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Background: A dosimeter with high spatial and temporal resolution would be of significant interest for pencil beam scanning (PBS) proton beams' characterization, especially when facing small fields and beams with high temporal dynamics. Optical imaging of scintillators has potential in providing sub‐millimeter spatial resolution with pulse‐by‐pulse basis temporal resolution when the imaging system is capable of operating in synchrony with the beam‐producing accelerator. Purpose: We demonstrate the feasibility of imaging PBS proton beams as they pass through a plastic scintillator detector to simultaneously obtain multiple beam parameters, including proton range, pencil beam's widths at different depths, spot's size, and spot's position on a pulse‐by‐pulse basis with sub‐millimeter resolution. Materials and methods: A PBS synchrocyclotron was used for proton irradiation. A BC‐408 plastic scintillator block with 30 × 30 × 5 cm3 size, and another block with 30 × 30 × 0.5 cm3 size, positioned in an optically sealed housing, were used sequentially to measure the proton range, and spot size/location, respectively. A high‐speed complementary metal‐oxide‐semiconductor (CMOS) camera system synchronized with the accelerator's pulses through a gating module was used for imaging. Scintillation images, captured with the camera directly facing the 5‐cm‐thick scintillator, were corrected for background (BG), and ionization quenching of the scintillator to obtain the proton range. Spots' position and size were obtained from scintillation images of the 0.5‐cm‐thick scintillator when a 45° mirror was used to reflect the scintillation light toward the camera. Results: Scintillation images with 0.16 mm/pixel resolution corresponding to all proton pulses were captured. Pulse‐by‐pulse analysis showed that variations of the range, spots' position, and size were within ± 0.2% standard deviation of their average values. The absolute ranges were within ± 1 mm of their expected values. The average spot‐positions were mostly within ± 0.8 mm and spots' sigma agreed within 0.2 mm of the expected values. Conclusion: Scintillation‐imaging PBS beams with high‐spatiotemporal resolution is feasible and may help in efficient and cost‐effective acceptance testing and commissioning of existing and even emerging technologies such as FLASH, grid, mini‐beams, and so forth. [ABSTRACT FROM AUTHOR]

Design of flexible porous materials where the diffusion of guest molecules is regulated by the dynamics of contracted pore aperture is challenging. Here, a flexible porous self‐assembly consisting of 1D channels with dynamic bottleneck gates is reported. The dynamic pendant naphthimidazolylmethyl moieties at the channel necks provide kinetic gate function, that enables unusual adsorption for light hydrocarbons. The adsorption for CO2 is mainly dominated by thermodynamics with the uptakes decreasing with increasing temperature, whereas the adsorptions for larger hydrocarbons are controlled by both thermodynamics and kinetics resulting in an uptake maximum at a temperature threshold. Such an unusual adsorption enables temperature‐dependent separation of CO2 from the corresponding hydrocarbons. [ABSTRACT FROM AUTHOR]

The rise of artificial intelligence and the Internet of Things have spurred an increasing demand for wearable, sustainable, and maintenance‐free power sources. Organic thermoelectric (OTE) devices are emerged as promising candidates because they are capable of converting heat energy into electricity directly without the need of moving parts, capable of flexible and seamless integration with multifunctional miniaturized electronics. In addition, OTE devices can perform straightforward as various self‐powered sensors, boosting their applications in the field of intelligent interactions. This review focuses on recent advances in OTE materials and devices for applications in energy harvesting and sensing. The basic knowledge and key parameters of OTE materials and devices are presented, followed by detailed introduction of recent progress of OTE generators, sensors, and other OTE‐integrated devices. Next, several aspects of optimizing OTE devices toward multifunctional applications are highlighted. Finally, an overview of the current challenges and future research directions of OTE‐based devices is addressed. It is hoped that this review can pave the way for speeding up a bright future for the development and practical applications of OTE devices. [ABSTRACT FROM AUTHOR]

Acute gastroenteritis outbreaks may be caused by the excretion of norovirus (NoV) from asymptomatic individuals. Despite numerous studies involving asymptomatic NoV infection during outbreaks in China, a comprehensive assessment of its role has not been conducted, which is critical for emergency management. Our objective was to assess the prevalence of asymptomatic NoV infection during outbreaks in China. We conducted a comprehensive search of multiple databases, including PubMed, Web of Science, Cochrane Library, China National Knowledge Infrastructure, China Wanfang, and China Weipu, between January 1, 1997 and June 19, 2023. The retrieved articles and their references underwent screening, which utilized polymerase chain reaction‐based assays for the detection of NoV in asymptomatic individuals during outbreaks that occurred in China. The primary summary data were the prevalence of asymptomatic NoV infection in outbreaks. We generated pooled estimates of asymptomatic prevalence in the population as a whole and in subgroups by using random‐effect models. Of the 97 articles included, the pooled asymptomatic prevalence of NoV among 5117 individuals in outbreaks was 17.6% (95% confidence interval [CI]: 14.1–21.3). The asymptomatic prevalence of NoV GII (17.1%, 95% CI: 12.9–21.5) was similar to that of NoV GI (22.0%, 95% CI: 12.8–32.4). However, the proportion of asymptomatic individuals involved in NoV GII (57.44%) was significantly higher than that of NoV GI (5.12%), and NoV GII (75.26%) was reported much more frequently than NoV GI (14.43%) in the included articles. Meta‐regression analysis of 11 possible influencing factors (geographic region, setting, season, sample type, genotype, transmission route, occupation, age, per capita income, study quality, and cases definition) showed that the source of heterogeneity might be related to the outbreak settings, per capita income, and study quality (p = 0.037, 0.058, and 0.026, respectively). Of particular note was the asymptomatic prevalence peaked in preschoolers (27.8%), afterward, it fell into trough in elementary and junior school children (10.5%), before the second peak located in adults (17.8%), and the elderly (25.2%). Prevalent genotypes reported include GII.4, followed by GII.17, GII.2, GII.3, GII.6, and so forth. The estimated asymptomatic prevalence of NoV during outbreaks in China was as high as 17.6%, with NoV GII dominating. In addition, genetic subtypes of NoV in outbreaks should be detected whenever possible. The role of asymptomatic individuals in NoV outbreaks cannot be ignored. This knowledge will help governments develop public health policies and emergency response strategies for outbreaks, assess the burden, and develop vaccines. [ABSTRACT FROM AUTHOR]

SUMMARY: Plant A/T‐rich protein and zinc‐binding protein (PLATZ) transcription factors play important roles in plant growth, development and abiotic stress responses. However, how PLATZ influences plant drought tolerance remains poorly understood. The present study showed that PLATZ4 increased drought tolerance in Arabidopsis thaliana by causing stomatal closure. Transcriptional profiling analysis revealed that PLATZ4 affected the expression of a set of genes involved in water and ion transport, antioxidant metabolism, small peptides and abscisic acid (ABA) signaling. Among these genes, the direct binding of PLATZ4 to the A/T‐rich sequences in the plasma membrane intrinsic protein 2;8 (PIP2;8) promoter was identified. PIP2;8 consistently reduced drought tolerance in Arabidopsis through inhibiting stomatal closure. PIP2;8 was localized in the plasma membrane, exhibited water channel activity in Xenopus laevis oocytes and acted epistatically to PLATZ4 in regulating the drought stress response in Arabidopsis. PLATZ4 increased ABA sensitivity through upregulating the expression of ABSCISIC ACID INSENSITIVE 3 (ABI3), ABI4 and ABI5. The transcripts of PLATZ4 were induced to high levels in vegetative seedlings under drought and ABA treatments within 6 and 3 h, respectively. Collectively, these findings reveal that PLATZ4 positively influences plant drought tolerance through regulating the expression of PIP2;8 and genes involved in ABA signaling. Significance Statement: PLATZs have been demonstrated to play important roles in plant growth, development and responses to environmental stimuli, but how they affect drought stress remain unknown. For these purposes, we reveal that PLATZ4 increases drought tolerance by regulating the expression of PIP2;8 and genes involved in ion transport, antioxidant metabolism, small peptides and abscisic acid signaling. We also reveal the aquaporin activity of PIP2;8 and its roles in regulating drought stress. These findings extend the current view about the regulatory mechanism of PLATZs and the function of PIP2;8. [ABSTRACT FROM AUTHOR]

Most unsymmetric quadrilateral elements have demonstrated a high tolerance to mesh distortion in pure bending problems involving coarse meshes. However, they have difficulty achieving acceptable results in shearing‐dominated problems, and the element's performance is affected by the degree of mesh distortion. In this paper, two 8‐node quadrilateral elements are developed by introducing two different incompatible modes into the unsymmetric formulation. The unsymmetric framework with two different sets of interpolation functions for displacement fields provides the basis for the immunity property. The incompatible displacement mode and the enhanced assumed strain guarantee the completeness of the displacement field interpolation polynomials, and the satisfaction of L2$$ {L}_2 $$‐orthogonality condition ensures the accuracy of the simulations. The resulting elements, respectively, denoted as UQ10 and UQ10/E4, can provide exact solutions for both pure and linear bending problems and exhibit excellent insensitivity in shear‐dominated tests. Furthermore, they are invariant, rapidly converging, and free of various locking problems. [ABSTRACT FROM AUTHOR]

Treatment tolerability is a significant limitation to pancreatic cancer treatment with radiotherapy due to proximity to highly radiosensitive organs and respiratory motion necessitating expanded target margins. Further, pancreatic tumors are difficult to visualize on conventional radiotherapy systems. Surrogates are often used to locate the tumor but are often inconsistent and do not provide strong positional relations throughout the respiratory cycle. This work utilizes a retrospective dataset of 45 pancreatic cancer patients treated on an MR‐Linac system with cine MRI acquired for real‐time target tracking. We investigated intra‐fraction motion of tumors and two abdominal surrogates, leading to prediction models between the tumor and surrogate. Patient specific motion evaluation and prediction models were generated from 225 cine MRI series acquired during treatment. Tumor contours were used to evaluate the pancreatic tumor motion. Linear regression and principal component analysis (PCA) based models were used to predict tumor position from the anterior‐posterior (AP) motion of the abdominal surface, the superior‐inferior (SI) motion of the diaphragm, or a combination. Models were evaluated using mean squared error (MSE) and mean absolute error (MAE). Contour analysis showed the average pancreatic tumor motion range was 7.4 ± 2.7 mm and 14.9 ± 5.8 mm in the AP and SI directions, respectively. The PCA model had MSE of 1.4 mm2 and 0.6 mm2, for the SI and AP directions, respectively, with both surrogates as inputs for the models. When only the abdomen surrogate was used, MSE was 1.3 mm2 and 0.4 mm2 in the SI and AP directions, while it was 0.4 mm2 and 1.3 mm2 when only the diaphragm surrogate was used. We evaluated intra‐fraction pancreatic tumor motion and demonstrated prediction models between the tumor and surrogate. The models calculated the pancreatic tumor position from diaphragm, abdominal, or both contours within standard pancreatic cancer target margin, and the process could be applied to other disease sites in the abdominothoracic cavity. [ABSTRACT FROM AUTHOR]

Radiation protection safety and wear comfort of personal protective equipment (PPE) are of vital importance to nuclear personnel involved. Unfortunately, it is difficult for current PEE to meet the increasing requirements, which causes tremendous threats to health and reduced working efficiency. Here, a highly filled polymer fiber for textile‐based PPE to deal with the dilemma is put forward. PbWO4 (PWO) particles are superficially modified with styrene maleic anhydride (SMA) and then titanate coupling agent (bis(dioctyl pyrophosphate) ethylene titanate (BPET)) to form PWO@SMA‐BPET. After that, as high as 70 wt% PWO@SMA‐BPET/polyvinyl alcohol (PVA) fibers are obtained by solution blending and wet spinning in succession. Synergistic effects of surface modification with SMA and BPET lead to uniform dispersion PWO particles and good compatibility of interfaces in highly filled fibers. Importantly 36.6% γ‐ray (105 keV) shielding has been detected at three‐layer fabrics with 70 wt% PWO@SMA‐BPET/PVA fiber. Besides, the fabrics also display 116 mm s−1 of air permeability and 5388 g m−2 24 h of water vapor permeability, respectively. This work discloses synergistic effects on surface modification of high loading inorganic particles in polymer fibers, which give a further boost to γ‐ray shielding safety and wear comfort of PPE. [ABSTRACT FROM AUTHOR]

As a derivative of GeTe and MnTe, GeMnTe2 exhibits a cubic structure with no phase transition. Compared to GeTe, it is considerably cheaper and has a significantly high carrier concentration compared to MnTe, making it an excellent thermoelectric (TE) material with promising applications. Herein, a charge‐balanced vacancy engineering strategy is employed, resulting in a significant improvement in the power factor of GeMnTe2. Furthermore, the density functional theory calculation shows that the doping of Bi and the absence of Ge synergically increase the density of states near the Fermi level. Power factors of ≈13.7 μW cm−1 K−2 are achieved at 8% Bi content, a 22% improvement compared to the undoped system, while a final maximum ZT value of about 1.12 and an average ZT value of 0.72 are achieved. This indicates that charge‐balance vacancy engineering is an effective optimization method for the GeMnTe2 system, which can effectively improve the TE performance. [ABSTRACT FROM AUTHOR]

Purpose: Since 4D‐MRI is inadequate to capture dynamic respiratory variations, real‐time cinematographic (cine) MRI is actively used in MR‐guided radiotherapy (MRgRT) for tumor motion evaluation, delineation, and tracking. However, most radiotherapy imaging platforms do not support the format of cine MRI from clinical MRI systems. This study developed an institutional solution of clinical cine MRI for tumor motion evaluation in radiotherapy applications. Methods: Cine MRI manipulation software (called Cine Viewer) was developed within a commercial Treatment Planning System (TPS). It consists of (1) single/orthogonal viewers, (2) display controllers, (3) measurement grids/markers, and (4) manual contouring tools. Results: The institutional solution of clinical cine MRI incorporated with radiotherapy application was assessed through case presentations (liver cancer). Cine Viewer loaded cine MRIs from 1.5T Philips Ingenia MRI, handling MRI DICOM format. The measurement grids and markers were used to quantify the displacement of anatomical structures in addition to the tumor. The contouring tool was utilized to localize the tumor and surrogates on the designated frame. The stacks of the contours were exhibited to present the ranges of tumor and surrogate motions. For example, the stacks of the tumor contours from case‐1 were used to determine the ranges of tumor motions (∼8.17 mm on the x‐direction [AP‐direction] and ∼14 mm on the y‐direction [SI‐direction]). In addition, the patterns of the displacement of the contours over frames were analyzed and reported using in‐house software. In the case‐1 review, the tumor was displaced from +146.0 mm on the x‐direction and +125.0 mm on the y‐direction from the ROI of the abdominal surface. Conclusion: We demonstrated the institutional solution of clinical cine MRI in radiotherapy. The proposed tools can streamline the utilization of cine MRI for tumor motion evaluation using Eclipse for treatment planning. [ABSTRACT FROM AUTHOR]

The unsymmetric finite element is based on the virtual work principle with different sets of test and trial functions. In this article, the incompatible four‐node quadrilateral element and eight‐node hexahedral element originated by Wilson et al. are extended to their unsymmetric forms. The isoparametric shape functions together with Wilson's incompatible functions are chosen as the test functions, while internal nodes at the middle of element sides/edges are added to generate the trial functions with quadratic completeness in the Cartesian coordinate system. A local area/volume coordinate frame is established so that the trial shape functions can be explicitly obtained. The key idea which avoids the matrix inversion is that the trial nodal shape functions are constructed by standard quadratic triangular/tetrahedral elements and then transformed in consistent with the quadrilateral/hexahedral elements. Numerical examples show that the present elements keep the merits of both incompatible and unsymmetric elements, that is, high numerical accuracy, insensitivity to mesh distortion, free of trapezoidal and volumetric locking, and easy implementation. [ABSTRACT FROM AUTHOR]

Purpose: Ethos adaptive radiotherapy (ART) is emerging with AI‐enhanced adaptive planning and high‐quality cone‐beam computed tomography (CBCT). Although a respiratory motion management solution is critical for reducing motion artifacts on abdominothoracic CBCT and improving tumor motion control during beam delivery, our institutional Ethos system has not incorporated a commercial solution. Here we developed an institutional visually guided respiratory motion management system to coach patients in regular breathing or breath hold during intrafractional CBCT scans and beam delivery with Ethos ART. Methods: The institutional visual‐guidance respiratory motion management system has three components: (1) a respiratory motion detection system, (2) an in‐room display system, and (3) a respiratory motion trace management software. Each component has been developed and implemented in the clinical Ethos ART workflow. The applicability of the solution was demonstrated in installation, routine QA, and clinical workflow. Results: An air pressure sensor has been utilized to detect patient respiratory motion in real time. Either a commercial or in‐house software handled respiratory motion trace display, collection and visualization for operators, and visual guidance for patients. An extended screen and a projector on an adjustable stand were installed as the in‐room visual guidance solution for the closed‐bore ring gantry medical linear accelerator utilized by Ethos. Consistent respiratory motion traces and organ positions on intrafractional CBCTs demonstrated the clinical suitability of the proposed solution in Ethos ART. Conclusion: The study demonstrated the utilization of an institutional visually guided respiratory motion management system for Ethos ART. The proposed solution can be easily applied for Ethos ART and adapted for use with any closed bore‐type system, such as computed tomography and magnetic resonance imaging, through incorporation with appropriate respiratory motion sensors. [ABSTRACT FROM AUTHOR]

As the photoanode material of photoelectrochemical (PEC) cells, hematite (Fe2O3) is a very promising candidate. Herein, the nanocoral‐like hematite film is designed using a simple hydrothermal method. The conductivity of the material improves by Ti ion doping, and a thin ZnFe2O4 film is deposited on the surface to form the type‐II heterostructure, which regulates the transport path of the carriers. At the same time, the FeOOH catalyst accelerates the oxygen evolution kinetics on the electrode surface. Finally, the photocurrent density of the TiFe2O3/ZnFe2O4/FeOOH photoanode reaches 1.93 mA cm−2 at 1.23 VRHE, and the open voltage is negatively shifted by 200 mV, compared with the Fe2O3 photoanode, down to 0.62 V. This work proves that element doping and surface modification improve the PEC performance by optimizing the transport path of carriers and increasing the reaction rate of oxygen evolution reaction. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this work is to create a decision support methodology to predict when patients undergoing radiotherapy treatment for locally advanced lung cancer would potentially benefit from adaptive radiotherapy. The proposed methodology seeks to eliminate the manual subjective review by developing an automated statistical learning model to predict when tumor regression would trigger implementation of adaptive radiotherapy based on quantified anatomic changes observed in individual patients on‐treatment cone beam computed tomographies (CTs). This proposed process seeks to improve the efficacy and efficiency of both the existing manual and automated adaptive review processes for locally advanced stage III lung cancer. Methods: A predictive algorithm was developed as a decision support tool to determine the potential utility of mid‐treatment adaptive radiotherapy based on anatomic changes observed on 1158 daily CBCT images across 43 patients. The anatomic changes on each axial slice within specified regions‐of‐interest were quantified into a single value utilizing imaging similarity criteria comparing the daily CBCT to the initial simulation CT. The range of the quantified metrics for each fraction across all axial slices are reduced to specified quantiles, which are used as the predictive input to train a logistic regression algorithm. A "ground‐truth" of the need for adaptive radiotherapy based on tumor regression was evaluated systematically on each of the daily CBCTs and used as the classifier in the logistic regression algorithm. Accuracy of the predictive model was assessed utilizing both a tenfold cross validation and an independent validation dataset, with the sensitivity, specificity, and fractional accuracy compared to the ground‐truth. Results: The sensitivity and specificity for the individual daily fractions ranged from 87.9%–94.3% and 91.9%‐98.6% for a probability threshold of 0.2–0.5, respectively. The corresponding average treatment fraction difference between the model predictions and assessed ART "ground‐truth" ranged from −2.25 to −0.07 fractions, with the model predictions consistently predicting the potential need for ART earlier in the treatment course. By initially utilizing a lower probability threshold, the higher sensitivity minimizes the chance of false negative by alerting the clinician to review a higher number of questionable cases. Conclusions: The proposed methodology accurately predicted the first fraction at which individual patients may benefit from ART based on quantified anatomic changes observed in the on‐treatment volumetric imaging. The generalizability of the proposed method has potential to expand to additional modes of adaptive radiotherapy for lung cancer patients with observed underlying anatomic changes. [ABSTRACT FROM AUTHOR]

Liquid‐liquid phase separation has been recognized as an approach to realize cellular compartmentalization and create subdivisions of intracellular space into functional membraneless organelles. Multiphase coacervate droplets with complex, nested inner phases as a generic phenomenon are known to be involved in significant biochemical processes and facilitate specific functions. Herein, we present a strategy to develop molecular self‐sorting complexation that leads to the formation of lipid‐rich sub‐compartments in membraneless coacervate microdroplets. We also show the specific localization and visualization of hydrophobic lipid domains within multiphase hydrophilic droplets under a fluorescence microscope by developing a rationally synthesized aggregation‐induced emission (AIE)‐active molecule. The AIE probe with a tetraphenylethylene core and four water‐soluble glucosamine units exhibits high sensitivity and selectivity towards the lipid‐rich microdomains. We anticipate that the design of fluorescently localized self‐sorting liquid droplets will shed light on the research of mimicking multicompartalized organelles and help to understand dynamic reorganization of sub‐divided space in protocell systems. [ABSTRACT FROM AUTHOR]

One biosynthetic gene cluster (BGC) usually governs the biosynthesis of a series of compounds exhibiting either the same or similar molecular scaffolds. Reported here is a multiplex activation strategy to awaken a cryptic BGC associated with tetracycline polyketides, resulting in the discovery of compounds having different core structures. By constitutively expressing a positive regulator gene in tandem mode, a single BGC directed the biosynthesis of eight aromatic polyketides with two types of frameworks, two pentacyclic isomers and six glycosylated tetracyclines. The proposed biosynthetic pathway, based on systematic gene inactivation and identification of intermediates, employs two sets of tailoring enzymes with a branching point from the same intermediate. These findings not only provide new insights into the role of tailoring enzymes in the diversification of polyketides, but also highlight a reliable strategy for genome mining of natural products. [ABSTRACT FROM AUTHOR]

With the increase of wind power penetration in the power system, wind farm (WF) needs to limit active power and accurately track the instructions from the dispatch centre. Since a WF has many distributed wind turbines (WTs), it is a crucial issue to reasonably distribute power reference values to WTs. In this study, a novel active power dispatch (APD) strategy based on dynamic grouping of WTs is proposed. This strategy considers the characteristics and operating conditions of WTs, which can smoothen the power reference values to WTs and reduce fluctuations of key parameters of WTs. Then, a distributed dispatch strategy based on multi‐agent system consistency algorithm (MASCA) is applied for APD, which provides a dispatch strategy for WTs that does not require a centralised control centre. And the segmental virtual consistency algorithm is presented as an improvement of MASCA, which innovatively allows MASCA to support the grouping strategy for APD. Finally, the simulations show that the proposed strategy can enable WTs to obtain smoother reference power to track the dispatching instruction while reducing fluctuations of rotor speed and pitch angle, which is helpful to alleviate the fatigue of WTs. The dispatch strategy also shows good robustness when some communication is interrupted. [ABSTRACT FROM AUTHOR]

Abstract: Efficient ways are presented to accomplish photonic controlled‐phase‐flip gate and entangler with the assistance of imperfect double‐sided quantum‐dot‐microcavity systems, but without ancillary qubits. Compact quantum circuits for implementing entanglement swapping between photon pairs and electron pairs are then designed. Unity fidelities of the schemes can be achieved, and physical imperfections in the construction processes are detected by single‐photon detectors. Also, the efficiencies of the schemes can be further improved by repeating the operation processes when the undesired performances are detected. The evaluations show that the schemes are possible with current experiment parameters. [ABSTRACT FROM AUTHOR]

Transgenic crops are increasingly promoted for their practical effects on suppressing certain insect pests, but all transgenic crops are not equally successful. The insect pests can easily develop resistance against single Bacillus thuringiensis (Bt) toxin transgenic crops. Therefore, transgenic crops including two or more mixed Bt-toxins can solve this problem by delaying the resistance development and killing the majority of targeted pests before the evolution of resistance. It is important to test the controlling effects of transgenic crops including multiple mixed toxins on a particular insect pest. Previous research has checked the cross-resistance and interactions between Bt toxins Cry1Ac and Cry2Ab against one susceptible and four resistant strains of cotton bollworm. The results showed that independence was the main interaction type between two toxins for the susceptible strain, whereas synergism was the main interaction type for any one resistant strain. However, the optimal combinations of two toxins were not obtained. In the present study, we developed two multi-exponential equations (namely bi- and tri-exponential equations) to describe the combination effects of two Bt toxins. Importantly, the equations can provide predictions of combination effects of different continuous concentrations of two toxins. We compared these two multi-exponential equations with the generalized linear model (GLM) in describing the combination effects, and found that the bi- and tri-exponential equations are better than GLM. Moreover, the bi-exponential equation can also provide the optimal dose combinations for two toxins. [ABSTRACT FROM AUTHOR]

Objectives: To investigate clinical and sonographic features of subcutaneous angioleiomyoma with histopathologic correlation. Methods: Clinical features of 141 cases and sonographic appearances of 33 cases of histopathologically proven subcutaneous angioleiomyoma were retrospectively reviewed. Clinical information included patient age, sex, tumor location, and symptoms. Sonographic features included tumor size, location, contour, margin, component, echogenicity, calcifications, and vascularity. Sonograms were analyzed with histopathologic correlation by a single radiologist and a single pathologist. Results: Clinical features of the 141 cases of angioleiomyoma included the following: 78.0% of the cases (110 of 141) were on the lower leg or ankle; 55.3% of the patients (78 of 141) had pain at the tumor location; the female‐to‐male ratio was 1.61:1.00, and most cases occurred in patients in the third through sixth decades. Sonographic features of the 33 cases of angioleiomyoma included the following: 85.0% of the cases (28 of 33) were smaller than 20 mm; 94.0% to 97.0% were solid, oval, parallel to the skin, well defined, and homogeneously hypoechoic and without calcifications; 75.8% (25 of 33) were superficially located, close to or in contact with the dermis; and 39.4% (13 of 33) showed low or moderate internal vascularity. Conclusions: Typical clinical and sonographic features of angioleiomyoma may include a female patient with a painful lower leg or ankle subcutaneous mass, a superficial location, especially in contact with the dermis, a small size (<20 mm), an oval shape, a parallel orientation to the skin, well‐defined margins, complete solid components, homogeneous hypoechogenicity, low or moderate vascular density, and absence of calcifications. [ABSTRACT FROM AUTHOR]

Background Given the parallel entry of working instruments through a single incision in laparoendoscopic single-site surgery, loss of triangulation in the abdominal cavity and counteracting movements of the instruments are inevitable obstacles. Some specially designed devices have emerged to ameliorate these challenges. Methods Twenty-four novice participants were randomized into four groups using assigned instruments, conventional straight instruments, single-curved instruments, double-curved instruments and articulating instruments, respectively, to perform two basic tasks (peg transferring and pattern cutting) 14 times in a modified simulator. A test of the tasks and a resection of the intestine segment of a rat were performed. The task scores and evaluation of intraoperative skills during the resection of the intestine segment were recorded. The instrument of modified National Aeronautics and Space Administration Task Load Index (NASA-TLX) was completed. Results The task scores of the groups using single-curved instruments and articulating instruments were better than the other two groups on the simulator tasks, consistent with the evaluation of intraoperative skills during the resection of intestine segment. As the proficiency with the instruments increased, the task scores improved, as demonstrated by the learning curve. The workload measured by the modified NASA-TLX tool demonstrated that the groups using articulating instruments and double-curved instruments had a heavier workload in most of the categories compared with the other two groups. Conclusions Single-curved and articulating instruments are more effective than conventional straight and double-curved devices, and are favourable in laparoendoscopic single-site surgery for novice learners. [ABSTRACT FROM AUTHOR]

A Cu2O-mediated cross coupling of arenediazonium tetrafluoroborates with trimethylsilyl cyanide to form aromatic nitriles is presented. This protocol tolerates a wide range of functional groups and gives good to excellent yields under mild conditions. Cu2O provides appealing and convenient access to aromatic nitriles compared with the traditional Sandmeyer reaction with toxic CuCN via nucleophilic substitution under relatively harsh conditions. [ABSTRACT FROM AUTHOR]