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31.
The feeding-deterrence properties of crude extracts of three Brazilian octocoral species, Neospongodes atlantica Kükenthal (Alcyonacea, Nephtheidae), Plexaurella regia Castro (Gorgonacea, Plexauridae), and Phyllogorgia dilatata Esper (Gorgonacea, Gorgoniidae), were investigated. All the extracts were incorporated into food strips at the concentrations occurring in the living organisms. Crude extract and its ethyl acetate fraction obtained from P. dilatata collected in Armação dos Búzios (Rio de Janeiro State), when incorporated into artificial diets and tested in the habitat of origin, reduced consumption of food strips by fishes, relative to controls. Crude extracts from two octocoral species collected at the National Marine Park of Abrolhos (Bahia State), N. atlantica and P. regia, had no apparent feeding-deterrence properties; in fact, they seemed to stimulate feeding. Bioassay-guided fractionation of the bioactive P. dilatata crude extract revealed that the deterrent property was restricted to a medium polarity fraction. Field palatability experiments with two pure compounds isolated from this fraction revealed that the furanocembranolide 11,12-epoxypukalide is a potent feeding deterrent produced by P. dilatata against fish. Apparently, furanocembranolides are a particular class of compounds with feeding deterrent properties, protecting some octocorals from potential fish predator species in both tropical and temperate environments.  相似文献   
32.
In this replication and extension of a national survey of psychotherapists conducted in 1987, American psychologists (n = 219), counselors (n = 191), and social workers (n = 192) reported in 2007 on the processes and outcomes of their personal therapy experiences. Of the 85% who sought therapy at least once, women, men, and members of all three professions were equally as likely to have received personal treatment. Their top reasons for seeking therapy were marital–couple distress (20%), depression (13%), need for self-understanding (12%), and anxiety–stress (10%). Approximately 24% used psychotropic medication in combination with personal therapy. More than 90% of therapists reported positive outcomes across multiple domains. The modal lasting lessons from personal treatment related to therapist reliability, skill, and empathy. The results are tentatively compared with those obtained in 1987, thus chronicling the evolution of personal therapy among psychologists and social workers during the past 20 years. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
33.
Many uses of protein hydrolysates have been developed and applied to areas such as nutritional therapy, culture media, and the isolation of biologically active peptides. All these applications need carefully controlled and characterized hydrolysates. In order to produce such a type of hydrolysate, it is possible to use haemoglobin which is a very well defined and constant protein source. Enzymic hydrolysis of haemoglobin by pepsin was carried out at pilot-plant scale in an ultrafiltration reactor with mineral membranes. The object was to obtain a reproducible, decolorized, salt-free enzymic hydrolysate. Two types of membranes were tested having 10000 dalton (M5 type) and 20000 dalton (M4 type) cut-offs. Little significant difference was observed in the final products when both types of membranes were used. Reproducibility of hydrolysates was verified by amino acid analysis and gel filtration chromatography. The haemoglobin hydrolysates produced contained more than 90% protein and are especially suitable for fine applications.  相似文献   
34.
A primary means of demonstrating the feasibility and effectiveness of fiber-reinforced polymer (FRP) composite bridge materials is via in situ bridge load testing. For this study, the prescribed or assumed design factors for each of the study bridges were compared to those exhibited by the performance of the bridge. Specifically, the wheel load distribution factors and impact factors as defined by AASHTO were considered in order to assess the load transfer and distribution in structures utilizing FRP panels. The in situ testing configurations for the study bridges are outlined, including the truck and instrumentation placement to obtain the desired information. Furthermore, comparisons were drawn between the design values for deflection and those experienced by the structures during testing. It was found that although the deflections exhibited by the bridges were well within the design limits, further research is needed to be able to prescribe bridge design factors for FRP panels.  相似文献   
35.
Andronescu  Mirela  Dees  Danielle  Slaybaugh  Laura  Zhao  Yinglei  Condon  Anne  Cohen  Barry  Skiena  Steven 《Natural computing》2003,2(4):391-415
We present an efficient algorithm for determining whether all moleculesin a combinatorial set of DNA or RNA strandsare structure free, and thus availablefor bonding to their Watson-Crick complements.This work is motivated by the goalof testing whether strands used in DNAcomputations or as molecular bar-codesare structure free, where the strands areconcatenations of short words. We alsopresent an algorithm for determining whetherall words in S*, for some finite setS of equi-length words, are structure free. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
36.
LiNiPO4 belongs to a family of olivine type compounds, with members LiMPO4 where M = Fe, Mn, Co or Ni are transition metals. The lithium nickel phosphate was prepared and characterized in order to evaluate a new potential cathode material for our ongoing research in aqueous rechargeable batteries. Annealing the final product is critical in obtaining the stoichiometric LiNiPO4 pure phase; conventional cooling to a room temperature leads to an indication of Li3PO4 and NiO secondary phases as impurities. The synchrotron infrared radiation (SR-IR) as a source for IR spectroscopy pins down the differences in the chemical bonding for annealed and conventional cooled LiNiPO4 samples. The cyclic voltammetric and galvanostatic studies showed annealed LiNiPO4 is electrochemically active from which lithium ions can be de-intercalated during oxidation process leading to an amorphous NiPO4 and a minor product of nickel(II) hydroxide (β-NiOOH). During subsequent reduction, lithium ions are not fully intercalated, however, the structure is reversible and adequate for multiple cycles. The high potential in LiNiPO4 looks to be very attractive in terms of high energy density, given the efficiency is improved.  相似文献   
37.
38.
Cocaine use is a significant problem among methadone maintenance clients. Contingency management (CM) is a reinforcement-based approach with demonstrated efficacy for reducing cocaine use. This study examines whether the efficacy of CM treatment for cocaine-dependent individuals receiving methadone maintenance for opioid dependence differs by ethnicity. Participants were 191 African American, Hispanic, and White cocaine-dependent methadone maintenance clients, randomly assigned to standard methadone treatment or standard methadone treatment plus CM for 12 weeks. Hispanic participants were younger, less educated, and reported fewer years of cocaine use than did African American and White participants and reported fewer years of heroin use than did African American participants. African American participants were less likely to report a history of psychiatric symptoms or treatment in comparison with Hispanic and White participants. While CM was associated with longer duration of continuous cocaine abstinence and a greater proportion of submitted urine samples negative for cocaine, ethnicity was not related to treatment outcomes, and there was no significant interaction between treatment and ethnicity. CM appears to be an efficacious treatment for cocaine dependence among methadone maintenance clients, regardless of ethnicity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
39.
The Saguenay St. Lawrence Marine Park (SSLMP) and the adjacent Marine Protected Area (MPA) in the St. Lawrence Estuary, in Quebec, cover a territory of exceptional biodiversity including 12 species of marine mammals, nearly half of which are considered to be endangered species. Whale-watching trips and other human activities related to commercial shipping, tourism, and recreation generate very intensive traffic in the area, which pose cumulative threats to the marine wildlife. This study has been undertaken in collaboration with the Marine Park and the MPA managers to develop a multi-agent system (MAS) to investigate the interactions between the traffic and the marine mammals in the estuary. This paper describes the first prototype version of the proposed MAS model where the focus is on the whale-watching boats. It discusses the conceptual model with its principal components: the physical environment and the boat agents and whale entities, and the implementation of the model with the behavior rules of the agents. In this version of the MAS, the whale-watching boats are represented as cognitive agents while the whales are simple reactive entities. The prototype model was implemented in the agent-based modeling platform RePast. An index, the happiness factor (i.e., the ratio of whale observation time over the trip duration) was designed to measure how successful the boat agents are in achieving their goal. Simulations were run to assess different decision strategies of the boat agents and their impacts on the whales. Results show that cooperative behavior that involves a combination of innovator and imitator strategies yields a higher average happiness factor over non-cooperative, purely innovators, behavior. However, this cooperative behavior creates increased risk for the whale populations in the estuary.  相似文献   
40.
The purpose of my writing this essay is to familiarize readers with an interesting projective device called the O.R.T. (the Object Relations Technique), which has been described by James Grotstein as “an innovative and unique descendent of the heritage of projective testing on one hand and of projective aspects of psychoanalytic clinical technique on the other (1993, pp. 1).” It is an objectified (operationalized) method for the assessment of an individual’s actual, underlying models for relationship that has been employed primarily as a clinical therapeutic tool. Its history is as interesting as the technique itself. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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