On the classification of stationary electro-vacuum black holes

We obtain a classification of stationary, $I^+$--regular, non-degenerate and analytic electro-vacuum space-times in terms of Weinstein solutions. In particular, for connected horizons, we prove uniqueness of the Kerr-Newman black holes

Analytical study of tunneling times in flat histogram Monte Carlo

We present a model for the dynamics in energy space of multicanonical simulation methods that lends itself to a rather complete analytic characterization. The dynamics is completely determined by the density of states. In the \pm J 2D spin glass the transitions between the ground state level and the first excited one control the long time dynamics. We are able to calculate the distribution of tunneling times and relate it to the equilibration time of a starting probability distribution. In this model, and possibly in any model in which entering and exiting regions with low density of states are the slowest processes in the simulations, tunneling time can be much larger (by a factor of O(N)) than the equilibration time of the probability distribution. We find that these features also hold for the energy projection of single spin flip dynamics.Comment: 7 pages, 4 figures, published in Europhysics Letters (2005

Identifying Beliefs About Smoking in Patients with Peripheral Vascular Disease

Peripheral vascular disease (PVD) is a chronic disabling illness that frequently results in the occlusion of arteries in lower limbs and may cause ischemia, gangrene, or infection. The single most significant factor contributing to both the onset and progression of PVD is smoking, which has addictive properties. Once smoking becomes a habitual behavior, combined with the atherosclerotic process, a disastrous pathway ensues. The aim of this project was to gain an understanding of the beliefs of patients with PVD who smoked. Data were obtained from a sample of participants with a known history of PVD who have had a previous vascular intervention and who are established patients in a vascular surgeon’s private office where N=50. The majority of participants were male (n=31; 63%) 65-74 years of age (n=18; 36%), were unemployed (n=30; 60%) and have smoked for greater than 51+ years (n=13; 26%). A scale that was developed guided by The Behavioral beliefs subscale revealed that PVD patients enjoyed smoking, smoking helped them to relax, and that they believed that they were addicted to smoking. Results from the normative beliefs indicated that the spouse or significant other, children or those whom they lived with, did not approve of their smoking and also that their healthcare provider had discussed smoking cessation with them. The control beliefs subscale results demonstrated that most patients had attempted to quit smoking, believed it would be a difficult behavior to stop, believed that they would require the assistance of a patch or medication and feared the withdrawal symptoms. Exploring the beliefs and thought process of patients who smoked provided a rich body of knowledge which can afford the healthcare professional with the ability to better understand the smoking experience as seen through patients’ eyes

A comprehensive study of herbal blends from portuguese smart-shops: isolation, analysis and toxicological impact

Dissertação de mestrado Erasmus Mundus para obtenção de grau de mestre em Técnicas Laboratoriais ForensesIn the last few years, several samples were found to contain different combinations of multiple synthetic cannabinoids, fact which may end up in a serious health threat since these substances are not fully studied and the toxic as well as the pharmacological effects are not known. The isolation and quantification of psychoactive substances from the herbal blends, known as ‘Spice’, was performed by HPLC-UV and the identification by LC-MS/MS. The HPLC-UV method was validated for the quantification and has proven to be fit for purpose. The sample 1 has shown the coexistence of JWH-122 (29,07mg/g) and JWH-210 (175,9mg/g) while the sample 2 was found to contain one single synthetic cannabinoid, the JWH-018 (149,7mg/g). The sample 3 presented the same multiple psychoactive substances as sample 1, JWH-122 (7,3mg/g) and JWH-210 (129,9mg/g). Since these drugs are mainly smoked, a smoking machine was created* in order to characterize the chemical composition of the pyrolysis. The GC-MS analysis performed to the pyrolysis solutions has shown no degradation of the JWH-018, drug used for the assay. The toxicity impact of the characterized substances was assessed on human neuroblastoma SH-SY5Y cells, applying a combination of multiple synthetic cannabinoids (JWH-122 and JWH-210) and single one (JWH-018). The preliminary results indicate that these psychoactive substances are not toxic to the cells in the concentrations ranging from 0μM to 50μM. *Designed by Dr. Alexandre Quintas and is under a patenting proces

It takes two flints to make a fire: Understanding work engagement at the team level

The main goal of the present thesis is to propose, validate and understand the construct of team work engagement. The thesis includes one theoretical article and five empirical articles. Theoretically, team work engagement is defined as a shared emergent state that mediates the relationship between interpersonal team processes and team effectiveness. In studies 1 and 2, we aimed at validating the construct. Our results indicate that work engagement can be empirically assessed at the individual and team levels. Moreover, the findings support the proposed mediation role of team work engagement. Study 3 was aimed at investigating a specific interpersonal team process variable, team conflict, in the relationship between team resources and team effectiveness. Results show that task and relationship conflict are contextual variables that have a negative impact on team work engagement. Task conflict, however, can strengthen the positive relationship between team work engagement and team performance. In study 4 we investigated the cross-level influence of team work engagement and individual positive emotions on perceptions of team viability. Our results indicate that team-level states have a “protective” effect on this specific outcome. Finally, study 5 takes a qualitative look at team members’ interactions, looking for patterns that characterize highly engaged teams. We found that positive affective interactions are frequent within these teams, but that the relationship between affective interactions and team objective performance is not linear. This work contributes to our understanding of teamwork, particularly its affective properties. The thesis also feeds the discussion of multilevel phenomena in organizational life, highlighting relevant clues for managing teams.A presente tese tem como objectivo propor, validar e explorar a emergência do constructo de “work engagement” de equipa. Apresenta-se uma proposta teórica, e cinco estudos empíricos. Teoricamente, define-se “work engagement” de equipa como um estado emergente partilhado, mediador da relação entre processos interpessoais de equipa e a eficácia da mesma. Os dois primeiros estudos procuraram validar o constructo. Os resultados mostram que este é distinto ao nível individual e de equipa, e suportam o referido papel mediador. O estudo 3 analisa um processo interpessoal específico, o conflito, na relação entre os recursos da equipa e a sua eficácia, mediada pelo “work engagement” de equipa. O conflito relacional e de tarefa apresentam uma relação negativa com o “work engagement” de equipa. Porém, o conflito de tarefa influencia positivamente a relação entre o “work engagement” de equipa e o seu desempenho. No estudo 4 investigou-se a influência “cross-level” entre o “work engagement” de equipa e as emoções positivas individuais para a percepção da viabilidade da equipa. Os resultados indicam que os estados colectivos têm um efeito “protector” para esta variável. Finalmente, o estudo 5 apresenta uma abordagem qualitativa, procurando padrões de interacção que caracterizam equipas de elevado “engagement”. Estas equipas demonstram frequentes interacções afectivas com valência positiva, mas a relação entre estas e a performance objectiva das equipas não é linear. Este trabalho contribui simultaneamente para a compreensão do trabalho em equipa, nomeadamente da sua dimensão afectiva, e para a discussão de constructos de natureza multinível, salientando pistas relevantes para a gestão de equipas

Ligand discovery and structural-functional analysis of proteins involved in plant cell wall degradation

The plant cell wall is constituted by recalcitrant polysaccharides with diverse sequences that comprise an abundant source of terrestrial biomass. To efficiently degrade plant cell wall polysaccharides, some cellulolytic bacterial organisms, such as Clostridium thermocellum and Ruminococcus flavefaciens, have an extracellular multi-enzyme complex with catalytic and non-catalytic carbohydrate-binding modules (CBMs). CBMs play a crucial role in enhancing the catalytic efficiency of the enzymes by proximity effect, cell attachment or targeting and disruptive function. The Carbohydrate Active enZymes database (CAZy) organizes the identified CBMs by sequence similarity into different families. Deposition of CBM sequences in the CAZy database is continually growing for which characterization and structure-function analysis is required. In this study we aim to characterize the carbohydrate ligand specificities of C. thermocellum ATCC 27405 and R. flavefaciens FD-1 CBMs assigned to different families in the CAZy database. We performed carbohydrate microarray screening analysis for ligand discovery and crystallization screenings aiming to solve the 3D structures of the CBM-ligand complexes by X-ray crystallography. To complement the information provided by these methodologies we also performed ITC (Isothermal Titration Calorimetry), MST (Microscale Thermophoresis) and affinity gel electrophoresis. With the implementation of this approach it was possible to elucidate different carbohydrate binding specificities for biotechnologically relevant CBMs. The results from the initial carbohydrate microarray screening constitute a functional start point to target CBMs for structural-functional analysis of carbohydrate-recognition. C. thermocellum family 50 (CtCBM50) reveals to be a novel chitin binding LysM domain and binding with insoluble chitin and a β-(1-4)-GlcNAc chitin oligosaccharide was identified. R. flavefaciens FD-1 family 62 CBM (RfCBM62) reveals to be highly specific for a pectic polysaccharide for which the structure is being investigated and binding to galacturonan DP4 was observed. In the scope of this thesis, and as the structural characterization was not achieved in due time, the sequence similarity to known structures inspired the attempt to computationally produce similarity models for the two CBMs. The (hypothetical) conservation of the secondary structures revealed some structural features of the proteins under study. An important outcome from this integrative study is the possibility to understand the versatility of plant and fungal saccharide sequences and their recognition by the different CBM families. The different binding patterns observed could reflect adaptive pressures of the microorganisms to their respective ecological niches, translating in divergent evolution of the proteome

Currency Museum

The metallic parasols generate shadow and urban scale.https://openscholarship.wustl.edu/bcs/1244/thumbnail.jp