248 research outputs found
The color of transformation: Investigations into heat treatment of Natufian artifacts from Hayonim Terrace (Israel)
In the Natufian lithic component at Hayonim, both in the cave and the terrace, numerous artifacts of pink/red color may be recognized. Cherts with similar appearance are not present in the geological environment surrounding the site in Northern Israel. Pink chert available in Jordan is shown to be of different nature. Thus this leaves us with the hypothesis of intentional heat treatment of locally available iron-rich yellow chert, of Cenomanian age. Based on experimental replication of chert firing and SEM analysis, we argue that a well-mastered and controlled use of fire was practiced by some skilled craftsmen at Hayonim throughtout the Late Epipalaeolithic
Anodic Alumina Membranes: From Electrochemical Growth to Use as Template for Fabrication of Nanostructured Electrodes
The great success of anodic alumina membranes is due to their morphological features coupled to both thermal and chemical stability. The electrochemical fabrication allows accurate control of the porous structure: in fact, the membrane morphological characteristics (pore length, pore diameter and cell density) can be controlled by adjusting the anodizing parameters (bath, temperature, voltage and time). This article deals with both the fabrication and use of anodic alumina membranes. In particular, we will show the specific role of the addition of aluminum ions to phosphoric acid-based anodizing solution in modifying the morphology of anodic alumina membranes. Anodic alumina membranes were obtained at −1◦ C in aqueous solutions of 0.4 M H3 PO4 added with different amounts of Al(OH)3 . For sake of completeness, the formation of PAA in pure 0.4 M H3 PO4 in otherwise identical conditions was also investigated. We found that the presence of Al(OH)3 in solution highly affects the morphology of the porous layer. In particular, at high Al(OH)3 concentration (close to saturation) more compact porous layers were formed with narrow pores separated by thick oxide. The increase in the electric charge from 20 to 160 C cm−2 also contributes to modifying the morphology of porous oxide. The obtained anodic alumina membranes were used as a template to fabricate a regular array of PdCo alloy nanowires that is a valid alternative to Pt for hydrogen evolution reaction. The PdCo alloy was obtained by electrodeposition and we found that the composition of the nanowires depends on the concentration of two metals in the deposition solution
SNP genotyping elucidates the genetic diversity of Magna Graecia grapevine germplasm and its historical origin and dissemination
Background: Magna Graecia is the ancient name for the modern geopolitical region of South Italy extensively populated by Greek colonizers, shown by archeological and historical evidence to be the oldest wine growing region of Italy, crucial for the spread of specialized viticulture around Mediterranean shores. Here, the genetic diversity of Magna Graecia grape germplasm was assessed and its role in grapevine propagation around the Mediterranean basin was underlined. Results: A large collection of grapevines from Magna Graecia was compared with germplasm from Georgia to the Iberian Peninsula using the 18 K SNP array. A high level of genetic diversity of the analyzed germplasm was determined; clustering, structure analysis and DAPC (Discriminant Analysis of Principal Components) highlighted the genetic relationships among genotypes from South Italy and the Eastern Mediterranean (Greece). Gene flow from east (Georgia) to west (Iberian Peninsula) was identified throughout the large number of detected admixed samples. Pedigree analysis showed a complex and well-structured network of first degree relationships, where the cultivars from Magna Graecia were mainly involved. Conclusions: This study provided evidence that Magna Graecia germplasm was shaped by historical events that occurred in the area due to the robust link between South Italian and Greek genotypes, as well as, by the availability of different thermal resources for cultivars growing in such different winegrowing areas. The uniqueness of this ampelographic platform was mainly an outcome of complex natural or human-driven crosses involving elite cultivars
SNP genotyping elucidates the genetic diversity of Magna Graecia grapevine germplasm and its historical origin and dissemination
BACKGROUND:
Magna Graecia is the ancient name for the modern geopolitical region of South Italy extensively populated by Greek colonizers, shown by archeological and historical evidence to be the oldest wine growing region of Italy, crucial for the spread of specialized viticulture around Mediterranean shores. Here, the genetic diversity of Magna Graecia grape germplasm was assessed and its role in grapevine propagation around the Mediterranean basin was underlined.
RESULTS:
A large collection of grapevines from Magna Graecia was compared with germplasm from Georgia to the Iberian Peninsula using the 18\u2009K SNP array. A high level of genetic diversity of the analyzed germplasm was determined; clustering, structure analysis and DAPC (Discriminant Analysis of Principal Components) highlighted the genetic relationships among genotypes from South Italy and the Eastern Mediterranean (Greece). Gene flow from east (Georgia) to west (Iberian Peninsula) was identified throughout the large number of detected admixed samples. Pedigree analysis showed a complex and well-structured network of first degree relationships, where the cultivars from Magna Graecia were mainly involved.
CONCLUSIONS:
This study provided evidence that Magna Graecia germplasm was shaped by historical events that occurred in the area due to the robust link between South Italian and Greek genotypes, as well as, by the availability of different thermal resources for cultivars growing in such different winegrowing areas. The uniqueness of this ampelographic platform was mainly an outcome of complex natural or human-driven crosses involving elite cultivars
Photometric and spectroscopic analysis of the Type II SN 2020jfo with a short plateau
We present high-cadence photometric and spectroscopic observations of
SN~2020jfo in ultraviolet and optical/near-infrared bands starting from to days after the explosion, including the earliest data with the
10.4\,m GTC. SN~2020jfo is a hydrogen-rich Type II SN with a relatively short
plateau duration ( days). When compared to other Type II
supernovae (SNe) of similar or shorter plateau lengths, SN~2020jfo exhibits a
fainter peak absolute -band magnitude ( mag).
SN~2020jfo shows significant H absorption in the plateau phase similar
to that of typical SNe~II. The emission line of stable [Ni~II] 7378,
mostly seen in low-luminosity SNe~II, is very prominent in the nebular-phase
spectra of SN~2020jfo. Using the relative strengths of [Ni~II] 7378
and [Fe~II] 7155, we derive the Ni/Fe production (abundance) ratio of
0.08--0.10, which is times the solar value. The progenitor mass of
SN~2020jfo from nebular-phase spectral modelling and semi-analytical modelling
falls in the range of 12--15\,. Furthermore, semi-analytical modelling
suggests a massive H envelope in the progenitor of SN~2020jfo, which is
unlikely for SNe~II having short plateaus.Comment: 20 pages (plus 5 pages appendix), 19 figures, Accepted for
publication in MNRA
Securing the Downside Up: Client and Care Factors Associated with Outcomes of Secure Residential Youth Care
Although secure residential care has the potential of reducing young people's behavioral problems, it is often difficult to achieve positive outcomes. Research suggests that there are several common success factors of treatment, of which the client's motivation for treatment and the quality of the therapeutic relationship between clients and therapists might be especially relevant and important in the context of secure residential care. The objective of the present study was to explore the association of these potential success factors with secure residential care outcomes. A repeated measures research design was applied in the study, including a group of adolescents in a secure residential care center that was followed up on three measurements in time. Interviews and questionnaires concerning care outcomes in terms of adolescents' behavior change during care were administered to 22 adolescents and 27 group care workers. Outcomes in terms of adolescents' treatment satisfaction were assessed by the use of questionnaires, which were completed by 51 adolescents. Adolescents reported some positive changes in their treatment motivation, but those who were more likely to be motivated at admission were also more likely to deteriorate in treatment motivation from admission to departure. Treatment satisfaction was associated with better treatment motivation at admission and with a positive adolescent-group care worker relationship. The results suggest that outcomes can be improved by a more explicit treatment focus on improving the adolescent's treatment motivation and the quality of the adolescent-care worker relationship during secure residential care
The asparagus genome sheds light on the origin and evolution of a young Y chromosome
Several models have been proposed to explain the emergence of sex chromosomes. Here, through comparative genomics and mutant analysis, Harkess et al. show that linked but separate genes on the Y chromosome are responsible for sex determination in Asparagus, supporting a two-gene model for sex chromosome evolution
Crop wild relatives of the brinjal eggplant ( Solanum melongena ): Poorly represented in genebanks and many species at risk of extinction
This is the publisher's Early View pdf without final pagination .© 2016 Botanical Society of America. This is an open access article, available to all readers online, published under a creative commons license. The attached file is the published version of the article
- …