Continuous, quantized and modal variation

1960 ◽  
Vol 152 (948) ◽  
pp. 397-409 ◽  
Keyword(s):  
Developmental Process ◽  
Field Size ◽  
Counting Processes ◽  
Continuous Variables ◽  
Modal Number ◽  
Integral Number ◽  
Modal Variation ◽  
Animal Populations ◽  
Almost All ◽  
Multiplicative Processes

Intraspecific variation may be continuous, or it may be quantized, if the number of structures present is always an integer. If there is some modal number of structures present in almost all individuals, variation is said to be modal. A developmental process is defined as one of ‘simple quantization’ if, first, it gives rise to an integral number of structures, and secondly, if the number of structures formed depends on the ratio between two continuous variables, for example the field size and the chemical wavelength in the model suggested by Turing (1952). Whether variation is quantized or modal will then depend on the accuracy with which these continuous variables are regulated. The larger the modal number, the more accurate must this regulation be. Data on the range of continuous variation within animal populations sug­gest that simple quantization cannot give rise to modal numbers greater than about 5 to 7. Yet modal numbers of 30 or more occur. Three processes which might account for this dis­crepancy are suggested, and evidence is presented to show that two of them occur. These are ‘multiplicative’ processes, involving successive processes of simple quantization, and ‘chemical counting’ processes, depending on qualitative differences between successively formed structures. The relevance of processes of quantization to the genesis of two-dimensional patterns is discussed.

Changes in the response properties of neurons in the ventroposterior lateral thalamic nucleus of the raccoon after peripheral deafferentation

1996 ◽  
Vol 75 (6) ◽  
pp. 2441-2450 ◽  
Author(s):  
D. D. Rasmusson
Keyword(s):  
Receptive Field ◽  
Thalamic Nucleus ◽  
Receptive Fields ◽  
Field Size ◽  
Mechanical Stimuli ◽  
Sensory Pathways ◽  
Average Latency ◽  
Somatotopic Map ◽  
Almost All ◽  
Stimulation Of

1. Single neurons in the ventroposterior lateral thalamic nucleus were studied in 10 anesthetized raccoons, 4 of which had undergone amputation of the fourth digit 4-5 mo before recording. Neurons with receptive fields on the glabrous skin of a forepaw digit were examined in response to electrical stimulation of the “on-focus” digit that contained the neuron's receptive field and stimulation of an adjacent, “off-focus” digit. 2. In normal raccoons all neurons responded to on-focus stimulation with an excitation at a short latency (mean 13 ms), whereas only 63% of the neurons responded to off-focus digit stimulation. The off-focus responses had a longer latency (mean 27.2 ms) and a higher threshold than the on-focus responses (800 and 452 microA, respectively). Only 3 of 32 neurons tested with off-focus stimulation had both a latency and a threshold within the range of on-focus values. Inhibition following the excitation was seen in the majority of neurons with both types of stimulation. 3. In the raccoons with digit removal, the region of the thalamus that had lost its major peripheral input (the “deafferented” region) was distinguished from the normal third and fifth digit regions on the basis of the sequence of neuronal receptive fields within a penetration and receptive field size as described previously. 4. Almost all of the neurons in the deafferented region (91%) were excited by stimulation of one or both adjacent digits. The average latency for these responses was shorter (15.3 ms) and the threshold was lower than was the case with off-focus stimulation in control animals. These values were not significantly different from the responses to on-focus stimulation in the animals with digit amputation. 5. These results confirm that reorganization of sensory pathways can be observed at the thalamic level. In addition to the changes in the somatotopic map that have been shown previously with the use of mechanical stimuli, the present paper demonstrates an improvement in several quantitative measures of single-unit responses. Many of these changes suggest that this reorganization could be explained by an increased effectiveness of preexisting, weak connections from the off-focus digits; however, the increase in the proportion of neurons responding to stimulation of adjacent digits may indicate that sprouting of new connections also occurs.

scholarly journals Estimation of Out-of-Field Dose Variation using Markus Ionization Chamber Detector

2020 ◽  
Vol 2 (1) ◽  
pp. 8-15
Author(s):  
Ahmed M. Abdelaal ◽  
Ehab M. Attalla ◽  
Wael M. Elshemey
Keyword(s):  
Ionization Chamber ◽  
Field Size ◽  
The Poor ◽  
Collimator Angle ◽  
Different Depths ◽  
Almost All ◽  
Dose Variation

Objective: The aim of This work to provide evaluation  for the out-of-field dose with different plan parameters as field size and depth using Markus ionization chamber detector in the measurement that are frequently used in electron and superficial dosimetery, in radiotherapy. Methods: This is carried out through the application of these detector in estimation of the out-of-field dose with important dosimetric parameters such as field size (from 5×5 to 30×30 cm2) and depth (from 1.5 to 30 cm) at energy 6 MV and collimator angle 0° at SSD 100 cm. Results: Results show that, the Markus detector reported an increase in out-of-field dose with field size, depth in almost all measurements. For 6 MV and 0° collimator  angle, the out-of-field dose at field size of 5×5 cm2 (depth of 1.5 cm) is 1.1%  and at field size of  30×30 cm2 (depth of 1.5 cm) is 4.4% . The out-of-field dose for a depth of 1.5 cm (field size of 10×10 cm2) is 2.3% and for a depth of 30 cm (field size of 10×10 cm) is 5.5%. the measured out-of-field dose by Markus detector overestimated in the calculated at different field sizes (2.7% instead of 2.3% at field size of 10×10 cm2 and 5.2% instead of 4.4% at field size of 30×30 cm2) and different depths (2.7% instead of 1.1% at depth of 1.5 cm and 4.1% instead of 3.4% at depth of 30 cm). Analysis: The result reported an increase in mean out-of-field dose with field size, depth, energy and SSD. Markus ionization chamber detector show overestimation of the measured out-of-field dose in the calculated values at all field sizes and depths, this may be attributed to the poor detection of out-of-field dose by TPS.

Nursing homes’ preparedness plans and capabilities

2012 ◽  
Vol 7 (2) ◽  
pp. 127-135 ◽  
Author(s):  
Hilary Eiring, MPH ◽  
Sarah C. Blake, MA, PhD Candidate ◽  
David H. Howard, PhD
Keyword(s):  
Nursing Home ◽  
Nursing Homes ◽  
Disaster Preparedness ◽  
Categorical Variables ◽  
Continuous Variables ◽  
Probit Regression ◽  
Nursing Home Administrators ◽  
Local Officials ◽  
Almost All ◽  
Question Survey

Objectives: To assess nursing homes’ capabilities to evacuate or shelter-in-place during a disaster and to determine their actual preparedness-related capacity.Design: A 27-question survey assessing disaster preparedness plans and capabilities in nursing homes. Respondents and nonresponders were compared based on characteristics from the Nursing Home Compare Web site using t tests for continuous variables and χ2 test for categorical variables. Probit regression was used to estimate the relationships between nursing home characteristics and dichotomous measures of preparedness.Setting: Web and paper surveys of nursing home administrators.Participants: Nursing home administrators in California, Florida, and Georgia.Main outcome measures: Number of disaster drills, days supply of emergency food and water, evacuation transportation and destination.Results: All facilities reported conducting at least one disaster drill per year. Only 55 percent of facilities used a template to develop their disaster plans and 74 percent of facilities reported that they discuss their disaster plans with local or state emergency management officials. Most facilities (81 percent) have generators. All but 19 (7 percent) of nursing homes are able to shelterin- place for 2 days or longer. Ambulance services are the most common form of transportation (76 percent). Most facilities (73 percent) plan to evacuate residents to nursing homes affiliated with their corporate group.Discussion: Almost all respondents conducted disaster drills, discussed preparedness with local officials, and were able to shelter-in-place for at least 2 days. However, many facilities rely on resources that may not be available during a large disaster.

scholarly journals Comparison of Selected Multiple Imputation Methods for Continuous Variables – Preliminary Simulation Study Results

2019 ◽  
Vol 6 (339) ◽  
pp. 73-98
Author(s):  
Małgorzata Aleksandra Misztal
Keyword(s):  
Missing Data ◽  
Multiple Imputation ◽  
Missing Values ◽  
Imputation Accuracy ◽  
Imputation Method ◽  
Data Sets ◽  
Continuous Variables ◽  
Imputation Methods ◽  
Study Results ◽  
Almost All

The problem of incomplete data and its implications for drawing valid conclusions from statistical analyses is not related to any particular scientific domain, it arises in economics, sociology, education, behavioural sciences or medicine. Almost all standard statistical methods presume that every object has information on every variable to be included in the analysis and the typical approach to missing data is simply to delete them. However, this leads to ineffective and biased analysis results and is not recommended in the literature. The state of the art technique for handling missing data is multiple imputation. In the paper, some selected multiple imputation methods were taken into account. Special attention was paid to using principal components analysis (PCA) as an imputation method. The goal of the study was to assess the quality of PCA‑based imputations as compared to two other multiple imputation techniques: multivariate imputation by chained equations (MICE) and missForest. The comparison was made by artificially simulating different proportions (10–50%) and mechanisms of missing data using 10 complete data sets from the UCI repository of machine learning databases. Then, missing values were imputed with the use of MICE, missForest and the PCA‑based method (MIPCA). The normalised root mean square error (NRMSE) was calculated as a measure of imputation accuracy. On the basis of the conducted analyses, missForest can be recommended as a multiple imputation method providing the lowest rates of imputation errors for all types of missingness. PCA‑based imputation does not perform well in terms of accuracy.

scholarly journals Large genotype–phenotype study in carriers of D4Z4 borderline alleles provides guidance for facioscapulohumeral muscular dystrophy diagnosis

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Giulia Ricci ◽  
Fabiano Mele ◽  
Monica Govi ◽  
Lucia Ruggiero ◽  
Francesco Sera ◽  
...  
Keyword(s):  
Genetic Counseling ◽  
Muscular Dystrophy ◽  
Family Studies ◽  
Motor Impairment ◽  
Facioscapulohumeral Muscular Dystrophy ◽  
Molecular Testing ◽  
Integral Number ◽  
Almost All ◽  
Conclusive Diagnosis ◽  
Index Cases

AbstractFacioscapulohumeral muscular dystrophy (FSHD) is a myopathy with prevalence of 1 in 20,000. Almost all patients affected by FSHD carry deletions of an integral number of tandem 3.3 kilobase repeats, termed D4Z4, located on chromosome 4q35. Assessment of size of D4Z4 alleles is commonly used for FSHD diagnosis. However, the extended molecular testing has expanded the spectrum of clinical phenotypes. In particular, D4Z4 alleles with 9–10 repeat have been found in healthy individuals, in subjects with FSHD or affected by other myopathies. These findings weakened the strict relationship between observed phenotypes and their underlying genotypes, complicating the interpretation of molecular findings for diagnosis and genetic counseling. In light of the wide clinical variability detected in carriers of D4Z4 alleles with 9–10 repeats, we applied a standardized methodology, the Comprehensive Clinical Evaluation Form (CCEF), to describe and characterize the phenotype of 244 individuals carrying D4Z4 alleles with 9–10 repeats (134 index cases and 110 relatives). The study shows that 54.5% of index cases display a classical FSHD phenotype with typical facial and scapular muscle weakness, whereas 20.1% present incomplete phenotype with facial weakness or scapular girdle weakness, 6.7% display minor signs such as winged scapula or hyperCKemia, without functional motor impairment, and 18.7% of index cases show more complex phenotypes with atypical clinical features. Family studies revealed that 70.9% of relatives carrying 9–10 D4Z4 reduced alleles has no motor impairment, whereas a few relatives (10.0%) display a classical FSHD phenotype. Importantly all relatives of index cases with no FSHD phenotype were healthy carriers. These data establish the low penetrance of D4Z4 alleles with 9–10 repeats. We recommend the use of CCEF for the standardized clinical assessment integrated by family studies and further molecular investigation for appropriate diagnosis and genetic counseling. Especially in presence of atypical phenotypes and/or sporadic cases with all healthy relatives is not possible to perform conclusive diagnosis of FSHD, but all these cases need further studies for a proper diagnosis, to search novel causative genetic defects or investigate environmental factors or co-morbidities that may trigger the pathogenic process. These evidences are also fundamental for the stratification of patients eligible for clinical trials. Our work reinforces the value of large genotype–phenotype studies to define criteria for clinical practice and genetic counseling in rare diseases.

92 Is Virtual Burn Camp as Effective as In-Person Burn Camp?

2021 ◽  
Vol 42 (Supplement_1) ◽  
pp. S63-S64
Author(s):  
Jennifer B Radics-Johnson ◽  
Li Zhang ◽  
Anwen Huang ◽  
Daniel W Chacon
Keyword(s):  
Response Rate ◽  
Statistical Significance ◽  
The Other ◽  
Categorical Variables ◽  
P Value ◽  
Continuous Variables ◽  
The Public ◽  
Self Evaluation ◽  
Burn Survivors ◽  
Almost All

Abstract Introduction Burn camps provide a safe haven for child burn survivors to socialize and participate in recreational activities away from the unwanted stares from the public. But when a worldwide pandemic forced one of the world’s largest burn camps to forgo an in-person camp and pivot to a virtual camp, would the virtual burn camp prove as effective as an in-person burn camp? Methods In a 4-year retrospective review of camper evaluations within 2017–2020, we aimed to assess if the campers’ evaluation responses of virtual camp were consistent with their responses from past in-person camp evaluations. Camper self-evaluation forms were reviewed to record camper responses to questions regarding their opinions on camp. Camp rosters were reviewed to determine which campers attended virtual Burn Camp in 2020 as well as in-person Burn Camp among the years 2017–2019, and matched sample comparisons were reviewed (2020 vs. 2017; 2020 vs. 2018 and 2020 vs. 2019). Categorical variables were summarized as frequency and percentage, and continuous variables were described as median and range. To assess if the responses to each question were consistent between 2020 vs. 2017, 2018 and 2019, McNemar’s test was used. Statistical significance was declared based on a p value< 0.05. Results Within 2017–2020, there were 444 camper evaluations submitted. In 2020, there were 137 registered campers. Sample size of this study was small due to a low response rate to evaluation form requests from virtual Burn Camp participants. There were 31 individual completed evaluations forms (23% response rate). Among 31 campers, 20, 22 and 20 campers attended 2017, 2018, and 2019 in-person Burn Camp, respectively. Participants’ demographic characteristics are summarized in Table 1. Comparisons between 2020 vs. 2017, 2018 and 2019, in general, the campers’ responses were consistent. However, for Question #8 (Did you learn anything new from the other burn survivors at this event?) in 2020, more people (n=8) answered Not/A little while they answered Yes/Mostly in 2019 (p=0.046). Participants’ responses to Question#8 are summarized in Tables 2 and 3. Conclusions Virtual Burn Camp was generally as effective as in-person Burn Camp in almost all areas of assessment, except for the ability for burn-injured children to learn from other burn-injured children. The virtual Burn Camp model provided some interaction between counselors and campers, but did not allow for much interaction between campers, resulting in a greater response of “A Little” or “Not at All” to the question “Did you learn anything new from the other burn survivors at this event?”

scholarly journals Monitoring the Natural Focal Indicators of a Parasitic System in the Rural and Urban Territories

2019 ◽  
Vol 8 (4) ◽  
pp. 9013-9022
Keyword(s):  
Expert Assessment ◽  
Ecological Niches ◽  
Rural And Urban ◽  
Animal Populations ◽  
Urban Territories ◽  
In The Wild ◽  
Epizootic Process ◽  
Parasitic System ◽  
Almost All ◽  
Nizhny Novgorod Region

Currently, leptospirosis is identified in many countries, on almost all continents of the globe with various frequencies of occurrence and severity. This is one of the most widespread natural focal infections in Russia. Active circulation of the pathogen in the wild creates a constant threat of the disease occurrence, both among animals and humans. This article presents the results of expert assessment of the functioning of a leptospirosis parasitic system on the territory of the Nizhny Novgorod region based on the materials of the Regional Veterinary Laboratory for the years 2014 through 2018. During the work, the etiological structure of leptospirosis, the host composition of its pathogen, and the dynamics of the epizootic process were determined in the populations of cattle, horses, pigs, and other animal species. Based on the obtained information, a conclusion was made about the trends of developing an infectious parasitic system in animal populations of various species within their ecological niches. The results of the studies obtained by the team of authors form the scientific and information base — the basis for optimizing and implementing a system of anti-epidemic safety in the Nizhny Novgorod region.

Family Studies and Changing Concepts of Personality Development

1979 ◽  
Vol 24 (7) ◽  
pp. 621-632 ◽  
Author(s):  
Theodore Lidz
Keyword(s):  
Developmental Process ◽  
Personality Development ◽  
Developmental Theory ◽  
The Unconscious ◽  
Psychiatric Syndrome ◽  
Individuation Process ◽  
The Family ◽  
Genital Development ◽  
Almost All ◽  
Positive Input

Summary Many of the most significant changes in concepts of personality development and maldevelopment derive simply from belated appreciation that the child grows up in a family; and that the child requires considerable positive input from those who raise him to grow into a reasonably integrated person. Only recently have psychiatrists and psychoanalysts begun to focus on the influence of the family transactions throughout the formative years. The paper briefly presents the requisites a family must provide to assure the integrated development of its offspring and groups them under four headings: the parental nurturant functions that change with each phase of the offspring's development; the influence of the dynamic organization of the family on the offspring's intrapsychic structure, affecting self-boundaries, gender identity, superego directives, and so forth; conveying through family transactions the basic social roles and societal institutions to the child; transmitting the instrumental techniques of the culture, and particularly its language with its system of meanings and logic upon which virtually all ego functioning depends. The paper considers the evidence that the “choice of the neurosis” — or more correctly, the choice of the psychiatric syndrome — does not depend only upon fixation at various phases of pre-genital development, but also, and perhaps primarily, upon the panphasic influence of the intrafamilial environment. It is of particular importance to recognize that there is a very direct relationship between the family transactions, the separation-individuation process, boundary formation, the attainment of various degrees of object constancy, problems of splitting, superego directives, and what can be conscious and what need be repressed into the unconscious. The failure to recognize the import of the family has interfered with the formation of an integrated developmental theory that can unite various aspects of the developmental process that have remained more or less isolated from one another — drive theory, object relations, ego psychology, separation-individuation, and cognitive development. Finally the question is raised if in providing guidance to parents we have been amiss in not focusing on such matters as who the parents are, how they relate to one another as well as to the child, the values they communicate by their behaviour — matters that are fundamental and to which almost all else is secondary, but about which relatively little has been said or taught.

scholarly journals Evaluation of Knowledge, Attitude, Practice and Hospital Experience Regarding COVID-19 among Post-partum Mothers at a Tertiary Care Center: A Cross-sectional Study

2020 ◽  
Vol 18 (2) ◽  
pp. 10-14
Author(s):  
S.P. Adhikari ◽  
J. Pariyar ◽  
K. Sapkota ◽  
T.K. Gurung ◽  
S.R. Adhikari
Keyword(s):  
Post Partum ◽  
Care Center ◽  
Tertiary Care ◽  
Categorical Variables ◽  
Tertiary Care Center ◽  
Continuous Variables ◽  
Cross Sectional ◽  
Hospital Experience ◽  
Pregnancy And Postpartum ◽  
Almost All

Background: Pregnant and breastfeeding women are more susceptible to viral infection and in the year 2020 they have to face the COVID-19 pandemic. Since, no successful treatment and vaccine has been developed so far, efforts to enhance the knowledge, attitudes, and practice of the public, especially the high-risk groups like pregnancy and postpartum period are crucial to manage COVID-19 pandemic. Objective To analyze the knowledge, attitude, practice and hospital experience regarding COVID-19 among post-partum mothers at a tertiary care center of Nepal Method The data collection was based on direct interview after receiving written consent from the research participants, using a semi-structured questionnaire. The questionnaire consisted of 4 major domains- knowledge (8 questions), attitude (6 questions), practice (5 questions) and experience (5 questions). Standard descriptive statistics were used for the data, mean and standard deviation for continuous variables whereas frequencies and percentages for categorical variables. Result A total of 203 post-partum women participated in the study. Almost all the participants had heard about COVID-19 (96.6%). A majority of them were aware about how COVID-19 gets transmitted and its preventive measures. Most of the participants (88.2%) knew that COVID-19 has effects on pregnancy. Almost all of participants (97%) wore mask during hospital stay. All of the women washed their hands with soap water or alcohol based sanitizer. A majority of the mothers (79.3%) wore mask while breastfeeding their baby. Conclusion The post-partum mothers have good knowledge, attitude, practice and experiences regarding the COVID-19 pandemic.

Integrating perspectives: How the development of second-personal competence lays the foundation for a second-personal morality

2020 ◽  
Vol 43 ◽  
Author(s):  
John Corbit ◽  
Chris Moore
Keyword(s):  
Empirical Evidence ◽  
Developmental Process ◽  
Focal Point ◽  
Personal Information ◽  
Personal Competence ◽  
Triadic Interactions ◽  
Personal Morality ◽  
Integrative Process

Abstract The integration of first-, second-, and third-personal information within joint intentional collaboration provides the foundation for broad-based second-personal morality. We offer two additions to this framework: a description of the developmental process through which second-personal competence emerges from early triadic interactions, and empirical evidence that collaboration with a concrete goal may provide an essential focal point for this integrative process.

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