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Abstract Zebrafish have become an important model animal for studying the emergence of collective behavior in nature. Here, we show how to properly analyze the polarization statistics to distinguish shoal regimes. In analogy with the statistical properties of optical speckles, we show that exponential and Rayleigh distributions emerge in shoals with many fish with uncorrelated velocity directions. In the opposite limit of just two fish, the polarization distribution peaks at high polarity, with the average value being a decreasing function of the shoal’s size, even in the absence of correlations. We also perform a set of experiments unveiling two shoaling regimes. Large shoals behave as small domains with strong intra-domain and weak inter-domain correlations. A strongly correlated regime develops for small shoals. The reported polarization statistical features shall guide future automated neuroscience, pharmacological, toxicological, and embryogenesis-motivated experiments aiming to explore the collective behavior of fish shoals.

Finding prehistoric sites, on the sea floor off the United States, has proven to be a difficult task. Over four decades of innovative attempts have produced few discoveries. This discussion outlines the difficulties in finding submerged prehistory on the sea floor, examines current methodology(ies), and presents a new methodology that demonstrates promise based on research conducted over the past decade. The purpose of this discussion is to outline the problems facing archaeologists searching the sea floor for archaeological sites. It is less of a critique of past efforts and methodologies used in those attempts. Without those efforts, a reason for developing a different methodological approach would be unnecessary. Any “one size fits all” methodology is limiting, and the scant number of marine archaeological sites located off the shores of the United States can attest to the need for practitioners to continue refining their methods. This is especially the case on the continental shelf of the eastern United States, where sediment cover is often meters, or several meters, thick. This opportunistic methodology developed on the continental shelf of the Georgia Bight, western Atlantic Ocean, has located intact paleo-landforms with in situ, palaeoecological remains thereby offering promise for future archaeological discoveries.

Testing of inverter-based resources (IBRs) faces challenges in establishing standardized procedures across all product development stages. Most of the testing approaches use Hardware-in-the-Loop (HIL) during the early stages independently from the final product testing, which can lead to discrepant results. To solve these issues, this paper proposes a unified platform for automatically testing IBRs. It can be used during all product development stages, from pure simulation to Controller Hardware-in-the-Loop (CHIL) and finally on the complete commercial product, ensuring uniform test procedures with different test setups. A case study describing compliance tests of grid-connection codes of photovoltaic (PV) inverters are presented to demonstrate the proposed approach. Experimental tests were performed in accordance to Brazilian grid-connection codes in an ISO/IEC 17025 accredited laboratory. The results obtained with the proposed platform in CHIL and full-hardware showed high similarity with the ones obtained with the accredited laboratory, validating the proposed approach. In addition, the platform can be used to perform tests not specified in standards and to verify the performance of IBRs in operating conditions that are often difficult to be tested in laboratory. Ensuring consistent test procedures, the platform facilitates comparable results along all the testing stages, reducing the product development cycle.

This study aimed to develop a learning device based on ethnomathematics of the Meher tribe woven fabrics (Kisar Island) with a Realistic Mathematics Education (RME) approach on number pattern material for 8th-grade students of Public Junior High School 4 Southern Islands. The learning devices developed consisted of Learning Implementation Plans (RPP), Teaching Materials (BA), and Student Worksheets (LKPD). The development model used was the 4-D model, which consisted of four stages, namely define, design, develop, and disseminate but were limited to the development stage. The device was tested for quality (valid, practical and effective). Following the validation results by the five validators, it was found that the devices developed met the validity requirements with an average score of Learning Implementation Plans (RPP) 3.5 (very good), an average score of Teaching Materials (BA) 3.3 (good), the average score of Student Worksheets (LKPD) was 3.4 (good). The average validator's general assessment was 3.3 (good). According to the practicality test of the developed devices, it was found that the developed devices were categorized as practical, with an average positive response of educators of 100% and an average positive response of students of 91.3%. The developed devices also fulfilled the effectiveness requirements by achieving a classical completeness percentage of 79.2%. The results of the study obtained the quality of the devices developed

Abstract With the advent of novel and emerging technologies, long duration spaceflight will become more common; along with it, an increase in its inherent health risks. However, health-related ethical issues arising during long-duration spaceflight remain poorly characterized, uncertain and unpredictable. Medical ethics is defined as a set of moral principles, beliefs and values that guides choices about medical care. This set of principles, founded in our sense of right and wrong, helps us make fair and just decisions. The paper conceptually and analytically investigates the ethical issues likely to arise from medical complications during spaceflight, mapping unfilled gaps of the current status quo. Furthermore, this paper explores broad ethical themes of autonomy, nonmaleficence, beneficence and justice, while also delving deeper into specific scenarios within each theme. The manuscript represents an up-to-date review of the available literature in the field of space medical ethics and recommends guiding ethical principles and a framework for their application to negotiate the resolution of complex ethical scenarios during long-duration spaceflight.

Althea Gamble Blakey,1 Lynley Anderson,2 Kelby Smith-Han,3 Emma Collins,4 Elizabeth Berryman,5 Tim J Wilkinson1 1Otago Medical School, University of Otago, Dunedin, New Zealand; 2Bioethics Centre, University of Otago, Dunedin, New Zealand; 3Medical Education Unit, University of Western Australia, Perth, Australia; 4Department of Women’s and Children’s Health, University of Otago, Dunedin, New Zealand; 5Chnnl Limited, Auckland, New ZealandCorrespondence: Althea Gamble Blakey, Otago Medical School, University of Otago, Sayers Building, Dunedin, New Zealand, Email althea.blakey@otago.ac.nzBackground: Medical student and health-care staff bullying remain international concerns. Our understanding about what might solve such problems is still developing. A common approach suggested for bystanders to bullying is that they challenge or “stand up” to the bully. At the same time, the considerable risks should they act (eg, verbal rebuke) are rarely acknowledged, and neither is the potential for considerable cognitive dissonance should they choose not to.Methods: Drawing on a substantial literature review, we developed an interventional program, initially with medical student bullying in mind, that generally employed a discourse for values cultivation. We implemented and evaluated this program through 6 cycles of action research methodology in 6 different departments of one tertiary teaching hospital. Data include individual interviews, discussions with key participants plus freehand comments from wider staff’s workshop evaluations.Results: Alongside others, an early serendipitous finding was the “IMO” [Indirect, focus on Me, focus on Outcome] framework, intended for bystanders to student bullying. From using this framework, participants reported developing confidence in tackling negative behaviours, that interactions had better outcomes and that the workplace atmosphere felt more relaxed. It’s use also significantly reduced cognitive dissonance. Encouragingly, participants went on to use IMO for staff–staff bullying incidents, and other common negative behaviours. We attribute IMO’s utility to its memorability, simplicity and for catering to the many possible causes of bullying, including values issues, without perpetuating or creating conflict.Conclusion: The IMO framework is offered as a widely usable framework for all staff in a clinical environment – a useful addition to popular frameworks used in the clinical workplace, ideas from which might also help these be further refined. Further evaluation would establish whether IMO invites long-term change and its utility in other contexts.Keywords: bullying, bystander, clinical environment, framework, IMO, intervention, medical student, onlooker, verbal

6G networks are expected to use the terahertz (THz) frequency spectrum in some way. However, relatively little is known about the transmission channel in this part of the spectrum. In this article, we propose a novel and accurate channel loss model that considers both molecular and water vapor continuum absorptions for THz networks based on the frequency range between 100 GHz and 600 GHz. The proposed channel model assumes that the atmospheric absorption is accurately accounted for by the molecular absorption coefficient and the water vapor continuum absorption coefficient. The new model is based on equations developed to accurately match the channel response given by a spectroscopic database. This makes the channel model robust and useful for evaluating the performance of THz networks. The model is validated against a spectroscopic database defined as a benchmark. The performance of the new channel loss model is evaluated against different models, including several error metrics. Numerical results show the new channel model is as accurate as the spectroscopic database by correctly reproducing the provided experimental dataset. Therefore, the proposed channel model is a reliable, robust and simple tool that can be successfully used to carry out performance evaluation of THz networks with accuracy.

Este trabalho tem como objetivo apresentar uma introdução ao grupo S O ( 4 ) e duas aplicações na Física: uma na Mecânica Clássica e outra na Mecânica Quântica. Os geradores do grupo S O ( 4 ) serão determinados, assim como sua álgebra de Lie. A aplicação na Mecânica Clássica será na obtenção da transformação de Galilei homogênea e na Mecânica Quântica será na obtenção do espectro de energia do átomo de hidrogênio, no regime não-relativístico. A versão quântica do vetor de Laplace-Runge-Lenz será fundamental para a construção da fórmula de Bohr para os níveis de energia do respectivo átomo.

Neste trabalho apresentaremos uma introdução à Física do Monopolo Magnético no regime não – relativístico. O tratamento clássico de um sistema composto por uma partícula pontual eletricamente carregada na presence de um monopolo magnético na origem, com suas equações de movimento e o estudo do potencial vetor de Dirac, será desenvolvido ao longo do presente trabalho. A questão das singularidades e as transformações de calibre serão também tratadas. Ao final, listaremos alguns modelos análogos ao monopolo magnético, utilizando outros sistemas físicos.

Industrial applications with robotic manipulators have grown and made production systems increasingly efficient. However, there are still some limitations that can delay production, causing losses. Several factors, such as accidents and collisions of manipulator robots with operators and other machines, can cause unforeseen stops. Thus, this work aims to develop a trajectory planning method to avoid collisions applied to a selective compliance assembly robot arm (SCARA) robotic manipulator in the context of collaborative robotics. The main contribution of this paper is a path planning method based on mathematical morphology, named topological path planning (TPP). Through some evaluation metrics such as the number of path points, computing time, distance, standard deviation of the joint acceleration, and maximum acceleration rate along the path, we show that TPP is a collision-free, deterministic, and predictable route planning. In our experiments, our proposal presented better results for applications in industrial robotic manipulators when compared to the probabilistic roadmap method (PRM) and TPP*, a particular case of TPP that is similar to the generalized Voronoi diagram (GVD).

Penelitian ini bertujuan untuk mengetahui ada tidaknya perbedaan hasil belajar siswa kelas VII SMP Negeri 9 Ambon yang diajarkan dengan menggunakan model pembelajaran Kooperatif Tipe Team Assisted Individualization (TAI) dan Model Pembelajaran Konvensional pada Materi Operasi Hitung Bentuk Aljabar. Tipe penelitian yang digunakan adalah Eksperimen dengan Post only grup design. Populasi pada penelitian ini adalah seluruh siswa kelas VII SMP Negeri 9 Ambon yang terdiri dari tujuh kelas dengan jumlah siswa 216 orang. Dari populasi tersebut di pilih dua kelas sebagai sampel dengan menggunakan teknik purposive sampling. Kedua kelas yang terpilih yaitu kelas VII-1 sebagai kelas eksperimen dan VII-3 sebagai kelas control. Hasil penelitian menunjukan bahwa terdapat perbedaan hasil belajar siswa kelas VII SMP Negeri 9 Ambon yang diajarkan dengan menggunakan model pembelajaran kooperatif tipe team assisted individualization (TAI) dan model pembelajaran konvensional pada materi operasi hitung bentuk aljabar. Hasil pengujiaan hipotesis dengan menggunakaan uji-t pada SPSS 20,0 menunjukan bahwa sig (2-tailed) kurang dari (0,001

Purpose: To report successful ring-shaped iodine-125 plaque brachytherapy for conjunctival melanoma. Observations: Eye Physics (EP) plaque brachytherapy, designed with Plaque Simulator software, proved to be an effective treatment modality with some corneal irritation and no recurrence at 12-months post radiation. Conclusion and importance: Management of conjunctival melanoma is complicated by the lack of gold standard adjuvant treatments. I-125 EP plaque brachytherapy represents a viable option for these malignancies. Specifically, ring-shaped plaque geometries allow for targeted radiotherapy.

The purpose of this report is to describe biopsy-proven ocular sarcoidosis (OS) in a 67-year-old patient with a history of sarcoidosis and diffuse large B-cell lymphoma (DLBCL). Nonspecific posterior chorioretinal lesions in a patient with prior malignancy necessitated chorioretinal biopsy to rule out metastatic lymphoma. The association between sarcoidosis and malignancy remains unclear and can complicate management of similar patients with nonspecific posterior segment findings. Chorioretinal biopsy may, therefore, be required to rule out malignancy in patients with a leading history.

The purpose of this article is to present and reaffirm the importance of shared public health management on the Brazil-Bolivia border. To this end, bibliographic and documentary surveys were carried out, as well as interviews with 14 experts who form the Community of Inquiry, an investigation method developed by John Dewey that provides a useful lens for studies on shared management, as it emphasizes the plurality of actors beyond the actions of the State, demonstrating how public health problems are dealt with in the region. Specifically, we detail part of COVID-19's first operations (February to June 2020) in the municipalities of Corumbá and Ladário (Brazil) and Puerto Quijarro and Puerto Suarez (Bolivia). Recognizing the political dimension of the problematic situation, we rekindle the importance of governance for combating the COVID-19 pandemic and for the shared management of other urgent local epidemics, such as dengue and H1N1 on the border.

Abstract Although Brazil has one of the largest buffalo populations in the Americas, buffalo leptospirosis is still poorly explored when compared to that in bovines; thus, the aim of this research was to carry out a large serological study for leptospirosis in this species in the Brazilian Amazon. For this, we collected 1,405 serum samples from buffaloes raised in the Amazon delta region, which is considered a major area of buffalo production in Brazil. The test used was a microscopic agglutination test (MAT) adopting 34 Leptospira antigens, some of which have never been tested for buffaloes in Brazil, including autochthonous strains; in total, 20 serogroups were evaluated. From the total of 1,405 serum samples, 894 (63.6%) reacted in the MAT to at least one of the 20 serogroups, and 511 (36.4%) did not react. The serogroups Sejroe, Autumnalis and Pomona were the most prevalent, with titres ranging from 100 to 12,800, and the autochthonous strains used were not significant in relation to the reference serovars. Leptospirosis in buffaloes seems to have a serological profile similar to leptospirosis in cattle, mainly due to the prevalence of the Sejroe serogroup; however, the results of this study suggested that in the Brazilian Amazon, Leptospira strains that are serologically distinct from the autochthonous strains isolated in the southeastern region of Brazil may be circulating in these animals. Other serovars could also be inserted into the panel of antigens used in MAT for serological studies on buffaloes.

Penelitian ini bertujuan untuk mengetahui peningkatan hasil belajar peserta didik pada materi sistem persamaan linear dua variabel melalui model pembelajaran flipped classroom di kelas VIII SMP Negeri 15 Ambon. Subjek penelitian ini adalah peserta didik kelas VIII6 SMP Negeri 15 Ambon yang berjumlah 25 orang, jenis penelitian ini adalah penelitian tindakan kelas. Penelitian ini dilaksanakan dalam tiga siklus dengan 5 pertemuan. Data penelitian ini dikumpulkan melalui lembar observasi dan tes. Hasil analisis menunjukkan bahwa setelah diberikan tindakan pada siklus I peserta didik yang mencapai ketuntasan sebanyak 6 orang dengan pencapaian 24%, dan pada siklus II diperoleh jumlah peserta didik yang mencapai ketuntasan 11 orang dengan pencapaian 44%, selanjutnya pada siklus III terjadi peningkatan yaitu diperoleh jumlah peserta didik yang mencapai ketuntasan 23 orang dengan pencapaian 92%. Dilihat hasil tes peserta didik dari siklus II dan siklus III maka telah terjadi peningkatan yaitu sebesar 48% dengan menggunakan model pembelajaran flipped classroom pada materi sistem persamaan linear dua variabel di kelas VIII SMP Negeri 15 Ambon

In this paper, we are concerned with the existence of at least three distinct solutions for discrete boundary value problems. The proof of the main result is based on variational methods. We also provide two examples in order to illustrate the main results.

Individuals with lower-limb amputations may have a significant strength deficit. This deficit may be related to the stump length and can lead to changes in gait, reduced energy efficiency, walking resistance, altered joint load, and increased risk of osteoarthritis and chronic low back pain. This systematic review used the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes (PRISMA) guidelines to examine the effects of resistance training in lower limb amputees. Interventions with resistance training and other training methods were sufficient to achieve muscle strength gain in muscles of the lower limbs, improved balance, and improvements in gait pattern and speed when walking. However, it was impossible to determine from the results whether resistance training was mainly responsible for these benefits or even whether the positive effects presented would be observed with only this training method. When combined with other exercises, interventions with resistance training made possible gains for this population. Accordingly, it is noteworthy that the main finding of this systematic review is that the effects may be different according to the level of amputation, with mainly transtibial and transfemoral amputations studied.

The Brazilian Midwest has significant spatiotemporal variability in terms of precipitation and air temperature, making it more vulnerable to the occurrence of extreme weather events. The objective of this study is to characterize the trend of extreme climatic events regarding precipitation and air temperature in the Brazilian Midwest, and to analyze their relationship with Pacific and Atlantic Sea Surface Temperature anomalies (SSTAs). We used daily precipitation and air temperature data measured at 24 conventional weather stations. Pacific and Atlantic SSTA data were obtained from the Climate Prediction Center. The frequency of hot extremes had increased, while that of cold extremes had decreased significantly, thus highlighting the consistent warming across the Brazilian Midwest. The precipitation extremes had greater variability than the temperature extremes. Precipitation intensity increased in Amazonia, with no change in annual precipitation volume. The precipitation extremes in the Brazilian Savanna, Pantanal, and the Atlantic Forest did not have a well-defined pattern but indicated a trend towards a decrease in days with intense precipitation events. In general, the Equatorial Pacific and Atlantic Ocean (TNAI and TSAI) SSTAs were negatively correlated with precipitation extreme indices and positively correlated with air temperature extreme indices in the Amazon. However, the North Atlantic SSTAs were positively correlated with precipitation and air temperature extreme indices in the Brazilian Savanna and Pantanal. In addition, the Pacific SSTAs were positively correlated with precipitation intensity in the Atlantic Forest. Thus, the variability of the trends of precipitation and air temperature extreme indices in the Brazilian Midwest was observed, and it was surmised that this measure was significantly related to Pacific and Atlantic SSTAs.

Objetivos: Avaliar o perfil de uso de antimicrobianos na unidade de terapia intensiva (UTI), após implementação do Antimicrobial Stewardship Program (ASP). Métodos: estudo do tipo antes e depois da implementação do programa, realizado de janeiro a dezembro de 2018, envolvendo pacientes com mais de 18 anos, que estiveram internados na UTI, com solicitação de análise microbiológica para apoio diagnóstico de infecção presumida ou confirmada e em uso de antimicrobianos. Foram comparados os resultados dos períodos anterior e posterior à implantação do ASP (1º semestre/2018 versus 2º semestre/2018). Os dados secundários foram obtidos por meio de prontuários e software da unidade de estudo. Foi feita a caracterização da distribuição dos pacientes e monitoradas as variáveis: DDD/1000 pacientes-dia, internados na UTI, número de solicitações de tratamento, média de uso de antimicrobianos por paciente e proporção do consumo de antibióticos, obedecendo à categorização AWaRe. Para análise estatística, foram utilizados os testes t-Student com variâncias desiguais, t-Student com variâncias iguais e teste Mann-Whitney. Resultados: No total, 461 pacientes foram incluídos no estudo. Observou-se que o meropenem foi o antimicrobiano com maior DDD/1000 pacientes-dia em ambos os semestres avaliados (696,67 ± 120,95 versus 481,08 ± 145,23), seguido da vancomicina (316,50 ± 59,89 versus 311,71 ± 89,52). No período pós-intervenção do ASP, houve redução significativa da DDD/1000 pacientes-dia para os antibióticos Meropenem (p = 0,020) e Polimixina B (p = 0,007) e aumento para Piperacilina/Tazobactam. Observou-se um total de 1.605 solicitações de tratamento antimicrobiano em 2018, com redução significativa após intervenção do ASP (147,50 ± 16,63 versus 120,00 ± 18,34, p = 0,022). Considerando a classificação AWaRe, os antibióticos mais utilizados em 2018, em ambos os semestres, corresponderam aos de “Vigilância” (64%), seguidos dos classificados como “Reserva” (21%) e por fim, os de “Acesso” (15%). Conclusões: os resultados apontaram a redução do uso de antimicrobianos, especialmente de antibióticos de amplo espectro, após a intervenção do ASP, o que era esperado, visto que esta é uma ferramenta importante no manejo da terapia antimicrobiana em pacientes acometidos por infecção em unidade de cuidados críticos.

This study aims to describe the mathematical communication skills of prospective teacher students in solving mathematical problems Evaluated from Personality Types (artisan, idealist, guardian, dan rational). This research is a kind of qualitative exploratory research. The subjects used in this study were students of the 4th semester Mathematics Education consisting of 1 student for each type of artisan personality (SA), idealist personality (SI), guardian personality (SG), and rational personality (SR). The selection of research subjects is based on stratified sampling technique then purposive sampling. Data analysis techniques refer to the concept of Miles and Huberman which includes data reduction, data presentation, and drawing conclusions. The data validity technique uses the method triangulation and source triangulation. The results of the research show that: 1) SA meets three indicators namely being able to write information that is known and asked, draw pictures, and do calculations; 2) SI fulfills four indicators which are able to write information that is known and asked, draw pictures, do calculations, and apply mathematical symbols and rules in accordance with the intended problem; 3) SG fulfills three indicators namely being able to make drawings, do calculations, and write symbols and mathematical rules; 4) SR fulfills two indicators namely being able to write information that is known and asked, and doing calculations.

Abstract Conyza species are important weeds in global agriculture, especially due to their capacity to evolve resistance to multiple herbicide mechanisms of action. We aimed to evaluate the frequency and distribution of resistance to glyphosate and chlorimuron-ethyl in Conyza spp. populations from Brazil. Seed samples were collected from grain production areas across nine Brazilian states over five consecutive years (2014 to 2018). Prior to resistance monitoring trials, dose-response assays were conducted to determine a single dose of glyphosate or chlorimuron-ethyl to discriminate resistant and susceptible populations. Resistance monitoring based on plant responses to the application of discriminatory doses of glyphosate (960 g ha-1) or chlorimuron-ethyl (20 g ha-1). Populations were classified as resistant, moderately resistant, or susceptible to either herbicide. While glyphosate resistance was highly frequent (71.2%) in all the five years, chlorimuron-ethyl resistant populations occurred at 39.8% of the total. The frequency of multiple resistance to both herbicides (35.3%) was proportional to the occurrence of chlorimuron-ethyl resistance (39.6%). Resistance to glyphosate and to chlorimuron-ethyl were found across all states evaluated.

Here, we describe 4-dimethylaminoantipyrine (4-DMAA)-mediated interfacing as a broad biochemical indicator to stabilize and promote the higher response of electrodes for immunological detection. We hypothesized that the improved biological interactions of 4-DMAA with electrodes and biological samples may be due to the interaction properties of the benzene and pyrazole chemical groups with graphite and proteins, respectively. In order to demonstrate that 4-DMAA could be used as a general indicator in electrochemical immunoassays, we used peptides as probes for the diagnosis of four neglected tropical infectious diseases Tegumentary leishmaniasis, Visceral leishmaniasis, Strongyloidiasis, and Leprosy on commercial graphite screen-printed electrodes. 4-DMAA oxidation was used to indicate specific biological recognition between the epitope-based peptide and serum immunoglobulin G (IgG) from infected patients. We demonstrated that 4-DMAA should be incorporated into the electrodes prior to serum application, which avoids interference with its sensitivity and specificity. In addition, 4-DMAA oxidizes at a low anodic potential, and the oxidation peak is useful for detecting proteins in biological fluids. In summary, we have successfully demonstrated the broad application of 4-DMAA as a general indicator for the specific diagnosis of four infectious diseases in electrochemical immunosensors. Such a strategy is quite advantageous for indirect detection of proteins that lack electrochemical activities or are spatially inaccessible on the electrode surface. This new indicator opens a new avenue for monitoring biological recognition, especially for immunosensors.

Η ΠΕΡΙΛΗΨΗ ΒΡΙΣΚΕΤΑΙ ΜΕΣΑ ΣΤΟ ΑΡΧΕΙΟ PDF

Purpose: To describe a patient with an amelanotic choroidal melanoma, originally misdiagnosed as a choroidal granuloma, following his systemic diagnosis of tattoo-associated sarcoidosis. Observations: The amelanotic choroidal tumor, suspected to be a granuloma, failed initial steroid treatment. Full-thickness chorioretinal biopsy demonstrated histologic presence of uveal melanoma and tumor genetics via GEP analysis demonstrated a PRAME negative, Class 1A lesion. The amelanotic choroidal melanoma was treated successfully with I-125 plaque brachytherapy. Conclusion and importance: Despite a systemic diagnosis which predisposes a patient to uveal granuloma, amelanotic choroidal melanomas can still occur and should be considered. The association of uveal melanoma and sarcoidosis remains rare and of unclear significance.

Neste trabalho investigou-se a eficiência computacional na solução do problema de equilíbrio termodinâmico sólido-líquido (ESL) em óeos parafínicos. Foram avaliados diversos modelos termodinâmicos para a fase líquida: a equação de estado de Peng-Robinson (PR-EOS) e os modelos de coeficiente de atividade Wilson preditivo, UNIversal QUAsi Chemical (UNIQUAC) preditivo e UNIQUAC Functional-group Activity Coefficient (UNIFAC), além do modelo de solução ideal. A fase sólida é caracterizada pelo modelo multi sólido e a previsão de formação de fase sólida é inicialmente avaliada por um teste de estabilidade termodinâmica. Posteriormente, o sistema de equações não-lineares (SENL) formado pelas equações de equilíbrio termodinâmico e de balanço material é resolvido pelo método de Newton multivariável. Até onde pudemos verificar, não há estudos sistemáticos sobre o efeito do tipo de modelo (e sua complexidade) no tempo de computação necessário para a solução do problema. Por outro lado, tendo em conta o elevado número de componentes nas frações de petróleo estudadas, aspectos como a robustez (frente a diferentes estimativas iniciais) e tempo de computação são aspectos importantes neste contexto e que foram analisados neste trabalho.

We consider some optimal control problems for systems governed by linear parabolic PDEs with local controls that can move along the domain region Ω of the plane. We prove the existence of optimal paths and also deduce the first order necessary optimality conditions, using the Dubovitskii–Milyutin’s formalism, which leads to an iterative algorithm of the fixed-point kind. This problem may be considered as a model for the control of a mosquito population existing in a given region by using moving insecticide spreading devices. In this situation, an optimal control is any trajectory or path that must follow such spreading device in order to reduce the population as much as possible with a reasonable not too expensive strategy. We illustrate our results by presenting some numerical experiments.

Glyphosate detection and quantification is still a challenge. After an extensive review of the literature, we observed that Fourier transform infrared spectroscopy (FTIR) had practically not yet been used for detection or quantification. The interaction between zinc oxide (ZnO), silver oxide (Ag2O), and Ag-doped ZnO nanocrystals (NCs), as well as that between nanocomposite (Ag-doped ZnO/AgO) and glyphosate was analyzed with FTIR to determine whether nanomaterials could be used as signal enhancers for glyphosates. The results were further supported with the use of atomic force microscopy (AFM) imaging. The glyphosate commercial solutions were intensified 10,000 times when incorporated the ZnO NCs. However, strong chemical interactions between Ag and glyphosate may suppress signaling, making FTIR identification difficult. In short, we have shown for the first time that ZnO NCs are exciting tools with the potential to be used as signal amplifiers of glyphosate, the use of which may be explored in terms of the detection of other molecules based on nanocrystal affinity.

The lack of measurement of precipitation in large areas using fine-resolution data is a limitation in water management, particularly in developing countries. However, Version 6 of the Integrated Multi-satellitE Retrievals for GPM (IMERG) has provided a new source of precipitation information with high spatial and temporal resolution. In this study, the performance of the GPM products (Final run) in the state of Paraná, located in the southern region of Brazil, from June 2000 to December 2018 was evaluated. The daily and monthly products of IMERG were compared to the gauge data spatially distributed across the study area. Quantitative and qualitative metrics were used to analyze the performance of IMERG products to detect precipitation events and anomalies. In general, the products performed positively in the estimation of monthly rainfall events, both in volume and spatial distribution, and demonstrated limited performance for daily events and anomalies, mainly in mountainous regions (coast and southwest). This may be related to the orographic rainfall in these regions, associating the intensity of the rain, and the topography. IMERG products can be considered as a source of precipitation data, especially on a monthly scale. Product calibrations are suggested for use on a daily scale and for time-series analysis.

In this article we prove the existence of positive solutions of nonlinear singular biharmonic elliptic systems in smooth bounded domains, with coupling of the equations, under Navier boundary condition. Under some suitable assumptions on the nonlinearity, we prove a uniqueness result. The existence result is based on the Schauder's fixed point theorem.

In this paper, new analytical formalisms to evaluate the packet throughput of multiservice multirate slotted ALOHA optical code-division multiple-access (OCDMA) networks are proposed. The proposed formalisms can be successfully applied to 1-D and 2-D OCDMA networks with any number of user classes in the system. The bit error rate (BER) and packet correct probability expressions are derived, considering the multiple-access interference as binomially distributed. Packet throughput expressions, on the other hand, are derived considering Poisson, binomial, and Markov chain approaches for the composite packet arrivals distributions, with the latter defined as benchmark. A throughput performance evaluation is carried out for two distinct user code sequences separately, namely, 1-D and 2-D multiweight multilength optical orthogonal code (MWML-OOC). Numerical results show that the Poisson approach underestimates the throughput performance in unacceptable levels and incorrectly predicts the number of successfully received packets for most offered load values even in favorable conditions, such as for the 2-D MWML-OOC OCDMA network with a considerably large number of simultaneous users. On the other hand, the binomial approach proved to be more straightforward, computationally more efficient, and just as accurate as the Markov chain approach.

This paper investigates for the first time how the implementation of semiconductor optical amplifier (SOA)-based devices in photonic networks can negatively impact the integrity of two-dimensional wavelength-hopping time-spreading (2D-WH/TS) optical code-division multiple access (OCDMA) codes based on multi-wavelength picosecond code carriers. It is demonstrated and confirmed by simulations that the influence of an SOA under driving currents of 50 mA to 250 mA causes a 0.08 to 0.8 nm multi-wavelength picosecond code carriers’ wavelength redshift. The results obtained are then used to calculate the degradation of OCDMA system performance in terms of the probability of error Pe and the decrease in the number of simultaneous users. It is shown that, when the SOA-induced 0.8 nm code carriers redshift becomes equal to the code carries wavelength channel spacing, the (8,53)-OCDMA system performs only as a (7,53)-OCDMA system, and the number of simultaneous users drops from 14 to 10 or 84 to 74 with the forward error correction (FEC) Pe of 10−9, respectively. The impact of the 0.8 nm redshift is then shown on a (4,53)-OCDMA system, where it causes a drop in the number of simultaneous users from 4 to 3 or 37 to 24 with the FEC Pe of 10−9, respectively.

This paper deals with the identification of two-time scale linear dynamic systems, which are an important class of multiscale systems. Classical identification processes may fail to yield accurate parameters for systems of this class and, for this reason, the authors propose two different techniques to estimate the system parameters. The first technique utilizes two prefilters that are iteratively tuned. The second one considers wavelet filters that are tuned based on the results of the first iterative algorithm. Identification and analysis results for a dynamical aircraft model are shown to demonstrate the algorithm’s performance.

Thyroid dysfunctions can increase the risk of myocardial ischemia and infarction. However, the repercussions on cardiac ischemia/reperfusion (IR) injury remain unclear so far. We report here the effects of hypothyroidism and thyrotoxicosis in the susceptibility to IR injury in isolated rat hearts compared to euthyroid condition and the potential role of antioxidant enzymes.Hypothyroidism and thyrotoxicosis were induced by administration of methimazole (MMZ, 300 mg/L) and thyroxine (T4, 12 mg/L), respectively in drinking water for 35 days. Isolated hearts were submitted to IR and evaluated for mechanical dysfunctions and infarct size. Superoxide dismutase types 1 and 2 (SOD1 and SOD2), glutathione peroxidase types 1 and 3 (GPX 1 and GPX3) and catalase mRNA levels were assessed by quantitative RT-PCR to investigate the potential role of antioxidant enzymes.Thyrotoxicosis elicited cardiac hypertrophy and increased baseline mechanical performance, including increased left ventricle (LV) systolic pressure, LV developed pressure and derivatives of pressure (dP/dt), whereas in hypothyroid hearts exhibited decreased dP/dt. Post-ischemic recovery of LV end-diastolic pressure (LVEDP), LVDP and dP/dt was impaired in thyrotoxic rat hearts, whereas hypothyroid hearts exhibited improved LVEDP and decreased infarct size. Catalase expression was decreased by thyrotoxicosis.Thyrotoxicosis was correlated, at least in part, to cardiac remodeling and increased susceptibility to IR injury possibly due to down-regulation of antioxidant enzymes, whereas hypothyroid hearts were less vulnerable to IR injury.