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The Pummerer reaction represents a well-known transformation of sulfoxides. Mechanistically, this reaction is initiated by the generation of the thionium ion, whereas forming such intermediates typically requires the use of a stoichiometric amount of activating reagent. In this regard, we report the activator-free Pummerer-type transformation, a silver-catalyzed thio-Claisen rearrangement of aryl sulfoxides with AIBN. Facilitated by silver catalyst, AIBN is transformed into highly reactive ketenimine in situ, which directly captures the sulfoxides to generate thionium ion intermediates.

This study examines a multiple-priority emergency evacuation optimization problem with time-dependent demand uncertainty. A multiple-priority dynamic traffic model—namely, the multiple-priority cell transmission model (MPCTM) —is developed to simulate the priority of network flows for emergency evacuation response. Moreover, a robust optimization approach is applied to formulate such an emergency evacuation response problem. The robust counterpart solutions of the proposed uncertainty model have been shown to be tractable, using the duality theorem. Finally, a real example of Ya’an earthquake emergency evacuation planning verifies the effectiveness of the proposed MPCTM.

Convolution-based methods are increasingly being used in medical image segmentation tasks and have shown good performance, but there are always problems in segmenting edge parts. These methods all have the following challenges: 1) Previous methods do not highlight the relationship between foreground and background in segmented regions, which is helpful for complex segmentation edges, 2) inductive bias of the convolutional layer leads to the fact that the extracted information is mainly the main part of the segmented area, and cannot effectively perceive complex edge changes and the aggregation of small and many segmented areas,3) different regions around the segmentation edge have different reference values for segmentation, and the ordering of these values is more important when the segmentation task is more complex. To address these challenges, we propose the CM-MLP framework on Multi-scale Feature Interaction (MFI) block and Axial Context Relation Encoder (ACRE) block for accurate segmentation of the edge of medical image. In the MFI block, we propose the Cascade Multi-scale MLP (Cascade MLP) to process all local information from the deeper layers of the network simultaneously, using Squeeze and Excitation in Space(SES) to process and redistribute the weights of all windows in Cascade MLP and utilize a cascade multi-scale mechanism to fuse discrete local information gradually. Then, multiple ACRE blocks cooperate with the deep supervision mechanism to gradually explore the boundary relationship between the foreground and the background, and gradually fine-tune the edges of the medical image. The segmentation accuracy (Dice) of our proposed CM-MLP framework reaches 96.98%, 96.67%, and 83.83% on three benchmark datasets: CVC-ClinicDB dataset, sub-Kvasir dataset, and our in-house dataset, respectively, which significantly outperform the state-of-the-art method. The source code and trained models will be available at https://github.com/ProgrammerHyy/CM-MLP.

The fixed-time synchronization and energy consumption of Kuramoto-oscillator networks with multilayer distributed control are studied in this brief. In order to achieve fixed-time synchronization, multilayer networks are designed, including the proportional layer, the finite-time layer and the fixed-time layer. Then, to overcome that Kuramoto-oscillator networks cannot realize synchronization at the desired time, the sufficient conditions for Kuramoto-oscillator networks are proposed to guarantee the fixed-time synchronization. To achieve energy saving of the controller, the supremum of energy consumption is obtained when the Kuramoto-oscillator networks reach synchronization. Finally, an example for Kuramoto-oscillator networks is given to illustrate the effectiveness of the proposed synchronization and energy consumption.

Multidimensional Floquet-driven alignment systems with dynamical symmetry present various exotic phenomena and applications. However, there are challenges in directly characterizing large-spin dynamical symmetry from spectra. Here, we first observe the symmetry-protected selection rules of dynamical high-dimensional parity in a large-spin (F= 4) system. We theoretically construct a Floquet-driven alignment system that can be used to reveal high-dimensional spatiotemporal symmetry. In the experiment, the system is implemented in Cs atomic gas subjected to two-dimensional Floquet-modulated magnetic resonance driving. By developing Floquet detection protocols of alignment double-sided spectra, we directly verify symmetry-protected selection rules of dynamical high-dimensional parity for large-spin systems. This work advances the exploration of dynamical symmetry to large spins, and unravels a universal Floquet scheme for the investigation of symmetry-protected selection rules.

Purpose: To investigate the clinical characteristics, endocrinological function, and etiology of bilateral adrenal lesions in hospitalized patients. Methods: A retrospective study of 777 patients with bilateral adrenal lesions was conducted at the Chinese People’s Liberation Army General Hospital between January 2013 and January 2018. Patients’ demographic features, hormonal profiles, imaging findings, and histopathological findings were reviewed from database records. Results: Of the 777 patients with bilateral adrenal lesions, 495 were men. The mean age at diagnosis was 52.0 ± 13.0 years. Overall, 511 (65.8%) cases were benign, followed by adrenal metastases (n= 224, 28.8%), pheochromocytoma (n= 26, 3.3%), adrenal lymphoma (n= 9, 1.2%), and adrenal corticocarcinoma (ACC; n= 7, 0.9%). Hormonal evaluation revealed that 34.3% of bilateral adrenal lesions were functional. The primary etiologies of functional lesions were primary aldosteronism (16.6%, 129/777), and primary bilateral macronodular adrenocortical hyperplasia (PBMAH; 8.8%, 68/777). Patients with lymphoma and metastases were significantly older than those with benign nonfunctional lesions (60.4 ± 11.0 years vs. 54.5 ± 10.4 years and 57.9 ± 10.8 years vs. 54.5 ± 10.4 years, respectively; both P< 0.001). Lesions in patients with adrenal lymphoma, ACC, pheochromocytoma, metastases, congenital adrenal hyperplasia, tuberculosis, and Cushing’s syndrome were significantly larger than benign nonfunctional lesions (all P< 0.001). Conclusion: Benign adrenal lesions and metastases from the lungs are the most common causes of bilateral adrenal lesions. Primary aldosteronism and PBMAH are the most prevalent functional lesions. Moreover, patients with lymphoma or metastases are older and their masses are larger.

The asymmetric construction of allylic C–O bonds with primary or secondary aliphatic alcohols remains a substantial challenge in Pd-catalyzed allylation chemistry. Here, we report the development of an additive-free, palladium-catalyzed asymmetric aminomethylative etherification of conjugated dienes that enables the efficient, asymmetric O-allylation of primary and secondary aliphatic alcohols as well as water. Mechanism studies revealed that the hydrogen-bonding interaction between the alcohol and the in situintroduced aminomethyl moiety is critical to facilitate the nucleophilic addition of the alcohol to the π-allylpalladium species, which opened up the possibility of using aliphatic alcohols and water as nucleophilic substrates. This reaction tolerates a broad range of functional groups and shows remarkable regioselectivities and uniformly high enantioselectivities, which provides a direct and rapid approach to optically pure allylic 1,3-amino ethers and 1,3-amino alcohols from simple starting materials.

With the concern of the environment, green dry cutting technology is getting more and more attention and self-lubricating tool technology plays an important role in dry cutting. Due to the demand for high temperature performance of tools during dry cutting process, cemented carbide with Ni3Al as the binder phase has received extensive attention due to its excellent high temperature strength and high temperature oxidation resistance. In this paper, WC-TiC-Ni3Al-CaF2graded self-lubricating material and tools were prepared by microwave heating method, and its microstructure, mechanical properties and cutting performance were studied. Results show that gradient self-lubricating material can be quickly prepared by microwave heating technology, and the strength is equivalent to that of conventional heating technology. CaF2not only plays a role in self-lubrication, but also refines the grain of the material. A reasonable gradient design can improve the mechanical properties of the material. When the gradient distribution exponent is n1= 2, the material has high mechanical properties. Cutting experiments show that the WC-TiC-Ni3Al-CaF2functional gradient self-lubricating tool has better cutting performance than the homogeneous WC-TiC-Ni3Al hard alloys.

Co-substituted LaFeO3was electrodeposited on the surface of BiVO4as a co-catalyst to enhance the water splitting performance. Compared to bare BiVO4, the BiVO4/Co-LaFeO3composite photoanode shows a water oxidation photocurrent of 3.4 mA/cm2at 1.23 V versus reverse hydrogen electrode, accompanied by a notable cathodic shift in the onset potential for 300 mV. Combined optical and electrochemical characterizations show that the solid/electrolyte charge transfer efficiency of BiVO4are dramatically improved by the incorporation of Co-substituted LaFeO3. From the surface kinetic study of charge carriers by intensity-modulated photocurrent spectroscopy, a suppressed surface recombination rate constant is observed and the enhanced photoelectrochemical water splitting performance observed in the BiVO4/Co-LaFeO3photoanode is attributed to the surface passivation effect of Co-substituted LaFeO3.

The surface plasmonic resonance (SPR) effect of Bi can effectively improve the light absorption abilities and photogenerated charge carrier separation rate. In this study, a novel ternary heterojunction of g-C3N4/Bi2MoO6/Bi (CN/BMO/Bi) hollow microsphere was successfully fabricated through solvothermal and in situreduction methods. The results revealed that the optimal ternary 0.4CN/BMO/9Bi photocatalyst exhibited the highest photocatalytic efficiency toward rhodamine B (RhB) degradation with nine times that of pure BMO. The DRS and valence band of the X-ray photoelectron spectroscopy spectrum demonstrate that the band structure of 0.4CN/BMO/9Bi is a z-scheme structure. Quenching experiments also provided solid evidence that the •O2−(at −0.33 eV) is the main species during dye degradation, and the conduction band of g-C3N4is only the reaction site, demonstrating that the transfer of photogenerated charge carriers of g-C3N4/Bi2MoO6/Bi is through an indirect z-scheme structure. Thus, the enhanced photocatalytic performance was mainly ascribed to the synergetic effect of heterojunction structures between g-C3N4and Bi2MoO6and the SPR effect of Bi doping, resulting in better optical absorption ability and a lower combination rate of photogenerated charge carriers. The findings in this work provide insight into the synergism of heterostructures and the SPR absorption ability in wastewater treatment.

We demonstrate a simple technique to lock the frequency of a laser to an atomic transition with a new technique of subnatural linewidth spectroscopy. The coupled rubidium system exhibits an enhanced absorption spectrum of the probe beam with a subnatural linewidth. Compared with other techniques with an additional laser, our scheme only utilizes a single laser, which will be locked. The observed spectroscopic linewidth is down to about 3.5 MHz. The laser frequency fluctuation is about 226 kHz after locking on. The demonstrated scheme offers a convenient and low-cost technique for laser frequency stabilization and related precision measurements.

Oxidative desulfurization (ODS) is a promising method to remove the heterocyclic sulfur compounds from fuel and such process need high-performance catalysts. Polyoxometalates (POMs) have been proven to be excellent catalysts in the ODS reaction, which need to be immobilized on carriers to realize its industrial application. In this work, [β-SiMo3W9O40]n−has been loaded on a sustainable cellulose nanofiber (CNF)-based material, which was then calcined at 400 °C to form an POM-based composite material. CNF was modified by γ-(2,3-epoxypropoxy)propyltrimethoxysilane (GPTMS) and polyethyleneimine (PEI) so that the polyanions and protonated PEI could effectively interact with each other; therefore, POM could be well supported on the carrier. The catalytic results showed that in model oil with the sulfur concentration being 2000 ppm, the removal efficiency of dibenzothiophene, benzothiophene, and 4,6-dimethyldibenzothiophene were 99, 89, and 100%, respectively. In addition, infrared spectra analysis indicated the stability of the catalyst after it was recycled. This work provides a new method to obtain effective heterogeneous ODS catalysts by employing an eco-friendly CNF as raw materials.

Purpose: This paper aims to develop an uncertain global supply chain network design (GSCND) model with rules of origin (RoOs) and limited import quotas, and to discuss the international factors' effects on location decisions. Design/methodology/approach: The authors establish an uncertain GSCND model with the international factors. The transportation costs and customers' demands are characterized as random variables. To deal with the risk of uncertainty, the authors introduce the customers' demand service level. A sample approximation approach (SAA) is used to deal with the service level constraint and turn the proposed model into a mixed integer programming. On the basis of the properties of the proposed model, a hybrid memetic algorithm (MA) is designed to solve it. Findings: The authors find that the proposed MA is efficient to the real supply chain network design problem. Besides, the RoOs and limited import quotas can affect the optimal choices of plant and distribution center locations. Originality/value: The authors propose an uncertain GSCND model with RoOs and limited import quotas. An MA with SAA is designed to solve the proposed model. The authors apply the proposed model into a real global supply chain of an apparel corporation in East Asia, and give some managerial insights. [ABSTRACT FROM AUTHOR]

Herein, a metal-free electrochemical demethoxyl-cyanation of methoxyarenes viaaromatic nucleophilic substitution (SNAr) using TMSCN as a cheap cyanide source under mild conditions has been presented. This transformation utilizes commercially available reagents, cheap electrodes, and simple equipment. Diverse aryl nitriles were successfully obtained in a direct and efficient way with broad substrate scope, excellent functional group tolerance, and selective C−O bond cleavage. Furthermore, late-stage modification of biorelevant compounds and gram-scale synthesis highlighted the potential application of the strategy. Mechanistic investigations suggest that the arene cation radical was considered as the key intermediate for the transformation, and undergoing the followed SNAr process.

Multiple studies have confirmed that acid sphingomyelinase (ASM) activity is associated with depression. The discovery of direct inhibitors against ASM is of great significance for exploring antidepressants and their mechanisms of action. Herein, a series of novel phenylpyrazole analogues were rationally designed and synthesized. Among them, compound 46exhibited potent inhibitory activity (IC50= 0.87 μM) and good drug-like properties. In vivostudies demonstrated that compound 46was involved in multiple antidepressant mechanisms of action, which were associated with a decline of ceramide, including increasing the Bcl-2/Bax ratio and BDNF expression, down-regulating caspase-3 and caspase-9, ameliorating oxidative stress, reducing the levels of proinflammatory cytokines such as TNF-α, IL-1β, and IL-6, and elevating 5-HT levels in the brains of mice, respectively. These meaningful results reveal for the first time that direct inhibitors exhibit remarkable antidepressant effects in the CUMS-induced mouse model through multiple mechanisms of antidepressant action.

Aside from their intended actions, fungicides can drive pest insect outbreaks due to virtually continuous use and pest evolution. Small brown planthopper (SBPH), Laodelphax striatellus, outbreaks occurred recently in many provinces in China, with devastating rice losses. Because exposure to the fungicide jinggangmycin (JGM) increased reproduction of the brown plant hopper, Nilaparvata lugens, via its influence on fatty acid synthase, we posed the hypothesis that JGM and carbendazim (CBM) influence SBPH reproduction via their influence on enzymes involved in other aspects of lipid metabolism. Exposure to the fungicide CBM stimulated SBPH reproduction (egg-laying up by 78%) and to another fungicide, JGM, led to decreased egg-laying (down by 47.3%). These inverse effects are mediated by down-regulated expression of l-3-hydroxyacyl-coenzyme A dehydrogenase (LCHAD) in JGM-treated females and up-regulated expression of hydroxysteroid dehydrogenase-like protein 2-like (HSD) in CBM-treated females. RNAi knockdown of, separately, LCHADand HSDled to reduced egg-laying (down by 52% for dsLCHAD and by 73% for dsHSD). dsLCHAD, dsHSD, and JGM treatments also led to severely reduced ovarian development in experimental SBPH, with shorted and thinned valvula and lack of egg cells in ovaries. Valvula of CBM-treated females enlarged, with banana-shaped eggs in ovaries. These data strongly support our hypothesis.

The increasing attention towards flexible supercapacitors with self-healing ability can be attributed to their capacity to endure deformation and damage. However, the development of self-healing and adhesive hydrogel electrolytes, which serve as substrate materials for supercapacitors, remains a challenge. This work reports an ultrafast gelation method for fabricating multifunctional PAA-SL-CD hydrogels with ultrahigh stretchability, fast self-healing ability, superior adhesion, and high ionic conductivity (6.15 S/m). These excellent properties can be attributed to the hydrogen bonding between β-CD, the catechol groups and PAA chains, as well as metal-catechol coordination, metal-carboxyl coordination, and the unique truncated cone structure of the β-CD molecule. A flexible supercapacitor, fabricated using PAA-SL-CD hydrogel as electrolyte, demonstrates high areal specific capacitance (950 mF/cm2) and a capacitance retention rate of 76.3 % even after five cutting and healing cycles. With the well-designed adhesion of the hydrogel electrolyte, the device exhibits impressive specific capacitance retention after cyclic bending. Notably, a series supercapacitor retains the ability to power a clock for 28 min.

Fe2TiO5was synthesized via the solvothermal method and adopted as co-catalyst to improve the photoelectrochemical (PEC) water splitting performance of BiVO4photoanode. After surface modification by Fe2TiO5, the BiVO4/Fe2TiO5photoanode shows a 300 mV cathodic shift in onset potential and 3 times enhancement in photocurrent, which delivers a photocurrent density of 3.2 mA/cm2at 1.23 V vs reverse hydrogen electrode. Systematic optical, electrochemical, and intensity-modulated photocurrent spectroscopy characterizations were performed to explore the role of Fe2TiO5and reveal that the enhanced PEC performance is mainly caused by the surface passivation effect of Fe2TiO5.

There are large regional variations in the prevalence and mortality of cardiovascular disease in general populations in China. It remains uncertain whether the prevalence in type 2 diabetes mellitus (T2DM) varies by region in China.

A figure measuring interferometer (FMI) method is proposed for high-accuracy measurement of the focal length and distortion of optical systems simultaneously. FMI uses the Zernike coefficients of interference fringe to identify the image point position precisely, and then measures the distance between the image points under the different fields to determine the image height. The field of view can also be accurately obtained by a precise rotating platform. Linear fitting between the field of view and the image height is used to calculate the focal length and distortion. The experimental results indicate that FMI has a relative expanded standard uncertainty of less than 0.01% for focal length and 0.02% for distortion. In brief, the proposed method is feasible for measurement of the focal length and distortion with high accuracy, promising further industrial applications.

One of the central problems in object recognition is to develop appropriate representations for the objects in images. The authors present a novel approach for image representation that is based on graphs. In the proposed image graph, each node represents a patch and edges are added between neighbouring nodes. First, class-specific match-set graphs are generated by matching the image graphs that are in the same categories, and the multi-image matching problem is solved by applying a seed-expansion strategy. Then, the matches between the match-set graphs and an image graph are considered to be the object patches in the image. Finally, the features extracted from these patches are used for the image representation. Extensive experiments are conducted to demonstrate that their approach can obtain state-of-the-art results on several challenging datasets.

County medical alliances (CMAs) in China are considered to be effective in optimizing the layout of medical resources and improving primary healthcare services. To facilitate the implementation of CMAs in multiple geographical clusters, we examine a cluster-based healthcare network design (CHND) problem with patient referral in uncapacitated and capacitated cases. Considering the uncertainty of health demand and unit referral cost, we develop adaptive distributionally robust models for the CHND problem, where the location and allocation decisions anticipate the worst-case expected patient treatment and referral cost over an ambiguity set. In terms of tractability, we reformulate the adaptive distributionally robust models as tractable forms. Further, a hybrid genetic algorithm that combines a genetic algorithm with a commercial solver is designed to improve the computational efficiency for large-scale instances. Finally, we apply our models to a real-world case in Shenzhen, China, to verify the effectiveness of the proposed algorithm and assess the value of the adaptive distributionally robust models over the corresponding robust model. The results show that our algorithm has outstanding efficiency and accuracy when compared to the hybrid particle swarm algorithm and the commercial solver. Moreover, the adaptive distributionally robust model outperforms the robust model in terms of solution quality. [ABSTRACT FROM AUTHOR]

The speckle pattern (line by line) sequential extraction (SPSE) metric is proposed by the one-dimensional speckle intensity level crossing theory. Through the sequential extraction of received speckle information, the speckle metrics for estimating the variation of focusing spot size on a remote diffuse target are obtained. Based on the simulation, we will give some discussions about the SPSE metric range of application under the theoretical conditions, and the aperture size will affect the metric performance of the observation system. The results of the analyses are verified by the experiment. This method is applied to the detection of relative static target (speckled jitter frequency is less than the CCD sampling frequency). The SPSE metric can determine the variation of the focusing spot size over a long distance, moreover, the metric will estimate the spot size under some conditions. Therefore, the monitoring and the feedback of far-field spot will be implemented laser focusing system applications and help the system to optimize the focusing performance.

The initial loss of tension in individual bolts after initial tightening obviously affects the level and the stability of the clamp load in bolted joints. A high-precision instrument to analyze the clamp load loss was developed. In this instrument, an Atlas Copco’s high performance spindle with an accuracy of ±2.5% under the conditions of one million duty cycles was used to tighten the test bolts and nuts. A rotary torque-angle transducer was integrated in the tightening spindle to measure the tightening torque. KMR force washer with a repeatability of < ±1% was applied to monitor the clamping force in real time. Using this instrument, the design of experiment analysis was performed to determine the effect of variables on the initial loss of tension. Those variables included the joint materials, the fastener class, the gasket grade, the lubrication, the surface roughness, the tightening speed, and the number of repeated tightening. The results showed that the tightening speed and the number of repeated tightening had a significant effect on the initial loss of tension. Moreover, a process criterion of eliminating plastic deformation was proposed to minimize the initial loss of tension. The findings presented in this paper will be expected to enhance the reliability and the safety of bolted assemblies, especially in critical applications.

Many studies have examined the influence of global climate change and regional human activities on the climate of arid Central Asia, but their separate contributions have rarely been reported due to lack of a comprehensive description of regional human activities, especially the irrigation process, in the model. In this study, we conducted two sets of 40‐year continuous simulations with and without human activities to distinguish the effects of regional human activities and global climate change on the surface air temperature (T2), humidity (Q2) and precipitation of a typical mountain‐oasis‐desert system in northern Tianshan by using a modified WRF‐Noah model with irrigation processes. The results indicated that the annual average T2, Q2 and convective precipitation during the past 40 years increased by 0.393°C, 0.063 g/kg and 0.014 mm/d, respectively, and the annual average large‐scale precipitation and total annual average precipitation decreased by approximately −0.017 and −0.003 mm/d, respectively. Regional human activities contributed 52.63% and 50.38% of the change in large‐scale precipitation and total precipitation, respectively, while global climate change accounted for more than 80% of the change in temperature and humidity. Among the human activities, irrigation had the largest impact on T2/Q2 over the local irrigation region and on precipitation in the upstream Tianshan mountainous area. However, for the whole region, the increase in the green vegetation fraction was the core factor that impacted the regional climate. Our results can deepen the understanding of the attribution and mechanism of climate change and provide water and heat change references for other mountain‐oasis‐desert systems in arid endorheic regions. We counted the separate contributions of global climate change and regional human activities on the surface air temperature (T2), humidity (Q2) and precipitation of arid Central Asia by difference of two sets of 40‐year continuous simulations with and without human activities. The results indicated that regional human activities contributed 52.63% and 50.38% of the change in large‐scale precipitation and total precipitation, respectively, while global climate change accounted for more than 80% of the change in temperature and humidity. Among the human activities, irrigation had the largest impact on T2/Q2 over the local irrigation region and on precipitation in the upstream Tianshan mountainous area. But the vegetation greening was main reason for the changes of regional climate for the whole region. Our results can deepen the understanding of the attribution and mechanism of climate change and provide water and heat change references for other mountain‐oasis‐desert systems in arid endorheic regions. The attribution and mechanism of regional climate change in a typical mountain‐oasis‐desert system of arid Central Asia were exploredGlobal climate change dominated regional temperature change while regional human activities dominated regional precipitation changeThe increase in the green vegetation fraction was the core factor that impacted regional climate The attribution and mechanism of regional climate change in a typical mountain‐oasis‐desert system of arid Central Asia were explored Global climate change dominated regional temperature change while regional human activities dominated regional precipitation change The increase in the green vegetation fraction was the core factor that impacted regional climate

We study a cavity quantum electrodynamics system in which a cavity mode couples simultaneously with two separate transitions of three-level atoms, and show that three polariton states are created in the coupled cavity-atom system. We report the observation of such polariton states in an experiment with cold Rb atoms confined in a cavity. The experimental results agree with theoretical calculations based on a semiclassical analysis. The three-level cavity-atom system may be used for a variety of fundamental studies and practical applications.

We show that by manipulating quantum interference in a multi-atom cavity quantum electrodynamics (CQED) system, the nonlinear excitation of the cavity-atom polariton can be resonantly enhanced while the linear excitation is suppressed. Under the appropriate conditions, it is possible to selectively enhance or suppress the polariton excitation with two free-pace laser fields. We report on an experiment with cold Rb atoms in an optical cavity and present experimental results that demonstrate such interference control of the CQED excitation and its direct application to studies of all-optical switching and cross-phase modulation of the cavity-transmitted light.

We propose a two-channel cross-phase modulation (XPM) scheme in a multi-atom cavity quantum electrodynamics system consisting of three-level atoms confined in a cavity and coupled by a free-space control laser. A signal laser field is coupled into the cavity, and its transmission through the cavity and reflection from the cavity form two output channels. We show that the free-space control laser induces quantum destructive interference in the normal mode excitation, which can be used to modulate the phase of the output signal light of the reflection channel and the transmission channel. The analytical results and numerical calculations show that large XPM in the coupled cavity–atom system can be realized at low light intensities.

Objective The cortisol concentration in saliva is 10-fold lower than total serum cortisol and accurately reflects the serum concentration, both levels being lowest around midnight. The salivary cortisol assay measures free cortisol and is unaffected by confounding factors. This study analysed published data on the sensitivity and specificity of salivary cortisol levels in the diagnosis of Cushing syndrome.Methods Data from studies on the use of different salivary cortisol assay techniques in the diagnosis of Cushing syndrome, published between 1998 and 2012 and retrieved using Ovid MEDLINE®, were analysed for variance and correlation.Results For the 11 studies analysed, mean sensitivity and specificity of the salivary cortisol assay were both >90%. Repeated measurements were easily made with this assay, enabling improved diagnostic accuracy in comparison with total serum cortisol measurements.Conclusions This analysis confirms the reliability of the saliva cortisol assay as pragmatic tool for the accurate diagnosis of Cushing syndrome. With many countries reporting a rising prevalence of metabolic syndrome, diabetes and obesity – in which there is often a high circulating cortisol level – salivary cortisol measurement will help distinguish these states from Cushing syndrome.

Conventional analytical and numerical methods for the mechanical properties of helical threads are relied on many assumptions and approximations and thus hardly yield satisfied results. A parameterized 3D finite element model of bolted joints with real helical thread geometry is established and meshed with refined hexahedral elements. The Von Mises plasticity criterion, kinematic hardening rule of materials and interfacial contacts are employed to make it possible for the suggested model be able to approach real assembly conditions. Then, the mechanical properties of bolted joints with different thread pitches, thread numbers and modular ratios are investigated, including the contact pressure distribution at joint interfaces, the axial load distribution and stress concentration in screw threads during the loading and unloading process. Simulation results indicate that the load distribution in screw threads produced by the suggested model agrees well the results from CHEN’s photoelastic tests. In addition, an interesting phenomenon is found that tightening the bolt with a large preload first and then adjusting the clamping force by unloading can make the load distribution more uniform and reduce the maximum residual equivalent stress in thread roots by up to 40%. This research provides a simple and practical approach to constructing the 3D finite element model and predicting the mechanical properties of helical thread connection.

In order to ascertain the invasive mechanism and control strategy of the invasive Crofton weed, Ageratina adenophora, its ecological adaptability and population differentiation, the formation of single dominant population, displacement of native plants and sustainable management strategies were investigated. The present results helped to clarify and explain such issues as the adaptability post invasion, interaction and competition between inter- and intra-species and community resistance, thereby providing important references to researches on other invasive alien species.

Abstract: This paper discusses admissibilities of estimators in a class of linear models, which include the following common models: the univariate and multivariate linear models, the growth curve model, the extended growth curve model, the seemingly unrelated regression equations, the variance components model, and so on. It is proved that admissible estimators of functions of the regression coefficient β in the class of linear models with multivariate t error terms, called as Model II, are also ones in the case that error terms have multivariate normal distribution under a strictly convex loss function or a matrix loss function. It is also proved under Model II that the usual estimators of β are admissible for p ⩽ 2 with a quadratic loss function, and are admissible for any p with a matrix loss function, where p is the dimension of β.

Angiopoietin-like protein 4 (Angptl4) is the second member of the angiopoietin-like family of proteins previously shown to increase plasma triglyceride (TG) levels in vivo. We recently reported that Angptl4 is a variable-sized oligomer formed by intermolecular disulfide bonds and undergoes regulated proteolytic processing upon secretion. We now show that adenoviral overexpression of Angptl4 potently increases plasma TG levels by a mechanism independent of food intake or hepatic VLDL secretion. We determined that cysteine residues at positions 76 and 80 of Angptl4, conserved among mouse, rat, and human, are required to form higher order structures. By generating adenoviral expression vectors of Angptl4 containing different epitope tags at both N and C termini, we show that loss of oligomerization results in decreased stability of the N-terminal coiled-coil domain of Angptl4 as well as decreased ability to increase plasma TG levels, suggesting that intermolecular disulfide bond formation plays important roles in determining the magnitude of the hyperlipidemic effect of Angptl4.

This paper presents a novel two-stage distributionally robust optimization model of the two-allocation p-hub median problem with different hub link scales. With the objective of minimizing overall costs of building and operating the hub network, the choices of hub locations and hub link scales are decided in the first stage, while the optimal flows are determined in the second stage once the uncertain demands have been realized. Before establishing the hub network, we just have partial distribution information about the uncertain flow demands, which can be described by a given perturbation set based on the historical information. Due to the ambiguous distributions leading to a computationally intractable model, we reformulate the proposed model into the tractable robust counterpart forms under two types of uncertainty sets (Box+ellipsoidal perturbation set and Generalized ellipsoidal perturbation set). Finally, to demonstrate the effectiveness and applicability for our model, we conduct a case study for the express network system in the Beijing–Tianjin–Hebei region.

The interaction between polychromatic fields and atoms is an important subject in quantum optics. Frequency locking for small frequency interval multi-field is usually required in some experiments. In this letter, we experimentally demonstrate a holistic scheme for bichromatic laser frequency stabilization. Compared with traditional saturation absorption methods and complicated frequency shift schemes, offset locking for bichromatic fields is simply achieved using polarization spectroscopy and Doppler effect. Frequency locking with a wide-range asymmetry of the detuning is also shown. Our scheme makes laser spectroscopy experiments with polychromatic fields more convenient.

A simple method based on Sagnac interferometric spectroscopy (SIS) is applied for frequency stabilization of diode lasers. Sagnac interferometric spectra of rubidium vapor are investigated both theoretically and experimentally. The interference signal at the output of the Sagnac interferometer displays a sharp dispersion feature near the atomic resonance. This dispersion curve is used as the feedback error signal to stabilize the laser frequency. Linewidth of a diode laser is stabilized down to 1 MHz by this modulation-free method.

Objective Autoimmune hypothalamitis (AHT) is a rare inflammatory disorder that involves the hypothalamus. It remains unclear whether autoimmune hypophysitis (AH) and AHT represent different diseases or different aspects of the same disease. Thus, further investigation of AHT is required.Methods A retrospective review of medical and pathological records of AHT patients from the Chinese PLA General Hospital were examined from January 1, 2005 to May 1, 2017. Clinical data, treatments, and outcomes were investigated.Results Five female patients were identified (median age, 42.6 years). Symptoms included central diabetes insipidus, hypopituitarism, hyperprolactinemia, headache, and hypothalamic syndrome. The following hormonal deficits were noted: follicle-stimulating hormone, luteinizing hormone, adrenocorticotropic hormone, thyroid stimulating hormone, and growth hormone. One patient underwent high-dose methylprednisolone pulse treatment (HDMPT) and azathioprine plus intensity modulated radiation therapy (IMRT), and two patients underwent HDMPT and two rounds of replacement therapy. During follow-up, one patient died because of non-compliance with therapy and the others were in remission or they recovered.Conclusions AHT had similar MRI results, pathology, and treatment compared with AH. Thus, it may be a subtype of AH, and AHT patients may also show hypothalamic syndrome.

A DC current sensor based on an optically pumped atomic magnetometer is proposed. It has a high linearity in a wide operation range, since the magnetometer measures the absolute magnitude of the magnetic field produced by the current to be measured. The current sensor exhibits a high accuracy with a non-moment solenoid and magnetic shielding to suppress the influence from the environment. The absolute error of the measured current is below 0.08 mA when the range is from 7.5 mA to 750 mA. The relative error is 5.54 × 10^−5 at 750 mA.

A new method for rectifying image deviation of circular instrument based on perspective transformation is presented in the paper, and the correction of circular instrument image in substation environment is realized. First of all, the digital image processing technology is used to pre-process the site image. Secondly, Canny operator is used for edge detection. According to the edge feature points, the equipment area is detected and the regional parameters can be computed. Then the perspective transformation is used to correct the image, and the positive image of the circular instrument image is obtained. Finally, the corrected tilt image is done by the rotation operation. Experimental results show that the algorithm can realize image rectification, which is simple with fast speed and high precision. The proposed method is helpful for the further recognition.

Multi-photon parametric magnetic resonance in a miniature vapor cell is demonstrated. Much more multi-photon magnetic resonance can be observed when the radio frequency field becomes stronger. The linewidth of the n photons magnetic resonance equals that of the first-order resonance divided by n, which means that the uncertainty of the magnetic sublevel is reduced by the factor n. The signal-to-noise ratio can be improved when the low-frequency multi-photon resonance takes place, which finds a possible application in precision magnetic field measurement.

We experimentally demonstrate a simple modulation-free scheme for offset locking the frequency of a laser using buffer gas-induced resonance. Our scheme excludes the limitation of low diffraction efficiency and laser input intensity when an acousto-optic modulator is applied to shift the laser frequency from the resonance. We show the stabilization of a strong 795-nm laser detuned up to 550 MHz from the 87Rb 5S1/2F=2->5P1/2 F'=2 transition. The locking range can be modified by controlling the buffer gas pressure. A laser line width of 2 MHz is achieved over 10 min.

Differential evolution (DE) is one of the most efficient evolutionary algorithms for solving numerical optimization problems; however, it still suffers from premature convergence and stagnation. To address these problems, we propose a population state evaluation (PSE)-based improvement framework that can be freely embedded into various existing DE variants and population-based metaheuristic algorithms. The PSE framework comprises two population state evaluation mechanisms: one for tracking the optimization state of the population during evolution and the other for evaluating the distribution state of individuals in the population to identify the specific problem (premature convergence or stagnation) encountered by the corresponding algorithm. In addition, we design two intervention operations (dispersion and aggregation) to address premature convergence and stagnation. To verify the effectiveness of the PSE framework, we conduct comparison experiments using nine algorithms (including two basic DE algorithms, six state-of-the-art DE variants, and one non-DE algorithm) to optimize four real-world problems and 59 test functions from the IEEE CEC 2014 and IEEE CEC 2017 testbeds. The experimental results show that the PSE framework can significantly improve the optimization performance of the existing algorithms. [ABSTRACT FROM AUTHOR]