468 research outputs found
Minimal knotted polygons in cubic lattices
An implementation of BFACF-style algorithms on knotted polygons in the simple
cubic, face centered cubic and body centered cubic lattice is used to estimate
the statistics and writhe of minimal length knotted polygons in each of the
lattices. Data are collected and analysed on minimal length knotted polygons,
their entropy, and their lattice curvature and writhe
Social democracy, embeddedness and decommodification: On the conceptual innovations and intellectual affiliations of Karl Polanyi
Of the several debates that revolve around the work of the economic historian and political economist Karl Polanyi, one that continues to exercise minds concerns his analysis of, and political attitudes toward, post-war capitalism and the welfare state. Simplified a little, it is a debate with two sides. To borrow Iván Szelényi's terms, one side constructs a ‘hard’ Karl Polanyi, the other a ‘soft’ one. The former advocated a socialist mixed economy dominated by redistributive mechanisms. He was a radical socialist for whom the market should never be the dominant mechanism of economic coordination. His ‘soft’ alter ego insisted that the market system remain essentially intact but be complemented by redistributive mechanisms. The ‘double movement’ – the central thesis of his ‘Great Transformation’ – acts, in this reading, as a self-correcting mechanism that moderates the excesses of market fundamentalism; its author was positioned within the social-democratic mainstream for which the only realistic desirable goal is a regulated form of capitalism. In terms of textual evidence there is much to be said for both interpretations. In this article I suggest a different approach, one that focuses upon the meaning of Polanyi's concepts in relation to their socio-political and intellectual environment
European consensus meeting of ARM-Net members concerning diagnosis and early management of newborns with anorectal malformations.
The ARM-Net (anorectal malformation network) consortium held a consensus meeting in which the classification of ARM and preoperative workup were evaluated with the aim of improving monitoring of treatment and outcome. The Krickenbeck classification of ARM and preoperative workup suggested by Levitt and Peña, used as a template, were discussed, and a collaborative consensus was achieved. The Krickenbeck classification is appropriate in describing ARM for clinical use. The preoperative workup was slightly modified. In males with a visible fistula, no cross-table lateral X-ray is needed and an anoplasty or (mini-) posterior sagittal anorectoplasty can directly be performed. In females with a small vestibular fistula (Hegar size 5 mm, and in the meantime, gentle painless dilatations can be performed. In both male and female perineal fistula and either a low birth weight (<2,000 g) or severe associated congenital anomalies, prolonged preoperative painless dilatations might be indicated to decrease perioperative morbidity caused by general anesthesia. The Krickenbeck classification is appropriate in describing ARM for clinical use. Some minor modifications to the preoperative workup by Levitt and Peña have been introduced in order to refine terminology and establish a comprehensive preoperative workup
Copy number variations in 375 patients with oesophageal atresia and/or tracheoesophageal fistula
Oesophageal atresia (OA) with or without tracheoesophageal fistula (TOF) are rare anatomical congenital malformations whose cause is unknown in over 90% of patients. A genetic background is suggested, and among the reported genetic defects are copy number variations (CNVs). We hypothesized that CNVs contribute to OA/TOF development. Quantifying their prevalence could aid in genetic diagnosis and clinical care strategies. Therefore, we profiled 375 patients in a combined Dutch, American and German cohort via genomic microarray and compared the CNV profiles with their unaffected parents and published control cohorts. We identified 167 rare CNVs containing genes (frequency<0.0005 in our in-house cohort). Eight rare CNVs - in six patients - were de novo, including one CNV previously associated with oesophageal disease. (hg19 chr7:g.(143820444-143839360)-(159119486-159138663)del) 1.55% of isolated OA/TOF patients and 1.62% of patients with additional congenital anomalies had de novo CNVs. Furthermore, three (15q13.3, 16p13.3 and 22q11.2) susceptibility loci were identified based on their overlap with known OA/TOF-associated CNV syndromes and overlap with loci in published CNV association case-control studies in developmental delay. Our study suggests that CNVs contribute to OA/TOF development. In addition to the identified likely deleterious de novo CNVs, we detected 167 rare CNVs. Although not directly disease-causing, these CNVs might be of interest, as they can act as a modifier in a multiple hit model, or as the second hit in a recessive condition
Comment on Spracklandus Hoser, 2009 (Reptilia, Serpentes, ELAPIDAE): request for confirmation of the availability of the generic name and for the nomenclatural validation of the journal in which it was published (Case 3601; see BZN 70: 234–237; 71: 30–38, 133–135, 181–182, 252–253)
Deafening silence? Marxism, international historical sociology and the spectre of Eurocentrism
Approaching the centenary of its establishment as a formal discipline, International Relations today challenges the ahistorical and aspatial frameworks advanced by the theories of earlier luminaries. Yet, despite a burgeoning body of literature built on the transdisciplinary efforts bridging International Relations and its long-separated nomothetic relatives, the new and emerging conceptual frameworks have not been able to effectively overcome the challenge posed by the ‘non-West’. The recent wave of international historical sociology has highlighted possible trajectories to problematise the myopic and unipolar conceptions of the international system; however, the question of Eurocentrism still lingers in the developing research programmes. This article interjects into the ongoing historical materialist debate in international historical sociology by: (1) conceptually and empirically challenging the rigid boundaries of the extant approaches; and (2) critically assessing the postulations of recent theorising on ‘the international’, capitalist states-system/geopolitics and uneven and combined development. While the significance of the present contributions in international historical sociology should not be understated, it is argued that the ‘Eurocentric cage’ still occupies a dominant ontological position which essentially silences ‘connected histories’ and conceals the role of inter-societal relations in the making of the modern states-system and capitalist geopolitics
Uneven and combined development and unequal exchange: the second wind of neoliberal ‘free trade’?
With capitalist social relations emerging in a prior system of absolutist states in Europe, the outward expansion of capitalism through conditions of uneven and combined development became dependent on the existence of multiple political entities. States in turn are brought into relations of unequal exchange within the global economy. This article analyses the way in which current neoliberal ‘free trade’ policies are related to these fundamental capitalist dynamics, deepening further processes of uneven and combined development as well as unequal exchange
Sources and nature of ice-nucleating particles in the free troposphere at Jungfraujoch in winter 2017
Primary ice formation in mixed-phase clouds is initiated by a
minute subset of the ambient aerosol population, called ice-nucleating
particles (INPs). The knowledge about their atmospheric concentration,
composition, and source in cloud-relevant environments is still limited.
During the 2017 joint INUIT/CLACE (Ice Nuclei research UnIT/CLoud–Aerosol
Characterization Experiment) field campaign, observations of INPs as
well as of aerosol physical and chemical properties were performed,
complemented by source region modeling. This aimed at investigating the
nature and sources of INPs. The campaign took place at the High-Altitude
Research Station Jungfraujoch (JFJ), a location where mixed-phase clouds
frequently occur. Due to its altitude of 3580 m a.s.l., the station is
usually located in the lower free troposphere, but it can also receive air
masses from terrestrial and marine sources via long-range transport. INP
concentrations were quasi-continuously detected with the Horizontal Ice
Nucleation Chamber (HINC) under conditions representing the formation of
mixed-phase clouds at −31 ∘C. The INP measurements were performed
in parallel to aerosol measurements from two single-particle mass
spectrometers, the Aircraft-based Laser ABlation Aerosol MAss Spectrometer
(ALABAMA) and the laser ablation aerosol particle time-of-flight mass
spectrometer (LAAPTOF). The chemical identity of INPs is inferred by
correlating the time series of ion signals measured by the mass
spectrometers with the time series of INP measurements. Moreover, our
results are complemented by the direct analysis of ice particle residuals
(IPRs) by using an ice-selective inlet (Ice-CVI) coupled with the ALABAMA.
Mineral dust particles and aged sea spray particles showed the highest
correlations with the INP time series. Their role as INPs is further
supported by source emission sensitivity analysis using atmospheric
transport modeling, which confirmed that air masses were advected from the
Sahara and marine environments during times of elevated INP
concentrations and ice-active surface site densities. Indeed, the IPR
analysis showed that, by number, mineral dust particles dominated the IPR
composition (∼58 %), and biological and metallic
particles are also found to a smaller extent (∼10 % each). Sea
spray particles are also found as IPRs (17 %), and their fraction in the
IPRs strongly varied according to the increased presence of small IPRs,
which is likely due to an impact from secondary ice crystal formation. This
study shows the capability of combining INP concentration measurements with
chemical characterization of aerosol particles using single-particle mass
spectrometry, source region modeling, and analysis of ice residuals in an
environment directly relevant for mixed-phase cloud formation.</p
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