212Pb: Production Approaches and Targeted Therapy Applications

Over the last decade, targeted alpha therapy has demonstrated its high effectiveness in treating various oncological diseases. Lead-212, with a convenient half-life of 10.64 h, and daughter alpha-emitter short-lived 212Bi (T1/2 = 1 h), provides the possibility for the synthesis and purification of complex radiopharmaceuticals with minimum loss of radioactivity during preparation. As a benefit for clinical implementation, it can be milked from a radionuclide generator in different ways. The main approaches applied for these purposes are considered and described in this review, including chromatographic, solution, and other techniques to isolate 212Pb from its parent radionuclide. Furthermore, molecules used for lead’s binding and radiochemical features of preparation and stability of compounds labeled with 212Pb are discussed. The results of preclinical studies with an estimation of therapeutic and tolerant doses as well as recently initiated clinical trials of targeted radiopharmaceuticals are presented.

Optimization of VRR for Cold Chain with Minimum Loss Based on Actual Traffic Conditions

Recently, fresh agricultural cold-chain logistics have been greatly developed with the increasing needs of people’s life. Reducing costs of cold-chain distribution has become the main object of loss control in logistics enterprises. The objective of this research is to find a set of optimal routes that minimize the total loss, including fuel cost, refrigeration cost, soft time window penalty cost, and cargo damage cost over transit time. In this paper, the definition and model construction of vehicle routing problem (VRP) with multiobjective minimum lost are introduced first. Then, an ant colony optimization (ACO) algorithm combined with Pareto local search (PLS) is put forward to solve the minimum loss model. In order to avoid the influence of complex road conditions during distribution, the distance matrix and the transit time matrix are both derived from the recommended navigation road based on E-map API. At last, a compare experiment between the traditional method and our proposed method is performed. The results indicate that our method has strong applicability and potential advantages in cold-chain logistic and has important practical significance and application value.

A Unified Switch Loss Model and Design Consideration for Multilevel Boost PFC With GaN Devices

Recently, multilevel converters with gallium nitride (GaN) devices have shown marvelous advantages for power factor correction (PFC) conversion to meet the increasingly higher efficiency and power density requirements. In the traditional design process for the multilevel PFC converter, it is necessary to separately optimize the devices of the corresponding breakdown voltage under different level number, which causes difficulty to the overall optimization of the entire system. In this paper, a unified minimum loss model for GaN switches regardless of voltage levels is proposed to optimize the efficiency based on device’s new figure-of-merit (NFoM) (NFoM = COSS(ER) RDS(on)). With the help of this unified minimum loss model, it simplifies the efficiency optimizing methodology according to the NFoMs of GaN devices for multilevel PFC converter. According to the methodology, a 2 kW cascaded H-bridge (CHB) PFC prototype is constructed to verify the design methodology, achieving over 99% efficiency with power density over 1000 W/in3 .

Research on resilience recovery strategy optimization of highway network after disaster based on genetic algorithm

In order to effectively improve the recovery efficiency of the highway network after the disaster and make the road network quickly recover to the normal operation level, the recovery strategy of the highway network after the disaster aiming at the optimal toughness was studied and formulated. First clear the toughness in this paper the definition and put forward the two toughness indexes, then constructs the model of road network resilience restored after a disaster, in considering the time, money, resources and cost conditions, through the corresponding genetic algorithm to solve, it is concluded that the shortest road repair, restore minimum loss in the process of recovery program. Finally, an example is given to illustrate how to use the model established in this paper. The results show that from the beginning of repair to the end of repair, the repair team can achieve the expected task in a faster time, which minimizes the performance loss of the road network and saves the cost.

Optimization of Return Channels of High Flow Centrifugal Compressor Stages by CFD-Methods

Calculations performed with modern computer fluid dynamics (CFD) programs aid in optimizing the flow path of a centrifugal compressor. The characteristics of the stator elements of the flow path, calculated by CFD methods, are considered to be quite accurate. Optimization of three-stage reverse-directing devices with a large flow rate (0.15) and different theoretical head coefficients (0.45; 0.60; 0.70) has been carried out. For optimizing return channels a parameterized model was created. Optimization was performed with MOGA (Multi-Objective Genetic Algorithm) optimization method in the Direct Optimization program of the ANSYS software package. The optimization goal was to achieve the minimum loss factor at the design point. In the optimization process, the following parameters were varied: the number of and the inlet angle of the vanes, the height of the vanes at the inlet, external and internal radii of curvature of the U-bend. For the return channel with a minimum loss coefficient, the dependences of this parameter on the flow coefficient were calculated. Comparison with the characteristics of the initial variant showed that the optimized return channels are more efficient over the entire flow range. Optimization allowed reducing the loss factor by 20%.

O que é preciso saber sobre microabrasão

Objective: Having in mind the growing value that is given to esthetic procedures it has been carried out a literature review about the main polemics that goes around Enamel Microabrasion technique. Action mechanism: the microabrasion compound modifies light refraction and reflection indexes producing an optical effect which allows the camouflage of the subsurface stains. Indications: the technique is indicated to remove any stain, since it is restrict to the most superficial layer of enamel. Advantages: immediate and permanent results with minimum loss of dental structure. Technique: with all care steps taken, a mixture of hydrochloric acid or phosphoric acid and pumice is applied to dental surface for 12 to 16 times, during 10 seconds each application. The application can be done manually or with the help of a low rotation hand-piece. Conclusions: the enamel microabrasion is an effective, safe and conservative technique if compared with other alternatives available. However, some authors affirm that it must be very carefully used because of enamel loss and risks of lesion by the acid.

SUBSTANTIATION OF THE PARAMETERS OF A HORIZONTAL CONVEYER-CLEANER OF ROOT CROPS

The paper covers theoretical substantiation of the rational parameters of a horizontal conveyer-cleaner of sugar beets providing their minimum loss during process performance. The procedure of conducting experimental investigations on the developed design of a horizontal conveyer-cleaner of root crops in configuration with a root crop harvester is presented. The results of the experimental research on determining root crop loss, damage and impurity depending on the design and kinematic parameters of a cleaner are provided. In order to choose the rational parameters, specific recommendations are provided.