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11.
New technologies are highly interactive. They promote imaginative involvement and allow the experience of different self-states, such as those involving withdrawal or “psychic retreat”. According to Steiner, psychic retreats are areas of the mind populated by imagination and ideas which are poorly aligned with reality. Psychic retreats are not necessarily pathological in themselves—for instance, they can be used positively for counteracting anxiety or enhancing creativeness. However, with technological addiction there is a misuse of psychic retreat: here the total absorption with computer applications serves to hide painful or unbearable states of mind, and to protect the patient from overwhelming feelings through segregating self-states with a disconnection in their representations. Therefore, in clinical work with individuals suffering from technological addiction exploring the use of psychic retreats can serve as an aid to both diagnosis and treatment. Where the dysfunctional use of new technologies constitutes a temporary withdrawal from a specific painful event, this can have the function of protecting the individual from inner conflict; in the most serious cases however, technological addiction is grounded in more chronic and pathological dissociative mechanisms, and serves to prevent the mind from reactivating traumatic states connected to childhood experience of emotional neglect or abuse. While it is likely that the first condition can be positively handled with appropriate identification and treatment, the latter is much more difficult to deal with, particularly where the addictive behavior hides the weakness of the self, and psychic retreats are pervasively used to protect the patient from mental breakdown. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
12.
This paper describes a rapid method for confirming residues of thyreostats in meat-based baby foods by using liquid chromatography – dual polarity electrospray – tandem mass spectrometry (LC-ES(±)-MS/MS). Six thioureylenes, belonging to the group of thiouracil and imidazole, were selected for this work: thiouracil (TU), methylthiouracil (MTU), propylthiouracil (PTU), phenylthiouracil (PhTU), mercaptobenzimidazole (MBI) and tapazole (TAP).

The amphoteric nature of these compounds allows their electrospray detection in both positive and negative ionisation. Nevertheless, MS detection is not favoured by their low molecular weights, while their chromatographic retention is also thwarted by their high polarity. A pentafluorophenyl (PFP) core-shell phase column was selected to avoid peak asymmetry or peak splitting, and a dual-polarity ionisation method was optimised to obtain a sensitivity as high as possible. The method was validated according to the Commission Decision 657/2002/EC. A simple and fast procedure based on matrix solid phase dispersion (MSPD) was optimised to extract analytes from baby foods with recoveries exceeding 82%. Limit of decision (CCα) and detection capability (CCβ) were lower than the permissible maximum concentration (10 ng g?1). The validated method was then applied to assess the potential occurrence of the six selected thyreostats in nine commercial products. All the samples were found free of contamination.  相似文献   
13.
The synthesis and structural characterization of copolymers of 1-[(2-acryloyloxy) ethoxycarbonyl]thioxanthone (ATX) with 1-[4-(2-acryloyloxyethylthio)phenyl]-2-methyl-2-morpholino-propan-1-one (AMMP), as well as ATX, AMMP and n-butyl acrylate (BA) terpolymers, is reported. These copolymeric systems have been checked in the photoinitiated polymerization in film matrix of the 1,6-hexanediol diacrylate (HDDA)–BA equimolar mixture under UV irradiation over 380 nm, i.e., under conditions simulating a TiO2-pigmented acrylic coating formulation, and compared with the corresponding mixture of low-molecular-weight structural models 1-[(2-isobutyroyloxy)ethoxycarbonyl]thioxanthone (ITX) and 1-[4-(2-isobutyroyloxyethylthio)phenyl]-2-methyl-2-morpholino-propan-1-one (IMMP). The much higher photoinitiation activity shown by the copolymers is discussed in terms of close vicinity of thioxanthone and α-morpholinoacetophenone moieties along the backbone, which favors the excitation energy transfer from the former to the latter photosensitive group. © 1995 John Wiley & Sons, Inc.  相似文献   
14.
Modelling the mechanical effect of muscles is important in several research and clinical contexts. However, few studies have investigated the effect of different muscle discretizations from a mechanical standpoint. The present study evaluated the errors of a reduced discretization of the lower-limb muscles in reproducing the muscle loading transferred to bones. Skeletal geometries and a muscle data collection were derived from clinical images and dissection studies of two cadaver specimens. The guidelines of a general method previously proposed for a different anatomical district were followed. The data collection was used to calculate the mechanical effect of muscles, i.e. the generalized force vectors, and the errors between a large and a reduced discretization, in a reference skeletal pose and in the extreme poses of the range of motion of joints. The results showed that the errors committed using a reduced representation of muscles could be significant and higher than those reported for a different anatomical region. In particular, the calculated errors were found to be dependent on the individual anatomy and on the skeletal pose. Since different biomechanical applications may require different discretization levels, care is suggested in identifying the number of muscle lines of action to be used in musculoskeletal models.  相似文献   
15.
Heat‐shock protein 90 (Hsp90) is a molecular chaperone involved in the stabilization of key oncogenic signaling proteins, and therefore, inhibition of Hsp90 represents a new strategy in cancer therapy. 2‐Amino‐7‐[4‐fluoro‐2‐(3‐pyridyl)phenyl]‐4‐methyl‐7,8‐dihydro‐6H‐quinazolin‐5‐one oxime is a racemic Hsp90 inhibitor that targets the N‐terminal adenosine triphosphatase site. We developed a method to resolve the enantiomers and evaluated their inhibitory activity on Hsp90 and the consequent antitumor effects. The (S) stereoisomer emerged as a potent Hsp90 inhibitor in biochemical and cellular assays. In addition, this enantiomer exhibited high oral bioavailability in mice and excellent antitumor activity in two different human cancer xenograft models.  相似文献   
16.
The production of polyhydroxyalcanoates (PHAs), which are biodegradable plastics, was studied using milk whey and dairy wastewater activated sludge to define a suitable C/N ratio, the pre-treatments required to reduce the protein content, and the effect of pH correction. The results show good production of PHAs at a C/N = 50 and without pH correction. The use of dairy wastewater activated sludge has the advantage of not requiring aseptic conditions.  相似文献   
17.
Network-controlled device-to-device (D2D) communication allows cellular users to communicate directly, i.e., without passing through the eNodeB, while the latter retains control over resource allocation. This allows the same time–frequency resources to be allocated to spatially separated D2D flows simultaneously, thus increasing the cell throughput. This paper presents a framework for: (1) selecting which communications should use the D2D mode, and when, and (2) allocating resources to D2D and non-D2D users, exploiting reuse for the former. We show that the two problems, although apparently similar, should be kept separate and solved at different timescales in order to avoid problems, such as excessive packet loss. We model both as optimization problems, and propose a heuristic solution to the second, which must be solved at millisecond timescales. Simulation results show that our framework is practically viable, it avoids the problem of packet losses, increases throughput and reduces delays.  相似文献   
18.
In this paper, we present an approach to interactive out-of-core volume data exploration that has been developed to augment the existing capabilities of the LhpBuilder software, a core component of the European project LHDL (). The requirements relate to importing, accessing, visualizing and extracting a part of a very large volume dataset by interactive visual exploration. Such datasets contain billions of voxels and, therefore, several gigabytes are required just to store them, which quickly surpass the virtual address limit of current 32-bit PC platforms. We have implemented a hierarchical, bricked, partition-based, out-of-core strategy to balance the usage of main and external memories. A new indexing scheme is introduced, which permits the use of a multiresolution bricked volume layout with minimum overhead and also supports fast data compression. Using the hierarchy constructed in a pre-processing step, we generate a coarse approximation that provides a preview using direct volume visualization for large-scale datasets. A user can interactively explore the dataset by specifying a region of interest (ROI), which further generates a much more accurate data representation inside the ROI. If even more precise accuracy is needed inside the ROI, nested ROIs are used. The software has been constructed using the Multimod Application Framework, a VTK-based system; however, the approach can be adopted for the other systems in a straightforward way. Experimental results show that the user can interactively explore large volume datasets such as the Visible Human Male/Female (with file sizes of 3.15/12.03 GB, respectively) on a commodity graphics platform, with ease.  相似文献   
19.
N-(5-Bromo-1,3-thiazol-2-yl)butanamide (compound 1) was found active (IC50=808 nM) in a high throughput screening (HTS) for CDK2 inhibitors. By exploiting crystal structures of several complexes between CDK2 and inhibitors and applying structure-based drug design (SBDD), we rapidly discovered a very potent and selective CDK2 inhibitor 4-[(5-isopropyl-1,3-thiazol-2-yl)amino] benzenesulfonamide (compound 4, IC50=20 nM). The syntheses, structure-based analog design, kinases inhibition data and X-ray crystallographic structures of CDK2/inhibitor complexes are reported.  相似文献   
20.
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