Polyphasic approach for differentiating Penicillium nordicum from Penicillium verrucosum

The aim of this research was to use a polyphasic approach to differentiate Penicillium verrucosum from Penicillium nordicum, to compare different techniques, and to select the most suitable for industrial use. In particular, (1) a cultural technique with two substrates selective for these species; (2) a molecular diagnostic test recently set up and a RAPD procedure derived from this assay; (3) an RP-HPLC analysis to quantify ochratoxin A (OTA) production and (4) an automated system based on fungal carbon source utilisation (Biolog Microstation?) were used. Thirty strains isolated from meat products and originally identified as P. verrucosum by morphological methods were re-examined by newer cultural tests and by PCR methods. All were found to belong to P. nordicum. Their biochemical and chemical characterisation supported the results obtained by cultural and molecular techniques and showed the varied ability in P. verrucosum and P. nordicum to metabolise carbon-based sources and to produce OTA at different concentrations, respectively.     

Research review

Berni Dwan examines research in product push attacks, Internet data integrity and a collaborative research consortium in the Northern Hemisphere     

Clinical significance of small left-to-right shunts after percutaneous mitral valvuloplasty

Left-to-right shunt after percutaneous mitral valvuloplasty was evaluated by contrast echocardiography in 29 patients at 24 hours and at 1, 3, 6, and 9 months after the procedure. The patients were divided into two groups: in group A (13 patients) the double-balloon technique was used; in group B (16 patients) the Inoue single-balloon technique was used. The two groups were comparable in terms of age, gender, and mitral valve area before and after percutaneous mitral valvuloplasty. A left-to-right shunt was detected in all patients 24 hours after the procedure. At 1 month follow-up the shunt was present in 12 patients of group A (92%) and in 13 of group B (81%) with a statistically significant difference (p < 0.001). At 3 months the values were 7 (54%) in group A and 6 (37.5%) in group B (p < 0.05); at 6 months the values were 3 (23%) in group A and 3 (19%) in group B (NS). At 9 months a left-to-right shunt was no longer detectable in any of the patients in either group. The disappearance of the shunt could be related to a healing process of the atrial septal injury that occurs within a few months after percutaneous mitral valvuloplasty. This process seems to be more rapid in group B patients, probably because of the smaller lesion that is produced in the atrial septum by the passage of the Inoue balloon.     

Silica content of dusts from five texas cottonseed oil mills

Total dust samples, collected with high-volume samplers, were ashed and then analyzed for aluminum, silicon and silica (SiO₂). Ash and aluminum contents agreed with earlier reported data, but the silicon content was lower. The amounts of silica ranged from 2–7% in dusts from the cleaning rooms to 0.01–0.05% in dusts from the baling rooms. Agreement with silica contents determined by infrared (IR) spectrometry was good. IR spectra indicated silica particle diameters were in the range of 6–8 µm in the cleaning rooms and 10 µm or more in the delintering and baling rooms. Threshold limit values (TLV) calculated on the basis of total silica in the high-volume samples suggest silica values above the limit in 4 of the cleaning rooms, and possibly one at the delintering rooms. Calculation of respirable silica concentrations and TLV for respirable silica was precluded by the sampling method.     

Cellulosates of group ia metals—their preparation and reactivity with β-chloroethyldiethylamine

Mercerized cotton printcloth converted to a cellulosate of lithium, sodium, potassium, rubidium, or cesium by reaction with metal methoxide is a good substrate for the preparation of diethylaminoethyl (DEAE) cotton at low temperatures in nonaqueous media. The pretreatment to form the cellulosate of the alkali metal does not adversely affect mechanical properties of the cotton fabric. There is no advantage to using a cellulosate other than sodium cellulosate in reactions with β-chloroethyldiethylamine to form DEAE cotton. The reaction occurs in organic solvents of low and high dielectric constants. The hydrochloride of the amine rather than the free amine can be used to prepare DEAE cotton, provided the ratio of reactants is within specific limits. Consideration has been given to the mechanism of the reaction.     

Comparative electron temperature measurements of Thomson scattering and electron cyclotron emission diagnostics in TCABR plasmas

We present the first simultaneous measurements of the Thomson scattering and electron cyclotron emission radiometer diagnostics performed at TCABR tokamak with Alfve?n wave heating. The Thomson scattering diagnostic is an upgraded version of the one previously installed at the ISTTOK tokamak, while the electron cyclotron emission radiometer employs a heterodyne sweeping radiometer. For purely Ohmic discharges, the electron temperature measurements from both diagnostics are in good agreement. Additional Alfve?n wave heating does not affect the capability of the Thomson scattering diagnostic to measure the instantaneous electron temperature, whereas measurements from the electron cyclotron emission radiometer become underestimates of the actual temperature values.     

All‐MOS implementation of RC networks for time‐controlled Gaussian spatial filtering

This paper addresses the design and VLSI implementation of MOS‐based RC networks capable of performing time‐controlled Gaussian filtering. In these networks, all the resistors are substituted one by one by a single MOS transistor biased in the ohmic region. The design of this elementary transistor is carefully realized according to the value of the ideal resistor to be emulated. For a prescribed signal range, the MOSFET in triode region delivers an interval of instantaneous resistance values. We demonstrate that, for the elementary 2‐node network, establishing the design equation at a particular point within this interval guarantees minimum error. This equation is then corroborated for networks of arbitrary size by analyzing them from a stochastic point of view. Following the design methodology proposed, the error committed by an MOS‐based grid when compared with its equivalent ideal RC network is, despite the intrinsic nonlinearities of the transistors, below 1% even under mismatch conditions of 10%. In terms of image processing, this error hardly affects the outcome, which is perceptually equivalent to that of the ideal network. These results, extracted from simulation, are verified in a prototype vision chip with QCIF resolution manufactured in the AMS 0.35µm CMOS‐OPTO process. This prototype incorporates a focal‐plane MOS‐based RC network that performs fully programmable Gaussian filtering. Copyright © 2011 John Wiley & Sons, Ltd.     

Ultrathin hydroxyapatite coating on pure magnesium substrate prepared by pulsed electron ablation technique

Magnesium (Mg) as a potential material for biodegradable implants is attractive due to its mechanical similarity to the bone tissue and nontoxic corrosion products. However, the rapid corrosion rate of bare magnesium is associated with hydrogen release, which may complicate the healing process. The corrosion rate may be reduced by suitable alloying, but concurrently the biocompatibility of such alloy might be deteriorated. Another way of reduction of the corrosion rate is coating. Hydroxyapatite (HA)-based coating is considered to improve biocompatibility as well as decrease the corrosion rate by the barrier effect. In this study, ultrathin (150 nm) HA and HA containing Sr coatings are deposited via pulsed electron ablation technique on pure Mg. The microstructure of the coating was assessed by scanning electron microscopy. Electrochemical methods were used to investigate the corrosion properties of prepared coatings. The materials covered by this layer were characterized by superior corrosion behavior, with corrosion rates of coated samples up to five times lower as compared with the uncoated ones. Such coating is the thinnest coating found in the literature sources.     

Efficacy and safety of adenosine in diagnosis and treatment of regular tachycardia in the elderly

BACKGROUND: Adenosine is currently used in the treatment and differential diagnosis of regular tachycardia. However, the efficacy of its employment has not been studied in elderly people. METHODS: We evaluated the safety, and the diagnostic and therapeutic utility of adenosine in elderly people aged over 70 years with regular sustained tachycardia, compared with a group of patients aged under 70 years affected by the same arrhythmia. Adenosine was given to 107 patients in increasing bolus doses up to 18 mg during regular broad and narrow complex tachycardia; 49 patients were aged 70 and over, and 58 patients were aged less than 70 years. In the former group, surface ECG showed 38 narrow complex tachycardias and 11 broad complex ones; in the second group there were 48 narrow complex tachycardias and 10 broad complex ones. RESULTS: Adenosine was effective in 94% of the elderly patients and in 93% of the younger patients. In the group aged over 70 years, adenosine restored sinus rhythm in 37% of patients and revealed the mechanism of arrhythmia in 57%. Adenosine restored sinus rhythm in 50% of patients under 70 years and revealed atrial or sinus tachycardia in 43%. The incidence of symptomatic side effects and peri-conversion ventricular arrhythmias was similar in the two groups. There were ventricular pauses over 3 s long in four (8%) of the older patients (maximum pause 7 s) and in two patients (3%) of the group under 70 years (maximum pause 6 s). No adverse haemodynamic effects were observed. CONCLUSION: These data demonstrate the safety and the value of adenosine in the diagnosis and treatment of regular tachycardia in elderly patients.     

A new classification of varicose veins to compare various surgical strategies

Considering the presupposition that chronic venous insufficiency (CVI) and varicose veins classifications are extremely difficult, and that none of those presently in use are sufficiently complete, the authors propose the classification of the haemodynamic venous disease (HVD) and of the varicose veins from the clinical, anatomotopographical, etiopathogenetical and haemodynamical point-of-view. This type of classification allows us to closely follow the disease's evolution, to distinguish the benign forms from the more aggressive ones, and to evaluate the results of the medical, surgical and schlerotherapical treatments, from the efficiently, functional, instrumental and aesthetically point-of-view.