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摘要： BACKGROUND: Vulvar masses in adolescents have a broad differential diagnosis, yet few reports exist detailing masses of mammary origin. CASE: A nulliparous, healthy 16-year-old adolescent presented with a longstanding, ulcerated, 17-cm vulvar mass of unknown origin and pronounced inguinal lymphadenopathy. The patient underwent a left radical partial vulvectomy, with pathology revealing terminal duct lobular units consistent with polymastia. CONCLUSION: Differential diagnosis of a vulvar mass in an adolescent should include polymastia.

关键词： Myasthenia   Nonagenarian   Mitochondrial   Repetitive nerve stimulation   Ptosis   Double vision  

关键词： Uncertainty   Stochastic processes   Measurement uncertainty   Particle measurements   Atmospheric measurements   Differential games   Motion measurement   Application to finance   backward stochastic differential equations (BSDEs)   stochastic control  

摘要： This article presents a problem on model uncertainties in stochastic control, in which an agent assumes a best case scenario on one risk and at the same time a worst case scenario on another risk. Particularly, the agent maximizes its view on a Brownian motion, simultaneously minimizing its view on another Brownian motion in choice of a probability measure. This selection method of a probability measure generalizes an approach to model uncertainties in which one considers the worst case scenarios for the views on Brownian motions, such as in the robust control. Specifically, we newly formulate and solve this problem based on a backward stochastic differential equation (BSDE) approach as a sup-inf (resp., inf-sup) optimal control problem on choice of a probability measure with the control domains dependent on stochastic processes. Concretely, we show that under certain conditions, the sup-inf and inf-sup problems are equivalent and these are solved by finding a solution of a BSDE with a stochastic Lipschitz driver. Then, we investigate two cases in which the optimal probability measure is explicitly obtained. The expression of the optimal probability measure includes signs of the diffusion terms of the value process, which are hard to determine in general. In these cases, we show two methods of determining the signs:the first one is by comparison theorems, and the second one is to predetermine the signs a priori and confirm them afterward by explicitly solving the corresponding equations.

关键词： barley grain   thermal stress   dietary fibber   phenolic compounds   antioxidant capacity  

摘要： BACKGROUND Barley (Hordeum vulgare L.) is a healthy grain because of its high content of dietary fibre and phenolic compounds. It faces periods of high temperature during grain filling, frequently reducing grain weight. Heat stress may also affect some of the bioactive compounds present in the grain. To produce quality grains that provide nutritional and health benefits, it is important to understand the effect of environmental stresses on the quantity and quality of bioactive compounds. RESULTS We have studied the effect of post-anthesis thermal stress on barley bioactive compounds and antioxidant capacity under Mediterranean field conditions during two consecutive growing seasons in four barley genotypes. Thermal stress affected grain weight and size and changed the relative composition of bioactive compounds. The relationship between heat stress and grain beta-glucans and arabinoxylans content was indirect, as the resulting increases in concentrations were due to the lower grain weight under stress. Conversely, heat stress had a significant direct impact on some phenolic compounds, increasing their concentrations differentially across genotypes, which contributed to an improvement in antioxidant capacity of up to 30%. CONCLUSION Post-anthesis thermal stress had a significant effect on beta-glucans, arabinoxylans, phenolic compound concentration and antioxidant capacity of barley grains. Final grain quality could, at least partially, be controlled in order to increase the bioactive concentrations in the barley grain, by cultivation in growing areas prone to heat stress. Late sowings or late flowering genotypes could also be considered, should a premium be implemented to compensate for lower yields. (c) 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

关键词： Insulated gate bipolar transistors   Interference   Wires   Aging   Switches   Monitoring   Impedance   On-line monitoring   bond wires   differential mode conducted interference   insulate gate bipolar transistor   phase-frequency characteristics  

摘要： This paper presents an on-line monitoring method of IGBT module bond wires aging based on the phase-frequency characteristics (PFCs) of differential mode (DM) interference signal. Firstly, the collector current variation during IGBT chip switching is analyzed, and the relationship between the aging degree of bond wires and the PFCs of DM interference signal is studied;Secondly, a phase angle characteristic measurement system of DM interference signal is built and used to online monitor the aging of bond wires in IGBT module;Finally, taking the buck converter composed of IGBT module as the equipment under tested, the interference signal is extracted by the RF current probe and processed by the low-pass filter and signal amplifier, then the phase angle characteristics are measured by the oscilloscope board to realize the on-line monitoring of the bond wires aging of IGBT module. The experimental results show that compared with buck converter with healthy IGBT module, the phase angle of DM interference signal in Buck Converter with aging IGBT module is reduced. The proposed method does not need expensive equipment such as spectrum analyzer, and only needs to monitor the aging state of bond wires in IGBT module online through oscilloscope board. Besides, the research method in this paper provides an approximate linear monitoring method for bonding wire lift-off.

关键词： Disinfection  

摘要： SIGNIFICANCE This investigation examines the effectiveness of several common contact lens solutions in the disinfection of Acanthamoeba, which causes a serious eye infection most often resulting from dysfunctional or improper use of contact lens products. PURPOSE Acanthamoeba keratitis is an eye infection caused by a free-living amoeba, which can lead to extensive corneal damage and frequently blindness. Acanthamoeba keratitis is linked with contact lens use combined with noncompliance with contact lens care cleaning regimens. The patient's choice and use of multipurpose solutions (MPSs) continue to be a risk factor for Acanthamoeba keratitis. Thus, it is critical that the Acanthamoeba disinfection efficacy of the popular MPSs be determined. Here we compare the efficacy of seven major MPSs on the global market. METHODS Using standard methods of Acanthamoeba disinfection and quantification, Acanthamoeba ATCC 30461, 30868, 50370, and 50676 trophozoites were inoculated into each MPS and held for the manufacturer's recommended disinfection time. Acanthamoeba recovery plates were incubated for 14 days, after which positive wells were identified and cell concentrations determined using the 50% endpoint method. RESULTS Members of the OPTI-FREE products (Express, Replenish, and Puremoist [Alcon, Fort Worth, TX]) demonstrated significantly higher percentages of antimicrobial activity compared with the renu Advanced Formula (Bausch + Lomb, Rochester, NY), Biotrue (Bausch + Lomb), Acuvue RevitaLens (Johnson & Johnson, Santa Ana, CA), and Lite products (Cooper Vision, Scottsville, NY) for four of the trophozoite strains tested. CONCLUSIONS Many of the popular MPS biocides maintain little or no antimicrobial activity against Acanthamoeba trophozoites, and the number of biocides in an MPS does not necessarily indicate its antimicrobial activity.

关键词： coupled plasmon waveguide resonance   differential intensity interrogation   refractive index sensor   C-band  

摘要： We proposed a differential fiber-optic refractive index sensor based on coupled plasmon waveguide resonance (CPWR) in the C-band. The sensor head is a BK7 prism coated with ITO/Au/ITO/TiO2 film. CPWR is excited on the film by the S-polarized components of an incident light. The narrow absorption peak of CPWR makes it possible to realize dual-wavelength differential intensity (DI) interrogation by using only one incident point. To implement DI interrogation, we used a DWDM component to sample the lights with central wavelengths of 1529.55 and 1561.42 nm from the lights reflected back by the sensor head. The intensities of the dual-wavelength lights varied oppositely within the measurement range of refractive index, thus, a steep slope was produced as the refractive index of the sample increased. The experimental results show that the sensitivity is 32.15/RIUs within the measurement range from 1.3584 to 1.3689 and the resolution reaches 9.3 x 10(-6) RIUs. Benefiting from the single incident point scheme, the proposed sensor would be easier to calibrate in bio-chemical sensing applications. Moreover, this sensing method is expected to be applied to retro-reflecting SPR sensors with tapered fiber tip to achieve better resolution than wavelength interrogation.

关键词： Sliding modes   Super-twisting algorithm   Finite-time convergence   Fixed-time convergence   Disturbance rejection  

摘要： The problem of exactly differentiating a signal with bounded second derivative is considered. A class of differentiators is proposed, which converge to the derivative of such a signal within a fixed, i.e., a finite and uniformly bounded convergence time. A tuning procedure is derived that allows to assign an arbitrary, predefined upper bound for this convergence time. It is furthermore shown that this bound can be made arbitrarily tight by appropriate tuning. The usefulness of the procedure is demonstrated by applying it to the well-known uniform robust exact differentiator, which is included in the considered class of differentiators as a special case. (C) 2021 The Author(s). Published by Elsevier Ltd.

关键词： Routing   Optimization   Predictive models   Layout   Power cables   Crosstalk   Prediction algorithms   Differential evolution (DE)   electronic systems   ensemble learning (EL)   machine learning (ML)   optimization  

摘要： In this article, a method for solving cable layout optimization problems in electronic systems based on ensemble learning (EL) and improved differential evolution (DE) algorithm is proposed. Using this method, we produced two cable layout schemes with the considerations of the electromagnetic compatibility performance and the total length of cables. First, several different individual machine learning (ML) models for all output variables were established. On this basis, we established EL models with better performance than previous individual ML models. Then, aiming at the optimization problem presented in this article, an improved DE algorithm was proposed. On this basis, a method for solving cable layout optimization problems in electronic systems based on EL and the improved DE algorithm was proposed. Finally, the effectiveness of the proposed method was verified by two examples of electronic system cable layout optimization with different routing modes. Each example problem was solved using four different methods. The results indicate that the method proposed here outperformed existing methods.

关键词： Constrained production optimization   Classification   Support vector machine (SVM)   Surrogate model   Radial basis function (RBF)  

摘要： Recently, evolutionary algorithms (EAs) are becoming more and more popular in oil industry. It should be noted that the existence of various state constraints largely decreases the efficiency of EAs. In this paper, a doublemodel differential evolution (CSDE) is proposed for waterflooding production optimization with nonlinear inequality constraints. There are two main stages in CSDE: 1) the boundary of feasible region is explicitly constructed by a classifier, support vector machine (SVM), to prescreen the feasible solutions from current population, and 2) the objective function is approximated by radial basis function (RBF) surrogate model which can be used to select the best individual among feasible solutions. It is worth noticing that problems with a large number of constraints can be significantly simplified by distinguishing the feasible solutions and infeasible solutions with one unique SVM classifier. To the best of our knowledge, this is the first foray to integrate SVM and RBF into evolutionary algorithm for waterflooding optimization problem. The CSDE method has been tested on three artificial cases: three-channel, PUNQ-S3 and SPE9. The test results demonstrate that CSDE algorithm can handle constraints more efficient and achieve higher net present value (NPV) compared with the original EAs and other single-model algorithms.