Direct observation of a propagating spin wave induced by spin-transfer torque.

Spin torque oscillators with nanoscale electrical contacts are able to produce coherent spin waves in extended magnetic films, and offer an attractive combination of electrical and magnetic field control, broadband operation, fast spin-wave frequency modulation, and the possibility of synchronizing multiple spin-wave injection sites. However, many potential applications rely on propagating (as opposed to localized) spin waves, and direct evidence for propagation has been lacking. Here, we directly observe a propagating spin wave launched from a spin torque oscillator with a nanoscale electrical contact into an extended Permalloy (nickel iron) film through the spin transfer torque effect. The data, obtained by wave-vector-resolved micro-focused Brillouin light scattering, show that spin waves with tunable frequencies can propagate for several micrometres. Micromagnetic simulations provide the theoretical support to quantitatively reproduce the results.

Mandibular osteomyelitis due to Pseudomonas aeruginosa. Case report.

Osteomyelitis is a relatively frequent bacterial infection of the jaw bones. This report describes a case of mandibular osteomyelitis in a surgical site after enucleation of a follicular cyst and extraction of the associated tooth. This case is unusual because maxillary osteomyelitis generally results from polymicrobial infection. In our patient, however, laboratory analysis identified Pseudomonas aeruginosa as the etiologic agent, an opportunistic pathogen normally found on moist surfaces and vegetation. Notorious for its antibiotic multiresistance, P. aeruginosa is increasingly recognized as a serious problem in hospitalized patients. Isolation of the responsible microbe permitted specific antibiotic treatment with a 10-day course of ciprofloxacin (250 mg/12 h), which fully cleared the infection.

[Cardiovascular adjustments in hypertensive patients. An echocardiographic study]. / Adattamenti cardiovascolari in ipertesi. Studio ecocardiografico.

Echocardiography was used to asses parameters of cardiovascular function in order to identify the main cardiac adjustment mechanisms to arterial hypertension. In addition to morphological parameters of septal and parietal thickness and diameter, telesystolic (Ses) and telediastolic (Spk) stress, EF, Vcfm, the index of left ventricular mass (ILVM), hypertrophy ratio (h/r), contractility index (Do), peripheral resistances (RPT) and Tarazi's index (SAC) were evaluated. In comparison to control subjects, higher levels of PwTs, h/r, SAC, RPT and ILVM (at the limit of significance) were found in hypertensive patients, which were reflected by higher Spk and Do values. From the further analysis of data to identify patients with signs of left ventricular hypertrophy (h/r greater than 0.40 and/or ILVM greater than 140) it was concluded that the hypertrophy ratio (h/r) is the functional parameter which most closely reveals the type of myocardial adjustment. Irrespective of absolute values of ILVM, the adequacy of myocardial hypertrophy to the dimensions of the cavity is accompanied by the normalisation of stress and the return of Do values close to normal levels. Hearts with low h/r those with the highest stress levels, as well as preesting the lowest EF and the highest Do values.

[Sinus arrhythmia: quantitative evaluation and possible use in the diagnosis of sick sinus syndrome (author's transl)]. / L'aritmia sinusale: Valutazione quantitativa e prospettive di impiego nella diagnostica della malattia del nodo del seno.

This research was done in order to quantify the sinus arrhythmia and to determine any possible quantitative difference between normal subjects and patients with Sick Sinus Syndrome (SSS). The ECG of 200 normal subjects and 30 patients with SSS diagnosed with electrophysiologic evaluation have been studied. 50 consecutive PP intervals have been measured in each ECG, and the average and standard deviation (SD) were calculated. The variableness of the sinus cycle was expressed by the Sinus Arrhythmia Index (SAI), obtained by the ratio between the SD and the average length of the cycle. It was observed that in normal subjects the SAI decreases with aging, and its value is not related to the heart rate. The SAI was significantly higher in the patients with SSS than in the normal ones. Since a sinus arrhythmia of high degree may be observed in the SSS, the quantitative evaluation of this arrhythmia, obtained by the index we proposed, may be useful to the detection of this syndrome.