scholarly journals Metabarcoding hyperdiverse kelp holdfast communities on temperate reefs: An experimental approach to inform future studies

2021 ◽  
Author(s):  
Vanessa Arranz ◽  
Libby Liggins ◽  
J. David Aguirre
Keyword(s):  
Experimental Approach ◽  
Future Studies ◽  
Temperate Reefs ◽  
Kelp Holdfast

scholarly journals The Implementation of Online Accent Reduction Software to Improve Pronunciation of English and Arabic Department Students

2021 ◽  
Vol 3 (12) ◽  
pp. 26-37
Author(s):  
Nur Asmawati ◽  
Fitriningsih Fitriningsih
Keyword(s):  
Experimental Approach ◽  
English Department ◽  
Language Background ◽  
Future Studies ◽  
Significant Difference ◽  
English Pronunciation ◽  
Post Test ◽  
The Mean ◽  
Arabic Students ◽  
Accent Reduction

The objective of this study is to implement accent reduction software in English pronunciation teaching. This study employed an experimental approach. There were forty students recruited from the English and Arabic departments. The students were split into two classes, with one class being treated as an experimental class and another class as a controlled class. Each class consisted of twenty students, ten English department students, and the other ten Arabic department students. We administered an experimental class with twelve meeting treatments using the Elsa accent reduction software to teach English pronunciation. Meanwhile, the controlled class was not given any treatments.  The results show that there was a significant difference between the result of the pre-test and post-test of the students' pronunciations that were taught with the accent reduction software. It was found that the mean score of the experimental class was significantly improved from 53.12 to 85.44 after they were given the treatment. Meanwhile, the control group's mean score was also improved, but it was not significant from 49.33 to 59.11. Our study highlighted that the use of accent reduction software in teaching English pronunciations could help students to improve their English pronunciations. The students were able to imitate an English sound from the software. The limitation of this study is that we did not compare the results of English and Arabic students’ ability in pronunciations after the use of the software. Future studies are recommended to compare pronunciations between English and Arabic students through the use of the software to understand language background might affect the treatment.

scholarly journals STATE OF THE ART OF SCIENTIFIC LITERATURE ON Hancornia speciosa: TRENDS AND GAPS

2016 ◽  
Vol 38 (4) ◽  
Author(s):  
LUCIANE MADUREIRA DE ALMEIDA ◽  
CÁSSIA APARECIDA NOGUEIRA ◽  
PEDRO PAULINO BORGES ◽  
ANGÉLICA DAIANE LEMOS DO PRADO ◽  
PABLO JOSÉ GONÇALVES
Keyword(s):  
Experimental Approach ◽  
Scientific Literature ◽  
State Of The Art ◽  
Scientific Productivity ◽  
Natural Compounds ◽  
Future Studies ◽  
Conservation Projects ◽  
Pharmacological Potential ◽  
Hancornia Speciosa ◽  
Management And Conservation

ABSTRACT The economic and scientific interest in Hancornia speciosa (mangabeira) has been growing in recent years, mainly due to the marketing of fruit and extraction of natural compounds with high pharmacological potential. In this study, a scientometric survey about mangabeira was carried out in order to promote and direct future studies on the species. As a result, low scientific productivity associated with this species was found, with only 131 articles published in the last 69 years. In addition, this study identified some trends in bibliographic production on mangabeira, among them: the increasing number of articles over the years; scientific dissemination in nationwide journals; the main focus of this study is associated with agronomic studies; the experimental approach is more frequent and usually associated with populations of restricted geographical distribution; and the scientific production is mainly from education institutions. Furthermore, this study also allowed the identification of some gaps in knowledge about mangabeira, among them the difficulty in describing and characterizing botanical lines; lack of analysis of the genetic diversity of widely distributed populations; lack of management and conservation projects for the species; lack of description of cultivation, collection and preservation techniques of fruits; and lack of identification of natural compounds responsible for its pharmacological activity. It is expected that the data generated in this study will serve to direct future studies on H. speciosa.

scholarly journals Testing for context-dependent effects of maternal thyroid hormones on offspring survival and physiology: an experimental approach manipulating temperature in a wild bird species

2020 ◽  
Author(s):  
Bin-Yan Hsu ◽  
Tom Sarraude ◽  
Nina Cossin-Sevrin ◽  
Melanie Crombecque ◽  
Antoine Stier ◽  
...  
Keyword(s):  
Thyroid Hormones ◽  
Experimental Approach ◽  
Bird Species ◽  
Environmental Cues ◽  
Offspring Survival ◽  
Mitochondrial Density ◽  
Future Studies ◽  
Context Dependent ◽  
Maternal Thyroid ◽  
Full Factorial

AbstractMaternal effects via hormonal transfer from the mother to the offspring provide a tool to translate environmental cues to the offspring. Experimental manipulations of maternally transferred hormones have yielded increasingly contradictory results, which may be explained by environment-dependent effects of hormones. Yet context-dependent effects have rarely been experimentally tested. We therefore studied whether maternally transferred thyroid hormones (THs) exert context-dependent effects on offspring survival and physiology by manipulating both egg TH levels and post-hatching nest temperature in wild pied flycatchers (Ficedula hypoleuca) using a full factorial design. We found no clear evidence for context-dependent effects of prenatal THs related to postnatal temperature on growth, survival and potential underlying physiological responses (plasma TH levels, oxidative stress and mitochondrial density). We conclude that future studies should test for other key environmental conditions, such as food availability, to understand potential context-dependent effects of maternally transmitted hormones on offspring, and their role in adapting to changing environments.

scholarly journals How to test for phasic modulation of neural and behavioural responses

2019 ◽  
Author(s):  
Benedikt Zoefel ◽  
Matthew H Davis ◽  
Giancarlo Valente ◽  
Lars Riecke
Keyword(s):  
Experimental Approach ◽  
Neural Oscillations ◽  
Single Trial ◽  
Phase Effect ◽  
Optimal Method ◽  
Response Variable ◽  
Future Studies ◽  
Behavioural Responses ◽  
Matlab Code

AbstractResearch on whether perception or other processes depend on the phase of neural oscillations is rapidly gaining popularity. However, it is unknown which methods are optimally suited to evaluate the hypothesized phase effect. Using a simulation approach, we here test the ability of different methods to detect such an effect on dichotomous (e.g., “hit” vs “miss”) and continuous (e.g., scalp potentials) response variables. We manipulated parameters that characterise the phase effect or define the experimental approach to test for this effect. For each parameter combination and response variable, we identified an optimal method. We found that methods regressing single-trial responses on circular (sine and cosine) predictors perform best for all of the simulated parameters, regardless of the nature of the response variable (dichotomous or continuous). In sum, our study lays a foundation for optimized experimental designs and analyses in future studies investigating the role of phase for neural and behavioural responses. We provide MATLAB code for the statistical methods tested.

Experimental Determination of the Effective Resolution Limit in Thick Specimens at High Voltages

1975 ◽  
Vol 33 ◽  
pp. 664-665
Author(s):  
Mircea Fotino
Keyword(s):  
Experimental Approach ◽  
Chromatic Aberration ◽  
Resolving Power ◽  
Biological Research ◽  
Specimen Thickness ◽  
Resolution Limit ◽  
High Voltage Electron Microscopy ◽  
Voltage Electron ◽  
Resolution Level

The use of thick specimens (0.5 μm to 5.0 μm or more) is one of the most resourceful applications of high-voltage electron microscopy in biological research. However, the energy loss experienced by the electron beam in the specimen results in chromatic aberration and thus in a deterioration of the effective resolving power. This sets a limit to the maximum usable specimen thickness when investigating structures requiring a certain resolution level.An experimental approach is here described in which the deterioration of the resolving power as a function of specimen thickness is determined. In a manner similar to the Rayleigh criterion in which two image points are considered resolved at the resolution limit when their profiles overlap such that the minimum of one coincides with the maximum of the other, the resolution attainable in thick sections can be measured by the distance from minimum to maximum (or, equivalently, from 10% to 90% maximum) of the broadened profile of a well-defined step-like object placed on the specimen.

An Early Developmental Marker for Radial Glia in Rat Spinal Cord

1996 ◽  
Vol 54 ◽  
pp. 36-37
Author(s):  
V. Kriho ◽  
H.-Y. Yang ◽  
C.-M. Lue ◽  
N. Lieska ◽  
G. D. Pappas
Keyword(s):  
Spinal Cord ◽  
Intermediate Filament ◽  
Radial Glia ◽  
Rat Spinal Cord ◽  
Future Studies ◽  
Spinal Cord Development ◽  
Median Septum ◽  
Differentiation Marker ◽  
Early Developmental ◽  
Developing Rat

Radial glia have been classically defined as those early glial cells that radially span their thin processes from the ventricular to the pial surfaces in the developing central nervous system. These radial glia constitute a transient cell population, disappearing, for the most part, by the end of the period of neuronal migration. Traditionally, it has been difficult to definitively identify these cells because the principal criteria available were morphologic only.Using immunofluorescence microscopy, we have previously defined a phenotype for radial glia in rat spinal cord based upon the sequential expression of vimentin, glial fibrillary acidic protein and an intermediate filament-associated protein, IFAP-70/280kD. We report here the application of another intermediate filament-associated protein, IFAP-300kD, originally identified in BHK-21 cells, to the immunofluorescence study of radial glia in the developing rat spinal cord.Results showed that IFAP-300kD appeared very early in rat spinal cord development. In fact by embryonic day 13, IFAP-300kD immunoreactivity was already at its peak and was observed in most of the radial glia which span the spinal cord from the ventricular to the subpial surfaces (Fig. 1). Interestingly, from this time, IFAP-300kD immunoreactivity diminished rapidly in a dorsal to ventral manner, so that by embryonic day 16 it was detectable only in the maturing macroglial cells in the marginal zone of the spinal cord and the dorsal median septum (Fig. 2). By birth, the spinal cord was essentially immuno-negative for this IFAP. Thus, IFAP-300kD appears to be another differentiation marker available for future studies of gliogenesis, especially for the early stages of radial glia differentiation.

Autophagy and ageing: implications for age-related neurodegenerative diseases

2013 ◽  
Vol 55 ◽  
pp. 119-131 ◽  
Author(s):  
Bernadette Carroll ◽  
Graeme Hewitt ◽  
Viktor I. Korolchuk
Keyword(s):  
Neurodegenerative Diseases ◽  
Energy Availability ◽  
Future Studies ◽  
Intracellular Degradation ◽  
Age Related ◽  
Autophagy Induction ◽  
Social Importance ◽  
Cellular Dysfunction ◽  
Autophagy Activity ◽  
Intense Research

Autophagy is a process of lysosome-dependent intracellular degradation that participates in the liberation of resources including amino acids and energy to maintain homoeostasis. Autophagy is particularly important in stress conditions such as nutrient starvation and any perturbation in the ability of the cell to activate or regulate autophagy can lead to cellular dysfunction and disease. An area of intense research interest is the role and indeed the fate of autophagy during cellular and organismal ageing. Age-related disorders are associated with increased cellular stress and assault including DNA damage, reduced energy availability, protein aggregation and accumulation of damaged organelles. A reduction in autophagy activity has been observed in a number of ageing models and its up-regulation via pharmacological and genetic methods can alleviate age-related pathologies. In particular, autophagy induction can enhance clearance of toxic intracellular waste associated with neurodegenerative diseases and has been comprehensively demonstrated to improve lifespan in yeast, worms, flies, rodents and primates. The situation, however, has been complicated by the identification that autophagy up-regulation can also occur during ageing. Indeed, in certain situations, reduced autophagosome induction may actually provide benefits to ageing cells. Future studies will undoubtedly improve our understanding of exactly how the multiple signals that are integrated to control appropriate autophagy activity change during ageing, what affect this has on autophagy and to what extent autophagy contributes to age-associated pathologies. Identification of mechanisms that influence a healthy lifespan is of economic, medical and social importance in our ‘ageing’ world.

Mesophyll conductance: the leaf corridors for photosynthesis

2020 ◽  
Vol 48 (2) ◽  
pp. 429-439 ◽  
Author(s):  
Jorge Gago ◽  
Danilo M. Daloso ◽  
Marc Carriquí ◽  
Miquel Nadal ◽  
Melanie Morales ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Current Knowledge ◽  
Main Role ◽  
Mesophyll Conductance ◽  
Future Studies ◽  
Cell Structures ◽  
Leaf Tissues ◽  
Change Framework ◽  
Chloroplast Stroma

Besides stomata, the photosynthetic CO2 pathway also involves the transport of CO2 from the sub-stomatal air spaces inside to the carboxylation sites in the chloroplast stroma, where Rubisco is located. This pathway is far to be a simple and direct way, formed by series of consecutive barriers that the CO2 should cross to be finally assimilated in photosynthesis, known as the mesophyll conductance (gm). Therefore, the gm reflects the pathway through different air, water and biophysical barriers within the leaf tissues and cell structures. Currently, it is known that gm can impose the same level of limitation (or even higher depending of the conditions) to photosynthesis than the wider known stomata or biochemistry. In this mini-review, we are focused on each of the gm determinants to summarize the current knowledge on the mechanisms driving gm from anatomical to metabolic and biochemical perspectives. Special attention deserve the latest studies demonstrating the importance of the molecular mechanisms driving anatomical traits as cell wall and the chloroplast surface exposed to the mesophyll airspaces (Sc/S) that significantly constrain gm. However, even considering these recent discoveries, still is poorly understood the mechanisms about signaling pathways linking the environment a/biotic stressors with gm responses. Thus, considering the main role of gm as a major driver of the CO2 availability at the carboxylation sites, future studies into these aspects will help us to understand photosynthesis responses in a global change framework.

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