Structure and electrical properties of eye muscles in cave- and surface-dwelling crayfishes

1980 ◽  
Vol 84 (1) ◽  
pp. 187-199
Author(s):  
D. Mellon ◽  
G. Lnenicka
Keyword(s):  
Input Resistance ◽  
Selective Advantage ◽  
Oculomotor System ◽  
Membrane Resistance ◽  
Muscle Fibres ◽  
Cross Sectional ◽  
Eye Muscles ◽  
Current Voltage ◽  
The Difference ◽  
Cave Dweller

The morphologies and passive electrical parameters of fibres in two eye muscles of a surface- and a cave-dwelling crayfish were compared. In the cave-dwelling form the muscles contained fewer fibres, of less diameter, and hence had a smaller cross-sectional area. Current-voltage relationships were similar in both species. Input resistance was higher in the cave-dweller, but the difference was not as great as would be expected on the basis of geometry alone. Accordingly, the specific membrane resistance of muscle fibres in the cave-dweller is 50–60% smaller than that in the surface-dweller. This may account partially for the observation that identified excitatory junctional potentials in muscles of cave- and surface dwellers have similar amplitudes. We conclude that a functional oculomotor system is maintained in cave-dwelling crayfish, and that this system confers some positive selective advantage.

Growth equations for skeletal muscle derived from the cytonuclear ratio and growth constraining supplementary functions

1999 ◽  
Vol 68 (1) ◽  
pp. 129-140 ◽  
Author(s):  
C. Z. Roux
Keyword(s):  
Muscle Mass ◽  
Whole Body ◽  
Muscle Fibres ◽  
Cell Nuclei ◽  
Cross Sectional ◽  
Body Protein ◽  
Mass Growth ◽  
Growth Constraints ◽  
The Difference ◽  
Almost All

AbstractFor purely hypertrophic muscle it is postulated that the growth rate in number of nuclei is proportional to the cytoplasmic mass per nucleus multiplied by a growth constraining supplementary function. Growth constraint depends on the distance from any one of the limit number of nuclei, the limit muscle mass or the limit cytoplasmic mass per nucleus. Furthermore, theory and evidence are presented for a power (allometric) relationship between total number of nuclei (n) and muscle mass (m) given by the equation n = gmh. Evidence points to two clusters of values for h, one in the vicinity of h = 2/3 and the other h = 1/2. Both may depend on a linear relationship between number of nuclei inside muscle fibre and fibre cross-sectional area. The difference between the two situations can be derived from basic assumptions on either local or systemic diffusion mediated control of the number or division of satellite cell nuclei, leading directly to values of h either equal to 2/3 or V2. For likely values of h and suitable choices of growth constraints, almost all well known growth functions in the literature are derived as potentially applicable to total number of nuclei, or muscle mass or their ratio. Muscle mass growth will show a sigmoidal form for h = 1. This explains sigmoidal growth in body mass as it is mostly dominated by muscle mass. A possible linear growth phase before maturity is explicable from the cessation of either length (h = 1) or nuclear (h = 0) growth in muscle fibres, while cytoplasmic growth continues to maturity. Furthermore, two rat examples indicate that whole body protein growth can be described by the equations derived for muscle mass growth.

Local differences in myotendinous junctions in axial muscle fibres of carp (Cyprinus carpio L.)

1996 ◽  
Vol 199 (4) ◽  
pp. 825-833
Author(s):  
I L Y Spierts ◽  
H A Asker ◽  
I H C Voss ◽  
J W M Osse
Keyword(s):  
Cyprinus Carpio ◽  
Myotendinous Junction ◽  
Muscle Fibres ◽  
Cross Sectional ◽  
Stress Load ◽  
Fibre Area ◽  
Axial Muscle ◽  
Carp Cyprinus Carpio ◽  
The Difference ◽  
Myotendinous Junctions

We studied the myotendinous junctions of anterior and posterior red and white axial muscle fibres of carp using stereology. In posterior axial muscle fibres of swimming fish, stress (load on the myotendinous junction) must be higher than in anterior fibres as posterior fibres have a longer phase of eccentric activity. As we expected the magnitude of the load on the junction to be reflected in its structure, we compared the interfacial ratio, the ratio between the area of the junctional sarcolemma and the cross-sectional fibre area, of these muscle fibres. This ratio differed significantly between the investigated groups, with red fibres and posterior fibres having the larger ratios. The higher interfacial ratio of posterior myotendinous junctions is in accordance with the proposition mentioned above. The difference between myotendinous junctions of red and white fibres is probably related to a difference in the duration of the load on the junction.

Thermal dependence of passive electrical properties of lizard muscle fibres

1987 ◽  
Vol 133 (1) ◽  
pp. 169-182 ◽  
Author(s):  
B. A. Adams
Keyword(s):  
Electrical Properties ◽  
Input Resistance ◽  
Membrane Resistance ◽  
Effect Of Temperature ◽  
Muscle Fibres ◽  
Thermal Dependence ◽  
Thermophilic Species ◽  
Length Constant ◽  
Increasing Temperature ◽  
Passive Electrical Properties

1. The thermal dependence of passive electrical properties was determined for twitch fibres from the white region of the iliofibularis (IF) muscle of Anolis cristatellus (15–35 degrees C) and Sceloporus occidentalis (15–40 degrees C), and for twitch fibres from the white (15–45 degrees C) and red (15–40 degrees C) regions of the IF of Dipsosaurus dorsalis. These species differ in thermal ecology, with Anolis being the least thermophilic and Dipsosaurus the most thermophilic. 2. Iliofibularis fibres from the three species reacted similarly to changing temperature. As temperature was increased, input resistance (Rin) decreased (average R10 = 0.7), length constant (L) decreased (average R10 = 0.9), time constant (tau) decreased (average R10 = 0.8), sarcoplasmic resistivity (Rs) decreased (average R10 = 0.8) and apparent membrane resistance (Rm) decreased (average R10 = 0.7). In contrast, apparent membrane capacitance (Cm) increased with increasing temperature (average R10 = 1.3). 3. Rin, L, tau and apparent Rm were lowest in fibres from Anolis (the least thermophilic species) and highest in fibres from Dipsosaurus (the most thermophilic species). Anolis had the largest and Dipsosaurus the smallest diameter fibres (126 and 57 micron, respectively). Apparent Cm was highest in fibres from Sceloporus, which had fibres of intermediate diameter (101 micron). Rs did not differ significantly among species. 4. The effect of temperature on the passive electrical properties of these lizard fibres was similar to that reported for muscle fibres from other ectothermic animals (crustaceans, insects, fish and amphibians) but qualitatively different from that reported for some mammalian (cat tenuissimus, goat intercostal) fibres. The changes that occur in the passive electrical properties render the fibres less excitable as temperature increases.

Perceived social support and burden of care of male and female caregivers of patient with schizophrenia

2017 ◽  
Vol 8 (1) ◽  
pp. 10
Author(s):  
Narendra Kumar Singh ◽  
Nishant Goyal
Keyword(s):  
Social Support ◽  
Perceived Social Support ◽  
Family Members ◽  
Well Being ◽  
Cross Sectional Study ◽  
Burden Of Care ◽  
Cross Sectional ◽  
Male And Female ◽  
The Social ◽  
The Difference

Background: Schizophrenia is associated with a high familial, social and economic burden. Schizophrenia is also associated with a high level of disability which may create impediments on the social and economic areas of the patients as well as on their respective family networks. Families with schizophrenia may encounter problems such as impairment of health and well being of other family members, restriction of social activities of the family members and shrinking of support from the social network. Aims: The present study examined the difference in perceived social support and burden of care between the male and female caregivers of patients with schizophrenia. Methods: This was a cross-sectional study examining the difference in perceived social support and burden of care between the male and female caregivers of patients with schizophrenia. The sample consisted of 60 (30 male and 30 female) caregivers of the patients with the diagnosis of schizophrenia as per ICD-10-DCR. Results and Conclusion: This study revealed that male caregivers perceived more social support and less burden of care as compared to female caregivers. Key words: Gender, social support, burden

Perbedaan Penggunaan Antikoagulan K2EDTA DAN K3EDTA Terhadap Hasil Pemeriksaan Indeks Eritrosit

2018 ◽  
Vol 1 (2) ◽  
pp. 114
Author(s):  
Wahdaniah Wahdaniah ◽  
Sri Tumpuk
Keyword(s):  
Screening Test ◽  
Venous Blood ◽  
The Body ◽  
Ethylene Diamine ◽  
P Value ◽  
Cross Sectional ◽  
Significant Difference ◽  
Ethylene Diamine Tetra Acetate ◽  
The Difference ◽  
Index Value

Abstract: Routine blood examination is the earliest blood test or screening test to determine the diagnosis of an abnormality. Blood easily froze if it is outside the body and can be prevented by the addition of anticoagulants, one of which Ethylene Diamine Tetra Acetate (EDTA). Currently available vacuum tubes containing EDTA anticoagulants in the form of K2EDTA and K3EDTA. K3EDTA is usually a salt that has better stability than other EDTA salts because it shows a pH approaching a blood pH of about 6.4. The purpose of this research is to know the difference of erythrocyte index results include MCH, MCV and MCHC using K3EDTA anticoagulant with K2EDTA. This research is a cross sectional design. This study used venous blood samples mixed with K2EDTA anticoagulant and venous blood mixed with K3EDTA anticoagulants, each of 30 samples. Data were collected and analyzed using paired different test. Based on data analysis that has been done on MCH examination, p value <0,05 then there is a significant difference between samples with K3EDTA anticoagulant with K2EDTA to erythrocyte index value. Then on the examination of MCV and MCHC obtained p value <0.05 then there is no significant difference between samples with K3EDTA anticoagulant with K2EDTA to erythrocyte index value.Abstrak: Pemeriksaan darah rutin merupakan pemeriksaan darah yang paling awal atau screening test untuk mengetahui diagnosis suatu kelainan. Darah mudah membeku jika berada diluar tubuh dan bisa dicegah dengan penambahan antikoagulan, salah satunya Ethylene Diamine Tetra Acetate (EDTA). Dewasa ini telah tersedia tabung vakum yang sudah berisi antikoagulan EDTA dalam bentuk  K2EDTA dan  K3EDTA. K3EDTA  biasanya berupa garam yang mempunyai stabilitas yang lebih baik dari garam EDTA yang lain karena menunjukkan pH yang mendekati pH darah yaitu sekitar 6,4. Tujuan dari penelitian ini adalah untuk mengetahui perbedaan hasil indeks eritrosit meliputi MCH, MCV dan MCHC menggunakan antikoagulan K3EDTA dengan K2EDTA. Penelitian ini merupakan penelitian dengan desain cross sectional. Penelitian ini menggunakan sampel darah vena yang dicampur dengan antikoagulan K2EDTA dan darah vena yang dicampur dengan antikoagulan K3EDTA, masing-masing sebanyak 30 sampel. Data dikumpulkan dan dianalisis menggunakan uji beda berpasangan. Berdasarkan analisis data yang telah dilakukan pada pemeriksaan MCH didapatkan nilai p < 0,05 maka ada perbedaan yang signifikan antara sampel dengan antikoagulan K3EDTA dengan K2EDTA terhadap nilai indeks eritrosit. Kemudian pada pemeriksaan MCV dan MCHC didapatkan nilai p < 0,05 maka tidak ada perbedaan yang signifikan antara sampel dengan antikoagulan K3EDTA dengan K2EDTA terhadap nilai indeks eritrosit.

Hepatitis A Seroprevalence Among Patients with Chronic Hepatitis B Infection: A Cross-Sectional Study in Iran During 2016-2017

2020 ◽  
Vol 20 (5) ◽  
pp. 748-751
Author(s):  
Seyed Ali Dehghan Manshadi ◽  
Neda Alijani ◽  
Mohammadreza Salehi ◽  
Omid Dadras ◽  
SeyedAhmad SeyedAlinaghi ◽  
...  
Keyword(s):  
Chronic Hepatitis ◽  
Hepatitis B ◽  
Chronic Hepatitis B ◽  
Hepatitis A ◽  
Cross Sectional Study ◽  
University Hospital ◽  
Cross Sectional ◽  
Reasonable Approach ◽  
The Difference ◽  
Prevention Method

Introduction: The aim of this study was to determine the prevalence of exposure to hepatitis A by means of serologic markers in chronic hepatitis B patients, with the secondary aim of finding the best prevention method for hepatitis A infection in susceptible groups of our setting. Methods: During the period between 2016 and 2017, we recruited 403 hepatitis B patients aged more than 14 years and regularly attending the infectious diseases clinic at a referral university hospital, Tehran, Iran. A blood sample was collected from all the patients and tested for hepatitis A IgG. The data was analyzed by SPSS v.19. Results: Although none of the patients had previously received hepatitis A vaccine, the results for serologic level of hepatitis A IgG, demonstrated positive results in 379 (94%) cases. The mean age of patients with negative and positive IgG was 29.17 and 42.46 years, respectively; the difference was statistically significant (P≤0.001). The majority of seronegative patients were young adults aged < 25 years and 25 to 35 years (P <0.001). Conclusion: Seroprevalence of hepatitis A in chronic HBV patients in Iran is high. As HBV infected patients younger than 35 years could be seronagative for HAV infection, evaluation of these patients for HAV infection and vaccination of seronegative patients would be a reasonable approach.

The Degree of Subjective Complaints of Students Practice in Mechanical Technology Laboratories

2018 ◽  
Vol 4 (1) ◽  
pp. 22
Author(s):  
I Ketut Widana
Keyword(s):  
Engineering Students ◽  
Standing Position ◽  
Statistical Test ◽  
Rank Test ◽  
Cross Sectional ◽  
Signed Rank ◽  
Before And After ◽  
Signed Rank Test ◽  
The Difference ◽  
Paired T Test

The working practice of the engineering students is part of the learning process that is irreducible and indispensable. The composition of  lecturing between theoretical and practical one is 40% to 60%. With this condition, the students spend more time at the laboratory. Generally, the students perform in the laboratory work by standing position. The design of research is observational cross-sectional. The method applied is observation, interview and measuring. The subjects of research are practicing students amounting to 21 students. Referring to the analysis of statistical test or Wilcoxon signed ranks test, the difference of effect of work position is significant, namely p < 0.05 towards musculoskeletal disorders (MSDs) before and after working. The quantity of the average complaint after working is score 44.62 ± 9.47. The result of Wilcoxon signed rank test shows that there is significant different effects of standing work position, namely p < 0.05 towards fatigue generally before and after working. The degree of the working pulse is on the average of 110.78  ± 17.80 bpm (beats per minutes) which can be categorized into the medium workload. Using paired t-test, the result is p < 0.05.

Quality of life in Hungarian polio survivors

2021 ◽  
Author(s):  
Erika Viktória Miszory ◽  
Melinda Járomi ◽  
Annamária Pakai
Keyword(s):  
Quality Of Life ◽  
Mental Health ◽  
Sample Selection ◽  
Cross Sectional Study ◽  
Two Dimensions ◽  
Cross Sectional ◽  
Emotional Role ◽  
The Difference ◽  
Polio Survivors

Abstract Aim The number of Hungarian polio patients can be estimated at approximately 3000. Polio infection is currently affecting people 56–65 years of age. The aim of the study was to reveal the quality of life of patients living with polio virus in Hungary. Subject and methods The quantitative cross-sectional study was conducted in January–April 2017 among polyomyelitis patients living in Hungary. In the non-random, targeted, expert sample selection, the target group was composed of patients infected with poliovirus (N = 268). We have excluded those who refused to sign the consent statement. Our data collection method was an SF-36 questionnaire. Using the IBM SPSS Statistics Version 22 program, descriptive and mathematical statistics (χ2-test) were calculated (p < 0.05). Results The mean age of the members of the examined population is 63.5 years; 68.1% were women and 31.90% were men. The majority of the respondents were infected by the polyovirus in 1956 (11.9%), 1957 (24.3%), and 1959 (19.5%). Polio patients, with the exception of two dimensions (mental health, social operation), on the scale of 100 do not reach the “average” quality of life (physical functioning 23 points, functional role 36 points, emotional role 47 points, body pain 48 points, general health 42 points, vitality 50 points, health change 31 points). Conclusion The quality of life of polio patients is far below the dimensions of physical function, while the difference in mental health compared to healthy people is minimal. It would be important to educate health professionals about the existing disease, to develop an effective rehabilitation method.

scholarly journals The Pandemic and Changes in the Self-Perception of Teacher Digital Competences of Infant Grade Students: A Cross Sectional Study

2021 ◽  
Vol 18 (9) ◽  
pp. 4756
Author(s):  
Rosalía Romero-Tena ◽  
Carmen Llorente-Cejudo ◽  
María Puig-Gutiérrez ◽  
Raquel Barragán-Sánchez
Keyword(s):  
Intervention Group ◽  
Cross Sectional Study ◽  
Self Perception ◽  
Digital Competence ◽  
Cross Sectional ◽  
Self Perceptions ◽  
Group A ◽  
Different Dimensions ◽  
The Difference ◽  
Group B

Without having a reaction time, the pandemic has caused an unprecedented transformation in universities around the world, leading to a revolution from structured models anchored in the conception of transmission of training towards a teaching approach-learning saved thanks to the incorporation of technology. This study aims to verify whether the pandemic situation has influenced the digital competence self-perception of students. Comparing two groups during the academic years 2019/2020 and 2020/2021, the instrument used is the questionnaire for digital competence “DigCompEdu Check-In” for future teachers. After the educational intervention, group A (before COVID-19) presented higher self-perceptions of competence than group B (during COVID-19); the pandemic situation caused by COVID-19 has negatively influenced students’ self-perception of their digital skills in the pretest in the different dimensions under study. Before receiving the training, the group that did not experience the pandemic enjoyed a higher self-perception of their competencies than the group that experienced the pandemic. The data obtained indicate that the difference exists, and that it is statistically significant, and may be a consequence of the clear relationship between self-perception and the way in which students face reality through their personal and subjective vision.

scholarly journals Effect of Leukoreduction on Hematobiochemical Parameters and Storage Hemolysis in Canine Whole Blood Units

Animals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 925
Author(s):  
Maria Teresa Antognoni ◽  
Maria Luisa Marenzoni ◽  
Ambra Lisa Misia ◽  
Luca Avellini ◽  
Elisabetta Chiaradia ◽  
...  
Keyword(s):  
Whole Blood ◽  
Complete Blood Count ◽  
Membrane Resistance ◽  
Progressive Increase ◽  
Rbc Membrane ◽  
Morphological Index ◽  
The Difference ◽  
Hematobiochemical Parameters ◽  
And Storage ◽  
Individual Donor

Storage lesions (SLs) occur when the red blood cell quality is altered during the preservation of blood units. Pre-storage leukoreduction would limit the number of SLs. The aims of this study were to evaluate the effectiveness of a leukoreduction filter for human use and the effect of pre-storage leukoreduction on some ematobiochemical parameters in stored canine whole blood. Seven canine blood units were tested. Each one was divided into two units—one leukoreduced (LRWB) and one non-leukoreduced (nLRWB). On each unit, we determined the complete blood count (CBC), lactate-dehydrogenase (LDH), electrolytes (Na+, K+, Cl−), morphological index (MI) and hemolysis, on storage days 0, 7, 14, 21, 28, 35, and 42. Leukoreduction allowed a 98.30% recovery of the RBC count, retaining 99.69% and 94.91% of WBCs and PLTs, respectively. We detected a significant increase of LDH and MI with strongly higher values in nLRWB compared to LRWB. A progressive increase in electrolytes and LDH concentrations was observed as indices of stored hemolysis. LDH showed significantly lower values in LRWB units compared to nLRWB, suggesting its release from leukocytes. In the majority of units, hemolysis reached 1% on the 42nd day of storage. We assert the human leukoreduction filter effectiveness on canine whole blood, and we recommend using nLRWB before day 14, especially for critically ill patients. The difference of the basal hemolysis (day 0) percentages observed between subjects suggests that more studies should be performed to confirm a possible inter-individual donor biological variability of RBC membrane resistance, as happens in humans.

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