Discrete sine transform for multi-scale realized volatility measures

In this study we present a new realized volatility estimator based on a combination of the multi-scale regression and discrete sine transform (DST) approaches. Multi-scale estimators similar to that recently proposed by Zhang (2006) can, in fact, be constructed within a simple regression-based approach by exploiting the linear relation existing between the market microstructure bias and the realized volatilities computed at different frequencies. We show how such a powerful multi-scale regression approach can also be applied in the context of the Zhou [Nonlinear Modelling of High Frequency Financial Time Series, pp. 109–123, 1998] or DST orthogonalization of the observed tick-by-tick returns. Providing a natural orthonormal basis decomposition of observed returns, the DST permits the optimal disentanglement of the volatility signal of the underlying price process from the market microstructure noise. The robustness of the DST approach with respect to the more general dependent structure of the microstructure noise is also shown analytically. The combination of the multi-scale regression approach with DST gives a multi-scale DST realized volatility estimator similar in efficiency to the optimal Cramer–Rao bounds and robust against a wide class of noise contamination and model misspecification. Monte Carlo simulations based on realistic models for price dynamics and market microstructure effects show the superiority of DST estimators over alternative volatility proxies for a wide range of noise-to-signal ratios and different types of noise contamination. Empirical analysis based on six years of tick-by-tick data for the S&P 500 index future, FIB 30, and 30 year U.S. Treasury Bond future confirms the accuracy and robustness of DST estimators for different types of real data

Synergistic effect p-phenylenediamine and n,n diphenylthiourea on the electrochemical corrosion behaviour of mild steel in dilute acid media

Electrochemical studies of the synergistic effect of p-phenylenediamine and n,n diphenylthiourea (TPD) as corrosion inhibitor of mild steel in dilute sulphuric and hydrochloric acid through weight loss and potentiodynamic polarization at ambient temperature were performed. Experimental results showed the excellent performance of TPD with an optimal inhibition efficiency of 88.18 and 93.88 %in sulphuric and 87.42 and 87.15 %in hydrochloric acid from both tests at all concentration studied. Polarization studies show the compound to be a mixed-type inhibitor. Adsorption of deanol on the steel surface was observed to obey the Langmuir and Frumkin isotherm models. X-ray diffractometry confirmed the absence of corrosion products and complexes. Optical microscopy confirmed the selective inhibition property of TPD to be through chemical adsorption on the steel surfac

Transcriptomics reveal an integrative role for maternal thyroid hormones during zebrafish embryogenesis

Thyroid hormones (THs) are essential for embryonic brain development but the genetic mechanisms involved in the action of maternal THs (MTHs) are still largely unknown. As the basis for understanding the underlying genetic mechanisms of MTHs regulation we used an established zebrafish monocarboxylic acid transporter 8 (MCT8) knock-down model and characterised the transcriptome in 25hpf zebrafish embryos. Subsequent mapping of differentially expressed genes using Reactome pathway analysis together with in situ expression analysis and immunohistochemistry revealed the genetic networks and cells under MTHs regulation during zebrafish embryogenesis. We found 4,343 differentially expressed genes and the Reactome pathway analysis revealed that TH is involved in 1681 of these pathways. MTHs regulated the expression of core developmental pathways, such as NOTCH and WNT in a cell specific context. The cellular distribution of neural MTH-target genes demonstrated their cell specific action on neural stem cells and differentiated neuron classes. Taken together our data show that MTHs have a role in zebrafish neurogenesis and suggest they may be involved in cross talk between key pathways in neural development. Given that the observed MCT8 zebrafish knockdown phenotype resembles the symptoms in human patients with Allan-Herndon-Dudley syndrome our data open a window into understanding the genetics of this human congenital condition.Portuguese Fundacao para Ciencia e Tecnologia (FCT) [PTDC/EXPL/MARBIO/0430/2013]; CCMAR FCT Plurianual financing [UID/Multi/04326/2013]; FCT [SFRH/BD/111226/2015, SFRH/BD/108842/2015, SFRH/BPD/89889/2012]; FCT-IF Starting Grant [IF/01274/2014]info:eu-repo/semantics/publishedVersio

Intracellular insulin in human tumors: examples and implications

Insulin is one of the major metabolic hormones regulating glucose homeostasis in the organism and a key growth factor for normal and neoplastic cells. Work conducted primarily over the past 3 decades has unravelled the presence of insulin in human breast cancer tissues and, more recently, in human non-small cell lung carcinomas (NSCLC). These findings have suggested that intracellular insulin is involved in the development of these highly prevalent human tumors. A potential mechanism for such involvement is insulin's binding and inactivation of the retinoblastoma tumor suppressor protein (RB) which in turn is likely controlled by insulin-degrading enzyme (IDE). This model and its supporting data are collectively covered in this survey in order to provide further insight into insulin-driven oncogenesis and its reversal through future anticancer therapeutics

Magnetism, FeS colloids, and Origins of Life

A number of features of living systems: reversible interactions and weak bonds underlying motor-dynamics; gel-sol transitions; cellular connected fractal organization; asymmetry in interactions and organization; quantum coherent phenomena; to name some, can have a natural accounting via $physical$ interactions, which we therefore seek to incorporate by expanding the horizons of `chemistry-only' approaches to the origins of life. It is suggested that the magnetic 'face' of the minerals from the inorganic world, recognized to have played a pivotal role in initiating Life, may throw light on some of these issues. A magnetic environment in the form of rocks in the Hadean Ocean could have enabled the accretion and therefore an ordered confinement of super-paramagnetic colloids within a structured phase. A moderate H-field can help magnetic nano-particles to not only overcome thermal fluctuations but also harness them. Such controlled dynamics brings in the possibility of accessing quantum effects, which together with frustrations in magnetic ordering and hysteresis (a natural mechanism for a primitive memory) could throw light on the birth of biological information which, as Abel argues, requires a combination of order and complexity. This scenario gains strength from observations of scale-free framboidal forms of the greigite mineral, with a magnetic basis of assembly. And greigite's metabolic potential plays a key role in the mound scenario of Russell and coworkers-an expansion of which is suggested for including magnetism.Comment: 42 pages, 5 figures, to be published in A.R. Memorial volume, Ed Krishnaswami Alladi, Springer 201

TonEBP/NFAT5 promotes obesity and insulin resistance by epigenetic suppression of white adipose tissue beiging

Tonicity-responsive enhancer binding protein (TonEBP or NFAT5) is a regulator of cellular adaptation to hypertonicity, macrophage activation and T-cell development. Here we report that TonEBP is an epigenetic regulator of thermogenesis and obesity. In mouse subcutaneous adipocytes, TonEBP expression increases > 50-fold in response to high-fat diet (HFD) feeding. Mice with TonEBP haplo-deficiency or adipocyte-specific TonEBP deficiency are resistant to HFD-induced obesity and metabolic defects (hyperglycemia, hyperlipidemia, and hyperinsulinemia). They also display increased oxygen consumption, resistance to hypothermia, and beiging of subcutaneous fat tissues. TonEBP suppresses the promoter of beta 3-adrenoreceptor gene, a critical regulator of lipolysis and thermogenesis, in ex vivo and cultured adipocytes. This involves recruitment of DNMT1 DNA methylase and methylation of the promoter. In human subcutaneous adipocytes TonEBP expression displays a correlation with body mass index but an inverse correlation with beta 3-adrenoreceptor expression. Thus, TonEBP is an attractive therapeutic target for obesity, insulin resistance, and hyperlipidemia

Memory for medication side effects in younger and older adults: the role of subjective and objective importance

Older adults often experience memory impairments, but can sometimes use selective processing and schematic support to remember important information. The current experiments investigate to what degree younger and healthy older adults remember medication side effects that were subjectively or objectively important to remember. Participants studied a list of common side effects, and rated how negative these effects were if they were to experience them, and were then given a free recall test. In Experiment 1, the severity of the side effects ranged from mild (e.g., itching) to severe (e.g., stroke), and in Experiment 2, certain side effects were indicated as critical to remember (i.e., “contact your doctor if you experience this”). There were no age differences in terms of free recall of the side effects, and older adults remembered more severe side effects relative to mild effects. However, older adults were less likely to recognize critical side effects on a later recognition test, relative to younger adults. The findings suggest that older adults can selectively remember medication side effects, but have difficulty identifying familiar but potentially critical side effects, and this has implications for monitoring medication use in older age

Absence of detection of RSV and influenza during the COVID-19 pandemic in a Brazilian cohort: Likely role of lower transmission in the community

Background: Respiratory syncytial virus (RSV) and influenza are prevalent seasonal community viruses. Although not completely understood, SARS-CoV-2 may have the same means of transmission. Preventive social measures aimed at preventing SARS-CoV-2 spread could impact transmission of other respiratory viruses as well. The aim of this study is to report the detection of RSV and influenza during the period of social distancing due to COVID-19 pandemic in a heavily affected community. Methods: Prospective study with pediatric and adult populations seeking care for COVID-19-like symptoms during the fall and winter of 2020 at two hospitals in Southern Brazil. RT-PCR tests for SARS-CoV-2, influenza A (Flu A), influenza B (Flu B) and respiratory syncytial virus (RSV) was performed for all participants. Results: 1435 suspected COVID-19 participants (1137 adults, and 298 children). were included between May and August. Median age was 37.7 years (IQR = 29.6-47.7), and 4.92 years (IQR = 1.96-9.53), for the adult and child cohorts, respectively. SARS-CoV-2 was positive in 469 (32.7%) while influenza and RSV were not detected at all. Conclusions: Measures to reduce SARS-CoV-2 transmission likely exerted a huge impact in the spread of alternate respiratory pathogens. These findings contribute to the knowledge about the dynamics of virus spread. Further, it may be considered for guiding therapeutic choices for these other viruses

The Present and Future Role of Insect-Resistant Genetically Modified Maize in IPM

Commercial, genetically-modified (GM) maize was first planted in the United States (USA, 1996) and Canada (1997) but now is grown in 13 countries on a total of over 35 million hectares (\u3e24% of area worldwide). The first GM maize plants produced a Cry protein derived from the soil bacteriumBacillus thuringiensis (Bt), which made them resistant to European corn borer and other lepidopteran maize pests. New GM maize hybrids not only have resistance to lepidopteran pests but some have resistance to coleopteran pests and tolerance to specific herbicides. Growers are attracted to the Btmaize hybrids for their convenience and because of yield protection, reduced need for chemical insecticides, and improved grain quality. Yet, most growers worldwide still rely on traditional integrated pest management (IPM) methods to control maize pests. They must weigh the appeal of buying insect protection “in the bag” against questions regarding economics, environmental safety, and insect resistance management (IRM). Traditional management of maize insects and the opportunities and challenges presented by GM maize are considered as they relate to current and future insect-resistant products. Four countries, two that currently have commercialize Bt maize (USA and Spain) and two that do not (China and Kenya), are highlighted. As with other insect management tactics (e.g., insecticide use or tillage), GM maize should not be considered inherently compatible or incompatible with IPM. Rather, the effect of GM insect-resistance on maize IPM likely depends on how the technology is developed and used

Early chronic kidney disease: diagnosis, management and models of care

Chronic kidney disease (CKD) is prevalent in many countries, and the costs associated with the care of patients with end-stage renal disease (ESRD) are estimated to exceed US$1 trillion globally. The clinical and economic rationale for the design of timely and appropriate health system responses to limit the progression of CKD to ESRD is clear. Clinical care might improve if early-stage CKD with risk of progression to ESRD is differentiated from early-stage CKD that is unlikely to advance. The diagnostic tests that are currently used for CKD exhibit key limitations; therefore, additional research is required to increase awareness of the risk factors for CKD progression. Systems modelling can be used to evaluate the impact of different care models on CKD outcomes and costs. The US Indian Health Service has demonstrated that an integrated, system-wide approach can produce notable benefits on cardiovascular and renal health outcomes. Economic and clinical improvements might, therefore, be possible if CKD is reconceptualized as a part of primary care. This Review discusses which early CKD interventions are appropriate, the optimum time to provide clinical care, and the most suitable model of care to adopt