Ultra-low temperature structure determination of a Mn12 single-molecule magnet and the interplay between lattice solvent and structural disorder

We have determined the ultra-low temperature crystal structure of the archetypal single-molecule magnet (SMM) [Mn12O12(O2CMe)16(H2O)4]·4H2O·2MeCO2H (1) at 2 K, by using a combination of single-crystal X-ray and single-crystal neutron diffraction. This is the first structural study of any SMM in the same temperature regime where slow magnetic relaxation occurs. We reveal an additional hydrogen bonding interaction between the {Mn12} cluster and its solvent of crystallisation, which shows how the lattice solvent transmits disorder to the acetate ligands in the {Mn12} complex. Unusual quantum properties observed in 1 have long been attributed to disorder. Hence, we studied the desolvation products of 1, in order to understand precisely the influence of lattice solvent on the structure of the cluster. We present two new axially symmetric structures corresponding to different levels of desolvation of 1, [Mn12O12(O2CMe)16(H2O)4]·4H2O (2) and [Mn12O12(O2CMe)16(H2O)4] (3). In 2, removal of acetic acid of crystallisation largely resolves positional disorder in the affected acetate ligands, whereas removal of lattice water molecules further resolves the acetate ligand disorder in 3. Due to the absence of acetic acid of crystallisation, both 2 and 3 have true, unbroken S4 symmetry, showing for the first time that it is possible to prepare fully axial Mn12–acetate analogues from 1, via single-crystal to single-crystal transformations

Acute liver transplantation in a 41-year-old male patient presenting symptoms of adult-onset Still's disease

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Pellet-count sampling based on spatial distribution : a case study of the European hare in Patagonia

Las estimaciones de densidad y uso del hábitat a través del conteo de heces se hacen asumiendo una distribución al azar. Presentamos datos de liebre europea (Lepus capensis) en el noroeste de Patagonia que muestran que el patrón de distribución de sus heces se ajusta a una distribución agrupada (binomial negativa), y estimamos tamaños mínimos de muestra y varianzas basadas en este modelo. Los tamaños mininos de muestra fueron mayores y las varianzas menores que los basados en un modelo de disposición al azar. Hacernos recomendaciones para mejorar el método de conteo de heces y métodos similares cuando se puede determinar el patrón de distribución espacial de los individuos a través de un muestreo piloto.Estimates of density arad habitat use based on fecal-pellet counts have been done in the past assuming a random distribution. We present data on European hares (Lepus capensis) in northwest Patagonia showing that the distribution pattern of their pellets fats ara aggregated, negative binomial model. We also estimated minimum sample sizes arad variances based on this model. Minimum sample sizes were larger and variances were smaller than those based on a random distribution model. We provide recommendations to improve the pellet-count and similar sampling methods when the spatial distribution of the individuals can be determined through a pilot study

Cobalamin deficiency resulting in a rare haematological disorder: a case report

INTRODUCTION: We present the case of a patient with a cobalamin deficiency resulting in pancytopaenia, emphasizing the importance to define, diagnose and treat cobalamin deficiency. CASE PRESENTATION: A 52-year-old man from the Democratic Republic of Congo presented to the emergency department with shortness of breath and a sore tongue. Physical examination was unremarkable. His haemoglobin was low and the peripheral blood smear revealed pancytopaenia with a thrombotic microangiopathy. The findings were low cobalamin and folate levels, and high homocysteine and methylmalonate levels. Pernicious anaemia with chronic atrophic gastritis was confirmed by gastric biopsy and positive antiparietal cell and anti-intrinsic factor antibodies. Cobalamin with added folate was given. Six months later, the patient was asymptomatic. CONCLUSION: Cobalamin deficiency should always be ruled out in a patient with pancytopaenia. Our case report highlights a life-threatening cobalamin deficiency completely reversible after treatment

Vegan diets : practical advice for athletes and exercisers.

With the growth of social media as a platform to share information, veganism is becoming more visible, and could be becoming more accepted in sports and in the health and fitness industry. However, to date, there appears to be a lack of literature that discusses how to manage vegan diets for athletic purposes. This article attempted to review literature in order to provide recommendations for how to construct a vegan diet for athletes and exercisers. While little data could be found in the sports nutrition literature specifically, it was revealed elsewhere that veganism creates challenges that need to be accounted for when designing a nutritious diet. This included the sufficiency of energy and protein; the adequacy of vitamin B12, iron, zinc, calcium, iodine and vitamin D; and the lack of the long-chain n-3 fatty acids EPA and DHA in most plant-based sources. However, via the strategic management of food and appropriate supplementation, it is the contention of this article that a nutritive vegan diet can be designed to achieve the dietary needs of most athletes satisfactorily. Further, it was suggested here that creatine and β-alanine supplementation might be of particular use to vegan athletes, owing to vegetarian diets promoting lower muscle creatine and lower muscle carnosine levels in consumers. Empirical research is needed to examine the effects of vegan diets in athletic populations however, especially if this movement grows in popularity, to ensure that the health and performance of athletic vegans is optimised in accordance with developments in sports nutrition knowledge

Geriatrics & e-Technology: a personalized follow-up of elderly residents in nursing homes to anticipate the decompensation of geriatric syndromes. Rationale for a first prospective study Ger-e-Tech

The objective of the GER-e-TEC project is to provide recorded personalized medical monitoring of residents in nursing homes using an intelligent telemedicine platform. It will assist healthcare staff by automatically processing the information from sensors and questionnaires to provide early detection and escalate alerts to enable health professionals, operating in retirement homes, to optimize patient care

Telemedicine and Dermatology in the elderly in France: inventory of experiments

Telemedicine is now in vogue, allowing thanks to the computer and communication tools to be deployed in the field of health, such as Dermatology, areas in which it has shown interest. As the population is aging, Geriatrics is more and more concerned by this innovative practice and nursing homes are more and more concerned. We take a look at telemedicine projects in France deployed in the field of dermatology in the elderly

Kinetics of the Regeneration by Iodide of Dye Sensitizers Adsorbed on Mesoporous Titania

Regeneration of dye sensitizer molecules by reducing species contained in the electrolyte is a key mechanism in liquid dye-sensitized solar cells because it competes kinetically with a detrimental charge recombination process. Kinetics of the reduction by iodide ions of the oxidized states (S+) of two RuII complex dyes and four organic π-conjugated bridged donor−acceptor sensitizers were examined as a function of the electrolyte concentration. Results show that two different cases can be distinguished. A sublinear behavior of the regeneration rate and a plateau value reached at high bulk iodide concentrations were found for N820 ruthenium dye and interpreted as being due to an associative interaction involving the formation of (S+, I−)···I− surface complexes prior to the reaction. On the other hand, feeble reaction rates at low electrolyte concentrations and a superlinear behavior are observed predominantly for the organic dyes, pointing to a repulsive interaction between the dyed surface and iodide anions. At higher iodide bulk concentration, a linear behavior is reached, providing an estimate of a second-order rate constant. A correlation of these two opposite behaviors with the structure of the dye is observed, emphasizing the role of sulfur atoms in the association of I− anions in the dye-sensitized layer. These findings allow for a better understanding of the dye−electrolyte interaction and of the effect of the iodide concentration on the photovoltaic performances of dye-sensitized solar cells