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This study tackles the growing global concern about municipal waste management, particularly in cities like the Grand Guayaquil Metropolitan Area (GGA). Through realistic field studies on in situ household waste generation and geographic information system (GIS) tools, this work offers a framework to predict the quantities and types of recyclable household waste for any metropolitan area in Latin America. Over 4 weeks, students collected, sorted and weighed recyclable waste types, including plastic, paper, metal, glass and fabric, from 776 sampled household of the GGA. ArcGIS survey tool identified household locations and allowed to survey different socio-demographic features. With the help of ArcGIS interpolation method, the total household waste generation for GGA was predicted, and the classification of the different types of recyclable waste was also spatially distributed for the study area. The report identified notable trends in plastic waste, specifically polyethylene terephthalate waste's steady prevalence and 42% growth rate, emphasizing the importance of enhanced recycling techniques. Spatial density maps showed a heterogeneous waste distribution across the GGA, emphasizing locations with higher waste output. This study demonstrates that improving recyclable waste collection can be accomplished with a moderately cheap expenditure by collaborating with academia to overcome knowledge gaps. This strategy provides opportunities to mitigate the environmental impacts of poor waste management.
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Cidades , Reciclagem , Gerenciamento de Resíduos , Gerenciamento de Resíduos/métodos , Sistemas de Informação Geográfica , Características da Família , Plásticos , Resíduos Sólidos/análise , Eliminação de Resíduos/métodos , Eliminação de Resíduos/estatística & dados numéricos , Resíduos/estatística & dados numéricos , América LatinaRESUMO
INTRODUCTION: The surgical education has evolved by adopting the visual platforms as a resource of searching. The videos complement the visual learning of surgical techniques of trainees, residents, and surgeons. YouTube® is the most frequently consulted platform in the surgical field. WebSurg® and GIBLIB® are two recognized medical platforms. The Critical View of Safety (CVS) is the most important and effective method to reduce the risk of bile duct injury (BDI) in laparoscopic cholecystectomy (LC). Reaching a satisfactory CVS is a crucial point. We evaluated the CVS of videos on WebSurg® and GIBLIB®, comparing the results with those of the worldwide most popular video platform. METHODS: We performed a search under the term "Laparoscopic cholecystectomy" on the virtual platforms YouTube®, GIBLIB®, and WebSurg®. Three evaluators reviewed the 77 selected videos using the "Sanford-Strasberg' CVS score." The inferential analysis was performed between two groups: YouTube® and Non-YouTube (GIBLIB® and WebSurg®). The characteristics of each video were analyzed including country of origin, type of profile, number of views, and number of Likes. RESULTS: Satisfactory CVS obtained from each of the platforms was GIBLIB® 40%; WebSurg® 44.4%; YouTube® 27.7%. The comparative analysis of CVS quality and CVS score for the Non-YouTube and YouTube® groups did not show a significant difference (p = 0.142, p = 0.377, respectively). CONCLUSION: The videos on GIBLIB® and WebSurg® offer a higher probability of satisfactory CVS compared to YouTube®. Nevertheless, there is no significant superiority of GIBLIB® and WebSurg® over YouTube®.
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Colecistectomia Laparoscópica , Mídias Sociais , Colecistectomia Laparoscópica/métodos , Humanos , Gravação em Vídeo/métodosRESUMO
Seaweed aquaculture is affected by natural and anthropogenic stressors, which put the biomass productivity of the cultures at risk. Seaweed biomass for commercial purposes, principally in pharmaceutical and/or nutraceutical applications, needs to be free of pollutants; therefore, controlled cultures have relevance in regulating the quality of biomass. The aim of this work was to demonstrate the successful utilization of controlled outdoor cultures to remove excess heavy metal accumulation in Gracilaria chilensis, an important commercial seaweed farming model. Specifically, we designed a simple and operational heavy metal depuration protocol, utilizing seawater and tap water removal, which permitted the concentration reduction of 10 heavy metals, including As, Cu, and Cd but not Zn, from the biomass at 7 days of culture. The percentage of depuration of the heavy metals ranged from 32 to 92% at 7 days, which was maintained throughout 21 days of culture. During the culture period, the monitored physicochemical parameters (temperature, salinity, and dissolved oxygen, among others) remained stable, with an increase in the daily growth rate (DGR% d-1) of the biomass recorded after 14 days of culture. Consequently, the experimental setup was successful for heavy metal depuration, which highlights the importance of controlled outdoor cultures as important tools of sustainability.
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Poluentes Ambientais , Gracilaria , Metais Pesados , Rodófitas , Alga Marinha , Poluentes Químicos da Água , Cádmio , Água , Oxigênio , Preparações Farmacêuticas , Poluentes Químicos da Água/análiseRESUMO
This first region-wide study (N = 2,818) aims to estimate prevalence of HIV-related risks (sexual behavior, HIV disclosure, number of sex partners, violence) and factors associated with these risks as well as evaluate a behavior change communications program targeted to PLHIV in 6 countries in Central America. After 2 years, the program achieved moderate coverage, with 21 % of the sample reporting exposure to interpersonal communications (IPC) and 52 % to mass media program components. The odds of condom use, HIV disclosure, and participation in a self-help group increased by 1.4-1.8 times with exposure to mass media. Exposure to IPC increased odds of condom use by 2.7 and participation in self-help groups by 4.4 times. In addition, being in HIV care or taking ART was associated with condom use and HIV-status disclosure. About 30 % experienced physical or sexual violence, and those who did were 4 times less likely to use condoms. Findings suggest that behavioral interventions for PLHIV can reduce HIV-transmission risks and increase access to care.
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Comunicação , Preservativos/estatística & dados numéricos , Infecções por HIV/prevenção & controle , Comportamento de Redução do Risco , Comportamento Sexual , Adolescente , Adulto , América Central , Estudos Transversais , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Avaliação de Programas e Projetos de Saúde , Assunção de Riscos , Sexo Seguro/estatística & dados numéricos , Grupos de Autoajuda , Parceiros Sexuais , Inquéritos e Questionários , Revelação da VerdadeRESUMO
BACKGROUND: Despite over a decade of research and programming, little evidence is available on effective strategies to reduce HIV risks among Central American men who have sex with men (MSM). The Pan-American Social Marketing Organization (PASMO) and partners are implementing a HIV Combination Prevention Program to provide key populations with an essential package of prevention interventions and services: 1) behavioral, including interpersonal communications, and online outreach; 2) biomedical services including HIV testing and counseling and screening for STIs; and 3) complementary support, including legal support and treatment for substance abuse. Two years into implementation, we evaluated this program's effectiveness for MSM by testing whether exposure to any or a combination of program components could reduce HIV risks. METHODS: PASMO surveyed MSM in 10 cities across Guatemala, El Salvador, Nicaragua, Costa Rica, and Panama in 2012 using respondent-driven sampling. We used coarsened exact matching to create statistically equivalent groups of men exposed and non-exposed to the program, matching on education, measures of social interaction, and exposure to other HIV prevention programs. We estimated average treatment effects of each component and all combined to assess HIV testing and condom use outcomes, using multivariable logistic regression. We also linked survey data to routine service data to assess program coverage. RESULTS: Exposure to any program component was 32% in the study area (n = 3531). Only 2.8% of men received all components. Men exposed to both behavioral and biomedical components were more likely to use condoms and lubricant at last sex (AOR 3.05, 95% CI 1.08, 8.64), and those exposed to behavioral interventions were more likely to have tested for HIV in the past year (AOR 1.76, 95% CI 1.01, 3.10). CONCLUSIONS: PASMO's strategies to reach MSM with HIV prevention programming are still achieving low levels of population coverage, and few men are receiving the complete essential package. However, those reached are able to practice HIV prevention. Combination prevention is a promising approach in Central America, requiring expansion in coverage and intensity.
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Infecções por HIV/prevenção & controle , Homossexualidade Masculina/estatística & dados numéricos , Cooperação do Paciente/estatística & dados numéricos , Prevenção Primária/organização & administração , Sexo Seguro/estatística & dados numéricos , Adolescente , Adulto , América Central/epidemiologia , Preservativos/estatística & dados numéricos , Costa Rica/epidemiologia , El Salvador/epidemiologia , Guatemala/epidemiologia , Infecções por HIV/epidemiologia , Humanos , Modelos Logísticos , Masculino , Programas de Rastreamento/estatística & dados numéricos , Nicarágua/epidemiologia , Avaliação de Programas e Projetos de Saúde , Comportamento de Redução do Risco , Parceiros Sexuais/classificação , Inquéritos e QuestionáriosRESUMO
Additive Manufacturing (AM) has recently demonstrated significant medical progress. Due to advancements in materials and methodologies, various processes have been developed to cater to the medical sector's requirements, including bioprinting and 4D, 5D, and 6D printing. However, only a few studies have captured these emerging trends and their medical applications. Therefore, this overview presents an analysis of the advancements and achievements obtained in AM for the medical industry, focusing on the principal trends identified in the annual report of AM3DP.
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Amyand's hernia is defined as the presence of the appendix within an inguinal hernia sac, which is often associated with appendicitis. The association of an Amyand's hernia with an appendicular tumor has been reported in very few cases. This case report presents a 67-year-old female patient who came to the emergency department with symptoms indicative of a complicated inguinal hernia. Following surgical treatment, the diagnosis of Amyand's hernia with cecal perforation associated with an appendicular tumor was established in the context of a previous laparoscopic femoral hernia repair. The combination of these conditions has not been previously reported. The presentation of this case provides data on the clinical presentation, diagnosis, and treatment of this rare pathology that requires a high clinical suspicion to achieve a preoperative diagnosis.
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With the growing recognition of coupled human and natural systems (CHANS), modeling CHANS with two-way feedbacks has become a frontier research area and a critical tool to achieve sustainability. The challenges in CHANS modeling and opportunities to advance its science and application to promote the sustainability of CHANS are discussed in this paper.
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Taking into consideration climate change scenarios, marine contamination, and a constantly expanding world population, seaweed aquaculture has become an important option for the large-scale production of high-quality biomass. Due to existing biological knowledge of Gracilaria chilensis, several cultivation strategies have been established for obtaining diverse biomolecules (lipids, fatty acids, pigments, among others) with nutraceutical properties. In this research, indoor and outdoor cultivation methodologies were applied to generate high biomass of G. chilensis with positive quality for productive purposes, where the quality was determined according to the concentrations of lipoperoxides and phenolic compounds and the total antioxidant capacity (TAC). The results showed that G. chilensis cultures, which were fertilized for three weeks with Basfoliar® Aktiv (BF) at concentrations of 0.05-1% v/v, obtained high biomass (1-1.3 kg m-2) and DGR (0.35-4.66% d-1), low lipoperoxides (0.5-2.8 µmol g-1 DT), and high phenolic compounds (0.4-0.92 µ eq. GA g-1 FT) and TAC (5-7.5 nmol eq. TROLOX g-1 FT) as compared with other culture media. Lower stress was determined under indoor cultures, due to the operative control of diverse physicochemical stressor parameters (T°, light intensity, photoperiod, among others). Therefore, the cultures developed allow scaling the biomass in productive terms and are suitable for obtaining compounds of interest.
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Three new species of oil-collecting bees of the genus Centris (Xanthemisia) Moure are described and illustrated: C. jakalteka sp. nov., C. maya sp. nov. and C. purhepecha sp. nov. The new proposed taxa are distributed in the north of the Neotropical Region, specifically in the Mesoamerican Dominion and the Mexican Transition Zone, between the Neotropics and Nearctic. In addition, a distribution map and an identification key for the species of the subgenus occurring in the aforementioned regions are also presented.
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Himenópteros , Abelhas , Animais , Distribuição Animal , MéxicoRESUMO
Heavy metals and polycyclic aromatic hydrocarbons (PAHs) are ubiquitous contaminants that frequently co-occur in coastal environments. These contaminants can have negative impacts on the health and stability of marine and coastal ecosystems, affecting both the organisms themselves and the humans who consume them. A coastal industrial park in central Chile, housing a coal thermal power plant and other industrial activities, contributes to such pollution of coastal waters; however, neither the spatial alongshore distribution of heavy metals and PAHs, nor an assessment of their ecological effects on the biota have been systematically documented to date. In this paper, we present evidence regarding the direct negative effect of contamination by heavy metals and PAHs on the early life stages of kelps-being extremely harmful to their population persistence near highly polluted sites-as well as the indirect effects of their transference through the food web to higher trophic levels, leading to negative consequences for the feeding intake, growth, fertility, and larval development of marine herbivores that consume the contaminated seaweed. Likewise, the dispersion of contaminants by ocean currents can exacerbate the effects of pollution, having an adverse influence on marine ecosystem health even at sites far from the pollution source. Therefore, it is necessary to investigate the distribution patterns and extent of pollution along the coast to understand the impact of heavy metals and PAHs pollution on seaweed populations and the food web. It is considered critical for the development of effective environmental policies and regulations to protect these ecosystems and the people who depend on them.
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Kelp , Metais Pesados , Hidrocarbonetos Policíclicos Aromáticos , Alga Marinha , Poluentes Químicos da Água , Humanos , Ecossistema , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Herbivoria , Metais Pesados/toxicidade , Metais Pesados/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/análise , Sedimentos GeológicosRESUMO
INTRODUCTION: Maximal inspiratory and expiratory pressures (PImax/PEmax) reference equations obtained in healthy people are needed to correctly interpret respiratory muscle strength. Currently, no clear cut-off points defining respiratory muscle weakness are available. We aimed to establish sex-specific reference equations for PImax/PEmax in a large sample of healthy adults and to objectively determine cut-off points for respiratory muscle weakness. METHODS: A multicentre cross-sectional study was conducted across 14 Spanish centres. Healthy non-smoking volunteers aged 18-80 years stratified by sex and age were recruited. PImax/PEmax were assessed using uniform methodology according to international standards. Multiple linear regressions were used to obtain reference equations. Cut-off points for respiratory muscle weakness were established by using T-scores. RESULTS: The final sample consisted of 610 subjects (314 females; 48 [standard deviation, SD: 17] years). Reference equations for PImax/PEmax included body mass index and a squared term of the age as independent variables for both sexes (p<0.01). Cut-off points for respiratory muscle weakness based on T-scores ≥2.5 SD below the peak mean value achieved at a young age were: 62 and 83cmH2O for PImax and 81 and 109cmH2O for PEmax in females and males, respectively. CONCLUSION: These reference values, based on the largest dataset collected in a European population to date using uniform methodology, help identify cut-off points for respiratory muscle weakness in females and males. These data will help to better identify the presence of respiratory muscle weakness and to determine indications for interventions to improve respiratory muscle function.
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Pressões Respiratórias Máximas , Insuficiência Respiratória , Masculino , Feminino , Humanos , Adulto , Estudos Transversais , Força Muscular/fisiologia , Músculos Respiratórios/fisiologiaRESUMO
Background: Xicotli data is the short name given to the dataset generated within the project framework "Integration of Biodiversity Data for the Management and Conservation of Wild Bee-Plant Interactions in Mexico (2021-2023)", as xicotli is the generic word for a bee in Nahuatl. The team comprised eco-informaticians, ecologists and taxonomists of both native bees and flora. The generated dataset contains so far 4,532 curated records of the plants, which are potential hosts of species of three focal families of bees native to Mexico: Apidae, Halictidae and Megachilidae and morphological and ecological data of the plant-bee interactions. This dataset was integrated and mobilised from citizen observations available at naturalista.mx (iNat), which were compiled through the iNaturalist project. New information: The new information obtained with the Xicotli data project was: Taxonomic information about bee species curated by taxonomists based on the information contained in iNaturalist;Taxonomic identification of the host plants by a botanist from the photos compiled by the Xicotli Data project;Data on the ecomorphological traits of bees and plants based on expert knowledge and literature. All the data were integrated into the Xicotli Data Project via the creation of new "observation fields". The visibility of the information originally contained in iNaturalist was maximized and can be consulted directly on the iNaturalist platform.
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We present a review of the genus Xylocopa (Neoxylocopa) of Mexico and Mesoamerica in which 11 species are recognized, including: X. clarionenis, X. fimbriata, X. frontalis, X. gualanensis, X. mexicanorum, X. nautlana, X. ocellaris, X. sonorina, X. wilmattae. Additionally, two new species are described, X. griswoldi sp. nov. with distribution in the United States and Mexico, and X. maya sp. nov. present in Mexico and Belize. Three species groups within the subgenus Neoxylocopa are recognized: frontalis, mexicanorum and sonorina. Identification keys are presented for identifying species groups and species. Furthermore, images of species and morphological structures as well as information regarding distribution are provided.
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Himenópteros , Animais , Abelhas , Cabeça , MéxicoRESUMO
PAHs and heavy metals are characteristic pollutants in urbanized coastal areas, especially those with industrial activity. Given this context and the ability of Macrocystis pyrifera to drift when detached and provide trophic subsidy in coastal systems, we analyzed the potential transfer of pollutants to the herbivore Tetrapygus niger, through diet, in an industrialized coastal zone in Central Chile (Caleta Horcón) and characterized the impacted zone using diverse polluted ecotoxicological indices. For this purpose, a culture experiment was conducted where M. pyrifera individuals from Algarrobo (control site) were cultivated in Caleta Horcón and then used as food for T. niger. The contents of both PAHs and heavy metal contents were subsequently determined in algal tissue and sea urchin gonads as well as in the seawater. The results show that algae cultivated in Caleta Horcón had higher concentrations of naphthalene (NAF) compared to those from a low industrial impact zone (Algarrobo) (2.5 and 1.8 mg kg-1, respectively). The concentrations of Cu, As, and Cd were higher in Caleta Horcón than in Algarrobo in both M. pyrifera and T. niger. For all metals, including Pb, higher concentrations were present in T. niger than in M. pyrifera (between 5 and 798 times higher). Additionally, as indicated by the toxicological indices MPI (0.00804) and PLI (10.89), Caleta Horcón is highly contaminated with metals compared to Algarrobo (0.0006 and 0.015, respectively). Finally, the bioconcentration factor (BCF) and trophic transfer factor (TTF) values were greater than one in most cases, with values in Caleta Horcón exceeding those in Algarrobo by one or two orders of magnitude. This study provides evidence that Caleta Horcón is a highly impacted zone (HIZ) compared to Algarrobo, in addition to evidence that the biomagnification of certain pollutants, including the possible responses to contaminants, are apparently not exclusively transferred to T. niger through diet.
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T-cell receptor (TCR)-based adoptive therapy employs genetically modified lymphocytes that are directed against specific tumor markers. This therapeutic modality requires a structured and integrated process that involves patient screening (e.g., for HLA-A*02:01 and specific tumor targets), leukapheresis, generation of transduced TCR product, lymphodepletion, and infusion of the TCR-based adoptive therapy. In this review, we summarize the current technology and early clinical development of TCR-based therapy in patients with solid tumors. The challenges of TCR-based therapy include those associated with TCR product manufacturing, patient selection, and preparation with lymphodepletion. Overcoming these challenges, and those posed by the immunosuppressive microenvironment, as well as developing next-generation strategies is essential to improving the efficacy and safety of TCR-based therapies. Optimization of technology to generate TCR product, treatment administration, and patient monitoring for adverse events is needed. The implementation of novel TCR strategies will require expansion of the TCR approach to patients with HLA haplotypes beyond HLA-A*02:01 and the discovery of novel tumor markers that are expressed in more patients and tumor types. Ongoing clinical trials will determine the ultimate role of TCR-based therapy in patients with solid tumors.
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Imunoterapia Adotiva/métodos , Neoplasias/terapia , Animais , Humanos , Neoplasias/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T/imunologia , Microambiente TumoralRESUMO
The study of pollution effects in the marine environment has become important in recent decades, and the exposure to simultaneous pollutants has become especially relevant. Indeed, the study of key organisms, such as ecosystem engineers, can show a broader view of the effects of pollutants. In this context, we evaluate in situ the effects of a short (7-day) pollution pulse of combined solutions of heavy metals and polycyclic aromatic hydrocarbons (PAHs) (Cu + PAHs, Cd + PAHs, Cu + Cd, and Cu + Cd + PAHs) on the development and morphological features of Macrocystis pyrifera sporophytes over a period of 90 days. Additionally, we determined the effects on the community structure associated with this kelp. This study evidenced a smaller number of blades and a decreased size of blades and holdfasts, as well as the death of individuals exposed to a secondary mix of metals (Cu + Cd) and a tertiary mix of pollutants (Cu + Cd + PAHs). Regarding the effects on the accompanying fauna, low richness and diversity were registered. M. pyrifera grazers, according to the mixture of pollutants, were either absent or diminished. These results show that the pulse of contamination in the early stages of M. pyrifera negatively affects its development and morphometry, as well as its role as an ecosystem engineer, due to a negative alteration in the species composition.
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The industrial park of Quintero Bay (QB) in the central coast of Chile was established in the 1960s, presents high levels of pollution due to the industrial activity, and it is known as one of the five Chilean "sacrifice zones". Lessonia spicata is the most important habitat-forming kelp species in the intertidal along the central and south shores of Chile, and currently there are no morphometric and population studies of L. spicata (or other seaweed species) nor studies about the effects of pollution on its development in QB and neighbouring sites. In this context, the aims of this study were (i) to register the abundance and morphological features of L. spicata populations from Ventanas, Horcón and Cachagua (sites with different pollution histories and located only up to 40 km from the QB); ii) to determine the heavy metals (HMs) concentration in seawater and marine sediments; and (iii) to evaluate in vitro the effects of exposure to seawater from the three sampling sites on spore release and early developmental stages, up to the juvenile sporophyte. Results showed that the chronically exposed Ventanas kelp population had the smallest adult individuals in comparison with the other sites. Ventanas and Horcón registered high HMs concentration in the seawater and marine sediments exceeding the international permissible limits (e.g in seawater Cu 20-859 µg L-1; sediments Cu > 50,000 µg kg-1). Unexpectedly in Cachagua, a site often considered unpolluted, high concentrations of Cu and As were also registered in the seawater (859 and 1,484 µg L-1, respectively) and of As in marine sediments (20,895 µg kg-1). Exposure of gametophytes to the seawater from Ventanas resulted in a developmental delay compared to the other treatments; however, low sporophyte production was determined in all treatments. Our results indicate that QB, more notably Ventanas, induce highly negative effects on individual development, and consequently on seaweed populations, which suggest a long-term negative impact on the community structure of these marine zones. Furthermore, the high concentrations of HMs reported here at Cachagua suggest a recent expansion of pollution along the central coast of Chile, evidencing effects on the marine ecosystem health even on sites far from the pollution source.
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Kelp/efeitos dos fármacos , Instalações Industriais e de Manufatura , Dispersão Vegetal/efeitos dos fármacos , Água do Mar/química , Poluentes Químicos da Água/efeitos adversos , Baías , Chile , Monitoramento Ambiental/estatística & dados numéricos , Kelp/crescimento & desenvolvimentoRESUMO
Las neoplasias del apéndice son un grupo heterogéneo de tumores con una incidencia baja, la presentación clínica es inespecífica, cursando generalmente de forma asintomática, y la tomografía es el estudio de elección para el diagnóstico. El tratamiento dependerá del tipo histológico del tumor.The appendix neoplasms are a heterogeneous group of tumors with a low incidence, the clinical presentation is nonspecific, usually being asymptomatic, tomography is the study of choice for the diagnosis. Treatment will depend on the histological type of the tumor.
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Apêndice , Neoplasias , Apêndice/diagnóstico por imagem , Apêndice/cirurgia , Hospitais , Humanos , IncidênciaRESUMO
In this work, we develop a model able to predict the equilibrium separation of gases due to differences in their molecular weights and the action of gravity. The separation of H, He, O, and N2 with altitude is a characteristic phenomenon of the heterosphere. The model is able to qualitatively recreate the compositional profile of the whole heterosphere from a single composition measurement. The model is applied to the separation of air components and pollutants by empty wells drilled on the planet surface. It predicts that the separation of gases would be possible in wells deep enough under equilibrium. The high molecular weight of some anthropogenic pollutants (SO2, O3, NO2, CO2, etc.) would facilitate their segregation along shorter distances compared to those involved in the heterosphere. The simulations indicate that deep wells could concentrate some air components and pollutants by orders of magnitude over the levels at the Earth's surface without external energy input. For instance, argon molar fractions of >40% and >60% could be achievable at 44â¯km and 55â¯km depth, respectively. Finally, we discuss the feasibility of gravitational separation as a potential pollution abatement technology.