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Objetivo: Estudo da prevalencia das fraturas do terco proximal do femur em pacientes idosos, internados em um hospital de urgencia e emergencia

In recent years, the technology readiness level of next generation lithium sulfur Li S batteries has shifted from coin cell to pouch cell dimensions. Promising optimizations of the electrodes, electrolytes, active materials, and additives lead to improved performance and cycling stability. However, new challenges arise with the pouch cell design and engineering including electrode stacking and electrolyte filling , which influence the mechanistic processes of the cell. This study presents an unprecedented multimodal operando investigation of Li S batteries on a pouch cell level and provides an inside view of material transformations during battery cycling, using X ray radiography, electrochemical impedance spectroscopy, and spatially resolved temperature monitoring. With the comparison of two different electrolytes, new experimental details about sulfur and lithium sulfide deposition and dissolution processes are revealed and related to electrolyte and temperature distribution. Operando impedance measurements on monolayer pouch cells yield a clear correlation of electrochemical and macroscopic radiographic observations. Understanding the monolayer cells behavior represents an optimal foundation for further studies on multilayer pouch cell prototypes and demonstrators with the developed operando setup. Herein the proof of principle for correlated measurement methods on pouch cell level is shown, and the experimental proof of concept for sulfur crystal suppression in sparingly solvating electrolyte is visualized

Transition metal carbodiimides MNCN (M = Co, Ni, Co0.9Ni0.1, Mn and Cu), were studied by simultaneous operando Raman and X-ray absorption spectroscopy (XAS) with focus on surface oxide detection during electrocatalytic water oxidation. As a proof of concept, easily modifiable screen-printed electrodes were used in this unified operando synchrotron setup for a trade-off between convenience of electrochemical anodization and spectroscopic data acquisition. Monitoring of chemical and structural transformations at the electrode surface during initial anodic electrode polarization shows stability for MNCN with M = Co, Ni, Co0.9Ni0.1 and Mn. While MnNCN is inactive, CoNCN emerges as the most active representative of the series. CuNCN displays pronounced side reactions and the formation of a surface copper oxide layer leading to lower current density attributed to water oxidation, as evident from an irreversible variation of the CuNCN redox behaviour in rotating ring-disc voltammetry. Furthermore, the accompanying structural and vibrational spectroscopy properties of the different MNCN compounds were explored with complementary ex situ analytical methods.

Lithium/sulfur (Li/S) batteries have a fivefold higher theoretical gravimetric energy density (2680 Wh/kg) than state-of-the-art lithium-ion batteries [1]. Furthermore, the abundance and environmental friendliness of sulfur qualify this system as a promising candidate for the post-lithium-ion era. However, the strong capacity fading with increasing cycle number is still a major obstacle to a broad technical utilization despite decades of research. Operando techniques [2] are very suitable tools to gain a mechanistic understanding of degradation processes. Especially the simultaneous combination of several independent measurements (multidimensional) while the Li/S cell is in operation allows deep insights into the degradation mechanisms and provides a further mechanistic understanding of the complex Li/S chemistry. Here we present results where up to five independent measurements are simultaneously performed with one setup (see image). Electrochemical impedance spectroscopy (EIS), UV-vis spectroscopy, temperature measurement, and X-ray imaging [3,4] or neutron small-angle scattering [5] were performed over several cycles while the cell was galvanostatically or potentiostatically charged and discharged. Structural changes on the macroscopic and microscopic scale can be correlated to characteristic signals in the EIS, charge-discharge curve, and UV-vis spectroscopy. The first part of the presentation focuses on X-ray imaging studies [3,4] that allow for valuable insights into operating Li/S cells. This method is a suitable tool for the investigation of the formation/dissolution processes of the charge product sulfur. The correlation of image analysis and impedance spectra enables a better mechanistic understanding of this system. Major observations are the formation of macroscopic alpha and beta-sulfur crystals, the formation of non-wetted cathode areas, and voltage-dependent electrolyte movement within the Li/S cell. The second part of the presentation deals with the formation and dissolution process of the discharge product, lithium sulfide. Here operando small-angle neutron scattering (SANS) is the weapon of choice to monitor nanoscopic lithium sulfide particles [5]. The SANS curves are correlated to the distribution of relaxation times calculated from impedance spectra. Furthermore, SANS gives information about the position of sulfur aggregation. In an ether-based electrolyte, neither lithium sulfide nor sulfur precipitate in the micropores. The last part of this presentation will give an outlook over the next experiments and discusses open questions in this field. References: [1] X. Fan, W. Sun, F. Meng, A. Xing, J. Liu, Advanced chemical strategies for lithium-sulfur batteries: A review, Green Energy Environ. 3 (2017) 2–19. https://doi.org/10.1016/j.gee.2017.08.002. [2] J. Tan, D. Liu, X. Xu, L. Mai, In situ/operando characterization techniques for rechargeable lithium-sulfur batteries: A review, Nanoscale. (2017) 19001–19016. https://doi.org/10.1039/C7NR06819K. [3] S. Risse, C.J. Jafta, Y. Yang, N. Kardjilov, A. Hilger, I. Manke, M. Ballauff, Multidimensional operando analysis of macroscopic structure evolution in lithium sulfur cells by X-ray radiography, Phys. Chem. Chem. Phys. 18 (2016) 10630–10636. https://doi.org/10.1039/C6CP01020B. [4] Y. Yang, S. Risse, S. Mei, C.J. Jafta, Y. Lu, C. Stöcklein, N. Kardjilov, I. Manke, J. Gong, Z. Kochovski, M. Ballauff, Binder-free carbon monolith cathode material for operando investigation of high performance lithium-sulfur batteries with X-ray radiography, Energy Storage Mater. 9 (2017) 96–104. https://doi.org/10.1016/j.ensm.2017.06.008. [5] S. Risse, E. Härk, B. Kent, M. Ballauff, Operando Analysis of a Lithium/Sulfur Battery by Small-Angle Neutron Scattering, ACS Nano. (2019) acsnano.9b03453. https://doi.org/10.1021/acsnano.9b03453. Figure 1

Great deal of studies have been focused on the energy conversion and storage devices [1,2]. Among them, lithium/sulfur battery (Li/S) with the high gravimetric energy density (~730.0 Wh/kg) and affordability (sulfur is an earth-abundant element) [1]. Targeted research could promote the commercialization of Li-S batteries in a more efficient way and keep up with challenges for building continual batteries in terms of performance and energy density, which are greatly influenced by the multi-phase interfacial reactions, polysulfide equilibria and shuttling as well as by the electrolyte decomposition under the operating conditions [1,2]. In presentation, we will present recent work on Li/S batteries in two parts: First part is related to studies of the carbonaceous materials used as cathodes in these systems. The well-tailored carbons as the sulfur hosts in Li/S batteries could be used to prevent low sulfur utilization, therefore the model-free analysis by small-angle x-ray scattering in order to obtain reliable data on the internal surface area and the average pore size will be discussed [3]. The morphological and porous features of carbons can be extremely modified when they are processed in real electrochemical conditions. Thus, in a second part we will present the simultaneous performance of several independent techniques: small-angle neutron scattering (SANS) (heatmap of the Li/S during the galvanostatic cycling), electrochemical impedance spectroscopy (EIS), galvanostatic/potentsiostatic cycling of the Li/S test cell [4]. A nanoporous and binder-free carbon electrode was applied as a model electrode for further in situ/operando analysis, which is deemed of great importance for mechanism study of batteries. The structural characterization of the nanocarbons is a crucial step towards better understanding the elucidation of structure-property-relationships which in turn will shed light on the processes occurring in complex in Li/S battery systems and helps to design cost-effective, safe batteries with preferably high capacities and longer lifetime over many cycles. A key structural features of nanocarbons and operando Li/S analysis will be the subjects of a presentation. Results obtained by in situ/operando SAS techniques are scientifically interesting and technologically very relevant for electrochemical applications. [1] G. Li, Z. Chen, J. Lu, Chem 4, 2018, 3–7. [2] A. El Kharbachi, O. Zavorotynska, M. Latroche, F. Cuevas, V. Yartys, M. Fichtner, Journal of Alloys and Compounds 817 (2020) 153261. [3] E. Härk, A. Petzold, G. Goerigk, S. Risse, I. Tallo, R. Härmas, E. Lust, M. Ballauff. Carbon 146 (2019) 284-292. [4] S. Risse, E. Härk, B. Kent, M. Ballauff, ACS Nano 13 (9) (2019) 10233-10241. Figure 1

RESUMO O processo de cura das matrizes cimentícias é muito importante na determinação das suas propriedades no estado endurecido. Nessas circunstâncias, o concreto pode sofrer sérias avarias quando exposto às severas variações térmicas. As baixas temperaturas de cura em que as matrizes cimentícias são expostas podem influenciar nas propriedades no estado endurecido, principalmente nas idades iniciais, prejudicando os processos de desfôrma e escoramento. Locais de frio intenso devem seguir procedimentos específicos de dosagem e aplicação de uma matriz cimentícia. Sendo assim, essa pesquisa objetivou analisar a influência da temperatura de cura no comportamento mecânico e físico de concretos em diversas temperaturas de cura, tanto nas idades inicias como nas mais avançadas. Observou-se que a diminuição na temperatura de cura proporcionou aumento de resistência em até 26% na idade de 28 dias nos concretos analisados, apesar de que apresentaram desenvolvimento lento das propriedades mecânicas nos 7 dias iniciais. Concretos com maior consumo de cimento apresentaram melhor desempenho nas idades inicias quando submetidos às temperaturas menores que 3 oC. Porém, percebeu-se que a cura em baixas temperaturas é capaz de proporcionar misturas mais íntegras em idades avançadas, visto que atingiram maior velocidade de propagação onda ultrassônica e resistência, pelo fato de ocorrer a hidratação residual do cimento. Abstract The curing process of cementitious matrices is very important in determining their properties in the hardened state. In these circumstances, concrete can suffer serious damage when exposed to severe thermal variations. The low curing temperatures in which the cementitious matrices are exposed can influence their properties in the hardened state, especially in the early ages, impairing the processes of shaping and shoring. Intense cold places must follow specific dosing procedures and application of a cementitious matrix. Thus, this research aimed to analyze the influence of curing temperature on the mechanical and physical behavior of concretes at different curing temperatures, both at the early and later ages. It was observed that the decrease in curing temperature provided an increase of resistance up to 26% at the age of 28 days in the analyzed concretes, even though they presented slow development of the mechanical properties in the initial 7 days. Concretes with higher cement consumption showed better performance in early ages when submitted to temperatures lower than 3 °C. However, it was observed that curing at low temperatures is able to provide more intact mixtures at advanced ages, since they achieved higher ultrasonic wave propagation velocity and resistance, due to the residual hydration of the cement.

Construction of {M4O4} motifs is an effective design paradigm for molecular polyoxometalate- and oxide-based water oxidation catalysts (WOCs). However, the mechanisms beneath this bioinspired design strategy remain a topic of intense debate. The two modifications of LiCoO2 with spinel-type and layer structures are exceptionally versatile model systems to explore the correlations among structure, electronic properties, and photochemical water oxidation. The electronic properties of both LiCoO2 modifications are tunable through delithiation while the basic structural frameworks are maintained. This provides a unique opportunity to assign the respective influence of structures and electronic properties on the water oxidation properties. While spinel-type LiCoO2 with {Co4O4} cubane motifs is active for photochemical water oxidation, the layered modification without cuboidal structural elements is nearly inactive. Here, we demonstrate that the water oxidation performance of both modifications can be significan...

Decompensation of epilepsy in burned patients may be caused by several factors. Burn is a classic etiology of systemic inflammatory response syndrome, and evolves into two physiological phases. The first 48h after injury corresponds to the first phase involving severe hypovolemic shock. The second phase corresponds to the hypermetabolic response to burns. Altered pharmacokinetics of anticonvulsant drugs is observed. Albumin and other plasma proteins are reduced, leading to increased free fraction of phenytoin, resulting in greater clearance and a lower total drug concentration. Associated with metabolic changes of burned patient, this fact predisposes to seizures in epileptic burned patients. The authors present the case of an epileptic 36-year-old-woman who developed recurrent seizures after a thermal injury, despite using the same medications and doses of anticonvulsant drugs of last 12 years, with controlled epilepsy.

PURPOSE: To evaluate the gene expression of KGF, TNF-alpha and IL-1 beta in skin fibroblasts and keratinocytes cultured from burned patients. METHODS: Three patients with large burns and three patients with small burns, as well as two controls, were included. The cell culture was initiated by the enzymatic method. After extraction and purification of mRNA, qPCR was used to assess the gene expression of KGF, TNF-alpha and IL-1 beta. RESULTS: The expression of KGF was increased on average 220-fold in large burns and 33.33-fold in small burns in fibroblasts, and 11.2-fold in large burns and 3.45-fold in small burns in keratinocytes compared to healthy patients (p

RESUMO: este artigo trata sobre o tema da transição entre a mathesis e o surgimento do sujeito através da inversão “copernicana” realizada por Kant durante a época moderna. Esta transição é central no livro As palavras e as coisas onde a preocupação com os objetos e seus signos, passa a ser uma preocupação a respeito do conhecimento do sujeito. Diante desse quadro, o foco principal da investigação remete ao cálculo matemático (a Análise) como o elemento metodológico que percorre ambas as fases. Este elemento metodológico é constatado tanto na época da mathesis, onde contribui para ordenar as coisas não-mensuráveis, quanto na época em que surge o sujeito, onde o cálculo contribui como um fator determinante da mudança. A conclusão mostra que a relação do homem com a natureza passa a ser de um mero leitor, a um sujeito ativo, provocador para que a natureza se mostre no que ela é.

Signal Amplification by Reversible-Exchange (SABRE) is a method of hyperpolarizing substrates by polarization transfer from para-hydrogen without hydrogenation. Here, we demonstrate that this method can be applied to hyperpolarize small amounts of all proteinogenic amino acids and some chosen peptides down to the nanomole regime and can be detected in a single scan in low-magnetic fields down to 0.25 mT (10 kHz proton frequency). An outstanding feature is that depending on the chemical state of the used catalyst and the investigated amino acid or peptide, hyperpolarized hydrogen-deuterium gas is formed, which was detected with (1)H and (2)H NMR spectroscopy at low magnetic fields of B(0) = 3.9 mT (166 kHz proton frequency) and 3.2 mT (20 kHz deuterium frequency).

This paper was written under the umbrella of Translation Studies in general and of fan translation and game translation in particular. Through the analysis of the translation into Brazilian Portguese made by fans of the game Chrono Trigger it was possible to show how fans may get results similar to those achieved by localization professionals. In order to define the object of our analysis we prioritized a cultural approach to translation following authors such as Nord (1994), Newmark (1998), Vermeer (1987) and Fish (1980). We have also used the concept of “transcreation” as employed by Mangiron and O’Hagan (2006). The selection of cultural terms from the game – despite it being a fictional universe – allowed for the investigation of aspects of those translations that highlight the clash of two or more different cultures. With that in mind, an adaptation of Venuti’s translation proposal (1995) on how to translate cultural marked texts was used, along with the translation techniques suggested by Molina and Hurtado (2002). The names of the characters in Chrono Trigger were then analyzed in the translation of two groups of fans: CBT and Ips Center.

Advances with para-hydrogen induced polarization open up new fields of applications for portable low-field NMR. Here we report the possibility of tracing drugs down to the micromolar regime. We could selectively polarize nicotine quantities similar to those found in one cigarette. Also less than 1 mg of harmine, a drug used for treatment of Parkinson's disease, and morphine extracted from an opium solution were detectable after polarization with para-hydrogen in single-scan (1)H-experiments. Moreover, we demonstrate the possibility to selectively enhance and detect the (1)H-signal of drug molecules with PHIP in proton rich standard solutions that would otherwise mask the (1)H NMR signal of the drug.