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This work reports a series of new organic electro‐optic salt crystals possessing unusual orthogonal dipole‐coupling assembly that act as dimple‐free THz generators. In the new crystals, optically anisotropic aromatic anions introducing highly electronegative fluorinated substituents are orthogonally assembled with optically anisotropic nonlinear optical benzothiazolium cations. These orthogonal cation–anion assembled crystals exhibit strong suppression of intrinsic THz phonon modes along the polar axis, which results in a wide THz absorption‐free range from 1.5 to 4.0 THz without substantial absorption peaks. This is sharply in contrast to previous benchmark crystals with parallel cation–anion assembly; for example, in analogous crystals, several strong absorption peaks appear in this frequency range. This absence of strong absorption peaks is attributed to the orthogonal cation–anion dipole coupling assembly, the formation of fluorinate‐induced strong interionic interactions, and a high packing ability of uniaxial anions. With top‐level macroscopic optical nonlinearity, new orthogonal‐dipole assembled crystals make dimple‐free THz wave generation possible in the range of about 1.5–4.0 THz, which is very beneficial for characterizing signature peaks related to molecular phonon motions of analytes in THz spectroscopy. Therefore, orthogonal molecular assembly of optically highly anisotropic molecules provides an efficient way to substantially reduce and control intrinsic THz phonon modes. [ABSTRACT FROM AUTHOR]

Periventricular nodular heterotopia (PNH) is a neuronal migration disorder that occurs during early brain development. Patients with PNH may be asymptomatic and have normal intelligence; however, PNH is also known to cause various symptoms such as seizures, dyslexia, and cardiovascular anomalies. PNH is not commonly diagnosed during early infancy because of the lack of clinical manifestations during this period. We present the case of a female infant diagnosed with PNH based on brain magnetic resonance imaging, who had symptomatic patent ductus arteriosus that had to be ligated surgically and had prolonged feeding cyanosis with frequent apneic spells. [ABSTRACT FROM AUTHOR]

Solid‐state molecular phonons play a crucial role in the performance of diverse photonic and optoelectronic devices. In this work, new organic terahertz (THz) generators based on a catechol group that acts as a phonon suppressing intermolecular adhesive are developed. The catechol group is widely used in mussel‐inspired mechanical adhesive chemistry. Newly designed organic electro‐optic crystals consist of catechol‐based nonlinear optical 4‐(3,4‐dihydroxystyryl)‐1‐methylpyridinium (DHP) cations and 4‐(trifluoromethyl)benzenesulfonate anions (TFS), which both have multiple interionic interaction capability. Interestingly, compared to benchmark organic crystals for THz generators, DHP‐TFS crystals concomitantly achieve top level values of the lowest void volume and the highest crystal density, resulting in an exceptionally small amplitude of solid‐state molecular phonons. Simultaneously achieving small molecular phonon amplitude, large optical nonlinearity and good phase matching at infrared optical pump wavelengths, DHP‐TFS crystals are capable of generating broadband THz waves of up to 16 THz with high optical‐to‐THz conversion efficiency; one order of magnitude higher than commercial inorganic THz generators. [ABSTRACT FROM AUTHOR]

Purpose: To build an age prediction model, we measured CD4+ and CD8+ cells, and humoral components in canine peripheral blood. Materials and Methods: Large Belgian Malinois (BGM) and German Shepherd Dog (GSD) breeds (n=27), aged from 1 to 12 years, were used for this study. Peripheral bloods were obtained by venepuncture, then plasma and peripheral blood mononuclear cells (PBMCs) were separated immediately. Six myokines, including interleukin (IL)-6, IL-8, IL-15, leukemia inhibitory factor (LIF), growth differentiation factor 8 (GDF8), and GDF11 were measured from plasma and CD4+/CD8+ T-lymphocytes ratio were measured from PBMC. These parameters were then tested with age prediction models to find the best fit model. Results: we found that the T-lymphocyte ratio (CD4+/CD8+) was significantly correlated with age (r=0.46, p=0.016). Among the six myokines, only GDF8 showed a significant correlation with age (r=0.52, p=0.005). Interestingly, these two markers showed better correlations in male dogs than females, and BGM breed than GSD. Using these two age biomarkers, we could obtain the best fit in a quadratic linear mixed model (r=0.77, p=3×10-6). Conclusions: Age prediction is a challenging task because of complication with biological age. Our quadratic linear mixed model using CD4+/CD8+ ratio and GDF8 level showed a meaningful age prediction. [ABSTRACT FROM AUTHOR]

Newly designed halogenated organic quinolinium crystals proposed in this work provide fully optimized molecular ordering for maximizing the optical nonlinearity and high‐performance broadband terahertz (THz) wave generation. The ultralarge diagonal optical nonlinearity (almost 300 × 10−30 esu) of the new halogenated crystals is approximately two times larger than that of state‐of‐the‐art pyridinium‐based crystals. In contrast, nonhalogenated analogous crystals exhibit very low (or vanishing) diagonal optical nonlinearity. This is attributed to halogen‐induced unique interionic interactions and fine‐tuning of the space‐filling characteristics. In addition, the halogenated crystals show a good ability for bulk crystal growth of few millimeters lateral size with plate‐like morphology and high thermal stability that are finally required for real‐world applications. The new halogenated quinolinium crystals exhibit excellent THz wave generation characteristics, significantly surpassing the limit of conversion efficiency and spectral bandwidth of inorganic benchmark crystals. A 0.16 mm thick chlorinated crystal generates a 29‐times larger THz field than 1.0 mm thick inorganic ZnTe crystals at 1500 nm pump wavelength with a flat and broadband spectrum extending up to ≈8 THz. Therefore, introducing halogen substituents is a potential design strategy for designing new organic crystals showing ultralarge macroscopic hyperpolarizability and high‐performance THz wave generation. [ABSTRACT FROM AUTHOR]

Ultra‐broadband THz photonics covering the 0.3–20 THz range provides a very attractive foundation for a wide range of basic research and industrial applications. However, the lack of ultra‐broadband THz devices has yet to be overcome. In this work, high‐density organic electro‐optic crystals are newly developed for efficient THz wave generation in a very broad THz spectral range and are successfully used for a broadband THz time‐domain spectroscopy. The new organic THz generator crystals, namely the OHP‐TFS crystals, have very low void volume, high density, and are shown to cover the ultra‐broadband THz spectrum up to about 15 THz, which cannot be easily accessed with the more widely used inorganic‐based THz generators. In addition to the very favorable broadband properties, the generated THz electric‐field amplitude at the pump wavelength of 1560 nm is about 40 times higher than that generated by a commercial inorganic THz generator (ZnTe crystal). By using the newly developed OHP‐TFS as generation crystal in a compact table‐top all‐organic THz time‐domain spectrometer based on a low‐cost telecom fiber laser, the optical characteristics of a model material are successfully determined in the broad 1.5–12.5 THz range with high accuracy. [ABSTRACT FROM AUTHOR]

A 53-year-old woman presented with dyspnea. She had undergone extended thymectomy for an invasive thymoma two months prior. CT revealed numerous small nodules in the lung. After that, she deteriorated owing to acute respiratory distress syndrome (ARDS), and the vascular surgeon planned veno-venous extracorporeal membrane oxygenation (ECMO). During percutaneous cannulation through the left femoral vein, a vascular injury was suspected, and the patient's vital signs became unstable. Diagnostic angiography showed a ruptured left common iliac vein, and the bleeding was stopped by placement of a stent-graft. May-Thurner syndrome was diagnosed on abdominal CT. Here, we report a rare case of ECMO-related vascular injury in a patient with an unrecognized anatomical variant, May-Thurner syndrome. [ABSTRACT FROM AUTHOR]

This is a rare case of a 73-year-old male patient who presented with hematochezia and was treated using transcatheter arterial embolization following upper gastrointestinal bleeding in the third portion of the duodenum. The cause of the bleeding was not found on gastrointestinal endoscopy and CT. On the third day of hospitalization, the hemoglobin level continued to decrease. A technetium-99m-labeled red blood cell scan revealed suspicious bleeding in the diverticulum of the third portion of the duodenum. Superior mesenteric artery angiography showed active bleeding from the posteroinferior pancreaticoduodenal artery, which was embolized with N-butyl cyanoacrylate. The patient was discharged on the seventh day after embolization without re-bleeding or complication. We report a rare case of a patient with active bleeding from a duodenal diverticulum that was difficult to diagnose using routine modalities. Herein, we report a rare case of a patient with active bleeding from a duodenal diverticulum that was difficult to diagnose using routine modalities. We also conducted a relavant literature review. [ABSTRACT FROM AUTHOR]

OBJECTIVES: The adenoid pad, which is located between the orifice of the Eustachian tube (ET) and posterior nasal cavity, can affect the development of otitis media with effusion (OME) because of its anatomical location. The aim of the present study was to evaluate adenoid microbial colonization through 16S ribosomal RNA (rRNA) pyrosequencing, an advanced molecular technique, and to document the relationship with OME. MATERIALS and METHODS: Adenoid samples were collected using sterile cotton from 32 children during ventilation tube insertion. Sixteen children with OME who underwent tonsillectomy and adenoidectomy due to obstructive symptoms were assigned to the OME group and sixteen children without OME were assigned to the control group. We performed a 16S rRNA-based culture-independent survey of bacterial communities using the MiSeq platform. RESULTS: The diversity index, mean operational taxonomic units, and Shannon index were lower in the OME group than those in the control group. A taxonomic analysis showed differences in microbiota distribution between the OME and control groups at the phylum, genus, and species levels. The analysis, which was based on weighted UniFrac distances, revealed differences in microbial composition between the two groups. CONCLUSION: Bacterial community analysis using 16S rRNA pyrosequencing allows us to understand the relationship between the microbial communities of adenoids and the development of OME better. [ABSTRACT FROM AUTHOR]

Rapamycin (RM), a drug that inhibits the mechanistic target of rapamycin (mTOR) pathway and responds to nutrient availability, seemingly mimics the effects of caloric restriction (CR) on healthy life span. However, the extent of the mechanistic overlap between RM and CR remains incompletely understood. Here, we compared the impact of CR and RM on cellular metabolic status. Both regimens maintained intracellular ATP through the chronological aging process and showed enhanced mitochondrial capacity. Comparative transcriptome analysis showed that CR had a stronger impact on global gene expression than RM. We observed a like impact on the metabolome and identified distinct metabolites affected by CR and RM. CR severely reduced the level of energy storage molecules including glycogen and lipid droplets, whereas RM did not. RM boosted the production of enzymes responsible for the breakdown of glycogen and lipid droplets. Collectively, these results provide insights into the distinct energy metabolism mechanisms induced by CR and RM, suggesting that these two anti-aging regimens might extend life span through distinctive pathways. [ABSTRACT FROM AUTHOR]

This paper proposes a compensation method to improve the distorted space vectors when a 3-level Neutral Point Clamped (NPC) inverter has an unbalanced neutral point voltage. Since both the neutral point voltage of the DC link and the space vector of a 3-level NPC inverter are closely related depending on the output load connecting state, a distorted space vector can occur when the neutral point voltage of a 3-level NPC inverter is unbalanced. The proposed method can improve the distorted space vectors by adjusting the injection time of the small and medium vectors and by modulating the amplitude of the carrier waveforms. In this paper, the proposed method is verified by both simulation and experimental results based on a 3-level NPC inverter. [ABSTRACT FROM AUTHOR]

Organic nonlinear optical salt crystals are widely used as efficient broadband THz generators. Although solid state molecular motions of organic crystals can greatly influence THz generation characteristics, their origin and effects on THz photonics are not clearly identified. In this work, the origin of solid‐state molecular motions of the state‐of‐the‐art nonlinear optical organic salt crystals and their effects on THz generation characteristics are theoretically investigated. A model crystal, HMQ‐TMS (2‐(4‐hydroxy‐3‐methoxystyryl)‐1‐methylquinolinium 2,4,6‐trimethylbenzenesulfonate) with large macroscopic optical nonlinearity, which is very attractive for intense broadband and narrowband THz wave generation, is chosen. The solid‐state molecular vibrations of HMQ‐TMS crystals can be classified in three frequency regions: phonon mode region, intramolecular motion region, and their mixing region. For the first time for ionic organic crystalline THz generators, the contributions of cationic chromophores and anionic matchmakers on each of vibrational modes are quantitatively separated. In addition, the influence of solid‐state molecular vibrations of HMQ‐TMS crystals on the generated THz spectra is investigated. These results provide an essential information for design of new organic nonlinear optical salt crystals for THz generators as well as detectors and for optimization of THz generation performance. [ABSTRACT FROM AUTHOR]

A new approach for the molecular design of highly efficient nonlinear optical organic crystals is proposed by introducing substituents that form σ‐holes on both nonlinear optical cationic chromophores and aromatic anions. Introducing chlorinated substituents, in which a relatively positive σ‐hole and a negative belt coexist, provides selective reduction capability of specific π–π intermolecular interactions and simultaneous multiple secondary bonding capabilities. This leads to a crystalline state with enhanced first‐order hyperpolarizability βcrystal of chromophores that favors parallel chromophore alignment and suppression of molecular vibrations, which are optimal characteristics for electro‐optic and nonlinear optical applications, including efficient THz wave generation. Compared to benchmark nonhalogenated and fluorinated analogous crystals with state‐of‐the‐art macroscopic optical nonlinearity, σ‐hole containing chloro‐quinolinium crystals exhibit up to two times higher macroscopic nonlinear optical response and remarkably different crystal characteristics. As a result, a 0.16 mm thick chloro‐quinolinium crystal exhibits ≈22 times higher optical‐to‐THz conversion efficiency than the widely used 1.0 mm thick ZnTe inorganic crystal. Moreover, chloro‐quinolinium crystals exhibit very broad THz spectra, up to 8 THz with significantly different THz spectral shape compared to benchmark organic crystals, which is attributed to different phase matching between optical and THz frequencies and molecular vibration motions. [ABSTRACT FROM AUTHOR]

Background and Objectives: Zonulin is a human protein that regulates intercellular tight junctions and increases the permeability of the intestinal epithelium. In light of the increasing focus on zonulin's role in numerous chronic inflammatory diseases, this study aimed to investigate whether differences exist in serum zonulin levels and bronchial epithelium zonulin expression in vivo between asthma and normal groups, using a mouse model. Methods: Sixteen mice were utilized in this study, divided evenly between the normal and asthma groups. Serum zonulin levels, the expression of zonulin antibody in the bronchial epithelium, and serum cytokine levels were evaluated in both groups. Enzyme-linked immunosorbent assay and RNA in situ hybridization were utilized for the analysis. Results: The asthma group exhibited significantly higher levels of serum zonulin. High zonulin antibody expression was also observed in the bronchial epithelium of the asthma group. Given that our mouse model demonstrated a significant difference in interleukin (IL)-4 and IL-6 between the normal and asthma groups, zonulin may be associated not only with type 2 responses but also with various subtypes of asthma. Further studies are required to investigate this relationship in greater detail. Conclusion: Zonulin may play a role in the complex pathophysiology of asthma and could serve as a biomarker in various asthma-related situations. [ABSTRACT FROM AUTHOR]

Background and Objectives: Some patients experiencing dizziness also report psychological distress. However, the association between vestibular deficits and psychological symptoms remains controversial. Thus, the aim of this paper is to report the proportion of patients who complained of dizziness who also had high depression and anxiety indices. Also we investigated the severity of their dizziness and the distribution of the diseases underlying this symptom. Subjects and Methods: We assessed the dizziness and psychological distress of 544 patients experiencing dizziness using the Korean versions of the Dizziness Handicap Inventory (DHI), the Beck Depression Inventory (BDI), and the Spielberger State-Trait Anxiety Inventory (STAI). We also reviewed the audio-vestibular symtoms of patients with high levels of depression and anxiety. Results: The incidences of high depression and anxiety scores were 11% (60/544) and 18% (98/544), respectively. Patients with vestibular migraine were most likely to have high depression and anxiety indices. Patients in the high-BDI or high-STAI groups (117/544) obtained significantly higher DHI scores than those in neither the high-BDI nor the high-STAI group (427/544). We noticed that about 20% of the patients experiencing dizziness had high levels of psychological distress in this study; this group also suffered from various vestibular diseases and more symptoms of dizziness. Conclusions: The results of the study suggest that psychological evaluation should be considered when assessing patients with vertigo. [ABSTRACT FROM AUTHOR]