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Background/Aim: Renin-angiotensin system (RAS) is present in a diverse type of cells and plays an important role in lung physiology and pathophysiology. Angiotensin converting enzymes (ACE) are part of the RAS system. There are still controversies about the association of I/D polymorphisms of ACE1 with COVID-19 severity. The goal of the study was to determine whether there is an association of the I/D polymorphism with severity of COVID-19 in Mexican patients. Patients and Methods: The study included voluntary participants: 53 healthy individuals negative to RT-PCR COVID-19 (control), and 165 patients positive to COVID-19. Severity was defined by the need of hospitalization, invasive ventilation, shock, or multiple organ failure. The patient group consisted of 28 asymptomatic, 82 with mild, and 55 with severe COVID-19. I/D polymorphism was determined by PCR. Rutinary laboratory tests were performed in all the participants. Results: DD polymorphism was significantly associated with severe COVID-19, independently of comorbidities, or any other variable. Receiver operator characteristic curves demonstrated association of low total cholesterol, low high-density lipoproteins, and high c-reactive protein with severity of COVID-19. Conclusion: The DD polymorphism was associated with the course of the infection and severity of COVID-19 in a sample of Mexican patients.

Bajo la premisa de que el Estado es una unidad que se gobierna permanentemente por sí misma, que no tiene sobre él ninguna autoridad terrenal, con excepción al sistema internacional público, que posee el monopolio del ejercicio de la fuerza, para lo cual usa la coerción legítima que le permite efectivizar las decisiones adoptadas, la supremacía en el control de la fuerza pública y de algunas agencias especializadas del mismo Estado que normalmente ejerce control sobre el territorio, se pretende en este capítulo describir el funcionamiento del sistema de separación de poderes en Colombia, a partir de la promulgación de la Constitución de 1991 y analizar los avances del Estado colombiano en la consolidación de un sistema democrático participativo y eficiente.

This article studies the optimal design of corporate taxes when firms have private information about future investment opportunities and face financial constraints. A government whose goal is to efficiently raise a given amount of revenue from its corporate sector should attempt to tax unconstrained firms, which value resources inside the firm less than financially constrained firms. We show that a corporate payout tax (a tax on dividends and share repurchases) can both separate constrained and unconstrained firms and raise revenue and is therefore optimal. Our quantitative analysis implies that a revenue-neutral switch from profit taxation to payout taxation would increase the overall value of existing firms and new entrants by $7\%$. This switch could be implemented in the current US tax system by making retained earnings fully deductible.

The risk of coronavirus disease 2019 (COVID-19) and dengue coinfection is increased in tropical countries; however, the extrapulmonary clinical manifestations have not been fully characterized. We report a 42-year-old woman whose clinical manifestations began with fever, diarrhea, headache, chest pain, myalgia, odynophagia, and arthralgia. Despite mild respiratory symptoms and normal chest computed tomography scan results, she was diagnosed with real-time reverse-transcription polymerase chain reaction (RT-PCR)-confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Because she had erythema and petechiae with a decreased platelet count, the dengue NS1 antigen and anti-dengue IgM/IgG test were performed, and the Centers for Disease Control and Prevention RT-PCR assay detected the dengue virus serotype 1 infection. Additionally, increased liver enzyme serum levels were found in the patient, who later developed hepatomegaly. Hence, the mechanism of hepatic pathology associated with SARS-CoV-2 and dengue coinfection needs further research.

Highlights • The first published case of newborn infant SARS-CoV-2 infection in Mexico. • SARS-CoV-2 RNA is detected in Human Breast Milk and Stool. • The intrauterine infection and breastfeeding could be mechanisms for vertical transmission of SARS-CoV-2., Although COVID-19 in pregnant women and their neonates has been demonstrated, there is not enough evidence about how this vertical transmission occurs. This report describes a SARS-CoV-2 infection in a 21-year-old mother-daughter duo at the time of birth, focusing on the viral RNA detection in the stool of both and the human breast milk.

We explore how large and small banks make funding decisions when system-wide bailouts are possible. We show that bank size, purely on strategic grounds, is a key determinant of banks’ leverage choices, even when bailout policies treat large and small banks symmetrically. Large banks leverage more than small banks because they internalize that their decisions directly affect bailout policies. In equilibrium, this effect is amplified by strategic spillovers to small banks since banks’ leverage choices are strategic complements. Overall, the presence of large banks makes bailouts more likely. The optimal regulation features size-dependent policies that disproportionately restrict large banks’ leverage.

This paper studies the optimal design of second-best corrective regulation, when some agents or activities cannot be perfectly regulated. We show that policy elasticities and Pigouvian wedges are sufficient statistics to characterize the marginal welfare impact of regulatory policies in a large class of environments. We show that the optimal second-best policy is determined by a subset of policy elasticities: leakage elasticities, and characterize the marginal value of relaxing regulatory constraints. We apply our results to scenarios with unregulated agents/activities and with uniform regulation across agents/activities. We illustrate our results in applications to shadow banking, scale-invariant regulation, asset substitution, and fire sales. Institutional subscribers to the NBER working paper series, and residents of developing countries may download this paper without additional charge at www.nber.org.

This paper studies leverage regulation and monetary policy when equity investors and/or creditors have distorted beliefs relative to a planner. We characterize how the optimal leverage regulation responds to arbitrary changes in investors' and creditors' beliefs and relate our results to practical scenarios. We show that the optimal regulation depends on the type and magnitude of such changes. Optimism by investors calls for looser leverage regulation, while optimism by creditors, or jointly by both investors and creditors, calls for tighter leverage regulation. Monetary policy should be tightened (loosened) in response to either investors' or creditors' optimism (pessimism).

We study the relationship between homebuyers’ beliefs about future house price changes and their mortgage leverage choices. Whether more pessimistic homebuyers choose higher or lower leverage depends on their willingness and ability to reduce the size of their housing market investments. When households primarily maximize the levered return of their property investments, more pessimistic homebuyers reduce their leverage to purchase smaller houses. On the other hand, when considerations such as family size pin down the desired property size, pessimistic homebuyers reduce their financial exposure to the housing market by making smaller downpayments to buy similarly-sized homes. To determine which scenario better describes the data, we investigate the cross-sectional relationship between house price beliefs and mortgage leverage choices in the U.S. housing market. We use plausibly exogenous variation in house price beliefs to show that more pessimistic homebuyers make smaller downpayments and choose higher leverage, in particular in states where default costs are relatively low, as well as during periods when house prices are expected to fall on average. Our results highlight the important role of heterogeneous beliefs in explaining households’ financial decisions.

This paper studies the optimal determination of deposit insurance when bank runs are possible. We show that the welfare impact of changes in the level of deposit insurance coverage can be generally expressed in terms of a small number of sufficient statistics, which include the level of losses in specific scenarios and the probability of bank failure. We characterize the wedges that determine the optimal ex-ante regulation, which map to asset- and liability-side regulation. We demonstrate how to employ our framework in an application to the most recent change in coverage, which took place in 2008.

This paper characterizes the optimal transaction tax in an equilibrium model of competitive financial markets. As long as investors hold heterogeneous beliefs that are not related to their fundamental trading motives and the planner calculates welfare using any single belief, a strictly positive tax is optimal, regardless of the magnitude of fundamental trading. Under some conditions, the optimal tax is independent of the belief used by the planner to calculate welfare. The optimal tax can be implemented by adjusting its value until observed total volume equals fundamental volume. Knowledge of i) the share of non-fundamental trading volume and ii) the semi-elasticity of trading volume to tax changes is sufficient to quantify the optimal tax. A calibration of the model consistent with empirically estimated volume semi-elasticities to tax changes and that features a 30% share of non-fundamental trading volume is associated with a 37bps optimal tax. Institutional subscribers to the NBER working paper series, and residents of developing countries may download this paper without additional charge at www.nber.org.

espanolLa innovacion tiende a mejorar el proceso productivo dentro de una empresa, aquello que pueda ser mas atractivo y presentable, que proporcione cambios e introduzca novedades para lograr los objetivos y metas planteadas. En el contexto actual es necesario el estimulo al cambio. Este trabajo investigativo se enfoco en determinar la influencia de la innovacion en el proceso productivo de la estacion de servicios Ines Galeano, en el periodo 2018. Para realizar este tipo de estudio se tomo en cuenta la metodologia, que consiste en buscar las fuentes mas creibles como es la Bibliografia en la Biblioteca Urania Zelaya, FAREM-Esteli, Libros, tesis relacionadas con el tema, libros en la pagina web. Se analizo el impacto que han tenido las mejoras aplicadas a los elementos mas importantes de los procesos de trabajo que se realizan en la organizacion, en los servicios que se ofertan. Es una investigacion aplicada, de caracter descriptivo y se enmarca metodologicamente en un enfoque mixto y de corte transversal. La muestra la constituyeron los 22 colaboradores que forman parte de la empresa. Para la recoleccion de esta informacion, fue necesaria la utilizacion de instrumentos como encuestas y entrevistas, la cual sirvio como base para conocer los problemas existentes en dicho lugar. Este estudio se baso en el supuesto el cual sugiere que la innovacion, contribuye al proceso productivo de la empresa. Los principales resultados se enfocan en lo siguiente: se establece la influencia de la innovacion en el proceso productivo, es decir de que manera han aportado los cambios innovadores en los procesos de trabajo de la empresa y se describe las innovaciones en los aspectos mas relevantes de sus servicios, asi como se identificaron los beneficios de las mejoras aplicadas en los aspectos mas relevantes de la organizacion. EnglishInnovation tends to improve the production process within a company, which can be more attractive and presentable which provides changes and introduces novelties to achieve the goals and objectives set. In the current context, stimulation of change is necessary. This research focused on determining the influence of innovation on the production process of the Ines Galeano service station, in the year 2018. To carry out this type of study, the methodology was taken into account, which consists of looking for the most credible sources such as the Bibliography in the Urania Zelaya Library, FAREM-Esteli, Books, thesis related to the subject, books on the website. The impact of the improvements applied to the most important elements of the work processes that are carried out in the organization, on the services that are offered, was analyzed. It is an applied, descriptive research and is methodologically framed in a mixed and cross-sectional approach. The sample was made up of the 22 collaborators who are part of the company. For the collection of this information, it was necessary to use tools such as surveys and interviews, which served as the basis for knowing the problems existing there. This study was based on the assumption which suggests that innovation contributes to the company’s production process. The main results focus on the following: it establishes the influence of innovation in the production process, i.e. how innovative changes in the company’s work processes have been brought and the innovations in the aspects the most relevant aspects of its services were identified, as well as the benefits of the improvements applied in the most relevant aspects of the organization.

Edgar Calel (1987) é um artista Maya kaqchikel da Guatemala. Sua prática artística, pautada pela mobilidade e pelo movimento, lida com temas ligados à migração, ao deslocamento e ao retorno. Originário de Comalapa, Calel saiu de sua cidade natal para estudar arte, fazendo de sua vida uma jornada. Neste ensaio visual são apresentados registros de algumas séries como Yo vivo en ti, Tú vives en mi; B ́atz – tejido constelación de saberes; Ixim (Maíz); e Laberinto de los Pájaros. O ensaio se encerra com o texto Memoria del movimiento, de Sebastián Eduardo [Dávila].

This paper studies the optimal determination of deposit insurance (DI) when bank runs are possible. In a variety of environments, the welfare impact of changes in the level of deposit insurance coverage exclusively depends on three sufficient statistics: the sensitivity of the likelihood of bank failure with respect to the level of DI, the utility gain induced by preventing the marginal bank failure, which can be expressed in terms of the drop in depositors' consumption, and the direct social cost of intervention in bank failure scenarios, which can be expressed in terms of the probability of bank failure, the marginal cost of public funds, and the mass of partially insured depositors. The same expression applies a) when banks face perfect ex-ante regulation and b) when banks are not allowed to react to policy changes. Under imperfect regulation, because banks do not internalize the fiscal impact of their actions, changes in the behavior of banks induced by varying the level of DI (often referred to as moral hazard) only affect the level of optimal DI directly through a fiscal externality, but not independently. We characterize the wedges that determine the optimal ex-ante regulation, which map to liability-side regulation (e.g., deposit insurance premia) and asset-side regulation. Finally, we explore the quantitative implications of our approach through a direct measurement exercise and a model simulation.

This paper studies financial and monetary policy in environments in which equity investors and creditors may have distorted beliefs. We characterize conditions under which it is optimal to tighten or relax leverage caps in response to arbitrary changes in beliefs. The optimal policy response to belief distortions depends on the type as well as the extent of exuberance, and it is not generally true that regulators should lean against the wind by tightening leverage caps in response to optimism. We show that increased optimism by investors is associated with relaxing the optimal leverage cap, while increased optimism by creditors, or jointly by both investors and creditors is associated with a tighter optimal leverage cap. In the presence of government bailouts, increased optimism by equity investors may call for a tighter optimal leverage cap too, depending on whether equity optimism is concentrated on upside or downside risk. Increased optimism by either equity investors or creditors is associated with higher incentives to raise interest rates, so monetary tightening can act as a useful substitute for financial regulation.

This article characterizes the efficiency properties of competitive economies with financial constraints, in which phenomena such as fire sales and financial amplification may arise. We show that financial constraints lead to two distinct types of pecuniary externalities: distributive externalities that arise from incomplete insurance markets and collateral externalities that arise from price-dependent financial constraints. For both types of externalities, we identify three sufficient statistics that determine optimal taxes on financing and investment decisions to implement constrained efficient allocations. We also show that fire sales and financial amplification are neither necessary nor sufficient to generate inefficient pecuniary externalities. We demonstrate how to employ our framework in a number of applications. Whereas collateral externalities generally lead to over-borrowing, the distortions from distributive externalities may easily flip sign, leading to either under- or over-borrowing. Both types of externalities may lead to under- or over-investment.

This article studies the optimal determination of bankruptcy exemptions for risk averse borrowers who use unsecured contracts but have the possibility of defaulting. In a large class of economies, knowledge of four variables is sufficient to determine whether a bankruptcy exemption level is optimal or should be increased or decreased. These variables are 1. the composition of households’ liabilities, 2. the sensitivity of the credit supply schedule to exemption changes, 3. the probability of filing for bankruptcy with non-exempt assets, and 4. the value given by households to a marginal dollar in different states, which can be mapped to changes in households’ consumption. I recover empirical estimates of the sufficient statistics using U.S. data over the period 2008–16 and find that increasing exemption levels improves overall welfare, although there is substantial variation in estimated welfare gains across U.S. states and income quintiles.

This paper studies the effect of trading costs on information diffusion and information acquisition in financial markets. For a given precision of investors' private information, an irrelevance result emerges when investors are ex-ante identical: the level of trading costs does not affect price informativeness or price volatility. This result holds independently of whether investors behave competitively or strategically and applies to both static and dynamic economies. When investors are ex-ante heterogeneous, trading costs affect price informativeness if and only if investors who disproportionately trade on information are more elastic than investors who mostly trade due to hedging. Trading costs always reduce information acquisition, even when price informativeness remains unchanged for a given amount of information. Our results matter to understand a) the consequences of cheaper financial trading and b) the effects of transaction taxes.

We explore the equilibrium relation between price volatility and price informativeness in financial markets, with the ultimate goal of characterizing the type of inferences that can be drawn about price informativeness by observing price volatility. We identify two different channels (noise reduction and equilibrium learning) through which changes in price informativeness are associated with changes in price volatility. We show that when informativeness is sufficiently high (low) volatility and informativeness positively (negatively) comove in equilibrium for any change in primitives. In the context of our leading application, we provide conditions on primitives that guarantee that volatility and informativeness always comove positively or negatively. We use data on U.S. stocks between 1963 and 2017 to recover stock-specific primitives and find that most stocks lie in the region of the parameter space in which informativeness and volatility comove negatively.

This paper studies the optimal design of corporate taxes when firms have private information about future investment opportunities and face financial constraints. A government whose goal is to efficiently raise a given amount of revenue from its corporate sector should attempt to tax unconstrained firms, which value resources inside the firm less than financially constrained firms. We show that a corporate payout tax (a tax on dividends and share repurchases) can both separate constrained and unconstrained firms and raise revenue, and is therefore optimal. Our quantitative analysis implies that a revenue-neutral switch from profit taxation to payout taxation would increase the overall value of existing firms and new entrants by 7%. This switch could be implemented in the current U.S. tax system by making retained earnings fully deductible.

We show that outcomes (parameter estimates and R-squareds) of regressions of prices on fundamentals allow us to recover exact measures of the ability of asset prices to aggregate dispersed information. Formally, we show how to recover absolute and relative price informativeness in dynamic environments with rich heterogeneity across investors (regarding signals, private trading needs, or preferences), minimal distributional assumptions, multiple risky assets, and allowing for stationary and non-stationary asset payoffs. We implement our methodology empirically, finding stock-specific measures of price informativeness for U.S. stocks. We find a right-skewed distribution of price informativeness, measured in the form of the Kalman gain used by an external observer that conditions its posterior belief on the asset price. The recovered mean and median are 0.05 and 0.02 respectively. We find that price informativeness is higher for stocks with higher market capitalization and higher trading volume.

We study the relationship between homebuyers’ beliefs about future house price changes and their mortgage leverage choices. Whether more pessimistic homebuyers choose higher or lower leverage depends on their willingness and ability to reduce the size of their housing market investments. When households primarily maximize the levered return of their property investments, more pessimistic homebuyers reduce their leverage to purchase smaller houses. On the other hand, when considerations such as family size pin down the desired property size, pessimistic homebuyers reduce their financial exposure to the housing market by making smaller downpayments to buy similarly-sized homes. To determine which scenario better describes the data, we investigate the cross-sectional relationship between house price beliefs and mortgage leverage choices in the U.S. housing market. We use plausibly exogenous variation in house price beliefs to show that more pessimistic homebuyers make smaller downpayments and choose higher leverage, in particular in states where default costs are relatively low, as well as during periods when house prices are expected to fall on average. Our results highlight the important role of heterogeneous beliefs in explaining households’ financial decisions

We study the effect of trading costs on information aggregation and information acquisition in financial markets. For a given precision of investors’ private information, an irrelevance result emerges when investors are ex-ante identical: price informativeness does not depend on the level of trading costs. This result holds independently of whether trading costs are quadratic or linear, investors behave competitively or strategically, and applies to both static and dynamic economies. When investors are ex-ante heterogeneous, trading costs reduce (increase) price informativeness if and only if investors who disproportionately trade on information are more (less) elastic than investors who mostly trade due to hedging. Trading costs always reduce information acquisition and consequently price informativeness, even when price informativeness remains unchanged for a given amount of information. Our results matter to understand the consequences of cheaper financial trading and the effects of financial transaction taxes.

International audience; We present a prototype software to virtually deploy pipeline fl ow diverting stents in intracranial vessels with aneurysms. The fi nal objective is to understand the biological and biomechanical mechanisms underlying the stent-induced clot formation within the aneurysm. The weaving pattern of the selected pipeline stent is described w.r.t. cylindrical coordinates. Patient-speci fic 3D vascular geometry is extracted by a level-set image segmentation algorithm. A deformable cylindrical simplex mesh model is used to simulate the virtual stent positioning. A continuous Right Generalized Cylinder model is then used to obtain the mapping of the stent geometry onto the deformed cylindrical surface. Meshes representing the vessel/aneurysm surface and the fi laments of the stent are used as input to simulate the fl uid dynamics without and with the virtual stent. Lattice Boltzmann method is used to solve the equations. We show preliminary visual results on a first patient.

BACKGROUND Central giant cell granuloma (CGCG) of the jaws is a rare benign tumour with an unknown aetiology accounting for up to 7% of tumours in the mandible (lower jaw) and the maxilla (upper jaw). OBJECTIVES This systematic review focused on assessing the effects of primary non-surgical versus primary surgical interventions or any other treatment or placebo for treating central giant cell granuloma of the jaws. SEARCH STRATEGY Relevant randomised controlled trials (RCTs) were identified from the Cochrane Oral Health Group's Trials Register (July 2009); CENTRAL (The Cochrane Library 2009, Issue 3); MEDLINE (1950 to July 2009); EMBASE (1980 to July 2009); and LILACS (1982 to July 2009). We scanned bibliographies of relevant studies for possible references to additional trials as well as prospective clinical trial registries. Eligible RCTs were included regardless of the language of publication. SELECTION CRITERIA Randomised controlled trials involving a comparison of primary non-surgical interventions with primary surgical interventions or any other treatment. DATA COLLECTION AND ANALYSIS Two review authors independently assessed eligibility, risk of bias and extracted data. The Cochrane Collaboration statistical guidelines were followed. MAIN RESULTS We did not find any study evaluating the effects of primary surgical versus primary non-surgical interventions for central giant cell granuloma of the jaws. However, we included and analysed one RCT with unclear risk of bias, evaluating the effects of calcitonin versus placebo for central giant cell granuloma of the jaws. No significant difference was found in the proportion of patients with increased volume of more than 10% of the lesion compared to the pretreatment measurement at 3 months of follow-up (one RCT, 14 participants; risk ratio (RR) 3.00, 95% confidence interval (CI) 0.40 to 22.30). AUTHORS' CONCLUSIONS We did not find RCTs evaluating the effects of primary surgical versus primary non-surgical interventions for central giant cell granuloma of the jaws. Although a number of non-surgical therapies have been proposed for treating central giant cell granuloma of the jaws, our review did not identify evidence from RCTs to support their use. More research is needed on this topic.

Se determino la distribucion espacial de los bosques dominados Colombobalanus excelsa en el Parque Nacional Natural (PNN) Cueva de los Guacharos y su zona de amortiguacion y se precisaron sus parametros estructurales utilizando un inventario forestal estratificado. El inventario se realizo en cuatro fajas de 0.5 ha distribuidas en dos estratos: el primer estrato se localizo en el PNN Cueva de los Guacharos y el segundo en su zona de amortiguacion. Cada faja estuvo conformada por parcelas de 20 x 50 m para registrar individuos con diametros a la altura del pecho (DAP) = 10 cm, altura total, diametro de copa y estado del arbol; asimismo, en cada faja se anido una subparcela de 10 x 10 m para registrar individuos con DAP = 10 cm y alturas mayores a 3 m y el numero de plantulas = 0.3 m de altura se estimo en subparcelas de 5 x 5 m. Se generaron modelos para estimar la altura y el volumen en funcion del DAP. Se reportaron un total de ocho rodales naturales de roble negro que alcanzaban las 2000 ha, de las cuales 28.3 ha se encontraron dentro del parque. Se registro una densidad de 281.7 arboles ha -1 , un area basal de 52.33 m 2 ha -1 y un volumen de 761.65 m 3 ha -1 . El factor morfico para la especie fue de 0.76041. Se ajustaron seis modelos para estimar la altura y seis para volumen con ajustes de 0.90 y 0.98, respectivamente.