, the genetic background of this species remains largely unknown, partly due to a lack of molecular genetic markers. In this study, we developed new polymorphic microsatellite markers for masu salmon using next-generation sequencing technology. From 40 primer sets, 11 primer sets (27.5% of the primer sets selected) were successfully amplified with 106 alleles (range 2–9) in 64 individuals from different populations: two wild and one hatchery. Observed and expected heterozygosities ranged from 0.304 to 0.947 and 0.278 to 0.865, respectively. Significant departures from the Hardy–Weinberg equilibrium were detected for four markers (OMM11, OMM17, OMM28, and OMM33) in a single population. All pair-wise F ST values were highly significant between the wild and hatchery populations (range 0.084–0.183, P < 0.0001). We identified a set of robust microsatellite markers that worked well even in formalin-fixed samples, which will be suitable for biogeographical and population structure analyses of the masu salmon. [ABSTRACT FROM AUTHOR]

Multi-shell structured binary transition metal oxide powders with a Ni/Co mole ratio of 1:2 are prepared by a simple spray drying process. Precursor powder particles prepared by spray drying from a spray solution of citric acid and ethylene glycol have completely spherical shape, fine size, and a narrow size distribution. The precursor powders turn into multi-shell powders after a post heat-treatment at temperatures between 250 and 800 °C. The multi-shell structured powders are formed by repeated combustion and contraction processes. The multi-shell powders have mixed crystal structures of Ni 1− x Co 2 O 4− x and NiO phases regardless of the post-treatment temperature. The reversible capacities of the powders post-treated at 250, 400, 600, and 800 °C after 100 cycles are 584, 913, 808, and 481 mA h g −1 , respectively. The low charge transfer resistance and high lithium ion diffusion rate of the multi-shell powders post-treated at 400 °C with optimum grain size result in superior electrochemical properties even at high current densities. [ABSTRACT FROM AUTHOR]

Irinotecan, an analogue of camptothecin, is frequently used as a single agent or in combination with other anticancer drugs for the treatment of colorectal cancer. However, the drug resistance of tumors is a major obstacle to successful cancer treatment. In this study, we established that cells acquire chronic resistance to irinotecan. We profiled their differential gene expression using microarray. After gene ontology (GO) and KEGG pathway analysis of the microarray data, we specifically investigated whether Sestrin3 could decrease irinotecan resistance. Our results revealed that Sestrin3 enhanced the anticancer effect of irinotecan in vitro in LoVo cells that had acquired resistance to irinotecan. Irinotecan-resistant LoVo cells showed lower reactive oxygen species (ROS) production than their irinotecan-sensitive parental cells. ROS production was increased by Sestrin3 knockdown in irinotecan-resistant LoVo cells. Our results indicate that Sestrin3 might be a good target to develop therapeutics that can help to overcome resistance to irinotecan. [ABSTRACT FROM AUTHOR]

A novel anode material for sodium-ion batteries consisting of 3D graphene microspheres divided into several tens of uniform nanospheres coated with few-layered MoS2 by a one-pot spray pyrolysis process is prepared. The first discharge/charge capacities of the composite microspheres are 797 and 573 mA h g−1 at a current density of 0.2 A g−1. The 600th discharge capacity of the composite microspheres at a current density of 1.5 A g−1 is 322 mA h g−1. The Coulombic efficiency during the 600 cycles is as high as 99.98%. The outstanding Na ion storage properties of the 3D MoS2-graphene composite microspheres may be attributed to the reduced stacking of the MoS2 layers and to the 3D structure of the porous graphene microspheres. The reduced stacking of the MoS2 layers relaxes the strain and lowers the barrier for Na+ insertion. The empty nanospheres of the graphene offer voids for volume expansion and pathways for fast electron transfer during repeated cycling. [ABSTRACT FROM AUTHOR]

Composite powders of the configuration Si@carbon@void@graphene were prepared by a one-step spray pyrolysis process, by adding polyvinylpyrrolidone (PVP) to a precursor solution containing graphene oxide (GO) sheets and silicon nanoparticles (NPs). Morphological analysis indicates that the individual Si NPs are coated with amorphous carbon and encapsulated in a micrometer-sized graphene ball structure that offers a large amount of buffer space. The addition of PVP improves the stability of the colloidal spray solution containing the GO sheets and the Si NPs. Consequently, the prepared Si@C@void@graphene composite powders have a relatively more uniform morphology than the Si@void@graphene composite powders prepared from the spray solution without PVP. The first charge and discharge capacities of the Si@C@void@graphene electrode measured at 0.1 A g−1 are as high as 3102 and 2215 mA h g−1, respectively. With an increase in the current rate from 0.5 to 11 A g−1, 46 % of the original capacity (i.e., 2134 mA h g−1) is maintained. After 500 cycles at a high rate of 7 A g−1, the Si@C@void@graphene electrode shows 84 % capacity retention and 99.8 % of the average Coulombic efficiency. The superior cycling and rate capabilities of the prepared Si@C@void@graphene electrode could be attributed to the uniform carbon coating of the Si NPs and the graphene ball structure, which facilitates efficient diffusion of Li ions and prevents the penetration of electrolyte into graphene ball during cycling. [ABSTRACT FROM AUTHOR]

Fe 3 O 4 -decorated graphene balls were prepared by a spray pyrolysis process. Analysis by Raman spectroscopy and X-ray photoelectron spectroscopy indicated that the spray pyrolysis at 800 °C resulted in the complete reduction of graphene oxide sheets containing oxygen functional groups into graphene sheets, leading to the formation of Fe 3 O 4 -decorated graphene balls. The graphene content in the composite ball was 27 wt%. The Brunauer–Emmett–Teller surface area of the Fe 3 O 4 -decorated graphene balls was as high as 130 m 2 g −1 . The initial discharge and charge capacities of the Fe 3 O 4 -decorated graphene balls at a high current density of 7 A g −1 were 1210 and 843 mAh g −1 , respectively, and the discharge capacity was as high as 690 mAh g −1 even after 1000 cycles. The stable reversible discharge capacities of the Fe 3 O 4 -decorated graphene balls decreased from 1040 to 540 mAh g −1 with the increase in current density from 1 to 30 A g −1 . The Fe 3 O 4 -decorated graphene balls with a uniform distribution of ultrafine Fe 3 O 4 nanocrystals below 15 nm showed superior electrochemical properties as anode materials for lithium ion batteries. The overall structure of the Fe 3 O 4 -decorated graphene balls was maintained even after long-term cycling. [ABSTRACT FROM AUTHOR]

Hierarchically structured tin oxide/reduced graphene oxide (RGO)/carbon composite powders are prepared through a one-pot spray pyrolysis process. SnO nanoflakes of several hundred nanometers in diameter and a few nanometers in thickness are uniformly distributed over the micrometer-sized spherical powder particles. The initial discharge and charge capacities of the tin oxide/RGO/carbon composite powders at a current density of 1000 mA g−1 are 1543 and 1060 mA h g−1, respectively. The discharge capacity of the tin oxide/RGO/carbon composite powders after 175 cycles is 844 mA h g−1, and the capacity retention measured from the second cycle is 80 %. The transformation during cycling of SnO nanoflakes, uniformly dispersed in the tin oxide/RGO/carbon composite powder, into ultrafine nanocrystals results in hollow nanovoids that act as buffers for the large volume changes that occur during cycling, thereby improving the cycling and rate performances of the tin oxide/RGO/carbon composite powders. [ABSTRACT FROM AUTHOR]

A facile, one-pot method for synthesizing spherical- like metal sulfide-reduced graphene oxide (RGO) composite powders by spray pyrolysis is reported. The direct sulfidation of ZnO nanocrystals decorated on spherical-like RGO powders resulted in ZnS-RGO composite powders. ZnS nanocrystals with a size below 20 nm were uniformly dispersed on spherical-like RGO balls. The discharge capacities of the ZnS-RGO, ZnO-RGO, bare ZnS, and bare ZnO powders at a current density of 1000 mAg-1 after 300 cycles were 628, 476, 230, and 168 mAhg-1, respectively, and the corresponding capacity retentions measured after the first cycles were 93, 70, 40, and 21 %, respectively. The discharge capacity of the ZnS-RGO composite powders at a high current density of 4000 mAg-1 after 700 cycles was 437 mAhg-1. The structural stability of the highly conductive ZnS-RGO composite powders with ultrafine crystals during cycling resulted in excellent electrochemical properties. [ABSTRACT FROM AUTHOR]

Amorphous nickel oxide-carbon composite powders have been prepared using a facile spray-drying process. The nickel nitrate-citrate hydrate precursor powders were transformed into an amorphous NiO-carbon composite powder through a post-treatment at 250 °C for 1 h. The excellent supercapacitor performance of the amorphous NiO- carbon composite powder can be ascribed to the unique electrochemical behavior of the ultrafine amorphous NiO nanoclusters. [ABSTRACT FROM AUTHOR]

Macroporous Fe3O4/carbon composite and core-shell Fe3O4@carbon composite microspheres have been prepared by means of one-pot spray pyrolysis. The addition of polystyrene (PS) nanobeads to a spray solution containing an iron salt and poly(vinylpyrrolidone) (PVP) led to macroporous Fe3O4/carbon composite microspheres, the carbon and iron components of which are uniformly distributed over the entire composite microsphere. The pore-size distribution curve for the macroporous Fe3O4/carbon composite shows distinct peaks at around 10 and 80 nm. An electrode prepared from the macroporous Fe3O4/carbon composite microspheres showed better cycling and rate performances than an electrode formed from core-shell Fe3O4@carbon composite microspheres. The initial discharge and charge capacities of the macroporous Fe3O4/carbon composite microsphere electrode were determined to be 1258 and 908 mA h g−1 at 2 A g−1, respectively, and the corresponding initial coulombic efficiency was 72 %. The composite microsphere electrode cycled 500 times at 5 A g−1 showed a high discharge capacity of 733 mA h g−1. [ABSTRACT FROM AUTHOR]

MDC1, a mediator of DNA damage response, recruits other repair proteins on double-strand break (DSB) sites. MDC1 is necessary for activating checkpoint kinases Chk1 and Chk2. It is unclear whether Chk1 interacts with MDC1. MDC1 also comprises many discrete domains. The role of the proline-serine-threonine (PST)-repeat domain of MDC1 in the DNA damage response is unclear. Here, we showed that MDC1 directly binds Chk1 through this PST-repeat region. Phosphorylation of Chk1 by ionizing radiation (IR) also required this PST-repeat domain. Degradation of intact MDC1 was accelerated depending on the PST-repeat domain after IR exposure. In the IR damage response, the PST-repeat-deleted MDC1 levels remained elevated with slow degradation. This abnormal regulation of MDC1 was F-box- and WD40 repeat-containing 7 (FBXW7)-dependent. The mutation of lysine 1413 within the PST-repeat of MDC1 deregulated MDC1 with or without damage. K1413R mutant and PST-deleted MDC1 displayed reduced ability to repair the damaged genome post-IR exposure. These results provide that the PST domain of MDC1 is involved in Chk1 and DNA repair activation. The findings suggest new insights into how MDC1 connects the checkpoint and DNA repair in the DNA damage response. [ABSTRACT FROM AUTHOR]

Abstract: Graphene-MnO composite and hollow-structured MnO powders are prepared by a simple one-pot spray pyrolysis process. The graphene content in the graphene-MnO composite powder is estimated to be 10wt.%. The fine MnO crystals of size several tens of nanometers are uniformly distributed all over the graphene. The BET specific surface areas of the graphene-MnO composite and hollow-structured MnO powders are found to be 20 and 5 m2 g−1, respectively. The graphene-MnO composite powders have high initial discharge and charge capacities of 1207 and 849mA h g−1, respectively, at a current density of 500mAg−1. The initial discharge and charge capacities of the hollow-structured MnO powders are 1004 and 673mA h g−1, respectively. The discharge capacities of the graphene-MnO composite and hollow-structured MnO powders for the 130th cycle are 1313 and 701mA h g−1, respectively. [Copyright &y& Elsevier]

VO2-decorated reduced graphene balls were prepared by a one-pot spray-pyrolysis process from a colloidal spray solution of well-dispersed graphene oxide and ammonium vanadate. The graphene-VO2 composite powders prepared directly by spray pyrolysis had poor electrochemical properties. Therefore, the graphene-VO2 composite powders were transformed into a reduced graphene ball (RGB)-V2O5 (RGB) composite by post-treatment at 300 °C in an air atmosphere. The TEM and dot-mapping images showed a uniform distribution of V and C components, originating from V2O5 and graphene, consisting the composite. The graphene content of the RGB-V2O5 composite, measured by thermogravimetric analysis, was approximately 5 wt %. The initial discharge and charge capacities of RGB-V2O5 composite were 282 and 280 mA h g−1, respectively, and the corresponding Coulombic efficiency was approximately 100 %. On the other hand, the initial discharge and charge capacities of macroporous V2O5 powders were 205 and 221 mA h g−1, respectively, and the corresponding Coulombic efficiency was approximately 93 %. The RGB-V2O5 composite showed a better rate performance than the macroporous V2O5 powders. [ABSTRACT FROM AUTHOR]

A simple and general method for the large-scale production of yolk-shell powders with various compositions by a spray-drying process is reported. Metal salt/dextrin composite powders with a spherical and dense structure were obtained by spray drying and transformed into yolk-shell powders by simple combustion in air. Dextrin plays a key role in the preparation of precursor powders for fabricating yolk-shell powders by spray drying. Droplets containing metal salts and dextrin show good drying characteristics even in a severe environment of high humidity. Sucrose, glucose, and polyvinylpyrrolidone are widely used as carbon sources in the preparation of metal oxide/carbon composite powders; however, they are not appropriate for large-scale spray-drying processes because of their caramelization properties and adherence to the surface of the spray dryer. SnO2 yolk-shell powders were studied as the first target material in the spray-drying process. Combustion of tin oxalate/dextrin composite powders at 600 °C in air produced single-shelled SnO2 yolk-shell powders with the configuration SnO2@void@SnO2. The SnO2 yolk-shell powders prepared by the simple spray-drying process showed superior electrochemical properties, even at high current densities. The discharge capacities of the SnO2 yolk-shell powders at a current density of 2000 mA g−1 were 645 and 570 mA h g−1 for the second and 100th cycles, respectively; the corresponding capacity retention measured for the second cycle was 88 %. [ABSTRACT FROM AUTHOR]

A spray-pyrolysis process is introduced as an effective tool for the preparation of yolk-shell-structured materials with electrochemical properties suitable for anode materials in Li-ion batteries (LIBs). Yolk-shell-structured ZnO-Mn3O4 systems with various molar ratios of the Zn and Mn components are prepared. The yolk-shell-structured ZnO-Mn3O4 powders with a molar ratio of 1:1 of the Zn and Mn components are shown to have high capacities and good cycling performances. [ABSTRACT FROM AUTHOR]

In this study, we report the first preparation of phase-pure Co9S8 yolk-shell microspheres in a facile two-step process and their improved electrochemical properties. Yolk-shell Co3O4 precursor microspheres are initially obtained by spray pyrolysis and are subsequently transformed into Co9S8 yolk-shell microspheres by simple sulfidation in the presence of thiourea as a sulfur source at 350 °C under a reducing atmosphere. For comparison, filled Co9S8 microspheres were also prepared using the same procedure but in the absence of sucrose during the spray pyrolysis. The prepared yolk-shell Co9S8 microspheres exhibited a Brunauer-Emmett-Teller (BET) specific surface area of 18 m2 g−1 with a mean pore size of 16 nm. The yolk-shell Co9S8 microspheres have initial discharge and charge capacities of 1008 and 767 mA h g−1 at a current density of 1000 mA g−1, respectively, while the filled Co9S8 microspheres have initial discharge and charge capacities of 838 and 638 mA h g−1, respectively. After 100 cycles, the discharge capacities of the yolk-shell and filled microspheres are 634 and 434 mA h g−1, respectively, and the corresponding capacity retentions after the first cycle are 82 % and 66 %. [ABSTRACT FROM AUTHOR]

Li2TiO3–LiCrO2 cathode powders of various compositions are prepared by spray pyrolysis. Pure Li2TiO3 powder and Li2TiO3–LiCrO2 composite cathode powder have a spherical shape, nonaggregated structure, and fine sizes even after post-treatment at 700 °C under nitrogen atmosphere. The optimum post-treatment temperature to obtain composite powders with high initial discharge capacity, high coulombic efficiency, and good cycle properties is 700 °C. The initial charge capacities increase when the LiCrO2 content of the composite increase. However, the 0.55Li2TiO3–0.45LiCrO2 composite cathode powders have the highest initial discharge capacity of 203 mAh g−1, in which the capacity retention after 30 cycles is 96%. The dQ/dV curve of the first charge curve has a distinct oxidation peak at approximately 3.9 V, which corresponds to Cr oxidation. The oxidation peak shifts to a lower voltage range at approximately 3.6 V after the first cycling because an irreversible reaction takes place in the initial charge process. The composite cathode powders with low LiCrO2 content have low initial charge/discharge capacities and good cycle properties because of the stabilizing effect of high amounts of an inactive Li2TiO3 component. [ABSTRACT FROM AUTHOR]

Pure LiCoO2 nanopowders and those coated with lithium boron oxide (LBO) glass are prepared directly using high-temperature flame spray pyrolysis. Prior to post-treatment, the LiCoO2 powders with nanometer-size particles have low discharge capacities and poor cycle properties, irrespective of the amount of glass material. Post-treatment at 500 °C does not improve these properties significantly; however, the LBO glass-modified LiCoO2 powders post-treated at 600 and 700 °C demonstrates good cycle performance. The discharge capacity of the 5 wt% glass-modified LiCoO2 powders post-treated at 600 °C with a mean particle size of 120 nm, decreases from 122 to 109 mAh g−1 after 50 cycles, with a capacity retention of 89%. The capacity retentions of the pure and 2, 5, and 10 wt% glass-modified LiCoO2 powders post-treated at 700 °C are 86, 96, 98, and 98% after 50 cycles, respectively. [ABSTRACT FROM AUTHOR]

Charging up the batteries: The preparation and electrochemical properties of the yolk–shell LiV3O8 powders (see scheme) have been described for the first time. These powders have superior rate and cycling performances as a direct result of their unique particle structure and stability during cycling. [ABSTRACT FROM AUTHOR]

Herein, state-of-the-art research advances in South Korea regarding the development of chemical sensing materials and fully integrated Internet of Things (IoT) sensing platforms were comprehensively reviewed for verifying the applicability of such sensing systems in point-of-care testing (POCT). Various organic/inorganic nanomaterials were synthesized and characterized to understand their fundamental chemical sensing mechanisms upon exposure to target analytes. Moreover, the applicability of nanomaterials integrated with IoT-based signal transducers for the real-time and on-site analysis of chemical species was verified. In this review, we focused on the development of noble nanostructures and signal transduction techniques for use in IoT sensing platforms, and based on their applications, such systems were classified into gas sensors, ion sensors, and biosensors. A future perspective for the development of chemical sensors was discussed for application to next-generation POCT systems that facilitate rapid and multiplexed screening of various analytes. [ABSTRACT FROM AUTHOR]

This paper proposes an audio data augmentation method based on deep learning in order to improve the performance of dereverberation. Conventionally, audio data are augmented using a room impulse response, which is artificially generated by some methods, such as the image method. The proposed method estimates a reverberation environment model based on a deep neural network that is trained by using clean and recorded audio data as inputs and outputs, respectively. Then, a large amount of a real augmented database is constructed by using the trained reverberation model, and the dereverberation model is trained with the augmented database. The performance of the augmentation model was verified by a log spectral distance and mean square error between the real augmented data and the recorded data. In addition, according to dereverberation experiments, the proposed method showed improved performance compared with the conventional method. [ABSTRACT FROM AUTHOR]

Abstract: The preparation of precursors of BaTiO3 nanopowders with various amounts of Ag by spray pyrolysis is reported. The precursor powders obtained with hollow and thin-wall particles are composed of uniformly dispersed Ba, Ti, and Ag components. After post-treatment and a simple milling process, the precursor powders, irrespective of the amount of Ag, are transformed into Ag–BaTiO3 composite nanoparticles. The mean particle size of the Ag (10mol%)–BaTiO3 powders is 142nm. BaTiO3 pellets containing Ag exhibit dense structures even at a low sintering temperature of 1000°C. BaTiO3 pellets with 10mol% Ag show the highest dielectric constant of 2950, as opposed to the pure BaTiO3 pellets (without Ag), whose dielectric constant is 1827. [Copyright &y& Elsevier]

Abstract: Core–shell-structure Ag–BaTiO3 composite nanopowders are prepared directly by flame spray pyrolysis. The single-crystalline Ag was located in the core part of the composite powder, and the Ba and Ti components are uniformly distributed in the shell part. The X-ray diffraction (XRD) patterns of the Ag–BaTiO3 composite powders have the main crystal peaks of Ag and broad peaks at around 28°. The Ag–BaTiO3 pellets with low Ag contents (below 20 wt%) have a dense structure and fine grain size. Abnormal grain growth of the Ag(30 wt%)–BaTiO3 pellets occurs even at a low sintering temperature of 1000 °C. The Ag–BaTiO3 pellet had a mixed crystal structure of BaTiO3 and Ag phases. Silver is uniformly distributed in the BaTiO3 matrix without phase separation. The dielectric constants of the BaTiO3, Ag(10 wt%)–BaTiO3, and Ag(30 wt%)–BaTiO3 pellets are 830, 2130, and 4680, respectively. [Copyright &y& Elsevier]

Abstract: Nanometer-sized 0.6Li2MnO3·0.4LiNi0.5Mn0.5O2 composite cathode powders are prepared directly by high-temperature flame spray pyrolysis. The precursor powders and the powders post-treated at 800°C exhibit mixed-layered crystal structures comprising layered Li2MnO3 and layered LiNi0.5Mn0.5O2 phases. The discharge capacity of the precursor powders decreased from 193mAhg−1 to 96mAhg−1 by the 9th cycle, corresponding to a capacity retention of 49.7%. Post-treatment at 800°C increases the capacity retention of the post-treated composite powders to 94.6% after 50 cycles, corresponding to a decrease in the discharge capacity from 225 to 213mAhg−1. The post-treated composite powders that contain a high amount of the Li2MnO3 phase have a high initial discharge capacity and good cyclability. [Copyright &y& Elsevier]

Abstract: Spherically shaped 0.3Li2MnO3·0.7LiNi0.5Mn0.5O2 composite cathode powders with filled morphology and narrow size distribution are prepared by large-scale spray pyrolysis. A droplet classification reduces the standard deviation of the size distribution of the composite cathode powders. Addition of boric acid improves the morphological properties of the product powders by forming a lithium borate glass material with low melting temperature. The optimum amount of boric acid dissolved in the spray solution is 0.8wt% of the composite powders. The powders prepared from the spray solution with 0.8wt% boric acid have a mixed layered crystal structure comprising Li2MnO3 and LiNi0.5Mn0.5O2 phases, thus forming a composite compound. The initial charge and discharge capacities of the composite cathode powders prepared from the 0.8wt% boric acid spray solution are 297 and 217mAhg−1, respectively. The discharge capacity of the powders decreases from 217 to 196mAhg−1 by the 30th cycle, in which the capacity retention is 90%. [Copyright &y& Elsevier]

A variety of fish species undergo an ontogenetic change in prey selectivity, and several potentially interacting factors, including nutrient requirement, microhabitat change, and foraging ability, may account for the occurrence of the shift. Here we examine the foraging ecology and ontogenetic diet shift of a micro-carnivorous goby, Pterogobius elapoides (serpentine goby), dominant component of fish assemblage in shallow rocky areas off the coast in Korea and Japan. Although most other gobies are primarily benthic carnivores, P. elapoides is a semipelagic fish; however, little is known about how those species change their foraging tactics with growth. In our diet analyses, the most common diet was pelagic copepods and benthic amphipods, and diet shift was observed from pelagic to benthic with growth. The ontogenetic diet shift seems to be the result of the preference for energetically more profitable prey in larger-size classes as well as the results of different prey availability due to among-habitat variation in diet. However, differential food preference does not appear to affect individual scope for searching food. Several factors such as predation pressures and interspecific resource partitioning might contribute to the changes in diet observed among size classes, which were included in our ongoing tests. [ABSTRACT FROM AUTHOR]

Abstract: Li2O–2B2O3 glass-modified LiMn2O4 cathode powders are prepared using spray pyrolysis. The powders with 1 and 5wt% glass material have a spherical shape, dense structure, and large grain size. The BET surface areas of LiMn2O4 powders with 0 and 1wt% glass material are 15.0 and 5.9m2 g−1, and their mean crystallite sizes are 29 and 49nm. The lithium boron oxide (LBO) glass material improves the cycle properties as well as the initial discharge capacities of the LiMn2O4 powders at a constant current density of 1C. The discharge capacity of LiMn2O4 powders without any glass material decreases from 116.3 to 92.6mAhg−1 after 100 cycles, the reduced capacity being 80% of the initial capacity. However, the discharge capacity of the LiMn2O4 powders with 1wt% glass material decreases from 131.0 to 113.2mAhg−1 after 100 cycles; thus, the capacity retention is 86% of the initial capacity. [Copyright &y& Elsevier]

Abstract: Nano-sized Ba0.7Sr0.3TiO3 powders are prepared by post-treatment of the precursor powders with hollow and thin wall structure at temperatures between 900 and 1100°C. Ethylenediaminetetraacetic acid and citric acid improve the hollowness of the precursor powders prepared by spray pyrolysis. The mean sizes of the powders post-treated at temperatures of 900, 1000 and 1100°C are 42, 51 and 66nm, respectively. The densities of the Ba0.7Sr0.3TiO3 pellets obtained from the powders post-treated at 900, 1000 and 1100°C are each 5.36, 5.55 and 5.38gcm−3 at a sintering temperature of 1300°C. The pellet obtained from the powders post-treated at 1000°C has higher maximum dielectric constant than those obtained from the powders post-treated at 900 and 1100°C. [Copyright &y& Elsevier]

Abstract: Nanosized BaO–B2O3–SiO2 glass powders are directly prepared by flame spray pyrolysis. The mean size of the BaO–B2O3–SiO2 glass powders with amorphous phase and spherical shape is 30nm. The effects of glass powders on the sintering characteristics of the BaTiO3 pellet formed from the nanosized BaTiO3 powders are investigated. The mean size and BET surface area of the BaTiO3 powders prepared by spray pyrolysis are 110nm and 9.1m2/g. The BaTiO3 pellet with glass additive has large grain size with several microns, dense structure and pure tetragonal crystal structure at a sintering temperature of 1000°C. The XRD pattern of the pellet has distinct split of (200) and (002) peaks at 2θ ≈44.95°. The dielectric constant of the pellet without glass additive is 2180. However, the dielectric constants of the pellets with 1, 3, 5 and 7wt% glass additive with respect to BaTiO3 are 2496, 2514, 2700 and 2225, respectively. [Copyright &y& Elsevier]

Abstract: The mechanism of neural activity detection using the surface plasmon resonance (SPR) phenomenon was theoretically explored in this paper. Investigating the mechanism of SPR neural recordings has been difficult due to the complex relationship between different physiological and physical processes such as excitation of a nerve fiber and coherent charge fluctuations on the metal surface. This paper examines how these different processes may be connected by introducing a set of compartmental theoretical models that deal with the molecular scale phenomena; Poisson–Boltzmann (PB) equation, which was used to describe the ion concentration change under the time varying electrostatic potential, Drude–Lorentz electron model, which was used to describe electron dynamics under the time varying external forces, and a Fresnel''s three-layered model, which expresses the reflectivity of the SPR system in terms of the dielectric constants. Each physical theoretical model was numerically analyzed using the finite element method (FEM) formulated for the PB equation and the Green''s method formulated for the Drude–Lorentz electron equation. The model predicts that the ionic thermal force originating from the opening of the K+ ion channel is fundamental for modifying the dipole moment of the gold''s free electron; thus, the reflectivity is changed in the SPR system. The discussion was done also on important attributes of the SPR signal such as biphasic fluctuation and the electrical noise-free characteristics. [Copyright &y& Elsevier]

A hybrid deterministic-stochastic algorithm combining the simplex method (SM) and a genetic algorithm (GA) was applied to the problem of extracting the optical and morphological properties of human skin (HSOMPs) from visual reflectance spectroscopy data. The results using the GA-SM hybrid algorithm adopting tournament selection and selecting new sets of HSOMPs were compared with those using other conventional optimization algorithms that have generally been used for the extraction of HSOMPs. Monte-Carlo simulation showed that the suggested GA-SM hybrid algorithm enhanced the stability of the inverse solutions and computational efficiency. [ABSTRACT FROM AUTHOR]

Abstract: We investigated the characteristics of transmitted light from propagating surface plasmons based on rectangular silver gratings. The results calculated by rigorous coupled-wave analysis presented that silver diffraction gratings can produce significant transmittance and conversion efficiency, comparable to the case of dielectric gratings. Especially, silver gratings optimized at a wide range of grating thickness and period may lead to an improved diffraction efficiency larger than 64%. Moreover, the effect of silver oxide layer on the transmittance was examined and a bimetallic structure with a thin gold coating was introduced to prevent an oxidation of silver substrates. As a practical sensor application, silver grating-based surface plasmon resonance (SPR) configuration showed an enhanced sensitivity associated with an increase of surface reaction area and strong excitations of local plasmon fields, outperforming a conventional thin-film-based SPR structure. [Copyright &y& Elsevier]