Altruism and voluntary provision of public goods

We study how people's predisposition towards altruism affects their behavior in a voluntary contributions public good experiment. We investigate whether a high level of contributions can be sustained in groups of subjects who have been pre-selected on the basis of their altruistic inclinations. In the first stage of the experiment, each subject responds to a psychology questionnaire that measures various dimensions of one''s personality. The subjects are then matched in groups according to their altruism scores, and engage in a voluntary contributions game. We consider whether the levels and dynamics of group contributions differ significantly between the groups with altruists and non-altruists. We find that subjects'' altruism has only a weak positive effect on group behavior in the public good game.Altruism

Reducing sensor complexity for monitoring wind turbine performance using principal component analysis

Availability and reliability are among the priority concerns for deployment of distributed generation (DG) systems, particularly when operating in a harsh environment. Condition monitoring (CM) can meet the requirement but has been challenged by large amounts of data needing to be processed in real time due to the large number of sensors being deployed. This paper proposes an optimal sensor selection method based on principal component analysis (PCA) for condition monitoring of a DG system oriented to wind turbines. The research was motivated by the fact that salient patterns in multivariable datasets can be extracted by PCA in order to identify monitoring parameters that contribute the most to the system variation. The proposed method is able to correlate the particular principal component to the corresponding monitoring variable, and hence facilitate the right sensor selection for the first time for the condition monitoring of wind turbines. The algorithms are examined with simulation data from PSCAD/EMTDC and SCADA data from an operational wind farm in the time, frequency, and instantaneous frequency domains. The results have shown that the proposed technique can reduce the number of monitoring variables whilst still maintaining sufficient information to detect the faults and hence assess the system’s conditions

Evolution of CDK1 Paralog Specializations in a Lineage With Fast Developing Planktonic Embryos

The active site of the essential CDK1 kinase is generated by core structural elements, among which the PSTAIRE motif in the critical αC-helix, is universally conserved in the single CDK1 ortholog of all metazoans. We report serial CDK1 duplications in the chordate, Oikopleura. Paralog diversifications in the PSTAIRE, activation loop substrate binding platform, ATP entrance site, hinge region, and main Cyclin binding interface, have undergone positive selection to subdivide ancestral CDK1 functions along the S-M phase cell cycle axis. Apparent coevolution of an exclusive CDK1d:Cyclin Ba/b pairing is required for oogenic meiosis and early embryogenesis, a period during which, unusually, CDK1d, rather than Cyclin Ba/b levels, oscillate, to drive very rapid cell cycles. Strikingly, the modified PSTAIRE of odCDK1d shows convergence over great evolutionary distance with plant CDKB, and in both cases, these variants exhibit increased specialization to M-phase.publishedVersio

An improved differential evolution algorithm and its applications to orbit design

Differential Evolution (DE) is a basic and robust evolutionary strategy that has been applied to determining the global optimum for complex optimization problems[1–5]. It was introduced in 1995 by Storn and Price [1] and has been successfully applied to optimization problems including nonlinear, non-differentiable, non-convex, and multi-model functions. DE algorithms show good convergence, high-reliability, simplicity, and a reduced number of controllable parameters [2]. Olds and Kluever [3] applied DE to an interplanetary trajectory optimization problem and demonstrated the effectiveness of DE to produce rapid solutions. Madavan [4] discussed various modifications to the DE algorithm, improved its computational efficiency, and applied it to aerodynamic shape optimization problems. DE algorithms are easy to use, as they require only a few robust control variables, which can be drawn from a well-defined numerical interval. However, the existing various DE algorithms also have limitations, being susceptible to instability and getting trapped into local optima[2]. Notable effort has been spent addressing this by coupling DE algorithms with other optimization algorithms (for example, Self Organizing Maps (SOM) [6], Dynamic Hill Climbing (DHC) [7], Neural Networks (NN) [7], Particle Swarm Optimization (PSO) [8]). In these cases, the additional algorithm is used as an additional loop within the optimization process, creating a hybrid system with an inner and outer loop. Such hybrid algorithms are inherently more complex and so the computation cost is increased. Attempting to address this, a self-adaptive DE was designed and applied to the orbit design problem for prioritized multiple targets by Chen[5]. However, the self-adaptive feature is somewhat limited as it relates only to the number of generations within the optimization. A Self-adaptive DE which can automatically adapt its learning strategies and the associated parameters during the evolving procedure was proposed by Qin and Suganthan[9] and 25 test functions were used to verify the algorithm

The Escherichia coli glucuronylsynthase promoted synthesis of steroid glucuronides: improved practicality and broader scope

A library of steroid glucuronides was prepared using the glucuronylsynthase derived from Escherichia coliβ-glucuronidase, followed by purification using solid-phase extraction. A representative range of steroid substrates were screened for synthesis on the milligram scale under optimised conditions with conversions dependent on steroid substitution and stereochemistry. Epiandrosterone (3β-hydroxy-5α-androstan-17-one) provided the highest conversion of 90% (84% isolated yield). The previously unreported glucuronide conjugates of methandriol (17α-methylandrost-5-ene-3β,17β-diol), cholest-5-ene-3β,25-diol and the designer steroid trenazone (17β-hydroxyestra-4,9-dien-3-one) were prepared on a multi-milligram scale suitable for characterisation by (1)H and (13)C NMR spectroscopy. The glucuronide conjugate of d5-etiocholanolone (2,2,3,4,4-d5-3α-hydroxy-5β-androstan-17-one), a target developed by the World Anti-Doping Agency as a certified reference material, was also prepared on a milligram scale. The improved E. coli glucuronylsynthase method provides for the rapid synthesis and purification of steroid glucuronides on a scale suitable for a range of analytical applications.Australian Research Council (DP110101235

Changing nationwide trends in endoscopic, medical and surgical admissions for inflammatory bowel disease: 2003-2013.

Background and study aims: In the last decade, there have been major advances in inflammatory bowel disease (IBD) management but their impact on hospital admissions requires evaluation. We aim to investigate nationwide trends in IBD surgical/medical elective and emergency admissions, including endoscopy and cytokine inhibitor infusions, between 2003 and 2013. Patients and methods: We used Hospital Episode Statistics and population data from the UK Office for National Statistics. Results: Age-sex standardised admission rates increased from 76.5 to 202.9/100 000 (p<0.001) and from 69.5 to 149.5/100 000 (p<0.001) for Crohn's disease (CD) and ulcerative colitis (UC) between 2003-2004 and 2012-2013, respectively. Mean length of stay (days) fell significantly for elective (from 2.6 to 0.7 and from 2.0 to 0.7 for CD and UC, respectively) and emergency admissions (from 9.2 to 6.8 and from 10.8 to 7.6 for CD and UC, respectively). Elective lower gastrointestinal (GI) endoscopy rates decreased from 6.3% to 3.7% (p<0.001) and from 18.4% to 17.6% (p=0.002) for CD and UC, respectively. Elective major abdominal surgery rates decreased from 2.8% to 1.0% (p<0.001) and from 4.9 to 2.4 (p=0.010) for CD and UC, respectively, with emergency rates also decreasing significantly for CD. Between 2006-2007 and 2012-2013, elective admission rates for cytokine-inhibitor infusions increased from 11.1 to 57.2/100 000 and from 1.4 to 12.1/100 000 for CD and UC, respectively. Conclusions: Rising IBD hospital admission rates in the past decade have been driven by an increase in the incidence and prevalence of IBD. Lower GI endoscopy and surgery rates have fallen, while cytokine inhibitor infusion rates have risen. There has been a concurrent shift from emergency care to shorter elective hospital stays. These trends indicate a move towards more elective medical management and may reflect improvements in disease control

A Family of GFP-like Proteins with Different Spectral Properties in Lancelet Branchiostoma Floridae

Background: Members of the green fluorescent protein (GFP) family share sequence similarity and the 11-stranded β-barrel fold. Fluorescence or bright coloration, observed in many members of this family, is enabled by the intrinsic properties of the polypeptide chain itself, without the requirement for cofactors. Amino acid sequence of fluorescent proteins can be altered by genetic engineering to produce variants with different spectral properties, suitable for direct visualization of molecular and cellular processes. Naturally occurring GFP-like proteins include fluorescent proteins from cnidarians of the Hydrozoa and Anthozoa classes, and from copepods of the Pontellidae family, as well as non-fluorescent proteins from Anthozoa. Recently, an mRNA encoding a fluorescent GFP-like protein AmphiGFP, related to GFP from Pontellidae, has been isolated from the lancelet Branchiostoma floridae, a cephalochordate (Deheyn et al., Biol Bull, 2007 213:95). Results: We report that the nearly-completely sequenced genome of Branchiostoma floridae encodes at least 12 GFP-like proteins. The evidence for expression of six of these genes can be found in the EST databases. Phylogenetic analysis suggests that a gene encoding a GFP-like protein was present in the common ancestor of Cnidaria and Bilateria. We synthesized and expressed two of the lancelet GFP-like proteins in mammalian cells and in bacteria. One protein, which we called LanFP1, exhibits bright green fluorescence in both systems. The other protein, LanFP2, is identical to AmphiGFP in amino acid sequence and is moderately fluorescent. Live imaging of the adult animals revealed bright green fluorescence at the anterior end and in the basal region of the oral cirri, as well as weaker green signals throughout the body of the animal. In addition, red fluorescence was observed in oral cirri, extending to the tips. Conclusion GFP-like proteins may have been present in the primitive Metazoa. Their evolutionary history includes losses in several metazoan lineages and expansion in cephalochordates that resulted in the largest repertoire of GFP-like proteins known thus far in a single organism. Lancelet expresses several of its GFP-like proteins, which appear to have distinct spectral properties and perhaps diverse functions. Reviewers: This article was reviewed by Shamil Sunyaev, Mikhail Matz (nominated by I. King Jordan) and L. Aravind

Store-Operated Ca^(2+) Channels in Mesangial Cells Inhibit Matrix Protein Expression

Accumulation of extracellular matrix derived from glomerular mesangial cells is an early feature of diabetic nephropathy. Ca^(2+) signals mediated by store–operated Ca^(2+) channels regulate protein production in a variety of cell types. The aim of this study was to determine the effect of store–operated Ca^(2+) channels in mesangial cells on extracellular matrix protein expression. In cultured human mesangial cells, activation of store–operated Ca^(2+) channels by thapsigargin significantly decreased fibronectin protein expression and collagen IV mRNA expression in a dose-dependent manner. Conversely, inhibition of the channels by 2-aminoethyl diphenylborinate significantly increased the expression of fibronectin and collagen IV. Similarly, overexpression of stromal interacting molecule 1 reduced, but knockdown of calcium release–activated calcium channel protein 1 (Orai1) increased fibronectin protein expression. Furthermore, 2-aminoethyl diphenylborinate significantly augmented angiotensin II–induced fibronectin protein expression, whereas thapsigargin abrogated high glucose– and TGF-β1–stimulated matrix protein expression. In vivo knockdown of Orai1 in mesangial cells of mice using a targeted nanoparticle siRNA delivery system resulted in increased expression of glomerular fibronectin and collagen IV, and mice showed significant mesangial expansion compared with controls. Similarly, in vivo knockdown of stromal interacting molecule 1 in mesangial cells by recombinant adeno–associated virus–encoded shRNA markedly increased collagen IV protein expression in renal cortex and caused mesangial expansion in rats. These results suggest that store–operated Ca^(2+) channels in mesangial cells negatively regulate extracellular matrix protein expression in the kidney, which may serve as an endogenous renoprotective mechanism in diabetes

Automatic geolocation and measuring of offshore energy infrastructure with multimodal satellite data

With increasing trend of energy transition to low carbon economies, the rate of offshore structure installation and removal will rapidly accelerate through offshore renewable energy development and oil and gas decommissioning. Knowledge of the location and size of offshore infrastructure is vital in management of marine ecosystems, and also for safe navigation at sea. The availability of multimodal data enables the systematic assessment of offshore infrastructure. In this paper, we propose an automatic solution for the geolocation and size evaluation of offshore infrastructure through a data fusion model of Sentinel-1 Synthetic Aperture Radar (SAR) data and Sentinel-2 Multi-Spectral Instrument (MSI) imagery. The use of the Sentinel-1 (SAR) data aims to quick localization of the candidate offshore energy infrastructure by its all-weather imaging capabilities, while the high-resolution optical data provided by the Sentinel-2 can enable more accurate localization and measurement of the offshore infrastructure. To be specific, a candidate detection model is applied to a time-series of Sentinel-1 images to extract the ‘guided area’ of the infrastructure, followed by morphological operation based precise localization within an individual Sentinel-2 image as well as estimating the size of each structure. With validation against the ground truth data of the Scottish waters from the baseline and closing bays, to the limit of the Exclusive Economic Zone of Scotland, an area of 371,915 km2, our method has automatically identified 332 objects with an omission error of 0.3% and a commission rate of 0%. Our proposed method was comprehensively compared to two state-of-the-art offshore energy infrastructure detection algorithms. The results validate that our method achieves the highest overall accuracy of 99.70%, surpassing the compared methods by 3.84-12.50%. For the size evaluation, the achieved mean topside area size error of oil/gas platforms and the mean error for diameter length measurement of wind turbines both are 1 pixel in Sentinel-2 images, providing an effective technique for the identification and estimation of offshore infrastructure