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Single-photon emitters, the basic building blocks of quantum communication and information, have been developed using atomically thin transition metal dichalcogenides (TMDCs). Although the bandgap of TMDCs was spatially engineered in artificially created defects for single-photon emitters, it remains a challenge to precisely align the emitter's dipole moment to optical cavities for the Purcell enhancement. Here, we demonstrate position- and polarization-controlled single-photon emitters in monolayer WSe2. A tensile strain of ∼0.2% was applied to monolayer WSe2 by placing it onto a dielectric rod structure with a nanosized gap. Excitons were localized in the nanogap sites, resulting in the generation of linearly polarized single-photon emission with a g(2) of ∼0.1 at 4 K. Additionally, we measured the abrupt change in polarization of single photons with respect to the nanogap size. Our robust spatial and polarization control of emission provides an efficient way to demonstrate deterministic and scalable single-photon sources by integrating with nanocavities.

Very recently, stacked two-dimensional materials are studied, focusing on the van der Waals interaction at their stack junction interface. Here, we report field effect transistors (FETs) with stack...

Objective The purpose of this study was to compare the outcomes of coil embolization using a 0.009 inches primary outer diameter coil as finishing coil (FC) to that of 0.01 inches. Methods From February and August 2020, 131 aneurysms that performed coil embolization using FC with a second loop diameter of 1 mm, were reviewed retrospectively, conducting propensity score matching and logistic regression analysis. Angiographic results such as, occlusion grade, packing density, failure and event were compared between 0.009 inches coil of GALAXY G3™ MINI microcoil (n = 54) and 0.01 inches coils (n = 77). Results There were no statistically significant differences between two groups, but more events occurred in the 0.009 group. (Odds ratio, 3.65; 95% CI, 1.06-12.55; P = 0.031) In the results of coil embolization, successful occlusion occlusion (complete occlusion and residual neck) was identified more in the 0.01 group. After propensity score matching, the variables in each group were similar, but the successful occlusion was higher in the 0.01 group as in the total population. Events tended to occur more frequently in the 0.009 inch group, and logistic regression analysis showed slightly higher events in the angled microcatheter. (48.3% versus 76.9%., P = 0.075), Also, the 0.009 inch FC is an independent risk factor. (Odds ratio, 3.84; 95% CI, 1.07-13.80; P = 0.039) Conclusions Using 0.01 inches coils as FC increased the packing density after the procedure, and showed more successful occlusion than using a 0.009 inches coil. The probability of unexpected events was observed more than three times in the 0.009 inch group.

Very recently, stacked two-dimensional materials have been studied, focusing on the van der Waals interaction at their stack junction interface. Here, we report field effect transistors (FETs) with stacked transition metal dichalcogenide (TMD) channels, where the heterojunction interface between two TMDs appears useful for nonvolatile or neuromorphic memory FETs. A few nanometer-thin WSe

In optoelectronic devices based on two-dimensional (2D) semiconductor heterojunctions, the efficient charge transport of photogenerated carriers across the interface is a critical factor to determine the device performances. Here, we report an unexplored approach to boost the optoelectronic device performances of the WSe

It is important to obtain sufficient bone mass before implant placement on alveolar bone, and synthetic bone such as biphasic calcium phosphate (BCP) has been studied to secure this. This study used a BCP block bone with a specific structure of the three-dimensional (3D) hexahedron channel and coating with recombinant human bone morphogenetic protein-2 (rhBMP-2) impregnated carboxymethyl cellulose (CMC) was used to examine the enhancement of bone regeneration of this biomaterial in rat calvarial defect. After the preparation of critical-size calvarial defects in fifteen rats, defects were divided into three groups and were implanted with the assigned specimen (n = 5): Boneplant (untreated 3D hexahedron channeled BCP block), Boneplant/CMC (3D hexahedron channeled BCP block coated with CMC), and Boneplant/CMC/BMP (3D hexahedron channeled BCP block coated with CMC containing rhBMP-2). After 4 weeks, the volumetric, histologic, and histometric analyses were conducted to measure the newly formed bone. Histologically, defects in the Boneplant/CMC/BMP group were almost completely filled with new bone compared to the Boneplant and Boneplant/CMC groups. The new bone volume (P &lt, 0.05) and area (P &lt, 0.001) in the Boneplant/CMC/BMP group (20.12% &plusmn, 2.17, 33.79% &plusmn, 3.66) were much greater than those in the Boneplant (10.77% &plusmn, 4.8, 16.48% &plusmn, 9.11) and Boneplant/CMC (10.72% &plusmn, 3.29, 16.57% &plusmn, 8.94) groups, respectively. In conclusion, the 3D hexahedron channeled BCP block adapted rhBMP-2 with carrier CMC showed high possibility as an effective bone graft material.

A man visited the emergency room with a headache. Brain computed tomography showed aneurysmal subarachnoid hemorrhage (SAH) and multiple aneurysms. After aneurysm clipping surgery, the patient was discharged. After 5 days, he was admitted to the hospital with skin ulceration and was diagnosed with Behcet syndrome. An angiogram taken 7 weeks after aneurysmal SAH showed intracranial vasospasm. Because inflammation in Behcet syndrome may aggravate intracranial vasospasm, intracranial vasospasm after aneurysmal SAH in Behcet syndrome should be monitored for longer compared to general aneurysmal SAH.

The memristor, a composite word of memory and resistor, has become one of the most important electronic components for brain-inspired neuromorphic computing in recent years. This device has the ability to control resistance with multiple states by memorizing the history of previous electrical inputs, enabling it to mimic a biological synapse in the neural network of the human brain. Among many candidates for memristive materials, including metal oxides, organic materials, and low-dimensional nanomaterials, 2D layered materials have been widely investigated owing to their outstanding physical properties and electrical tunability, low-power-switching capability, and hetero-integration compatibility. Hence, a large number of experimental demonstrations on 2D material-based memristors have been reported showing their unique memristive characteristics and novel synaptic functionalities, distinct from traditional bulk-material-based systems. Herein, an overview of the latest advances in the structures, mechanisms, and memristive characteristics of 2D material-based memristors is presented. Additionally, novel strategies to modulate and enhance the synaptic functionalities of 2D-memristor-based artificial synapses are summarized. Finally, as a foreseeing perspective, the potentials and challenges of these emerging materials for future neuromorphic electronics are also discussed.

Ultralow power chemical sensing is essential toward realizing the Internet of Things. However, electrically driven sensors must consume power to generate an electrical readout. Here, a different class of self-powered chemical sensing platform based on unconventional photovoltaic heterojunctions consisting of a top graphene (Gr) layer in contact with underlying photoactive semiconductors including bulk silicon and layered transition metal dichalcogenides is proposed. Owing to the chemically tunable electrochemical potential of Gr, the built-in potential at the junction is effectively modulated by absorbed gas molecules in a predictable manner depending on their redox characteristics. Such ability distinctive from bulk photovoltaic counterparts enables photovoltaic-driven chemical sensing without electric power consumption. Furthermore, it is demonstrated that the hydrogen (H2 ) sensing properties are independent of the light intensity, but sensitive to the gas concentration down to the 1 ppm level at room temperature. These results present an innovative strategy to realize extremely energy-efficient sensors, providing an important advancement for future ubiquitous sensing.

Vertebral artery hypoplasia (VAH) can be easily overlooked if the contralateral side vertebral artery is intact, because of compensation by the contralateral artery or cerebral collateral network. The clinical relevance and hemodynamic impact of VAH is still controversial. However, VAH has recently been considered a risk factor for posterior circulation ischemia. Ischemic stroke is seldom caused by free floating thrombi (FFT) in the artery. Pathophysiology of FFT has not yet been clarified. The state of reduced blood flow such as a vertebral artery origin stenosis may cause FFT. Their instability may make them sources of recurrent artery to artery embolism. Patients with FFT will require appropriate medical and endovascular treatment. The current case illustrates a short-term angiographic change of spontaneous thrombolysis of VAH and multiple thrombi at the distal region of the stenosed lesion after stent-assisted angioplasty for a vertebral artery origin stenosis.

Heterojunction catalyst can facilitate efficient photoelectrochemical (PEC) hydrogen evolution by reducing a potential barrier for charge transfer at the semiconductor/electrolyte interface. Such a heterojunction effect at the atomic thickness limit has not yet been explored although it can be strengthened because of strong built-in field and ultrafast charge transfer across the junction. Here, we first investigate a novel strategy to boost the hydrogen evolution performance of the p-type WSe2 photocathode via reducing the overpotential with an atomically thin heterojunction catalyst comprising MoS2 and WS2 monolayers. To unveil an effective role of the heterojunction by isolating its kinetic contribution from other collective catalytic effects, we develop and utilize an in situ scanning PEC microscopy, which enables the spatially-resolved visualization of the enhanced photocatalytic hydrogen evolution performance of the heterojunction. Notably, significant reduction in overpotential, from +0.28 ± 0.03 to −0.04 ± 0.05 V versus (vs.) the reversible hydrogen electrode (RHE), is achieved when the MoS2/WS2 heterojunction is introduced as a catalyst even without intentional generation of catalytic sites. As a result, the photocurrent of ~4.0 mA cm−2 occurs even at 0 V vs. RHE. Furthermore, the beneficial effect of the atomically scaled vertical heterojunction is explained by the built-in potential resulted from efficient charge transfer in type-II heterojunctions with the support of first-principles calculations. Our demonstration not only offers an unprecedented approach to investigating the fundamental PEC characteristics in relation to the tailored properties of a catalyst but also proposes a new catalytic architecture, thereby enabling the design of highly efficient PEC systems.

Purpose The authors developed a video image-guided real-time patient motion monitoring (VGRPM) system using PC-cams, and its clinical utility was evaluated using a motion phantom. Methods The VGRPM system has three components: (1) an image acquisition device consisting of two PC-cams, (2) a main control computer with a radiation signal controller and warning system, and (3) patient motion analysis software developed in-house. The intelligent patient motion monitoring system was designed for synchronization with a beam on/off trigger signal in order to limit operation to during treatment time only and to enable system automation. During each treatment session, an initial image of the patient is acquired as soon as radiation starts and is compared with subsequent live images, which can be acquired at up to 30 fps by the real-time frame difference-based analysis software. When the error range exceeds the set criteria (δ(movement)) due to patient movement, a warning message is generated in the form of light and sound. The described procedure repeats automatically for each patient. A motion phantom, which operates by moving a distance of 0.1, 0.2, 0.3, 0.5, and 1.0 cm for 1 and 2 s, respectively, was used to evaluate the system performance. The authors measured optimal δ(movement) for clinical use, the minimum distance that can be detected with this system, and the response time of the whole system using a video analysis technique. The stability of the system in a linear accelerator unit was evaluated for a period of 6 months. Results As a result of the moving phantom test, the δ(movement) for detection of all simulated phantom motion except the 0.1 cm movement was determined to be 0.2% of total number of pixels in the initial image. The system can detect phantom motion as small as 0.2 cm. The measured response time from the detection of phantom movement to generation of the warning signal was 0.1 s. No significant functional disorder of the system was observed during the testing period. Conclusions The VGRPM system has a convenient design, which synchronizes initiation of the analysis with a beam on/off signal from the treatment machine and may contribute to a reduction in treatment error due to patient motion and increase the accuracy of treatment dose delivery.

The development of energy-efficient artificial synapses capable of manifoldly tuning synaptic activities can provide a significant breakthrough toward novel neuromorphic computing technology. Here, a new class of artificial synaptic architecture, a three-terminal device consisting of a vertically integrated monolithic tungsten oxide memristor, and a variable-barrier tungsten selenide/graphene Schottky diode, termed as a 'synaptic barrister,' are reported. The device can implement essential synaptic characteristics, such as short-term plasticity, long-term plasticity, and paired-pulse facilitation. Owing to the electrostatically controlled barrier height in the ultrathin van der Waals heterostructure, the device exhibits gate-controlled memristive switching characteristics with tunable programming voltages of 0.2-0.5 V. Notably, by electrostatic tuning with a gate terminal, it can additionally regulate the degree and tuning rate of the synaptic weight independent of the programming impulses from source and drain terminals. Such gate tunability cannot be accomplished by previously reported synaptic devices such as memristors and synaptic transistors only mimicking the two-neuronal-based synapse. These capabilities eventually enable the accelerated consolidation and conversion of synaptic plasticity, functionally analogous to the synapse with an additional neuromodulator in biological neural networks.

Isolated cortical venous thrombosis is very rare and poorly understood. The clinical presentation is also not well described in the literature. We report here a case of isolated cortical venous thrombosis that mimicked cortical subarachnoid hemorrhage (SAH). A 62-year-old man with a history of chronic subdural hemorrhage visited our hospital with headache. Brain computed tomography (CT) revealed a linear hyperdense area in the right central sulcus (cord sign), suggestive of isolated cortical SAH. Magnetic resonance imaging (MRI) revealed susceptibility in the corresponding area. CT angiography revealed no specific finding. However, transfemoral cerebral angiography (TFCA) identified filling defects in the right cortical veins. Under isolated cortical venous thrombosis, anticoagulation therapy was used to prevent the propagation of thrombosis. The patient had no recurrence of symptoms. If a cord sign is present on noncontrast CT images, further studies (MRI/magnetic resonance venography or TFCA) should be performed in a step-wise manner. Such considerations could prevent a fatal outcome and poor prognosis.

Combined superficial temporal artery-middle cerebral artery anastomosis and encephalo-duro-arterio-galeo-synangiosis (EDAGS) were retrospectively compared with indirect bypass, EDAGS with or without inversion, in 134 hemispheres of 96 adult patients with non-hemorrhagic moyamoya disease (MMD) in terms of angiographic findings, perioperative complications, and clinical outcome. Angiographic revascularization seemed to be better in the combined bypass group compared with the EDAGS group (p = 0.045), but perioperative complication tended to be slightly more common in the combined bypass group. No statistical differences were found in clinical outcome. EDAGS is a very reliable alternative to combined bypass in adult MMD. However, randomized clinical trials are needed to assess the long-term efficacy of any bypass surgery in adult patients with MMD.

The authors developed a video image-guided real-time patient motion monitoring (VGRPM) system using PC-cams, and its clinical utility was evaluated using a motion phantom.The VGRPM system has three components: (1) an image acquisition device consisting of two PC-cams, (2) a main control computer with a radiation signal controller and warning system, and (3) patient motion analysis software developed in-house. The intelligent patient motion monitoring system was designed for synchronization with a beam on/off trigger signal in order to limit operation to during treatment time only and to enable system automation. During each treatment session, an initial image of the patient is acquired as soon as radiation starts and is compared with subsequent live images, which can be acquired at up to 30 fps by the real-time frame difference-based analysis software. When the error range exceeds the set criteria (δ(movement)) due to patient movement, a warning message is generated in the form of light and sound. The described procedure repeats automatically for each patient. A motion phantom, which operates by moving a distance of 0.1, 0.2, 0.3, 0.5, and 1.0 cm for 1 and 2 s, respectively, was used to evaluate the system performance. The authors measured optimal δ(movement) for clinical use, the minimum distance that can be detected with this system, and the response time of the whole system using a video analysis technique. The stability of the system in a linear accelerator unit was evaluated for a period of 6 months.As a result of the moving phantom test, the δ(movement) for detection of all simulated phantom motion except the 0.1 cm movement was determined to be 0.2% of total number of pixels in the initial image. The system can detect phantom motion as small as 0.2 cm. The measured response time from the detection of phantom movement to generation of the warning signal was 0.1 s. No significant functional disorder of the system was observed during the testing period.The VGRPM system has a convenient design, which synchronizes initiation of the analysis with a beam on/off signal from the treatment machine and may contribute to a reduction in treatment error due to patient motion and increase the accuracy of treatment dose delivery.

An approach for the retrieval of price information from internet sites is applied to real-world application problems in this paper. The Web Information Retrieval System (WIRS) utilizes Hidden Markov Model (HMM) for its powerful capability to process temporal information. HMM is an extremely flexible tool and has been successfully applied to a wide variety of stochastic modeling tasks. In order to compare the prices and features of products from various web sites, the WIRS extracts prices and descriptions of various products within web pages. The WIRS is evaluated with real-world problems and compared with a conventional method and the result is reported in this paper.

A prediction scheme for sunspot series using a Multiscale Bilinear Recurrent Neural Network (M-BRNN) is proposed in this paper. The recurrent neural network adopted in this scheme is the Bilinear recurrent neural network. The M-BRNN is a combination of several Bilinear Recurrent Neural Network (BRNN) models. Each BRNN predicts a signal at a certain resolution level obtained by the wavelet transform. In order to evaluate the performance of the proposed M-BRNN-based predictor, experiments are conducted on the Wolf sunspot series number data and the resulting prediction accuracy is compared with those of conventional MultiLayer Perceptron Type Neural Network (MLPNN)-based and BRNN-based predictors. The results show that the proposed M-BRNN-based predictor outperforms the MLPNN-based and BRNN-based predictors in terms of the Normalized Mean Squared Error (NMSE).

We report six new cases of ischaemic stroke after cerebral haemorrhage in patients with moyamoya disease (MMD) and analyse their clinical and radiological characteristics, together with cases reported in the literature, to deduce the mechanism of cerebral infarct. Six (2%) of 246 patients with MMD who were admitted to our hospitals between 1993 and 2009 suffered cerebral infarct after intracranial haemorrhage. Ten patients identified in the literature with the PubMed search engine were also included in this study. All the ischaemic lesions in these 16 patients were analysed according to their location, size, and number and were compared according to the spatial relationship between the haemorrhage and infarct, as follows: (1) anterior vs posterior involvement, (2) cortical vs subcortical involvement, (3) watershed vs non-watershed infarct, (4) small vs large infarct, (5) single vs multiple infarct, and (6) adjacent vs distant involvement. Acute synchronous multiple brain infarcts occurred in six (38%) patients and recurrent infarcts in three patients (19%). Cerebral infarcts had mainly cortical (72%), anterior (66%), and distant involvement (75%) and were large (69%) and non-watershed (66%). Adjacent infarct had significantly anterior involvement (P

In this paper a simple signal segmentation algorithm is introduced. The algorithm determines the epochs of signal components of interest based on signal characteristic such as amplitude, slope, deflection width, or distance between neighboring deflections. The epochs are segmented indirectly by means of a slope trace wave that traces a signal with its average slope and predetermined delay. The algorithm is applied to ECG and electrogram to show its practical applicability and efficiency. It is found that the algorithm can be used to choose particular signal components appropriately without significant signal preprocessing or complexity.

This paper introduces a new approach to process biomedical signals by surgically removing wave deflections in time domain. The method first determines the epochs of high frequency deflections, cuts out them from the signal, and then connects the two disconnected points. To determine the epoch of a deflection to be removed, four slope trace waves are used to isolate the deflection based on signal characteristics of amplitude, slope, duration, and distance from neighboring deflections. The method has been applied to simulated data and MIT-BIH arrhythmia database to show its practical efficacy in the case of baseline wandering removal. It is found that the method has the capability to identify and remove high frequency deflections appropriately, leaving low frequency deflection such as baseline drifting.

Single-pass VDD pacemakers have been used as a result of simple implantation procedures and generally reliable atrial tracking. However, there is a controversy over their reliabilities of atrial tracking. As a new sensing method for reliable atrial tracking, a simple automatic pacemaker sensing, algorithm was implemented and evaluated to validate its benefits in sensing depolarization waves of single-pass VDD atrial electrograms. The automatic sensing algorithm had a predetermined sensing dynamic range and the sensitivity level was controlled as 50% of the average of two most recently sensed intrinsic amplitudes. The behavior of the automatic sensing algorithm in the single-pass VDD atrial electrograms was analyzed and characterized. It was observed that the automatic sensing algorithm was more effective than a conventional fixed threshold method to accurately detect and track p-waves in SVDD electrograms.

A pacemaker sensing algorithm is devised for p-wave detection in low SNR atrial electrograms. The algorithm uses three parameters, amplitude, slew rate, and p-p interval, and a fuzzy neural network structure is adopted to combine their characteristics. The signal characteristic of the current event is compared to those of three most recent p-waves, and the similarity and dissimilarity between them are used to determine if the event is a p-wave. In addition, the distributions of the characteristics of recent p-waves are considered such that a wider distribution takes a less synaptic weight.

Refractory hepatic hydrothorax has been treated by conservative methods: salt and water restriction, diuretics, thoracentesis, thoracostomy, and pleurodesis. The results, however, havebeen disappointing. Recently, TIPS has emerged as a new method for refractory hepatic hydrothorax, but it may lead to fatal complications. We report a case of refractory hepatic hydrothorax that was not treated by TIPS despite of successful control of ascitest.

The authors devised a pulse rate detection system to provide basic clinical index of cold-hot diagnosis of oriental medicine. The system consists of pulse signal detection, respiration signal detection, electrocardiograph detection, A/D conversion and computer system parts. The pulse rate, inspiration pulse rate and expiration pulse rate are defined as a pulse count in a respiration period, inspiration period and expiration period respectively. The clinical experiments on a normal person to evaluate the pulse rate detection system show a pulse/respiration ratio of 4.30/spl plusmn/1.03, a pulse/inspiration ratio of 1.60/spl plusmn/0.32, and a pulse/expiration ratio of 2.37/spl plusmn/0.75.

A recent light scattering cuvette has been successful in differentiating the type of microemboli in flowing whole blood. However, since the technique was designed assuming the microemboli are concentrated near the center of the scattering medium, it is necessary to investigate the effect of off-center locations on discrimination. The scattering intensities from 5 off-center locations were investigated and the type discrimination parameter (ratio of two forward scattering intensities) was calculated. The perturbation solution of radiative transport equation was used to describe the scattered intensity distribution in the scattering medium. In each location the parameter used for discrimination was not significantly altered since the overall cuvette geometry compensates for the scattered intensity variation caused by off-center locations. Therefore, the scattering cuvette is reliable for differentiation of microemboli type.

Drug-induced subacute cutaneous lupus erythematosus (SCLE) is associated with use of the following classes of medications: anti-hypertensives, anti-cholesterolemia, anti-psychotics, and anti-inflammatory drugs. Docetaxel is an anti-neoplastic agent, which is widely used for treatment of non-small cell lung cancer. Few cases of docetaxel-induced SCLE have been reported in the medical literature. Here, we report the case of a 58-year-old female patient who developed drug-induced SCLE after administration of docetaxel. After 4 cycles of chemotherapy with docetaxel and cisplatin, erythematous skin eruptions developed on the patient's face. Skin biopsies of the eruptions were remarkable for interfacing dermatitis with basement membrane thickening. Immunofluorescent study revealed characteristic features of SCLE, including granular deposition of IgM, C3, and apoptotic bodies along the basement membrane. The skin eruptions resolved gradually after cessation of drug and with the use of topical corticosteroids.

✓ Total removal is reported of a parasagittal meningioma that invaded the lateral wall and lateral recess of the posterior third of the superior sagittal sinus. The operation was performed by using a silicone rubber non-collapsible tube with an inflatable balloon cuff at each end for the bypass of the sinus blood, and entailed repair of the defect in the sinus wall by a saphenous vein graft. The clinical results and angiographic findings are presented.