Electron spectroscopy for chemical analyses (ESCA)—A tool for studying treated textiles

Electron spectroscopy for chemical analysis (ESCA) has been successfully used to determine the location of flame-retardant polymers or reagents and crosslinking and oil/water-repellent reagents in relation to fiber surfaces of chemically modified cotton fabrics and cotton/polyester blends. Changes in intensity of characteristic ESCA element signals were followed as the particle size of the treated fabric varied. Dimethyloldihydroxyethyleneurea (DMDHEU) and the flame-retardant polymer formed from tetrakis(hydroxymethyl)phosphonium chloride (Thpc) and urea penetrate and are homogeneously deposited throughout cotton fabrics. The oil/water-repellent finish, FC-218, and the flame retardants from the THPOH/NH₃ reaction and tris(dibromopropyl) phosphate are deposited on the surfaces of both cotton and polyester fibers.     

New Variant Risks — Are They Real or Perceived?

My friends Teresa and John are competent and experienced computer users. Luckily they are also fastidious and have a social conscience, and you will realize how important these attributes are in a climate of uncertainty regarding the increasing and more frequent proliferation of newer and more damaging worm and virus variants. I received a text message on my mobile phone on Sunday saying, “If you received email from us, please delete. We found a virus.” They were caught badly, opening email from a reputable source a little too hastily. They quickly realized the implications though, and pulled the plug abruptly.     

Utility of an integrated clinical, echocardiographic, and venous ultrasonographic approach for triage of patients with suspected pulmonary embolism

The potential role of ultrasound techniques in diagnosing acute pulmonary embolism (PE) has been investigated in severe cases with hemodynamic compromise, but is still unclear for the whole clinical spectrum of patients with suspected PE. The aim of this study was to assess the utility of an integrated bedside evaluation for PE based on the combination of a clinical score, 2-dimensional echocardiography, and color venous duplex scanning. A group of 117 consecutive patients with suspected PE was assessed using a clinical likelihood score, echocardiography, and venous duplex scanning in order to obtain a preliminary diagnosis of PE, which was subsequently compared with the final diagnosis obtained by lung perfusion scintigraphy and angiography. A preliminary diagnosis of PE was made in 70 patients; a final diagnosis of PE was made in 63 patients, of which 56 had and 7 did not have a preliminary diagnosis of PE. The preliminary diagnosis therefore showed 89% sensitivity and 74% specificity, with a total accuracy of 82%. In patients with massive PE, sensitivity and negative predictive values of the preliminary diagnosis were 97% and 98%, respectively. Echocardiography was poorly sensitive (51%) but highly specific (87%) for PE. Thus, the integration of clinical likelihood, echocardiography, and venous duplex scanning provides a practical approach to patients with suspected PE, allows the rapid implementation of appropriate management strategies, and may reduce or postpone the need for further instrumental evaluation of more limited access.     

A Storm you Really Need to Weather

Packet Storm (www.packetstorm.securify.com) is a security site with an interesting mission statement: “To ensure that Packet Storm is a security resource that provides the mechanism for both the underground and the corporate communities to converge and direct their efforts towards sharing security information.” Describing themselves as the largest and most up-to-date security database in the world, about half their content is submitted from interested parties. Accepting the fact that information must be shared in order to crack the myriad of security threats, Packet Storm follows a strict policy of full-disclosure, publishing all pertinent information that they receive on security-related materials. In fact, they openly invite all of us to submit relevant information or well-written articles for inclusion in their archives and new files section.     

On the Utility of Chirp Modulation for Digital Signaling

The issue of signal selection in binary data transmission is presented. The question of the relative utility of linear frequency sweeping (LFS or chirp), compared to PSK and FSK, in terms of error probability and spectrum usage, is discussed. The transmission media considered are the coherent, partially coherent, Rayleigh, and Rician channel models. Theoretically, LFS has unconditionally superior characteristics in the partially coherent and fading cases, for certain ranges of channel conditions. This is due to the more negative values of cross-coherence parameters possible with the LFS signal set over the FSK signal set. For the fading channel, theoretical supremacy of LFS over FSK depends upon the specular-to-Rayleigh signal power ratio and the adjustability of in-phase cross coherence, with a constraint upon quadrature phase cross coherence. From a practical standpoint, coherent reception of the LFS signal set has severe limitations. These are manifested primarily in two aspects: the need for phase synchronization of a chirp signal set, and the fact that the optimum value of cross coherence is highly sensitive to synchronization channel signal-to-noise ratio (SNR), and/or spectral-to-Rayleigh signal power ratio. The latter would require that modulation characteristics track the channel conditions in order to achieve the supremacy in performance theoretically predicted by optimization of the cross-coherence parameter in LFS.     

Get Yourself a Free Education

I think I may have finally found a one-stop computer security website. If there are any more out there, I am sure I will find them, but for now, I like this one, and will use it regularly. TECS, (www.itsecurity.com) standing for The Encyclopaedia of Computer Security describes itself as ‘all things security to all security people.’ This is the kind of website that managers, administrators, educators and journalists need.     

‘There be Dragons!’

What about this for a dramatic opener? “Greetings! Without your knowledge or explicit permission, the Windows networking technology which connects your computer to the Internet may be offering some or all of your computer’s data to the entire world at this very moment!” The website from which this is taken is called Shields Up (https://grc.com) and is dedicated to researching Internet security for Windows users. There are tools here for the taking that will give you an instant picture of your current level of security — or lack of it, as the case may be.     

Laboratory tests for assessing efficacy of atoxigenic Aspergillus flavus strains as biocontrol agents

Biocontrol by competitive inhibition using atoxigenic Aspergillus flavus strains has been shown to be an effective method for controlling aflatoxin production in peanuts, maize and cottonseed. Selecting biocontrol strains is not straightforward, as it is difficult to assess fitness for the task without expensive field trials. Reconstruction experiments have been generally performed under laboratory conditions to investigate the biological mechanisms underlying the efficacy of atoxigenic strains in preventing aflatoxin production and/or to give a preliminary indication of strain performance when released in the field. The study here described was conducted in order to evaluate the potential of the different atoxigenic A. flavus strains, colonizing the corn fields of the Po Valley, in reducing aflatoxin accumulation when grown in mixed cultures together with atoxigenic strains; additionally, we developed a simple and inexpensive procedure that may be used to scale-up the screening process and to increase knowledge on the mechanisms interfering with mycotoxin production during co-infection.