136 research outputs found

    The emergence of commercial genomics: analysis of the rise of a biotechnology subsector during the Human Genome Project, 1990 to 2004.

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    BackgroundDevelopment of the commercial genomics sector within the biotechnology industry relied heavily on the scientific commons, public funding, and technology transfer between academic and industrial research. This study tracks financial and intellectual property data on genomics firms from 1990 through 2004, thus following these firms as they emerged in the era of the Human Genome Project and through the 2000 to 2001 market bubble.MethodsA database was created based on an early survey of genomics firms, which was expanded using three web-based biotechnology services, scientific journals, and biotechnology trade and technical publications. Financial data for publicly traded firms was collected through the use of four databases specializing in firm financials. Patent searches were conducted using firm names in the US Patent and Trademark Office website search engine and the DNA Patent Database.ResultsA biotechnology subsector of genomics firms emerged in parallel to the publicly funded Human Genome Project. Trends among top firms show that hiring, capital improvement, and research and development expenditures continued to grow after a 2000 to 2001 bubble. The majority of firms are small businesses with great diversity in type of research and development, products, and services provided. Over half the public firms holding patents have the majority of their intellectual property portfolio in DNA-based patents.ConclusionsThese data allow estimates of investment, research and development expenditures, and jobs that paralleled the rise of genomics as a sector within biotechnology between 1990 and 2004

    Device calibration impacts security of quantum key distribution

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    Characterizing the physical channel and calibrating the cryptosystem hardware are prerequisites for establishing a quantum channel for quantum key distribution (QKD). Moreover, an inappropriately implemented calibration routine can open a fatal security loophole. We propose and experimentally demonstrate a method to induce a large temporal detector efficiency mismatch in a commercial QKD system by deceiving a channel length calibration routine. We then devise an optimal and realistic strategy using faked states to break the security of the cryptosystem. A fix for this loophole is also suggested.Comment: 4 pages + 1 page of supplementary information. Considerable modification of Eve's attack strategy and QBER minimization technique. All figures have also been improve

    The resident-as-teacher educational challenge: a needs assessment survey at the National Autonomous University of Mexico Faculty of Medicine

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    <p>Abstract</p> <p>Background</p> <p>The role of residents as educators is increasingly recognized, since it impacts residents, interns, medical students and other healthcare professionals. A widespread implementation of resident-as-teacher courses in developed countries' medical schools has occurred, with variable results. There is a dearth of information about this theme in developing countries. The National Autonomous University of Mexico (UNAM) Faculty of Medicine has more than 50% of the residency programs' physician population in Mexico. This report describes a needs assessment survey for a resident as teacher program at our institution.</p> <p>Methods</p> <p>A cross-sectional descriptive survey was developed based on a review of the available literature and discussion by an expert multidisciplinary committee. The goal was to identify the residents' attitudes, academic needs and preferred educational strategies regarding resident-as-teacher activities throughout the residency. The survey was piloted and modified accordingly. The paper anonymous survey was sent to 7,685 residents, the total population of medical residents in UNAM programs in the country.</p> <p>Results</p> <p>There was a 65.7% return rate (5,186 questionnaires), a broad and representative sample of the student population. The residents felt they had knowledge and were competent in medical education, but the majority felt a need to improve their knowledge and skills in this discipline. Most residents (92.5%) felt that their role as educators of medical students, interns and other residents was important/very important. They estimated that 45.5% of their learning came from other residents. Ninety percent stated that it was necessary to be trained in teaching skills. The themes identified to include in the educational intervention were mostly clinically oriented. The educational strategies in order of preference were interactive lectures with a professor, small groups with a moderator, material available in a website for self-learning, printed material for self-study and homework, and small group web-based learning.</p> <p>Conclusions</p> <p>There is a large unmet need to implement educational interventions to improve residents' educational skills in postgraduate educational programs in developing countries. Most perceived needs of residents are practical and clinically oriented, and they prefer traditional educational strategies. Resident as teachers educational interventions need to be designed taking into account local needs and resources.</p

    Full-field implementation of a perfect eavesdropper on a quantum cryptography system

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    Quantum key distribution (QKD) allows two remote parties to grow a shared secret key. Its security is founded on the principles of quantum mechanics, but in reality it significantly relies on the physical implementation. Technological imperfections of QKD systems have been previously explored, but no attack on an established QKD connection has been realized so far. Here we show the first full-field implementation of a complete attack on a running QKD connection. An installed eavesdropper obtains the entire 'secret' key, while none of the parameters monitored by the legitimate parties indicate a security breach. This confirms that non-idealities in physical implementations of QKD can be fully practically exploitable, and must be given increased scrutiny if quantum cryptography is to become highly secure.Comment: Revised after editorial and peer-review feedback. This version is published in Nat. Commun. 8 pages, 6 figures, 1 tabl

    Quantum Eavesdropping without Interception: An Attack Exploiting the Dead Time of Single Photon Detectors

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    The security of quantum key distribution (QKD) can easily be obscured if the eavesdropper can utilize technical imperfections of the actual implementation. Here we describe and experimentally demonstrate a very simple but highly effective attack which even does not need to intercept the quantum channel at all. Only by exploiting the dead time effect of single photon detectors the eavesdropper is able to gain (asymptotically) full information about the generated keys without being detected by state-of-the-art QKD protocols. In our experiment, the eavesdropper inferred up to 98.8% of the key correctly, without increasing the bit error rate between Alice and Bob significantly. Yet, we find an evenly simple and effective countermeasure to inhibit this and similar attacks

    Hacking commercial quantum cryptography systems by tailored bright illumination

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    The peculiar properties of quantum mechanics allow two remote parties to communicate a private, secret key, which is protected from eavesdropping by the laws of physics. So-called quantum key distribution (QKD) implementations always rely on detectors to measure the relevant quantum property of single photons. Here we demonstrate experimentally that the detectors in two commercially available QKD systems can be fully remote-controlled using specially tailored bright illumination. This makes it possible to tracelessly acquire the full secret key; we propose an eavesdropping apparatus built of off-the-shelf components. The loophole is likely to be present in most QKD systems using avalanche photodiodes to detect single photons. We believe that our findings are crucial for strengthening the security of practical QKD, by identifying and patching technological deficiencies.Comment: Revised version, rewritten for clarity. 5 pages, 5 figures. To download the Supplementary information (which is in open access), go to the journal web site at http://dx.doi.org/10.1038/nphoton.2010.21

    Feasibility of free space quantum key distribution with coherent polarization states

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    We demonstrate for the first time the feasibility of free space quantum key distribution with continuous variables under real atmospheric conditions. More specifically, we transmit coherent polarization states over a 100m free space channel on the roof of our institute's building. In our scheme, signal and local oscillator are combined in a single spatial mode which auto-compensates atmospheric fluctuations and results in an excellent interference. Furthermore, the local oscillator acts as spatial and spectral filter thus allowing unrestrained daylight operation.Comment: 12 pages, 8 figures, extensions in sections 2, 3.1, 3.2 and 4. This is an author-created, un-copyedited version of an article accepted for publication in New Journal of Physics (Special Issue on Quantum Cryptography: Theory and Practice). IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from i

    Topical application of ALA and ALA hexyl ester on a subcutaneous murine mammary adenocarcinoma: tissue distribution

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    Although 5-aminolevulinic acid (ALA)-based photodynamic therapy (PDT) has proven to be clinically beneficial for the treatment of certain cancers, including a variety of skin cancers, optimal tissue localisation still remains a problem. An approach to improve the bioavailability of protoporphyrin IX (PpIX) is the use of ALA derivatives instead of ALA. In this work, we employed a subcutaneous murine mammary adenocarcinoma to study the tissue distribution pattern of the ALA hexyl ester (He-ALA) in comparison with ALA after their topical application in different vehicles. He-ALA induced porphyrin synthesis in the skin overlying the tumour (SOT), but it did not reach the tumour tissue as efficiently. Only 5 h after He-ALA lotion application, tumour porphyrin levels surpassed control values. He-ALA delivered in cream induced a substantially lower porphyrin synthesis in SOT, reinforcing the importance of the vehicle in the use of topical PDT. Porphyrin levels in internal organs remained almost within control values when He-ALA was employed. The addition of DMSO to ALA formulation slightly increased tumour and SOT porphyrin biosynthesis, but it did not when added to He-ALA lotion
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