5,431 research outputs found
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Fluvial stratigraphy and palaeoenvironments in the Pasinler Basin, eastern Turkey
Valley floor sediments from the Pasinler Basin, eastern Turkey, provide evidence for Pleistocene and Holocene floodplain conditions. Three terrace surfaces are present. Evidence for tectonic processes active during the Late Neogene are widespread within the basin but do not appear to have substantially influenced the detail of the Holocene palaeoenvironmental record. Significant changes in hydrology are recorded, with more stable floodplain conditions occurring at around 9,000, 5,500 and 4,000 cal. yr. BP. Incision occurred sometime after approximately 4,000 BP, probably as a response to dual climatic and human controls. Comparisons with key sites in the Anatolian region and beyond suggest these changes are part of a regional climatic pattern, perhaps influenced by changes in the East African Monsoon. Differences in the details of the records across the region reflect the characteristics of the local environment, which, increasingly in the latter Holocene, includes human activity
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Rescoring the NIH chronic prostatitis symptom index: nothing new.
The National Institutes of Health-chronic prostatitis symptom index (NIH-CPSI) is a commonly used 13-item questionnaire for the assessment of symptom severity in men with chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS). For each item, score ranges are 0-1 (6 items), 0-3 (2 items), 0-5 (3 items), 0-6 (1 item) and 0-10 (1 item). This scoring system is straightforward, but items with wider score ranges are de facto weighted more, which could adversely affect the performance characteristics of the questionnaire. We rescored the NIH-CPSI so that equal weights were assigned to each item, and compared the performance of the standard and rescored questionnaires using the original validation dataset. Both the original and revised versions of the scoring algorithm discriminated similarly among groups of men with CP (n=151), benign prostatic hyperplasia (n=149) and controls (n=134). The internal consistency of the questionnaire was slightly better with the revised scoring, but values with the standard scoring were sufficiently high (Cronbach's >or=0.80). We conclude that although the rescored NIH-CPSI provides better face validity than the standard scoring algorithm, it requires additional calculation efforts and yields only marginal improvements in performance
Geomorphological insight into changing tectonic regime, Pasinler Basin, Turkey
The Pasinler Basin, in the East Anatolian Contractional Province, features a suite of
geomorphological zones, visible in the field, air photographs and Landsat and SRTM
DEM imagery. These zones reflect past and current tectonically influenced processes.
Collins et al: Geomorphological insight into changing tectonic regime, Pasinler Basin, Turkey. 2 of 26
Remnants of the Erzurum-Kars plateau representing Mio-Pliocene volcanism,
associated with transtensional tectonics, have been modified by two stages of drainage
development: an earlier, shallow valley network, which was modified following uplift and
tilting to form the present system characterised by deep narrow valleys that supply
alluvial fan complexes. These fans discharge onto the present, aggradation-dominated
basin floor. Initial normal faulting induced massive slope failures on the basin’s northern
margin. This extensional phase within the basin was reversed by the Late Pleistocene,
with thrust faults modifying and producing landforms, and affecting sediment sequences,
along both the north and south basin margins. The shift from a transtensional regime
and associated volcanism to normal faulting in the Pliocene-Early Pleistocene, and then
to the present compression-dominated regime appears to correspond with regional
tectonic changes resulting from collision of the Arabian microplate and the subsequent
westward movement of the Anatolian microplate
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Primary care physician practices in the diagnosis, treatment and management of men with chronic prostatitis/chronic pelvic pain syndrome.
To describe practice patterns of primary care physicians (PCPs) for the diagnosis, treatment and management of chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS), we surveyed 556 PCPs in Boston, Chicago, and Los Angeles (RR=52%). Only 62% reported ever seeing a patient like the one described in the vignette. In all, 16% were 'not at all' familiar with CP/CPPS, and 48% were 'not at all' familiar with the National Institutes of Health classification scheme. PCPs reported practice patterns regarding CP/CPPS, which are not supported by evidence. Although studies suggest that CP/CPPS is common, many PCPs reported little or no familiarity, important knowledge deficits and limited experience in managing men with this syndrome
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Idealized Carbon-Based Materials Exhibiting Record Deliverable Capacities for Vehicular Methane Storage
Materials
for vehicular methane storage have been extensively studied,
although no suitable material has been found. In this work, we use
molecular simulation to investigate three types of carbon-based materials,
Schwarzites, layered graphenes, and carbon nanoscrolls, for use in
vehicular methane storage under adsorption conditions of 65 bar and
298 K and desorption conditions of 5.8 bar and 358 K. Ten different
Schwarzites were tested and found to have high adsorption with maximums
at 273 VSTP/V, but middling deliverable capacities of no
more than 131 VSTP/V. Layered graphene and graphene nanoscrolls
were found to have extremely high CH4 adsorption capacities
of 355 and 339 VSTP/V, respectively, when the interlayer
distance was optimized to 11 Ã…. The deliverable capacities of
perfectly layered graphene and graphene nanoscrolls were also found
to be exceptional with values of 266 and 252 VSTP/V, respectively,
with optimized interlayer distances. These values make idealized graphene
and nanoscrolls the record holders for adsorption and deliverable
capacities under vehicular methane storage conditions
Colloquy
At present, our system of criminal law administration has a considerable Rube Goldberg quality to it. Once the system decides to imprison a particular defendant--if we except from the generalization the couple of states that recently changed their laws in fundamental respects--the judge naturally asks himself what will happen when this man goes to prison. The answer is that the convicted offender will sit in prison for as long as the parole board wants him to. The judge must next consider whether any constraints exist on the parole board\u27s decisions on when to release people from prison. In a third of the statutory sentences the judge can specify that the defendant must remain imprisoned for up to one third or one half of the time to which he is sentenced. The question then becomes how long the judge wants a particular defendant to stay in prison. He knows that a nine-year sentence will mean minimum parole eligibility after three years,and that the parole board releases prisoners on their first eligibility date in eighty-five percent of the cases. Therefore, judges purpose-fully inflate sentences to discount for their knowledge that the parole board decreases the sentences which a judge imposes
Out of the Shadows: A Young Woman\u27s Journey from Hiding to Celebrating her Identity
In April 2019 the UK government reported that little progress had been made to remedy social outcomes inequality between Roma and the wider population, recommending further recognition of Roma, for example in census data, to enable identification of Roma, their needs, and how to meet those needs. In this article we present an account of one Roma woman’s journey from hiding her identity to celebrating it. We expose five critical incidents that challenge and mould her sense of identity and career aspiration, with insights into her hopes and dreams as she reflects upon the barriers she faces and attempts to overcome. The narrative enhances understanding of the intersection of experience and ethnic identity formation, Marcella’s (pseudonym) case study emerges verbatim through quotes; we do not alter or correct her English. In our exploration, we follow the six classical steps recommended in case study analysis (Yin, 2009) and ground some of the key analytical concepts in Goffman’s theories of stigma (1963) and theatrical performances in everyday life. We conclude by identifying key parallels in her experience, relevant regardless of socioeconomic status to further debate on the nature of internalised shame, stigma, and class
Treatment of malignant tumors of the skull base with multi-session radiosurgery
<p>Abstract</p> <p>Objective</p> <p>Malignant tumors that involve the skull base pose significant challenges to the clinician because of the proximity of critical neurovascular structures and limited effectiveness of surgical resection without major morbidity. The purpose of this study was to evaluate the efficacy and safety of multi-session radiosurgery in patients with malignancies of the skull base.</p> <p>Methods</p> <p>Clinical and radiographic data for 37 patients treated with image-guided, multi-session radiosurgery between January 2002 and December 2007 were reviewed retrospectively. Lesions were classified according to involvement with the bones of the base of the skull and proximity to the cranial nerves.</p> <p>Results</p> <p>Our cohort consisted of 37 patients. Six patients with follow-up periods less than four weeks were eliminated from statistical consideration, thus leaving the data from 31 patients to be analyzed. The median follow-up was 37 weeks. Ten patients (32%) were alive at the end of the follow-up period. At last follow-up, or the time of death from systemic disease, tumor regression or stable local disease was observed in 23 lesions, representing an overall tumor control rate of 74%. For the remainder of lesions, the median time to progression was 24 weeks. The median progression-free survival was 230 weeks. The median overall survival was 39 weeks. In the absence of tumor progression, there were no cranial nerve, brainstem or vascular complications referable specifically to CyberKnife<sup>® </sup>radiosurgery.</p> <p>Conclusion</p> <p>Our experience suggests that multi-session radiosurgery for the treatment of malignant skull base tumors is comparable to other radiosurgical techniques in progression-free survival, local tumor control, and adverse effects.</p
Signal Propagation in Feedforward Neuronal Networks with Unreliable Synapses
In this paper, we systematically investigate both the synfire propagation and
firing rate propagation in feedforward neuronal network coupled in an
all-to-all fashion. In contrast to most earlier work, where only reliable
synaptic connections are considered, we mainly examine the effects of
unreliable synapses on both types of neural activity propagation in this work.
We first study networks composed of purely excitatory neurons. Our results show
that both the successful transmission probability and excitatory synaptic
strength largely influence the propagation of these two types of neural
activities, and better tuning of these synaptic parameters makes the considered
network support stable signal propagation. It is also found that noise has
significant but different impacts on these two types of propagation. The
additive Gaussian white noise has the tendency to reduce the precision of the
synfire activity, whereas noise with appropriate intensity can enhance the
performance of firing rate propagation. Further simulations indicate that the
propagation dynamics of the considered neuronal network is not simply
determined by the average amount of received neurotransmitter for each neuron
in a time instant, but also largely influenced by the stochastic effect of
neurotransmitter release. Second, we compare our results with those obtained in
corresponding feedforward neuronal networks connected with reliable synapses
but in a random coupling fashion. We confirm that some differences can be
observed in these two different feedforward neuronal network models. Finally,
we study the signal propagation in feedforward neuronal networks consisting of
both excitatory and inhibitory neurons, and demonstrate that inhibition also
plays an important role in signal propagation in the considered networks.Comment: 33pages, 16 figures; Journal of Computational Neuroscience
(published
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