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The study of marriage seasonality of populations with different socioeconomic backgrounds may contribute to the better understanding their reproductive behaviours. This study analyses the monthly distribution of marriages in the 19th century in four agricultural villages and four pastoral villages on the island of Sardinia (Italy). The data were derived from 7340 marriage acts (3571 for the four agricultural villages and 3769 for the four pastoral villages). The aim is to ascertain whether the Sardinian agricultural and pastoral communities followed the matrimonial models reported for contemporary Italy and Europe and whether there was a change in the monthly distribution of marriages between the two halves of the 19th century. The results suggest that the marriage seasonality of the Sardinian farmers and shepherds was very similar to the patterns shown in the 19th century by Italian and European agricultural and pastoral communities. The Sardinian farmers preferred to marry in autumn-winter, while the Sardinian shepherds had a very high concentration of marriages in summer-autumn. Both communities avoided marriages in the Advent and Easter periods and in the month of May (dedicated to the Virgin Mary), and the farmers also in August (also dedicated to the Virgin Mary). Despite a certain seasonal stability, there was a significant change in the monthly distribution of marriages between the two halves of the 19th century in both the agricultural and pastoral communities, probably due to a series of laws that transformed the centuries-old socioeconomic system of Sardinia in the second half of the century. 相似文献
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An amidic derivative of a carboxymethylcellulose-based hydrogel was obtained and characterized in terms of amidation degree. NMR studies and FT-IR imaging spectroscopy demonstrated that the reaction allowed a polymer to be obtained that was characterized by a regular distribution of amidic groups along the polysaccharide chains. Through this regularity, a homogenous three-dimensional scaffold was obtained, which maintained the thixotropic property of the linear polysaccharide. 相似文献
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Organization and Regulation of meta Cleavage Pathway Genes for Toluene and o-Xylene Derivative Degradation in Pseudomonas stutzeri OX1 下载免费PDF全文
Fabio L. G. Arenghi Davide Berlanda Enrica Galli Guido Sello Paola Barbieri 《Applied microbiology》2001,67(7):3304-3308
Pseudomonas stutzeri OX1 meta pathway genes for toluene and o-xylene catabolism were analyzed, and loci encoding phenol hydroxylase, catechol 2,3-dioxygenase, 2-hydroxymuconate semialdehyde dehydrogenase, and 2-hydroxymuconate semialdehyde hydrolase were mapped. Phenol hydroxylase converted a broad range of substrates, as it was also able to transform the nongrowth substrates 2,4-dimethylphenol and 2,5-dimethylphenol into 3,5-dimethylcatechol and 3,6-dimethylcatechol, respectively, which, however, were not cleaved by catechol 2,3-dioxygenase. The identified gene cluster displayed a gene order similar to that of the Pseudomonas sp. strain CF600 dmp operon for phenol catabolism and was found to be coregulated by the tou operon activator TouR. A hypothesis about the evolution of the toluene and o-xylene catabolic pathway in P. stutzeri OX1 is discussed. 相似文献
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Enrica L. Santarcangelo Giulia Paoletti Iacopo Chiavacci Carlo Palombo Giancarlo Carli Maurizio Varanini 《PloS one》2013,8(10)
In healthy subjects with high hypnotisability (highs) under hypnosis, subjectively effective suggestions for analgesia abolish the increases in blood pressure associated with cold pressor test (cpt) by reducing the peripheral vascular resistance. The aim of the present study was to investigate the effects of the suggestions of analgesia on the responses to cpt in healthy highs (n = 22) and in low hypnotisable participants (lows, n = 22) out of hypnosis. Cpt was administered without (CPT) and with suggestions for analgesia (CPT+AN). Psychophysical (pain intensity, pain threshold, cpt duration (time of immersion) and pain tolerance, defined as the difference between cpt duration and pain threshold), respiratory (amplitude and frequency) and autonomic variables (tonic skin conductance, mean RR interval (RR = 1/heart rate), blood pressure, skin blood flow) were studied. The suggestions for analgesia increased cpt duration and RR in both groups, but decreased pain intensity and enhanced pain threshold only in highs; in both groups they did not modulate systolic blood pressure, tonic skin conductance and skin blood flow; thus, increased parasympathetic activity appears responsible for the heart rate reduction induced by suggestions in both groups. In conclusion, our findings show that suggestions modulate pain experience differentially in highs and lows, and are partially effective also in lows. We hypothesize that the mechanisms responsible for the efficacy of suggestions in healthy lows may be involved also in their efficacy in chronic pain patients with low hypnotisability. 相似文献
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Fabrizio Briganti Demetrio Randazzo Andrea Scozzafava Debora Berti Piero Baglioni Patrizia Di Gennaro Enrica Galli Giuseppina Bestetti 《Journal of Molecular Catalysis .B, Enzymatic》1999,7(5-6):263-272
The whole cell biological conversion of naphthalene to (+)-cis-(1R,2S)-dihydroxy-1,2-dihydronaphthalene by the E. coli JM109(pPS1778) recombinant strain carrying the naphthalene dioxygenase and regulatory genes cloned from Pseudomonas fluorescens N3 in micellar systems has been investigated using biochemical and chemico-physical techniques. Reverse and direct micellar systems have been tested. Non-ionic surfactants (Tween and Triton X series) were found not to inhibit either the growth of the bacteria and the expression of the hydroxylating dioxygenase enzyme in such systems and were utilized in order to speed up the naphthalene conversion by increasing its solubility and also its bioavailability. The phase behavior of the direct micellar system was characterized through light scattering and other chemico-physical techniques. Further addition of isopropyl-palmitate 1–2% v/v to the micellar systems resulted in an increase of the apparent substrate concentration in solution and particularly its bioavailability thus allowing faster catalytic conversions resulting in an increase in productivity for the process. Since the cis-dihydrodiols are acquiring considerable potential as chiral pool synthons in asymmetric synthesis for a variety of industrial processes, possible applications for efficient small and large-scale production of such compounds are discussed. 相似文献
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In vitro evidence for the participation of Drosophila melanogaster sperm β‐N‐acetylglucosaminidases in the interactions with glycans carrying terminal N‐acetylglucosamine residues on the egg's envelopes 下载免费PDF全文
Jari Intra Concetta Veltri Daniela De Caro Maria Elisa Perotti Maria Enrica Pasini 《Archives of insect biochemistry and physiology》2017,96(1)
Fertilization is a complex and multiphasic process, consisting of several steps, where egg‐coating envelope's glycoproteins and sperm surface receptors play a critical role. Sperm‐associated β‐N‐acetylglucosaminidases, also known as hexosaminidases, have been identified in a variety of organisms. Previously, two isoforms of hexosaminidases, named here DmHEXA and DmHEXB, were found as intrinsic proteins in the sperm plasma membrane of Drosophila melanogaster. In the present work, we carried out different approaches using solid‐phase assays in order to analyze the oligosaccharide recognition ability of D. melanogaster sperm hexosaminidases to interact with well‐defined carbohydrate chains that might functionally mimic egg glycoconjugates. Our results showed that Drosophila hexosaminidases prefer glycans carrying terminal β‐N‐acetylglucosamine, but not core β‐N‐acetylglucosamine residues. The capacity of sperm β‐N‐acetylhexosaminidases to bind micropylar chorion and vitelline envelope was examined in vitro assays. Binding was completely blocked when β‐N‐acetylhexosaminidases were preincubated with the glycoproteins ovalbumin and transferrin, and the monosaccharide β‐N‐acetylglucosamine. Overall, these data support the hypothesis of the potential role of these glycosidases in sperm–egg interactions in Drosophila. 相似文献