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1.
Matching analysis has often attracted the criticism that it is formally tautological and hence empirically unfalsifiable, a problem that particularly affects translational attempts to extend behavior analysis into new areas. An example is consumer behavior analysis where application of matching in natural settings requires the inference of ratio-based relationships between amount purchased and amount spent. This gives rise to the argument that matching is an artifact of the way in which the alleged independent and dependent variables are defined and measured. We argue that the amount matching law would be tautological only in extreme circumstances (those in which prices or quantities move strictly in proportion); this is because of the presence of an error term in the matching function which arises from aggregation, particularly aggregation over brands. Cost matching is a viable complement of amount matching which avoids this tautology but a complete explanation of consumer choice requires a viable measure of amount matching also. This necessitates a more general solution to the problem of tautology in matching. In general, the fact that there remain doubts about the functional form of the matching equation itself implies the absence of a tautology. In proposing a general solution to the problem of assumed tautology in matching, the paper notes the experiences of matching researchers in another translation field, sports behavior.  相似文献   

2.
Twelve female Long-Evans rats were exposed to concurrent variable (VR) ratio schedules of sucrose and wheel-running reinforcement (Sucrose VR 10 Wheel VR 10; Sucrose VR 5 Wheel VR 20; Sucrose VR 20 Wheel VR 5) with predetermined budgets (number of responses). The allocation of lever pressing to the sucrose and wheel-running alternatives was assessed at high and low body weights. Results showed that wheel-running rate and lever-pressing rates for sucrose and wheel running increased, but the choice of wheel running decreased at the low body weight. A regression analysis of relative consumption as a function of relative price showed that consumption shifted toward sucrose and interacted with price differences in a manner consistent with increased substitutability. Demand curves showed that demand for sucrose became less elastic while demand for wheel running became more elastic at the low body weight. These findings reflect an increase in the difference in relative value of sucrose and wheel running as body weight decreased. Discussion focuses on the limitations of response rates as measures of reinforcement value. In addition, we address the commonalities between matching and demand curve equations for the analysis of changes in relative reinforcement value.  相似文献   

3.
Behavioral economics is useful for understanding the influence of environmental manipulation on a variety of behaviors, including drug self-administration, food intake, and stock behavior. The present study employed behavioral economics to investigate the psychologically satisfying amount of water intake in a laboratory rhesus macaque. Our institutional guidelines set a minimum amount of daily water intake. However, no study to date has determined whether that minimum amount is psychologically sufficient. In the present experiment, a monkey lived in an individual cage in which the only water available was delivered by chain pulling. A fixed number of responses was required for water delivery. This fixed ratio (FR) of responses per water delivery was progressively increased from FR 2 to FR 10. The study findings showed that during the FR 2 condition, demand for water was saturated at 131.3 ml/kg body weight (BW) (ranging from 95.1 to 211.2). The monkeys daily intake of water decreased as FR size incrementally increased, approaching an asymptote under the FR 8 and FR 10 conditions. During the FR 8 and FR 10 conditions, responding ceased when this monkey earned 53.5 ml/kg-BW (ranging from 32.7 to 74.9) of water. Therefore, the amount of water obtained under these conditions might provide a psychologically satisfying amount. Although these values were obtained from the behavioral study of one monkey, they were almost equivalent to values in our institutional guidelines that were determined by veterinary observations. These findings imply that behavioral economics is useful for studying the welfare of laboratory animals.  相似文献   

4.
The neurosciences embrace many disciplines, some long established, others of more recent origin. Behavioral endocrinology has only recently been fully acknowledged as a branch of neuroscience, distinctive for the determination of some of its exponents to remain integrative in the face of the many pressures towards reductionism that so dominate modern biology. One of its most characteristic features is a commitment to research at the whole-animal level on the physiological basis of complex behaviors, with a particular but by no means exclusive focus on reproductive behavior in all its aspects. The search for rigorously defined principles of behavioral organization that apply across species and the hormonal and neural mechanisms that sustain them underlies much of the research. Their aims are much like those put forth in the classical ethology of Lorenz and Tinbergen, one of the roots from which behavioral endocrinology has sprung. But there are others that can be traced back a century or more. Antecedents can be found in the work of such pioneers as Jakob von Uexküll, Jacques Loeb, Herbert Spencer Jennings, and particularly Charles Otis Whitman who launched a tradition that culminated in the classical contributions of Robert Hinde and Daniel Lehrman. William C. Young was another pioneer. His studies revolutionized thinking about the physiological mechanisms by which hormones influence behavior. An earlier potent influence was Karl Lashley who helped to shape the career of Frank Ambrose Beach who, more than anyone, has played a leading role in launching this new field.  相似文献   

5.
Efforts to understand cognition will be greatly facilitated by computerized systems that enable the automated analysis of animal behavior. A number of controversies in the invertebrate learning field have resulted from difficulties inherent in manual experiments. Driven by the necessity to overcome these problems during investigation of neural function in planarian flatworms and frog larvae, we designed and developed a prototype for an inexpensive, flexible system that enables automated control and analysis of behavior and learning. Applicable to a variety of small animals such as flatworms and zebrafish, this system allows automated analysis of innate behavior, as well as of learning and memory in a plethora of conditioning paradigms. We present here the schematics of a basic prototype, which overcomes experimenter effects and operator tedium, enabling a large number of animals to be analyzed with transparent on‐line access to primary data. A scaled‐up version of this technology represents an efficient methodology to screen pharmacological and genetic libraries for novel neuroactive reagents of basic and biomedical relevance. © 2006 Wiley Periodicals, Inc. J Neurobiol, 2006  相似文献   

6.
We develop fractional allocation models and confidence statistics for parentage analysis in mating systems. The models can be used, for example, to estimate the paternities of candidate males when the genetic mother is known or to calculate the parentage of candidate parent pairs when neither is known. The models do not require two implicit assumptions made by previous models, assumptions that are potentially erroneous. First, we provide formulas to calculate the expected parentage, as opposed to using a maximum likelihood algorithm to calculate the most likely parentage. The expected parentage is superior as it does not assume a symmetrical probability distribution of parentage and therefore, unlike the most likely parentage, will be unbiased. Second, we provide a mathematical framework for incorporating additional biological data to estimate the prior probability distribution of parentage. This additional biological data might include behavioral observations during mating or morphological measurements known to correlate with parentage. The value of multiple sources of information is increased accuracy of the estimates. We show that when the prior probability of parentage is known, and the expected parentage is calculated, fractional allocation provides unbiased estimates of the variance in reproductive success, thereby correcting a problem that has previously plagued parentage analyses. We also develop formulas to calculate the confidence interval in the parentage estimates, thus enabling the assessment of precision. These confidence statistics have not previously been available for fractional models. We demonstrate our models with several biological examples based on data from two fish species that we study, coho salmon (Oncorhychus kisutch) and bluegill sunfish (Lepomis macrochirus). In coho, multiple males compete to fertilize a single female's eggs. We show how behavioral observations taken during spawning can be combined with genetic data to provide an accurate calculation of each male's paternity. In bluegill, multiple males and multiple females may mate in a single nest. For a nest, we calculate the fertilization success and the 95% confidence interval of each candidate parent pair.  相似文献   

7.
Reliable estimates of life history parameters and their functional role in animal population trajectories are critical, yet often missing, components in conservation and management. We developed seasonal matrix population models of the Red‐tailed Hawk Buteo jamaicensis jamaicensis in the upper and lower forests of the Luquillo Mountains, Puerto Rico, to describe the influence of early life stages (nestling and clutch survival) on population growth. Modelled populations exhibited positive discrete rates of growth in forests above 400 m (λ highlands = 1.05) and in forests below 400 m (λ lowlands = 1.27) of the Luquillo Mountains. Further, adult survival was the parameter with the highest proportional effect and direct contribution to growth of the population. Besides survival of adults, our results identified that nestling survival had the second greatest influence on λ, stressing the importance of this life stage for the population growth rate of Red‐tailed Hawks in our study area. Seasonal matrices are not commonly used to describe population dynamics of birds. However, these may be a useful tool to analyse the influence of life stages in the annual cycle to better address conservation and management needs, especially for species inhabiting oceanic islands.  相似文献   

8.
The objective of this work was to study the effect of early weaning on circadian rhythm and the behavioral satiety sequence in adult rats. Male Wistar rat pups were weaned for separation from the mother at 15 (D15), 21 (D21) and 30 (D30) days old. Body weight and food intake was measured every 30 days until pups were 150 days old. At 90 days of age, the circadian rhythm of food intake was evaluated every 4 h for three days. Behavioral satiety was evaluated at 35 and 100 days of age. This work demonstrated that body weight and food intake were not altered, but the behavioral satiety sequence demonstrated that the D15 group delayed satiety compared with the D30 group at 100 days of age. In the circadian rhythm of the food intake study, early weaning (D15) changed food intake in the intermediary period of the light phase and in the intermediary period of the dark phase. In conclusion, our study showed that early weaning may alter the feeding behavior mainly in relation to satiety and the circadian rhythm of feeding. It is possible that the presence of other environmental stimuli during early weaning can cause hyperphagia and deregulate the mechanisms of homeostasis and body weight control. This study supports theories that depict insults during early life as determinants of chronic diseases.  相似文献   

9.
Assessing voice quality objectively is of great relevance to clinicians, both for quantifying surgical or pharmacological effectiveness and for detecting and classifying voice pathology. A large number of objective indexes have been proposed in literature and implemented in commercially available software tools. However, clinicians commonly resort to a small subset of these indexes since they may be difficult to set up or understand.This paper presents a new user-friendly voice analysis tool named BioVoice. At present, BioVoice allows for the evaluation of few but important indexes, devoting great effort to their robust and automatic evaluation, although extensions are foreseeable. Specifically, fundamental frequency, along with irregularity (jitter, relative average perturbation), noise, and formant frequencies, is tracked on voiced parts of the signal only. Mean and standard deviation values are also calculated and displayed. This high-resolution estimation procedure is further strengthened by an adaptive estimation of the optimal length of signal frames for analysis, linked to varying signal characteristics.Moreover, BioVoice allows automatic analysis of any kind of voice signal as far as F0 range and sampling frequency are concerned, with no manual setting required. This new tool is thus feasible for use by non-experts from different scientific fields, thanks to its simple interface.Here, the proposed approach is applied to patients who underwent micro-laryngoscopic direct exeresis to remove cysts and polyps. Pre- and post-surgical indexes were estimated using BioVoice and then compared with the output of one of the most common commercial software tools to both assess voice quality recovery and to evaluate the new method’s capabilities.  相似文献   

10.
The social behavior of male stumptail macaques was analyzed in terms of behavioral sequences recorded during paired encounters in a large test cage. Recurrent patterns of behavioral sequences were sought and used to hypothesize the structure of motivational systems of social behavior as has been done previously for other species. In addition to traditional statistical analyses to determine which dyadic behavioral sequences were nonrandom, there were several methodological innovations. Instead of analyzing behavior as a single channel of communications, we analyzed three independent channels and considered their inter-correlations: 1) acts and postures; 2) vocalizations; and 3) facial expressions. Also, we analyzed not only within-animal behavioral sequences but between-animal sequences as well. Results were derived from 40 tests, most of which included vigorous agonistic and sexual interactions and a behavioral repertoire similar to that of adult male stumptail macaques observed by previous investigators. There were 30 acts and postures, eight facial expressions, and seven vocalizations that occurred more than five times. Many acts and postures occurred in nonrandom sequences, 43 such sequences within-animal and 40 between-animal. From these sequences and their correlations with specific vocalizations and facial expressions, it was possible to differentiate six categories of social behavior that may correspond to six different motivational systems: offense, defense, submission, groom and contact, male sexual behavior, and display. Both the frequency of behaviors in each category and the nature of the behavioral sequences were affected by the relative dominance of the two animals.  相似文献   

11.
Metabolic control analysis of plant metabolism   总被引:11,自引:1,他引:11  
Metabolic control analysis and its major coefficients are introduced. The importance of measuring both elasticity and concentration-control coefficients as well as flux-control coefficients is stressed. The conditions that need to be met before control analysis can be applied experimentally are emphasized. It is argued that successful application of this approach requires methods for the measurement of flux, maximum catalytic activities of enzymes and substrate contents. The measurement of flux by consumption of substrate, production of product, and the distribution of isotope after metabolism of labelled substrates is discussed. The need to ensure that measurements of enzymes and substrates are reliable and authenticated is stressed. Particular emphasis is placed on the ease with which such measurements can be invalidated in plant tissues, and ways for countering these difficulties are discussed.  相似文献   

12.
基于广西北部湾经济区4城市940位受访者的问卷调查结果,采用 logit模型对这些受访者保护滨海优良生态环境的最大支付意愿(WTP)和接受的最小赔偿意愿(WTA)进行了测算,其结果显示:5年内的WTP期望值为450.17元 a-1-1, WTA期望值为5772.71元 a-1-1,WTA/WTP比值为12.8倍,表现出非常明显的非对称性特征,但基本符合国内外在该领域的实证结果。通过对同一受访者支付意愿和接受赔偿意愿的交叉分析,可知WTP和WTA同时不为0的受访者有276人,占总抽样人次的29.4%,其WTA/WTP比值为12.54,与logit模型测算的WTA/WTP比值非常接近,从一侧面更准确地反映了这一群体对环境物品估值的差异性,同时也可反映logit模型测算的可靠性。基于行为经济学的前景理论分析,发现研究中的受访者存在厌恶损失效应、框架效应和对预期不确定风险的规避行为,同时受访者还存在明显的搭便车行为。通过对受访者的情境因素分析,发现其中2个情境因素对受访者选择WTP和WTA具有较大影响,主要表现为惩罚效应,尤其是经济收入满意度情境因素对受访者的经济行为影响显著,而另3个情境因素未表现出有规律性的影响。  相似文献   

13.
Several aspects of locomotor control have been ascribed to the central complex of the insect brain; however, the role of distinct substructures of this complex is not well known. The tay bridge1 (tay1) mutant of Drosophila melanogaster was originally isolated on the basis of reduced walking speed and activity. In addition, tay1 is defective in the compensation of rotatory stimuli during walking and histologically, tay1 causes a mid-sagittal constriction of the protocerebral bridge, a constituent of the central complex. Cloning of the tay gene revealed that it encodes a novel protein with no significant homology to any known protein. To associate the behavioral phenotypes with the anatomical defect in the protocerebral bridge, we used different driver lines to express the tay cDNA in various neuronal subpopulations of the central brain in tay1-mutant flies. These experiments showed an association of the aberrant walking speed and activity with the structural defect in the protocerebral bridge. In contrast, the compensation of rotatory stimuli during walking was rescued without a restoration of the protocerebral bridge. The results of our differential rescue approach are supported by neuronal silencing experiments using conditional tetanus toxin expression in the same subset of neurons. These findings show for the first time that the walking speed and activity is controlled by different substructures of the central brain than the compensatory locomotion for rotatory stimuli.  相似文献   

14.
While a large body of literature exists on the ability of biochar to retain water and nutrients, little research exists connecting these benefits to biochar qualities, water retention mechanisms, and optimal locations for agricultural use. More information is needed for biochar stakeholders to make informed decisions about where deployment should occur. Specifically, we need to know the biochar characteristics that drive changes in soil water properties, how these effects vary geographically, and what financial benefits farmers can expect in their specific region to identify where biochar can be deployed for optimal results. We conducted a meta‐analysis of the relationship between biochar properties, application rates and observed change in water holding capacity (WHC) as a function of soil texture. Then we mapped our results across US counties to determine where biochar application could yield the largest improvements in soil water properties and added an economic model designed to predict how biochar‐driven changes in soil WHC drive irrigation expenses. Limited data drove our focus to sandy soils, and among these locations, our results suggest that biochar application will be especially effective in the southeast, far north and northeast, and western United States. In a prototype application of our model we predict a 37% reduction in irrigated water use for an instrumented site in Nebraska. Our combined statistical and economic models will be useful for future field experiment proposals, farmers purchasing biochar, and decision makers working to incentivize agricultural advances.  相似文献   

15.
Introduction – Matrix solid‐phase dispersion (MSPD) is a very simple, cheap and relatively quick sample preparation procedure which involves simultaneous disruption and extraction of various solid and semi‐solid samples due to the direct mechanical blending of the sample with a SPE sorbent, mainly C18. Little is known about MSPD application as a sample preparation method for the analysis of essential oil components in herbs. Objective – To evaluate if C18 sorbent, commonly used in MSPD process, can be substituted with sand in the procedure of essential oil analysis. Methodology – Essential oil extracts were obtained from mint, sage, chamomile, marjoram, savory and oregano using MSPD with C18 sorbent or sand, pressurised liquid extraction and steam distillation. Their qualitative and quantitative compositions ware established by GC‐MS and GC‐FID. Results – The results prove that C18 sorbent can be substituted with sand in the procedure of essential oil analysis in herbs. The recoveries of essential oil components estimated using MSPD/sand are almost equal to those using pressurised liquid extraction. Conclusion – The results presented in the paper reveal that MSPD with sand is suitable for the isolation of essential oil components from herbs. Its extraction efficiency is equivalent to pressurised liquid extraction, recognised as one of the most efficient extraction methods. The cost of MSPD procedure for essential oil analysis can be significantly diminished by substituting C18 with sand. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

16.
绿洲是干旱区特有的生态系统,而农田生态系统的数量和质量的变化很大程度上决定着绿洲的变化,进而影响到区域社会经济的可持续发展。以西北干旱区典型绿洲--民勤绿洲为例,采用生态经济学的方法,对民勤绿洲2000-2009年近10年的农田生态系统服务价值进行了定量计算及其驱动力分析,结果表明:民勤农田生态系统服务价值从2000年的3.21×108元逐年增加到2009年的6.95×108元,年均增长0.374×108元,其中,单纯生态系统服务价值年均增加约0.289×108元;社会保障功能价值每年保持在1.0×108元左右;使用化肥等导致农田环境污染,使得农田生态系统损失的价值由2000年的0.43×108元增加到2009年的0.64×108元;由于节水技术的采用,水资源利用效率的提高,农业耗水价值在不断减少,平均每年减少0.104×108元;采用资源紧缺度修正后的农田生态系统服务价值比原先都有所增加,但增幅不同,系每年水资源紧缺状况不同所致。采用多元回归分析法研究了人类活动对农田生态系统服务价值变化的影响,结果表明:民勤绿洲农田生态系统服务价值的这种变化是社会经济发展水平、农业管理水平、水资源利用、种植结构转变、以及人们的生态环保意识等多种因素共同驱动下的结果。  相似文献   

17.
18.
In order to investigate feeding synchronization in miniature pigs, a computer-controlled laboratory setup has been developed, recording the feeding behavior of two pigs at a time for weeks. Since, this setup delivers time series with a binary data structure, and thus Fourier-Spectral analysis is difficult to perform, Walsh - Fourier Spectral analysis for ordinal or binary data was utilized. Synchronicity between pigs housed together was estimated by coherency values, determined for the highest sequences of the Walsh - Fourier power spectra. Feeding behavior was recorded in 12 pigs (26 - 50 kg) housed in pairs, in separate, but adjacent pens. Pigs were conditioned to operate feeders and feeding was recorded for two weeks. Pigs housed adjacent to one another showed an overlap in the dominant sequencies which was confirmed by high corresponding coherency values. Furthermore, pairs of pigs were matched according to age, weight and gender, and combined by chance. Compared to these pairings, coherencies were higher and more consistent in pigs housed in adjacent pens. If the data structure is binary, Walsh - Fourier Spectral analysis utilizing coherencies as a measure of correlation between the spectra has been shown to be a useful tool in the investigation of behavioral synchronization.  相似文献   

19.
The traditional bulk elastic modulus approach to plant cell pressure-volume relations is inconsistent with its definition. The relationship between the bulk modulus and Young's modulus that forms the basis of their usual application to cell pressure-volume properties is demonstrated to be physically meaningless. The bulk modulus describes stress/strain relations of solid, homogeneous bodies undergoing small deformations, whereas the plant cell is best described as a thin-shelled, fluid-filled structure with a polymer base. Because cell walls possess a polymer structure, an alternative method of mechanical analysis is presented using polymer elasticity principles. This initial study presents the groundwork of polymer mechanics as would be applied to cell walls and discusses how the matrix and microfibrillar network induce nonlinear stress/strain relationships in the cell wall in response to turgor pressure. In subsequent studies, these concepts will be expanded to include anisotropic expansion as regulated by the microfibrillar network.  相似文献   

20.
Routine semen analysis includes evaluation of concentration combined with seminal volume, morphology and motility. Subjective analysis of these parameters is known to be inaccurate, imprecise and subject to variability. Automated semen analysis could lead to an increased standardization in and between laboratories but for that to happen automated devices need to be validated. A new device, the sperm quality analyzer V equine (SQA-Ve) version 1.00.43, was evaluated for its repeatability and agreement with light microscopy (LM), for raw and extended equine semen. Results were compared with computer assisted sperm analysis (CASA), which was also tested for its repeatability and agreement with LM. The SQA-Ve showed a good repeatability and fine agreement for assessing sperm concentration of raw semen based on scatter and Bland-Altman plots. This was in contrast with the motility parameters, which had a low repeatability. Morphology assessment with SQA-Ve was poorly repeatable as well as in poor agreement with LM. For extended semen, the findings were comparable. The SQA-Ve did well for concentration, whereas for the motility parameters repeatability was only just acceptable, with no agreement with LM. This sharply contrasted the CASA findings that were highly repeatable and almost in perfect agreement with LM. Based on these findings, the tested version of the SQA-Ve is insufficiently accurate to be used for analyzing raw or extended equine semen.  相似文献   

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