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Taurine plays important roles in the metabolism of bile acid, cholesterol and lipid. However, little relevant information has been available in fish where taurine has been identified as a conditionally essential nutrient. The present study aimed to investigate the effects of dietary taurine on the metabolism of bile acid, cholesterol, and lipid in tiger puffer, which is both an important aquaculture species and a good research model having a unique lipid storage pattern. An 8-week feeding trial was conducted in a flow-through seawater system. Three experimental diets differed only in taurine level, i.e., 1.7, 8.2, and 14.0 mg kg-1. Taurine supplementation increased the total bile acid content in liver, but decreased the content in serum. Taurine supplementation also increased the contents of total cholesterol (TC) and HDL-C in both liver and serum. The hepatic bile acid profile mainly includes taurocholic acid (94.48%), taurochenodeoxycholic acid (4.17%), and taurodeoxycholic acid (1.35%), and the contents of all these conjugated bile acids were increased by dietary taurine. The hepatic lipidomics analysis showed that taurine tended to decrease the abundance of individual phospholipids, and increase those of some individual triglycerides and ceramides. The hepatic mRNA expression study showed that taurine stimulated the biosynthesis of both bile acid and cholesterol, possibly via regulation of FXR and HDL metabolism. Taurine also stimulated the hepatic expression of lipogenic genes. In conclusion, dietary taurine stimulated the hepatic biosynthesis of both bile acid and cholesterol, and tended to regulate the lipid metabolism in multiple ways.
The aerodynamic characteristics of a hovering rhinoceros beetle are numerically and theoretically investigated. Its wing kinematics is measured using high speed cameras and used for numerical simulations of flow around a flapping rhinoceros beetle in hovering flight. The numerical results show that the aerodynamic forces generated (especially for lift) and power required by the hind wing during a quasi-periodic state are quite different from those during the first stroke. This indicates that the wing–wake interaction significantly affects the aerodynamic performance of the hind wing during the quasi-periodic state. Also, twisting of the hind wing along the wing span direction does not contribute much to total force generation as compared to that of the flat wing, and the role of elytron and body on the aerodynamic performance is quite small, at least for the present hovering flight. Based on a previous model (Wang et al., J. Fluid Mech., vol. 800, 2016, pp. 688–719), we suggest an improved predictive aerodynamic model without any ad hoc model constants for a rigid and flat hind wing by considering the effect of the wing–wake interaction in hovering flight. In this model, we treat the wake as a steady or unsteady non-uniform downwash motion and obtain its magnitude by combining a quasi-steady blade element theory with an inviscid momentum theory. The lift and drag forces and aerodynamic power consumption predicted by this model are in excellent agreement with those obtained from numerical simulations.
Seoul is the third most densely populated area in the world except for the city-state. However, a national disaster plan has not yet been established.
From September 2017, representatives of seven regional emergency medical centers in Seoul met monthly and decided to investigate basic data for the future establishment of surge capacity planning.
Staff, supply, space, and systems for surge capacity were surveyed in seven hospitals. The additional surveyed data were as follows: hospital incident command system and actual operational experience; performance of disaster drill; safety and security plan; estimation of surge capacity in normal operating conditions and extreme operating conditions; alternative therapeutic spaces; back-up plan to call non-duty medical staff; decontamination equipment; contingency plan for stuff shortage; etc.
All the hospitals reported they have hospital incident command systems and held disaster drills every year, however, the two hospitals (28.5%) had no real experience of hospital incident command system activation. Five hospitals (71.4%) did not have a safety and security plan. They replied they can treat average 7.7 emergency patients (Korean Triage and Acute scale (KTAS) ≤ 3), 10 non-emergent patients (KTAS>4), 0.9 surgical patients and 0.7 unstable patients simultaneously in normal operating conditions. In extreme operating conditions, they replied they can treat average 26.4 emergency patients (KTAS ≤ 3), 54.3 non-emergent patients (KTAS>4), 37 surgical patients and 2.3 unstable patients simultaneously. The two hospitals (28.5%) had no alternative therapeutic spaces, no back-up plan to call non-duty medical staff and no contingency plan for stuff shortage. Three hospitals (42.9%) did not have decontamination equipment.
The survey revealed the basic data for surge capacity planning in Seoul. Data from hospitals other than regional emergency medical centers should be collected for the completion of disaster plans.
Traumatic brain injury (TBI) is an important public health concern because of the high mortality rate of young people and a high proportion among the trauma. According to studies, patients visiting the emergency department (ED) with TBI comprise 1.4% of all ED patients.
The authors think that the characteristics of patients with TBI will vary according to the age group. Therefore, the purpose of this study is to investigate the clinical and social characteristics of patients with TBI visiting the ED by age group.
Trauma patients who conducted brain CT at the ED of Korean University Hospital (three hospitals) for 3 years from March 2013 to February 2016 were enrolled. Medical records were investigated retrospectively. The GCS scores were estimated at initial ED arrival. The primary outcome was to determine the characteristics of each age groups with gender, severity (by GSC score), trauma mechanism, and admission rate.
A total of 15,567 TBI patients received brain CT evaluation during the investigation period. Based on age, patients in their 50s were the most common (16.5%). Regarding the severity, the ratio of mild was higher in under patients under 9 (99.3%); the ratio of severe was higher for patients in their 20s (4.6%). In almost every age group, the male ratio of TBI was higher, except for females aged 70 or older. Under 19 years of age, the ambulance utilization rate was lower than any other age group. The most common injury mechanism was a collision, the next was a traffic accident, and in under 9, a fall was the most common. 70.1% of patients returned home after treatments.
Identifying the characteristics of patients with TBI visiting ED is fundamental. Therefore, it is necessary to continuously collect basic data on TBI among patients visiting the ED.
In this study, we have examined ceramic matrix composites with silicon carbide fibers in a melt-infiltrated silicon carbide matrix (SiC/SiC). We subjected samples to tensile loads while collecting micro X-ray computed tomography images. The results showed the expected crack slowing mechanisms and lower resistance to crack propagation where the fibers ran parallel and perpendicular to the applied load respectively. Cracking was shown to initiate not only from the surface but also from silicon inclusions. Post heat-treated samples showed longer fiber pull-out than the pristine samples, which was incompatible with previously proposed mechanisms. Evidence for oxidation was identified and new mechanisms based on oxidation or an oxidation assisted boron nitride phase transformation was therefore proposed to explain the long pull-out. The role of oxidation emphasizes the necessity of applying oxidation resistant coatings on SiC/SiC.
Despite the possibility that cognitive deficits associated with depression may have different patterns depending on the level of neurocognitive impairment, there remains no clear evidence of this. This study aimed to investigate the differential association between depression and cognitive function in patients with mild cognitive impairment (MCI) and Alzheimer’s disease (AD).
A cross-sectional analysis was performed of data from 1,724 patients with MCI and 1,247 patients with AD from the Clinical Research Center for Dementia in Korea. Depression was assessed using the Korean form of the Geriatric Depression Scale, and cognition was measured using the Seoul Neuropsychological Screening Battery, which includes five domains (attention, language and related function, visuospatial function, memory, and frontal/executive function).
Significant differences were found between the two groups (non-depressed vs. depressed) in visuospatial, memory, and executive function domains in the MCI group, as well as in the attention domain in the AD group. The association between depressive symptoms and cognitive function was significantly greater in patients with MCI than in those with AD. These associations were more pronounced in memory and executive function.
Our findings suggest that the association between depression and decreased cognitive function is more pronounced in MCI than AD.
We introduce a second numerical index for real Banach spaces with non-trivial Lie algebra, as the best constant of equivalence between the numerical radius and the quotient of the operator norm modulo the Lie algebra. We present a number of examples and results concerning absolute sums, duality, vector-valued function spaces…which show that, in many cases, the behaviour of this second numerical index differs from the one of the classical numerical index. As main results, we prove that Hilbert spaces have second numerical index one and that they are the only spaces with this property among the class of Banach spaces with one-unconditional basis and non-trivial Lie algebra. Besides, an application to the Bishop-Phelps-Bollobás property for the numerical radius is given.
The status of Asian populations of the Eurasian otter Lutra lutra is largely unknown. Since its designation as a Natural Monument (in 1983) and as Endangered (in 1997) in South Korea the authorities there have been trying to conserve and recover the species. We conducted a national otter survey by standard methods in 2017 and compared the current otter distribution to those recorded in a previous survey (2010). We found otter signs in 84.5% of 1,105 10 × 10 km grid cells, with the highest sprainting intensity in the south-west in the Yeongsan River Basin and on the south coast, where we recorded 7.05 and 6.26 spraints/site, respectively. Despite relatively low spraint densities, the otter has expanded its range since 2010 by colonizing urban areas. This trend suggests that South Korea could be a source area for the recovery of the Eurasian otter in East Asia.
Firefighters are routinely exposed to various traumatic events and often experience a range of trauma-related symptoms. Although these repeated traumatic exposures rarely progress to the development of post-traumatic stress disorder, firefighters are still considered to be a vulnerable population with regard to trauma.
To investigate how the human brain responds to or compensates for the repeated experience of traumatic stress.
We included 98 healthy firefighters with repeated traumatic experiences but without any diagnosis of mental illness and 98 non-firefighter healthy individuals without any history of trauma. Functional connectivity within the fear circuitry, which consists of the dorsal anterior cingulate cortex, insula, amygdala, hippocampus and ventromedial prefrontal cortex (vmPFC), was examined using resting-state functional magnetic resonance imaging. Trauma-related symptoms were evaluated using the Impact of Event Scale – Revised.
The firefighter group had greater functional connectivity between the insula and several regions of the fear circuitry including the bilateral amygdalae, bilateral hippocampi and vmPFC as compared with healthy individuals. In the firefighter group, stronger insula–amygdala connectivity was associated with greater severity of trauma-related symptoms (β = 0.36, P = 0.005), whereas higher insula–vmPFC connectivity was related to milder symptoms in response to repeated trauma (β = −0.28, P = 0.01).
The current findings suggest an active involvement of insular functional connectivity in response to repeated traumatic stress. Functional connectivity of the insula in relation to the amygdala and vmPFC may be potential pathways that underlie the risk for and resilience to repeated traumatic stress, respectively.
We study approximation of operators between Banach spaces
that nearly attain their norms in a given point by operators that attain their norms at the same point. When such approximations exist, we say that the pair
has the pointwise Bishop–Phelps–Bollobás property (pointwise BPB property for short). In this paper we mostly concentrate on those
, called universal pointwise BPB domain spaces, such that
possesses pointwise BPB property for every
, and on those
, called universal pointwise BPB range spaces, such that
enjoys pointwise BPB property for every uniformly smooth
. We show that every universal pointwise BPB domain space is uniformly convex and that
spaces fail to have this property when
. No universal pointwise BPB range space can be simultaneously uniformly convex and uniformly smooth unless its dimension is one. We also discuss a version of the pointwise BPB property for compact operators.
In 2005, using a famous lemma of Atkin and Swinnerton-Dyer (Some properties of partitions, Proc. Lond. Math. Soc. (3) 4 (1954), 84–106), Yesilyurt (Four identities related to third order mock theta functions in Ramanujan’s lost notebook, Adv. Math. 190 (2005), 278–299) proved four identities for third order mock theta functions found on pages 2 and 17 in Ramanujan’s lost notebook. The primary purpose of this paper is to offer new proofs in the spirit of what Ramanujan might have given in the hope that a better understanding of the identities might be gained. Third order mock theta functions are intimately connected with ranks of partitions. We prove new dissections for two rank generating functions, which are keys to our proof of the fourth, and the most difficult, of Ramanujan’s identities. In the last section of this paper, we establish new relations for ranks arising from our dissections of rank generating functions.
Objectives: The aim of this study was to investigate alterations in functional connectivity, white matter integrity, and cognitive abilities due to sports-related concussion (SRC) in adolescents using a prospective longitudinal design. Methods: We assessed male high school football players (ages 14–18) with (n=16) and without (n=12) SRC using complementary resting state functional MRI (rs-fMRI) and diffusion tensor imaging (DTI) along with cognitive performance using the Immediate Post-Concussive Assessment and Cognitive Testing (ImPACT). We assessed both changes at the acute phase (<7 days post-SRC) and at 21 days later, as well as, differences between athletes with SRC and age- and team-matched control athletes. Results: The results revealed rs-fMRI hyperconnectivity within posterior brain regions (e.g., precuneus and cerebellum), and hypoconnectivity in more anterior areas (e.g., inferior and middle frontal gyri) when comparing SRC group to control group acutely. Performance on the ImPACT (visual/verbal memory composites) was correlated with resting state network connectivity at both time points. DTI results revealed altered diffusion in the SRC group along a segment of the corticospinal tract and the superior longitudinal fasciculus in the acute phase of SRC. No differences between the SRC group and control group were seen at follow-up imaging. Conclusions: Acute effects of SRC are associated with both hyperconnectivity and hypoconnectivity, with disruption of white matter integrity. In addition, acute memory performance was most sensitive to these changes. After 21 days, adolescents with SRC returned to baseline performance, although chronic hyperconnectivity of these regions could place these adolescents at greater risk for secondary neuropathological changes, necessitating future follow-up. (JINS, 2018, 24, 781–792)
To verify the validity of a semiautomated surgical site infection (SSI) surveillance system using electronic screening algorithms in 38 categories of surgery.
A cohort study for validation of semiautomated SSI surveillance system using screening algorithms.
A 1,989-bed tertiary-care referral center in Seoul, Republic of Korea.
A dataset of 40,516 surgical procedures in 38 categories stored in the conventional SSI surveillance registry at the Samsung Medical Center between January 2013 and December 2014 was used as the reference standard. In the semiautomated surveillance system, electronic screening algorithms flagged cases meeting at least 1 of 3 criteria: antibiotic prescription, microbial culture, and infectious disease consultation. Flagged cases were audited by infection preventionists. Analyses of sensitivity, specificity, and positive predictive value (PPV) were conducted for the semiautomated surveillance system, and its effect on reducing the workload for chart review was evaluated.
A total of 575 SSI events (1·42%) were identified by conventional SSI surveillance. The sensitivity of the semiautomated SSI surveillance was 96·7%, and the PPV of the screening algorithms alone was 4·1%. Semiautomated SSI surveillance reduced the chart review workload of the infection preventionists from 1,283 to 482 person hours per year (a 62·4% decrease).
Compared to conventional surveillance, semiautomated surveillance using electronic screening algorithms followed by chart review of selected cases can provide high-validity surveillance results and can significantly reduce the workload of infection preventionists.
Biogenesis can be understood as the final process of the Universe's evolution, from Planck scale down to nuclear scale to atomic scale to molecular scale, then finally to bioscale, with the breaking of relevant symmetries at every step. By assuming the simplest definition of life, that life is just a molecular system which can reproduce itself (auto-reproducing molecular system – ARMS) and has such kinetic ability (kineto-molecular system), at least for its microscopic level, as to respond actively to its surrounding environments, we tried to explain the origin of life, taking the final step of the Universe evolution. We found a few clues for the origin of life, such as: (1) As the Universe expands and gets extremely cold, biogenesis can take place by ARMS, new level of stabilization may be achievable only at ‘locally cold places’ (LCPs), such as comets. (2) There must be the parity breaking in the bioscale stabilization process, which can be violated spontaneously, or dynamically by the van der Waals forces possible only at LCPs. (3) The rule of bioparity breaking is universal within the biohorizon. So we will find, e.g. only left-handed amino acids in all living beings dwelling within our Galaxy. (4) The idea of biogenesis through the bioscale stabilization in the evolution of the Universe looks very consistent with Panspermia hypothesis and supports it by providing a viable answer for life's origin at such LCPs.
Due to the lack of an effective prophylactic intervention and diagnosis, human liver fluke Clonorchis sinensis continues to afflict a large human population, causing a chronic inflammatory bile duct disease. With an aim to identify target antigens for sensitive serodiagnosis, adenylate kinase 3 of C. sinensis (CsAK3) was successfully expressed in soluble form in Escherichia coli by fusion to an RNA-interacting domain derived from human Lys-tRNA synthetase and purified by Ni2+-affinity chromatography. Anti-CsAK3 serum was raised by immunization of mice, and Western blotting confirmed that CsAK3 was expressed in adult-stage C. sinensis. Histochemical analysis showed that CsAK3 was localized to the subtegumental tissue of C. sinensis and was excreted into the bile duct of the host. When tested against sera from various parasite-infected patients by enzyme-linked immunosorbent assay, the recombinant CsAK3 elicited a specific response to C. sinensis-infected sera. The results suggest that CsAK3, either alone or in combination with other antigens, could be used for improving the clinical diagnosis of clonorchiasis.
Spirituality is what gives people meaning and purpose in life, and it has been recognized as a critical factor in patients’ well-being, particularly at the ends of their lives. Studies have demonstrated relationships between spirituality and patient-reported outcomes such as quality of life and mental health. Although a number of studies have suggested that spiritual belief can be associated with mortality, the results are inconsistent. We aimed to determine whether spirituality was related to survival in advanced cancer inpatients in Korea.
For this multicenter study, we recruited adult advanced cancer inpatients who had been admitted to seven palliative care units with estimated survival of <3 months. We measured spirituality at admission using the Korean version of the Functional Assessment of Chronic Illness Therapy-Spiritual Well-Being (FACIT-sp), which comprises two subscales: meaning/peace and faith. We calculated a Kaplan-Meier curve for spirituality, dichotomized at the predefined cutoffs and medians for the total scale and each of the two subscales, and performed univariate regression with a Cox proportional hazard model.
We enrolled a total of 204 adults (mean age: 64.5 ± 13.0; 48.5% female) in the study. The most common primary cancer diagnoses were lung (21.6%), colorectal (18.6%), and liver/biliary tract (13.0%). Median survival was 19.5 days (95% confidence interval [CI95%]: 23.5, 30.6). Total FACIT-sp score was not related to survival time (hazard ratio [HR] = 0.981, CI95% = 0.957, 1.007), and neither were the scores for its two subscales, meaning/peace (HR = 0.969, CI95% = 0.932, 1.008) and faith (HR = 0.981, CI95% = 0.938, 1.026).
Significance of results
Spirituality was not related to survival in advanced cancer inpatients in Korea. Plausible mechanisms merit further investigation.