Search results for " function"
showing 10 items of 9395 documents
Arrendaments i parceries. La gestió indirecta de la terra al País Valencià (segles XIV-XV)
2002
In this article, it is studied the market of land lease in the Valentian rural society in the end of the Middle Age. Using notarial sources and court rolls, it is possible to know the economic function that exercised this forms of land management in the agrarian system. The penetration of urban capital through this kind of contracts was always limited. Far from eroding the hegemony of the small peasant farming, leases consolidated this pattern as productive basis of the feudal system.<br><br>En aquest article s'estudia el mercat de cessió de la terra a curt termini en la societat rural valenciana a les darreries de l’Edat Mitjana. A partir de fonts notarials i judicials, es pot …
Climate and agriculture: empirical evidence for countries and agroecological zones of the Sahel
2022
International audience; ow heterogenous is the impact of climate change across space and the type of agricultural production? In this paper, we investigate the relationship between climate change and variability, measured by temperature and rainfall, and agricultural production at the country and agroecological zone levels of the Sahel. We consider a crop production index and five cereals (maize, millet, sorghum, wheat and rice). Based on an original climate database and an agricultural production function estimated for the period 1961–2016, we show that average rainfall and temperature during the growing season indeed have highly heterogeneous effects on agricultural production, depending …
A socio-ecological perspective on alcohol use in adolescence
2012
Alcohol use among adolescents has become a public health problem(Morawska & Oei,2005). Although the frequency and the amount of alcoholic beverages consumed vary greatly from different countries and cultures, in two thirds of the ESPAD countries the vast majority of the students (15-16 years) have drank alcohol at least once in their lifetime. Moreover, in half of the participating countries, 47% of the students had consumed at least one glass of alcohol at the age of 13 or younger, and 14% had been drunk at that age. These changing patterns of consumption are associated with a variety of negative outcomes (Coleman & Cater, 2003). In a socio-ecological perspective, many studies (Nation & He…
Fixed point theorems for twisted (α,β)-ψ-contractive type mappings and applications
2013
The purpose of this paper is to discuss the existence and uniqueness of fixed points for new classes of mappings defined on a complete metric space. The obtained results generalize some recent theorems in the literature. Several applications and interesting consequences of our theorems are also given.
Distinctive amino acid residue periodicities in terminal sequences of type III and type I secreted proteins from proteobacteria
2007
AbstractThe Fourier transform (FT) method was applied to specify the distribution of 14 predefined groups of amino acids (64 residues) at both termini of annotated type III and type I secreted proteins from proteobacteria. Type I proteins displayed a higher occurrence of significant periodicities at both C-and N-termini, indicating potent features to discriminate between secretion types, particularly by the use of variables selected from the full periodicity profiles at 19 orders of FT. The Fishers linear discriminant analysis, together with the stepwise selection of variables throughout equal pairs of combinations for all predefined groups of residues, revealed the C-terminal harmonics of …
Oligomeric State and Holding Activity of Hsp60
2023
Similar to its bacterial homolog GroEL, Hsp60 in oligomeric conformation is known to work as a folding machine, with the assistance of co-chaperonin Hsp10 and ATP. However, recent results have evidenced that Hsp60 can stabilize aggregation-prone molecules in the absence of Hsp10 and ATP by a different, “holding-like” mechanism. Here, we investigated the relationship between the oligomeric conformation of Hsp60 and its ability to inhibit fibrillization of the Ab40 peptide. The monomeric or tetradecameric form of the protein was isolated, and its effect on beta-amyloid aggregation was separately tested. The structural stability of the two forms of Hsp60 was also investigated using differentia…
FATIGUE, SLEEP, AND NOCTURNAL COMPLAINTS IN PATIENTS WITH AMYOTROPHIC LATERAL SCLEROSIS.
2012
Background and purpose: Fatigue is a common symptom in amyotrophic lateral sclerosis (ALS). Although sleep disturbances are a candidate factor that may interfere with fatigue in patients with ALS, the role of sleep-related abnormalities in determining fatigue in ALS is unknown. Objective: To evaluate the frequency and determinants of fatigue in a group of 91 consecutive patients with ALS, with special attention to the relationship between fatigue and sleep problems. Methods: Measures included the Fatigue Severity Scale (FSS), Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), ALS Functional Rating Scale- Revised (ALSFRS-R), and Beck Depression Inventory (BDI). Results: T…
High frequency rTMS over the left parietal lobule increases non-word reading accuracy
2012
Increasing evidence in the literature supports the usefulness of Transcranial Magnetic Stimulation (TMS) in studying reading processes. Two brain regions are primarily involved in phonological decoding: the left superior temporal gyrus (STG), which is associated with the auditory representation of spoken words, and the left inferior parietal lobe (IPL), which operates in phonological computation. This study aimed to clarify the specific contribution of IPL and STG to reading aloud and to evaluate the possibility of modulating healthy participants' task performance using high frequency repetitive TMS (hf-rTMS). The main finding is that hf-rTMS over the left IPL improves non-word reading accu…
Mutual inductance for an explicitly finite number of turns
2011
Published version of an article published in Progress In Electromagnetics Research B, 28, 273-287. Also available from the publisher at http://www.jpier.org/pierb/pier.php?paper=10110103 Non coaxial mutual inductance calculations, based on a Bessel function formulation, are presented for coils modelled by an explicitly finite number of circular turns. The mutual inductance of two such turns can be expressed as an integral of a product of three Bessel functions and an exponential factor, and it is shown that the exponential factors can be analytically summed as a simple geometric progression, or other related sums. This allows the mutual inductance of two thin solenoids to be expressed as an…
Unveiling the Unexpected Reactivity of Electrophilic Diazoalkanes in [3+2] Cycloaddition Reactions within Molecular Electron Density Theory
2021
The [3+2] cycloaddition (32CA) reactions of strongly nucleophilic norbornadiene (NBD), with simplest diazoalkane (DAA) and three DAAs of increased electrophilicity, have been studied within the Molecular Electron Density Theory (MEDT) at the MPWB1K/6-311G (d,p) computational level. These pmr-type 32CA reactions follow an asynchronous one-step mechanism with activation enthalpies ranging from 17.7 to 27.9 kcal·