1,333 research outputs found
Book Review: Trucking in the Age of Information
Trucking in the Age of Information (Dale Belman and Chelsea White, III, Editors) (Reviewed by Terence A. Brown, Pennsylvania State University at Harrisburg
Multiple domestications of asian rice
In their recent Correspondence about our study showingthat there were three origins of Asian rice2, Huang and Han suggest that the
methodology that we used to infer multiple domestications was flawed as it did not take account of the strong genetic bottleneck in japonica
A discriminatory test for the wheat B and G genomes reveals misclassified accessions of Triticum timopheevii and Triticum turgidum
The tetraploid wheat species Triticum turgidum and Triticum timopheevii are morphologically similar, and misidentification of material collected from the wild is possible. We compared published sequences for the Ppd-A1, Ppd-B1 and Ppd-G1 genes from multiple accessions of T. turgidum and T. timopheevii and devised a set of four polymerase chain reactions (PCRs), two specific for Ppd-B1 and two for Ppd-G1. We used these PCRs with 51 accessions of T. timopheevii and 20 of T. turgidum. Sixty of these accessions gave PCR products consistent with their taxon identifications, but the other eleven accessions gave anomalous results: ten accessions that were classified as T. turgidum were identified as T. timopheevii by the PCRs, and one T. timopheevii accession was typed as T. turgidum. We believe that these anomalies are not due to errors in the PCR tests because the results agree with a more comprehensive analysis of genome-wide single nucleotide polymorphisms, which similarly suggest that these eleven accessions have been misclassified. Our results therefore show that the accepted morphological tests for discrimination between T. turgidum and T. timopheevii might not be entirely robust, but that species identification can be made cheaply and quickly by PCRs directed at the Ppd-1 gene.info:eu-repo/semantics/publishedVersio
Kinship in Aegean Prehistory? Ancient DNA in Human Bones from Mainland Greece and Crete
Attempts were made to detect ancient DNA (aDNA) in samples of 89 human skeletons from Neolithic and Bronze Age sites in Greece and Crete. Ancient DNA was absent in specimens from Nea Nicomedia, Lerna, Kato Zakro: Karaviádena, and Mycenae Grave Circle A. For each of three skeletons sampled from Antron Grave Circle B, polymerase chain reactions (PCRs) gave products for nuclear but not mitochondrial DNA, but the yield of DNA was low and inconsistent, with replicate PCRs failing to give reproducible results. At Kouphovouno evidence for mitochondrial and/or nuclear aDNA was obtained from eight of the 20 skeletons that were examined, while at Mycenae Grave Circle B evidence for mitochondrial aDNA was obtained for four of the 22 skeletons that were studied, and in two cases confirmed the evidence of close kinship that had already been suggested by facial reconstruction: this in turn raises interesting questions of social relationships and the role of high-status women in MBA/LBA society. We conclude that, although aDNA might be present in some Eastern Mediterranean skeletons from later centuries of the Bronze Age, it is not commonly found in material from this period and is likely to be absent from older material.Στη μελέτη αυτή έγιναν προσπάθειες να αναγνωριστεί αρχαίο DNA (aDNA) σε δείγματα ογδόντα εννέα ανθρώπινων σκελετών προερχομένων από θέσεις της Νεολιθικής περιόδου και της Εποχής του Χαλκού στην Ελλάδα και την Κρήτη. Αρχαίο DNA δεν εντοπίστηκε σε δείγματα από τη Νέα Νικομήδεια, τη Λέρνα, την Κάτω Ζάκρο (Καραβιάδενα) και τον Ταφικό Κύκλο Α των Μυκηνών. Για κάθε έναν από τους τρεις σκελετούς, οι οποίοι εξετάστηκαν από τον Ταφικό Κύκλο Β της Αντρώνας, οι αλυσιδωτές αντιδράσεις πολυμεράσης (PCRs) απέφεραν αποτελέσματα για πυρηνικό αλλά όχι μιτοχονδριακό DNA. Η παραγωγή DNA ήταν χαμηλή και αντιφατική, με τα αντίγραφα πολυμεράσης να αποτυγχάνουν να αποφέρουν αναπαραγώγιμα αποτελέσματα. Στο Κουφόβουνο οκτώ από τους είκοσι σκελετούς, που εξετάστηκαν, έδωσαν στοιχεία για μιτοχονδρνακό ή/και πυρηνικό DNA, ενώ στον Ταφικό Κύκλο Β των Μυκηνών ενδείξεις για μιτοχονδριακό DNA έδωσαν τέσσερεις από τους είκοσι δύο σκελετούς, που μελετήθηκαν. Σε δύο περιπτώσεις επιβεβαιώθηκε η ένδειξη στενής συγγένειας, κάτι το οποίο είχε ήδη προταθεί με την αποκατάσταση των προσώπων: το γεγονός αυτό εγείρει ενδιαφέροντα ερωτήματα σχετικά με τις κοινωνικές σχέσεις και το ρόλο γυναικών υψηλής κοινωνικής στάθμης στην κοινωνία της Μέσης και της Ύστερης Εποχής του Χαλκού. Συμπεραίνουμε ότι, αν και μπορεί να αναγνωριστεί DNA σε ορισμένους σκελετούς της Ανατολικής Μεσογείου των τελευταίων αιώνων της Εποχής του Χαλκού, δεν εντοπίζεται συχνά σε υλικό αυτής της εποχής και ενδεχομένως απουσιάζει από παλαιότερο υλνκό.</jats:p
Multiregional origins of the domesticated tetraploid wheats
We used genotyping-by-sequencing (GBS) to investigate the evolutionary history of domesticated tetraploid wheats. With a panel of 189 wild and domesticated wheats, we identified 1,172,469 single nucleotide polymorphisms (SNPs) with a read depth ≥3. Principal component analyses (PCAs) separated the Triticum turgidum and Triticum timopheevii accessions, as well as wild T. turgidum from the domesticated emmers and the naked wheats, showing that SNP typing by GBS is capable of providing robust information on the genetic relationships between wheat species and subspecies. The PCAs and a neighbour-joining analysis suggested that domesticated tetraploid wheats have closest affinity with wild emmers from the northern Fertile Crescent, consistent with the results of previous genetic studies on the origins of domesticated wheat. However, a more detailed examination of admixture and allele sharing between domesticates and different wild populations, along with genome-wide association studies (GWAS), showed that the domesticated tetraploid wheats have also received a substantial genetic input from wild emmers from the southern Levant. Taking account of archaeological evidence that tetraploid wheats were first cultivated in the southern Levant, we suggest that a pre-domesticated crop spread from this region to southeast Turkey and became mixed with a wild emmer population from the northern Fertile Crescent. Fixation of the domestication traits in this mixed population would account for the allele sharing and GWAS results that we report. We also propose that feralization of the component of the pre-domesticated population that did not acquire domestication traits has resulted in the modern wild population from southeast Turkey displaying features of both the domesticates and wild emmer from the southern Levant, and hence appearing to be the sole progenitor of domesticated tetraploids when the phylogenetic relationships are studied by methods that assume a treelike pattern of evolution.This work was supported by: TAB, 339941, European Research Council; TAB, NE/M010805/1, Natural Environment Research Councilinfo:eu-repo/semantics/publishedVersio
Potential prognostic marker ubiquitin carboxyl-terminal hydrolase-L1 does not predict patient survival in non-small cell lung carcinoma
<p>Abstract</p> <p>Background</p> <p>Ubiquitin Carboxyl-Terminal Hydrolase-L1 (UCH-L1) is a deubiquitinating enzyme that is highly expressed throughout the central and peripheral nervous system and in cells of the diffuse neuroendocrine system. Aberrant function of UCH-L1 has been associated with neurological disorders such as Parkinson's disease and Alzheimer's disease. Moreover, UCH-L1 exhibits a variable expression pattern in cancer, acting either as a tumour suppressor or promoter, depending on the type of cancer. In non-small cell lung carcinoma primary tumour samples, UCH-L1 is highly expressed and is associated with an advanced tumour stage. This suggests UCH-L1 may be involved in oncogenic transformation and tumour invasion in NSCLC. However, the functional significance of UCH-L1 in the progression of NSCLC is unclear. The aim of this study was to investigate the role of UCH-L1 using NSCLC cell line models and to determine if it is clinically relevant as a prognostic marker for advanced stage disease.</p> <p>Methods</p> <p>UCH-L1 expression in NSCLC cell lines H838 and H157 was modulated by siRNA-knockdown, and the phenotypic changes were assessed by flow cytometry, haematoxylin & eosin (H&E) staining and poly (ADP-ribose) polymerase (PARP) cleavage. Metastatic potential was measured by the presence of phosphorylated myosin light chain (MLC2). Tumour microarrays were examined immunohistochemically for UCH-L1 expression. Kaplan-Meier curves were generated using UCH-L1 expression levels and patient survival data extracted from Gene Expression Omnibus data files.</p> <p>Results</p> <p>Expression of UCH-L1 was decreased by siRNA in both cell lines, resulting in increased cell death in H838 adenocarcinoma cells but not in the H157 squamous cell line. However, metastatic potential was reduced in H157 cells. Immunohistochemical staining of UCH-L1 in patient tumours confirmed it was preferentially expressed in squamous cell carcinoma rather than adenocarcinoma. However the Kaplan-Meier curves generated showed no correlation between UCH-L1 expression levels and patient outcome.</p> <p>Conclusions</p> <p>Although UCH-L1 appears to be involved in carcinogenic processes in NSCLC cell lines, the absence of correlation with patient survival indicates that caution is required in the use of UCH-L1 as a potential prognostic marker for advanced stage and metastasis in lung carcinoma.</p
Iron catalysed Negishi cross-coupling using simple ethyl-monophosphines
Reported is a rare example of the use of monophosphines in iron catalysed Negishi cross-coupling. Substrate scope in terms of alkyl bromide and diaryl zinc reagent is explored.</p
Climatic controls on the survival and loss of ancient types of barley on North Atlantic Islands
This study was partly funded by a Scottish Government Rural and Environment Science and Analytical Service award (PM, JW and TSG). The Scottish Northern Cairngorms reconstruction was finalised through the project NERC project ‘SCOT2K: Reconstructing 2000 years of Scottish climate from tree rings (NE/ K003097/1)’ while the new central and northwest Scottish data were developed as part of a NERC Iapetus PhD project.For ancient types of barley at sites in the Scottish Isles, Faroes, and Iceland, we calculated minimum temperature requirements for grain production (grain production threshold, GPT) as accumulated degree days over the cropping season. Site suitability for barley from AD 1200 to 2000 was investigated by comparing these thresholds with reconstructions of annual cropping season degree days (CSDD) using temperature and tree-ring data. In Iceland, between AD 1200 and 1500, reconstructed CSDD were more favorable in the southwest (Reykjavik), with fewer years below the GPT, than in the North, East and West, but there were two periods (1340–1389 and 1426–1475) with low average CSDD and several years below the GPT which possibly influenced the abandonment of barley cultivation around this time. Reconstructed CSDD for the Faroes (Tórshavn) had only one year below the GPT, but 15 periods of four or more consecutive years with low CSDD which would have challenged barley cultivation, especially in the thirteenth century. Reconstructed CSDD were highest for the Scottish Isles, allowing a more prominent role of barley in the farming system and economy. Nevertheless, years with poor harvests or famines were common and about half were associated with low CSDD, resulting in a significant temperature link but also demonstrating the important contribution of other factors. Despite frequent unfavorable years in both the Faroes and Scottish Isles, resilient production systems, well-adapted barley strains and socio-economic factors allowed barley cultivation to continue, and some ancient types to survive to the present day.Publisher PDFPeer reviewe
Safe and just operating spaces for regional social-ecological systems
Humanity faces a major global challenge in achieving wellbeing for all, while simultaneously ensuring that the biophysical processes and ecosystem services that underpin wellbeing are exploited within scientifically informed boundaries of sustainability. We propose a framework for defining the safe and just operating space for humanity that integrates social wellbeing into the original planetary boundaries concept (Rockström et al., 2009a,b) for application at regional scales. We argue that such a framework can: (1) increase the policy impact of the boundaries concept as most governance takes place at the regional rather than planetary scale; (2) contribute to the understanding and dissemination of complexity thinking throughout governance and policy-making; (3) act as a powerful metaphor and communication tool for regional equity and sustainability. We demonstrate the approach in two rural Chinese localities where we define the safe and just operating space that lies between an environmental ceiling and a social foundation from analysis of time series drawn from monitored and palaeoecological data, and from social survey statistics respectively. Agricultural intensification has led to poverty reduction, though not eradicated it, but at the expense of environmental degradation. Currently, the environmental ceiling is exceeded for degraded water quality at both localities even though the least well-met social standards are for available piped water and sanitation. The conjunction of these social needs and environmental constraints around the issue of water access and quality illustrates the broader value of the safe and just operating space approach for sustainable development
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