Initial Link Research Articles

Biological activities of collagen peptides obtained by enzymic Hydrolysis from Far-Eastern holothurians

The certain sea cucumbers are the marine animals which are important as human delicacy food source. In addition a number of unique biological and pharmacological active compounds have been ascribed to various species of sea cucumbers. In current work the collagen peptides (CPs) from the bodies of the far-eastern holothurians (sea cucumber) Apostichopus japonicus and Cucumaria japonica by treated with a complex of proteolytic enzymes from Kamchatka crab Paralithodes camtschaticus were obtained, and the antitumor, anticoagulant, anti-inflammatory, and wound healing properties these CPs were estimated. The element and amino acid analysis of CPs from trepang and cucumaria are suggested that it’s could be regarded as a typical collagen fragments containing 6% sulfated carbohydrate and/or amino acid residues. CPs inhibited growth and progression solid Erlich tumor, but not in alike degree. Our results clearly showed, that these CPs possessed the moderate anticoagulant activity, and are preferential inhibitors of the initial link of the blood coagulation system. We also determined that the CPs revealed significant wound healing effect in regarding to thermal wounds and have high anti-inflammatory activity by used carrageenane model of acute inflammatory. Apparently, that the degree of biological activity depend on characteristics of amino acid composition and concentration of CPs. Taken together, these results indicate that CPs from sea cucumbers have similar to biological activities with other collagen peptides (components of the extracellular matrix, endostatin and others) and sulfated polysaccharides. We proposed that the obtained CPs may be applied as components functional food and nontoxic remedies of supplementary therapy for prevention and treatment of various diseases.

Adaptation to cold of homeothermic organism: changes in afferent and efferent links of the thermoregulatory system

This review focuses on mechanisms of cold adaptation and with the interaction of the afferent and efferent links of the system of thermal homeostasis found through major research advances in our department. Certain mechanisms of adaptive changes in metabolic and heat loss processes were disclosed mostly concentrated on muscle and respiratory functions. It was shown that, as a result of cold adaptation, there occur changes in the functional characteristics of the central and peripheral thermoreceptors, which form the input signal and determine the regulatory parameters of the system of thermal homeostasis. The adaptive changes in the afferent link are consistent also with the re-arrangement in the work of the respiratory system. The accumulated facts give grounds for believing that the important role of thermoreceptors in maintenance of adaptive re-arrangement is due to the direct and feedback relation to the neurohumoral systems of the organism. The direct relation makes possible the implementation of a wide range of effector responses to thermal stimulus; while the feedback relation makes possible various modulations of the thermoreceptors, which are the initial link of the thermoregulatory system.

How Should Debriefing Be Undertaken in Web-Based Studies? Findings From a Randomized Controlled Trial

BackgroundInternet research may raise older ethical issues in new forms or pose new issues. It has been recommended that debriefing information online be kept very short, with further information including study results made available if requested by participants. There are no empirical studies that compare possible alternative methods of debriefing in online studies.ObjectiveTo undertake a randomized controlled trial evaluating how to implement the recommended approach by assessing the effects of two different approaches on accessing of additional information.MethodsAll 11,943 participants in the Effects of Study Design and Allocation (ESDA) study, which employed deception, were randomly assigned to one of two methods of debriefing: Group A received the debriefing information in the body of an email with links to protocol and results pages; Group B was presented with these links after clicking on an initial link in the body of the email to view the debriefing information on a website. Outcomes assessed were the proportions clicking on the links to the protocol and results summary and the time spent on these pages by those accessing them.ResultsThe group who were presented with no debriefing information in the body of the email and went to a website for this information (Group B) were approximately twice as likely to subsequently access the protocol and the results summary. These differences between the two groups were highly statistically significant. Although these differences are clear, the overall proportions accessing such information were low, and there were no differences in mean time spent reading these pages. Only one quarter of Group B actually accessed debriefing information.ConclusionsIn circumstances where the uptake of fuller information on study design, methods, and findings is deemed important, debriefing information may be better provided via a link and not included in the body of an email. Doing so may, however, reduce the extent of receiving any debriefing information at all. There is a wider need for high quality empirical studies to inform ethical evaluations.Trial RegistrationAustralian New Zealand Clinical Trials Registry, ACTRN12610000846022 (http://www.anzctr.org.au/)

The effect of aerobic soil conditions, soil volume and sowing date on the development of four tropical rice varieties grown in the greenhouse.

Rice has generally been reported to yield less in aerobic soil conditions than in flooded soil conditions, in association with delayed anthesis and a reduction in height. A greenhouse experiment was conducted and repeated twice with four rice varieties grown in either flooded or nearly-saturated aerobic soil, in either large or small pots. The rate of leaf appearance was recorded weekly until heading time, when plants were harvested for shoot and root biomass. The kinetics of leaf appearance was generally trilinear with longer phyllochrons in the May sowing. Pot size had only a small effect whereas aerobic soil conditions slowed down the rate of leaf initiation, which consequently delayed panicle initiation and heading date and thus increased the duration of the tillering phase and finally the number of tillers. Surprisingly, the four varieties showed a significant response to sowing date, especially IR72, which headed 21 days later and after the expansion of two more leaves in the May sowing. The aerobic soil conditions and sowing date have thus changed the rate of development of rice plants and this trait has appeared to be the initial link of a chain of consequences in a series of traits known to be affected by these factors.

Canonical correlation analysis of synchronous neural interactions and cognitive deficits in Alzheimer's dementia

In previous work (Georgopoulos et al 2007 J. Neural Eng. 4 349–55) we reported on the use of magnetoencephalographic (MEG) synchronous neural interactions (SNI) as a functional biomarker in Alzheimer's dementia (AD) diagnosis. Here we report on the application of canonical correlation analysis to investigate the relations between SNI and cognitive neuropsychological (NP) domains in AD patients. First, we performed individual correlations between each SNI and each NP, which provided an initial link between SNI and specific cognitive tests. Next, we performed factor analysis on each set, followed by a canonical correlation analysis between the derived SNI and NP factors. This last analysis optimally associated the entire MEG signal with cognitive function. The results revealed that SNI as a whole were mostly associated with memory and language, and, slightly less, executive function, processing speed and visuospatial abilities, thus differentiating functions subserved by the frontoparietal and the temporal cortices. These findings provide a direct interpretation of the information carried by the SNI and set the basis for identifying specific neural disease phenotypes according to cognitive deficits.

Resistance to change and preference for variable versus fixed response sequences.

In Experiment 1, 4 pigeons were trained on a multiple chain schedule in which the initial link was a variable-interval (VI) 20-s schedule signalled by a red or green center key, and terminal links required four responses made to the left (L) and/or right (R) keys. In the REPEAT component, signalled by red keylights, only LRLR terminal-link response sequences were reinforced, while in the VARY component, signalled by green keylights, terminal-link response sequences were reinforced if they satisfied a variability criterion. The reinforcer rate for both components was equated by adjusting the reinforcer probability for correct REPEAT sequences across sessions. Results showed that initial- and terminal-link responding in the VARY component was generally more resistant to prefeeding, extinction, and response-independent food than responding in the REPEAT component. In Experiment 2, the REPEAT and VARY contingencies were arranged as terminal links of a concurrent chain and the relative reinforcer rate was manipulated across conditions. For all pigeons, initial-link response allocation was biased toward the alternative associated with the VARY terminal link. These results replicate previous reports that operant variation is more resistant to change than operant repetition (Doughty & Lattal, 2001), and show that variation is preferred to repetition with reinforcer-related variables controlled. Behavioral momentum theory (Nevin & Grace, 2000) predicts the covariation of preference and resistance to change in Experiments 1 and 2, but does not explain why these aspects of behavior should depend on contingencies that require repetition or variation.

Research on Evolution and Synchronization of Space Information Support Power Networks

The evolution and synchronization of the space information support network was discussed based on the theories of Networks Science. A network model of the architecture was established and the characteristic parameters of this model and the synchronization foundation were studied. The effect of the initial link mechanism, the number of communication nodes, other information support nodes and the total nodes on the evolution and synchronization of this network were analyzed. Simulation results show that the models and the method are erective and scientific．The research can be some reference value to the further study of related problems.

A Functional Communication Training and Chained Schedule Procedure to Treat Challenging Behavior with Multiple Functions

We evaluated a procedure consisting of functional communication training (FCT) and a chained schedule of reinforcement to treat multiply maintained challenging behavior exhibited by an individual diagnosed with autism. First, we conducted a functional analysis that yielded results indicating that challenging behavior served multiple functions. Next, we implemented a chained schedule of reinforcement procedure in which during the initial link, mands for a stimulus were reinforced on a fixed ratio (FR) 1 schedule of reinforcement. The participant’s access to the stimulus signaled the second link of the chained schedule that consisted of a fixed time (FT) 30 s schedule in which all three functional reinforcers were provided. Last, we modified the chained schedule procedure to increase ease of implementation and promote compliance with academic tasks. The results showed that the treatment was successful in the treatment of challenging behavior with multiple functions. Future directions in the development of treatments that simultaneously address multiple functions are discussed.

Mortality in Coronary Artery Bypass Grafting

Over the past 48 years, coronary artery bypass grafting (CABG) has been among the most studied procedures in all of medicine. In part, this has been because CABG is a high-volume, high-cost intervention for ischemic heart disease. But, in addition to this, CABG is associated with an easily identifiable outcome that occurs with sufficient frequency to be of substantial interest to both providers and patients, namely, procedural mortality. The initial link between CABG and mortality was from the left main coronary artery subset of the Coronary Artery Surgery Study (CASS), which interestingly only included 150 patients.1 Article see p 2423 The development and widespread adoption of the Society of Thoracic Surgeons National Adult Database,2 the Northern New England Consortium,3 and other regional databases such as the New York State Cardiac Surgery Reporting System (CSRS),4 Michigan Society of Thoracic Surgeons,5 and Virginia Cardiac Surgery Quality Initiative6 have provided major refinements to our understanding of the impact of coronary bypass grafting on short-term (in-hospital and/or 30-day) mortality. Over the past 20 years, the risk-adjusted (RA) mortality related to CABG has declined, through a combination of process improvement2,7,8 and regional and national system intervention.3–6 According to the Society of Thoracic Surgeons National Database 2008 risk model, the short-term RA mortality for CABG has been oscillating at ≈2% for the past 3 years.9 The weight of importance of short-term RA mortality as an outcome for CABG is reflected in its use as a National Quality Forum quality metric,10 in ranking hospital performance,11 and in public reporting.12 However, closer inspection of these Society of Thoracic Surgeons data demonstrate that over the …

Marine plants in a coral reef ecosystem

Based on a review of the literature and our own data, marine plants are shown to play an important role in the formation and sustaining of coral reefs, which are one of coastal tropical ecosystems of the World Ocean. The important ecosystem roles of marine plants include primary production and recycling of organic matter, the construction of the hard base of a coral reef, the fixation of dissolved molecular nitrogen in sea-water, the formation of an initial link in the food chain, the provision of a habitat for marine animals, and the protection of the reef against destructive wave action.

PREFERÊNCIA POR LIBERDADE DE ESCOLHA MESMO QUANDO UMA DAS ALTERNATIVAS NUNCA (OU RARAMENTE) É ESCOLHIDA

Em uma situação de liberdade de escolha (escolha livre), duas ou mais respostas elegíveis para reforço estão concorrentemente disponíveis, como quando as bicadas de um pombo em qualquer um de dois discos pode produzir reforços em intervalo-fixo (FI). Em escolha forçada, uma única resposta é elegível para reforço, como quando as bicadas em um disco podem produzir reforços em FI, mas as bicadas em um segundo disco são colocadas em extinção (EXT).A liberdade de escolha tem sido tipicamente preferida à escolha forçada, quando ambas constituem os elos terminais de esquemas encadeados concorrentes ou de esquemas múltiplos encadeados concorrentes. Quando esquemas múltiplos encadeados concorrentes programam as condições A e B para os elos terminais à esquerda e à direita, respectivamente, na presença de um dos estímulos do elo inicial, mas programam as posições inversas para A e B nos elos terminais na presença do outro estímulo do elo inicial, as preferências podem ser determinadas, ao longo das sessões, como diferenças nas taxas relativas nos elos iniciais. A questão neste experimento era se a preferência por escolha livre é demonstrável mesmo quando uma das alternativas quase nunca é escolhida ou é escolhida raramente. Uma história experimental sob esquemas múltiplos cujos componentes eram cadeias concorrentes, nas quais os elos terminais eram um mesmo esquema de FI, foi seguida pelo treino, independente dos elos iniciais, de FI 20-s (disco verde), FI 40-s (disco amarelo), e EXT (disco vermelho) nos elos terminais. Então, os esquemas múltiplos de cadeias concorrentes programaram os elos terminais de escolha livre com dois discos, verde (FI 20-s) e amarelo (FI 40-s), concorrentemente com elos terminais de scolha forçada, também com dois discos, um verde (FI 20-s) e outro vermelho (EXT). Esses elos terminais mantiveram o responder quase que exclusivamente no disco verde, quer o outro fosse amarelo ou vermelho, e todos os reforços foram produzidos por respostas no disco verde. Embora os reforços fossem iguais e a alternativa com o disco amarelo nunca ou quase nunca tivesse sido escolhida, o elo terminal com os discos verde e amarelo (escolha livre) foi preferido ao elo terminal com os discos verde e vermelho (escolha forçada).Palavras-chave: escolha livre, escolha forçada, preferência, esquemas encadeados concorrentes, elos iniciais, elosterminais, operantes discriminados

The Mathematical Structure of Information Bottleneck Methods

Information Bottleneck-based methods use mutual information as a distortion function in order to extract relevant details about the structure of a complex system by compression. One of the approaches used to generate optimal compressed representations is by annealing a parameter. In this manuscript we present a common framework for the study of annealing in information distortion problems. We identify features that should be common to any annealing optimization problem. The main mathematical tools that we use come from the analysis of dynamical systems in the presence of symmetry (equivariant bifurcation theory). Through the compression problem, we make connections to the world of combinatorial optimization and pattern recognition. The two approaches use very different vocabularies and consider different problems to be “interesting”. We provide an initial link, through the Normalized Cut Problem, where the two disciplines can exchange tools and ideas.

La reflexividad en los procesos organizativos juveniles

This article reconstructs the intellectual network that surrounded the edition and publication of Espiral de Artes y Letras a magazine founded in Bogotá by the Spanish exile Clemente Airó in 1944. It begins by considering the analysis of the magazine with a focus on intellectual networks, and aims to explain how the expansion of connections, from the initial links to the Colombian intellectual field to the Hispanic American scene, became a key strategy for sustaining one of the longest-living cultural projects of the country.

CONCURRENT‐CHAINS SCHEDULES AS A METHOD TO STUDY CHOICE BETWEEN ALCOHOL‐ASSOCIATED CONDITIONED REINFORCERS

An extensive body of research using concurrent-chains schedules of reinforcement has shown that choice for one of two differentially valued food-associated stimuli is dependent upon the overall temporal context in which those stimuli are embedded. The present experiments examined whether the concurrent chains procedure was useful for the study of behavior maintained by alcohol and alcohol-associated stimuli. In Experiment 1, rats responded on concurrent-chains schedules with equal variable-interval (VI) 10-s schedules in the initial links. Across conditions, fixed-interval schedules in the terminal links were varied to yield 1∶1, 9∶1, and 1∶9 ratios of alcohol delivery. Initial-link response rates reflected changes in terminal-link schedules, with greater relative responding in the rich terminal link. In Experiment 2, terminal-link schedules remained constant with a 9∶1 ratio of alcohol delivery rates while the length of two equal duration initial-link schedules was varied. Preference for the rich terminal link was less extreme when initial links were longer (i.e., the initial-link effect), as has been previously reported with food reinforcers. This result suggests that the conditioned reinforcing value of an alcohol-associated stimulus depends on the temporal context in which it is embedded. The concurrent-chains procedure and quantitative models of concurrent chains performance may provide a useful framework within which to study how contextual variables modulate preference for drug-associated conditioned reinforcers.

Immunonutrition in Early Life: Diet and Immune Development

The belief that “you are what you eat” originated from Brillat-Savarin et al. (“tell me what you eat, and I will tell you who you are”) in the 1800s [1] was the starting point in the quest to understand the role of diet in almost every function in the body and in overall health. However, prior to the 1950s, there was little recognition of the relationship between nutrition and immune function. Scrimshaw and colleagues first described the bidirectional interaction between nutrition and infection [2]. This initial link between malnutrition and infective diseases has since evolved; not only do we now consider that diet is critical in maintaining optimal immune function, but it is widely accepted that almost all nutrients in the diet play a crucial role in maintaining an “optimal” immune response, and that both deficiency and excessive intakes can have negative consequences in terms of immune status and susceptibility to a variety of pathogens [3]. Dietary components with immunomodulatory potential include vitamins, minerals, polyphenols, dietary polyunsaturated fatty acids (PUFAs), and dietary components with the ability of modulating the gut microbiota (fibre, prebiotics, and probiotics). Although extensive research (experimental and clinical) demonstrates the properties of some of these dietary components, in many cases the exact mechanisms remain unclear. The impact of particular nutrients has been investigated by both epidemiological and intervention studies, but there are relatively few studies dealing with immune development in early life and in subjects with common immune-mediated diseases in early life (coeliac disease or asthma/allergies).

TEMPORAL CONTEXT, PREFERENCE, AND RESISTANCE TO CHANGE

According to behavioral momentum theory, preference and relative resistance to change in concurrent-chains schedules are correlated and reflect the relative conditioned value of discriminative stimuli. In the present study, we explore the generality of this relation by manipulating the temporal context within a concurrent-chains procedure through changes in the duration of the initial links. Consistent with previous findings, preference for a richer terminal link was less extreme with longer initial links across three experiments with pigeons. In Experiment 1, relative resistance to change and preference were related inversely when responding was disrupted with response-independent food presentations during initial links, replicating a previous finding with rats. However, more food was presented with longer initial links, confounding the disrupter and initial-link duration. In Experiment 2, presession feeding was used instead and eliminated the negative relation between relative resistance to change and preference, but relative resistance to change was not sensitive to relative terminal-link reinforcement rates. In Experiment 3, with more extreme relative terminal-link reinforcement rates, increasing initial-link duration similarly decreased preference and relative resistance to change for the richer terminal link. Thus, when conditions of disruption are equal and assessed under the appropriate reinforcement conditions, changes in temporal context impact relative resistance to change and preference similarly.

OSPF failure reconvergence through SRG inference and prediction of link state advertisements

We demonstrate machine learning augmented Open Shortest Path First (OSPF) routing which infers Shared Risk Groups (SRG) from link failure history. For an initial link failure matching an SRG, it predicts subsequent link state advertisements corresponding with that SRG, improving convergence and recovery times during multiple network failures.

Antitumor and anticoagulant activities of collagen protein from the holothurian Apostichopus japonicas modified by proteolytic enzymes

A collagen preparation with antitumor and anticoagulant activity was obtained from the body of the holothurian (sea cucumber) Apostichopus japonicus treated with a complex of proteolytic enzymes. Administration of the collagen preparation inhibited in vivo growth of Ehrlich solid adenocarcinoma 2-fold (P < 0.05) and contributed to the survival of ascitic tumor-bearing mice, increasing their life span by 29.4 ± 3.2% (P < 0.05). With its moderate anticoagulant activity, this preparation is a preferential inhibitor of the initial link of the blood coagulation system. The biomedical properties and the character of the chemical structure of the collagen protein obtained from A. japonicus suggest that the mechanism of its action is similar to that of the collagen-like protein endostatin and sulfated polysaccharides. The obtained protein may be applied as a nontoxic agent of supplementary therapy for oncological and cardiovascular diseases.

Further evaluation of prompting tactics for establishing intraverbal responding in children with autism.

We compared prompting tactics to establish intraverbal responding (question answering) in four boys with autism. Based on the results of intraverbal, textual, echoic, and tact pretests, we compared vocal and picture prompts with three participants, and textual, vocal, and picture prompts with one participant. We also evaluated repeated acquisition with different question sets, and included a concurrent-chains arrangement, in which initial link selections determined which prompting procedure occurred in the terminal link. All the prompting procedures were effective in establishing intraverbal responding, but vocal prompts resulted in the fewest trials to criterion for all four participants during the initial prompt comparison. However, the results were less consistent for the second comparison. The concurrent chains arrangement revealed a clear preference for picture prompts for one participant, but the results for the others were inconclusive.

Motivational control of impulsive behavior interacts with choice opportunities

Impulsive behavior has been investigated through choice between a smaller/immediate reinforcer and a larger/delayed reinforcer, or through performance on a differential reinforcement of low rate (DRL) schedule. In the present study, we investigated a methodological divergence between these two procedures: in the former procedure, delay is a consequence of the subject's own choice, whereas in the later procedure, subjects are explicitly reinforced for delaying a response. In Experiment 1, 7 rats maintained at 80% of their free-feeding weights showed poorer efficiency of lever-pressing responses on a DRL 30-s schedule than when they were maintained at 90% of free-feeding weight. In Experiment 2, 16 rats were subjected to a concurrent chain schedule: the initial link was concurrent fixed ratio 1 fixed ratio 1, and each of these alternatives was followed by a short-DRL requirement with a one pellet reinforcer or a long-DRL requirement with a three pellet reinforcer. In one block of trials, rats were not allowed to choose between the two terminal links (forced-choice), whereas in the other block of trials rats were allowed to choose freely between the two terminal links (free-choice). Compared with rats maintained at 95% of their free-feeding weights, rats maintained at 80% of their free-feeding weights showed poorer efficiency in the terminal links’ DRL schedule performance (just as in Experiment 1), but this difference was shown only in the forced-choice blocks. These results indicate that motivational control of DRL schedule performance interacts with type of choice-making opportunity and highlight the direct comparison of motivational control of impulsive choice and DRL schedule performance.