A nucleation–growth process on the integers

1987 ◽  
Vol 19 (01) ◽  
pp. 26-43
Author(s):  
Bernhard Mellein
Keyword(s):  
Spatial Distribution ◽  
Markov Process ◽  
Size Distribution ◽  
Growth Process ◽  
Competitive Growth ◽  
Final State ◽  
Left Hand ◽  
Right Hand ◽  
Maximal Sequence ◽  
Nearest Neighbours

We consider a Markov process with state space {0, 1} Z where Os become 1s irreversibly at rates which depend on whether none of a 0&s nearest neighbours (nucleation), its left-hand neighbour (right-hand growth), or its right-hand neighbour (left-hand growth) is in the 1-state. Furthermore, we assume that Os with both nearest neighbours in the 1-state remain in the 0-state forever and that at time 0 only the origin is in the 1-state. We determine the size distribution of the cluster (maximal sequence of 1s uninterrupted by Os) at the origin and the distribution of the time when its growth is stopped (by birth (nucleation) or competitive growth of neighbouring clusters). In the final state of the process, the spatial distribution of the (trapped) sites in the 0-state is considered. Some information on the size distribution of clusters well away from the cluster at the origin is obtained.

A nucleation–growth process on the integers

1987 ◽  
Vol 19 (1) ◽  
pp. 26-43
Author(s):  
Bernhard Mellein
Keyword(s):  
Spatial Distribution ◽  
Markov Process ◽  
Size Distribution ◽  
Growth Process ◽  
Competitive Growth ◽  
Final State ◽  
Left Hand ◽  
Right Hand ◽  
Maximal Sequence ◽  
Nearest Neighbours

We consider a Markov process with state space {0, 1}Z where Os become 1s irreversibly at rates which depend on whether none of a 0&s nearest neighbours (nucleation), its left-hand neighbour (right-hand growth), or its right-hand neighbour (left-hand growth) is in the 1-state. Furthermore, we assume that Os with both nearest neighbours in the 1-state remain in the 0-state forever and that at time 0 only the origin is in the 1-state. We determine the size distribution of the cluster (maximal sequence of 1s uninterrupted by Os) at the origin and the distribution of the time when its growth is stopped (by birth (nucleation) or competitive growth of neighbouring clusters). In the final state of the process, the spatial distribution of the (trapped) sites in the 0-state is considered. Some information on the size distribution of clusters well away from the cluster at the origin is obtained.

scholarly journals Size Distribution of States, Counties, and Cities in the USA: New Inequality Form Information

2020 ◽  
Author(s):  
Gennady Grachev
Keyword(s):  
Power Series ◽  
Size Distribution ◽  
Lognormal Distribution ◽  
Power Series Distribution ◽  
Left Hand ◽  
Settlement Systems ◽  
Pareto Curve ◽  
Right Hand ◽  
Wide Range ◽  
The Usa

In this article, we propose a new approach for studying the patterns of size distribution in settlement systems, based on the analysis of the shape of the Pareto curve (PC). To study the shape of the PC, we used the Gini coefficient, the asymmetry coefficient, and, by analogy with the physics of phase transitions, critical exponent — the index of the PC degree in the neighborhood of zero. An empirical analysis of the PC of various levels of aggregation in the US settlement system has been performed. The form of size distribution of states was studied by decades from 1790 to 2010. The spatial analysis of the PC shape for counties and cities was performed for 2010. The results of an empirical study showed that the PC of the states had left-hand asymmetry over 220 years. The PC of districts and cities had both right-hand and left-hand asymmetries. The obtained results explain in which cases the Pareto distribution having a PC with right-hand asymmetry, and the lognormal distribution with a symmetric PC may not correspond objectively to real settlement systems. As an alternative to power-series distribution and lognormal distribution, we considered an analytically simple two-parameter model with a wide range of PC asymmetry that combines the properties of power-series distribution and lognormal distribution. Verification of the model showed that it adequately described the size of settlements in homogeneous settlement systems.

Editorial Note

1946 ◽  
Vol 11 (1) ◽  
pp. 2-2
Keyword(s):  
Editorial Note ◽  
Speech Sounds ◽  
Left Hand ◽  
Hand Column ◽  
Right Hand ◽  
Infant Speech ◽  
The Right

In the article “Infant Speech Sounds and Intelligence” by Orvis C. Irwin and Han Piao Chen, in the December 1945 issue of the Journal, the paragraph which begins at the bottom of the left hand column on page 295 should have been placed immediately below the first paragraph at the top of the right hand column on page 296. To the authors we express our sincere apologies.

Alive Still

2019 ◽  
Author(s):  
Cathy Curtis
Keyword(s):  
New York ◽  
Modern Art ◽  
Severe Form ◽  
The Other ◽  
Left Hand ◽  
Right Hand ◽  
The 1950S ◽  
Village Voice

In 1942, at age twenty, after a vision-impaired and rebellious childhood in Richmond, Virginia, Nell Blaine decamped for New York. Operations had corrected her eyesight, and she was newly aware of modern art, so different from the literal style of her youthful drawings. In Manhattan, she met rising young artists and poets. Her life was hectic, with raucous parties in her loft, lovers of both sexes, and freelance design jobs, including a stint at the Village Voice. Initially drawn to the rigorous formalism of Piet Mondrian, she received critical praise for her jazzy abstractions. During the 1950s, she began to paint interiors and landscapes. By 1959, when the Whitney Museum purchased one of her paintings, her career was firmly established. That year, she contracted a severe form of polio on a trip to Greece; suddenly, she was a paraplegic. Undaunted, she taught herself to paint in oil with her left hand, reserving her right hand for watercolors. In her postpolio work, she achieved a freer style, expressive of the joy she found in flowers and landscapes. Living half the year in Gloucester, Massachusetts, and the other half in New York, she took special delight in painting the views from her windows and from her country garden. Critics found her new style irresistible, and she had a loyal circle of collectors; still, she struggled to earn enough money to pay the aides who made her life possible. At her side for her final twenty-nine years was her lover, painter Carolyn Harris.

scholarly journals Digit Variability in Carotenoid Scores Obtained with the Veggie Meter: A Pilot Study (P02-001-19)

2019 ◽  
Vol 3 (Supplement_1) ◽  
Author(s):  
Velarie Ansu ◽  
Stephanie Dickinson ◽  
Alyce Fly
Keyword(s):  
Indiana University ◽  
Left Hand ◽  
Funding Sources ◽  
Right Hand ◽  
Period Data ◽  
The Mean ◽  
The Right ◽  
Post Hoc ◽  
Main Effects ◽  
Mean Square Errors

Abstract Objectives To determine which digit and hand have the highest and lowest skin carotenoid scores, to compare inter-and-intra-hand variability of digits, and to determine if results are consistent with another subject. Methods Two subjects’ first(F1), second(F2), third(F3) and fifth(F5) digits on both hands were measured for skin carotenoids with a Veggie Meter, for 3 times on each of 18 days over a 37-day period. Data were subjected to ANOVA in a factorial treatment design to determine main effects for hand (2 levels), digits (4), and days (18) along with interactions. Differences between digits were determined by Tukey's post hoc test. Results There were significant hand x digit, hand x day, digit x day, and hand x digit x day interactions and significant simple main effects for hand, digit, and day (all P < 0.001). Mean square errors were 143.67 and 195.62 for subject A and B, respectively, which were smaller than mean squares for all main effects and interactions. The mean scores ± SD for F1, F2, F3, and F5 digits for the right vs left hands for subject A were F1:357.13 ± 45.97 vs 363.74 ± 46.94, F2:403.17 ± 44.77 vs. 353.20 ± 44.13, F3:406.76 ± 43.10 vs. 357.11 ± 45.13, and F5:374.95 ± 53.00 vs. 377.90 ± 47.38. For subject B, the mean scores ± SD for digits for the right vs left hands were F1:294.72 ± 61.63 vs 280.71 ± 52.48, F2:285.85 ± 66.92 vs 252.67 ± 67.56, F3:268.56 ± 57.03 vs 283.22 ± 45.87, and F5:288.18 ± 34.46 vs 307.54 ± 40.04. The digits on the right hand of both subjects had higher carotenoid scores than those on the left hands, even though subjects had different dominant hands. Subject A had higher skin carotenoid scores on the F3 and F2 digits for the right hand and F5 on the left hand. Subject B had higher skin carotenoid scores on F5 (right) and F1 (left) digits. Conclusions The variability due to hand, digit, and day were all greater than that of the 3 replicates within the digit-day for both volunteers. This indicates that data were not completely random across the readings when remeasuring the same finger. Different fingers displayed higher carotenoid scores for each volunteer. There is a need to conduct a larger study with more subjects and a range of skin tones to determine whether the reliability of measurements among digits of both hands is similar across the population. Funding Sources Indiana University.

Upper Extremity Motor Fatigability as an Early Indicator in Pediatric Onset Multiple Sclerosis

2021 ◽  
pp. 088307382199988
Author(s):  
Giuseppina Pilloni ◽  
Martin Malik ◽  
Raghav Malik ◽  
Lauren Krupp ◽  
Leigh Charvet
Keyword(s):  
Multiple Sclerosis ◽  
Grip Strength ◽  
Upper Extremity ◽  
Static Fatigue ◽  
Healthy Controls ◽  
Fatigue Index ◽  
Left Hand ◽  
Right Hand ◽  
Computer Based ◽  
Pediatric Onset

Aim: To adopt a computer-based protocol to assess grip fatigability in patients with pediatric-onset multiple sclerosis to provide detection of subtle motor involvement identifying those patients most at risk for future decline. Method: Pediatric-onset multiple sclerosis patients were recruited during routine outpatient visits to complete a grip assessment and compared to a group of healthy age- and sex-matched controls. All participants completed a computer-based measurement of standard maximal grip strength and repetitive and sustained grip performance measured by dynamic and static fatigue indices. Results: A total of 38 patients with pediatric-onset multiple sclerosis and 24 healthy controls completed the grip protocol (right-hand dominant). There were no significant group differences in maximal grip strength bilaterally (right: 21.8 vs 19.9 kg, P = .25; left: 20.4 vs 18.7 kg, P = .33), although males with pediatric-onset multiple sclerosis were significantly less strong than healthy controls (right: 26.53 vs 21.23 kg, P = .009; left; 25.13 vs 19.63 kg, P = .003). Both dynamic and static fatigue indices were significantly higher bilaterally in pediatric-onset multiple sclerosis compared with healthy control participants (left-hand dynamic fatigue index: 18.6% vs 26.7%, P = .003; right-hand static fatigue index: 28.3% vs 41.3%, P < .001; left-hand static fatigue index: 31.9% vs 42.6%, P < .001). Conclusion: Brief repeatable grip assessment including measures of dynamic and sustained static output can be a sensitive indicator of upper extremity motor involvement in pediatric-onset multiple sclerosis, potentially identifying those in need of intervention to prevent future disability.

scholarly journals Examination and Comparison of Theta Band Connectivity in Left- and Right-Hand Dominant Individuals throughout a Motor Skill Acquisition

Symmetry ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 728
Author(s):  
Jessica McDonnell ◽  
Nicholas P Murray ◽  
Sungwoo Ahn ◽  
Stefan Clemens ◽  
Erik Everhart ◽  
...  
Keyword(s):  
Skill Acquisition ◽  
Information Integration ◽  
Visual Information ◽  
Parietal Lobe ◽  
The United States ◽  
Alternative Methods ◽  
Population Difference ◽  
Left Hand ◽  
Right Hand ◽  
Neurological Differences

The majority of the population identifies as right-hand dominant, with a minority 10.6% identifying as left-hand dominant. Social factors may partially skew the distribution, but it remains that left-hand dominant individuals make up approximately 40 million people in the United States alone and yet, remain underrepresented in the motor control literature. Recent research has revealed behavioral and neurological differences between populations, therein overturning assumptions of a simple hemispheric flip in motor-related activations. The present work showed differentially adaptable motor programs between populations and found fundamental differences in methods of skill acquisition highlighting underlying neural strategies unique to each population. Difference maps and descriptive metrics of coherent activation patterns showed differences in how theta oscillations were utilized. The right-hand group relied on occipital parietal lobe connectivity for visual information integration necessary to inform the motor task, while the left-hand group relied on a more frontal lobe localized cognitive based approach. The findings provide insight into potential alternative methods of information integration and emphasize the importance for inclusion of the left-hand dominant population in the growing conceptualization of the brain promoting the generation of a more complete, stable, and accurate understanding of our complex biology.

The State Policy towards the Homeless in Moldova between the ‘Left Hand’ and the ‘Right Hand’. The Case of Chișinău Shelter

Südosteuropa ◽  
2019 ◽  
Vol 67 (2) ◽  
pp. 175-195
Author(s):  
Petru Negură
Keyword(s):  
Homeless People ◽  
Severe Disabilities ◽  
The State ◽  
Small Scale ◽  
Left Hand ◽  
Right Hand ◽  
Binary Approach ◽  
The One ◽  
The Right ◽  
Depth Interviews

Abstract The Centre for the Homeless in Chișinău embodies on a small scale the recent evolution of state policies towards the homeless in Moldova (a post-Soviet state). This institution applies the binary approach of the state, namely the ‘left hand’ and the ‘right hand’, towards marginalised people. On the one hand, the institution provides accommodation, food, and primary social, legal assistance and medical care. On the other hand, the Shelter personnel impose a series of disciplinary constraints over the users. The Shelter also operates a differentiation of the users according to two categories: the ‘recoverable’ and those deemed ‘irrecoverable’ (persons with severe disabilities, people with addictions). The personnel representing the ‘left hand’ (or ‘soft-line’) regularly negotiate with the employees representing the ‘right hand’ (‘hard-line’) of the institution to promote a milder and a more humanistic approach towards the users. This article relies on multi-method research including descriptive statistical analysis with biographical records of 810 subjects, a thematic analysis of in-depth interviews with homeless people (N = 65), people at risk of homelessness (N = 5), professionals (N = 20) and one ethnography of the Shelter.

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