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The aim of this study was to assess the diagnostic yield and outcomes of intraoperative enteroscopy (IOE) in patients with overt small bowel bleeding in the era of balloon‐assisted enteroscopy and capsule endoscopy. We retrospectively reviewed the medical records of patients with small bowel bleeding who underwent IOE from January 2005 to April 2016 in a tertiary medical center. A total of 18 patients with overt small bowel bleeding who underwent a total 18 IOE procedures were included. The mean amount of blood transfusion was 35.7 units (SD, 21.4 units), and 11 patients had hypovolemic shock. The diagnostic yield of the IOE procedures was 94.4% (17/18). The most common pathologic diagnosis was ulcer. The rebleeding rate was 44.4% (8/18), and the overall survival rate was 61.1% (11/18). IOE remains a valuable tool for diagnosing overt small bowel bleeding. The usage of IOE might potentially be limited due to critical clinical conditions in the era of deep enteroscopy. A specific caution should be taken in performing IOE due to the high morbidity of the procedure.

The prevalence and incidence of Crohn's disease (CD) in Asia is rising, and it is important to know the risk factors of mortality. In our study, CD patients diagnosed and treated in the Chang Gung Memorial Hospital Linkou branch were enrolled from January 1989 to October 2019. The collected data included age, sex, disease duration, location and behavior of the disease, biochemical parameters at admission, medication history, surgical history, and comorbidities. The mean age at diagnosis was 35.7 ± 16.1 years old and the male‐to‐female ratio was 2.4. The penetrating type of CD was the most common (41.3%) of disease behavior. The ileocolonic area is the most common location of disease involvement (79%). 7.7% of patients had low serum albumin levels (<3 g/dL). 16.8% of patients had hemoglobin levels less than 10 g/dL. Of the patients included, 4 died during the follow‐up period. Low serum albumin levels at admission (p= .0307) are an independent predictor for mortality. In conclusion, it is important in perioperative care, especially for CD patients with hypoalbuminemia.

The construction of quaternary carbon centers via C–C coupling protocols remains challenging. The coupling of tertiary C(sp3) with secondary or tertiary C(sp3) counterparts has been hindered by pronounced steric clashes and many side reactions. Herein, we have successfully developed a type of bisphosphine ligand iron complex-catalyzed coupling reactions of tertiary alkyl halides with secondary alkyl zinc reagents and efficiently realized the coupling reaction between tertiary C(sp3) and secondary C(sp3) with high selectivity for the initial instance, which provided an efficient method for the construction of quaternary carbon centers with high steric hindrance. The combination of an iron catalyst and directing group of the substrate makes the great challenging transformation possible.

On January 1, 2024, a devastating M7.6 earthquake struck the Noto Peninsula, Ishikawa Prefecture, Japan, resulting in significant casualties and property damage. Utilizing information from the first six days after the earthquake, this article analyzes the seismic source characteristics, disaster situation, and emergency response of this earthquake. The results show: 1) The earthquake rupture was of the thrust type, with aftershock distribution showing a north-east-oriented belt-like feature of 150 km. 2) Global Navigation Satellite System (GNSS) and Interferometric synthetic aperture radar (InSAR), observations detected significant westward to north-westward co-seismic displacement near the epicenter, with the maximum horizontal displacement reaching 1.2 m and the vertical uplift displacement reaching 4 m. A two-segment fault inversion model fits the observational data well. 3) Near the epicenter, large Peak Ground Velocity (PGV) and Peak Ground Acceleration (PGA) were observed, with the maxima reaching 145 cm/s and 2681 gal, respectively, and the intensity reached the highest level 7 on the Japanese (Japan Meteorological Agency, JMA) intensity standard, which is higher than level 10 of the United States Geological Survey (USGS) Modified Mercalli Intensity (MMI) standard. 4) The observation of the very rare multiple strong pulse-like ground motion (PLGM) waveform poses a topic worthy of research in the field of earthquake engineering. 5) As of January 7, the earthquake had left 128 deaths and 560 injuries in Ishikawa Prefecture, with 1305 buildings completely or partially destroyed, and had triggered a chain of disasters including tsunamis, fires, slope failures, and road damage. Finally, this paper summarizes the emergency rescue, information dissemination, and other disaster response and management measures taken in response to this earthquake. This work provides a reference case for carrying out effective responses, and offers lessons for handling similar events in the future.

In this article, an artificial intelligence (AI) approach is proposed for the prediction of scattered far fields by 3-D perfect-electrical-conducting (PEC) targets. The conventional computational electromagnetic (CEM) methods are plagued by at least two issues. One is the mesh generation, and the other is the intensive or time-consuming solution of matrix equations which could be unbearable. Machine-learning (ML) methods provide a new perspective to tackle the problems by skipping the two steps. Point clouds can well describe the geometrical information of a radar target. Directly using the point cloud rather than the created mesh with the point data should be workable, so we will take the point cloud as the input of the neural network (NN). As for the output, we will let the NN extract a kind of inherent feature parameters (IFPs) that are distinctive to each target and independent of incident and scattering directions. The characteristic mode theory (CMT) is employed to acquire the IFPs for the generation of datasets. The scattered far-field can be readily computed using the IFPs when the incident and scattering directions are specified. We call the NN constructed to realize the function Electromagnetic PointNet (EMPN). Numerical examples show that the EMPN can achieve remarkable reductions in CPU time and even memory requirements. The proposed approach is convenient to run from the input of a point cloud file that may be obtained by using a cellphone with a depth camera to the output of scattered far-field or radar cross section (RCS).

Vedolizumab has a good safety profile for the treatment of inflammatory bowel disease. Agranulocytosis is a rare but fatal condition. Although many drugs are considered to have a high risk of agranulocytosis, no previous study has mentioned vedolizumab. A 71‐year‐old female with Sjogren's syndrome received vedolizumab treatment for moderate to severe ulcerative colitis. Her symptoms improved; however, leukopenia was noted after the first dose. Four days after the second dose, she complained of oral and chest pain. Agranulocytosis, oral candidiasis, and Epstein‐Barr virus esophagitis with ulceration were noted. After granulocyte‐colony stimulating factor treatment, the white blood cell count returned to normal and the esophageal ulcers healed. Vedolizumab is a very safe gut‐selective biologic agent, but it also carries the risk of agranulocytosis.

Hepatocellular carcinoma (HCC) represents one of the most prevalent and lethal type of malignancies around the globe. Despite the advancement in medical research and therapeutics development, HCC still remains a taunting challenge in clinical settings. Recent studies indicate that the presence of cancer stem cells (CSCs) may be the underlying factor for treatment failure, distant metastasis, and disease recurrence. Elevated stemness gene expression has been correlated to disease stage and poorer prognosis in HCC patients. Initially, we established that β‐catenin is highly expressed in HCC clinical samples. We subsequently re‐validated the idea that CD133+/CD90+ subpopulation cells exhibited CSCs properties including elevated stemness expression (β‐catenin, Nanog, c‐Myc, and Twist1), increased self‐renewal capacity and metastatic potential. Using this cell model, we tested the potential anti‐CSCs effects of phenethyl isothiocynanate (PEITC), a phytochemical isolated from cruciferous vegetables. Treatment of PEITC led to a decreased percentage of CD133+/CD90+ cells in both Huh7 and Sk‐Hep1 cell lines. In addition, PEITC suppressed stemness gene expression, self‐renewal ability, and metastatic potential in HCC CSCs. Mechanistically, PEITC conveyed its anti‐CSCs effects via upregulating microRNA‐214, a negative regulator of β‐catenin. In conclusion, we provided evidence that PEITC could suppress HCC CSCs generation/maintenance. With further clinical testing, PEITC could be used either alone or in combination with currently available chemotherapeutic agents to achieve improved efficacy.

Endobronchial ultrasound bronchoscopy (EBUS) and needle confocal laser endomicroscopy (nCLE) are techniques for screening benign and malignant lesions of the hilar and mediastinal lymph node (HMLN). This study investigated the diagnostic potential of EBUS, nCLE, and combined EBUS and nCLE in HMLN lesions. We recruited 107 patients with HMLN lesions who were examined by EBUS and nCLE. A pathological examination was performed, and the diagnostic potential of EBUS, nCLE, and combined EBUS‐nCLE approach was analyzed according to the results. Among the 107 cases of HMLN lesions, 43 cases were benign and 64 cases were malignant on pathological examination, 41 cases were benign and 66 cases were malignant on EBUS examination; 42 cases were benign and 65 cases were malignant on nCLE examination; 43 cases were benign and 64 cases were malignant on combined EBUS‐nCLE examination. The combination approach had 93.8% sensitivity, 90.7% specificity, and 0.922 area under the curve, which was higher than those of EBUS (84.4%, 72.1%, and 0.782, respectively) and nCLE diagnosis (90.6%, 83.7%, and 0.872, respectively). The combination approach had a higher positive predictive value (0.908), negative predictive value (0.881), and positive likelihood ratio (10.09) than that of EBUS (0.813, 0.721, and 3.03, respectively) and nCLE (0.892, 0.857, and 5.56, respectively), whereas, the negative likelihood ratio was lower than that for EBUS (0.22) and nCLE (0.11). No serious complications occurred in patients with HMLN lesions. To summarize, the diagnostic efficacy of nCLE was better than EBUS. The EBUS‐nCLE combination is a suitable approach for diagnosing HMLN lesions.

In this letter, a four-beam circularly polarized (CP) antenna in the Ku-band based on metasurface (MS) is proposed. It consists of a defected polarization conversion metasurface (PCM) and a feeding structure. The PCM is composed of centrosymmetric units, each of which contains a pair of square patches and a pair of L-shaped patches. When it is placed above the feeding structure, the linearly polarized (LP) wave is converted into a CP wave, and the gain is also enhanced. Furthermore, through loading stubs on the microstrip feeding lines and modifying the PCM as a defected PCM by removing some units from the MS, both the back and sidelobe levels are reduced. The realized antenna has a compact dimension of 1.05λ0 × 1.05λ0 × 0.12λ0. It has a −10 dB impedance bandwidth from 12.69 to 13.38 GHz (5.3%) and a 3 dB axial ratio bandwidth from 12.69 to 13.88 GHz (9.1%). When the four ports are excited, the four beams point at (θ, φ) = (40°, 105°), (40°, 165°), (40°, 285°), and (40°, 345°), respectively. The four beam directions may be altered by readjusting the coupling slots in the ground plane. The gain in the working band reaches 8.27 dBi.

In this letter, a machine learning method is presented to evaluate the scattering by 2-D conducting objects. First, the scattered far field is expressed by angular harmonics with weighted wave coefficients (WCs), which are distinctive to the cross-section of the scatterer. Then, a neural network (NN) is trained to learn the WCs from a range of objects. Finally, the NN is used to extract the WCs for a given object, and the scattered far field or radar cross-section is readily computed by using the WCs. Numerical examples show that the proposed approach can be a viable choice for fast online prediction.

In this communication, an artificial intelligent method based on the prevailing multihead attention mechanism for prediction of scattering properties of 2-D targets is presented. To make the predicting approach independent of the incident direction of an excitation plane wave, a kind of inherent feature parameters (IFPs) for a specific target is defined and applied as the output of the artificial neural network (ANN). Two types of targets are experimented, one of which is composed of polygons and the other of smooth shapes. Numerical results show that the proposed method has satisfactory prediction accuracy and computing speed, as well as good generalization ability.

Graph Neural Networks (GNNs) aim to extend deep learning techniques to graph data and have achieved significant progress in graph analysis tasks (e.g., node classification) in recent years. However, similar to other deep neural networks like Convolutional Neural Networks (CNNs) and Recurrent Neural Networks (RNNs), GNNs behave like a black box with their details hidden from model developers and users. It is therefore difficult to diagnose possible errors of GNNs. Despite many visual analytics studies being done on CNNs and RNNs, little research has addressed the challenges for GNNs. This paper fills the research gap with an interactive visual analysis tool, GNNLens, to assist model developers and users in understanding and analyzing GNNs. Specifically, Parallel Sets View and Projection View enable users to quickly identify and validate error patterns in the set of wrong predictions; Graph View and Feature Matrix View offer a detailed analysis of individual nodes to assist users in forming hypotheses about the error patterns. Since GNNs jointly model the graph structure and the node features, we reveal the relative influences of the two types of information by comparing the predictions of three models: GNN, Multi-Layer Perceptron (MLP), and GNN Without Using Features (GNNWUF). Two case studies and interviews with domain experts demonstrate the effectiveness of GNNLens in facilitating the understanding of GNN models and their errors.

The flow maldistribution inside plate-fin heat exchangers is a decisive factor leading to the deterioration of heat transfer performance. This article proposes the configurations of flat and curved baffles with different holes to optimize flow distribution. The invasive method using fiber Bragg grating (FBG) sensors for monitoring the local flow velocity in heat exchangers is first proposed. Multiple FBG sensors are embedded in the plate-fin core to measure the flow velocity of each channel. The effectiveness in balancing the flow velocity of flat and curved baffle configurations is compared against a header configuration without a baffle. The results indicate that adding a baffle, whether it is flat or curved, is profitable to facilitate the flow field inside the plate-fin core. Compared with no baffle configuration, the flat and curved baffle configurations achieve a decrease rate of 61% and 66% in the sum flow nonuniformity of heat exchangers. The standard deviation has been reduced by 60% and 80%, respectively. The energy loss caused by the curved plate configuration is relatively low. The embedded FBG sensors address real-time monitoring of local flow velocity in the plate-fin heat exchanger. The ameliorative baffle structure in the header and FBG sensing technology provide ideas for optimizing and monitoring the internal flow field inside plate-fin heat exchangers.

This article is concerned with developing a viable procedure to evaluate the scattering property of a satellite object. First, to deal with the uncertainty of attitudes of the object with respect to the direction of incidence, the characteristic mode theory is exploited, which is independent of the incident waves. The total scattered field is obtained by summing up the individual characteristic scattered fields with modal weighting coefficients. Second, the ionosphere Faraday effect that may significantly change the polarization behaviors is considered when the frequency is at L-band or below for a ground-based identifying radar. The ionosphere is taken as a sparse and weakly magnetized plasma, and the approximate Wentzel–Kramers–Brillouin method is adopted to calculate the propagations of two intrinsic modes through the ionosphere. The Stokes vector is assumed to be the measured quantities, and the Mueller matrix is employed to fully describe the polarized scattering process.

In this study, elastoplastic model for the surrounding rock of axisymmetric circular tunnel is investigated under three-dimensional (3D) principal stress states. Novel numerical solutions for strain-softening surrounding rock were first proposed based on the modified 3D Hoek–Brown criterion and the associated flow rule. Under a 3D axisymmetric coordinate system, the distributions for stresses and displacement can be effectively determined on the basis of the redeveloped stress increment approach. The modified 3D Hoek–Brown strength criterion is also embedded into finite element software to characterize the yielding state of surrounding rock based on the modified yield surface and stress renewal algorithm. The Euler implicit constitutive integral algorithm and the consistent tangent stiffness matrix are reconstructed in terms of the 3D Hoek–Brown strength criterion. Therefore, the numerical solutions and finite element method (FEM) models for the deep buried tunnel under 3D principal stress condition are presented, so that the stability analysis of surrounding rock can be conducted in a direct and convenient way. The reliability of the proposed solutions was verified by comparison of the principal stresses obtained by the developed numerical approach and FEM model. From a practical point of view, the proposed approach can also be applied for the determination of ground response curve of the tunnel, which shows a satisfying accuracy compared with the measuring data.

In this article, isosorbide divalerate (SDV), an alternative renewable resource plasticizer for degradable poly(butylene succinate) (PBS) was successfully synthesized with isosorbide and valeric acid, and was characterized by Fourier transform infrared (FTIR). The mechanical properties, glass transition temperature (Tg), crystallization properties, rheological behavior of PBS/SDV blends was studied in detail. The results showed that incorporation of SDV had successfully reduced Tgof the PBS composites, particularly at 20 wt% SDV, where the value of Tgexhibited a reduction of 12 °C or 39% compared to pure PBS, demonstrating SDV possessed plasticizing efficacy. The crystallinity of PBS was declined by presence of SDV in the blends, and the incorporation of 20 wt% SDV into PBS matrix promoted an impressive decrease of exceeding 22%. Significant enhancement of the toughness and flexibility of PBS was achieved by the addition of SDV. The rheological test revealed that the decrease of modulus and viscosity improved the processing properties of the materials, which broadened the PBS applications. Altogether the SEM showed the fracture surface of the composites undergoes a brittle-tough transition with increasing SDV content below 12% content, meanwhile, significant phase separation was observed in the composites with high content of SDV.

• We carry out in situ SR-XRD experiments and magnetic measurements of CrCoNi MEA, CrFeCoNi and CrMnFeCoNi HEAs to investigate their lattice distortion and magnetic property evolutions with temperature from 293 to 123 K and 293 to 5 K, respectively. • We observe linear lattice contraction and a general reduction of local lattice distortion, and its variation tendency is in well agreement with the reported temperature dependency of stacking fault energy (SFE). • It is striking to find a paramagnetic to ferromagnetic transformation of CrFeCoNi HEA at cryogenic temperature, suggesting it as a promising candidate for soft magnetic materials. • Our findings suggest reductions of lattice distortion with temperature possibly making a critical contribution to twinning at low temperature. • Magnetic measurements demonstrated none obvious correlation between magnetizations of the three alloys and their deformation behaviors. Deformation mechanisms and magnetic properties of medium and high entropy alloys (MEA/HEAs) closely relate to lattice distortion and are strongly temperature-dependent, in particular, at low temperature ranges. However, little attention has been paid to the evolution of lattice distortion with temperature decreasing and its effects on deformation behavior and magnetic state transition. In this work, we carry out in situ synchrotron radiation based X-ray powder diffraction (SR-XRD) experiments from 293 to 123 K aiming for determining lattice distortion evolutions of CrCoNi MEA, CrFeCoNi and CrMnFeCoNi HEAs. Magnetic measurements at corresponding low temperatures and cryogenic ranges are further conducted. The in situ SR-XRD results demonstrate a general reduction of lattice distortion magnitude with temperature decreasing, which shows a similar tendency with that of reported stacking fault energy (SFE) values. It is thus suggested that lattice distortion reduction possibly makes a critical contribution to deformation mechanism transition. The magnetic measurement results show a clear ferromagnetic transition of CrFeCoNi HEA when temperature is below 173 K. While, no obvious magnetic state transition is observed for CrCoNi MEA and CrMnFeCoNi HEA. The present findings on lattice distortion evolutions will pave the way for designing targeted HEAs with particular properties. [ABSTRACT FROM AUTHOR]

This study investigated the antimicrobial resistance of isolates from patients with refractory Helicobacter pylori. The resistance rate was 34.1% for amoxicillin, 92.7% for clarithromycin, 65.9% for metronidazole, 85.4% for levofloxacin, and 29.3% for rifabutin. Dual resistance to both clarithromycin and levofloxacin was found in 73.2%. The antimicrobial resistance rate of refractory H. pyloriwas extremely high, which had become a major consideration in therapeutic challenge.

Introduction: Pleural fluid adenosine deaminase (pfADA) is a simple, rapid and inexpensive surrogate marker for tuberculous pleural effusion (TPE). A nationwide cut-off of 40 U/L is currently used based on overseas data. There is a need to optimise the diagnostic utility of pfADA by establishing a local cut-off value. In this study, we aimed to describe the demographics and clinical characteristics of patients with TPE and non-TPE; determine the sensitivity and specificity of current pfADA of 40 U/L; and establish a new local pfADA cut-off for TPE.Methods: We conducted a single-centre, observational, prospective study of patients with exudative pleural effusion and pfADA measured from 1 October 2019 to 30 April 2020 at Queen Elizabeth Hospital, Malaysia.Results: The diagnosis of analysed patients (n= 93) included TPE (n= 41), malignancy (n= 28), parapneumonic effusion (n= 12) and other causes (n= 12). The mean pfADA was 51.15 U/L (standard deviation (SD) = 13.77) among TPE group and 18.86 U/L (SD = 12.33) among non-TPE. When analysis was restricted to TPE patients, the local pfADA cut-off is 29.6 U/L, with a sensitivity of 97.6% and specificity of 90.4%. The current pfADA of 40 U/L has a sensitivity of 87.8% and specificity of 92.3%.Conclusion: We established a local pfADA cut-off of 29.6 U/L for TPE. Optimising the utility of pfADA helps to enhance clinicians’ treatment confidence of TPE when initial work-up is inconclusive.

There has been a surge of emphasis on polarimetric imaging modalities recently, in which Mueller matrix polarimetry (MMP) is at the heart of our understanding of polarization properties of an imaged sample. However, the historiography of MMP, predominantly undertaken in optics, largely lost sight of the potential of terahertz radiation on interactions with the imaged samples, especially biological ones. In addition, studies of MMP are generally concerned with intensity-only measurements requiring at least 16 polarization combinations, which dramatically add to the time cost in the process of measurements. The proposed study sets out to examine the complete 4 × 4 MMP from 0.2 to 1 THz using only orthogonal polarizations for two-dimensional (2-D) and 3-D imaging on leaf. A modified THz time domain spectrometer with self-designed linear polarizers is utilized for measurements and data acquisition. The Mueller matrix polar decomposition and Mueller matrix transform are employed to facilitate extraction of polarization characteristics of the imaged leaf. The time-of-flight technique is adopted to assist in the 3-D reconstruction of the leaf. The results demonstrate the effectiveness and feasibility of the novel measurement synthesis approach and the modified system for accurate characterization of the sample. Meanwhile, the findings indicate that MMP is superior in feature extraction as well as contrast enhancement of the sample. The insights gained from this article may be of assistance to the characterization of biological samples with MMP at higher frequencies for future research.

Iridium (Ir) could potentially improve ethanol electro-oxidation to CO2, employing CO species (COad) to be the key C1 intermediates. Thus, it is essential to carry out the investigation on CO adsorption and oxidation on the Ir surface. With regard to CO adsorption, in situattenuated total reflection surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS) shows that only linearly adsorbed COadspecies (COL) are detected at ca. 2010–2060 cm–1. With a continuous dosing of CO, the open-circuit potential (OCP) of the Ir electrode decreases to ca. 600 mV, being associated with the displacement and/or consumption of surface OHadspecies. For CO oxidation, the onset oxidation potential is at ca. 0.64 and 0.55 V versusreversible hydrogen electrode in acidic and alkaline media, respectively. Meanwhile, the Stark tuning rates of ca. 29 ± 1 cm–1V–1(acidic media) and 34 ± 1 cm–1V–1(alkaline media) suggest an approximate COLmonolayer (especially in acidic media), and a stable COL–H2Ofreeco-structure could be formed. Therefore, CO oxidation might start from the edges and/or defect sites of the COL–H2Ofreeco-structure, following the “nucleation and growth” kinetic model of the Langmuir–Hinshelwood mechanism. This work may provide new insights into understanding CO adsorption and oxidation on the Ir electrode surface.

This paper presents a novel optical type in‐cell fingerprint sensor (iFP) technology, which can detect a user's fingerprint on display. By using low temperature polysilicon (LTPS) TFT process, new sensor material, and active pixel sensor circuit (APS), this sensor can detect a fingerprint image with good performance. The FPS/Touch/Display Driver IC (FTDI) is also implemented in this work, and successfully demonstrated.

The order Acipenseriformes, which includes sturgeons and paddlefishes, represents “living fossils” with complex genomes that are good models for understanding whole-genome duplication (WGD) and ploidy evolution in fishes. Here, we sequenced and assembled the first high-quality chromosome-level genome for the complex octoploid Acipenser sinensis(Chinese sturgeon), a critically endangered species that also represents a poorly understood ploidy group in Acipenseriformes. Our results show that A. sinensisis a complex autooctoploid species containing four kinds of octovalents (8n), a hexavalent (6n), two tetravalents (4n), and a divalent (2n). An analysis taking into account delayed rediploidization reveals that the octoploid genome composition of Chinese sturgeon results from two rounds of homologous WGDs, and further provides insights into the timing of its ploidy evolution. This study provides the first octoploid genome resource of Acipenseriformes for understanding ploidy compositions and evolutionary trajectories of polyploid fishes.

Multicomponent reactions hold the potential to maximize the synthetic efficiency in the preparation of diverse and complex molecular scaffolds. An unprecedented formal [3+1+1+1] annulation approach for the one-step synthesis of fluoroalkylated 2-H-pyrimidines commencing from perfluoroalkyl alkenes, paraformaldehyde, and ammonium carbonate is described. By harnessing readily accessible (CH2O)nand cheap (NH4)2CO3as a formamidine surrogate, this method effectively replaces traditionally preformed amidines with a pyrimidine assembly. The multicomponent reaction proceeds in a step-economical, operationally simple, metal-free, and additive-free manner, featuring a broad substrate scope, excellent functional group compatibility, and scalability. The potential for the synthetic elaboration of the obtained 2-H-pyrimidine is further demonstrated in the alkylation and vinylation of its C2 position.

A three-component strategy was developed to enable hydrodefluoroamination of β-trifluoromethyl enones by selectively activating two C(sp3)-F bonds in the trifluoromethyl group. The method involved a sequence of carbonyl reduction, hydrodefluorination, and defluoroamination under transition-metal-free conditions. Synthetically useful (E)-stereospecific α-fluoroenamides were obtained in good yields with diverse functional group tolerance, which could be easily transformed into valuable organofluorides and heterocycles. The carbonyl auxiliary exerts both electronic and steric impacts on the CF3-alkenes, allowing for controllable and selective defluorination.

Carbenes, recognized as potent intermediates, enable unique chemical transformations, and organoborons are pivotal in diverse chemical applications. As a hybrid of carbene and the boryl group, α-boryl carbenes are promising intermediates for the construction of organoborons; unfortunately, such carbenes are hard to access and have low structural diversity with their asymmetric transformations largely uncharted. In this research, we utilized boryl cyclopropenes as precursors for the swift synthesis of α-boryl metal carbenes, a powerful category of intermediates for chiral organoboron synthesis. These α-boryl carbenes undergo a series of highly enantioselective transfer reactions, including B–H and Si–H insertion, cyclopropanation, and cyclopropanation/Cope rearrangement, catalyzed by a singular chiral copper complex. This approach opens paths to previously unattainable but easily transformable chiral organoborons, expanding both carbene and organoboron chemistry.

Overactivated microglia and persistent neuroinflammation hold an important role in the pathophysiology of neurodegenerative diseases. The extract of Lycoris chejuensis(CJ) and its active compound, 7-deoxy-trans-dihydronarciclasine (named E144), attenuated expressions of pro-inflammatory factors, including nitric oxide, prostaglandin E2, inducible nitric oxide synthase, cyclooxygenase-2 (COX-2), tumor necrosis factor α (TNF-α), and interleukin 6, secreted by lipopolysaccharide-activated BV-2 microglial cells, as measured by an enzyme-linked immunosorbent assay or western blotting. In contrast, CJ extract and E144 promoted the secretion of the anti-inflammatory cytokine, interleukin 10. Moreover, we found that E144 attenuated the expression of TNF-α and COX-2 in the cerebral cortex of lipopolysaccharide-treated mice and/or T2576 transgenic mice as well as reduced the reactive immune cells visualized by ionized calcium-binding adaptor molecule 1. Our results suggest the possibility of E144 to serve as a potential anti-neuroinflammatory agent by preventing excess production of pro-inflammatory factors.

Abstract: To investigate lattice distortion evolutions of CrCoNi medium-entropy alloy (MEA), CrFeCoNi, and CrMnFeCoNi high-entropy alloys (HEAs) with temperature increasing from 300 to 1323 K, we conduct in situ synchrotron-radiation-based X-ray diffraction experiments. Electron backscattering diffraction, energy-dispersive X-ray spectroscopy and X-ray absorption near edge fine structure spectra (XANES) are further carried out to uncover variations of microstructure, morphology and oxidation resistance. Generally, the lattice will expand continuously with temperature increasing, however, the expansion rate is affected by grain growth and oxidation. The oxidation resistance of CrCoNi MEA is slightly higher than CrFeCoNi HEA, and much higher than CrMnFeCoNi HEA. The XANES spectra demonstrate higher oxidation resistance of Ni, Co, and Fe than Cr and Mn. Formation of local short-range order structures around Ni and Co is observed, but no such features are observed around Fe and Mn. The present findings are significant on deepening the understandings of correlations between atomic structure and mechanical properties in advanced HEAs. Graphic Abstract:

We have developed a protocol for insertion of alkylidene carbenes into the B–H bonds of amine–borane adducts, enabling, for the first time, the construction of C(sp2)–B bonds by means of carbene-insertion reactions. Various acyclic and cyclic alkenyl borane–amine adducts were prepared from readily accessible starting materials in good to high yields and were subsequently subjected to a diverse array of functional group transformations. The unprecedented spiro B–N heterocycles prepared in this study have potential utility as building blocks for the synthesis of pharmaceuticals. Preliminary mechanistic studies suggest that insertion of the alkylidene carbenes into the B–H bonds of the amine–borane adducts proceeds via a concerted process involving a three-membered-ring transition state.

Severe gastrointestinal (GI) hemorrhage is a rare initial presentation in Crohn's disease (CD) and poses a therapeutic challenge for clinical care. Currently, there is no conclusive consensus or guideline on the treatment modalities for CD‐related GI bleeding. We present the case of a 21‐year‐old man with acute lower GI bleeding who accepted transcatheter arterial embolization to attain hemostasis. After 1 day of embolization, intractable abdominal pain happened and emergent laparoscopic exploration was arranged. Operation finding reported stenosis and chronic inflammation changes near ileal‐cecal valve. Besides, several bleeding sites and perforation are detected, which is different from splanchnic branch of embolization. Pathology of resected bowel reported transmural acute and chronic inflammation with fibrin and purulent exudates is shown on the serosa. CD is favored. In CD, the most common bleeding site in the literature is located at descending and sigmoid colon. To attain hemostasis, some literature studies raise concerns about embolic‐related complication of intestinal infarction. We would like to share a case of unusual bleeding site and provide consideration of embolization as an option for the treatment of CD.

Catalytic asymmetric reactions in which water is a substrate are rare. Enantioselective transition-metal-catalyzed insertion of carbenes into the O–H bond of water can be used to incorporate water into the stereogenic center, but the reported chiral catalysts give good results only when α-aryl-α-diazoesters are used as the carbene precursors. Herein we report the first highly enantioselective O–H bond insertion reactions between water and α-alkyl- and α-alkenyl-α-diazoesters as carbene precursors, with catalysis by a combination of achiral dirhodium complexes and chiral phosphoric acids or chiral phosphoramides. Participation of the phosphoric acids or phosphoramides in the carbene transfer reaction markedly suppressed competing side reactions, such as β-H migration, carbene dimerization, and olefin isomerization, and thus ensured good yields of the desired products. Fine-tuning of the ester moiety facilitated enantiocontrol of the proton transfer reactions of the enol intermediates and resulted in excellent enantioselectivity. This protocol represents an efficient new method for preparation of multifunctionalized chiral α-alkyl and α-alkenyl hydroxyl esters, which readily undergo various transformations and can thus be used for the synthesis of bioactive compounds. Mechanistic studies revealed that the phosphoric acids and phosphoramides promoted highly enantioselective [1,2]- and [1,3]-proton transfer reactions of the enol intermediates. Maximization of molecular orbital overlap in the transition states of the proton transfer reactions was the original driving force to involve the proton shuttle catalysts in this process.

Endoscopic mucosal resection (EMR) is an established technique for treating large colonic polyps. However, en bloc resection of large sessile lesions using conventional EMR is technically challenging and can generally be performed only in a piecemeal manner, resulting in low radical resection rates and high recurrence rates. Endoscopic submucosal dissection (ESD), a more difficult and time‐consuming technique, is an alternative procedure with high en bloc resection rates and low recurrence rates. Therefore, we present a novel technique: tip‐in EMR. We evaluated the feasibility and safety of tip‐in EMR for the en bloc resection of large sessile colorectal polyps or laterally spreading tumors (LSTs). In this retrospective observational study, we included patients who underwent tip‐in EMR for the removal of large colonic polyps (>10 mm) at Shuang Ho Hospital over a 2‐year period (September 2015 to September 2017). Clinical variables, including age, gender, polyp size and morphology, procedure time, complications, and pathology, were analyzed. A total of 46 polyps were removed from 42 adult patients through tip‐in EMR. The patients' mean ± SD age was 61.0 ± 12.0 years. The polyps were located in the right‐side colon, transverse colon, left‐side colon, and rectum in 39.1%, 17.4%, 37.0%, and 6.5% of the patients, respectively. The mean polyp size was 20.4 ± 5.6 mm (range = 10‐35 mm). LSTs were the predominant polyp type (n = 37, 81.5%). Among all LSTs (n = 37), 12 lesions were of granular type, and 25 lesions were nongranular. All polyps were removed en bloc using tip‐in EMR. The mean procedure time was 14.9 ± 8.8 min. Immediate bleeding occurred in only one patient (2.2%). No patient developed perforation or delayed bleeding. Regarding histopathological findings, 9 polyps (19.6%) were sessile serrated adenomas, 16 (34.8%) were tubular adenomas, 12 (26.1%) were tubulovillous adenomas, and 1 (2.2%) was a villous adenoma. High‐grade dysplasia was observed in four polyps (8.7%), and one lesion was an in situ carcinoma. Surveillance colonoscopy was performed in 20 patients (47.6%) over a mean follow‐up period of 12.7 ± 5.3 months. Among these patients, only one patient exhibited local recurrence. Tip‐in EMR is a novel alternative technique for polyp resection that is proven to be relatively safe and efficient for the en bloc removal of large sessile colonic polyps.

The aim of the study is to evaluate the diagnostic yield and risks of screening colonoscopy in octogenarians and older. A retrospective review of medical records in the Chang Gung Healthcare Center from January 2010 to December 2016 was performed. A total of 164 adults older than 80 years receiving screening colonoscopy were enrolled. Cecal intubation rate, colonoscopic finding, renal function, colon preparation, and procedure‐related complications were used to estimate the outcome of colonoscopy. All participants were under deep sedation. The crude cecal intubation rate was 95%. Acceptable colon preparation was 95.1%. No procedure‐related complications, such as bleeding or perforation, occurred in this study. The level of creatinine increasing more than 25% were two (6.3%) in polyethylene glycol group and 10 (16.1%) in oral sodium phosphate solution (NaP) group. The colonoscopic finding were as follows: 19 advanced neoplasms (11.5%), 56 non‐advanced adenomas (34.1%), and 38 hyperplastic polyps (23.2%). This study disclosed the diagnostic yield and safety of colonoscopy in octogenarians and older. In addition, we should be cautious when giving NaP to these subjects.

Mueller matrix imaging, as one of the polarimetric imaging modalities, is an effective tool to achieve imaging enhancement as well as explore fine details of the imaged sample at microwave and optical frequencies. However, little work has been reported at terahertz (THz) frequencies, which could provide an exclusive insight in exploring fine details of biological specimens for their sensitivity to THz absorption due to their various water contents. This article presents a 0.3-THz polarimetric system for Mueller matrix imaging measurements both in reflection and transmission modes. Two experiments are designed to demonstrate the capability of Mueller matrix theory and its polar decomposition in imaging enhancement and properties characterization. The structural similarity index (SSIM) is employed to serve as the metric for image quality assessment, by which the performance of the Mueller matrix imaging is evaluated. The SSIM values of the Mueller matrix could reach as high as 0.9-0.98 for the leaf sample and 0.9 for the indium tin oxide (ITO) target, respectively, whereas that of the raw polarization images could only stabilize at 0.7-0.9 and 0.2-0.4. Furthermore, the SSIM value of the decomposition parameters for the ITO target could reach nearly 1, the maximum value. The imaging results both in visual and analytical perspectives demonstrate successful system integration at THz band. The work paves the way for our exploration of biomedical imaging of tissues and cells at higher THz frequencies in the immediate future.