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Background and purpose: Germinal centers (GCs) can be observed in the thymic tissues of patients with thymoma‐associated myasthenia gravis (MG). Although an association between thymic GCs and MG has been suggested, it is unknown whether the presence of GCs could predict the development of MG after the resection of thymoma, known as postthymectomy MG. Methods: We conducted a retrospective analysis of previously nonmyasthenic patients who underwent surgical removal of the thymoma. All available thymic tissue slides were rereviewed by a pathologist to assess for GCs. Patients were classified into GC‐positive and GC‐negative groups based on the presence of GCs. The incidence of postthymectomy MG was compared between the two groups, and the risk factors for postthymectomy MG were assessed. Results: Of the 196 previously nonmyasthenic patients who underwent thymoma resection, 21 were GC‐positive, whereas 175 were GC‐negative. Postthymectomy MG developed in 11 (5.6%) patients and showed a higher incidence in the GC‐positive group than in the GC‐negative group (33.3% vs. 2.3%, p < 0.001). No postoperative radiotherapy and the presence of GCs were risk factors for postthymectomy MG in the univariate analysis. In multivariate analysis, invasive thymoma (hazard ratio [HR] = 9.835, 95% confidence interval [CI] = 1.358–105.372), postoperative radiotherapy (HR = 0.160, 95% CI = 0.029–0.893), and presence of GCs (HR = 15.834, 95% CI = 3.742–67.000) were significantly associated with postthymectomy MG. Conclusions: Thymic GCs may be a significant risk factor for postthymectomy MG. Even in patients with thymoma who do not show clinical symptoms of MG, postthymectomy MG should be considered, especially if thymic GCs are observed. [ABSTRACT FROM AUTHOR]

Blade coating of perovskite solar cells (PSCs) and modules has progressed considerably toward the industrial production of perovskite photovoltaics. Developing stable perovskite precursors is critical for achieving uniform coating over large areas. Here, the engineering of a perovskite precursor solution consisting of 2‐methoxyethanol (2‐Me) and 1,3‐dimethyl‐imidazolidinone (DMI) with superior intermediate phase stability that enables scalable production of efficient perovskite solar modules is reported. With this perovskite precursor solution, uniform and pinhole‐less perovskite film is deposited over a large area of > 100 cm2 and higher‐efficiency PSCs and modules are obtained. The best‐performing unit cell and module with n‐i‐p configuration reach power conversion efficiencies of 23.4% and 20.1%, respectively. Additionally, a series of non‐destructive metrology methods, such as spectroscopic ellipsometry, hyperspectral photoluminescence, electroluminescence, and laser beam‐induced current mapping, are employed to assess and guide the development the blade‐coated perovskite modules. This results show that rational engineering of precursor inks for blade coating is promising for the scalable production of efficient perovskite solar modules. [ABSTRACT FROM AUTHOR]

Wood is a naturally abundant, renewable, recyclable, biodegradable, and environment‐friendly construction material. Smart homes capable of remote monitoring and light, climate, and appliance control require a large number of electrical sensors and interconnections, which are challenging to implement in wood. Although conductive Laser‐induced‐graphene (LIG) formation on lignocellulosic materials has been lately reported, the introduction of LIG electrodes to smart wooden home applications has not been addressed to date. Herein, the direct patterning of LIG on natural wood in atmospheric air to form key electrical components that can support the construction of smart wooden homes is demonstrated. The sheet resistance of the LIG can reach 6.0 Ω sq−1, which is sufficient to support smart home requirements. Four key smart home components, namely, a temperature sensor, heater, boiler, and electrical interconnections, are successfully patterned on wood at room temperature without significant ablation. In consideration of the real‐world application of this technology to wooden buildings, varnish coating is used for the LIG's structural protection; all the tests are conducted repeatedly by considering the actual wooden smart home applications. The design of LIG electrical connections using an external mechanical pressure without conductive adhesives will help promote the development of green and smart adhesive‐free timber‐based buildings. [ABSTRACT FROM AUTHOR]

Laser‐induced graphene (LIG) is a newly emerging 3D porous material produced when irradiating a laser beam on certain carbon materials. LIG exhibits high porosity, excellent electrical conductivity, and good mechanical flexibility. Predesigned LIG patterns can be directly fabricated on diverse carbon materials with controllable microstructure, surface property, electrical conductivity, chemical composition, and heteroatom doping. This selective, low‐cost, chemical‐free, and maskless patterning technology minimizes the usage of raw materials, diminishes the environmental impact, and enables a wide range of applications ranging from academia to industry. In this review, the recent developments in 3D porous LIG are comprehensively summarized. The mechanism of LIG formation is first introduced with a focus on laser‐material interactions and material transformations during laser irradiation. The effects of laser types, fabrication parameters, and lasing environment on LIG structures and properties are thoroughly discussed. The potentials of LIG for advanced applications including biosensors, physical sensors, supercapacitors, batteries, triboelectric nanogenerators, and so on are also highlighted. Finally, current challenges and future prospects of LIG research are discussed. [ABSTRACT FROM AUTHOR]

Semiconductor devices have become smaller, more complicated, and structuralized in three dimensions. Area selective deposition is one of the promising bottom‐up process techniques for self‐alignment or improved overlay to achieve errorless alignment. The surface chemistry is crucial to adjust precursor adsorption. In this research, graphitic carbon fabricated by molecular layer deposition is utilized for inhibiting precursor adsorption. An indicone film, which has an indium‐based metalcone structure, is fabricated using bis(trimethysily)‐amidodiethylindium and hydroquinone. The structure of the indicone film is reconstructed to graphitic carbon with a small oxygen content on the surface by a thermal annealing process. The atomic structures of as‐dep and thermally‐annealed indicone films are analyzed. The organic structure is transformed to graphitic carbon above an annealing temperature of 450 °C, where indium is completely removed with annealing temperatures above 600 °C. The thermally‐annealed indicone is used for deactivating film growth, which can delay 60 cycles of ZnO growth (equivalent to a thickness of ≈11 nm). In addition, to energetically demonstrate precursor adsorption on graphitic carbon, the density functional theory is utilized. Finally, ZnO as a blocking layer is selectively deposited on a grated line pattern to interconnect the SiO2 line pattern by transferring a hard mask. [ABSTRACT FROM AUTHOR]

The development of green flexible micro‐supercapacitors (MSCs) is one of the biggest challenges in future wearable electronics. Flexible MSCs are mainly produced from non‐biodegradable synthetic polymers, resulting in massive electronic waste. Moreover, complex multi‐step fabrication increases their production cost. Here, the direct fabrication of highly conductive, intrinsically flexible, and green microelectrodes from naturally fallen leaves in ambient air using femtosecond laser pulses without any additional materials is reported. Hierarchically porous graphene is patterned on different types of leaves via a facile, mask‐less, scalable, and one‐step laser writing. Leaves consist of biominerals, which decompose into inorganic crystals that serve as nucleation sites for the growth of 3D mesoporous few‐layer graphene. The femtosecond laser‐induced graphene (FsLIG) microelectrodes formed on leaves have lower sheet resistance (23.3 Ω sq−1) than their synthetic polymer counterparts and exhibit an outstanding areal capacitance (34.68 mF cm−2 at 5 mV s−1) and capacitance retention (≈99% after 50 000 charge/discharge cycles). The FsLIG MSCs on a single leaf could easily power a light‐emitting diode or a table clock and could be applied in wearable electronics, smart houses, and Internet of Things. [ABSTRACT FROM AUTHOR]

Metal microhoneycomb structures have received considerable attention as a type of interaction‐efficient functional devices owing to their unique morphology and material properties. Microhoneycomb structures are mainly fabricated using the well‐known breath‐figure method. However, additional post‐treatments are required to produce a metal structure because it is a polymer‐based process, and this necessitates expensive, complex, and multi‐step fabrication processes. Therefore, a simple, low‐cost metal honeycomb fabrication process is necessary. In this paper, the laser patterning of an organometallic solution to produce silver microhoneycomb (Ag microhoneycomb) structures is proposed. Various phenomena such as rapid organic evaporation, silver nanoparticle solidification, and material reorganization from Marangoni flow are found to enable patterning‐induced microhoneycomb formation. Parametric studies demonstrate that the pore size can be easily controlled through simple laser parameter changes. In addition, cyclic voltammetry and electrochemical impedance spectroscopy studies confirm the potential electrochemical applications of the Ag microhoneycomb structures based on the variation of electrochemical redox behavior depending on the pore size. Owing to the excellent advantages of one‐step laser patterning without any templates, the proposed process will likely promote the practical use of the metal microhoneycomb structures. [ABSTRACT FROM AUTHOR]

We introduce an efficient method for the immobilization of phenolic compounds, based on 1,2,4,‐triazoline‐3,5‐dione (TAD), which selectively reacts with phenolic compounds at the α position to the phenolic hydroxyl group, ensuring intact phenol functionality, and therefore, maintaining the biological activity of the phenolic compound. We prepared self‐assembled monolayers on gold that presented urazole (the reduced form of TAD) as the terminal group and which were activated electrochemically without treatment with chemical oxidants, allowing on‐demand activation and in situ immobilization of the phenolic compounds. We examined the immobilization of various phenolic compounds and verified the surface chemistry using electrochemistry and mass spectrometry. The proposed method is simple and straightforward and does not require complicated protocols and reagents, and thus, it can be a general and practical platform for the immobilization of phenol‐containing molecules on the surfaces of various materials. [ABSTRACT FROM AUTHOR]

Perovskite solar cells in an n‐i‐p structure record high power conversion efficiency, but issues of insufficient thermal stability and the high cost of p‐type hole transporting materials have been raised as drawbacks. H2‐phthalocyanine (Pc) is introduced as a hole transport material to ensure the thermal stability and simultaneously have served surface passivation effects on hybrid halide perovskites as a Lewis base. Pyrrolic nitrogen in the Pc reacts with uncoordinated Pb2+ ions on the perovskite surface. Upon enhancing the interfacial interaction between phthalocyanine and the perovskite, the open circuit voltage in devices increases as compared to that of devices using a metal‐phthalocyanine complex. While the phthalocyanine‐applied device maintains superior thermal long‐term stability, the power conversion efficiency also exceeds 20%. [ABSTRACT FROM AUTHOR]

We investigated the clinical, laboratory, and genetic spectra in Korean patients with dysferlinopathy to clarify its genotype–phenotype correlation. We retrospectively reviewed 101 patients from 96 unrelated families with pathogenic variants of DYSF. The most common initial phenotype was Miyoshi myopathy in 50 patients. Median ages at examination and symptom onset were 23 [interquartile range (IQR): 18–30] and 36 years [IQR: 27–48], respectively. We observed 38 variants, including nine novel variants. Four variants (c.2494C > T, c.1284 + 2 T > C, c.663 + 1G > C, and c.2997G > T) in DYSF accounted for 62% of total allele frequencies of pathogenic variants. To analyze the genotype–phenotype correlation, we compared the clinical phenotype between patients with null/null (N/N; n = 55) and null/missense variants (N/M; n = 35). The N/N group had an earlier symptom onset age (median: 20 years [IQR: 17–25]) than the N/M group (median: 29 years [IQR: 23–35], p <.001). Total manual muscle testing scores in lower extremities were lower in the N/N group (median: 80 [IQR: 56–92]) than in the N/M group (median: 89 [IQR: 78–98], p =.013). Our study is the first to report that null variants in DYSF result in an earlier symptom onset than missense variants. [ABSTRACT FROM AUTHOR]

Objective: Myelinated Schwann cells (SCs) in adult peripheral nerves dedifferentiate into immature cells in demyelinating neuropathies and Wallerian degeneration. This plastic SC change is actively involved in the myelin destruction and clearance as demyelinating SCs (DSCs). In inherited demyelinating neuropathy, pathologically differentiated and dysmyelinated SCs constitute the main nerve pathology. Methods: We investigated whether this SC plastic status in human neuropathic nerves could be determined by patient sera to develop disease‐relevant serum biomarkers. Based on proteomics analysis of the secreted exosomes from immature SCs, we traced p75 neurotrophin receptor (p75) and neural cell adhesion molecule 1 (NCAM) in the sera of patients with peripheral neuropathy. Results: Enzyme‐linked immunosorbent assay (ELISA) revealed that p75 and NCAM were subtype‐specifically expressed in the sera of patients with peripheral neuropathy. In conjunction with these ELISA data, pathological analyses of animal models and human specimens suggested that the presence of DSCs in inflammatory neuropathy and of supernumerary nonmyelinating or dysmyelinating SCs in inherited neuropathy could potentially be distinguished by comparing the expression profiles of p75 and NCAM. Interpretation: This study indicates that the identification of disease‐specific pathological SC stages might be a valuable tool for differential diagnosis of peripheral neuropathies. [ABSTRACT FROM AUTHOR]

Introduction: Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) patients possess multiple risk factors for osteoporosis, but few studies have evaluated bone mineral density (BMD) in CIDP patients.Methods: We retrospectively compared the BMD of CIDP patients with that of normal controls, and evaluated the clinical factors associated with osteoporosis.Results: Total BMD was lower in CIDP patients than in normal controls (P = 0.017). In a comparison of 16 osteoporotic CIDP patients with 25 non-osteoporotic patients, the cumulative prednisolone dose was lower (P = 0.022) and the duration from disease onset to BMD measurement was shorter (P = 0.014) in osteoporotic patients than in non-osteoporotic patients. Function, as measured by modified Rankin scale score within 3 years of the BMD measurement, was worse in osteoporotic than in non-osteoporotic patients (P = 0.008).Discussion: BMD in CIDP patients was significantly lower than in normal controls. Functional status rather than cumulative steroid dose was associated with osteoporosis. Muscle Nerve 58: 407-412, 2018. [ABSTRACT FROM AUTHOR]

A non-metal approach for accessing α-oxo carbene surrogates for a C−C bond-forming bimolecular coupling between ynamides and nucleophilic arenes was developed. This acid-catalyzed coupling features mild temperature, which is critical for the required temporal chemoselectivity among nucleophiles. The scope of nucleophiles includes indoles, pyrroles, anilines, phenols and silyl enolethers. Furthermore, a direct test of SN2′ mechanism has been provided by employing chiral N,N′-dioxides which also enlightens the nature of the intermediates in related metal-catalyzed processes. [ABSTRACT FROM AUTHOR]

Objective We performed a retrospective, prognostic analysis of a cohort of patients with epilepsy according to time of relapse after four seizure-free years. Methods Planned withdrawal of antiepileptic drugs ( AEDs) and at least 3 years of follow-up after AED discontinuation were performed. The following two groups were assessed: (1) an early relapse ( ER) group of patients who experienced recurrence during AED withdrawal and (2) a late relapse ( LR) group of patients who experienced recurrence after completion of the AED discontinuation process. After dichotomization, the relapse rate, prognostic factors, and their impacts for each group were compared with those of a group of patients who continued to be seizure-free after AED withdrawal ( SF group) using multiple logistic regression analysis. The AED intake mode was also analyzed. Results Two hundred seventeen (64.6%) of the 336 total patients experienced relapse. One hundred thirty-nine patients (41.4%) and 78 patients (23.2%) were included in the LR and ER groups, respectively. Symptom duration >120 months showed the strongest negative prognostic impact as demonstrated by the 4.7-fold higher risk of recurrence in the ER group compared with the SF group. Additional factors with a negative prognostic impact included an age at epilepsy onset of ≤20 years and the presence of localization-related epilepsy. No reliable predictor between the SF and LR groups was revealed. After exclusion of the SF group, post hoc analysis according to age at epilepsy onset and symptom duration showed that the above-mentioned negative prognostic factors significantly affected the relapse patterns of the LR and ER groups. Significance The results suggest that longer symptom duration, which could be associated with intrinsic reactivation of epilepsy, is the strongest negative prognostic factor for relapse. Relapse after AED withdrawal in prolonged follow-up of seizure-free patients is one aspect of the natural history of epilepsy. [ABSTRACT FROM AUTHOR]

ABSTRACT Background The purpose of this study was to identify the prevalence of sialoceles and the risk factors associated with their formation after parotidectomy. Methods We performed a retrospective analysis of the data from consecutive patients who underwent partial superficial parotidectomy of parotid tumors. Demographic data, preoperative imaging results, operative variables, including tumor type, incision type, tumor size, and method of parenchymal disruption were assessed. Results Twenty-three of 357 patients (6.4%) undergoing partial superficial parotidectomy developed sialoceles during the postoperative period. Sialoceles occurred more often in patients who had tumors in the anterior portion of the parotid gland. Multivariate analysis showed that an anterior tumor location was a significant risk factor for sialocele formation. Conclusion The incidence of sialocele development was 6.4% in patients undergoing partial superficial parotidectomy. An anterior tumor location may increase the risk of sialocele formation. © 2015 Wiley Periodicals, Inc. Head Neck 38: E941-E944, 2016 [ABSTRACT FROM AUTHOR]

Recent experimental data of high-order harmonic generation (HHG), obtained by use of the plasmonic field enhancement of nanostructure bowties and funnel-waveguides, are presented. Emphasis is laid on reproduction of previous experimental results and also elucidation of the fundamental limitations associated with the nanostructure thermal damage, small laser-gas interaction volume, and atomic line emission in the plasmon-driven HHG process. In addition, the dominance of coherent harmonics is quantitatively verified by implementing a two-beam interference experiment using a pair of funnel-waveguides. This study proves that funnel-waveguides are a superior plasmonic device capable of providing not only high thermal immunity but also sufficient atom emitters to produce practically usable extreme-ultraviolet (EUV) radiation in a reproducible manner. [ABSTRACT FROM AUTHOR]

As a new area of biological integration systems ranging from fitness to costume, arable electronic devices are extensively investigated and recently focused on the development of customized and highly interactive devices with human‐friendly factors. Here, a facile method of integrating a three‐dimensional printing (3DP) with stretchable and conductive nanocomposite materials to form a multiaxial piezoresistive sensor that can detect human motion is presented. The multiaxial piezoresistive sensors are fabricated through direct 3DP of nanocomposites based on graphene nanoplatelets (GNPs), silver nanoparticles (AgNPs), and polyurethane. The sensor can detect not only compression, but also tensile strain upto more than 160%. Based on the synergy between GNPs and AgNPs, the sensor shows high sensitivity with a gauge factor of 48.2, which is a much higher value considering that most of the previously reported stretchable strain sensors are less than 35. In addition to the high sensitivity, the GNPs/AgNPs nanocomposite sensor exhibits a fast response time and excellent stability over 500 cycles. When the sensor is integrated into an LED light system, it functions as an interactive device that can control the intensity of light by detecting various human motions such as the bending of fingers. A facile method for fabrication of a multiaxial piezoresistive sensor via integrating a 3D printing (3DP) with stretchable and conductive nanocomposite materials is demonstrated. This sensor can detect tensile deformation as well as compression, and shows fast response time and excellent stability. It provides an interesting perspective on creating 3DP sensors with diverse geometry and multi‐axis detection. [ABSTRACT FROM AUTHOR]

The article presents a case study of an 81-year-old man diagnosed with extraparotid warthin tumor (WT) in upper cervical lymph node accompanied by primary cervical tuberculosis. The enhanced neck computed tomography (CT) of the patient revealed a heterogeneously enhanced mass, just posterior to the right submandibular gland. It states that the low-power microscopic specimen showed that the lymph node was mostly replaced by the WT.