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This paper studies the link between bank recapitalization and welfare in a dynamic production economy. The model features financial frictions because banks benefit of a cost advantage at monitoring firms and face costly equity issuance. The competitive equilibrium outcome is inefficient because agents do not internalize the effects banks’ capitalization over the allocation of capital, its price and, in turn, firms investments. It follows, individual recapitalizations are sub-optimal and bailout policies may benefit social welfare in the long-run. Bailouts improve capital allocation in states where aggregate banks are poorly capitalized, therefore enhancing their market valuation, fostering investments, and stabilizing the economy recovery path.
Market fragmentation and technological advances increasing the speed of trading altered the functioning and stability of global equity limit order markets. Taking market resiliency as an indicator of market quality, we investigate how resilient are trading venues in a high-frequency environment with cross-venue fragmented order flow. Employing a Hawkes process methodology on high-frequency data for FTSE 100 stocks on LSE, a traditional exchange, and on Chi-X, an alternative venue, we find that when liquidity becomes scarce Chi-X is a less resilient venue than LSE with variations existing across stocks and time. In comparison with LSE, Chi-X has more, longer, and severer liquidity shocks. Whereas the vast majority of liquidity droughts on both venues disappear within less than one minute, the recovery is not lasting, as liquidity shocks spiral over the time dimension. Over half of the shocks on both venues are caused by spiralling. Liquidity shocks tend to spiral more on Chi-X than on LSE for large stocks suggesting that the liquidity supply on Chi-X is thinner than on LSE. Finally, a significant amount of liquidity shocks spill over cross-venue providing supporting evidence for the competition for order flow between LSE and Chi-X.
Deep-water species from the western Indian Ocean off the East African coast and Madagascar, belonging to the subfamily Photinae, are discussed and compared with species from the West Pacific. Phos elegantissimus Hayashi & Habe, 1965, P. hirasei Sowerby, 1913 and P. laevis Kuroda & Habe in Habe, 1961 are recorded from Mozambique and/or from Madagascar, hereby extending their known range considerably into the western Indian Ocean. The East African specimens formerly assigned to Phos roseatus Hinds, 1844 are found to differ from this West Pacific species. In total, five species are described as new: Phos ganii sp. nov., P. geminus sp. nov., P. ladoboides sp. nov., P. pulchritudus sp. nov. and P. testaceus sp. nov.
Features of the Maechidiini (Scarabaeidae: Melolonthinae) genera Maechidius Macleay, 1819, Epholcis Waterhouse, 1875 and Paramaechidius Frey, 1969 are critically revised and a new synonymy is proposed: Maechidius = Epholcis syn. nov. = Paramaechidius syn. nov. A key to and an annotated checklist of Maechidiini from the Indo-Australian transition zone are presented for the first time. Thirty-five new species are described, namely Maechidius aiyura sp. nov., M. alesbezdeki sp. nov., M. awu sp. nov., M. babyrousa sp. nov., M. bintang sp. nov., M. boessnecki sp. nov., M. brocki sp. nov., M. caperatus sp. nov., M. ciliatus sp. nov., M. crypticus sp. nov., M. dani sp. nov., M. deltouri sp. nov., M. dendrolagus sp. nov., M. hamatus sp. nov., M. kazantsevi sp. nov., M. konjo sp. nov., M. lapsus sp. nov., M. legalovi sp. nov., M. leucopsar sp. nov., M. longipes sp. nov., M. mailu sp. nov., M. maleo sp. nov., M. merdeka sp. nov., M. miklouhomaclayi sp. nov., M. nepenthephilus sp. nov., M. owenstanleyi sp. nov., M. riedeli sp. nov., M. similis sp. nov., M. skalei sp. nov., M. sougb sp. nov., M. suwawa sp. nov., M. trivialis sp. nov., M. ursus sp. nov., M. weigeli sp. nov. and M. yamdena sp. nov. Six new synonyms are proposed: Maechidius Macleay, 1819 = Epholcis Waterhouse, 1875 syn. nov. = Paramaechidius Frey, 1969 syn. nov., Maechidius esau Heller, 1914 = M. setosus Moser, 1920 syn. nov. = M. setosellus Frey, 1969 syn. nov., Maechidius heterosquamosus Heller, 1910 comb. rest. = Paramaechidius clypeatus Frey, 1969 syn. nov. and Maechidius paupianus Heller, 1910 = M. arrowi Frey, 1969 syn. nov. The first records of Maechidiini from the Tanimbar Islands (Yamdena), Sangihe Islands (Sangir) and Lesser Sunda Islands (Bali) are documented, of which the latter two are the northern- and westernmost known records of Maechidius and of the tribe Maechidiini. Lectotypes are designated for 23 species. Fifteen new combinations are proposed and the original combination to Maechidius is restored for four species. Ecological data are presented for the first time for selected Papuan and Wallacean species. Type material of Wallacean and Papuan Maechidiini is depicted for the first time. A key to species is given. In total, 78 species of Maechidiini are confirmed for the Indo-Australian transition zone.
This study reports and discusses new radiometric ages, petrographical and volcanological observations and whole rock geochemical data of the rocks of the Rudnik Mts. volcano-intrusive complex. The complex hosts a Pb-Zn-Ag deposit and belongs to the Serbo-Macedonian metallogenetic belt. Two distinct igneous events are distignuished. The first occurred >30 Ma and was mainly characterized by extrusive and shallow intrusive dacites and andesites and was unrelated to mineralization. The second igneous event occurred <23 Ma and was highly heterogeneous in terms of volcanic products and petrographic varieties, but with predominance of quartzlatites. The dacite-andesites (first event) and the quartzlatites (second event) are geochemically similar and display a calc-alkaline affinity and highly incompatible element enriched patterns on spider diagrams, but the younger quartzlatites are richer in K2O, Rb and Ba and poorer in Sr. This is taken as evidence that mixing between an ultrapotassic lamprophyre/lamproite magma and an acid calc-alkaline (dacite-like) magma was essential petrogenetic processes during the second event. The proposed simplified volcanological model suggests that this mixing was responsible for triggering strongly explosive volcanic activity as well as for providing conditions for active hydrothermal and mineralization processes. The observed link between a specific magmatic phase and ore deposit formation can be a general phennomenon in the Balkans, and must be addressed by further and more advanced studies.
The impact of columnar file formats on SQL‐on‐hadoop engine performance: a study on ORC and Parquet
(2019)
Columnar file formats provide an efficient way to store data to be queried by SQL‐on‐Hadoop engines. Related works consider the performance of processing engine and file format together, which makes it impossible to predict their individual impact. In this work, we propose an alternative approach: by executing each file format on the same processing engine, we compare the different file formats as well as their different parameter settings. We apply our strategy to two processing engines, Hive and SparkSQL, and evaluate the performance of two columnar file formats, ORC and Parquet. We use BigBench (TPCx‐BB), a standardized application‐level benchmark for Big Data scenarios. Our experiments confirm that the file format selection and its configuration significantly affect the overall performance. We show that ORC generally performs better on Hive, whereas Parquet achieves best performance with SparkSQL. Using ZLIB compression brings up to 60.2% improvement with ORC, while Parquet achieves up to 7% improvement with Snappy. Exceptions are the queries involving text processing, which do not benefit from using any compression.
The detection of cortical malformations in conventional MR images can be challenging. Prominent examples are focal cortical dysplasias (FCD), the most common cause of drug‐resistant focal epilepsy. The two main MRI hallmarks of cortical malformations are increased cortical thickness and blurring of the gray (GM) and white matter (WM) junction. The purpose of this study was to derive synthetic anatomies from quantitative T1 maps for the improved display of the above imaging characteristics in individual patients.
On the basis of a T1 map, a mask comprising pixels with T1 values characteristic for GM is created from which the local cortical extent (CE) is determined. The local smoothness (SM) of the GM‐WM junctions is derived from the T1 gradient. For display of cortical malformations, the resulting CE and SM maps serve to enhance local intensities in synthetic double inversion recovery (DIR) images calculated from the T1 map.
The resulting CE‐ and/or SM‐enhanced DIR images appear hyperintense at the site of cortical malformations, thus facilitating FCD detection in epilepsy patients. However, false positives may arise in areas with naturally elevated CE and/or SM, such as large GM structures and perivascular spaces.
In summary, the proposed method facilitates the detection of cortical abnormalities such as cortical thickening and blurring of the GM‐WM junction which are typical FCD markers. Still, subject motion artifacts, perivascular spaces, and large normal GM structures may also yield signal hyperintensity in the enhanced synthetic DIR images, requiring careful comparison with clinical MR images by an experienced neuroradiologist to exclude false positives.
Signal transduction and the regulation of gene expression are fundamental processes in every cell. RNA-binding proteins (RBPs) play a key role in the post-transcriptional modulation of gene expression in response to both internal and external stimuli. However, how signaling pathways regulate the assembly of RBPs with mRNAs remains largely unknown. Here, we summarize observations showing that the formation and composition of messenger ribonucleoprotein particles (mRNPs) is dynamically remodeled in space and time by specific signaling cascades and the resulting post-translational modifications. The integration of signaling events with gene expression is key to the rapid adaptation of cells to environmental changes and stress. Only a combined approach analyzing the signal transduction pathways and the changes in post-transcriptional gene expression they cause will unravel the mechanisms coordinating these important cellular processes.
Postoperative thrombotic thrombocytopenic purpura (TTP) shows clinical presentation similar to classical TTP, whereas exact pathophysiological contexts remain unexplained. In this study, we investigated intraoperative and postoperative changes in ADAMTS-13 (a disintegrin and metalloprotease with thrombospondin type 1 motifs, member 13), von Willebrand factor (VWF), large VWF multimers, and interleukin-6 (IL-6) in vascular surgery patients. The objective was to compare the impact of endovascular, peripheral, and aortic surgery on target parameters which are supposed to play a role in surgery-associated TTP. A total of 93 vascular surgery patients were included and divided into 4 groups according to the specific type of intervention they underwent. Blood samples were taken preoperatively, intraoperatively, and postoperatively on days 2 and 4. The ADAMTS-13 activity decreased significantly in 3 of the 4 groups during surgery (from median 81% to 49%, P < .001, in the group undergoing aortoiliacal interventions), whereas the percentage of large VWF multimers increased in all groups of patients. von Willebrand factor antigen increased significantly in all groups on postoperative day 2 and IL-6 increased significantly in the intraoperative and early postoperative period. There was no significant correlation between the intraoperative decrease in ADAMTS-13 and the increase in VWF or IL-6. No patient in this study showed clinical picture of TTP; the precise cause and clinical significance of moderately reduced ADAMTS-13 activity in the perioperative setting have not yet been definitely determined.
Background: Macrophage Migration Inhibitory Factor (MIF) is highly elevated after cardiac surgery and impacts the postoperative inflammation. The aim of this study was to analyze whether the polymorphisms CATT5–7 (rs5844572/rs3063368,“-794”) and G>C single-nucleotide polymorphism (rs755622,-173) in the MIF gene promoter are related to postoperative outcome. Methods: In 1116 patients undergoing cardiac surgery, the MIF gene polymorphisms were analyzed and serum MIF was measured by ELISA in 100 patients. Results: Patients with at least one extended repeat allele (CATT7) had a significantly higher risk of acute kidney injury (AKI) compared to others (23% vs. 13%; OR 2.01 (1.40–2.88), p = 0.0001). Carriers of CATT7 were also at higher risk of death (1.8% vs. 0.4%; OR 5.12 (0.99–33.14), p = 0.026). The GC genotype was associated with AKI (20% vs. GG/CC:13%, OR 1.71 (1.20–2.43), p = 0.003). Multivariate analyses identified CATT7 predictive for AKI (OR 2.13 (1.46–3.09), p < 0.001) and death (OR 5.58 (1.29–24.04), p = 0.021). CATT7 was associated with higher serum MIF before surgery (79.2 vs. 50.4 ng/mL, p = 0.008). Conclusion: The CATT7 allele associates with a higher risk of AKI and death after cardiac surgery, which might be related to chronically elevated serum MIF. Polymorphisms in the MIF gene may constitute a predisposition for postoperative complications and the assessment may improve risk stratification and therapeutic guidance.