scholarly journals Structural and Function Correlation of Cone Packing Utilizing Adaptive Optics and Microperimetry

2015 ◽  
Vol 2015 ◽  
pp. 1-4 ◽  
Author(s):  
Dabir Supriya ◽  
Mangalesh Shwetha ◽  
Kumar Kiran Anupama ◽  
Kurian Kummelil Mathew ◽  
Tos T. J. M. Berendschot ◽  
...  
Keyword(s):  
Adaptive Optics ◽  
Packing Density ◽  
Statistical Significance ◽  
Retinal Sensitivity ◽  
Cone Mosaic ◽  
Functional Aspects ◽  
Function Correlation ◽  
Correlation Tests ◽  
And Function ◽  
Age Range

Aim. To assess the functional aspects of cone mosaic and correlate cone packing with retinal sensitivity utilizing microperimetry in emmetropes at different eccentricities.Methods. Twenty-four healthy volunteers underwent microperimetry (MAIA Centervue, Italy) and assessment of photoreceptors using adaptive optics retinal camera, rtx1 (Imagine Eyes, Orsay, France), at 2 and 3 degrees from the foveal centre in 4 quadrants: superior, inferior, temporal, and nasal. Data was analyzed using SPSS version 17 (IBM). Spearman’s correlation tests were used to establish correlation between mean cone packing density and retinal sensitivity at different quadrants.Results. Thirteen females and 11 males (age range 20–40 years) were included. The cone density was found to be significantly different among all quadrants (temporal = 25786.68/mm2 ± 4367.07/mm2, superior = 23009.35/mm2 ± 5415.81/mm2, nasal = 22838.09/mm2 ± 4166.22/mm2, and inferior = 21097.53/mm2 ± 4235.84/mm2). A statistical significanceP<0.008was found between orthogonal meridians, that is, temporal, nasal48624.77/mm2>superior, inferior (44106.88/mm2). A drop in retinal sensitivity was observed as the eccentricity increasedP<0.05. It was also found that as cone packing density decreased retinal sensitivity also decreasedP<0.05in all quadrants. This was observed at both 2 and 3 degrees.Conclusion. It is of crucial importance to establish normative variations in cone structure-function correlation. This may help in detection of subtle pathology and its early intervention.

Evidence of photoreceptor migration during early foveal development: A quantitative analysis of human fetal retinae

1992 ◽  
Vol 8 (6) ◽  
pp. 505-514 ◽  
Author(s):  
Claudia Diaz Araya ◽  
Jan M. Provis
Keyword(s):  
Packing Density ◽  
Cresyl Violet ◽  
Cone Mosaic ◽  
Rods And Cones ◽  
Individual Variations ◽  
Mitotic Figures ◽  
Conventional Manner ◽  
Age Range ◽  
Cone Density ◽  
Packing Densities

AbstractWe have analyzed aspects of photoreceptor topography in wholemounts of human fetal retinae in the age range 13–24 weeks of gestation. Fetal retinae were stained with cresyl violet and the sizes and packing densities of rods and cones analyzed in the conventional manner.Cones and rods were present within a differentiating region, free of mitotic figures and approximately centered on the putative fovea, represented by the foveal cone mosaic. At 13 weeks of gestation the foveal cone mosaic was clearly differentiated, cone nuclei reaching a packing density of 14,200 per mm; a small number of rods were present in the immediately adjacent region. The packing densities of both rods and cones in these regions gradually increased and the area of the foveal cone mosaic gradually decreased throughout the age range sampled, although individual variations were evident. By 24 weeks of gestation, cone density was approximately 38,000 per mm in the foveal cone mosaic. The maximum rod density observed was 59,200 per mm in the region surrounding the foveal cone mosaic in a specimen of 20–21 weeks of gestation. In all specimens, maximum cone density occurred within the foveal cone mosaic and gradually declined towards the periphery of the differentiating region; a pronounced inverse relationship between cone soma diameter and packing density was also observed. The evidence strongly suggests that both rods and cones migrate centripetally, that is towards the center of the developing fovea, from early in development, possibly from the time that they first differentiate. The implications of these findings for fovealdevelopment are discussed.

scholarly journals Relación entre conducta prosocial, resolución de problemas y consumo de drogas en adolescentes

2016 ◽  
Vol 32 (2) ◽  
pp. 609 ◽  
Author(s):  
Olga Hernández-Serrano ◽  
José P. Espada ◽  
Alejandro Guillén-Riquelme
Keyword(s):  
Problem Solving ◽  
Statistical Significance ◽  
Cross Sectional Study ◽  
Prosocial Behaviour ◽  
Cross Sectional ◽  
Problem Solving Skills ◽  
Problem Solving Strategies ◽  
And Gender ◽  
Prosocial Behaviours ◽  
Age Range

<p>The objectives of the present study are the following ones: 1) to study the use of drugs, the prosocial behaviour and the problem-solving skills with respect to age and gender, and 2) to analyze the association of both the prosocial behaviour and the problem-solving skills with the use of drugs. An exploratory cross-sectional study was performed, amongst a sample of 567 students in Spanish Compulsory Secondary Education (48.14% males) with an age range from 14 to 17 years (<em>M </em>= 14.92; <em>SD </em>= 0.90). Statistically significant differences were found concerning alcohol use and the prosocial behaviour with respect to gender, as well as concerning alcohol and cannabis use with respect to age. Logistic regression analyses revealed statistical significance of the prosocial behaviour with respect to the use of alcohol and cannabis. The ability in problem-solving was the most important protective predictor with respect to the abuse of cannabis. The results from this study enhance the importance of tailored interventions based on the promotion of prosocial behaviours and/or problem-solving strategies as fundamental protective factors for substance use amongst adolescents.</p>

A Dynamic Route to Structure and Function: Recent Advances in Imine-Based Organic Nanostructured Materials

2013 ◽  
Vol 66 (1) ◽  
pp. 9 ◽  
Author(s):  
Yi Liu ◽  
Zhan-Ting Li
Keyword(s):  
Self Assembly ◽  
Reaction System ◽  
Functional Materials ◽  
Building Blocks ◽  
The Self ◽  
Interlocked Molecules ◽  
Functional Aspects ◽  
Imine Bond ◽  
And Function ◽  
Dynamic Route

The chemistry of imine bond formation from simple aldehyde and amine precursors is among the most powerful dynamic covalent chemistries employed for the construction of discrete molecular objects and extended molecular frameworks. The reversible nature of the C=N bond confers error-checking and proof-reading capabilities in the self-assembly process within a multi-component reaction system. This review highlights recent progress in the self-assembly of complex organic molecular architectures that are enabled by dynamic imine chemistry, including molecular containers with defined geometry and size, mechanically interlocked molecules, and extended frameworks and polymers, from building blocks with preprogrammed steric and electronic information. The functional aspects associated with the nanometer-scale features not only place these dynamically constructed nanostructures at the frontier of materials sciences, but also bring unprecedented opportunities for the discovery of new functional materials.

scholarly journals Relationship of Depression and function of Attention, Planning and Verbal Learning and Memory

2019 ◽  
Vol 8 (9) ◽  
pp. 214-225
Author(s):  
Nongmeikapam Premika Devi
Keyword(s):  
Learning And Memory ◽  
Verbal Learning ◽  
Education Level ◽  
Auditory Verbal Learning ◽  
And Function ◽  
Age Range ◽  
Relationship Of ◽  
The Relationship ◽  
Minimum Education ◽  
Hiv Aids

The present study examines the relationship of depression and the neuropsychologicalfunction of attention, planning and auditory verbal learning and memory among individualswith HIV/AIDS. 200 subjects who were HIV/AIDS positive (100 males and 100 females) andwere within age range of 20 to 50 years and minimum education level of 8th standard weretaken. The result indicates that Depression slows down the performance of attention; alsodepression most likely decreases the function of auditory verbal learning and memory

scholarly journals ULTRASOUND PREDICTABILITY OF LOWER UTERINE SEGMENT CESAREAN SECTION SCAR THICKNESS

2020 ◽  
pp. 9-11
Author(s):  
Madhu Kumari ◽  
Kumari Bibha ◽  
Abha Sinha ◽  
Debarshi Jana
Keyword(s):  
Cesarean Section ◽  
Gestational Age ◽  
Statistical Significance ◽  
P Value ◽  
Chi Square ◽  
Medical College ◽  
Chi Square Test ◽  
Uterine Scar ◽  
Age Range ◽  
The Given

Objective: The objective of this study is to find out association between scar thickness, assessed sonographically, and intraoperative findings (IOF). Study Design: Descriptive study. Place and Duration of Study: Department of Obstetrics and Gynecology, Sri Krishna Medical College and Hospital, Muzaffarpur, Bihar from June 2019 to May 2020. Methodology: A total of 70 pregnant patients were included in this study. Transabdominal ultrasound was done for scarred uteri. Sonographic findings were co-related with introperative findings. All the given data were entered on SPSS version 23. Age was expressed as mean ± SD. Parity, gestational age, and interval between cesarean sections were expressed as frequencies with percentages. Statistical analysis was done by using Chi-square test for categorical data for association between sonographic scar thickness and intraoperative findings. The statistical significance was set at p-value <0.05. Results: The age range of the patients was 20- 36 years with a mean of 27.91 ±3.690 years. Gestational age at the time of cesarean section was between 27-40 weeks of gestation with a mean of 37 ±2.126 weeks. The interval from previous cesarean was 10 months at the minimum, and 6 years at the maximum with a mean of 2.29 ±1.0 months. Mean scar thickness was 2.5 mm. Association between scar thickness (<1-3 mm) and intaoperative findings of dehiscence and rupture showed a p-value of <0.001. Conclusion: Sonographic assessment of a uterine scar has a practical application to determine the thickness of previous scar, and assess its integrity.

scholarly journals Assessing Developmental Environmental Risk Factor Exposure in Clinical High Risk for Psychosis Individuals: Preliminary Results Using the Individual and Structural Exposure to Stress in Psychosis-Risk States Scale

2019 ◽  
Vol 8 (7) ◽  
pp. 994
Author(s):  
Teresa Vargas ◽  
Denise S. Zou ◽  
Rachel E. Conley ◽  
Vijay A. Mittal
Keyword(s):  
Risk Factors ◽  
High Risk ◽  
Environmental Risk ◽  
Statistical Significance ◽  
Environmental Risk Factors ◽  
Group Differences ◽  
Clinical High Risk ◽  
Significant Group ◽  
Psychosis Risk ◽  
Age Range

Introduction: Exposure to cumulative environmental risk factors across development has been linked to a host of adverse health/functional outcomes. This perspective incorporating information regarding exposure at differing developmental periods is lacking in research surrounding individuals at Clinical High Risk (CHR) for developing a psychotic disorder. Methods: CHR individuals (n = 35) and healthy volunteers (n = 28) completed structured clinical interviews as well as our group’s newly developed Individual and Structural Exposure to Stress in Psychosis-risk-states (ISESP) interview. Lifetime cumulative scores were calculated, and severity of stress was reported for multiple developmental periods/ages. Group differences were tested, and associations with current symptom domains were examined. Results: Significant group differences were not observed for lifetime cumulative events, though CHR trended toward endorsing more events and greater stress severity. For stress severity across development, there were trending group differences for the 11–13 age range, and significant group differences for the 14–18 age range; notably, comparisons for earlier time points did not approach statistical significance. Associations between negative symptoms and cumulative severity of exposure were observed. Discussion: Results suggest exploring exposure to cumulative environmental risk factors/stressors and stress severity across developmental periods is generally informative and possibly specifically so for predictive models and diathesis-stress psychosis risk conceptualizations.

scholarly journals Tooth extraction: Pattern and etiology from extreme Northwestern Nigeria

2017 ◽  
Vol 11 (03) ◽  
pp. 335-339 ◽  
Author(s):  
Abdurrazaq Olanrewaju Taiwo ◽  
Adebayo Aremu Ibikunle ◽  
Ramat Oyebunmi Braimah ◽  
Omotayo Amidu Sulaiman ◽  
Olalekan Micah Gbotolorun
Keyword(s):  
Periodontal Disease ◽  
Tooth Extraction ◽  
Statistical Significance ◽  
Age Groups ◽  
Urban Region ◽  
Geographical Regions ◽  
Extraction Pattern ◽  
The Difference ◽  
And Gender ◽  
Age Range

ABSTRACT Objective: Tooth extraction is a commonly performed procedure in dental clinics. It has been shown that the reasons for and pattern of tooth extraction vary across geographical regions. Few reports on the pattern of extraction among a semi-urban populace exist. To the best of our knowledge, there is no study on the pattern and reasons for tooth mortality from Sokoto, Northwestern Nigeria, which is a semi-urban region. Materials and Methods: A review of the records of patients that had tooth extraction at our center between January 2009 and January 2016, was done. Data such as the age, gender, type of tooth extracted, and reasons for extraction were retrieved and analyzed. Cross tabulations for age and gender were also made. The level of statistical significance was set at P < 0.05. Results: A total of 1167 extractions were performed in 984 patients. An age range of 18–107 years with a mean (±standard deviation) of 34.8 (13.3) was observed. Most of the patients were in the 21–30 years age group accounting for 35.7% of cases. Dental caries and its sequelae (DCS) (631, 54.1%) were the most common reasons for extraction, followed by periodontal disease (192, 16.5%). The difference in proportions of reasons for tooth extraction between the gender was statistically significant (P = 0.02; df = 24). The difference in the reasons for extraction among the age groups was statistically significant (P < 0.001; df = 132). Conclusion: DCS along with periodontal disease were the major reasons for extractions. These are largely preventable causes of tooth extraction; therefore, there is a need for commencement of far-reaching preventative actions.

A study of Japanese back channels

1998 ◽  
Vol 15 ◽  
pp. 77-92
Author(s):  
Duck-Young Lee ◽  
Chiharu Mukai
Keyword(s):  
Native Speakers ◽  
Native Speaker ◽  
Advanced Level ◽  
Functional Aspects ◽  
Japanese Learners ◽  
And Function

Abstract This study presents findings from an analysis of the conversational data involving the Japanese back channel with special attention to the comparison of back channel behaviour between Japanese native speakers and Japanese learners at an advanced level. While the analysis is based on four aspects of the back channel (i.e. form, frequency, location and function), the study reveals that native speakers and Japanese learners show significant differences particularly in the locational and functional aspects. There were also trends that the native speaker tends to use back channels in a way of supporting and encouraging the learner to participate in the conversation.

scholarly journals Functional Aspects of Seminal Plasma in Bird Reproduction

2020 ◽  
Vol 21 (16) ◽  
pp. 5664
Author(s):  
Julian Santiago-Moreno ◽  
Elisabeth Blesbois
Keyword(s):  
Seminal Plasma ◽  
Ion Homeostasis ◽  
Sperm Concentration ◽  
Cellular Functions ◽  
Functional Aspects ◽  
Reproductive Techniques ◽  
Sperm Survival ◽  
Protein Components ◽  
And Function

This review provides an updated overview of the seminal plasma composition, and the role of metabolic and protein components on the sperm function of avian species. In addition, the implication of seminal plasma on assisted reproductive techniques of birds was discussed. The semen of birds usually has exceptionally high sperm concentration with relatively little seminal plasma, but this contributes to very fast changes in sperm metabolism and function. The biochemical characteristics and physiological roles of the various seminal plasma components in birds (carbohydrates, lipids, amino acids, hormones, and proteins) are poorly understood. Seminal plasma content of proteins has an action on most cellular functions: metabolism, immunity, oxido-reduction regulation, proteolysis, apoptosis, ion homeostasis, and antimicrobial defenses. The variable amount of many proteins is related to a different fertility capacity of poultry sperm. The role of seminal plasma on semen conservation (chilling and freezing) remains largely a matter of speculation, as both inhibitory and stimulating effects have been found. Whereas the presence of seminal plasma did not seem to affect the sperm survival after freezing–thawing, DNA fragmentation is lower in the absence of seminal plasma. The molecular basis of the influence of seminal plasma on sperm cryo-resistance was also discussed in the present review.

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