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111.
Samira Nuñez Velazquez Carlos Enrique Rumbold Sandra Mabel Obenat 《Marine Biology Research》2017,13(8):888-898
We studied the population dynamics and reproductive biology of Caprella dilatata and Caprella equilibra in order to provide the basis for understanding the ecological role of both species in Mar del Plata Harbour. Caprellids and organisms from the fouling community were obtained by sampling in the harbour, monthly from April 2014 to March 2015. Mean density of C. dilatata was homogeneous during most of the study period (ca. 50–200 ind/100?g) and reached their maximum in May (ca. 650 ind/100?g), while C. equilibra did not show any differences during the sampling period (ca. 30 ind/100?g). Juveniles of C. dilatata reached their highest densities in May, while ovigerous females were at their maximum values in late spring, summer and early autumn, and no correlation was found between seawater temperature and monthly density. On the other hand, C. equilibra reached its maximum juvenile and ovigerous female densities in summer, and showed a positive correlation with seawater temperature. Sex-ratio was female biased in C. dilatata, but in C. equilibra it was equal between sexes. The number of eggs carried by females was positively correlated to the size in both species. The present study suggests that the population dynamics of C. equilibra are intimately related to seawater temperature, while for C. dilatata no relationship was found. Future studies of ecology and behaviour traits in caprellid species are needed in order to determine the ecological role and the environmental factors that could affect both species. 相似文献
112.
Dr. Joseph E. Thomas Mabel Koshy Lillie Patterson Louise Dorn Kurian Thomas 《Applied psychophysiology and biofeedback》1984,9(4):413-420
Fifteen patients with a history of painful episodes of sickle cell disease were given training in progressive relaxation, thermal biofeedback, cognitive strategies, and self-hypnosis to help them develop self-management skills to relieve pain. Results show a 38.5% reduction in the number of emergency room visits, a 31% reduction in the number of hospitalizations, and a 50% reduction in the inpatient stay during the 6 months since the beginning of therapy compared to 6 months prior to therapy. Analgesic intake was reduced by 29% for those who were using it regularly. This is a preliminary study, and the results are considered only as suggestive of the potential use of biofeedback therapy and behavioral management in alleviating painful episodes in sickle cell disease.An earlier version of this paper was presented at the 6th Annual Convention of the American Association of Biofeedback Clinicians, Chicago, November 5, 1982. 相似文献
113.
On the macromolecular composition of the jelly coat from Strongylocentrotus purpuratus eggs 总被引:1,自引:0,他引:1
The number of macromolecular components present in the egg jelly coat of Strongylocentrotus purpuratus was investigated. The material was prepared free from egg contaminants and examined for homogeneity by cellulose acetate electrophoresis, disc gel electrophoresis, ultracentrifugation and immunological studies. The electrophoretic and ultracentrifugal studies showed the presence of at least two components. The two-dimensional immunodiffusion tests using rabbit antiserum against whole jelly coat, exhibited four and immunoelectrophoresis five different antigens. In addition, it was possible to separate two components from gel filtration experiments with Sepharose 4B. It is concluded therefore that the S. purpuratus egg jelly coat contains minimally from two to five macromolecules. 相似文献
114.
Mabel Enriquez-Algeciras Sanjoy K Bhattacharya 《World journal of biological chemistry》2013,4(4):102-110
Central and peripheral nervous systems are lipid rich tissues. Lipids, in the context of lipid-protein complexes, surround neurons and provide electrical insulation for transmission of signals allowing neurons to remain embedded within a conducting environment. Lipids play a key role in vesicle formation and fusion in synapses. They provide means of rapid signaling, cell motility and migration for astrocytes and other cell types that surround and play supporting roles neurons. Unlike many other signaling molecules, lipids are capable of multiple signaling events based on the different fragments generated from a single precursor during each event. Lipidomics, until recently suffered from two major disadvantages:(1) level of expertise required an overwhelming amount of chemical detail to correctly identify a vast number of different lipids which could be close in their chemical reactivity; and(2) high amount of purified compounds needed by analytical techniques to determine their structures. Advances in mass spectrometry have enabled overcoming these two limitations. Mass spectrometry offers a great degree of simplicity in identification and quantification of lipids directly extracted from complex biological mixtures. Mass spectrometers can be regarded to as mass analyzers. There are those that separate and analyze the product ion fragments in space(spatial) and those which separate product ions in time in the same space(temporal). Databases and standardized instrument parameters have further aided the capabilities of the spatial instruments while recent advances in bioinformatics have made the identification and quantification possible using temporal instruments. 相似文献
115.
Steps during the development of the zebrafish locomotor network. 总被引:1,自引:0,他引:1
Edna Brustein Louis Saint-Amant Robert R Buss Mabel Chong Jonathan R McDearmid Pierre Drapeau 《Journal of Physiology》2003,97(1):77-86
This review summarizes recent data from our lab concerning the development of motor activities in the developing zebrafish. The zebrafish is a leading model for studies of vertebrate development because one can obtain a large number of transparent, externally and rapidly developing embryos with motor behaviors that are easy to assess (e.g. for mutagenic screens). The emergence of embryonic motility was studied behaviorally and at the cellular level. The embryonic behaviors appear sequentially and include an early, transient period of spontaneous, alternating tail coilings, followed by responses to touch, and swimming. Patch clamp recording in vivo revealed that an electrically coupled network of a subset of spinal neurons generates spontaneous tail coiling, whereas a chemical (glutamatergic and glycinergic) synaptic drive underlies touch responses and swimming and requires input from the hindbrain. Swimming becomes sustained in larvae once serotonergic neuromodulatory effects are integrated. We end with a brief overview of the genetic tools available for the study of the molecular determinants implicated in locomotor network development in the zebrafish. Combining genetic, behavioral and cellular experimental approaches will advance our understanding of the general principles of locomotor network assembly and function. 相似文献
116.
Conspicuousness,color resemblance,and toxicity in geographically diverging mimicry: The pan‐Amazonian frog Allobates femoralis
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Adolfo Amézquita Óscar Ramos Mabel Cristina González Camilo Rodríguez Iliana Medina Pedro Ivo Simões Albertina Pimentel Lima 《Evolution; international journal of organic evolution》2017,71(4):1039-1050
Predation risk is allegedly reduced in Batesian and Müllerian mimics, because their coloration resembles the conspicuous coloration of unpalatable prey. The efficacy of mimicry is thought to be affected by variation in the unpalatability of prey, the conspicuousness of the signals, and the visual system of predators that see them. Many frog species exhibit small colorful patches contrasting against an otherwise dark body. By measuring toxicity and color reflectance in a geographically variable frog species and the syntopic toxic species, we tested whether unpalatability was correlated with between‐species color resemblance and whether resemblance was highest for the most conspicuous components of coloration pattern. Heterospecific resemblance in colorful patches was highest between species at the same locality, but unrelated to concomitant variation in toxicity. Surprisingly, resemblance was lower for the conspicuous femoral patches compared to the inconspicuous dorsum. By building visual models, we further tested whether resemblance was affected by the visual system of model predators. As predicted, mimic‐model resemblance was higher under the visual system of simulated predators compared to no visual system at all. Our results indicate that femoral patches are aposematic signals and support a role of mimicry in driving phenotypic divergence or mimetic radiation between localities. 相似文献
117.
Background
Infertility has been shown to have considerable psychological effects on the well-being of couples, especially women. Religion has been found as a resource used by infertile women to cope with their distress. Little research has examined the influence of religious coping on psychological distress among infertile women in Ghana. This study examines the relationship between positive and negative religious coping and psychological health for women with infertility problems in Ghana.Methods
One hundred and fifty married women who were receiving assisted reproduction care in two specialized clinics were recruited for this study. Participants were administered with the Brief Symptom Inventory and Brief Religious Coping Scale to assess psychological health associated with infertility and religious coping respectively. A hierarchical regression was performed to examine the relative contribution of the domains of psychological health (i.e. somatization, anxiety and depression) in predicting negative religious coping and positive religious.Results
The results showed that negative religious coping was significant and positively correlated with somatization, depression and anxiety. Furthermore, a positive relationship also existed between positive religious coping and somatization and anxiety but not depression. After controlling for age and duration of infertility, somatization and anxiety predicted positive religious coping whilst all the domains of psychological health (somatization, anxiety and depression) precited negative religious coping.Conclusions
This study expanded on the existing literature by examining positive and negative religious coping with psychological distress associated with infertility for women. These results underscore the need for health professionals providing therapies for women with infertility to acknowledge and consider their religious beliefs as this influences their mental health.118.
Carrie L. Woods Catherine L. Cardelús Peter Scull Alemayehu Wassie Mabel Baez Peter Klepeis 《Biodiversity and Conservation》2017,26(1):209-221
Many tropical forests worldwide are protected due to their sacredness to religious communities. In the south Gondar region of Ethiopia, most of the remaining native forests are tiny fragments (5.42 ha ± 0.34) surrounded by pasture and agriculture that are protected because they encompass churches of the Ethiopian Orthodox Tewahido Church (EOTC). A small number of communities have erected stone walls around the perimeter of the forests to demarcate the boundary, and/or protect the interior of the forest. We evaluated the effectiveness of these walls at protecting ecological conditions by examining tree and seedling communities among sacred forests with and without walls in Montane and Upper Montane sites. We found the wall to be an effective conservation tool as regeneration potential was higher in forests with a wall. The density and species richness of seedlings were significantly higher in forests with a wall and these effects were more pronounced in Upper Montane forests. Forests with a wall also had seedlings of many native tree species that were not found in forests without walls. As expected, there were few differences in tree communities in forests with and without a wall. Although rare on the landscape, the presence of a stone wall around these forests was effective at protecting the seedling community because it likely reduced access to the forests by grazers and directed human visitors to trails. The use of a stone wall may protect seedling communities in other sacred forest fragments, particularly for those that are small, isolated, surrounded by agriculture, and have a depleted seed bank. 相似文献
119.
Mabel C. Chou Chung-Piaw Teo Huan Zheng 《Flexible Services and Manufacturing Journal》2008,20(1-2):59-94
One of the most effective ways of minimizing supply/demand mismatch costs, with little increase in operational costs, is to deploy valuable resources in a flexible and timely manner to meet the realized demand. This notion of flexible processes has significantly changed operations in many manufacturing and service companies. For example, a flexible production system is now commonly used by automobile manufacturers, and a workforce cross-training system is now a common practice in many service industries. However, there is a trade-off between the level of flexibility available in the system and the associated complexity and operating costs. The challenge is to have the “right” level of flexibility to capture the bulk of the benefits from a fully flexible system, while controlling the increase in implementation costs. This paper reviews developments in process flexibility over the past decade. In particular, we focus on the phenomenon, often observed in practice, that a slight increase in process flexibility can lead to a significant improvement in system performance. This review explores the issues from three perspectives: design, evaluation, and applications. We also discuss how the concept of process flexibility has been deployed in several manufacturing and service systems. 相似文献
120.
Lance S. Evans Zella Kahn-Jetter Jessica Torres Mabel Martinez Paul Tarsia 《Trees - Structure and Function》2008,22(3):283-289
Land plants have evolved a large number of growth forms and each plant species has a unique morphology. For many tall plants,
main stems serve the function of vertical growth while primary and higher order branches are responsible for lateral growth
for greater light interception. Herein we search for a mechanical constant for primary branches. Primary branches were sampled
from 40 species of trees and shrubs. Among the species sampled, branch lengths ranged from 1.8 to 12.2 m, weights from 0.056
to 16.6 kg, base diameters from 17 to 150 mm, bending moments from 7.1 to 2,200 N-m, and section moduli from 0.039 to 29.0 × 10−3 m3. Primary branches of all 40 tree and shrub species exhibited relatively constant bending stresses along each branch. Moreover
stress values among the 40 species were relatively constant at about 11 MPa (mean = 11.1 MPa [range 5.2–18.9]; standard deviation = 3.3 MPa).
Furthermore, primary branches without secondary branches attached (1) had similar bending moment distributions as tapered
cantilever beams, (2) exhibited relatively constant slope values of stress versus length among all species (stresses increased
linearly with length), and (3) exhibited both relatively constant density and relatively constant taper within each species.
We conclude that the relatively constant stress of about 11 MPa of primary branches was due solely to the numbers, weights,
and distributions of secondary branches and associated higher order branches along primary branches for the 40 plant species.
To our knowledge, this is the first publication that shows a unifying mechanical constant for primary branches of plants.
相似文献
Lance S. EvansEmail: |