The critical role of ultra-low-energy vibrations in the relaxation dynamics of molecular qubits.

Improving the performance of molecular qubits is a fundamental milestone towards unleashing the power of molecular magnetism in the second quantum revolution. Taming spin relaxation and decoherence due to vibrations is crucial to reach this milestone, but this is hindered by our lack of understanding on the nature of vibrations and their coupling to spins. Here we propose a synergistic approach to study a prototypical molecular qubit. It combines inelastic X-ray scattering to measure phonon dispersions along the main symmetry directions of the crystal and spin dynamics simulations based on DFT. We show that the canonical Debye picture of lattice dynamics breaks down and that intra-molecular vibrations with very-low energies of 1-2 meV are largely responsible for spin relaxation up to ambient temperature. We identify the origin of these modes, thus providing a rationale for improving spin coherence. The power and flexibility of our approach open new avenues for the investigation of magnetic molecules with the potential of removing roadblocks toward their use in quantum devices.

Unveiling phonons in a molecular qubit with four-dimensional inelastic neutron scattering and density functional theory.

Phonons are the main source of relaxation in molecular nanomagnets, and different mechanisms have been proposed in order to explain the wealth of experimental findings. However, very limited experimental investigations on phonons in these systems have been performed so far, yielding no information about their dispersions. Here we exploit state-of-the-art single-crystal inelastic neutron scattering to directly measure for the first time phonon dispersions in a prototypical molecular qubit. Both acoustic and optical branches are detected in crystals of [VO(acac)[Formula: see text]] along different directions in the reciprocal space. Using energies and polarisation vectors calculated with state-of-the-art Density Functional Theory, we reproduce important qualitative features of [VO(acac)[Formula: see text]] phonon modes, such as the presence of low-lying optical branches. Moreover, we evidence phonon anti-crossings involving acoustic and optical branches, yielding significant transfers of the spin-phonon coupling strength between the different modes.

Outcome in lacunar stroke: A cohort study.

OBJECTIVES: We evaluated a prospective cohort of 150 patients under observation in our centre for lacunar strokes. The purpose of this study was to evaluate the outcome at time of discharge and 6 months after lacunar stroke, as well as the correlation with cardiovascular risk factors and selected biochemical parameters already evaluated on admission. Focus was to identify possible prognostic factors, which might be targeted through appropriate intervention concentrating on reduction in the incidence and impact of early clinical deterioration. METHODS: 150 patients with a lacunar stroke were included in the present study. A clinical 6-month follow-up was available for 98.7% of the patients. Infarcts were classified by size, shape and location. RESULTS: The most important predictors of high NIHSS score at time of discharge resulted NIHSS on admission (P < .001), leukocytosis (P = .013), in-hospital infections (P = .016) and size of lacunae (P = .005). Similarly, the most important predictors of poor outcome 6 months later were NIHSS on admission (P = .01), leukocytosis (P = .014), elevated CRP (P = .019), in addition to pre-admission Rankin (P < .001). CONCLUSION: Although infections are not causatively related to lacunar strokes, their prompt recognition and early treatment, control of inflammatory markers and fever are most important in influencing functional outcome in lacunar stroke.

Chemotherapy-induced nausea and vomiting (CINV) in patients with advanced lung cancer during the first-line treatment: assessment by physicians, nurses, and patients from an Italian multicenter survey.

PURPOSE: Chemotherapy-induced nausea and vomiting (CINV) still represents a common side-effect of chemotherapy, and often, its perception differs between patients and healthcare professionals. The aim of this study was to evaluate the agreement on the perception of CINV and other items among clinicians, patients, and nurses. METHODS: This observational prospective study was part of an evaluation program promoted by the Women Against Lung Cancer in Europe (WALCE) Onlus. From August 2015 to February 2016, a survey was administered in 11 oncologic institutions to 188 stage IV lung cancer patients and to their oncologists and nurses during first-line chemotherapy. Our survey investigated 11 aspects: anxiety, mood, weakness, appetite, nausea, vomiting, pain, drowsiness, breath, general condition, and trust in treatments. These items were assessed through Numerical Rating Scale at four consecutive evaluations: at T0 (immediately prior to the first cycle), at T1 (immediately prior to the second cycle), at T2 (immediately prior to the third cycle), and at T3 (immediately prior to the fourth cycle). Clinician versus patient (CvP), nurse versus patient (NvP), and clinician versus nurse (CvN) agreements were estimated applying Weighted Cohen's kappa. A multivariate logistic model and generalized equation estimates were applied to evaluate factors possibly influencing CINV development. RESULTS: The incidence of patients reporting CINV varied from 40% at T0 to 71% at T3. Both CvP and NvP agreement on the investigated items were mainly moderate, slightly increasing over time, and becoming substantial for some items, in particular for NvP. Pre-chemotherapy anxiety in its mild, moderate, and severe manifestations, as well as mild, moderate, and severe anxiety experienced after chemotherapy start, exposed patients to a higher risk of anticipatory and acute/delayed CINV, respectively. CONCLUSIONS: Despite clinical staff awareness of patients' status and perceptions, CINV still represents a clinical problem. This study confirms that particular attention should be paid to anxiety due to its key role in CINV development.

Giant spin-phonon bottleneck effects in evaporable vanadyl-based molecules with long spin coherence.

Vanadium(iv) complexes have recently shown record quantum spin coherence times that in several circumstances are limited by spin-lattice relaxation. The role of the environment and vibronic properties in the low temperature dynamics is here investigated by a comparative study of the magnetization dynamics as a function of crystallite size and the steric hindrance of the ß-diketonate ligands in VO(acac)2 (1), VO(dpm)2 (2) and VO(dbm)2 (3) evaporable complexes (acac- = acetylacetonate, dpm- = dipivaloylmethanate, and dbm- = dibenzoylmethanate). A pronounced crystallite size dependence of the relaxation time is observed at unusually high temperatures (up to 40 K), which is associated with a giant spin-phonon bottleneck effect. We model this behaviour by an ad hoc force field approach derived from density functional theory calculations, which evidences a correlation of the intensity of the phenomenon with ligand dimensions and the unit cell size.

Muscular forearm activation in hand-grip tasks with superimposition of mechanical vibrations.

The purpose of this paper is to evaluate the muscular activation of the forearm, with or without vibration stimuli at different frequencies while performing a grip tasks of 45s at various level of exerted force. In 16 individuals, 9 females and 7 males, the surface electromyogram (EMG) of extensor carpi radialis longus and the flexor carpi ulnari muscles were assessed. At a short latency from onset EMG, RMS and the level of MU synchronization were assessed to evaluate the muscular adaptations. Whilst a trend of decay of EMG Median frequency (MDFd) was employed as an index of muscular fatigue. Muscular tasks consists of the grip of an instrumented handle at a force level of 20%, 30%, 40%, 60% of the maximum voluntary force. Vibration was supplied by a shaker to the hand in mono-frequential waves at 20, 30, 33 and 40Hz. In relation to EMG, RMS and MU synchronization, the muscular activation does not seem to change with the superimposition of the mechanical vibrations, on the contrary a lower MDFd was observed at 33Hz than in absence of vibration. This suggests an early muscular fatigue induced by vibration due to the fact that 33Hz is a resonance frequency for the hand-arm system.

Aggressive gastric carcinoma producing alpha-fetoprotein: a case report and review of the literature.

A 65-year-old man presented to our hospital with abdominal pain, dyspepsia and anorexia. Laboratory tests showed an altered liver function and abdomen ultrasonography revealed multiple liver nodules, suspected to be metastatic lesions. Serous tumor markers were elevated and a very high level of alpha-fetoprotein was found. Computer tomography confirmed the hepatic lesions and disclosed a thickening of the lesser curvature of the gastric wall. A subsequent endoscopy showed an ulcer on the lesser curvature. Biopsies taken from the gastric ulcer and the liver nodule revealed an adenocarcinoma, both of gastric origin. Shortly after the diagnosis, the patient's condition worsened and he died only 15 days later. This case report illustrates how alpha-fetoprotein-producing gastric adenocarcinomas have a high incidence of venous and lymphatic invasion and a rapid hepatic spread with a very poor prognosis.

Emulsion polymerization of vinyl acetate: safe optimization of a hazardous complex process.

Fast and exothermic discontinuous emulsion polymerization processes are particularly difficult to optimize from both safety and productivity point of view because of the occurrence of side undesired reactions (e.g. chain transfer to monomer, backbiting, propagation of tertiary radicals, termination by disproportion, etc.) and the hazards of boiling phenomena and stable foam formation under atmospheric pressure. Moreover, the relevant number of loading, heating and cooling steps, required before starting the monomer addition (that is, the desired reaction), makes a strict product quality reproducibility very difficult to obtain. Under these operating conditions, it is necessary to employ a suitable combined theoretical and experimental procedure able to detect the optimum process dosing time at both the laboratory and the industrial scale. In this work, it is shown how to use the topological criterion theory together with proper adiabatic calorimeter and RC1 experimental data to safely optimize the synthesis of polyvinyl acetate through the radical emulsion polymerization of vinyl acetate by the means of an indirectly cooled isoperibolic semibatch reactor.

Angioplasty and stenting of the cervical carotid bifurcation under filter protection: a prospective study in a series of 53 patients.

The aim of this study is to assess safety, reliability, ease of use and usefulness of filter protection devices during angioplasty and stenting of stenotic lesions of the cervical carotid bifurcation. Over a period of 42 months, 53 patients harboring a cervical carotid bifurcation stenotic lesion were treated, by angioplasty and/or stenting using filter protection devices of different kinds. The stenosis was atherosclerotic in 48 cases, post-surgical in four and post-radiation in one case. In all cases, the treatment was successful, with good restoration of the luminal diameter. There were three major strokes (5.6%) and one minor stroke (1.9%). Two of these (one major, one minor) occurred a few hours after the stenting procedure and both seemed by all evidence due to a hemorrhagic hyperperfusion syndrome. One hemiparesis and dysphasia occurred two days after the procedure, secondary to subacute thrombosis with occlusion of the stent. One patient complained of three episodes of decrease in visual acuity of the eye ipsilateral to the stenting in the two weeks following treatment. In conclusion, in our experience, use of the devices adds only few minutes to the procedure time; direct lesions of the arterial wall, such as dissections or intraluminal thrombi, related to the use of filters were never observed, and spasm of the distal I.C.A. also proved rapidly regressive. The content of all filters, if any, was histologically examined, but plaque material was found only in one case, probably owing to our primary stenting technique without use of pre-dilation. The major technical drawback is in-filter coagulation, which occurred in 16 cases, occluding the membrane of the filter and thus slowing or blocking intracranial flow. Such an event can be counteracted by a more aggressive anti-coagulation protocol, which could, however, be responsible for the two complications with hemorrhagic brain infarction. Furthermore, we observed two other major neurological events, which bring the incidence of neurological complications in this series as high as 7.5%. Therefore, it is our opinion that safety of filters is not yet proven, and consequently great care must be taken in their use.

Hazard assessment of substances produced from the accidental heating of chemical compounds.

Accidental events concerning process industries can affect not only the staff working in, but also the environment and people living next to the factory. For this reason a regulation is imposed by the European Community to prevent accidents that could represent a risk for the population and the environment. In particular, Directive 96/82/CE, the so-called 'Seveso II directive', requests a risk analysis involving also the hazardous materials generated in accidental events. Therefore, it is necessary to develop simple and economic procedure to foresee the hazardous materials that can be produced in the case of major accidents, among which the accidental heating of a chemical due to a fire or a runaway reaction is one of the most frequent. The procedure proposed in this work is based on evolved gas analysis methodology that consists in coupling two instruments: a thermogravimetric analyzer or a flash pyrolyzer, that are employed to simulate accident conditions, and a FTIR spectrometer that can be used to detect the evolved gas composition. More than 40 materials have been examined in various accident scenarios and the obtained data have been statistically analyzed in order to identify meaningful correlations between the presence of a chemical group in the molecule of a chemical and the presence of a given hazardous species in the fume produced.

Brain protection with intracarotid filter in angioplasty and stenting of the cervical carotid bifurcation. Preliminary experience in five cases.

SUMMARY: We report our preliminary experience in five cases of carotid stenting and angioplasty performed under cerebral protection with new filter devices allowing carotid flow maintenance during the procedure. In four out of five cases solid material was found inside the filters after balloon inflation for angioplasty. The technical aspects are discussed with correlation to carotid plaque embolic behavior and to functional factors.

A case of concomitant impairment of operational signs and punctuation marks.

A patient affected by amnestic aphasia, E.B., presented with a prevailing impairment in the use of operational signs and punctuation marks. His performance on tasks exploring his knowledge of these symbols is compared with that of two other patients suffering from similar aphasic disturbances. This comparison enables us to reject the hypothesis that E.B.'s defects arise from aphasia per se. A possible cognitive link between operational signs and punctuation marks is discussed.

Neuropsychological evaluation of bleeding cirrhotic patients.

The cognitive profile was evaluated after an acute episode of esophageal bleeding in 26 patients with non-alcoholic hepatic cirrhosis and no previous history of acute hepatic encephalopathy. The neuropsychological test battery employed had been calibrated and standardized for age, sex, and education on a sample of 321 normal subjects. Cognitive deficits were found in some of the patients but it was not possible to selectively identify the tests that they failed or to establish a scale of severity for their scores. Further, there was no significant correlation between the psychometric and metabolic parameters. It would seem that the influence of chronic liver disease on brain functions builds up to a threshold effect, a hypothesis that calls for longitudinal studies.