From Dragondoom to Dragonstar: Side-channel Attacks and Formally Verified Implementation of WPA3 Dragonfly Handshake

It is universally acknowledged that Wi-Fi communications are important to secure. Thus, the Wi-Fi Alliance published WPA3 in 2018 with a distinctive security feature: it leverages a Password-Authenticated Key Exchange (PAKE) protocol to protect users' passwords from offline dictionary attacks. Unfortunately, soon after its release, several attacks were reported against its implementations, in response to which the protocol was updated in a best-effort manner. In this paper, we show that the proposed mitigations are not enough, especially for a complex protocol to implement even for savvy developers. Indeed, we present **Dragondoom**, a collection of side-channel vulnerabilities of varying strength allowing attackers to recover users' passwords in widely deployed Wi-Fi daemons, such as hostap in its default settings. Our findings target both password conversion methods, namely the default probabilistic hunting-and-pecking and its newly standardized deterministic alternative based on SSWU. We successfully exploit our leakage in practice through microarchitectural mechanisms, and overcome the limited spatial resolution of Flush+Reload. Our attacks outperform previous works in terms of required measurements. Then, driven by the need to end the spiral of patch-and-hack in Dragonfly implementations, we propose **Dragonstar**, an implementation of Dragonfly leveraging a formally verified implementation of the underlying mathematical operations, thereby removing all the related leakage vector. Our implementation relies on HACL*, a formally verified crypto library guaranteeing secret-independence. We design Dragonstar, so that its integration within hostap requires minimal modifications to the existing project. Our experiments show that the performance of HACL*-based hostap is comparable to OpenSSL-based, implying that Dragonstar is both efficient and proved to be leakage-free.Comment: Accepted at 2023 IEEE 8th European Symposium on Security and Privacy (EuroS&P

The 4-year Experience of Nursing Activities Score Use in a Brazilian Cardiac Intensive Care Unit

The assessment of nursing workload offers both support for patient care planning and service management. In an Intensive Care Unit (ICU) this workload is measured by the Nursing Activities Scores (NAS), although in specialized areas such as Cardiology, its use is still diminished. Objective: To describe NAS and the prevalence of its sub-items in a Brazilian Cardiac ICU. We also aimed to evaluate NAS oscillation since the opening of the unit, and according to the day of the week. Methods: Daily NAS records collected from November 2014 to October 2018 were assessed, totaling 8600 assessments distributed over 49 months. The data were analyzed according to time, day of the week, number of records per day, and dichotomizing if NAS was higher or lower than 50 points. Results: NAS presented mean value of 52.91 points and a median of 53.40 points. The mean NAS values per month ranged from 45.00 to 59.10 points. The percentage of NAS assessments above 50 points ranged from 20.59 to 92.34% per month and proved to be a better indicator for assessing the variability of the monthly workload. When combined two by two, 66.01% of NAS combinations scored more than 100 points, suggesting the need for more than one nursing professional per day. When the data were stratified by year, 2018 had the lowest means compared to the others. When compared to the mean values in function of the day of the week, it was observed that Monday to Friday (with the highest mean on Wednesday, the predominant day for cardiac surgeries) showed higher values than weekends. Conclusions: Overall, NAS showed low values compared to other general or cardiac ICUs, it also presented temporal variability and our results showed risk of workload overload which can compromise patient care and safety. Such results reinforce the importance of the administrative and assistant aspects of the routine use of NAS in ICUs specially in specialized environments as Cardiac ICU

Origin and Control of OFF-State Leakage Current in GaN-on-Si Vertical Diodes

Conventional GaN vertical devices, though promising for high-power applications, need expensive GaN substrates. Recently, low-cost GaN-on-Si vertical diodes have been demonstrated for the first time. This paper presents a systematic study to understand and control the OFF-state leakage current in the GaN-on-Si vertical diodes. Various leakage sources were investigated and separated, including leakage through the bulk drift region, passivation layer, etch sidewall, and transition layers. To suppress the leakage along the etch sidewall, an advanced edge termination technology has been developed by combining plasma treatment, tetramethylammonium hydroxide wet etching, and ion implantation. With this advanced edge termination technology, an OFF-state leakage current similar to Si, SiC, and GaN lateral devices has been achieved in the GaN-on-Si vertical diodes with over 300 V breakdown voltage and 2.9-MV/cm peak electric field. The origin of the remaining OFF-state leakage current can be explained by a combination of electron tunneling at the p-GaN/drift-layer interface and carrier hopping between dislocation traps. The low leakage current achieved in these devices demonstrates the great potential of the GaN-on-Si vertical device as a new low-cost candidate for high-performance power electronics

Estruturas de Governança e Atributos das Transações no Complexo Agroindustrial de Florestas Ribas do Rio Pardo (MS)

This work consists of evaluating how the economic agents of the agroindustrial complex of planted forests in Ribas do Rio Pardo - MS are related, in the light of the theory of institutional economics? To this end, the objectives were adopted to identify which governance structures were adopted by this agro-industrial complex, based on the attributes of the transactions, and to list their influences on local development. As a methodology, a qualitative research was carried out, with primary and secondary information, through the application of mixed semi-structured questionnaires, on-site visits and the opinion of specialists in the segment. As a result, there is a heterogeneity in the governance structures present in the complex, mainly due to the great disparity in the attributes of transactions, making local development dependent on the strongest links in the agro-industrial complex.Este trabajo consiste en evaluar cómo los agentes económicos del complejo agroindustrial de bosques plantados en Ribas do Rio Pardo - MS están relacionados, a la luz de la teoría de la economía institucional. Con este fin, se adoptaron los objetivos para identificar qué estructuras de gobernanza fueron adoptadas por este complejo agroindustrial, en función de los atributos de las transacciones, y para enumerar sus influencias en el desarrollo local. Como metodología, se realizó una investigación cualitativa, con información primaria y secundaria, mediante la aplicación de cuestionarios semiestructurados mixtos, visitas in situ y la opinión de especialistas en el segmento. Como resultado, existe una heterogeneidad en las estructuras de gobernanza presentes en el complejo, principalmente debido a la gran disparidad en los atributos de las transacciones, lo que hace que el desarrollo local dependa de los vínculos más fuertes en el complejo agroindustrial.O complexo agroindustrial de florestas de Ribas do Rio Pardo/MS apresenta boa participação na produção de florestas, tanto na região onde se localiza quanto perante ao restante do estado. Caracterizar os agentes deste complexo e suas interações com fornecedores e consumidores tornam-se relevantes quando analisadas do ponto de vista de como o fortalecimento deste complexo pode contribuir para o desenvolvimento local. Assim, este trabalho consiste em responder como os agentes econômicos do complexo agroindustrial de florestas plantadas deste município se relacionam? Para isso, foram adotados os objetivos de identificar quais as estruturas de governança adotadas por este complexo agroindustrial, com base nos atributos das transações, e elencar suas influências no desenvolvimento local. Como referencial teórico, foram utilizados os preceitos da Nova Economia Institucional, em especial a Economia dos Custos de Transação, bem como, as teorias sobre complexo industrial e sua relação com o desenvolvimento local. Como metodologia, realizou-se uma pesquisa qualitativa, com informações primárias e secundárias, através da aplicação de questionários mistos semiestruturados, visitas in loco e conversas com especialistas do segmento. Como resultado, evidencia-se uma heterogeneidade quanto às estruturas de governança presentes no complexo, devido principalmente a grande disparidade existente nos atributos das transações (frequência, incerteza e especificidade dos ativos). Os agentes que transacionam utilizando estruturas de governança mais complexas mantém uma relação de dependência fraca com o restante dos agentes, provocando um efeito punitivo para todo o complexo, pois torna o desenvolvimento local dependente dos elos mais fortes, que mantém uma baixa vinculação com o local

Clinical Data, Echocardiography and Surgical Wound Infection of Patients Undergoing Cardiac Surgery

Introduction: Due to importance of surgeries for treatment of heart diseases, it is necessary to recognize surgical site infection and other Healthcare-Related Infections as the main post-surgical complications. Objective:  To analyze the association and correlation between clinical and propaedeutic variables with the prevalence of wound infection in patients undergoing cardiac surgery  Methodology:  Quantitative, analytical study with a retrospective approach. Data collection  was performed in the Medical Archive Sector of the Clinical Hospital of Uberlandia (HCU), using a previously structured instrument. Results:  A total of 453 medical records were evaluated, mainly masculine gender (n=313; 69.1%). A time patient hospital stays had a mean of 36.47±28.7days, surgical indication of myocardial revascularization (n=278; 61.4%). The rate of surgical wound infection (SWI) found was 19%. Correlation and clinical associations were: Time of surgery and left ventricle ejection fraction (LVEF) (r=0,10; p<0,05); time hospital stay and almost all echocardiographic variables, weight and height (p=0.01); Systolic blood pressure (SBP) and left ventricle posterior wall (LVPW) (r=0.16), LVEF (r=0.12) and intraventricular septum (r=0.13), (p<0.01); Diastolic blood pressure (DBP) and left ventricle posterior wall (LVPW) (r= 0.10; p<0.01). Conclusion: The study has hight potential to increase scientific evidences and improving  cardiovascular care, cardiovascular surgery field and prevention of healthcare-associated infections

O ENSINO DE ANTROPOLOGIA NOS CURSOS DE FORMAÇÃO DE PROFESSORES DE EDUCAÇÃO FÍSICA DO MUNICÍPIO DE CANINDÉ - CEARÁ

Desde 1980, no Brasil, cresceu a importância das bases sociais e humanas na construção do conhecimento em Educação Física. Nesta perspectiva, o objetivo geral deste trabalho é analisar o ensino de Antropologia nos cursos de Licenciatura em Educação Física do município de Canindé, no Ceará. O desenvolvimento de etnografias sobre lazer, esporte e educação física, a problematização das relações entre natureza e cultura, gênero, etnia e raça, além do avanço sobre as noções de corpo compõem a agenda brasileira em torno do assunto. A metodologia aplicada nesta pesquisa deu-se a partir de revisões bibliográficas no campo da Antropologia e da Antropologia da Educação Física. Também, fizemos levantamentos documentais nas duas instituições que oferecem tal formação pedagógica, colhendo os projetos político pedagógicos dos cursos, ementário de disciplinas e materiais didáticos disponibilizados nas aulas. Foram realizadas, ainda, observações e entrevistas com alunos e professores. O reconhecimento da educação física, do esporte e do lazer como fenômenos culturais tem oferecido resistências à supremacia técnica e biologista dos currículos. Os seminários temáticos sobre autores e teorias que permeiam o campo antropológico das práticas corporais e a realização de eventos de extensão, com os educandos se envolvendo com os saberes tradicionais e comunitários do município estão entre as atividades mais valorativas. Contudo, o reduzido acervo bibliográfico disponibilizado sobre o assunto, a falta de recursos para realização de atividades extra sala de aula, a baixa carga horária das disciplinas articuladas ao tema e a formação antropológica deficitária dos professores universitários demonstram alguns problemas encontrados

MODELOS MATEMÁTICOS PARA ESTIMATIVA DE ÁREA FOLIAR DE TECA (Tectonas grandis L. f.)

Esta pesquisa, objetivou obter uma equação que, por meio de parâmetros lineares dimensionais das folhas, permita a estimativa da área foliar de Tectonas grandis L. f.. Em agosto de 2015 até setembro de 2016, foram coletados 354 limbos foliares retirados do terço mediano da copa das árvores de três tecais localizado em Capitão poço, Irituia e Garrafão do Norte, situado na microrregião do Pará. A área foliar foi determinada pelo método dos discos. Ajustaram-se modelos lineares, lineares sem intercepto, quadrático, cúbicos, logarítmicos, exponenciais e potenciais, determinadas considerando-se a área foliar real como variável dependente e o comprimento (C), a largura (L), a soma (C + L) e o produto do (C x L) de cada limbo foliar como variáveis independentes, sendo eliminados os modelos que apresentaram coeficiente de determinação menor que 0,90. A estatística utilizada para validar o desempenho dos modelos, foi o coeficiente de correlação de Pearson (r), o de determinação (R2), a raiz do quadrado médio do erro (RQME), o erro absoluto médio (EAM), o índice d de Willmott e o índice CS. Os modelos que melhor se ajustaram aos dados foram: o potencial 0,0464(C+L)2,2397, o linear sem intercepto 0,4449 (CxL), e o quadrático 0001 (CxL)2 + 0,2573 (CxL) + 98,2606. A equação linear sem intercepto considerando (CxL) foi o que apresentou o melhor desempenho para estimar a área foliar de teca (Tectonas Grandis L. f)

Burnt sugarcane harvesting: cardiovascular effects on a group of healthy workers, Brazil

Background: Brazil is the world's largest producer of sugarcane. Harvest is predominantly manual, exposing workers to health risks: intense physical exertion, heat, pollutants from sugarcane burning. Design: Panel study to evaluate the effects of burnt sugarcane harvesting on blood markers and on cardiovascular system. Methods: Twenty-eight healthy male workers, living in the countryside of Brazil were submitted to blood markers, blood pressure, heart rate variability, cardiopulmonary exercise testing, sympathetic nerve activity evaluation and forearm blood flow measures (venous occlusion plethysmography) during burnt sugarcane harvesting and four months later while they performed other activities in sugar cane culture. Results: Mean participant age was 31 +/- 6.3 years, and had worked for 9.8 +/- 8.4 years on sugarcane work. Work during the harvest period was associated with higher serum levels of Creatine Kinase - 136.5 U/L (IQR: 108.5-216.0) vs. 104.5 U/L (IQR: 77.5-170.5), (p = 0.001); plasma Malondialdehyde-7.5 +/- 1.4 mu M/dl vs. 6.9 +/- 1.0 mu M/dl, (p = 0.058); Glutathione Peroxidase - 55.1 +/- 11.8 Ug/Hb vs. 39.5 +/- 9.5 Ug/Hb, (p < 0.001); Glutathione Transferase- 3.4 +/- 1.3 Ug/Hb vs. 3.0 +/- 1.3 Ug/Hb, (p = 0.001); and 24-hour systolic blood pressure - 120.1 +/- 10.3 mmHg vs. 117.0 +/- 10.0 mmHg, (p = 0.034). In cardiopulmonary exercise testing, rest-to-peak diastolic blood pressure increased by 11.12 mmHg and 5.13 mmHg in the harvest and non-harvest period, respectively. A 10 miliseconds reduction in rMSSD and a 10 burst/min increase in sympathetic nerve activity were associated to 2.2 and 1.8 mmHg rises in systolic arterial pressure, respectively. Conclusion: Work in burnt sugarcane harvesting was associated with changes in blood markers and higher blood pressure, which may be related to autonomic imbalance

Impacts of experimentally imposed drought on leaf respiration and morphology in an Amazon rain forest

1. The Amazon region may experience increasing moisture limitation over this century. Leaf dark respiration (R) is a key component of the Amazon rain forest carbon (C) cycle, but relatively little is known about its sensitivity to drought. 2. Here, we present measurements of R standardized to 25 C and leaf morphology from different canopy heights over 5 years at a rain forest subject to a large-scale through-fall reduction (TFR) experiment, and nearby, unmodified Control forest, at the Caxiuana˜ reserve in the eastern Amazon. 3. In all five post-treatment measurement campaigns, mean R at 25 C was elevated in the TFR forest compared to the Control forest experiencing normal rainfall. After 5 years of the TFR treatment, R per unit leaf area and mass had increased by 65% and 42%, respectively, relative to pre-treatment means. In contrast, leaf area index (L) in the TFR forest was consistently lower than the Control, falling by 23% compared to the pre-treatment mean, largely because of a decline in specific leaf area (S). 4. The consistent and significant effects of the TFR treatment on R, L and S suggest that severe drought events in the Amazon, of the kind that may occur more frequently in future, could cause a substantial increase in canopy carbon dioxide emissions from this ecosystem to the atmosphere