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1.
Brain Sci ; 14(5)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38790404

RESUMO

Lucid dreaming (LD) is a physiological state of consciousness that occurs when dreamers become aware that they are dreaming, and may also control the oneiric content. In the general population, LD is spontaneously rare; thus, there is great interest in its induction. Here, we aim to review the literature on neuropsychopharmacological induction of LD. First, we describe the circadian and homeostatic processes of sleep regulation and the mechanisms that control REM sleep with a focus on neurotransmission systems. We then discuss the neurophysiology and phenomenology of LD to understand the main cortical oscillations and brain areas involved in the emergence of lucidity during REM sleep. Finally, we review possible exogenous substances-including natural plants and artificial drugs-that increase metacognition, REM sleep, and/or dream recall, thus with the potential to induce LD. We found that the main candidates are substances that increase cholinergic and/or dopaminergic transmission, such as galantamine. However, the main limitation of this technique is the complexity of these neurotransmitter systems, which challenges interpreting results in a simple way. We conclude that, despite these promising substances, more research is necessary to find a reliable way to pharmacologically induce LD.

2.
Diagn Cytopathol ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38808690

RESUMO

BACKGROUND: Ocular cytology is an effective method of diagnosing infective, benign, and malignant ocular disease processes due to easy accessibility and rapid turnaround time. However, these specimens pose significant diagnostic challenges due to rarity of the specimen type, sparse diagnostic material available for ancillary workup, and unfamiliarity of the diagnostic entities by the cytopathologist. METHODS: This study conducted a 6-year comprehensive review of 65 eye cytology cases received at a tertiary level hospital. Cytopathologic diagnoses of "negative for malignancy" and "atypical" were categorized as negative findings (70.8%, n = 46) and diagnoses of "suspicious for malignancy" and "positive for malignancy" were categorized as positive findings (23.1%, n = 15). A 44.6% (n = 29) of cases had subsequent histopathology and/or flow cytometry diagnoses. Premalignant and malignant lesions detected on histopathology were considered as significant findings. Statistical analysis was performed to evaluate the concordance of ocular cytology with associated histopathology and/or flow cytometry diagnoses. RESULTS: The accuracy of final cytology-histopathology and/or cytology-flow cytometry diagnoses in this cohort of cases is 86.2%. The sensitivity and specificity of ocular diagnosis by cytology are 66.6% and 100%, respectively. The positive and negative predictive values of ocular diagnosis by cytology are 100% and 80.9%, respectively. CONCLUSION: Ocular cytology is a fast, effective, and sensitive method for diagnosing ocular pathology specimens. Familiarity with these specimen types by cytopathologists can help in diagnosing ocular diseases effectively on small, challenging cytologic preparations.

3.
Diagn Cytopathol ; 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38666389

RESUMO

INTRODUCTION: Dual immunostaining for p16/Ki67 is FDA-approved for use on liquid-based cervical cytology specimens; however, the utility of dual staining in anal cytology especially for ASCUS risk stratification is not well established. METHODS: We investigated dual staining performance on anal cytology specimens and correlated with subsequent cytologic interpretation, high-risk HPV status, and anal biopsy results. Dual staining for p16/Ki-67 was performed on all liquid-based anal cytology specimens from December 2021 to June 2022 (n = 43). RESULTS: Three patients had high grade squamous intraepithelial lesion (HSIL/AIN2-3) on biopsy; dual staining was positive in all three cases. All HR-HPV negative cases were negative for dual staining. Among the 12 ASCUS samples with subsequent anal biopsy results all also had HR-HPV testing. Due to small sample size of cases with squamous intraepithelial lesion (SIL) diagnosed on biopsy, the sensitivity and positive predictive value was not calculated. However, the specificity and negative predictive value of p16/Ki-67 dual staining for SIL of any grade on biopsy were 1 (95% CI: 0.66-1) and 0.9 (95% CI: 0.65-0.97) respectively, whereas the specificity and negative predictive value of HR-HPV testing for SIL of any grade on biopsy were 0.44 (95% CI: 0.14-0.79) and 0.8 (95% CI: 0.41-0.96) respectively. CONCLUSION: Dual p16/Ki-67 staining indicates transforming HPV infection and could help serve as an ancillary test for risk stratification for atypical anal cytology specimens. Among ASCUS samples, dual staining was specific for SIL of any grade with a high negative predictive value and therefore could be useful in clinical practices with limited availability for follow-up care.

4.
Arch Cardiol Mex ; 94(Supl 1): 1-74, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38648647

RESUMO

Chronic heart failure continues to be one of the main causes of impairment in the functioning and quality of life of people who suffer from it, as well as one of the main causes of mortality in our country and around the world. Mexico has a high prevalence of risk factors for developing heart failure, such as high blood pressure, diabetes, and obesity, which makes it essential to have an evidence-based document that provides recommendations to health professionals involved in the diagnosis and treatment of these patients. This document establishes the clinical practice guide (CPG) prepared at the initiative of the Mexican Society of Cardiology (SMC) in collaboration with the Iberic American Agency for the Development and Evaluation of Health Technologies, with the purpose of establishing recommendations based on the best available evidence and agreed upon by an interdisciplinary group of experts. This document complies with international quality standards, such as those described by the US Institute of Medicine (IOM), the National Institute of Clinical Excellence (NICE), the Intercollegiate Network for Scottish Guideline Development (SIGN) and the Guidelines International Network (G-I-N). The Guideline Development Group was integrated in a multi-collaborative and interdisciplinary manner with the support of methodologists with experience in systematic literature reviews and the development of CPG. A modified Delphi panel methodology was developed and conducted to achieve an adequate level of consensus in each of the recommendations contained in this CPG. We hope that this document contributes to better clinical decision making and becomes a reference point for clinicians who manage patients with chronic heart failure in all their clinical stages and in this way, we improve the quality of clinical care, improve their quality of life and reducing its complications.


La insuficiencia cardiaca crónica sigue siendo unas de las principales causas de afectación en el funcionamiento y en la calidad de vida de las personas que la presentan, así como una de las primeras causas de mortalidad en nuestro país y en todo el mundo. México tiene una alta prevalencia de factores de riesgo para desarrollar insuficiencia cardiaca, tales como hipertensión arterial, diabetes y obesidad, lo que hace imprescindible contar con un documento basado en la evidencia que brinde recomendaciones a los profesionales de la salud involucrados en el diagnóstico y el tratamiento de estos pacientes. Este documento establece la guía de práctica clínica (GPC) elaborada por iniciativa de la Sociedad Mexicana de Cardiología (SMC) en colaboración con la Agencia Iberoamericana de Desarrollo y Evaluación de Tecnologías en Salud, con la finalidad de establecer recomendaciones basadas en la mejor evidencia disponible y consensuadas por un grupo interdisciplinario y multicolaborativo de expertos. Cumple con estándares internacionales de calidad, como los descritos por el Institute of Medicine de los Estados Unidos de América (IOM), el National Institute of Clinical Excellence (NICE) del Reino Unido, la Intercollegiate Network for Scottish Guideline Development (SIGN) de Escocia y la Guidelines International Network (G-I-N). El grupo de desarrollo de la guía se integró de manera interdisciplinaria con el apoyo de metodólogos con experiencia en revisiones sistemáticas de la literatura y en el desarrollo de GPC. Se llevó a cabo y se condujo metodología de panel Delphi modificado para lograr un nivel de consenso adecuado en cada una de las recomendaciones contenidas en esta GPC. Esperamos que este documento contribuya para la mejor toma de decisiones clínicas y se convierta en un punto de referencia para los clínicos que manejan pacientes con insuficiencia cardiaca crónica en todas sus etapas clínicas, y de esta manera logremos mejorar la calidad en la atención clínica, aumentar la calidad de vida de los pacientes y disminuir las complicaciones de la enfermedad.


Assuntos
Insuficiência Cardíaca , Humanos , Insuficiência Cardíaca/terapia , Insuficiência Cardíaca/diagnóstico , Doença Crônica , México
5.
Zootaxa ; 5411(1): 1-71, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38480220

RESUMO

This paper presents a taxonomic revision of the genus Tullgrenella Mello-Leito, 1941. Four new species are described: Tullgrenella aisenbergae Marta, sp. nov. (Brazil) (), T. legalissima Marta & Hagopin sp. nov. (Uruguay) (), T. galianoae Marta, sp. nov. (Brazil) () and T. sciosciae Marta & Bustamante sp. nov. (Brazil) (). The males of T. corrugata Galiano, 1981 and T. peniaflorensis Galiano, 1970, and the female of T. selenita Galiano, 1970 are described for the first time. An updated diagnosis for the genus is provided based on the detailed comparative morphological studies. In addition, we present a proposal and discussion about the species groups of Tullgrenella based on the putative synapomorphies as well as the updated distribution of the genus in South America.


Assuntos
Aranhas , Masculino , Feminino , Animais , Distribuição Animal
6.
Rev Med Interne ; 45(3): 147-155, 2024 Mar.
Artigo em Francês | MEDLINE | ID: mdl-38388303

RESUMO

Gastrointestinal involvement in systemic sclerosis can be severe, reaching the critical point of chronic intestinal pseudo-obstruction, secondary to major disorders of small bowel motility. It is associated with some clinical and biological characteristics, in particular the positivity of anti-fibrillarin/U3RNP antibodies. Chronic intestinal pseudo-obstruction (CIPO) is complicated by a small intestinal bacterial overgrowth that requires cyclic antibiotic therapy. CIPO leads to a reduction of the food intake, due to painful symptoms, nausea and vomiting caused by meals, and ultimately to severe malnutrition. Meal splitting is often transiently effective and patients require exogenous nutritional support, mostly parenteral. Systemic sclerosis is not an obstacle to initiation and long-term continuation of parenteral nutrition and central venous catheter implantation is not associated with an increased risk of cutaneous or infectious complications. However, continuation of long-term parenteral nutrition requires monitoring in an expert nutrition center in order to adapt nutritional volumes and intakes and to limit potentially fatal cardiac and hepatobiliary complications. In addition to nutrition, prokinetic treatments, whose side effects must be known, can be associated. Invasive procedures, whose risk-benefit ratio must be carefully assessed, can also be used to treat symptoms exclusively.


Assuntos
Pseudo-Obstrução Intestinal , Escleroderma Sistêmico , Humanos , Pseudo-Obstrução Intestinal/diagnóstico , Pseudo-Obstrução Intestinal/etiologia , Pseudo-Obstrução Intestinal/terapia , Nutrição Parenteral/efeitos adversos , Intestino Delgado , Escleroderma Sistêmico/complicações , Escleroderma Sistêmico/diagnóstico , Escleroderma Sistêmico/terapia , Medição de Risco , Doença Crônica
7.
PLoS One ; 19(1): e0295062, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38232097

RESUMO

Tardigrades, commonly known as 'waterbears', are eight-legged microscopic invertebrates renowned for their ability to withstand extreme stressors, including high osmotic pressure, freezing temperatures, and complete desiccation. Limb retraction and substantial decreases to their internal water stores results in the tun state, greatly increasing their ability to survive. Emergence from the tun state and/or activity regain follows stress removal, where resumption of life cycle occurs as if stasis never occurred. However, the mechanism(s) through which tardigrades initiate tun formation is yet to be uncovered. Herein, we use chemobiosis to demonstrate that tardigrade tun formation is mediated by reactive oxygen species (ROS). We further reveal that tuns are dependent on reversible cysteine oxidation, and that this reversible cysteine oxidation is facilitated by the release of intracellular reactive oxygen species (ROS). We provide the first empirical evidence of chemobiosis and map the initiation and survival of tardigrades via osmobiosis, chemobiosis, and cryobiosis. In vivo electron paramagnetic spectrometry suggests an intracellular release of reactive oxygen species following stress induction; when this release is quenched through the application of exogenous antioxidants, the tardigrades can no longer survive osmotic stress. Together, this work suggests a conserved dependence of reversible cysteine oxidation across distinct tardigrade cryptobioses.


Assuntos
Cisteína , Tardígrados , Animais , Espécies Reativas de Oxigênio , Invertebrados , Congelamento
8.
Animals (Basel) ; 13(22)2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-38003060

RESUMO

Three Lactococcus lactis strains from the nasal microbiota of healthy pigs were identified as candidates for reducing MRSA in pigs. The safety of nasal administration of a cocktail of these strains was examined in new-born piglets. Six days pre-farrowing, twelve sows were assigned to the placebo or cocktail group (n = 6/group). After farrowing, piglets were administered with either 0.5 mL of the placebo or the cocktail to each nostril. Health status and body weight were monitored at regular time points. Two piglets from three sows/treatment group were euthanised at 24 h, 96 h and 14 d after birth, and conchae, lung and tonsil samples were collected for histopathological and gene expression analysis. Health scores were improved in the cocktail group between d1-5. Body weight and daily gains did not differ between groups. Both groups displayed histological indications of euthanasia and inflammation in the lungs, signifying the findings were not treatment related. The expression of pBD2, TLR9 and IL-1ß in the nasal conchae differed between groups, indicating the cocktail has the potential to modulate immune responses. In summary, the L. lactis cocktail was well tolerated by piglets and there was no negative impact on health scores, growth or lung histopathology indicating that it is safe for administration to new-born piglets.

9.
Lang Learn Dev ; 19(4): 369-385, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37771762

RESUMO

Socioeconomic status (SES)-related language gaps are known to widen throughout the course of the school years; however, not all children from lower SES homes perform worse than their higher SES peers on measures of language. The current study uses mediation and moderated mediation to examine how cognitive and language abilities (vocabulary, reading, phonological processing, working memory) account for individual differences in a children's ability to infer a novel word's meaning, a key component in word learning, in school-aged children from varying SES backgrounds. Vocabulary and reading comprehension mediated the relationship between SES and accuracy when inferring word meanings. The relationship between SES, vocabulary, and inferring word meaning was moderated by age, such that the influence of vocabulary on task performance was strongest in young children. The reading pathway did not interact with age effects, indicating reading is an important contributor to SES-related differences in how children infer a word's meaning throughout grade school. These findings highlight different paths by which children's trajectories for inferring word meanings may be impacted.

10.
Ann Work Expo Health ; 67(8): 1004-1010, 2023 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-37300560

RESUMO

Methicillin-resistant strains of Staphylococcus aureus (MRSA) are resistant to most ß-lactam antibiotics. Pigs are an important reservoir of livestock-associated MRSA (LA-MRSA), which is genetically distinct from both hospital and community-acquired MRSA. Occupational exposure to pigs on farms can lead to LA-MRSA carriage by workers. There is a growing body of research on MRSA found in the farm environment, the airborne route of transmission, and its implication on human health. This study aims to directly compare two sampling methods used to measure airborne MRSA in the farm environment; passive dust sampling with electrostatic dust fall collectors (EDCs), and active inhalable dust sampling using stationary air pumps with Gesamtstaubprobenahme (GSP) sampling heads containing Teflon filters. Paired dust samples using EDCs and GSP samplers, totaling 87 samples, were taken from 7 Dutch pig farms, in multiple compartments housing pigs of varying ages. Total nucleic acids of both types of dust samples were extracted and targets indicating MRSA (femA, nuc, mecA) and total bacterial count (16S rRNA) were quantified using quantitative real-time PCRs. MRSA could be measured from all GSP samples and in 94% of the EDCs, additionally MRSA was present on every farm sampled. There was a strong positive relationship between the paired MRSA levels found in EDCs and those measured on filters (Normalized by 16S rRNA; Pearson's correlation coefficient r = 0.94, Not Normalized; Pearson's correlation coefficient r = 0.84). This study suggests that EDCs can be used as an affordable and easily standardized method for quantifying airborne MRSA levels in the pig farm setting.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Exposição Ocupacional , Infecções Estafilocócicas , Suínos , Humanos , Animais , Fazendas , RNA Ribossômico 16S , Poeira/análise , Infecções Estafilocócicas/veterinária , Exposição Ocupacional/análise
11.
Methods Mol Biol ; 2669: 79-109, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37247056

RESUMO

Hepatic stellate cells (HSCs) are the key effector cells in liver fibrosis. They are the main producers of excessive amounts of extracellular matrix components during fibrogenesis and therefore a potential target for the treatment of liver fibrosis. Induction of senescence in HSCs may be a promising strategy to slow down, stop, or even reverse fibrogenesis. Senescence is a complex and heterogeneous process linked to fibrosis and cancer, but the exact mechanism and relevant markers can be cell-type dependent. Therefore, many markers of senescence have been proposed, and many methods to detect senescence have been developed. In this chapter, we review relevant methods and biomarkers to detect cellular senescence in hepatic stellate cells.


Assuntos
Células Estreladas do Fígado , Células de Kupffer , Humanos , Senescência Celular , Cirrose Hepática , Pesquisa , Fígado
12.
IEEE J Biomed Health Inform ; 27(6): 3083-3092, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37030704

RESUMO

One of the major goals in gene expression data analysis is to explore and discover groups of genes and groups of biological conditions with meaningful relationships. While this problem can be addressed by algorithms, their results require an analysis within context, since they may be affected by many side processes -such as tissue differentiation- that could hinder the target goal. Visual analytics-based methods for exploratory analysis of the gene expression matrix (GEM) are essential in biomedical research since they allow us to frame the analysis within the user's knowledge domain. In this paper, we present a visual analytics approach to discover relevant connections between genes and samples based on linking a reordered GEM heatmap and dual 2D projections of its rows and columns, which can be recomputed conditioned by subsets of genes and/or samples selected by the user during the analysis. We demonstrate the capability of our approach to discover relevant knowledge in three case studies involving two cancer types plus normal tissue from the TCGA database.


Assuntos
Algoritmos , Perfilação da Expressão Gênica , Humanos , Perfilação da Expressão Gênica/métodos , Bases de Dados Genéticas , Expressão Gênica
13.
Eur Heart J Qual Care Clin Outcomes ; 9(3): 281-292, 2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35723241

RESUMO

AIMS: We report associations between different formulae for estimating plasma volume status (PVS) and clinical and ultrasound markers of congestion in patients with chronic heart failure (CHF) enrolled in the Hull Lifelab registry. METHODS AND RESULTS: Cohort 1 comprised patients with data on signs and symptoms at initial evaluation (n = 3505). Cohort 2 included patients with ultrasound assessment of congestion [lung B-line count, inferior vena cava (IVC) diameter, jugular vein distensibility (JVD) ratio] (N = 341). Two formulae for PVS were used: (a) Hakim (HPVS) and (b) Duarte (DPVS). Results were compared with clinical and ultrasound markers of congestion. Outcomes assessed were mortality and the composite of heart failure (HF) hospitalisation and all-cause mortality. In cohort 1, HPVS was associated with mortality [hazard ratio (HR) per unitary increase = 1.02 (1.01-1.03); P < 0.001]. In cohort 2, HPVS was associated with B-line count (HR) = 1.05 [95% confidence interval (CI) (1.01-1.08); P = 0.02] and DPVS with the composite outcome [HR = 1.26 (1.01-1.58); P = 0.04]. HPVS and DPVS were strongly related to haemoglobin concentration and HPVS to weight. After multivariable analysis, there were no strong or consistent associations between PVS and measures of congestion, severity of symptoms, or outcome. By contrast, log[NTproBNP] was strongly associated with all three. CONCLUSION: Amongst patients with CHF, HPVS and DPVS are not strongly or consistently associated with clinical or ultrasound evidence of congestion, nor clinical outcomes after multivariable adjustment. They appear only to be surrogates of the variables from which they are calculated with no intrinsic clinical utility.


Assuntos
Insuficiência Cardíaca , Volume Plasmático , Humanos , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/diagnóstico , Doença Crônica , Hospitalização
16.
Polymers (Basel) ; 14(24)2022 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-36559783

RESUMO

Emerging dye pollution from textile industrial effluents is becoming more challenging for researchers worldwide. The contamination of water by dye effluents affects the living organisms in an ecosystem. Methylene blue (MB) and malachite green (MG) are soluble dyes with a high colour intensity even at low concentration and are hazardous to living organisms. The adsorption method is used in most wastewater plants for the removal of organic pollutants as it is cost-effective, has a high adsorption capacity, and good mechanical stabilities. In this study, a composite adsorbent was prepared by impregnating iron modified silica (FMS) onto polyurethane (PU) foam to produce an iron modified silica/polyurethane (FMS/PU) composite. The composite adsorbent was utilised in batch adsorption of the cationic dyes MB and MG. The effect of adsorption parameters such as the adsorbent load, pH, initial dye concentration, and contact time were discussed. Adsorption kinetics and isotherm were implemented to understand the adsorption mechanism for both dyes. It was found that the adsorption of MB and MG followed the pseudo-second order model. The Langmuir model showed a better fit than the Freundlich model for the adsorption of MB and MG, indicating that the adsorption occurred via the monolayer adsorption system. The maximum adsorption capacity of the FMS/PU obtained for MB was 31.7 mg/g, while for MG, it was 34.3 mg/g. The thermodynamic study revealed that the adsorption of MB and MG were exothermic and spontaneous at room temperature. In addition, the regeneration of FMS/PU was conducted to investigate the composite efficiency in adsorbing dyes for several cycles. The results showed that the FMS/PU composite could be regenerated up to four times when the regeneration efficiency dropped drastically to less than 20.0%. The impregnation of FMS onto PU foam also minimised the adsorbent loss into the environment.

17.
Science ; 378(6622): 915-920, 2022 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-36423285

RESUMO

Grazing represents the most extensive use of land worldwide. Yet its impacts on ecosystem services remain uncertain because pervasive interactions between grazing pressure, climate, soil properties, and biodiversity may occur but have never been addressed simultaneously. Using a standardized survey at 98 sites across six continents, we show that interactions between grazing pressure, climate, soil, and biodiversity are critical to explain the delivery of fundamental ecosystem services across drylands worldwide. Increasing grazing pressure reduced ecosystem service delivery in warmer and species-poor drylands, whereas positive effects of grazing were observed in colder and species-rich areas. Considering interactions between grazing and local abiotic and biotic factors is key for understanding the fate of dryland ecosystems under climate change and increasing human pressure.


Assuntos
Biodiversidade , Herbivoria , Gado , Mudança Climática , Solo
18.
Microorganisms ; 10(9)2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36144356

RESUMO

Herpesviruses are double-stranded DNA viruses occurring at a high prevalence in the human population and are responsible for a wide array of clinical manifestations and diseases, from mild to severe. These viruses are classified in three subfamilies (Alpha-, Beta- and Gammaherpesvirinae), with eight members currently known to infect humans. Importantly, all herpesviruses can establish lifelong latent infections with symptomatic or asymptomatic lytic reactivations. Accumulating evidence suggest that chemical modifications of viral RNA and DNA during the lytic and latent phases of the infections caused by these viruses, are likely to play relevant roles in key aspects of the life cycle of these viruses by modulating and regulating their replication, establishment of latency and evasion of the host antiviral response. Here, we review and discuss current evidence regarding epitranscriptomic and epigenetic modifications of herpesviruses and how these can influence their life cycles. While epitranscriptomic modifications such as m6A are the most studied to date and relate to positive effects over the replication of herpesviruses, epigenetic modifications of the viral genome are generally associated with defense mechanisms of the host cells to suppress viral gene transcription. However, herpesviruses can modulate these modifications to their own benefit to persist in the host, undergo latency and sporadically reactivate.

19.
Heliyon ; 8(5): e09350, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35574195

RESUMO

Aluminum alloy and its composites have versatile applications and can be produced via a cost-effective stir casting technique. However, stir casting is faced with some challenges including segregation, occurrence of intermetallic phases, agglomeration, and inducement of residual stress. In view of minimizing these defects, casting should be done applying optimal parameters that will yield the desired outcome. The present study focused on the optimization of stirring parameters of temperature, speed, and time in the production of Al 6061/glass powder composite. Evaluated responses are tensile strength, compressive strength, impact strength, and hardness. The results showed that the process parameters had statistical significance on all properties at 95 % confidence level. Combined interactions of these parameters also presented significant effects on the property responses. Optimum setting for process factors as regards tensile strength were evaluated to be 600 °C, 400 rpm, and 30 min for temperature, speed, and time, respectively. For compressive strength, it is 600 °C, 500 rpm, and 30 min; for hardness, the optimum settings are 700 °C, 400 rpm, and 30 min, while in the case of impact strength, the optimum settings are 500 °C, 400 rpm, and 30 min respectively. Optimization of the combined characteristics was obtained at the optimum conditions of 500 °C, 400 rpm, and 30 min for stirring temperature, speed, and time. Moreso, the significance of the parameters on the composite in descending order is temperature, time, and speed.

20.
Zootaxa ; 5124(4): 431-457, 2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35391112

RESUMO

Huriini Simon, 1901 currently consists of six genera and 17 species, distributed exclusively in South America. In this work, the huriine genus Guriurius Marta, Bustamante, Ruiz Rodrigues, gen. nov. is proposed with two new species herein described: Guriurius minuano Marta, Bustamante, Ruiz Rodrigues, sp. nov. (type species) and Guriurius nancyae Marta, Bustamante, Ruiz Rodrigues, sp. nov. The female of Atelurius segmentatus Simon, 1901 is described and illustrated for the first time. Scoturius dipterioides Perger Rubio, 2018 is transferred to Atelurius Simon, 1901 due to the morphological similarity of copulatory ducts of epigyne, and Hurius pisac Galiano, 1985 is transferred to Simonurius Galiano, 1988 due to the similarities in body shape and female genitalia. Simonurius campestratus (Simon, 1901) is synonymized with Simonurius quadratarius (Simon, 1901). The interpretation of genitalic characters in Huriini is discussed. In addition, we provide new distributional records for Admesturius bitaeniatus (Simon, 1901), Ad. mariaeugeniae Bustamante Scioscia, 2014, Ad. schajovskoyi Galiano, 1988, At. segmentatus Simon, 1901, Scoturius tigris Simon, 1901, Hurius aeneus (Mello-Leito, 1941), and Simonurius gladifer (Simon, 1901). Except for Urupuyu Ruiz Maddison, 2015, all huriine genera are rediagnosed in the new context of tribe and genus composition.


Assuntos
Aranhas , Distribuição Animal , Animais , Feminino
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