Detection of ultra-low protein concentrations with the simplest possible field effect transistor

Silicon nanowire (Si NW) sensors have attracted great attention due to their ability to provide fast, low-cost, label-free, real-time detection of chemical and biological species. Usually configured as field effect transistors (FETs), they have already demonstrated remarkable sensitivity with high selectivity (through appropriate functionalisation) towards a large number of analytes in both liquid and gas phases. Despite these excellent results, Si NW FET sensors have not yet been successfully employed to detect single molecules of either a chemical or biological target species. Here we show that sensors based on silicon junctionless nanowire transistors (JNTs), the simplest possible transistors, are capable of detecting the protein streptavidin at a concentration as low as 580 zM closely approaching the single molecule level. This ultrahigh detection sensitivity is due to the intrinsic advantages of junctionless devices over conventional FETs. Apart from their superior functionality, JNTs are much easier to fabricate by standard microelectronic processes than transistors containing p–n junctions. The ability of JNT sensors to detect ultra-low concentrations (in the zeptomolar range) of target species, and their potential for low-cost mass production, will permit their deployment in numerous environments, including life sciences, biotechnology, medicine, pharmacology, product safety, environmental monitoring and security

Management education and the theatre of the absurd

In this paper we adopt a humanities perspective to reflect on the nature of business schools and management education (Vargish, 1991; March & Weil, 2005; Adler, 2006; McAuley & Sims, 2009). Business schools have been criticised for becoming the “hired hands” of business (Khurana, 2007) to the detriment of a higher purpose, institutions that champion a utilitarian morality, the shallowness and indeed the dangers of which are revealed in various business scandals and especially the financial crisis of 2007-8, the effects of which cast a long shadow over today’s economic and social landscape. This has led to the criticism that business schools have lost part of their essential “philosophic connection” to issues of humanity and human identities (Augier & March, 2011: 233-4). We argue that one way to encourage philosophical reconnection is to expand management education’s engagement with the humanities (Czarniawska & Gagliardi, 2006)

L'infection genitale par les herpes simplex virus parmi des hommes consultant pour un depistage des papillomavirus genitaux

OBJECTIVE. Our aim was to assess the frequency of herpetic genital infection (HSV) among men attending a human papillomavirus (HPV) screening centre. Clinical screening of a herpetic lesion was completed with biological detection of HSV by cell culture and by polymerase chain reaction (PCR). We also evaluated the role of the male viral factor on the female partners. METHOD. We performed a genital examination by colposcopy of 135 men whose female partners presented an HPV genital infection. The HPV lesions detected underwent biopsy by Southern blot viral analysis. The lesions which clinically appeared to be caused by HSV were removed for HSV detection and typing by cell culture and by PCR. Sperm was collected for viral detection by cell culture and PCR was collected for viral detection by cell culture and PCR from patients presenting a herpetic type urethral symptomatology. RESULTS. Peniscopy detected HPV lesions in 46 p. 100 of the men, in 88 p. 100 of cases in the balano-preputial zone and in 82 p. 100 of cases their morphology was exophytic. The other areas were in 14.5 p. 100 of cases urethral and 9 p. 100 anal. We detected a dysplasic lesion in 6 p. 100 of cases. In 74 p. 100 of cases molecular hybridization by Southern detected 6/11/42 type HPV and in 6.4 p. 100 of cases HPV 16. Clinical examination revealed the presence of genital herpetic infection in 15.5 p. 100 of cases, of these 76 p. 100 were preputial and 24 p. 100 meato-urethral. PCR detected HSV-2 in 88 p. 100 of the preputial lesions and in 86 p. 100 of the spermatic ejaculates from the meato-urethral lesions. The chi 2 test showed that no link exists between a herpetic genital infection and the presence of an HPV lesion, but that the risk is greater (OR = 2.15; IC 95 p. 100 = 0.84-5.49). We also observed that 50 p. 100 of the female partners of men with both HPV+HSV infections had high grade cervical lesions. CONCLUSION. This study shows that clinical examination in an HPV screening centre enabled detection of clinical HSV in 15.5 p. 100 of cases as opposed to 17 p. 100 biologically. Thus the good clinical-virological correlation shows that clinical criteria remain the principal elements for detecting viral genital infections, it therefore appears advantageous to only use the new HSV identification techniques for targeted detection. Also, herpetic genital infection is independent of human papillomavirus infection. When screening for HPV, herpetic genital infection should be taken into account as we have observed that the female partners of men with both HPV + HSV are at greater risk of presenting high grade cervical lesions