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Abstract A novel auxetic structure applicable to airless tire spokes is designed based on the primitive-type triply periodic minimal surface (P-TPMS) to have higher stiffness through deformation under compressive force. For becoming higher stiffness by deformation, an unit cell of auxetic structure is proposed and its characteristics according to design parameters are studied. Based on the parametric study, a rotated primitive-type auxetic structure (RPAS) is designed, and the deformative behaviors of an airless tire with the RPAS spokes are compared with a generally used honeycomb spoke. Simulation and experiment results show that the designed RPAS tire exhibits more stable behavior through higher rigidity depending on the deformation state when compressed on flat ground and obstacles. This variable stiffness characteristic of RPAS tires can be advantageous for shock absorption and prevention of large local deformations. Also, the manufacturability of the designed auxetic structure is evaluated using real rubber-based additive manufacturing processes for practical application in the tire manufacturing industry.

Physical activity has been considered an important non-medication intervention in preserving mnemonic processes during aging. However, how aerobic exercise promotes such benefits for human health remains unclear. In this study, we aimed to explore the neuroprotective and anti-inflammatory effects of aerobic exercise against lipopolysaccharide (LPS)-induced amnesic C57BL/6J mice and BV-2 microglial cell models. In the in vivo experiment, the aerobic exercise training groups were allowed to run on a motorized treadmill 5 days/week for 4 weeks at a speed of 10 rpm/min, with LPS (0.1 mg/kg) intraperitoneally injected once a week for 4 weeks. We found that aerobic exercise ameliorated memory impairment and cognitive deficits among the amnesic mice. Correspondingly, aerobic exercise significantly increased the protein expressions of FNDC5, which activates target neuroprotective markers BDNF and CREB, and antioxidant markers Nrf2/HO-1, leading to inhibiting microglial-mediated neuroinflammation and reduced the expression of BACE-1 in the hippocampus and cerebral cortex of amnesic mice. We estimated that aerobic exercise inhibited neuroinflammation in part through the action of FNDC5/irisin on microglial cells. Therefore, we explored the anti-inflammatory effects of irisin on LPS-stimulated BV-2 microglial cells. In the in vitro experiment, irisin treatment blocked NF-κB/MAPK/IRF3 signaling activation concomitantly with the significantly lowered levels of the LPS-induced iNOS and COX-2 elevations and promotes the Nrf2/HO-1 expression in the LPS-stimulated BV-2 microglial cells. Together, our findings suggest that aerobic exercise can improve the spatial learning ability and cognitive functions of LPS-treated mice by inhibiting microglia-mediated neuroinflammation through its effect on the expression of BDNF/FNDC5/irisin.

Plasmodium knowlesi is the only Plasmodium that causes zoonotic disease among the Plasmodium that cause infection in humans. It is fatal due to its short asexual growth cycle within 24 h. Lactate dehydrogenase (LDH), an enzyme that catalyzes the final step of glycolysis, is a biomarker for diagnosing infection by Plasmodium spp. parasite. Therefore, this study aimed to efficiently produce the soluble form of P. knowlesi LDH (PkLDH) using a bacterial expression system for studying malaria caused by P. knowlesi. Recombinant pET-21a(+)-PkLDH plasmid was constructed by inserting the PkLDH gene into a pET-21a(+) expression vector. Subsequently, the recombinant plasmid was inserted into the protein-expressing Escherichia coli Rosetta(DE3) strain, and the optimal conditions for overexpression of the PkLDH protein were established using this strain. We obtained a yield of 52.0 mg/L PkLDH from the Rosetta(DE3) strain and confirmed an activity of 483.9 U/mg through experiments. This methodology for high-efficiency PkLDH production can be utilized for the development of diagnostic methods and drug candidates for distinguishing malaria caused by P. knowlesi.

The present article introduces a strategy for controlling oxidation and reduction reactions within polymer electrolyte membrane (PEM) networks as a means of enhancing storage capacity through the complexation of dissociated lithium cations with multifunctional groups of the polymer network. Specifically, co-polymer networks based on polysulfide (PS) and polyoxide (PO) precursors, photo-cured in the presence of succinonitrile (SCN) and lithium bis(trifluoro methane sulfonyl imide) (LiTFSI) salt, exhibited ionic conductivity on the order of mid 10−4 S/cm at ambient temperature in the 30/35/35 (weight %) composition. Lithium titanate (LTO, Li4Ti5O12) electrode was chosen as an anode (i.e., a potential source of Li ions) against lithium iron phosphate (LFP, LiFePO4) cathode in conjunction with polysulfide-co-polyoxide dual polyelectrolyte networks to control viscosity for 3D printability on conformal surfaces of drone and aeronautic vehicles. It was found that the PS-co-PO dual network-based polymer electrolyte containing SCN plasticizer and LiTFSI salt exhibited extra storage capacity (i.e., specific capacity of 44 mAh/g) with the overall specific capacity of 170 mAh/g (i.e., for the combined LTO electrode and PEM) initially that stabilized at 153 mAh/g after 50th cycles with a reasonable capacity retention of over 90% and Coulombic efficiency of over 99%. Of particular interest is the observation of the improved electrochemical performance of the polysulfide-co-polyoxide electrolyte dual-network relative to that of the polyoxide electrolyte single-network.

Malaria is one of the most prevalent diseases worldwide with high incidence and mortality. Among the five species that can infect humans, Plasmodium ovale morphologically resembles Plasmodium vivax, resulting in misidentification and confusion in diagnosis, and is responsible for malarial disease relapse due to the formation of hypnozoites. P. ovale receives relatively less attention compared to other major parasites, such as P. falciparum and P. vivax, primarily due to its lower pathogenicity, mortality rates, and prevalence rates. To efficiently produce lactate dehydrogenase (LDH), a major target for diagnosing malaria, this study used three Escherichia coli strains, BL21(DE3), BL21(DE3)pLysS, and Rosetta(DE3), commonly used for recombinant protein production. These strains were characterized to select the optimal strain for P. ovale LDH (PoLDH) production. Gene cloning for recombinant PoLDH production and transformation of the three strains for protein expression were performed. The optimal PoLDH overexpression and washing buffer conditions in nickel-based affinity chromatography were established to ensure high-purity PoLDH. The yields of PoLDH expressed by the three strains were as follows: BL21(DE3), 7.6 mg/L; BL21(DE3)pLysS, 7.4 mg/L; and Rosetta(DE3), 9.5 mg/L. These findings are expected to be highly useful for PoLDH-specific diagnosis and development of antimalarial therapeutics.

Plasmodium vivax is the most widespread cause of malaria, especially in subtropical and temperate regions such as Asia-Pacific and America. P. vivax lactate dehydrogenase (PvLDH), an essential enzyme in the glycolytic pathway, is required for the development and reproduction of the parasite. Thus, LDH from these parasites has garnered attention as a diagnostic biomarker for malaria and as a potential molecular target for developing antimalarial drugs. In this study, we prepared a transformed Escherichia coli strain for the overexpression of PvLDH without codon optimization. We introduced this recombinant plasmid DNA prepared by insertion of the PvLDH gene in the pET-21a(+) expression vector, into the Rosetta(DE3), an E. coli strain suitable for eukaryotic protein expression. The time, temperature, and inducer concentration for PvLDH expression from this E. coli Rosetta(DE3), containing the original PvLDH gene, were optimized. We obtained PvLDH with a 31.0 mg/L yield and high purity (>95%) from this Rosetta(DE3) strain. The purified protein was characterized structurally and functionally. The PvLDH expressed and purified from transformed bacteria without codon optimization was successfully demonstrated to exhibit its potential tetramer structure and enzyme activity. These findings are expected to provide valuable insights for research on infectious diseases, metabolism, diagnostics, and therapeutics for malaria caused by P. vivax.

Dual drug delivery has become the choice of interest nowadays due to its increased therapeutic efficacy in targeting the tumor site precisely. As quoted in recent literature, it has been known to treat several cancers with an acute course of action. Even so, its use is restricted due to the drug’s low pharmacological activity, which leads to poor bioavailability and increases first-pass metabolism. To overcome these issues, a drug delivery system using nanomaterials which would not only encapsulate the drugs of interest but also carry them to the target site of action is needed. Given all these attributes, we have formulated dual drug-loaded nanoliposomes with cisplatin (cis-diamminedichloroplatinum(II) (CDDP)), an effective anti-cancer drug, and diallyl disulfide (DADS), an organosulfur compound derived from garlic. The CDDP and DADS-loaded nanoliposomes (Lipo-CDDP/DADS) exhibited better physical characteristics such as size, zeta potential, polydispersity index, spherical shape, optimal stability, and satisfactory encapsulation percentage. The in vitro anti-cancer activity against MDA-MB-231 and A549 cell lines revealed that Lipo-CDDP/DADS showed significant efficacy against the cancer cell lines, depicted through cell nucleus staining. We conclude that Lipo-CDDP/DADS hold exceptional pharmacological properties with better anti-cancer activity and would serve as a promising formulation to treat various cancers.

In this paper, we present experimental transmittance data at 0.75, 1, 2, 3, 4.5, 6, 10, 18, and 24 GHz from urban and rural environments. All measurements were performed under line-of-sight (LoS) conditions. Reach distances were extracted using the multifrequency alpha-beta-gamma model. Normalized individual and combined ratios were plotted against the frequencies and compared between the two environments. Although our data were obtained under LoS conditions, they can be used to predict the service area over a wide frequency range and establish a public policy for mobile communications.

In this study, we analysed the spatiotemporal characteristics of precipitation in Korea in connection with weakening of tropical cyclones (TCs) around the Korean Peninsula (32°–36° N, 122°–132° E) over the past 30 years (1979–2015). Weakened TCs were classified into two categories: TCs weakened to extratropical cyclones (WEC) and TCs weakened to tropical depressions (WTD). In WEC, precipitation was evenly distributed over all of the Korean Peninsula, with the greatest precipitation recorded on the southern coast. In WTD, the amount of precipitation was the greatest on the southern coast, while low precipitation was recorded in the central and inland areas of Korea. In Region 1 (Central Province, Jeollabuk-do, and the inland region of Gyeongsangbuk-do), greater precipitation was observed in WEC than in WTD. In Region 2 (Jeollanam-do, Gyeongsangnam-do, Southeast Gyeongsangbuk-do, and Jeju-do), little difference in precipitation was found between WEC and WTD. In WEC, potential vorticity developed in the upper-level troposphere with TCs approaching Korea along with a thermal trough in the lower-level troposphere to the northwest of the TCs. Meanwhile, an upper-level troposphere jet and a strong upper-level troposphere divergence region were observed to the northeast of the TCs. It was assumed that these meteorological factors had induced baroclinic disturbance and nondiabatic process, creating a wide precipitation area around the TCs. In contrast, in WTD, none of the intense potential vorticity, thermal trough, and upper-level troposphere jet was observed around the TCs. Consequently, only a narrow precipitation area was created around the TCs. The upper-level troposphere divergence region was relatively small, and no intense precipitation area was formed around the TCs.

This study investigated interdecadal variations in summer rainfall in central eastern China before and after the mid-1990s. The mean difference in rainfall between the two epochs (average rainfall in the 1981–1995 period: 5.0 mm day−1; average rainfall in the 1996–2010 period: 6.0 mm day−1) was significant at the 95% confidence level. This study explored the cause of the recent increase in summer rainfall in central eastern China by analyzing the difference in average rainfall between 1996–2010 (hereafter, Epoch II) and 1981–1995 (hereafter, Epoch I). Analysis of rainfall revealed that positive anomalies were observed in a southwest–northeast direction across the south-central region of eastern China, Korea, and Japan, while negative anomalies were observed at latitudes of 40–50°N and in most areas in the western North Pacific region. These findings suggest that summer rainfall in central eastern China is part of East Asian summer monsoons and have an out-of-phase relationship with western North Pacific monsoons. To identify the cause of the recent increase in summer rainfall in central eastern China, the difference in 850 hPa stream functions between Epoch II and Epoch I was analyzed. This study found that anomalous huge anticyclonic circulations were strengthened in the western North Pacific region and anomalous cyclonic circulations were strengthened in the south-central region of eastern China. As a result, anomalous northeasterlies originating from anomalous cyclones centered on Lake Baikal and anomalous southerlies originating from anomalous cyclones in the south-central area of eastern China joined in central eastern China. The typical anomalous atmospheric circulations in the negative Pacific Decadal Oscillation (PDO) phase and the average PDO index and summer rainfall in central eastern China from June to August exhibited a high negative correlation, which was presumed to have been present since the previous winter.

Correlations between the South China Sea summer (June-September) monsoon (SCSSM) and El Niño Southern Oscillation (ENSO) for the past 32 years (1979–2010) were analyzed. As a result, a higher (lower) SST in the Niño-3.4 areas was associated with a weaker (stronger) SCSSM intensity. To examine the cause of this correlation, the differences between the June-September average of 8 El Niño years and the June-September average of 8 La Niña years were analyzed. Differences in the 850 hPa stream flows between the two groups found that anomalous huge cyclones existed in the subtropical Pacific regions of both hemispheres, which reinforced cold and dry anomalous northerlies in the SCS and anomalous westerlies from the Maritime Continent (MC) to the coastal waters of Chile. An analysis of the differences in the 200 hPa stream flows between the two groups found an anomalous pressure system pattern that was opposite to the result of the analysis of the differences in the 850 hPa stream flows between the two groups. Anomalous anticyclones existed in the subtropical Pacific of both hemispheres, which reinforced the anomalous easterlies from the MC to the equatorial central Pacific. When the anomalous atmospheric circulations of the upper and lower layers of the troposphere were also considered, the structure of anomalous atmospheric circulations in which the air current that rose in the equatorial central and eastern Pacific fell down in the MC. This indicates weakening of the Walker Circulation and a typical structure of atmospheric circulations that appears in El Niño years.

Conventional additive manufacturing processes are generally inadequate for printing electronics on a curved surface. When printing a curved functional structure, the typical way of generating the extrusion path only in a horizontal plane could cause various issues such as impreciseness and disconnect in the printed part. In this work, conformal 3D printing of a soft tactile sensor is presented in which curvilinear extrusion paths were generated for the printing of a curved sensor. An extrusion-based multi-material direct printing system was employed to print the sensor, and ultraviolet light was used to polymerize the printed layers. An ionic liquid–based pressure-sensitive polymer membrane, carbon nanotube-based conductive electrodes, and a soft polymeric insulation layer were conformally 3D printed to fabricate the curved sensor on a fingertip model. The conformally printed sensor was evaluated under different conditions. Sensors 3D-printed using conformal and planar slicing processes were compared to investigate the effect of curvilinear slicing on the printed parts. The results show that conformal 3D printing is able to overcome the fabrication limitations of conventional planar processing while also retaining the functionality of the printed structures.

Abstract Background Despite evidences of breastfeeding for preventing acute physical illnesses in infants, the evidence for the association between breastfeeding and long-term cognitive development is not yet convincing. Methods The data of nationwide representative sample of 1752 children born between 2008 and 2009 in Korea were prospectively assessed from the fetal period to examine the benefits of breastfeeding and cognitive development. Breastfeeding duration was prospectively assessed by parents. The Korean Ages and Stages Questionnaire and the Korean version of Denver II were used to assess early development annually from 5.5 to 26.2 months of age. Language development at 3 years of age was assessed with Receptive and Expressive Vocabulary Tests. Cognitive function at 8 years of age was assessed using multifactorial intelligence test. Results In the analysis of categorical variables, children who were breastfed for > 1 and ≤ 3 months displayed significantly higher odds ratios for delayed development assessed with Korean Ages and Stages Questionnaire at 14.1 months than those breastfed for > 3 and ≤ 6 months (OR = 2.21; 95% CI: 1.08, 4.50), but no significant differences in other rounds of assessments. In the analysis with continuous variables, there were significant differences among six groups of breastfeeding duration in communication (F = 3.72; p 3 months scored significantly higher on the communication (F = 17.71; p 3 months. Although these results are supported by previous studies, it is important to note that other factors were reported as larger determinants of cognitive development than breastfeeding. Future studies that examine the underlying mechanism for the association between breastfeeding and cognitive development are warranted.

Abstract Background Lead is known to be associated with attention-deficit/hyperactivity disorder (ADHD) even at low concentrations. We aimed to evaluate neurocognitive functions associated with lead in the blood and the interactions between lead and dopaminergic or noradrenergic pathway-related genotypes in youths with ADHD. Methods A total of 259 youths with ADHD and 96 healthy controls (aged 5–18 years) enrolled in this study. The Korean Kiddie Schedule for Affective Disorders and Schizophrenia–Present and Lifetime version was conducted for psychiatric diagnostic evaluation. Blood lead levels were measured, and their interaction with dopaminergic or noradrenergic genotypes for ADHD; namely, the dopamine transporter (DAT1), dopamine receptor D4 (DRD4), and alpha-2A-adrenergic receptor (ADRA2A) genotypes were investigated. All participants were assessed using the ADHD Rating Scale-IV (ADHD-RS). Participants also completed the continuous performance test (CPT) and Stroop Color-Word Test (SCWT). Analysis of covariance was used for comparison of blood lead levels between ADHD and control groups. A multivariable linear regression model was used to evaluate the associations of blood lead levels with the results of ADHD-RS, CPT, and SCWT; adjusted for intelligence quotient (IQ), age, and sex. A path analysis model was used to identify the mediating effects of neurocognitive functions on the effects of blood lead on ADHD symptoms. To evaluate the effect of the interaction between blood lead and genes on neuropsychological functions, hierarchical regression analyses were performed. Results There was a significant difference in blood lead levels between the ADHD and control groups (1.4 ± 0.5 vs. 1.3 ± 0.5 μg/dL, p = .005). Blood lead levels showed a positive correlation with scores on omission errors(r = .158, p = .003) and response time variability (r = .136, p = .010) of CPT. In the multivariable linear regression model, blood lead levels were associated with omission errors (B = 3.748, p = .045). Regarding the effects of lead on ADHD symptoms, hyperactivity-impulsivity was mediated by omission errors. An interaction effect was detected between ADRA2A DraI genotype and lead levels on omission errors (B = 5.066, p = .041). Conclusions Our results indicate that neurocognitive functions at least partly mediate the association between blood lead levels and ADHD symptoms, and that neurocognitive functions are affected by the interaction between blood lead levels and noradrenergic genotype.

Abstract:: Additive manufacturing of ceramics stands to transform applications requiring wear resistance in severe environments (including high temperatures and pressures, harsh chemicals, and biomedical implants, among many other uses). However, applications in electromagnetics are gaining increased attention as newly-available materials like zirconia provide very low electromagnetic loss and also provide the highest permittivity possible in 3D printing with near full density. By 3D printing zirconia lattices, the density can be modulated spatially by varying strut and beam thicknesses at arbitrary positions (such as when following a spatial function). As the effective permittivity is related to the density, the speed of electromagnetic radiation (the speed of light, c) can be controlled in the 3D space. As a preliminary investigation to understand processing limits and mechanical performance, this effort has focused on evaluating the compression and flexural strength of both 3D printed solid and lattice structures with millimeter-scale unit cells post-processed with different conditions. Non-destructive computer tomography was included to identify and validate remediation of internal delamination with hot isostatic pressing. Although zirconia lattices fabricated with NanoParticle Jetting™ were relatively delicate, millimeter periodic features were possible and provided sufficient strength to maintain structural integrity for non-critical loading.

We report analysis of phosphatase activity and inhibition on droplet-based microfluidic chips. Phosphatases are such attractive potential drug targets because abnormal phosphatase activity has been implicated in a variety of diseases including cancer, neurological disorders, diabetes, osteoporosis, and obesity. So far, several methods for assessing phosphatase activity have been reported. However, they require a large sample volume and additional chemical modifications such as fluorescent dye conjugation and nanomaterial conjugation, and are not cost-effective. In this study, we used an artificial phosphatase substrate 3-O-methylfluorescein phosphate as a fluorescent reporter and dual specificity phosphatase 22. Using these materials, the phosphatase assay was performed from approximately 340.4 picoliter (pL) droplets generated at a frequency of ~40 hertz (Hz) in a droplet-based microfluidic chip. To evaluate the suitability of droplet-based platform for screening phosphatase inhibitors, a dose–response inhibition study was performed with ethyl-3,4-dephostatin and the half-maximal inhibitory concentration (IC50) was calculated as 5.79 ± 1.09 μM. The droplet-based results were compared to microplate-based experiments, which showed agreement. The droplet-based phosphatase assay proposed here is simple, reproducible, and generates enormous data sets within the limited sample and reagent volumes.

Abstract This study found that the passage frequency of tropical cyclones (TCs) affecting Korea has had negative correlations with the Pacific Decadal Oscillation (PDO) and the El Niño–Southern Oscillation (ENSO) since the early 1980s. To examine the actual combined effects of PDO and ENSO on the passage frequency of TCs affecting Korea, the positive PDO and ENSO years for 9 years and the negative PDO and ENSO years for 9 years were selected during the periods of 1951–1981 (pre‐1981) and 1982–2012 (post‐1981), and then the average difference between these two phases was analyzed. An analysis of anomalous stream flows at 500 hPa showed the formation of anomalous cyclonic circulations in an east‐to‐west direction from East Asia to the North Pacific both in the pre‐1981 and post‐1981 periods in the positive PDO and ENSO years. However, the anomalous cyclones in East Asia were stronger in the pre‐1981 period, whereas the anomalous cyclones in the North Pacific were stronger in the post‐1981 period. Consequently, China, Korea and the west of Japan were affected by strong anomalous northerlies in the pre‐1981 period, and the TC passage frequency was lower in these regions as a result. In the post‐1981 period, these countries were affected by anomalous northwesterlies or anomalous westerlies.

Abstract Background Medicinal plants represent a source of new drugs for the prevention and treatment of infectious diseases. Dendropanax morbifera Léveille is an economically and medicinally important subtropical tree that has various biological activities. However, its ability to affect immune responses in vivo is unknown. Hence, this study was designed to examine the immunomodulatory activity of fermented D. morbifera extract in BALB/c mice. Methods five-week-old female BALB/c mice were arranged in six groups and kept under a standard laboratory condition. Splenocyte counts were determined using the trypan blue dye exclusion method, and splenic lymphocyte proliferation was determined using concanavalin A and lipopolysaccharide (LPS). Flow cytometric analysis was performed to phenotype T-lymphocytes. Next, cytokine and immunoglobulin quantitation was performed using sandwich ELISA. Results The results showed an increase in spleen cells by 71 and 67% in mice treated with 125 and 250 mg/kg of D. morbifera, respectively. In addition, splenocyte proliferation was increased 58.7% in response to concanavalin A treatment, while LPS treatment induced a 73.3% increase in mice treated with 125 mg/kg. T-cell phenotypic analysis indicated that D. morbifera-treated groups showed higher CD8a+, CD11b and CD3+ T-cell expression. However, the treatment groups showed suppression of IL-1α, Il-1β and IL-4. In addition, the IgG super-family was downregulated in a dose-dependent manner by 4.5% up to 43.7%. Conclusions Taken together, we show that D. morbifera increases the number and proliferation of T- and B-lymphocytes. Moreover, these effects may play a role in boosting non-specific immunity, while suppressing proinflammatory cytokines and immunoglobulins after a single antigen exposure.

Using data of autumn (September–November) Palmer Drought Severity Index (PDSI) observed at 61 weather observation stations for 1974–2013 provided by Korea Meteorological Administration (KMA), the present study applies the statistical change-point analysis to the PDSI time-series in order to determine variability of autumn drought in Korea. The study result shows a trend that autumn drought in Korea has been weakened since 1998. This weakening trend is statistically significant at the 90% confidence level. Thus, a difference in autumn mean between 1998–2013 (PDSI: –1.6, which means ‘wetness’ condition) and 1974–1997 periods (PDSI: –0.6, which means ‘drought’ condition) is analyzed in order to determine the cause of the weakening of autumn drought in Korea in recent years. The analysis on 850 hPa stream flows shows that the Mascarene high (MH) is strengthened in the southeast sea of Madagascar and anomalous northeasterlies blown from this anomalous anticyclonic circulation are moved to the north along the eastern coast of Africa as the cross-equatorial flows and then move from India to the east towards the South China Sea (SCS) by the anomalous cyclone (Arabian low, AL) located in the south sea of the Arabian Peninsula. Then, the anomalous flows move to the north direction towards Korea and Japan by the anomalous anticyclone (western North Pacific subtropical high, WNPSH) located in the east of Japan and anomalous cyclone located in the East Asia continent thereby showing clear anomalous southerlies in those regions. The anomalous pressure system pattern of west low and east high type is a typical pressure system pattern revealed during summer in East Asia. That is, the anomalous southerlies played an important role in supplying warm and humid airs in the low latitude to mid-latitude regions in East Asia including Korea and Japan. In addition, the predictability for autumn drought in Korea is diagnosed using three anomalous pressure systems (MH, AL, WNPSH).

Study objectives: To examine the resting-state functional connectivity (FC) between subcortical regions in relation to whole-brain activity in patients with psychophysiological insomnia (PI) and changes following cognitive–behavioral therapy for insomnia (CBTi). Methods: The FC between subcortical seed regions (caudate, putamen, pallidum, amygdala, thalamus, and hippocampus) and whole-brain voxels were compared between the PI group (n=13, mean age: 51.0±10.2years) and good sleepers (GS, n=18, mean age: 42.7±12.3years). Also, in the PI group, FC was compared before and after 5weeks of CBTi. Results: Compared to the GS group, the PI group exhibited stronger FC between the thalamus and prefrontal cortex and between the pallidum and precuneus but weaker FC between the pallidum and angular gyrus, the caudate and orbitofrontal cortex, and the hippocampus and fusiform gyrus. After CBTi, the PI group exhibited decreased FC between the thalamus and parietal cortex, the putamen and motor cortices, and the amygdala and lingual gyrus, but increased FC between the caudate and supramarginal gyrus, the pallidum and orbitofrontal cortex, and the hippocampus and frontal/parietal gyri. Conclusions: The present findings demonstrate different FC in PI patients compared to GS and provide insight into the neurobiological rationale for CBTi. Keywords: Psychophysiological insomnia, Insomnia, Resting state, Functional magnetic resonance imaging, Cognitive–behavioral therapy, Functional connectivity

Abstract Psychophysiological insomnia (PI) includes arousal to sleep-related stimuli (SS), which can be treated by cognitive behavioral therapy for insomnia (CBT-I). The present study was an exploratory, prospective intervention study that aimed to explore brain response to visual SS in PI before and after CBT-I. Blood oxygen level dependent (BOLD) signal differences in response to SS and neutral stimuli (NS) were compared between 14 drug-free PI patients and 18 good sleepers (GS) using functional magnetic resonance imaging (fMRI). BOLD changes after CBT-I in patients were also examined. PI patients showed higher BOLD activation to SS in the precentral, prefrontal, fusiform, and posterior cingulate cortices before CBT-I. The increased responses to SS were reduced after CBT-I. The increased response to SS in the precentral cortex was associated with longer wake time after sleep onset (WASO), and its reduction after CBT-I was associated with improvements in WASO. Clinical improvements after CBT-I were correlated with BOLD reduction in the right insula and left paracentral cortex in response to SS. PI showed hyper-responses to SS in the precentral cortex, prefrontal cortex, and default mode network and these brain hyper-responses were normalized after CBT-I. CBT-I may exert its treatment effects on PI by reducing hyper-responses to SS in the precentral cortex and insula.

Abstract Nicotinamide adenine dinucleotide phosphate (NADPH) oxidases (Nox) are an important family of catalytic enzymes that generate reactive oxygen species (ROS), which mediate the regulation of diverse cellular functions. Although phagocyte Nox2/gp91phox is closely associated with the activation of host innate immune responses, the roles of Nox family protein during Toxoplasma gondii (T. gondii) infection have not been fully investigated. Here, we found that T. gondii-mediated ROS production was required for the upregulation of macrophage migration inhibitory factor (MIF) mRNA and protein levels via activation of mitogen-activated protein kinase and nuclear factor-κB signaling in macrophages. Interestingly, MIF knockdown led to a significant increase in the survival of intracellular T. gondii in bone marrow-derived macrophages (BMDMs). Moreover, Nox4 deficiency, but not Nox2/gp91phox and the cytosolic subunit p47phox, resulted in enhanced survival of the intracellular T. gondii RH strain and impaired expression of T. gondii-mediated MIF in BMDMs. Additionally, Nox4-deficient mice showed increased susceptibility to virulent RH strain infection and increased cyst burden in brain tissues and low levels of MIF expression following infection with the avirulent ME49 strain. Collectively, our findings indicate that Nox4-mediated ROS generation plays a central role in MIF production and resistance to T. gondii infection.

Abstract This study found that there is a significant negative correlation between summer drought in Korea, China and Japan and the frequency of tropical cyclone (TC) in the subtropical western North Pacific (SWNP) using effective drought index (EDI). The frequency of TCs that affect Korea is low (high) in a year of summer drought (non-drought). As a case study, in 1994 when there is extremely severe summer drought in Korea, there was high frequency of TCs while in 2003 when there was least severe summer drought, the frequency of TCs is the lowest. Changes in the anomalous secondary circulation, namely anomalous upward (downward) flow in the SWNP and anomalous downward (upward) flow in the mid-latitudes of East Asia, are one of the causes of drought (non-drought).

Human physiological systems have a major role in maintenance of internal stability. Previous studies have found that these systems are regulated by various types of interactions associated with physiological homeostasis. However, whether there is any interaction between these systems in different individuals is not well-understood. The aim of this research was to determine whether or not there is any interaction between the physiological systems of independent individuals in an environment where they are connected with one another. We investigated the heart rhythms of co-sleeping individuals and found evidence that in co-sleepers, not only do independent heart rhythms appear in the same relative phase for prolonged periods, but also that their occurrence has a bidirectional causal relationship. Under controlled experimental conditions, this finding may be attributed to weak cardiac vibration delivered from one individual to the other via a mechanical bed connection. Our experimental approach could help in understanding how sharing behaviors or social relationships between individuals are associated with interactions of physiological systems.

ABSTRACT: The present study verified that Korea landfalling tropical cyclone (TC) frequency was rapidly increased since 1981 through the statistical change-point analysis. The increase was due to the formation of anomalous southerlies around Korea from the low latitude ultimately because anomalous cyclone was strengthened in East Asia continent due to the movement of western North Pacific subtropical high (WNPSH) to the east whereas anomalous anticyclone was strengthened in the western North Pacific. The anomalous southerlies played a role in steering flow that moved TCs generated in the subtropical western North Pacific to Korea. In order to determine the cause of strengthening of anomalous cyclone in East Asia continent, a snow depth during the preceding spring (March-May) was analyzed. The analysis result showed that most regions in East Asia had lower snow depth than that before 1981. Thus, anomalous cyclone can be developed in the region during summer due to heating in East Asia continent, which was started from the preceding spring, thereby forming a steering flow of anomalous southerlies that can move TCs into Korea. Furthermore, a correlation analysis between Pacific Decadal Oscillation (PDO) and Korea landfalling TC frequency verified that negative correlation was somewhat stronger after 1981. Keywords: Korea, tropical cyclone, statistical change-point analysis, snow depth, Pacific Decadal Oscillation

ABSTRACT: A seasonal probability prediction model for tropical cyclone (TC) genesis in the western North Pacific (5°-25°N, 110°-180°E) was developed using a simple logistic regression method. The predictors used in this model were total five: 850 hPa relative vorticity, 200-850 hPa vertical wind shear, 600 hPa relative humidity, 300 hPa equivalent potential temperature, and sea surface temperature (SST). Four predictors except for SST were obtained from differences of spatial-averaged value between May and January, and time average of Niño-3.4 index from February to April was used to consider the SST effects. As a result of prediction for the TC genesis from June to December during 1951 to 2007, years that the model forecasts are 21 years among the total 28 years when the observed TC genesis frequency was higher than normal year. The overall predictability was about 75%, and the model was also verified statistically through cross validation analysis using a method of the hindcast. Keywords: tropical cyclone genesis, logistic regression model, predictors, cross validation

This study investigates the use of selected ion flow tube mass spectrometry with an automated headspace pretreatment system for the continuous surveillance of water quality at wastewater treatment plants (WWTPs) and rivers. The reaction rates of the target compounds introduced using the headspace method were similar to those of the mass scan library, with a margin of error of

The aim of this study was to evaluate the wear properties of resin teeth with different opposing dental restorative materials. One type of resin tooth (Trubyte Biotone) was tested against six types of restorative materials including type III gold alloy (GO), monolithic zirconia (MZ), lithium disilicate glass ceramic (LD), nickel−chromium alloy (NC), feldspathic ceramic (FC), and steatite (ST). Two-body wear tests were performed under a vertical load of 5 kgf and thermo-cycling at 5/55 °C with a total of 120,000 cycles. The wear amount was quantified by measuring the volume loss of the resin teeth and the vertical substance loss of the opposing materials using three-dimensional images. The FC group showed a significantly greater amount of wear of the resin teeth, followed by the ST, NC, LD, MZ, and GO groups. The GO group showed significantly less wear of resin teeth than the other groups. There were no statistically significant differences in the wear of opposing restorative materials between groups. Within the limits of this study, it is recommended that zirconia, rather than feldspathic ceramic, should be used for restorations in the esthetic zone, and gold alloy should be used for areas with little or no esthetic demand.

This study aims to interpret and apply Asimov’s Three Laws of Robotics to home service robots. An agent is developed herein with the ability to focus its attention on human beings’ health, particularly the elderly and the diseased, by delivering food. The agent is developed on a cognitive agent architecture, state, operator, and result (Soar), to enable effective reasoning and decision-making skills. This study deals with basic home care services, such as food delivery and emergency response; therefore, common food care and emergency rules are newly proposed based on the priority values that correspond to a family’s circumstances and/or emergency levels. Asimov’s Three Laws are modified to aid the home service robot to follow a predetermined order in selecting a food item or recommending an alternative food item suitable for its user’s prevailing health condition. Experimental results confirm that reasoning and decision-making of the proposed agent are logically and ethically valid for a home service robot and ensure compliance with both the original and modified Asimov’s Three Laws.

There has been a growing interest in the relationship between sedative-hypnotics use and the risk of Alzheimer's dementia (AD) risk. This study aimed to evaluate the risk of AD associated with the use of sedative-hypnotics. A retrospective cohort study was conducted with randomly selected 5% samples from ≥50 years old beneficiaries of National Health Insurance Service (NHIS) of Korea from January 2002 to December 2015. The exposure to sedative-hypnotics was defined when prescribed over 30 defined daily dose (DDD) after January 2004 and it was categorized by prescribed dosage, types and half-lives of benzodiazepines. Time-dependent Cox regression model with a lag period of 5-years was used to evaluate the association between use of sedative-hypnotics and the risk of subsequent AD. Sensitivity analysis was performed for restricting sedative-hypnotics only when prescribed with insomnia. A total of 268,170 subjects were identified and subjects exposed to sedative-hypnotics showed a higher risk of AD (HR: 1.79; 95% CI: 1.72-1.86) than those who were not. There was an increased risk of AD among subjects exposed to benzodiazepines or zolpidem (HR: 1.75; 95% CI: 1.67-1.82) and antidepressants or low-dose antipsychotics (HR: 1.63; 95% CI: 1.42-1.87). The risk of AD was increased regardless of dose of sedative-hypnotics and half-life among benzodiazepines, especially in exposure to more than 360 DDD of sedative-hypnotics (HR: 1.78; 95% CI: 1.60-1.99) and the long-acting benzodiazepine (HR:1.77; 95% CI: 1.65-1.89).

Stellaria dichotoma var. lanceolata (SdLv), a member of the Caryophyllaceae, is a traditional herbal medicine that has been used to treat fever, night sweats, and malaria in East Asia. Inflammation plays an essential role in both host defense and pathogenesis during infection by diverse intracellular pathogens. Herein, we showed that an herbal extract from SdLv effectively attenuated inflammatory responses from infection of Mycobacterium abscessus (Mab), but not Toxoplasma gondii (T. gondii). In primary murine macrophages, Mab infection resulted in the rapid activation of nuclear factor (NF)-κB and mitogen-activated protein kinase (MAPK), as well as in the generation of proinflammatory cytokines, such as tumor necrosis factor α and interleukin-6, which were all significantly inhibited by pretreatment with SdLv. However, herbal extracts from Bupleurum chinense DC. (Buch) or Bupleurum falcatum L. (Bufa) did not affect M. abs-induced activation of proinflammatory responses. Importantly, we demonstrated that generation of intracellular reactive oxygen species, which are important signaling intermediaries in the activation of NF-κB and the MAPK signaling pathway, was rapidly increased in Mab-infected macrophages, and this was effectively suppressed by pretreatment with SdLv, but not Buch and Bufa. We further found that the treatment of Buch and Bufa, but not SdLv, led to the activation of NF-κB and the MAPK signaling pathway and the generation of intracellular reactive oxygen species. Moreover, oral administration of SdLv significantly reduced lethality in Mab-infected mice. Collectively, these results suggest the possible use of SdLv as an effective treatment for Mab infection.

This study compared shear bond strength (SBS) of six self-adhesive resin cements (SARC) and one resin-modified glass ionomer cement (RMGIC) to zirconia before and after thermocycling. The cylinder shape (Φ 2.35 mm × 3 mm) of six SARCs (G-CEM LinkAce (GLA), Maxcem Elite (MAX), Clearfil SA Luting (CSL), PermaCem 2.0 (PM2), Rely-X U200 (RXU), Smartcem 2 (SC2)) were bonded to the top surface of the zirconia specimens with light-curing. RMGIC (Fujicem (FJC)) was bonded to the specimens with self-curing. The shear bond strength of all cemented specimens was measured with universal testing machine. Half of the specimens were thermocycled 5000 times before shear bonding strength testing. Fractured surfaces were examined with a field-emission SEM (10,000×) and analyzed by energy dispersive x-ray analysis. MAX, PM2, SC2 group without thermocycling and GLA, MAX, PM2 group with thermocycling showed adhesive failure, but GLA, CSL, RXU, FJC group without thermocycling and SLC, RXU, SC2, FJC group with thermocycling indicated cohesive failure. Within the limitation of this study, All of SARCs except MAX demonstrated higher bond strength than that of RMGIC regardless of thermocycling. Also, SARC containing MDP monomers (CSL) retained better bonds than other cements.

ABSTRACT: By performing a statistical change-point analysis of activities of the tropical cyclones (TCs) that have affected Korea (K-TCs), it was found that there was a significant change between 1983 and 1984. During the period of 1984-2004 (P2), more TCs migrated toward the west, recurved in the southwest, and affected Korea, compared to the period of 1965-1983 (P1). These changes for P2 were related to the southwestward expansion of the subtropical western Pacific high (SWPH) and, simultaneously, elongation of its elliptical shape toward Korea. Because of these changes, the central pressure and lifetime of K-TC during P2 were deeper and longer, respectively, than figures for P1. This stronger K-TC intensity for P2 was related to the more southwestward genesis due to the southwestward expansion of the SWPH. The weaker vertical wind shear environment during P2 was more favorable for K-TC to maintain a strong intensity in the mid-latitudes of East Asia. Keywords: change-point analysis, tropical cyclone, subtropical western Pacific High, shift, vertical wind shear

ABSTRACT: In this study, the correlation between the frequency of summer tropical cyclones (TC) affecting areas around Korea over the last 37 years and the western North Pacific monsoon index (WNPMI) was analyzed. A clear positive correlation existed between the two variables, and this high positive correlation remained unchanged even when excluding El Niño-Southern Oscillation (ENSO) years. To investigate the causes of the positive correlation between these two variables, ENSO years were excluded, after which the 8 years with the highest WNPMI (strong WNPM phase) and the 8 years with the lowest WNPMI (weak WNPM phase) were selected, and the average difference between the two phases was analyzed.In the strong WNPM phase, TCs usually occurred in the eastern waters of the tropical and subtropical western North Pacific, and tended to pass the East China Sea on their way north toward Korea and Japan. In the weak WNPM phase, TCs usually occurred in the western waters of the tropical and subtropical western North Pacific, and tended to pass the South China Sea on their way west toward the southeastern Chinese coast and the Indochina peninsula. Therefore, TC intensity was higher in the strong WNPM phase, during which TCs are able to gain sufficient energy from the sea while moving a long distance to areas nearby Korea. TCs also tended to occur more often in the strong WNPM phase.In the difference between the two phases regarding 850 hPa and 500 hPa streamline, anomalous cyclones were reinforced in the tropical and subtropical western North Pacific, while anomalous anticyclones were reinforced in mid-latitude East Asian areas. Due to these two anomalous pressure systems, anomalous southeasterlies developed in areas near Korea, with these anomalous southeasterlies playing the role of anomalous steering flows making the TCs head toward areas near Korea. Also, due to the anomalous cyclones developed in the tropical and subtropical western North Pacific, more TCs could occur in the strong WNPM phase. Keywords: tropical cyclone, western North Pacific monsoon, El Niño-Southern Oscillation, Korea

The aim of this study was to evaluate the accuracy of dental models fabricated by conventional, milling, and three-dimensional (3D) printing methods. A reference model with inlay, single crown, and three-unit fixed dental prostheses (FDP) preparations was prepared. Conventional gypsum models (CON) were manufactured from the conventional method. Digital impressions were obtained by intraoral scanner, which were converted into physical models such as milled gypsum models (MIL), stereolithography (SLA), and digital light processing (DLP) 3D printed photopolymer models (S3P and D3P). Models were extracted as standard triangulated language (STL) data by reference scanner. All STL data were superimposed by 3D analysis software and quantitative and qualitative analysis was performed using root mean square (RMS) values and color difference map. Statistical analyses were performed using the Kruskal−Wallis test and Mann−Whitney U test with Bonferroni’s correction. For full arch, the RMS value of trueness and precision in CON was significantly smaller than in the other groups (p < 0.05/6 = 0.008), and there was no significant difference between S3P and D3P (p > 0.05/6 = 0.008). On the other hand, the RMS value of trueness in CON was significantly smaller than in the other groups for all prepared teeth (p < 0.05/6 = 0.008), and there was no significant difference between MIL and S3P (p > 0.05/6 = 0.008). In conclusion, conventional gypsum models showed better accuracy than digitally milled and 3D printed models.

Omega-3 polyunsaturated fatty acids (ω3-PUFAs) have potential protective activity in a variety of infectious diseases, but their actions and underlying mechanisms in Toxoplasma gondii infection remain poorly understood. Here, we report that docosahexaenoic acid (DHA) robustly induced autophagy in murine bone marrow-derived macrophages (BMDMs). Treatment of T. gondii-infected macrophages with DHA resulted in colocalization of Toxoplasma parasitophorous vacuoles with autophagosomes and reduced intracellular survival of T. gondii. The autophagic and anti-Toxoplasma effects induced by DHA were mediated by AMP-activated protein kinase (AMPK) signaling. Importantly, BMDMs isolated from Fat-1 transgenic mice, a well-known animal model capable of synthesizing ω3-PUFAs from ω6-PUFAs, showed increased activation of autophagy and AMPK, leading to reduced intracellular survival of T. gondii when compared with wild-type BMDMs. Moreover, Fat-1 transgenic mice exhibited lower cyst burden in the brain following infection with the avirulent strain ME49 than wild-type mice. Collectively, our results revealed mechanisms by which endogenous ω3-PUFAs and DHA control T. gondii infection and suggest that ω3-PUFAs might serve as therapeutic candidate to prevent toxoplasmosis and infection with other intracellular protozoan parasites.

This study demonstrates the utility of camphene as the pore-regulating agent for phase separation-based 3D plotting to produce hierarchical macro/micro-porous poly(ε-caprolactone) (PCL)−calcium phosphate (CaP) composite scaffolds, specifically featuring highly microporous surfaces. Unlike conventional particulate porogens, camphene is highly soluble in acetone, the solvent for PCL polymer, but insoluble in coagulation medium (water). In this study, this unique characteristic supported the creation of numerous micropores both within and at the surfaces of PCL and PCL−CaP composite filaments when using high camphene contents (40 and 50 wt%). In addition, the incorporation of the CaP particles into PCL solutions did not deteriorate the formation of microporous structures, and thus hierarchical macro/micro-porous PCL−CaP composite scaffolds could be successfully produced. As the CaP content increased, the in vitro biocompatibility, apatite-forming ability, and mechanical properties (tensile strength, tensile modulus, and compressive modulus) of the PCL−CaP composite scaffolds were substantially improved.

The aim of this study was to evaluate the wear properties of opposed dental ceramic restorative CAD/CAM materials and several posterior direct restorative composite resins. Three kinds of dental ceramics CAD/CAM materials (monolithic zirconia, lithium disilicate, leucite) and four dental composite resins—that is, MI Gracefil, Gradia Direct P, Estelite Σ Quick, and Filtek Supreme Ultra—were used in this study. For each of the 12 groups (three ceramics × four composite resins), five each of a canine-shaped ceramic specimen and a cuboidal shape opposing composite resin were prepared. All of the specimens were tested in a thermomechanical loading machine (50 N, 100,000 cycles, 5/55 °C). Wear losses of ceramic specimens and composite resin specimens were evaluated using a three-dimensional profiling system and an electronic scale, respectively. Statistical analyses were performed using the Kruskal−Wallis test and Mann−Whitney U test with Bonferroni’s correction. Zirconia showed significantly less volumetric loss than lithium disilicate or leucite regardless of composite resin type (p > 0.05/3 = 0.017), and that Estelite Σ Quick showed significantly more weight loss than Filtek Supreme Ultra, MI Gracefil, or Gradia Direct P regardless of ceramic type (p > 0.05/6 = 0.083). Zirconia showed less volumetric loss than lithium disilicate or leucite. Some composite resins opposing ceramics showed considerable weight loss.

During the process of plant growth, such as during the flowering stages and fruit development, the plants need to be provided with the various minerals and nutrients to grow. Nutrient deficiency is the cause of serious diseases in plant growth, affecting crop yield. In this article, we employed artificial neural network models to recognize, classify, and predict the nutritional deficiencies occurring in tomato plants (Solanum lycopersicum L.). To classify and predict the different macronutrient deficiencies in the cropping process, this paper handles the captured images of the macronutrient deficiency. This deficiency during the fruiting and leafing phases of tomato plant are based on a deep convolutional neural network (CNN). A total of 571 images were captured with tomato leaves and fruits containing the crop species at the growth stage. Among all images, 80% (461 captured images) were used for the training dataset and 20% (110 captured images) were applied for the validation dataset. In this study, we provide an analysis of two different model architectures based on convolutional neural network for classifying and predicting the nutrient deficiency symptoms. For instance, Inception-ResNet v2 and Autoencoder with the captured images of tomato plant growth under the greenhouse conditions. Moreover, a major type of statistical structure, namely Ensemble Averaging, was applied with two aforementioned predictive models to increase the accuracy of predictive validation. Three mineral nutrients, i.e., Calcium/Ca2+, Potassium/K+, and Nitrogen/N, are considered for use in evaluating the nutrient status in the development of tomato plant with these models. The aim of this study is to predict the nutrient deficiency accurately in order to increase crop production and prevent the emergence of tomato pathology caused by lack of nutrients. The predictive performance of the three models in this paper are validated, with the accuracy rates of 87.273% and 79.091% for Inception-ResNet v2 and Autoencoder, respectively, and with 91% validity using Ensemble Averaging.

The present study analyzed the interdecadal variation by applying the statistical change-point analysis to the frequency of the tropical cyclone (TC) that landed in the Korean Peninsula (KP) for the recent 54 years (1951 to 2004) and performed cluster classification of the Korea-landfall TC tracks using a Fuzzy Clustering Method (FCM). First, in the interdecadal variation analysis, frequency of TC that landed in the KP was largely categorized into three periods: high frequency period from 1951 to 1965, low frequency period from 1966 to 1985, and high frequency period from 1986 to 2004. The cluster analysis result of the Korea-landfall TC tracks produced the optimum number of clusters as four. In more detail, Cluster A refers to a pattern of landing in the southern coast in the KP starting from East China Sea followed by heading north while Cluster B refers to a pattern of landing in the west coast of the Korean Peninsula, also starting from East China Sea followed by heading north. Cluster C refers to a pattern of landing in the southern region of the west coast in the KP moving from mainland China while Cluster D refers to a pattern of landing in the mid-north region of the west coast in the Korean Peninsula, also moving from mainland China.

This study obtained the latitude where tropical cyclones (TCs) show maximum intensity and applied statistical change-point analysis on the time series data of the average annual values. The analysis results found that the latitude of the TC maximum intensity increased from 1999. To investigate the reason behind this phenomenon, the difference of the average latitude between 1999 and 2013 and the average between 1977 and 1998 was analyzed. In a difference of 500 hPa streamline between the two periods, anomalous anticyclonic circulations were strong in 30°–50°N, while anomalous monsoon trough was located in the north of South China Sea. This anomalous monsoon trough was extended eastward to 145°E. Middle-latitude region in East Asia is affected by the anomalous southeasterlies due to these anomalous anticyclonic circulations and anomalous monsoon trough. These anomalous southeasterlies play a role of anomalous steering flows that make the TCs heading toward region in East Asia middle latitude. As a result, TCs during 1999–2013 had higher latitude of the maximum intensity compared to the TCs during 1977–1998.

The aim of this in-vitro research was to evaluate the microtensile bond strength in the newly introduced PEKK tooth post with various surface treatments and resin cements. A fiberglass tooth post was included in order to compare it with PEKK as a possible post material. The microtensile bond strengths of the fiberglass post (FRC Postec Plus) and the PEKK post (Pekkton®) were tested using three kinds of self-adhesive resin cements (G-CEM LinkAce, Multilink Speed, and RelyX U200) and one self-etching resin cement (PANAVIA F2.0). The surface treatments of the fiberglass posts were processed according to the manufacturer’s recommendations (F1, application of 37% phosphoric acid etching gel and silanization). For the PEKK post groups, various surface treatments were performed like no surface treatment (P1), sandblasting (P2), silica-coating and silanization (P3), and sandblasting with a composite primer (P4). In the surface treatment, PEKK posts with silica coating and silane treatment (P3) showed a significantly higher microtensile bond strength (mean MPa: 18.09, p < 0.05). The highest microtensile bond strength was shown when the PEKK posts were treated with a silica coating and silane treatment and cemented with RelyX U200 (mean MPa: 22.22). The PEKK posts with surface treatments of silica-coating and silanization or sandblasting displayed superior microtensile bond strengths (mean MPa: 18.09 and 16.25, respectively) compared to the conventional fiberglass posts (mean MPa: 14.93, p < 0.05).

The aim of this study was to introduce the newly developed micro-locking implant prosthetic system and to evaluate the resulting its characteristics. To evaluate load-bearing capacity, 25 implants were divided into five groups: external-hexagon connection (EH), internal-octagon connection (IO), internal-hexagon connection (IH), one-body implant (OB), micro-locking implant system (ML). The maximum compressive load was measured using a universal testing machine (UTM) according to the ISO 14801. Retention was evaluated in two experiments: (1) a tensile test of the structure modifications of the components (attachment and implant) and (2) a tensile test after cyclic loading (total 5,000,000 cycles, 100 N, 2 Hz). The load-bearing capacity of the ML group was not significantly different from the other groups (p > 0.05). The number of balls in the attachment and the presence of a hexagonal receptacle did not show a significant correlation with retention (p > 0.05), but the shape of the retentive groove in the implant post had a statistically significant effect on retention (p < 0.05). On the other hand, the retention loss was observed during the initial 1,000,000 cycles, but an overall constant retention was maintained afterward. Various preclinical studies on this novel micro-locking implant prosthetic system should continue so that it can be applied in clinical practice.

In this study, a new concept of a 3D-printed scaffold was introduced for the accurate placement of an implant and the application of a recombinant human bone morphogenetic protein-2 (rhBMP-2)-loaded bone graft. This preliminary study was conducted using two adult beagles to evaluate the 3D-printed polycaprolactone (PCL)/β-tricalcium phosphate (β-TCP)/bone decellularized extracellular matrix (bdECM) scaffold conjugated with rhBMP-2 for the simultaneous use as an implant surgical guide stent and bone graft material that promotes new bone growth. Teeth were extracted from the mandible of the beagle model and scanned by computed tomography (CT) to fabricate a customized scaffold that would fit the bone defect. After positioning the implant guide scaffold, the implant was placed and rhBMP-2 was injected into the scaffold of the experimental group. The two beagles were sacrificed after three months. The specimen block was obtained and scanned by micro-CT. Histological analysis showed that the control and experimental groups had similar new bone volume (NBV, %) but the experimental group with BMP exhibited a significantly higher bone-to-implant contact ratio (BIC, %). Within the limitations of this preliminary study, a 3D-printed scaffold conjugated with rhBMP-2 can be used simultaneously as an implant surgical guide and a bone graft in a large bone defect site. Further large-scale studies will be needed to confirm these results.

The aim of the study was to evaluate the effects of polymeric computer-aided design/computer-aided manufacturing CAD/CAM materials on antagonistic primary tooth wear. Five CAD/CAM polymeric materials were examined: Vipi Block Monocolor (VBM), Yamahachi polymethylmethacrylate (PMMA) (YAP), Mazic Duro (MZD), Vita Enamic (ENA), and Pekkton (PEK). All of the specimens were tested in a thermomechanical loading machine with the primary canine as the antagonist (50 N, 1.2 × 105 cycles, 1.7 Hz, 5/55 °C). The wear losses of the antagonist tooth and the restorative materials were calculated using reverse modelling software and an electronic scale. VBM and ENA showed significantly higher antagonist tooth wear than PEK (p < 0.05), but there was no significant difference observed among VBM, YAP, MZD, and ENA (p > 0.05). PEK showed the largest value in both material volumetric and weight losses. In terms of material volumetric losses, there was no significant difference between all of the groups (p > 0.05). In terms of material weight losses, PEK was significantly larger than ENA (p < 0.05), but there was no significant difference between VBM, YAP, MZD, and ENA (p > 0.05). Volumetric and weight losses of materials showed similar wear behaviour. However, the wear patterns of antagonists and materials were different, especially in PEK.

This study demonstrates the utility of the newly developed self-assembly-induced gelation technique for the synthesis of porous collagen/hydroxyapatite (HA) composite microspheres with a nanofibrous structure. This new approach can produce microspheres of a uniform size using the droplets that form at the nozzle tip before gelation. These microspheres can have a highly nanofibrous structure due to the immersion of the droplets in a coagulation bath (water/acetone), in which the collagen aggregates in the solution can self-assemble into fibrils due to pH-dependent precipitation. Bioactive HA particles were incorporated into the collagen solutions, in order to enhance the bioactivity of the composite microspheres. The composite microspheres exhibited a well-defined spherical morphology and a uniform size for all levels of HA content (0 wt %, 10 wt %, 15 wt %, and 20 wt %). Collagen nanofibers—several tens of nanometers in size—were uniformly present throughout the microspheres and the HA particles were also well dispersed. The in vitro apatite-forming ability, assessed using the simulated body fluid (SBF) solution, increased significantly with the incorporation of HA into the composite microspheres.

This study identified the causes of the nonoccurrence of tropical cyclones (TCs) in August 2014 by examining large-scale environments. First, over the previous 30 years, the TC genesis frequency in August showed an overall statistically significant decline. In the tropical and subtropical western Pacific, the outgoing longwave radiation anomaly index also exhibited an overall increase until recently. Regarding precipitable water and precipitation, an analysis was performed on the difference between the mean values for August 2014 and the mean values for August over the previous 30 years. As a result, while convective activities were suppressed in the tropical and subtropical western Pacific, convective activities were strong in the mid-latitudes of East Asia. This indicates that while the western North Pacific summer monsoon was weakened in August 2014, the East Asian summer monsoon was strengthened. The weakening of the western North Pacific summer monsoon may have made it difficult for TCs to occur. An analysis of 850 hPa and 500 hPa stream flows showed the strengthening of anomalous huge anticyclonic circulations in the tropical and subtropical western Pacific, whereas anomalously cyclonic circulations were reinforced in the mid-latitudes of East Asia. This was associated with the result that the western North Pacific subtropical high (WNPSH) showed further westward and southward expansion in August 2014 compared to the climatological mean WNPSH. Therefore, TCs were unlikely to occur in the tropical and subtropical western Pacific, but anomalous cold northerlies and anomalous warm southerlies converged in the Japanese Islands after originating in China’s central region and passing the East China Sea. Therefore, a favorable environment for the occurrence of precipitation had been formed.