Energy from Canada\u27s Frontier: A Fading Dream?

By the end of the present century, oil and gas from Canada\u27s frontier should comprise a substantial proportion of our total energy supply. The economic activity generated by the huge capital investments required to utilize these resources should have done much to improve Canada\u27s economy. However, whether these desirable goals will, in fact, be achieved is still very much an open question. Ordinarily, the fundamental uncertainty in dealing with oil and gas concerns whether or not these elusive substances actually exist in the area being searched. In the case of frontier oil and gas, however, the real question is not so much whether the hydrocarbons themselves exist, but whether there is a national will to harness these resources

Estudo do efeito da hidroxiureia e da Vitamina C em eritrócitos normais, submetidos a estresse oxidativo

Orientador : Prof. Dr. Aguinaldo José do NascimentoOrientadora : Profª. Drª. Maria Suely Soares LeonartDissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências da Saúde, Programa de Pós-Graduação em Ciências Farmacêuticas. Defesa: Curitiba, 19/03/2014Inclui referênciasÁrea de concentração: Análises clínicasResumo: Os eritrócitos são células altamente especializadas, continuamente expostas ao estresse oxidativo. No eritrócito humano maduro, o estresse oxidativo leva à formação de meta-hemoglobina (meta-Hb) que, por sua vez, aumenta a produção de espécies reativas de oxigênio (ERO), ocasionando mudanças no citoesqueleto da membrana eritrocitária e hemólise. A compreensão dos mecanismos que levam ao estresse oxidativo tem esclarecido muitos dos processos que levam à lesão e morte celular. O presente estudo teve como objetivo avaliar a ação da vitamina C e da hidroxiureia (HU) no metabolismo oxidativo de eritrócitos normais expostos a agentes oxidantes, in vitro. Foram obtidas amostras de sangue de 24 indivíduos considerados normais, selecionados entre estudantes e servidores da Universidade Federal do Paraná (UFPR), conforme aprovação do Comitê de Ética em Pesquisa do Setor de Ciências da Saúde da UFPR. Os eritrócitos foram incubados com vitamina C ou HU e, posteriormente, com os agentes oxidantes terc-butilhidroperóxido (t-BHP) ou 2,2'azobis (2-metil-propionamidina) dihidrocloro (AAPH). Foram realizadas determinações de concentrações de glutationa reduzida (GSH), meta-Hb, ERO, substâncias reativas ao ácido tiobarbitúrico (TBARS), porcentagens de hemólise e atividades da enzima glicose 6-fosfato desidrogenase (G6-PD) no estado basal e após ação dos agentes oxidantes, com ou sem proteção pela vitamina C ou HU. Houve diminuição nos níveis basais de GSH de 96% em amostras incubadas com t-BHP, 1 mmol/l (de 6,8 ± 1,4 para 0,3 ± 0,1 ?moles/g Hb), sem influência de incubação prévia com vitamina C ou HU. Observou-se aumento de cerca de 3 vezes na formação de meta-Hb em amostras incubadas com t-BHP, 2 mmoles/l (de 2,8 ± 0,3 para 9,1 ± 2,5%), sem influência de incubação prévia com vitamina C ou HU. A formação de ERO basal (1535 ± 522 UF/g Hb) aumentou aproximadamente 30 vezes em amostras incubadas com t-BHP, 175 ?moles/l (42716 ± 13608 UF/g Hb), observando-se proteção com aumento de apenas 9 e 10 vezes, quando se incubou previamente com vitamina C, 50 ?moles/l (13122 ± 5617 UF/g Hb) e HU, 2 mmoles/l (16025 ± 6008 UF/g Hb),respectivamente.Houve aumento na formação de TBARS de aproximadamente 3 vezes em amostras incubadas com t-BHP, 2 mmoles/l (de 56,7 ± 15,6 para 167,0 ± 52,7 nmoles/g Hb) e, respectivamente, de 1,2 e 1,5 vezes em amostras previamente tratadas com vitamina C, 10 mmoles/l (69,1 ± 18,3 nmoles/g Hb) e HU, 1 mmol/l (85,7 ± 27,6 nmoles/g Hb). A porcentagem de hemólise aumentou de 7 para 86,6% em eritrócitos normais incubados com AAPH, 200 mmoles/l, e para 8,8 e 33,9%, quando previamente incubadas com vitamina C, 10 mmoles/ e HU, 1 mmol/l, respectivamente. Houve diminuição da atividade de G6-PD de 63% nas amostras tratadas com t-BHP, 5 mmoles/l (de 7,0 ± 0,9 para 2,6 ± 0,8 UI/g Hb) e cerca de 58 e 42% nas amostras tratadas com vitamina C, 10 mmoles/l (2,9 ± 0,6 UI/g Hb) e HU, 1 mmol/l (4,1 ± 0,6 UI/g Hb), respectivamente. Foi observado que vitamina C e HU, nas concentrações testadas, possuem capacidade de prevenir parcialmente danos oxidativos induzidos in vitro, observados principalmente pela formação de TBARS e ERO e pelas porcentagens de hemólise. A partir dos resultados obtidos, sugere-se que o uso terapêutico de vitamina C ou de HU pode se correlacionar com menor estresse oxidativo e melhora na defesa antioxidante.Abstract: Red blood cells are highly specialized cells continuously exposed to oxidative stress. In mature human erythrocyte the oxidative stress leads to formation of methemoglobin (metHb) which, in turn, increases the production of reactive oxygen species (ROS), causing changes in erythrocyte membrane cytoskeleton and hemolysis. Knowledge of the mechanisms that lead to oxidative stress has clarified many of the processes that cause injury and cell death. The aim of this study was to evaluate the action of vitamin C and hydroxyurea (HU) in the oxidative metabolism of normal erythrocytes exposed to oxidizing agents in vitro. Blood samples were obtained from 24 individuals considered normal, selected among students and servers of Universidade Federal do Paraná (UFPR). Red blood cells were incubated with vitamin C or HU and subsequently with the oxidizing agents tert-butylhydroperoxide (tBHP) or 2,2?azobis (2-methylpropionamidine) dihydrochloride (AAPH). Concentrations of reduced glutathione (GSH), metHb, ROS, thiobarbituric acid reactive substances (TBARS), percentages of hemolysis, and activities of the enzyme glucose 6-phosphate dehydrogenase (G6-PD) in the basal state and after oxidizing agent actions, with or without the protection action of vitamin C or HU were determined. There was decrease in basal levels of GSH up to 96% in samples incubated with tBHP, 1 mmol/l (6.8 ± 1.4 to 0.3 ± 0.1 ?mol/g Hb), without influence of prior incubation with vitamin C or HU. It was observed an increase of about 3 times in the formation of metHb in samples incubated with tBHP, 2 mmol/l (2.8 ± 0.3 to 9.1 ± 2.5%), without influence of prior incubation with vitamin C or HU. Formation of basal ROS (1535 ± 522 FU/g Hb) was approximately 30 times higher in samples incubated with tBHP, 175 ?mol/l (42716 ± 13608 FU/g Hb), and; 9 and 10 times in samples incubated with vitamin C, 50 ?moles/l (13122 ± 5617 FU/g Hb) and HU, 2 mmol/l (16025 ± 6008 FU/g Hb), respectively. There was an increase in TBARS formation of approximately 3 times in samples incubated with tBHP, 2 mmol/l (56.7 ± 15.6 to 167.0 ± 52.7 nmol/g Hb), respectively, and 1.2 and 1.5 times in samples treated with vitamin C, 10 mmol/l (69.1 ± 18.3 nmol/g Hb) and HU, 1 mmol/l (85.7 ± 27.6 nmol/g Hb). The percentage of hemolysis increased from 7 to 86.6% in normal erythrocytes incubated with AAPH, 200 mmol/l, and to 8.8 and 33.9%, when treated with vitamin C, 10 mmol/ and HU, 1 mmol/l, respectively. There was decreased activity of G6-PD of 63% in samples treated with tBHP, 5 mmol/l (7.0 ± 0.9 to 2.6 ± 0.8 IU/g Hb) and about 58 and 42% in samples treated with vitamin C, 10 mmol/l (2.9 ± 0.6 IU/g Hb) and HU, 1 mmol/l (4.1 ± 0.6 IU/g Hb), respectively. It was observed that vitamin C and HU, in the concentrations tested, have ability to partially prevent oxidative damage induced in vitro, observed primarily by the TBARS and ROS formation, and the percentages of hemolysis. From the results obtained, it is suggested that the therapeutic use of vitamin C or HU could correlate with lower oxidative stress and it improves antioxidant defense

Endangered mussels as antimicrobial-resistant E. coli and other species (Enterobacteriaceae family) reservoirs

Freshwater unionoids are one of the most threatened animal groups worldwide, suffering dramatic regressions globally. The freshwater pearl mussel Margaritifera margaritifera, currently listed as critically endangered in Europe, and Potomida littoralis, listed as endangered, are both present in the River Tua basin (Portugal). The inappropriate use of antibiotics has led to the emergence and spread of resistant bacteria, recognized today as a serious public health problem. Based in the concept of “One health”, the objective of this study was to examine the antibacterial resistance rates in Escherichia coli and other Enterobacteriaceae isolates obtained from both bivalves collected in the River Tua Basin during the summer of 2018. Activity of 22 antibiotics was studied using disc diffusion (Kirby–Bauer) method. Multidrug resistant in E. coli and Enterobacteriaceae isolates was observed only from P. littoralis. Overall, results show that M. margaritifera inhabits more pristine sectors of river not subject to the development of multidrug resistance, unlike P. littoralis which, although does not tolerate high levels of contamination, is naturally found in lower stretches is subject to greater pressure and, as such, a greater probability of the appearance of multi-resistant organisms. The presence of E. coli in freshwater bivalves can represents serious public health problems once bacteria are one the most important biological contaminants in foodborne diseases. Given the conservation status of both studied species their protection against this silent/invisible enemy should be a priority, although work done with UnionidMussels fromNorthern Portugal showed that they had a great antimicrobial and antibiofilm activity.info:eu-repo/semantics/publishedVersio

Antibiotic Resistance Profile among Shiga Toxin-Producing Escherichia coli Isolated from dairy cattle.

Shiga toxin-producing Escherichia coli (STEC) are foodborne pathogens that can cause serious diseases in humans, including bloody diarrhoea and kidney failure. Ruminants, such as cattle, are considered the main reservoirs and source of STEC. Human infection can occur through contaminated food and water, or direct contact with infected animals.N/

Antibiotic resistance profile among Shiga toxin-producing Escherichia coli isolated from dairy cattle

Shiga toxin-producing Escherichia coli (STEC) are foodborne pathogens that can cause serious diseases in humans, including bloody diarrhoea and kidney failure. Ruminants, such as cattle, are considered the main reservoirs and source of STEC. Human infection can occur through contaminated food and water, or direct contact with infected animals. STEC antimicrobialresistance (AMR) is increasingly frequent in patients with serious disease. It is necessary to understand the epidemiology, the emergence, and the prevalence of AMR in STEC isolated from cattle to investigate how resistance spreads from ruminants to humans. Thus, susceptibility tests were performed on 55 STEC strains belonging to 29 serogroups. The strains were isolated from healthy dairy cattle faeces (cows and heifers) in the North of Portugal. Antibiotic susceptibility testing (AST) was performed by disc diffusion method following European Committee on Antimicrobial Susceptibility Testing (EUCAST, 2020) and Clinical and Laboratory Standards Institute (CLSI, 2020). The antibiotics used included penicillins (ampicillin; amoxicillin-clavulanic acid), cephalosporins (ceftazidime; cefotaxime; cefoxitin; cephalothin), carbapenems (imipenem; meropenem), aminoglycosides (kanamycin), phenicol (chloramphenicol), sulphonamides/ trimethoprim (trimethoprim-sulfamethoxazole), fluoroquinolones (moxifloxacin; levofloxacin) and tetracyclines (tetracycline; tigecycline). Results reveal low level of resistance among the isolates tested. However, five (9%) STEC isolates were resistant to one antibiotic, and three (5,5%) to three or more antibiotic classes (multidrug resistance-MDR). The MDR strains were resistant to trimethoprim-sulfamethoxazole, tetracycline and other antibiotics commonly used to treat gastroenteritis. Two strains MDR belonged to O91 serogroup and were founded in heifers in the same farm. O91 is an important serogroup to public health surveillance, as it is commonly associated with contamination of products from animal origin, and it has been isolated from patients with severe gastrointestinal disease. Overall, the AMR did not seem to be widely spread in STEC isolates from cattle; but serotype O91 might be of special concern as two O91-multidrug resistance profiles have been identified.This study was financially supported by: i) strategic project UIDB/AGR/04033/2020 by National Funds thought FCT; ii) project PhageSTEC (POCI-01-0145-FEDER-029628) funded by FEDER through COMPETE2020 (Programa Operacional Competitividade e Internacionalização) and by National Funds thought FCT (Fundação para a Ciência e a Tecnologia); iii) strategic project UIDB/04469/2020 unit and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by FCT under the scope of the European Regional Development Fund (Norte2020 – Programa Operacional Regional do Norte); iv) Base Funding - UIDB/00511/2020 of the Laboratory for Process Engineering, Environment, Biotechnology and Energy – LEPABE - funded by national funds through the FCT/MCTES (PIDDAC).info:eu-repo/semantics/publishedVersio

Aberrant High-Order Dependencies in Schizophrenia Resting-State Functional MRI Networks

The human brain has a complex, intricate functional architecture. While many studies primarily emphasize pairwise interactions, delving into high-order associations is crucial for a comprehensive understanding of how functional brain networks intricately interact beyond simple pairwise connections. Analyzing high-order statistics allows us to explore the nuanced and complex relationships across the brain, unraveling the heterogeneity and uncovering patterns of multilevel overlap on the psychosis continuum. Here, we employed high-order independent component analysis (ICA) plus multivariate information-theoretical metrics ($O$-information and $S$-information) to estimate high-order interaction to examine schizophrenia using resting-state fMRI. The results show that multiple brain regions networks may be altered in schizophrenia, such as temporal, subcortical, and higher-cognitive brain regions, and meanwhile, it also shows that revealed synergy gives more information than redundancy in diagnosing schizophrenia. All in all, we showed that high-order dependencies were altered in schizophrenia. Identification of these aberrant patterns will give us a new window to diagnose schizophrenia.Comment: 7 pages, 4 figures, Accepted to InfoCog@NeurIPS 2023 (https://sites.google.com/view/infocog-neurips-2023/home

SITE SELECTION OF DESALINATION PLANT IN LIBYA BY USING COMBINATIVE DISTANCE-BASED ASSESSMENT (CODAS) METHOD

Libya is one of the arid regions of the world, and it is facing a serious water supply shortage due to the increase in both population and water consumption in various sectors. Ground water is the main source of water in Libya, but it is limited and over exploited. Desalination of sea water is one of the possibilities for Libyan government to meet the problem of water shortage. Selecting the best location of desalination plant is important and a complex process because it is related to a variety of criteria. The aim of this paper is to select the best location of desalination plant in the northwestern coast of Libya. The selection of the best location was done by two main steps. The first step based on the criterion of minimizing water transportation cost, and the second step considered the influence of the external criteria on the location selection. The results of the case study show that the best location is the capital city (Tripoli) with respect to the assessment of Combinative Distance-based Assessment (CODAS) method. The sensitivity analysis was conducted to evaluate the robustness of the selected locations and it reveals that the CODAS method is stable and efficient to deal with multi-criteria decision-making problems. This study provides a suitable and useful tool for the decision makers concerning the optimum location of desalination facilities

The literacy of empathy : building a culture of care in classrooms

x, 137 leaves ; 29 cmThis study explores students’ capacity to develop a literacy of empathy, which contributes to a caring classroom culture. The primary goal of the work has been to instill the capacity for care in children, the capability of building a culture of care in the classroom and an awareness of empathy’s impact on others as a moral, life-long skill. Provoking contextual and personally relevant discussions in empathy with the class community, developing vocabulary related to emotion and an evaluation of written responses in journal form are considered. The study has been conducted in a grade four public school classroom setting. The findings indicate the potential for empathic instruction to transcend grade level and indicate the relevance for inclusion of instruction around a literacy of empathy as a reconceptualization of general classroom curriculum

Prevalence of shigatoxigenic Escherichia coli in bovine cattle: a survey in the north region of portugal

Shiga toxin-producing Escherichia coli (STEC) strains are food-borne pathogens that can be transmitted to humans through many different routes, but mainly through consumption of contaminated foods. STEC strains are characterized by the production of Shiga toxins (Stx) that are encoded by two genes stx1 and/or stx2. Each toxin can be subdivided into subtypes and, currently, there are three known subtypes for stx1 (stx1a, stx1c, and stx1d) and seven for stx2 (stx2a, stx2b, stx2c, stx2d, stx2e, stx2f, and stx2g). Others virulence factors, such the production of intimin protein, encoded by eae gene, are associated with severe outcomes of STEC-associated diseases. The most common STEC serotype implicated worldwide is E. coli O157:H7, but many other STEC strains are associated with severe human diseases. Ruminants, especially cattle, are a major reservoir for O157 and non-O157 STEC. Information on STEC prevalence in Portuguese dairy cattle is limited, so we analysed for the presence of STEC 329 faecal specimens collected from the rectum of healthy dairy cattle. The samples were collected from adults lactating cows (n=194) and from heifers (n=135) with ages among 6 to 18 months, between March and June 2019, at milk farms (n=17) in the North region of Portugal. After enrichment, in modified TSB with novobiocin, samples were analysed by real time PCR to detect the presence of stx1, stx2 and eae in accordance to ISO/TS 13136:2012(E). In addition, conventional PCR for the detection of sxt1 and stx2 gene subtypes was performed according to the guidelines of the VTEC European Union Reference Laboratory. A total of 139 isolates were recovered from 108 positive animals (dairy cows and heifers). The STEC prevalence was significantly higher in heifers (68/135; 50.4%) than in adult cows (40/194; 20.6%) (p < 0.05, Fisher exact test statistic value is <0.00001). STEC harbouring only stx2 (67/139; 48.2%) were the most common strains, followed by both genes stx1 and stx2 (40/139, 28.8%) and stx1 (32/139, 23%). Of the 139 STEC isolates, 35.3% have also the eae gene. Subtyping of stx1 (72) showed that stx1a was the most prevalent (100%), followed by stx1c (88.9%) and stx1d (6.9%). Stx1a and stx1c subtypes occurred alone or combination with other subtypes. However, subtype stx1d was only found in combination with subtype stx1a and or stx1c. Concerning strains with stx2 (107), the stx2a subtype was the most common and was found in 84.1% of the isolates, followed by stx2d (76.6%), stx2c (74.8%), stx2g (23.4%), stx2b (4.7%), stx2e (3.7%) and stx2f (0.9%). No strains carried stx2b or stx2f alone. For isolates carrying stx1 and stx2 simultaneously, combinations of subtypes stx1a, stx1c, stx2a, stx2c and stx2d were the most common. Furthermore, in 42 isolates (30.2%) 4 or more stx subtypes were detected simultaneously. These results show that STEC prevalence in dairy cattle is high, and that most isolates present a diverse combination of Shiga-toxin genes. Future strategies are needed to mitigate the presence of STEC in cattle and then reduce the possible contamination of food and, thus, humans.Project PhageSTEC (POCI-01-0145-FEDER-029628) funded by FEDER through COMPETE2020 (Programa Operacional Competitividade e Internacionalização) and by National Funds thought FCT (Fundação para a Ciência e a Tecnologia).info:eu-repo/semantics/publishedVersio