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Detection of bacterial endospores by means of ultrafast coherent raman spectroscopyPestov, Dmitry Sergeyevich 10 October 2008 (has links)
This work is devoted to formulation and development of a laser spectroscopic technique
for rapid detection of biohazards, such as Bacillus anthracis spores. Coherent anti-Stokes
Raman scattering (CARS) is used as an underlying process for active retrieval of
species-specific characteristics of an analyte. Vibrational modes of constituent molecules
are Raman-excited by a pair of ultrashort, femtosecond laser pulses, and then probed
through inelastic scattering of a third, time-delayed laser field.
We first employ the already known time-resolved CARS technique. We apply it
to the spectroscopy of easy-to-handle methanol-water mixtures, and then continue
building our expertise on solutions of dipicolinic acid (DPA) and its salts, which happen
to be marker molecules for bacterial spores. Various acquisition schemes are evaluated,
and the preference is given to multi-channel frequency-resolved detection, when the
whole CARS spectrum is recorded as a function of the probe pulse delay. We
demonstrate a simple detection algorithm that manages to differentiate DPA solution
from common interferents. We investigate experimentally the advantages and
disadvantages of near-resonant probing of the excited molecular coherence, and finally
observe the indicative backscattered CARS signal from DPA and NaDPA powders. The possibility of selective Raman excitation via pulse shaping of the preparation pulses is
also demonstrated.
The analysis of time-resolved CARS experiments on powders and B. subtilis
spores, a harmless surrogate for B. anthracis, facilitates the formulation of a new
approach, where we take full advantage of the multi-channel frequency-resolved
acquisition and spectrally discriminate the Raman-resonant CARS signal from the
background due to other instantaneous four-wave mixing (FWM) processes. Using
narrowband probing, we decrease the magnitude of the nonresonant FWM, which is
further suppressed by the timing of the laser pulses. The devised technique, referred to as
hybrid CARS, leads to a single-shot detection of as few as 104 bacterial spores, bringing
CARS spectroscopy to the forefront of potential candidates for real-time biohazard
detection. It also gives promise to many other applications of CARS, hindered so far by
the presence of the overwhelming nonresonant FWM background, mentioned above.
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The Biohazard Message: Epidemics, Biological Accidents and Bioterrorism in Fiction (1969-1999)Bacardit i Raluy, Albert 15 March 2010 (has links)
No description available.
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Isolement de fragments d'anticorps recombinants neutralisant des toxines à partir de primates non humains et localisation de l'épitope d'un anticorps. / Isolation of non-human primates recombinant antibody fragments neutralizing toxins and antibody epitope mappingAvril, Arnaud 16 September 2013 (has links)
Les anticorps recombinants représentent une approche prometteuse pour améliorer le traitement et la prophylaxie des maladies causées par les armes biologiques. De tels anticorps peuvent être isolés à partir de primates non humains, dont l'immunisation est plus facile à concevoir et à réaliser que l'immunisation d'humains. Des chimpanzés (Pan troglodytes) et des macaques (Macaca mulatta et M. fascicularis) ont été utilisés pour de tels travaux, et notre analyse de séquences a démontré que l'utilisation de chimpanzés n'apporte pas d'avantage significatif malgré leur plus grande proximité phylogénétique avec l'Homme. La suite de ce travail a donc utilisé des macaques, plus facilement accessibles en France que les chimpanzés. Dans le cadre du projet européen AntiBotABE, des banques immunes exposées àla surface de phages ont été construites à partir de macaques (M. fascicularis) immunisés puis criblées, et des scFv neutralisant simultanément les toxines botuliques (BoNT) A1 et A2 en ciblant leurs chaines lourdes, et BoNT/E3 en ciblant sa chaine légère ont été isolés. D'autre part, un anticorps neutralisant de façon croisée la toxine létale et la toxine oedémateuse de Bacillus anthracis avait été précédemment isolé. Ses épitopes ont été localisés au cours de la présente thèse par une méthode tirant partie de cette réactivité croisée. Ils correspondent à la région [229-230]-[234-236] de la sous-unité LF (Lethal Factor) et à la région [229-230]-[234-236] de la sous-unité EF (Edema Factor). Le principe de cette localisation d'épitope pourrait être ré-employé pour localiser les épitopes des scFv neutralisant les BoNT. / Recombinant antibodies represent a promising approach to improve the treatment andprophylaxis of diseases caused by bioweapons. Such antibodies may be isolated from nonhumanprimates, whose immunization is much easier to conceive and realized thanimmunization of humans. Chimpanzees (Pan troglodytes) and macaques (Macaca mulattaand M. fascicularis, particularly) have been utilized for such purposes, and our sequenceanalysis has demonstrated that using chimpanzees does not bring a significant advantagedespite their closer phylogenetic proximity with humans. The rest of this thesis has thusutilized macaques, easier to access in France than chimpanzees. In the context of theEuropean AntiBotABE project, phage-displayed immune libraries have been constructed fromimmunized macaques (M. fascicularis) then screened, and scFv simultaneously neutralizingbotulinum toxins (BoNT) A1 and A2 by targeting their heavy chains, and BoNT/E3 bytargeting its light chain were isolated. On the other side, an antibody cross-neutralizing thelethal toxin and the edema toxin of Bacillus anthracis had been formerly isolated. Its epitopeshave been mapped in the course of the present thesis by a method taking advantage of itscross-reactivity. They correspond to the [229-230]-[234-236] region of LF (Lethal Factor)subunit and to the [229-230]-[234-236] region of EF (Edema Factor) subunit. The principle ofthis epitope mapping could be re-employed to map the epitopes of BoNT-neutralizing scFv.
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Investigation and development of a framework for medical waste managementAlhadlaq, Abdullah Abdulaziz January 2014 (has links)
The Kingdom of Saudi Arabia is the largest country in the golf states and one of the richest oil producing countries. Saudi population is nearly 27million; in addition, Saudi Arabia receives millions of people from around the world for Islamic pilgrimages. Moreover, Saudi is hosting hundreds of thousands of international professionals and labourers. Hence, the country infrastructure and services have been in the top agenda to be modernized in order to cope with new demand for better quality of life for a rich country. The healthcare sector is one of the key sectors which requires a special on going attention, particularly medically generated waste. Therefore, this research work has been conducted to investigate the status of medical waste management in the capital city; Riyadh. The prime aim of this research work is to propose a strategic framework which can be used as a roadmap for the different stakeholders. This will contribute to the enforcement of better handling and treatment of medical waste and more importantly prevent and control the spread of diseases or harm might be caused by poor handling of medical waste. The aim of the research has been achieved through; the critical review and analysis of the relevant literature, which has revealed the noticeable gap and lack of scientific studies of the proposed field. Appropriately, the findings of the research has contributed to filling the gap of the knowledge as well as serving as a milestone for further research work in this very important field. By surveying Riyadh’s hospitals and other national and international reports has. This allowed the presentation of the facts and indications of the current status of medical waste in Riyadh City. To obtain in-depth knowledge and gather the important findings concerning the medical waste management, focused; interviews of different medical professionals from various hospitals were conducted. This research has revealed more important factors that need to be addressed. These findings were used to propose the framework, which has been formed to enable resolving the challenges of the integration, of the awareness element though Islamic principles, within the Saudi system. The proposed framework has been evaluated by committee of medical professionals and has been accepted as good roadmap and appropriate solution that address the main aim of this research work. Finally, the research work is just a step towards the establishment of a proper biomedical waste management system in the Kingdom of Saudi Arabia. Some recommendations for future implementation are suggested at the end of this thesis.
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Komplexní přístup poskytovatele zdravotnické záchranné služby k transportu pacienta s vysoce nakažlivou nemocí / A comprehensive approach of emergency medical services providers to a transport of a patient suffering from a highly contagious diseaseMACH, Rostislav January 2019 (has links)
In the thesis "Comprehensive approach of emergency medical services provider to a highly-contagious patient transportation" we concentrated on nursing care and aspects of transportation administered by operating paramedics, all in cases that public health authorities suspect to be related to a highly - contagious disease and transportation in isolated transportation vehicle is mandated. The theoretical part of the thesis defines the key concepts of highly - contagious disease, it describes individual causal agents of contagious diseases and their ways of transmission to humans. For description of contagious diseases were chosen those with high morbidity, lethality and interpersonal transmission. We mention the danger of biological agents misuse, ways of protection against contagious diseases and types of decontamination procedures. We describe different means of personal protection used by biohazard team members and even environmental factors affecting the work of paramedics using personal protective agents. Further on, we bring to attention legal aspects and inner policies related to aforementioned issues including analysis of procedure logistics of emergency services teams dealing with emergencies with suspicion of highly - contagious disease. Research in practical part of the thesis concentrates on aims related to optimizing nursing care for patients suspected of suffering from a highly - contagious disease, when securing them in the transportation vehicle, furthermore, we examine the impact of personal protective agents used by paramedics when transporting the patient, and we also analyze environmental factors inside the ambulance vehicle and isolated personal transportation vehicle. All of these aims were researched with the help of planned experiments and the resulting findings are based on the outcomes of these experiments.
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Biological Agent Sensing Integrated Circuit (BASIC): A New Complementary Metal-oxide-semiconductor (CMOS) Magnetic Biosensor SystemZheng, Yi 10 June 2014 (has links)
Fast and accurate diagnosis is always in demand by modern medical professionals and in the area of national defense. At present, limitations of testing speed, sample conditions, and levels of precision exist under current technologies, which are usually slow and involve testing the specimen under laboratory conditions. Typically, these methods also involve several biochemical processing steps and subsequent detection of low energy luminescence or electrical changes, all of which reduce the speed of the test as well as limit the precision. In order to solve these problems and improve the sensing performance, this project proposes an innovative CMOS magnetic biological sensor system for rapidly testing the presence of potential pathogens and bioterrorism agents (zoonotic microorganisms) both in specimens and especially in the environment. The sensor uses an electromagnetic detection mechanism to measure changes in the number of microorganisms--tagged by iron nanoparticles--that are placed on the surface of an integrated circuit (IC) chip. Measured magnetic effects are transformed into electronic signals that count the number and type of organisms present. This biosensor introduces a novel design of a conical-shaped inductor, which achieves ultra-accuracy of sensing biological pathogens. The whole system is integrated on a single chip based on the fabrication process of IBM 180 nm (CMOS_IBM_7RF), which makes the sensor small-sized, portable, high speed, and low cost. The results of designing, simulating, and fabricating the sensor are reported in this dissertation. / Ph. D.
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