Significant interstellar object production by close stellar flybys

Within just two years, two interstellar objects (ISOs) - Oumuamuas and Borisov - have been discovered. Large quantities of planetesimals form as a by-product of planet formation. Therefore, it seems likely that ISOs are former planetesimals that became unbound from their parent star. The discoveries raise the question of the dominant ISO formation process. Here, we concentrate on planetesimals released during another star's close flybys. We quantify the amount of planetesimals released during close stellar flybys, their ejection velocity and likely composition. We study the dependence of the effect of parabolic flybys on the mass ratio between the perturber and parent star, the periastron distance, inclination, and angle of periastron. Whenever ISOs are produced, they leave their parent system typically with velocities of 0.5-2 km/s. This ejection velocity is distinctly different to that of ISOs produced by planet scattering (4-8 km/s) and those shed during the stellar post-main-sequence phase 0.1-0.2 km/s). Using the typical disc truncation radius in various cluster environments, we find that clusters like the Orion nebula cluster are likely to produce the equivalent of 0.85 Earth-masses of ISOs per star. In contrast, clusters like NGC 3603 could produce up to 50 Earth-masses of ISOs per star. Our solar system probably produced the equivalent of 2-3 Earth masses of ISOs, which left our solar system at a mean ejection velocity of 0.7 km/s. Most ISOs produced by flybys should be comet-like, similar to Borisov. ISOs originating from compact long-lived clusters would often show a deficiency in CO. As soon as a statistically significant sample of ISOs is discovered, the combined information of their observed velocities and composition might help in constraining the dominant production process (abridged).Comment: 13 pages, 10 figures, accepted for A&

Boosting graduates' confidence in statistics

Recent research points to a lack of statistics knowledge in today’s graduate students

Discrete Choice Approach For Assessing Deprivation Cost In Humanitarian Relief Operations

One of the key objectives of humanitarian logistics is to guarantee the timely delivery of supplies to people affected by disasters during the response phase. In this regard, it is fundamental to design appropriate models to minimize the social costs of response operations to distribute essential supplies to populations in need. In addition to merely cover logistics cost, social costs include deprivations costs, which are an increasing function of deprivation time, derived from the human suffering caused by the lack of access to a good or a service. This research uses the theory of discrete choices to assess deprivation costs due to the time spent waiting for the delivery of a basket of basic supplies, defined as the changes in the welfare of people affected by disasters. To this end, we designed a stated choice survey, applied to people living in areas affected by floods and earthquakes in Colombia. The estimated models consider the influence of individual's socioeconomic characteristics and random effects on the deprivation cost functions. The functions have a nonlinear structure, strictly increasing, and convex on the deprivation time. The results are useful for estimating the social costs of humanitarian relief operations

Enhanced Production of 1,3‑Propanediol by Glycerol Fermentation Using an Attached‑to‑Silicone Bioflm Reactor

Glycerol fermentation for 1,3-propanediol (1,3-PDO) production was studied in an anaerobic up-flow reactor with biomass attached to silicone support. A mixed microbial culture was activated to perform the biofilm formation and attachment to a silicone hose prior the reactor operation. The reactor was operated over 362 days divided into two phases (P). In P1 and P2, the reactor was continuously fed with pure and crude glycerol, respectively. The operation consisted of increasing the glycerol loading rates (gly-LR). The achieved highest 1,3-PDO average yields were 0.43 mol mol-gly−1 and 0.62 mol mol-gly−1 when applied gly-LR was 18 and 46 g L−1 d−1 in P1 and P2, respectively. A maximum 1,3-PDO productivity of 14.7 g L−1 d−1 was obtained in P2. The higher yields of 1,3-PDO when the feed changed from pure to crude glycerol indicated a change in the microbial community. These results show that the studied system can be very promising and cost-effective for converting crude glycerol into value-added products on large scale even at high loadsThis study was funded by Spanish Ministry of Science and Innovation (Grant no: PID2019-104812GBI00X), UAM-Santander Inter-university Cooperation Projects with Latin America (CEAL-AL/2017-14), and CAPES-PrInt (fnance code 001, Process no 88887.467533/2019-00

Insuficiencia venosa crónica y los cambios estructurales en las paredes de las venas

Objectives: Among all the manifestations of the circulatory system of return, it is perhaps the chronic venous insufficiency that originates the most demand for consultation. This venous pathology that at first may occur imperceptibly, achieves within its development to generate conditions at the structural level in the venous wall that directly activate a series of symptoms that partially or totally incapacitate the sufferer. This is why the main objective of this review is to identify the best existing evidence on chronic venous insufficiency and structural changes in the vein wall. Method: bibliographical review, descriptive of longitudinal section and retrospective of the controlled scientific literature based on systematic reviews. Results: The evidence obtained confirmed that people between 60 and 69 years of age are the most prevalent in the development of CVI, representing 47% of the population studied. Followed by those who range between 70/79 years of age for 26% of the total sample of patients. On the other hand, in terms of sex, the studies evaluated show a higher incidence of CVI in females, representing 65% of the population studied. Regarding the risk factors for the development of the IVC, the studies showed that the non-modifiable ones have the highest incidence. It was possible to see among the authors coincidence with regard to the clinical manifestations that in one way or another regardless of which gave rise to the emergence of CVI, are the symptomatological picture prevailing in this venous pathology. Regarding the structural changes in the walls of the veins as a consequence of the IVC, the authors suggest that these modifications are characterized by the thickening and deformation of the vessel, with an increase in its permeability and loss of its antithrombotic properties. They also describe that in the histological study, endothelial cells with different degrees of alteration are revealed. From the increase of its organelles with the presence of large vesicles and vacuoles, degenerative myeloid bodies and developed cytoskeleton, to cells that have completely or partially detached from the venous wall. The subendothelial region shows great collagen infiltration. Conclusion: Among the risk factors predisposing to CVI, the studies reviewed include gender, age and family history. They also establish that the female sex is the most prone to the development of this venous pathology and people who are between 60 and 79 years of age. The most evident clinical symptomatology in the IVC is the sensation of heaviness, cramps, pruritus and evening edemas. With regard to the structural changes of the venous wall, the authors describe a thickening at the intimal level and in the middle layer, increase in collagen fibers, decrease in elastics and alteration of the morphology of smooth muscle cells that lose their characteristic orientation.Objetivos: Entre todas las manifestaciones del sistema circulatorio de retorno, es quizás, la insuficiencia venosa crónica la que origina más demanda de consulta. Esta patología venosa que al principio puede cursar de forma imperceptible, logra dentro de su desarrollo generar condiciones a nivel estructural en la pared venosa que logran de forma directa activar una serie de sintomatologías que logran incapacitar de forma parcial o total a quien la padece. Es por esto que el objetivo principal de la presente revisión es identificar la mejor evidencia existente sobre la insuficiencia venosa crónica y los cambios estructurales en la pared de las venas. Método: revisión bibliográfica, descriptiva de corte longitudinal y retrospectiva de la literatura científica controlada en base a revisiones sistemáticas. Resultados: La evidencia obtenida confirmo que las personas que se encuentran entre los 60 y los 69 años de edad, son los de mayor prevalencia en el desarrollo de la IVC representando el 47% de la población estudiada. Seguidos por los que oscilan entre los 70 / 79 años de edad para un 26% de la muestra total de pacientes. Por otro lado en cuanto al sexo, los estudios evaluados muestran una mayor incidencia de la IVC en el sexo femenino, representando 65% de la población estudiada. En cuanto a los factores de riesgo para el desarrollo de la IVC los estudios evidenciaron que los no modificables son los que poseen una mayor incidencia. Se pudo apreciar entre los autores coincidencia con lo que respecta a las manifestaciones clínicas que de una forma u otra sin importar que diera origen al surgimiento de la IVC, son el cuadro sintomatológico imperante en esta patología venosa. En lo que respecta a los cambios estructurales en las paredes de las venas a consecuencia de la IVC, los autores plantean que estas modificaciones se caracterizan por el engrosamiento y deformación del vaso, con aumento en su permeabilidad y pérdida de sus propiedades antitrombóticas. De igual forma describen que en el estudio histológico se revelan células endoteliales con diferentes grados de alteración. Desde aumento de sus organelos con presencia de grandes vesículas y vacuolas, cuerpos mieloides degenerativos y citoesqueleto desarrollado, hasta células que se han desprendido total o parcialmente de la pared venosa. La región subendotelial muestra gran infiltración colágena. Conclusión: Dentro de los factores de riesgos predisponentes de la IVC, los estudios revisados destacan el sexo, la edad y los antecedentes familiares. De igual forma establecen que el sexo femenino es el más propenso al desarrollo de esta patología venosa y las personas que se encuentran entre los 60 y 79 años de edad. Las  sintomatologías clínicas más evidentes en la IVC son la sensación de pesadez, calambres, prurito y edemas vespertinos. En lo que respecta a los cambios estructurales de la pared venosa, los autores describen un engrosamiento a nivel intimal y en la capa media, aumento de fibras colágenas, disminución de elásticas y alteración de la morfología de las células musculares lisas que pierden su orientación característica.&nbsp

Convolution Neural Network Models for Acute Leukemia Diagnosis

Acute leukemia is a cancer-related to a bone marrow abnormality. It is more common in children and young adults. This type of leukemia generates unusual cell growth in a short period, requiring a quick start of treatment. Acute Lymphoid Leukemia (ALL) and Acute Myeloid Leukemia (AML) are the main responsible for deaths caused by this cancer. The classification of these two leukemia types on blood slide images is a vital process of and automatic system that can assist doctors in the selection of appropriate treatment. This work presents a convolutional neural networks (CNNs) architecture capable of differentiating blood slides with ALL, AML and Healthy Blood Slides (HBS). The experiments were performed using 16 datasets with 2,415 images, and the accuracy of 97.18% and a precision of 97.23% were achieved. The proposed model results were compared with the results obtained by the state of the art methods, including also based on CNNs. (c) 2020 IEEE

MEDIAÇÃO E TRANSFORMAÇÃO SOCIAL

A mediação se tornou um ambiente privilegiado nos últimos tempos sem, contudo, ter conseguido amealhar, ao mesmo tempo, uma sofisticação teórica compatível com suas práticas que têm se tornado, cada vez mais, uma expressão do modelo neoliberal gerencial eficientista de gestão da crise do Sistema de Justiça. Na contramão disso, a literatura de Luis Alberto Warat nos permite pensar a mediação desde suas potencialidades disruptivas e transformadoras, dotada de uma potência que impacta as práticas jurídicas e seus atores. Este é o foco deste texto, recuperando alguns conceitos construídos por este autor

Follow-up of the air pollution and the human male-to-female ratio analysis in São Paulo, Brazil: a times series study

Objectives in order to assess if ambient air pollution in urban areas could be related to alterations in male/female ratio this study objectives to evaluate changes in ambient particulate matter (PM10) concentrations after implementation of pollution control programmes in São Paulo city and the secondary sex ratio (SRR).Design and methods A time series study was conducted. São Paulo's districts were stratified according to the PM10 concentrations levels and were used as a marker of overall air pollution. the male ratio was chosen to represent the secondary sex ratio (SSR=total male birth/total births). the SSR data from each area was analysed according to the time variation and PM10 concentration areas using descriptive statistics. the strength association between annual average of PM10 concentration and SSR was performed through exponential regression, and it was adopted as a statistical significance level of p<0.05.Results the exponential regression showed a negative and significant association between PM10 and SSR. SSR varied from 51.4% to 50.7% in São Paulo in the analysed period (2000-2007). Considering the PM10 average concentration in São Paulo city of 44.72g/m(3) in the study period, the SSR decline reached almost 4.37%, equivalent to 30934 less male births.Conclusions Ambient levels of PM10 are negatively associated with changes in the SSR. Therefore, we can speculate that higher levels of particulate pollution could be related to increased rates of female births.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Universidade Federal de São Paulo UNIFESP, ICAQF, Dept Ciencias Exatas & Terra, São Paulo, BrazilUniv São Paulo, Sch Med, Dept Pathol, Lab Expt Air Pollut LIM05, São Paulo, BrazilUniversidade Federal de São Paulo UNIFESP, ICAQF, Dept Ciencias Exatas & Terra, São Paulo, BrazilCNPq: 573813/2008-5: FAPESP - 2008/57717-6Web of Scienc

Construction and demolition waste recycling through conventional jig, air jig, and sensor-based sorting a comparison

The paper presents a comparison of the concentration methods conventional jig, air jig, and sensor-based sorting to treat construction and demolition waste. All tests were made with concrete, brick, and gypsum particles and the tests aim to separate these materials into different size ranges, depending on the method. The equipment tested, conventional jig, air jig, and sensor-based sorting present good results to concentrate construction and demolition waste particles, with different concentrations and mass recoveries. The results show particularly good mass recoveries and particle concentration for conventional jig, especially for concrete and gypsum particles. Sensor-based sorting should preferably use concentration circuits for best results

AVALIAÇÃO DE TÉCNICAS DE SEGMENTAÇÃO PARA LEUCÓCITOS EM IMAGENS DE SANGUE

A leucemia é um tipo de câncer que se origina na medula óssea e é caracterizado pela proliferação anormal de leucócitos no sangue. Para que ocorra a identificação correta dos linfoblastos, os especialistas examinam cada lâmina de sangue do paciente. Este método é influenciado por fatores como a experiência do hematologista e uma grande quantidade de trabalho por analisar imagem por imagem, isso pode resultar em relatórios não padronizados e até erros. Uma solução de baixo custo e eficiente é a utilização de sistema que examine as imagens microscópicas de sangue. Concluiu-se a partir da revisão literária que o processo de automação desse sistema depende de uma segmentação adequada. Neste trabalho, comparamos 9 métodos de segmentação em três bases de imagens públicas com o objetivo de verificar os erros nos métodos a fim de determinar qual deles apresenta os melhores resultados