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scholarly journals On Some Problems of Estimating Fundamental Niche from Physiological Data

2019 ◽  
Author(s):  
Gutiérrez-Ruelas Jesús Salvador ◽  
Laura Jiménez ◽  
Ana Patricia Quiroz-Reyes ◽  
Sabrina Cherizar Sotelo-Pedroza ◽  
Soberon Jorge

AbstractHutchinson proposed the idea of the fundamental niche, determined by physiological properties of a species, more than 50 years ago. The idea remains both central to ecological thinking and largely unexplored experimentally. In this note, we describe some problems of using physiological experiments databases to estimate fundamental niches, show some solutions, and the apply our solution to testing the prediction that fundamental niches contain realized niches, for some species of marine fishes and terrestrial beetles. Our results were concordant with Hutchinson’s predictions.

Oryx ◽  
2015 ◽  
Vol 50 (3) ◽  
pp. 437-445 ◽  
Author(s):  
Hai Ren ◽  
Hong Liu ◽  
Jun Wang ◽  
Lianlian Yuan ◽  
Xiaodong Cui ◽  
...  

AbstractThe distribution of the Critically Endangered tree Manglietia longipedunculata, of which there are only 11 known wild individuals, is restricted to the Nankunshan Nature Reserve in South China. The species is threatened with extinction because of its small number of individuals and the impediments to its reproduction (a combination of protogyny, a short period of stigma receptivity, and a lack of efficient pollinators). To reduce the risk of extinction we conducted two conservation translocation trials: one to augment the sole extant population, and the other 202 km north of the current range. The latter trial was a conservation introduction in which the goals were to increase the population and to buffer against the effects of climate change. We used emerged and grafted seedlings as translocation materials. We compared the survival, growth, and eco-physiological properties of emerged and grafted seedlings at the two sites. The survival rate and growth were higher for grafted seedlings than for emerged seedlings at both sites. Eco-physiological data indicated that grafted seedlings at both sites were as efficient or more so in light and water usage than wild individuals, whereas emerged seedlings were less efficient. Grafted seedlings attained the flowering stage sooner than emerged seedlings. Our study suggests that grafting can facilitate the augmentation and establishment of new populations of M. longipedunculata and perhaps of new populations of other threatened species facing reproductive difficulties and climate change.


2021 ◽  
Author(s):  
Jason Matthiopoulos

ABSTRACTFor 70 years, the fundamental niche, the complete set of environments that allow an individual, population, or species to persist, has shaped ecological thinking. Yet, its properties have eluded quantification, particularly for mobile, cognitively complex organisms. Here, I derive a concise mathematical equation for the fundamental niche and fit it to population growth and distribution data. I find that, within traditionally defined environmental spaces, habitat heterogeneity and behavioural plasticity make the fundamental niche more complex and malleable, but also more predictable, than previously envisaged. This important re-evaluation restores the fundamental niche as a cornerstone of ecological theory and promotes it as a central tool for applied ecology. It quantifies how organisms buffer themselves from change by bending the boundaries of viable environmental space, and offers a framework for designing optimal habitat interventions to protect biodiversity or obstruct invasive species.ONE-SENTENCE SUMMARYThe fundemental niche of animal species


Sensors ◽  
2019 ◽  
Vol 19 (20) ◽  
pp. 4561 ◽  
Author(s):  
Jungryul Seo ◽  
Teemu H. Laine ◽  
Kyung-Ah Sohn

In recent years, affective computing has been actively researched to provide a higher level of emotion-awareness. Numerous studies have been conducted to detect the user’s emotions from physiological data. Among a myriad of target emotions, boredom, in particular, has been suggested to cause not only medical issues but also challenges in various facets of daily life. However, to the best of our knowledge, no previous studies have used electroencephalography (EEG) and galvanic skin response (GSR) together for boredom classification, although these data have potential features for emotion classification. To investigate the combined effect of these features on boredom classification, we collected EEG and GSR data from 28 participants using off-the-shelf sensors. During data acquisition, we used a set of stimuli comprising a video clip designed to elicit boredom and two other video clips of entertaining content. The collected samples were labeled based on the participants’ questionnaire-based testimonies on experienced boredom levels. Using the collected data, we initially trained 30 models with 19 machine learning algorithms and selected the top three candidate classifiers. After tuning the hyperparameters, we validated the final models through 1000 iterations of 10-fold cross validation to increase the robustness of the test results. Our results indicated that a Multilayer Perceptron model performed the best with a mean accuracy of 79.98% (AUC: 0.781). It also revealed the correlation between boredom and the combined features of EEG and GSR. These results can be useful for building accurate affective computing systems and understanding the physiological properties of boredom.


2016 ◽  
Vol 115 (1) ◽  
pp. 240-254 ◽  
Author(s):  
Matthew J. Crossley ◽  
Jon C. Horvitz ◽  
Peter D. Balsam ◽  
F. Gregory Ashby

The basal ganglia are a collection of subcortical nuclei thought to underlie a wide variety of vertebrate behavior. Although a great deal is known about the functional and physiological properties of the basal ganglia, relatively few models have been formally developed that have been tested against both behavioral and physiological data. Our previous work (Ashby FG, Crossley MJ. J Cogn Neurosci 23: 1549–1566, 2011) showed that a model grounded in the neurobiology of the basal ganglia could account for basic single-neuron recording data, as well as behavioral phenomena such as fast reacquisition that constrain models of conditioning. In this article we show that this same model accounts for a variety of appetitive instrumental conditioning phenomena, including the partial reinforcement extinction (PRE) effect, rapid and slowed reacquisition following extinction, and renewal of previously extinguished instrumental responses by environmental context cues.


Swiss Surgery ◽  
2003 ◽  
Vol 9 (1) ◽  
pp. 3-7 ◽  
Author(s):  
Gervaz ◽  
Bühler ◽  
Scheiwiller ◽  
Morel

The central hypothesis explored in this paper is that colorectal cancer (CRC) is a heterogeneous disease. The initial clue to this heterogeneity was provided by genetic findings; however, embryological and physiological data had previously been gathered, showing that proximal (in relation to the splenic flexure) and distal parts of the colon represent distinct entities. Molecular biologists have identified two distinct pathways, microsatellite instability (MSI) and chromosomal instability (CIN), which are involved in CRC progression. In summary, there may be not one, but two colons and two types of colorectal carcinogenesis, with distinct clinical outcome. The implications for the clinicians are two-folds; 1) tumors originating from the proximal colon have a better prognosis due to a high percentage of MSI-positive lesions; and 2) location of the neoplasm in reference to the splenic flexure should be documented before group stratification in future trials of adjuvant chemotherapy in patients with stage II and III colon cancer.


2002 ◽  
Author(s):  
D. P. Jang ◽  
B. K. Wiederhold ◽  
S. B. McGehee ◽  
E. Durso ◽  
M. D. Wiederhold ◽  
...  

2020 ◽  
Vol 79 (3) ◽  
pp. 175-192
Author(s):  
AP Dineshbabu ◽  
PU Zacharia ◽  
T Sujitha ◽  
JK Shoba ◽  
KM Rajesh ◽  
...  
Keyword(s):  

2013 ◽  
Vol 26 (1 (special Issue)) ◽  
pp. 78-98
Author(s):  
Furhan T. Mhaisen ◽  
Najim R. Khamees ◽  
Atheer H. Ali
Keyword(s):  

2019 ◽  
Vol 57 (6) ◽  
pp. 665 ◽  
Author(s):  
Yen Thi Hoang ◽  
Quynh Thi Thu Tran ◽  
Ha Hoang Chu ◽  
Tuyen Thi Do ◽  
Thanh Tat Dang ◽  
...  

Purple nonsulfur bacteria are a group that has so much biotechnological applications, particularly in producing of functional food rich with unsaturated fatty acids. A purple nonsulfur bacterium (named HPB.6) was chosen based on its strong growth, high lipid and synthesis of unsaturated fatty acid (omega 6,7,9). Studying on basic biological characteristics showed that the cells of HPB.6 were observed as ovoid-rod shape, none motility, Gram negative staining. The diameter of single bacterium was about 0.8-1.0 µm. The cells divide by binary fission and had bacteriochlorophyll a (Bchl a). This bacterium grew well on medium with carbon and nitrogen sources such as acetate, succinate, pyruvate, butyrate, glutamate, arginine, leucine, tyrosine, alanine, methionine, threonine, glutamine, yeast extract and NH4Cl. This selected strain grew well on medium with salt concentrations from 1.5 - 6.0% (optimum 3%), pH from 5.0 to 8.0 (optimum at pH 6.5) and could withstand Na2S at 4.0 - 5.2 mM. Based on morphological, physiological properties and 16S rRNA analysis received demonstrated that HPB.6 strain belongs to the species Rhodovulum sulfidophilum.


2019 ◽  
Author(s):  
Michael Oschmann ◽  
Linus Johansson Holm ◽  
Oscar Verho

Benzofurans are everywhere in nature and they have been extensively studied by medicinal chemists over the years because of their chemotherapeutic and physiological properties. Herein, we describe a strategy that can be used to access elaborate benzo-2-carboxamide derivatives, which involves a synthetic sequence of 8-aminoquinoline directed C–H arylations followed by transamidations. For the directed C–H arylations, Pd catalysis was used to install a wide range of aryl and heteroaryl substituents at the C3 position of the benzofuran scaffold in high efficiency. Directing group cleavage and further diversification of the C3-arylated benzofuran products were then achieved in a single synthetic operation through the utilization of a two-step transamidation protocol. By bocylating the 8-aminoquinoline amide moiety of these products, it proved possible to activate them towards aminolysis with different amine nucleophiles. Interestingly, this aminolysis reaction was found to proceed efficiently without the need of any additional catalyst or additive. Given the high efficiency and modularity of this synthetic strategy, it constitute a very attractive approach for generating structurally-diverse collections of benzofuran derivatives for small molecule screening.


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