改性十六烷基甜菜碱表面活性剂在个人护理品中的应用

开发了一种温和的源自天然原料的表面活性剂。它能够与各种水溶助长性表面活性剂复配并有效地提高护发和护肤产品的温和性、黏度及发泡性。     

Unbiased stereological estimation of the rat fetal pituitary volume and of the total number and volume of TSH cells after maternal dexamethasone application

Glucocorticoids have an inhibitory influence on proliferation activity of the pituitary cells while stimulating apoptosis. Therefore, it was hypothesized that the synthetic glucocorticoid, dexamethasone (DX), has an inhibitory influence on the number of thyroid‐stimulating hormone (TSH) cells during fetal development. The effects of maternal administration of DX on stereological parameters of TSH cells, and TSH serum concentration were investigated in 21‐day‐old rat fetuses. On day 16 of pregnancy, the experimental dams received 1.0 mg DX/kg b.w. subcutaneously, followed by 0.5 mg DX/kg b.w./day on days 17 and 18 of gestation. The control gravid females received the same volume of saline vehicle. TSH cells were stained immunocytochemically by the peroxidase–antiperoxidase (PAP) method. The fetal pituitary volumes were estimated using Cavalieri's principle. A physical disector counting technique in combination with the fractionator sampling method was used for estimation of pituitary TSH cell number. Cell and nuclear volumes were measured with a planar rotator. Maternal DX application was found to cause a significant decrease of pituitary volume and number of TSH cells per pituitary in 21‐day‐old fetuses in comparison with the control fetuses. TSH cell number expressed per body weight unit declined significantly after maternal DX administration. These results indicate an inhibitory DX influence on proliferative activity of precursors and likely differentiated TSH cells and increased apoptotic prevalence. The histological appearance, volume of TSH cells and TSH serum concentration suggest intensive synthetic activity in TSH cells of DX exposed fetuses. Microsc. Res. Tech. 73:1077–1085, 2010. © 2010 Wiley‐Liss, Inc.     

Study on the Implementation of Optical Transparent Transport Networks in the European Environment—Results of the Research Project COST 239

Photonic Network Communications -     

Controlled experiment replication in evaluation of e-learning system’s educational influence

We believe that every effectiveness evaluation should be replicated at least in order to verify the original results and to indicate evaluated e-learning system’s advantages or disadvantages. This paper presents the methodology for conducting controlled experiment replication, as well as, results of a controlled experiment and an internal replication that investigated the effectiveness of intelligent authoring shell eXtended Tutor–Expert System (xTEx-Sys). The initial and the replicated experiment were based on our approach that combines classical two-group experimental design and with factoral design. A trait that distinguishes this approach from others is the existence of arbitrary number of checkpoint-tests to determine the effectiveness in intermediate states. We call it a pre-and-post test control group experimental design with checkpoint-tests. The gained results revealed small or even negative effect sizes, which could be explained by the fact that the xTEx-Sys’s domain knowledge presentation is rather novel for students and therefore difficult to grasp and apply in earlier phases of the experiment. In order to develop and improve the xTEx-Sys, further experiments must be conducted.     

Modelling the Environment of a Mobile Robot with the Embedded Flow State Machine

A type of topological approach to mobile robot navigation is discussed and experimentally evaluated. The environment as experienced by a moving robot is treated as a dynamical system. Simple types of reactive behavior are supplemented with eventual decisions to switch between them. When switching criteria are defined, the system may be described in the form similar to a finite state machine. Since it is embedded in the environment and dependent on the sensory flow of the robot, we introduce the term “Embedded flow state machine” (EFSM). We implemented it with a recurrent neural network, trained on a sequence of sensory contents and actions. One of the main virtues of this approach is that no explicit localization is required, since the recurrent neural network holds the state implicitly. The EFSM is applicable to multi-step prediction of sensory information and the travelled distances between decision points, given a sequence of decisions at decision points. Thus, the optimal path to a specified goal can be sought. One of the main issues is, for how many steps ahead the prediction is reliable enough. In other words, is it feasible to perform environment modelling and path planning in this manner? The approach is tested on a miniature mobile robot, equipped with proximity sensors and a color video camera. Decision ‘points,’ where deviations from the wall-following behavior are allowed, are based on color object recognition. In the case of an experimental environment of medium complexity, this approach was successful.     

Fabrication of SiC by carbothermal-reduction reactions of diatomaceous earth

In this paper the possibility of using diatomaceous earth as Si precursor for low temperature synthesis of silicon carbide (SiC) by carbothermal-reduction reactions was studied. A diatomaceous earth of Serbian origin and carbon black as reducing agent were used. The green bodies with constant C/SiO₂ ratio (C/Si = 4) were heated at temperatures between 1,250 °C and 1,550 °C with controlled Ar flow atmosphere. Phase evolution was followed as a function of annealing time and sintering temperature. It was found that reaction proceeded via many intermediate phases. The comparatively low reaction temperature is attributed to the nano-porous nature of the raw material. By means of XRD and SEM investigations powders have been characterized. The results show that diatomaceous earth can be very effective source for obtaining of silicon carbide powders.     

The role of surface characteristics in directing subsurface spatial planning processes: The case study of a high-speed railway in Slovenia

An increased need for subsurface use has been recently noticed. At the same time, problems concerning planning procedures, licensing issues and environmental impact assessments of subsurface projects have been recognised. This paper considers the applicability and usefulness of spatial modelling within the scope of planning, assessing and evaluating subsurface projects. As a case study a high-speed railway in Slovenia (HSR) was examined. Special emphasis was given to the role of surface characteristics in directing subsurface spatial planning processes, since the characteristics of the subsurface are often uncertain and not sufficiently represented in existing data. A new planning method consisting of three consecutive phases was developed. The approach was based on spatial vulnerability, attractiveness and suitability models, supported by GIS. The results of HSR planning showed, that the method is particularly useful if applied in the early planning phases. The results were aimed to support the decision-making process in order to proceed towards optimal spatial solutions for the project.     

CMOS NAND and NOR Schmitt circuits

Original solutions of m-input NAND and NOR logic circuits with hysteresis in the transfer characteristics are proposed. Multiple inputs are done similarly to standard NAND and NOR logic circuits. The logic circuits proposed in this paper consist of 2m + 1 paris of enhancement CMOS transistors. The hysteresis voltage depends on supply voltage and transistor geometry. The proposed solutions always guarantee hysteresis, even with very large process variations. The noise immunity is typically greater than 50% of supply voltage. Analysis using simple device models together with computer simulations and experimental results is given.     

EXAMINATION OF RHEOLOGICAL PROPERTIES OF FINE PARTICLES AS CARRIERS FOR CONTROLLED DRUG RELEASE

Development of lipid-based fine particles as potential drug carriers requires detailed investigation of possible effects of these carriers on rheological properties of blood. In this study, we have investigated the influence of dynamic conditions on aggregate formation and stability in dispersions of lipid-based fine particles in whole blood under in vitro conditions. Rheological parameters of two concentrations of liposome dispersion and two concentrations of lipid emulsion in blood were studied by assessing shear stress/shear rate relationships. The magnitude of attractive interactions between aggregates and/or particles, A, and the effective-to-real volume fraction of particles, ϕ f /ϕ p , were estimated for rheological quantification of lipid-based fine particles-blood interactions and aggregate stability. Addition of lipid-based particles induced aggregate formation in blood, which was more pronounced at higher concentrations of lipid-based fine particles. Furthermore, larger and more stable aggregates were formed in liposome dispersions as compared to lipid emulsions in blood.