Serial Pattern Research Articles

Aggregate fluctuations, interest rates, and repeated insurance under private information

Using a linear-quadratic framework, I show (i) the formal equivalence of lending and optimal insurance when information about states is private, (ii) that lending equilibria induce the serial correlation patterns of aggregate and individual stochastic processes of consumption to be identical even if the corresponding income processes differ, (iii) the influence of the interest rate and the underlying serial correlation of the aggregate income process on potential insurance available in lending markets, (iv) the breakdown of individual rationality of the repeated private information contract and corresponding equilibria via defection to autarky. As an initial exploration of the force needed by an external mechanism that might prevent this defection, I analyze the average gain from defection, finding that the average gain from defection increases with the serial correlation of idiosyncratic income, associating defection with low interest rates.

Effects of prenatal alcohol exposure on serial pattern performance in the rat

The effect of prenatal alcohol exposure on serial-pattern learning was investigated in adult rats. Pregnant dams were administered a liquid diet which contained 35% ethanol-derived calories (35% EDC) on days 6–20 of gestation. Two control groups were included: a liquid diet control which was pair-fed and had sucrose substituted for ethanol (0% EDC); and a group fed standard lab chow throughout pregnancy. Offspring from each of these prenatal groups were trained to run a straight alley for food pellets. Pellet amount on successive trials was 14, 7, 3, 1, 7. Subjects were exposed to this pattern four times a day for 8 consecutive days. The mean latency to enter the goalbox for the four trials that comprised a monotonically decreasing series of pellet amounts (14, 7, 3, 1) was indirectly related to pellet amount. The mean latency on each trial and the degree of change in running speed across trials was found to be directly related to in utero alcohol exposure. Alcohol exposed offspring demonstrated less change in latencies over trials than controls. Also, the mean latency on the last trial for 7 pellets was shorter than that seen on the previous trial (1 pellet) and similar to that seen after the first trial in which 7 pellets were available. This indicated that satiation was not a factor in the increasing latencies. These data indicate a deficit in serial pattern performance as a function of prenatal alcohol exposure similar to what is observed in children with FAS.

Doppler Diastolic Transmitral Flow Patterns in Severe Heart Failure: Response to Controlled Changes in Filling Pressure Using Intravenous Isosorbide Dinitrate

Serial Doppler diastolic transmitral flow patterns were compared with simultaneous hemodynamic measurements in a homogeneous group of patients with severe (New York Heart Association class 4) heart failure who were receiving high dose (508 +/- 271 micrograms/min) intravenous isosorbide dinitrate. The Doppler tracing uniformly showed a severe restrictive pattern, with tall peak early diastolic filling (E) wave (84 +/- 12 cm/s), small late filling (A) wave (28 +/- 8 cm/s) and very high E/A ratio (3.2 +/- 0.8). Isosorbide dinitrate decreased wedge pressure and systemic vascular resistance by a third and increased cardiac index by more than 40%. Transmitral Doppler E/A ratio changed directly in relation to the changes in pulmonary capillary wedge (r = 0.85, p = 0.03) and right atrial pressure (r = 0.84, p = 0.03), indicating preload dependence of transmitral flow velocity, even in severe heart failure.

Clinical profile of biopsy proven idiopathic myocarditis

We studied 20 patients in detail (age: 27 months to 45 years, mean 22 years; 15 males, 5 females) of idiopathic myocarditis histologically confirmed by endomyocardial biopsy. None of these patients had evidence of active or previous rheumatic fever. The commonest mode of presentation was congestive heart failure (16 patients) followed by arrhythmias (seven patients — five of whom had associated congestive heart failure) and chest pain resembling myocardial infarction (two patients). Ten patients had a history of preceding upper respiratory infection. Only one of these patients had a significant rising serum titre for Coxsackie B 3 virus. Throat and rectal swabs for virus culture were negative in all patients. The electrocardiogram was abnormal in all patients, with a prolonged corrected QT-interval being the commonest abnormality (14 patients). Serial electrocardiographic patterns of evolving myocardial infarction occurred in three patients. Echocardiographic left ventricular end diastolic dimension (4.15 ± 1.01 cm/m 2) and end systolic dimension (3.37 ± 1.03 cm/m 2) were increased in 15 of the 18 patients studied. Pericardial involvement occurred in only one patient. Radionuclide ventriculography showed a reduced left ventricular ejection fraction (< 50%) in 17 patients, global hypokinesia in 12 patients and regional wall motion abnormalities in five patients. Left ventricular and right ventricular end diastolic pressures were elevated in 15 and 11 patients, respectively.

Effects of Aging on a Tracking Task of Serial Light Stimulation

The purpose of this study is to examine the serial information processing capacity in children and middle-aged and elderly people by using a tracking task of serial pattern.Subjects tracked two serial patterns twenty times respectively. In experiment I, the task was to switch the key in response to lighting without previous trial. In experiment II, subjects watched the pattern until they felt they had learned it, and then began responding. The stimulus interval (100ms) and the interstimulus interval (500ms) were always constant in experiment I and II. In experiment III, subjects tracked the pattern in 60 trials consisting of 20 trials of three interstimulus intervals (ISI): 500ms, 300ms and 800ms respectively. Samples were 60 right-handed females and males consisting of 10 members of six age groups 8, 10, and 12 years old childern, college students (ages 18-21), the middle (ages 41-43), and the elderly (ages 59-63).College students could approximately execute the switch task in response to lighting in experiment I and II, and 12 years old children could also execute the same task in experiment II. In experiment I the reaction time of 8 and 10 years old children and middle aged and elderly people were longer than that of 12 years old children and college students by 100-400ms. In experiment II, however, the proportion of the anticipatory response of 8 and 10 years old children were more larger than that of other age groups. When the ISI was prolonged from 300ms to 800ms, the proportion of the anticipatory response of children was more noticeable than that of college students.Thus 8 and 10 years old children responded to the learned serial pattern by the anticipatory response. However, performance in the middle and the elderly was slow and stereotyped. Twelve years old children, on the other hand, had the similar response properties as in both 8 and 10 years old ones and college students.

Encoding of a nonmonotonic serial pattern: Role of the dorsal hippocampus and amygdala

The present experiment examined the effects of lesions of the hippocampus, amygdala, or combined hippocampal + amygdala lesions on the acquisition of a presumably difficult serial pattern. Lesioned rats, sham-surgical and nonsurgical control rats were trained in a runway to track one of a four-element series of Noyes food pellets consisting of 14-0-3-7 pellets, respectively. Control rats were capable of tracking the elements of the series. Tracking developed in the amygdala-lesion group by the middle stages of training, but tracking did not develop in the hippocampal-lesion group until the end of training and failed to develop in the hippocampus + amygdala-lesion group. The results are discussed in terms of hippocampus and amygdala involvement in working memory processes. The role of each structure in processing the temporal and affective attributes of the task is considered. Presumably, the hippocampus is necessary for tasks requiring the sequential coding of information. The hippocampus appears to maintain a temporal record of the elements of the series providing the rat with the ability to track which stimulus elements have been presented and which have not. In addition, by processing the effective attributes of the task, the amygdala appears to mediate mnemonic processes.

Temporal and Sequential Structure of Vigilance Behavior of Wild Boars (Sus scrofa)

It has been argued that animals alternating between feeding and vigilance behavior should scan randomly. However, the spectral analysis of individual sequences of scans and interscan intervals obtained from wild boars ( Sus scrofa ) shows the existence of significant periodicities; the scans and interscan intervals oscillate regularly among long and short events. For all the examined series, the serial patterns were similar. However, the temporal patterns vary strongly among individuals and depend upon the number of conspecifics present. These results support the assumption of the existence of general behavioral processes, presumably involving self-sustaining endogenous oscillators.

Serial pattern complexity: irregularity and hierarchy

In perception research, various models have been designed for the encoding of, for example, visual patterns, in order to predict the human interpretation of such patterns. Each of these encoding models provides a few coding rules to obtain codes for a pattern, each code expressing regularity and hierarchy in that pattern. Some of these models employ the minimum principle which states that the human interpretation of a pattern is reflected by the simplest code for that pattern, ie the simplest code according to a given complexity metric. In this paper a new complexity metric is proposed. This metric is based on a formal analysis of the concept of regularity. Some conclusions of this analysis are sketched. The new metric does not depend on artifacts of the coding rules. It accounts for the amounts of irregularity and hierarchy as represented in a code of a pattern, such that these two amounts can be added to determine the complexity of a code. An experiment is discussed that shows that the new metric performs significantly better than the metrics used previously. In particular, the new metric predicts more local pattern organizations than the old metrics. This implies that various local pattern organizations do not falsify the minimum principle anymore.

Serum creatine-kinase-BB concentration in very low birth weight babies with posthemorrhagic ventricular dilatation

The association between measurements of lateral ventricle dilatation determined by serial ultrasound and brain specific creatine-kinase isoenzyme patterns (CK-BB) is studied in 60 very low birth weight preterm neonates of 1,500 g birth weight or 32 weeks gestation or less. The patients were divided into three groups according to cranial ultrasonographic findings: Group A (n = 20) had isolated peri-intraventricular hemorrhage (PIVH); group B (n = 20) had PIVH and dilated ventricles (VM); group C (n = 20) were normal matched preterms and formed the control group. Compared to control babies or those with isolated PIVH, high serum concentrations of CK-BB were observed after birth in babies with persistent dilated ventricles at two weeks postnatal age (p less than 0.01). No difference was found between CK-BB levels of babies with isolated PIVH and control group (p greater than 0.05). We suggest that an elevated CK-BB value is found in babies with persistent ventricular dilatation suggesting severe and diffuse brain damage after post-hemorrhagic ventriculomegaly (VM).

Gender, Class, and Migration in the Dominican Republic: Women's Experiences in a Transnational Community

The experiences of women in one village in the Dominican Republic, Los Pinos, are analyzed as these relate to the dense transnational network of social relations that now link the village to New York City where most Dominican migrants have settled. International migration and gender relations affect 2 groups of Pinera women: 1) those married to US migrants or with migrant offspring in the US and 2) those women who had no household members in the US. As a consequence of the remittances they received, members of the 1st group often constituted the village's transnational middle class; the latter group included some of the poorest members of the community. Subsistence-level remittances also ensured that they were almost totally dependent on husbands to maintain their families. Women in patrilocal, stable marriages with US migrants conformed more readily to prevailing ideals of respectable feminine behavior. Such respectability was also sustained by remittance-subsidized consumption, especially of improved housing and consumer goods. For some of the younger women, however, conforming to these ideals was often an annoying burden. As the locus of many migrants' investments, the village of Los Pinos has experienced a modest growth in the number of full-time jobs paying somewhat above the minimum urban wage and in a variety of petty entrepreneurial activities depending heavily on the patronage of migrant households, themselves heavily subsidized by remittances. Women who followed a serial mating pattern, even some of the poorest, benefited from migration (higher income, consumer goods, visas) through the informal ties they established with migrants and their kin, although all of the desirable new jobs had gone to men. Nevertheless, for both groups of women prevailing gender ideologies impacted the socioeconomic changes stemming from the transnational process to conform to Pinero practice.

Parental care as a constraint on male mating success in fishes: a comparative study of threespine and white sticklebacks

To investigate constraints imposed by male parental behavior on male mating success we compared mate competition in two related 'species' of stickleback, one showing parental care (threespine stickleback, Gasterosteus aculeatus), the other not (white stickleback, Gasterosteus sp.). Three males of each species (tested separately) competed for spawnings with gravid females over a 10-day period. Our findings showed that once a threespine male acquires its first clutch of eggs, the chances of it spawning successively over the next 4 days increase, after which courtship activity declines and parental care of eggs increases. This leads to a serial pattern of spawning amongst the three males in which the second male spawns successively in its nest after the first male has completed its spawnings, followed by the third male, if it spawns at all. However, the third male is more likely to steal fertilizations in the nests of the other two males; stolen fertilizations represented an estimated 29% of the spawning frequency of the third male, compared with 5 and 0% for the second and first males, respectively. The order in which threespine males spawned was correlated with the order in which they initiated nest construction and their ability to defend and maintain a nest site. Immediately after spawning, white stickleback males disperse their eggs among clumps of filamentous algae, where the eggs develop without further parental assistance. In contrast to threespines, white sticklebacks tested under the same competitive conditions showed a random pattern of spawning amongst the three males and stolen fertilizations were not observed. This difference in spawning pattern presumably reflects the time constraint imposed on the sexual phase by the imminent need for parental care once a threespine male obtains eggs. Without the need for parental care of eggs, white males that spawn are not under the same time constraints and therefore each successive spawning is of equal value among competing males, resulting in a random pattern of spawning. In contrast, an asymmetry exists in threespines in which males with freshly spawned eggs in their nest increase their courtship intensity relative to males without eggs, resulting in a serial or ordered pattern of spawning among the males. It is further suggested that stolen fertilizations may be a secondary adaptation to offset any inability to compete effectively for nest sites and females during the initial part of the breeding period.

A review of portable random number generators

Abstract Portable random number generators for personal computers can be evaluated quickly and effectively by plotting their two- and three-dimensional serial patterns. An examination of about 40 published generators yielded only a few that had acceptable serial patterns.

Parallel-processing techniques for automatic test pattern generation

Some of the more widely used serial automatic test pattern generation (ATPG) algorithms and their stability for implementation on a parallel machine are discussed. The basic classes of parallel machines are examined to determine what characteristics they require of an algorithm if they are to implement it efficiently. Several techniques that have been used to parallelize ATPG are presented. They fall into five major categories: fault partitioning, heuristic parallelization, search-space partitioning, functional (algorithmic) partitioning, and topological partitioning. In each category, an overview is given of the technique, its advantages and disadvantages, the type of parallel machine it has been implemented on, and the results.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Transfer of serial stimulus relations by European starlings (Sturnus vulgaris): Loudness.

Four experiments investigated the ability of European starlings (Sturnus vulgaris) to perceive stimulus relations in serial sound patterns. Loudness was the relevant stimulus dimension. In Experiment 1, subjects learned to discriminate between patterns of sine tones that increased and decreased monotonically in loudness. The discrimination tansferred successfully to novel loudness levels outside the baseline training range. Starlings also maintained the discrimination when the loudness intervals between successive pattern elements were doubled in Experiment 2 and when frequency was shifted in Experiment 4

Direct Goal-box Placement Effect on Acquired Performance of Serial Pattern in Rats

Direct Goal-box Placement Effect on Acquired Performance of Serial Pattern in Rats

Effect of interrun interval on serial pattern learning in rats

The effect of interrun interval (IRI) on serial pattern learning was investigated in a runway. One of two serial sequences, a monotonic decreasing sequence (14-7-3-1-0 food pellets) or a nonmonotonic sequence (14-1-3-7-0), was combined factorially with a short (30 s) or a long (30 min) IRI. Following 28 acquisition trials, a short (or long) IRI was transferred to the same sequence with a long (or short) IRI. It was found that anticipation of the O-pellet developed more rapidly in the group receiving a monotonic sequence with a 30 s IRI than that with a 30 min IRI in acquisition phase. The O-pellet was not anticipated by either of the two nonmonotonic groups. Anticipation was eliminated by the increase in IRI, whereas it was developed by the decrease in IRI in the monotonic sequence. These results suggest that time-related factors such as the decay of the memory of numbers of pellets are needed for Capaldi's memory discrimination theory.

Serial pattern learning by event observation.

Serial pattern learning by event observation.

Effects of Interrun interval and Shift of Reward Sequence on Serial Pattern Learning in Rats

In order to examine the effects of interrun intervals (IRI) on serial pattern learning, two groups of nine albino rats each were trained to achieve five consecutive runs in a straight alley and exposed to a series of reward magnitude varying number of 45mg food pellets at each run. In the first stage of the training, the first group (Group S) was presented with 14-7-3-1-0 monotonic series of food pellets with IRI of 15 to 20 sec between runs. The second group (Group L) was also presented with the same series as the first one but with longer IRI of 5 min between runs. Group S and Group L ran equally slow to 0 pellets in the monotonic series. In the second stage of the experiment, both groups received 14-3-7-1-0 nonmonotonic series with the IRI being same as the first stage. The shift of the series differentially affected the anticipation of the 0 pellets between groups. Anticipation of 0 pellet in Group S was more greatly deteriorated than that in Group L. These results support Hulse's dual theoretical approach to serial pattern learning rather than Capaldi's memory-discrimination theory.

Adult age differences in the rate of learning serial patterns: evidence from direct and indirect tests.

Subjects performed a serial reaction time task (adopted from Nissen & Bullemer, 1987) that contained a repeating pattern of spatial locations. In Experiment 1, following 20 repetitions of a 10- or 16-element pattern, reaction time was equally disrupted for both younger and older people when the sequence became random. In Experiment 2, the response times for subjects encountering the 10-element pattern were compared with those of subjects encountering a random sequence. These response time functions diverged at the same point in training for the 2 age groups. Thus, on this indirect measure of response time facilitation, both experiments revealed age similarity in the rate of pattern learning. In contrast, on a subsequent direct test of pattern learning that required prediction, the younger people earned a higher percentage correct score than the older in both experiments. Age-related dissociations between direct and indirect measures of learning and comparisons with memory-impaired populations are discussed.

Adult age differences in the rate of learning serial patterns: Evidence from direct and indirect tests.

Adult age differences in the rate of learning serial patterns: Evidence from direct and indirect tests.