Information Asymmetry in Mauritius Slave Auctions

Evidence on adverse selection in slave markets remains inconclusive. A necessary prerequisite is that buyers and sellers have different information. We study informational asymmetry on the slave markets through notarial acts on public slave auctions in Mauritius between 1825 and 1835, involving 4,286 slaves. In addition to slave characteristics, the acts document the identities of buyers and sellers. We use this information to determine whether the buyer of a slave was related (e.g. a relative or a spouse) to the original slave owner, and thus most likely better--informed than other bidders. Auction--theoretic models predict that bidding should be more aggressive when informed bidders are present in open-bid, ascending auctions, such as slave auctions. By proxying informed bidders by related bidders, our results consistently indicate that this is the case, pointing toward the presence of information asymmetry in the market for slaves in Mauritius

Asymmetric information and adverse selection in mauritian slave auctions

Information asymmetry is a necessary prerequisite for testing adverse selection. This paper applies this sequence of tests to Mauritian slave auctions. The theory of dynamic auctions with private and common values suggests that when an informed participant is known to be active, uninformed bidders will be more aggressive and the selling price will be higher. We conjecture that observable family links between buyer and seller entailed superior information and find a strong price premium when a related buyer purchased a slave, indicative of information asymmetry. We then test for adverse selection using sale motivation. Our results indicate large discounts on voluntary as compared to involuntary sales. Consistent with adverse selection, the market anticipated that predominantly low-productivity slaves would be brought to the market in voluntary sales

End-colostomy diverticulitis with parastomal phlegmon: A case report.

Acute colonic diverticulitis is a well-known surgical emergency, which occurs in about 10 percent of patients known for diverticulosis. The case of a 77-year-old woman is reported, with past history of abdominoperineal resection with end-colostomy for low rectal adenocarcinoma, and who developed an acute colonic diverticulitis in a subcutaneous portion of colostomy with parastomal phlegmon. Initial computed tomography imaging demonstrated a significant submucosal parietal edema with local fat tissues infiltration in regard of 3 diverticula. A two-step treatment was decided: first a nonoperative treatment was initiated with 2 weeks antibiotics administration, followed by, 6 weeks after, a segmental resection of the terminal portion of the colon with redo of a new colostomy by direct open approach. Patient was discharged on the second postoperative day without complications. Follow-up at 2 weeks revealed centimetric dehiscence of the stoma, which was managed conservatively until sixth postoperative week by stomatherapists. Treatment of acute diverticulitis with parastomal phlegmon in a patient with end-colostomy could primary be nonoperative. Delayed surgical treatment with segmental colonic resection was proposed to avoid recurrence and potential associated complications

BP and Heart Rate in Children with ADHD

OBJECTIVE: This study examines the effect of ADHD diagnosis and stimulant medication for ADHD treatment on child heart rate (HR) and blood pressure (BP) in a community sample compared to children without ADHD. METHODS: Data came from the HBEAT Study. 2,013 participants from 49 schools from southern Ontario in grades 5-8 were included. Linear regression analyses examined the effects of ADHD medications on systolic blood pressure, diastolic blood pressure, and heart rate adjusting for age, sex, and body mass index (BMI). RESULTS: Compared to non-ADHD children and adjusting for age, sex and BMI, children with ADHD on stimulant medication had a 12.3 bpm higher HR, and 3.0 mmHg higher SBP and DBP (all statistically significant). Children with ADHD on no stimulant medication had no differences in HR and BP compared to those children without a diagnosis of ADHD. CONCLUSION: Stimulant medications used to treat ADHD are associated with elevated HR and higher BP. While it is unknown if children on ADHD medications may be at risk for longer term cardiovascular issues, this study supports the need to examine the long-term consequences of ADHD medication

Holocene climate and environmental change in north-eastern Kamchatka (Russian Far East), inferred from a multi-proxy study of lake sediments

The study was supported by the Swedish Research Council through grants 621-2004-5224 and 621-2005-4444 to K.D. Bennett. A. Self and N. Solovieva acknowledge S. Brooks and V. Jones and were supported by NERC grant NE/H008160/1.A sediment record from a small lake in the north-eastern part of the Kamchatka Peninsula has been investigated in a multi-proxy study to gain knowledge of Holocene climatic and environmental change. Pollen, diatoms, chironomids and selected geochemical parameters were analysed and the sediment record was dated with radiocarbon. The study shows Holocene changes in the terrestrial vegetation as well as responses of the lake ecosystem to catchment maturity and multiple stressors, such as climate change and volcanic eruptions. Climate change is the major driving force resulting in the recorded environmental changes in the lake, although recurrent tephra deposition events also contributed. The sediment record has an age at the base of about 10,000 cal yrs BP, and during the first 400 years the climate was cold and the lake exhibited extensive ice-cover during winter and relatively low primary production. Soils in the catchment were poor with shrub alder and birches dominating the vegetation surrounding the lake. At about 9600–8900 cal yrs BP the climate was cold and moist, and strong seasonal wind stress resulted in reduced ice-cover and increased primary production. After ca. 8900 cal yrs BP the forest density increased around the lake, runoff decreased in a generally drier climate resulting in decreased primary production in the lake until ca. 7000 cal yrs BP. This generally dry climate was interrupted by a brief climatic perturbation, possibly attributed to the 8.2 ka event, indicating increasingly windy conditions with thick snow cover, reduced ice-cover and slightly elevated primary production in the lake. The diatom record shows maximum thermal stratification at ca. 6300–5800 cal yrs BP and indicates together with the geochemical proxies a dry and slightly warmer climate resulting in a high productive lake. The most remarkably change in the catchment vegetation occurred at ca. 4200 cal yrs BP in the form of a conspicuous increase in Siberian dwarf pine (Pinus pumila), indicating a shift to a cooler climate with a thicker and more long-lasting snow cover. This vegetational change was accompanied by marked shifts in the diatom and chironomid stratigraphies, which are also indicative of colder climate and more extensive ice-cover.Publisher PDFPeer reviewe

Absence of Ground States for a Class of Translation Invariant Models of Non-relativistic QED

We consider a class of translation invariant models of non-relativistic QED with net charge. Under certain natural assumptions we prove that ground states do not exist in the Fock space

A Comprehensive Review of Prognostic Factors in Patients with Gastric Adenocarcinoma.

Gastric adenocarcinoma remains associated with a poor long-term survival, despite recent therapeutical advances. In most parts of the world where systematic screening programs do not exist, diagnosis is often made at advanced stages, affecting long-term prognosis. In recent years, there is increasing evidence that a large bundle of factors, ranging from the tumor microenvironment to patient ethnicity and variations in therapeutic strategy, play an important role in patient outcome. A more thorough understanding of these multi-faceted parameters is needed in order to provide a better assessment of long-term prognosis in these patients, which probably also require the refinement of current staging systems. This study aims to review existing knowledge on the clinical, biomolecular and treatment-related parameters that have some prognostic value in patients with gastric adenocarcinoma

Holocene climate and environmental change in north-eastern Kamchatka (Russian Far East), inferred from a multi-proxy study of lake sediments

© 2015. A sediment record from a small lake in the north-eastern part of the Kamchatka Peninsula has been investigated in a multi-proxy study to gain knowledge of Holocene climatic and environmental change. Pollen, diatoms, chironomids and selected geochemical parameters were analysed and the sediment record was dated with radiocarbon. The study shows Holocene changes in the terrestrial vegetation as well as responses of the lake ecosystem to catchment maturity and multiple stressors, such as climate change and volcanic eruptions. Climate change is the major driving force resulting in the recorded environmental changes in the lake, although recurrent tephra deposition events also contributed. The sediment record has an age at the base of about 10,000. cal. yrs BP, and during the first 400 years the climate was cold and the lake exhibited extensive ice-cover during winter and relatively low primary production. Soils in the catchment were poor with shrub alder and birches dominating the vegetation surrounding the lake. At about 9600-8900. cal. yrs BP the climate was cold and moist, and strong seasonal wind stress resulted in reduced ice-cover and increased primary production. After ca. 8900 cal. yrs BP the forest density increased around the lake, runoff decreased in a generally drier climate resulting in decreased primary production in the lake until ca. 7000 cal. yrs BP. This generally dry climate was interrupted by a brief climatic perturbation, possibly attributed to the 8.2. ka event, indicating increasingly windy conditions with thick snow cover, reduced ice-cover and slightly elevated primary production in the lake. The diatom record shows maximum thermal stratification at ca. 6300-5800. cal. yrs BP and indicates together with the geochemical proxies a dry and slightly warmer climate resulting in a high productive lake. The most remarkably change in the catchment vegetation occurred at ca. 4200 cal. yrs BP in the form of a conspicuous increase in Siberian dwarf pine (Pinus pumila), indicating a shift to a cooler climate with a thicker and more long-lasting snow cover. This vegetational change was accompanied by marked shifts in the diatom and chironomid stratigraphies, which are also indicative of colder climate and more extensive ice-cover

Genetic Sequence Variation in the Plasmodium falciparum Histidine-Rich Protein 2 Gene from Field Isolates in Tanzania: Impact on Malaria Rapid Diagnosis

Malaria rapid diagnosis test (RDT) is crucial for managing the disease, and the effectiveness of detection depends on parameters such as sensitivity and specificity of the RDT. Several factors can affect the performance of RDT. In this study, we focused on the pfhrp2 sequence variation and its impact on RDTs targeted by antigens encoded by Plasmodium falciparum histidine-rich protein 2 (pfhrp2). Field samples collected during cross-sectional surveys in Tanzania were sequenced to investigate the pfhrp2 sequence diversity and evaluate the impact on HRP2-based RDT performance. We observed significant mean differences in amino acid repeats between current and previous studies. Several new amino acid repeats were found to occur at different frequencies, including types AAY, AHHAHHAAN, and AHHAA. Based on the abundance of types 2 and 7 amino acid repeats, the binary predictive model was able to predict RDT insensitivity by about 69% in the study area. About 85% of the major epitopes targeted by monoclonal antibodies (MAbs) in RDT were identified. Our study suggested that the extensive sequence variation in pfhrp2 can contribute to reduced RDT sensitivity. The correlation between the different combinations of amino acid repeats and the performance of RDT in different malaria transmission settings should be investigated further

Ground State and Resonances in the Standard Model of Non-relativistic QED

We prove existence of a ground state and resonances in the standard model of the non-relativistic quantum electro-dynamics (QED). To this end we introduce a new canonical transformation of QED Hamiltonians and use the spectral renormalization group technique with a new choice of Banach spaces.Comment: 50 pages change