Audit report on the Black Hawk County Criminal Justice Information System for the year ended June 30, 2011

Audit report on the Black Hawk County Criminal Justice Information System for the year ended June 30, 2011

[George F. Knorr] / Black

Donateur : Pavie, Théodore (1811-1896)

Stimulated-echo acquisition mode (STEAM) MRI for black-blood delayed hyperenhanced myocardial imaging.

PURPOSE: To develop a breathhold method for black-blood viability imaging of the heart that may facilitate identifying the endocardial border. MATERIALS AND METHODS: Three stimulated-echo acquisition mode (STEAM) images were obtained almost simultaneously during the same acquisition using three different demodulation values. Two of the three images were used to construct a black-blood image of the heart. The third image was a T(1)-weighted viability image that enabled detection of hyperintense infarcted myocardium after contrast agent administration. The three STEAM images were combined into one composite black-blood viability image of the heart. The composite STEAM images were compared to conventional inversion-recovery (IR) delayed hyperenhanced (DHE) images in nine human subjects studied on a 3T MRI scanner. RESULTS: STEAM images showed black-blood characteristics and a significant improvement in the blood-infarct signal-difference to noise ratio (SDNR) when compared to the IR-DHE images (34 +/- 4.1 vs. 10 +/- 2.9, mean +/- standard deviation (SD), P < 0.002). There was sufficient myocardium-infarct SDNR in the STEAM images to accurately delineate infarcted regions. The extracted infarcts demonstrated good agreement with the IR-DHE images. CONCLUSION: The STEAM black-blood property allows for better delineation of the blood-infarct border, which would enhance the fast and accurate measurement of infarct size.

VEGF is a mediator of retinal pigment epithelium permeability leading to photoreceptor cell death in light-induced retinal degeneration : gene therapy strategy to prevent AMD-disorders

ABSTRACTIn normal tissues, a balance between pro- and anti-angiogenic factors tightly controls angiogenesis. Alterations of this balance may have pathological consequences. For instance, concerning the retina, the vascular endothelial growth factor (VEGF) is a potent pro-angiogenic factor, and has been identified has a key player during ocular neovascularization implicated in a variety of retinal diseases. In the exudative form (wet-form) of age-related macular degeneration (AMD), neovascularizations occurring from the choroidal vessels are responsible for a quick and dramatic loss of visual acuity. In diabetic retinopathy and retinopathy of prematurity, sprouting from the retinal vessels leads to vision loss. Furthermore, the aging of the population, the increased- prevalence of diabetes and the better survival rate of premature infants will lead to an increasing rate of these conditions. In this way, anti-VEGF strategy represents an important therapeutic target to treat ocular neovascular disorders.In addition, the administration of Pigmented Epithelial growth factor, a neurotrophic and an anti- angiogenic factor, prevents photoreceptor cell death in a model of retinal degeneration induced by light. Previous results analyzing end point morphology reveal that the light damage (LD) model is used to mimic retinal degenerations arising from environmental insult, as well as aging and genetic disease such as advanced atrophic AMD. Moreover, light has been identified as a co-factor in a number of retinal diseases, speeding up the degeneration process. This protecting effect of PEDF in the LD retina raises the possibility of involvement of the balance between pro- and anti-angiogenic factors not only for angiogenesis, but also in cell survival and maintenance.The aim of the work presented here was to evaluate the importance of this balance in neurodegenerative processes. To this aim, a model of light-induced retinal degeneration was used and characterized, mainly focusing on factors simultaneously controlling neuron survival and angiogenesis, such as PEDF and VEGF.In most species, prolonged intense light exposure can lead to photoreceptor cell damage that can progress to cell death and vision loss. A protocol previously described to induce retinal degeneration in Balb/c mice was used. Retinas were characterized at different time points after light injury through several methods at the functional and molecular levels. Data obtained confirmed that toxic level of light induce PR cell death. Variations were observed in VEGF pathway players in both the neural retina and the eye-cup containing the retinal pigment epithelium (RPE), suggesting a flux of VEGF from the RPE towards the neuroretina. Concomitantly, the integrity of the outer blood-retinal-barrier (BRB) was altered, leading to extravascular albumin leakage from the choroid throughout the photoreceptor layer.To evaluate the importance of VEGF during light-induced retinal degeneration process, a lentiviral vector encoding the cDNA of a single chain antibody directed against all VEGF-A isoforms was developed (LV-V65). The bioactivity of this vector to block VEGF was validated in a mouse model of laser-induced choroidal neovascularization mediated by VEGF upregulation. The vector was then used in the LD model. The administration of the LV-V65 contributed to the maintenance of functional photoreceptors, which was assessed by ERG recording, visual acuity measurement and histological analyses. At the RPE level, the BRB integrity was preserved as shown by the absence of albumin leakage and the maintenance of RPE cell cohesion.These results taken together indicate that the VEGF is a mediator of light induced PR degeneration process and confirm the crucial role of the balance between pro- and anti-angiogenic factors in the PR cell survival. This work also highlights the prime importance of BRB integrity and functional coupling between RPE and PR cells to maintain the PR survival. VEGF dysregulation was already shown to be involved in wet AMD forms and our study suggests that VEGF dysregulation may also occur at early stages of AMD and could thus be a potential therapeutic target for several RPE related diseases.RESUMEDans les différents tissues de l'organisme, l'angiogenèse est strictement contrôlée par une balance entre les facteurs pro- et anti-angiogéniques. Des modifications survenant dans cette balance peuvent engendrer des conséquences pathologiques. Par exemple, concernant la rétine, le facteur de croissance de l'endothélium vasculaire (VEGF) est un facteur pro-angiogénique important. Ce facteur a été identifié comme un acteur majeur dans les néovascularisations oculaires et les processus pathologiques angiogéniques survenant dans l'oeil et responsables d'une grande variété de maladies rétiniennes. Dans la forme humide de la dégénérescence maculaire liée à l'âge (DMLA), la néovascularisation choroïdienne est responsable de la perte rapide et brutale de l'acuité visuelle chez les patients affectés. Dans la rétinopathie diabétique et celle lié à la prématurité, l'émergence de néovaisseaux rétiniens est la cause de la perte de la vision. Les néovascularisations oculaires représentent la principale cause de cécité dans les pays développés. De plus, l'âge croissant de la population, la progression de la prévalence du diabète et la meilleure survie des enfants prématurés mèneront sans doute à l'augmentation de ces pathologies dans les années futures. Dans ces conditions, les thérapies anti- angiogéniques visant à inhiber le VEGF représentent une importante cible thérapeutique pour le traitement de ces pathologies.Plusieurs facteurs anti-angiogéniques ont été identifiés. Parmi eux, le facteur de l'épithélium pigmentaire (PEDF) est à la fois un facteur neuro-trophique et anti-angiogénique, et l'administration de ce facteur au niveau de la rétine dans un modèle de dégénérescence rétinienne induite par la lumière protège les photorécepteurs de la mort cellulaire. Des études antérieures basées sur l'analyse morphologique ont révélé que les modifications survenant lors de la dégénération induite suite à l'exposition à des doses toxiques de lumière représente un remarquable modèle pour l'étude des dégénérations rétiniennes suite à des lésions environnementales, à l'âge ou encore aux maladies génétiques telle que la forme atrophique avancée de la DMLA. De plus, la lumière a été identifiée comme un co-facteur impliqué dans un grand nombre de maladies rétiniennes, accélérant le processus de dégénération. L'effet protecteur du PEDF dans les rétines lésées suite à l'exposition de des doses toxiques de lumière suscite la possibilité que la balance entre les facteurs pro- et anti-angiogéniques soit impliquée non seulement dans les processus angiogéniques, mais également dans le maintient et la survie des cellules.Le but de ce projet consiste donc à évaluer l'implication de cette balance lors des processus neurodégénératifs. Pour cela, un modèle de dégénération induite par la lumière à été utilisé et caractérisé, avec un intérêt particulier pour les facteurs comme le PEDF et le VEGF contrôlant simultanément la survie des neurones et l'angiogenèse.Dans la plupart des espèces, l'exposition prolongée à une lumière intense peut provoquer des dommages au niveau des cellules photoréceptrices de l'oeil, qui peut mener à leur mort, et par conséquent à la perte de la vision. Un protocole préalablement décrit a été utilisé pour induire la dégénération rétinienne dans les souris albinos Balb/c. Les rétines ont été analysées à différents moments après la lésion par différentes techniques, aussi bien au niveau moléculaire que fonctionnel. Les résultats obtenus ont confirmé que des doses toxiques de lumière induisent la mort des photorécepteurs, mais altèrent également la voie de signalisation du VEGF, aussi bien dans la neuro-rétine que dans le reste de l'oeil, contenant l'épithélium pigmentaire (EP), et suggérant un flux de VEGF provenant de ΙΈΡ en direction de la neuro-rétine. Simultanément, il se produit une altération de l'intégrité de la barrière hémato-rétinienne externe, menant à la fuite de protéine telle que l'albumine, provenant de la choroïde et retrouvée dans les compartiments extravasculaires de la rétine, telle que dans la couche des photorécepteurs.Pour déterminer l'importance et le rôle du VEGF, un vecteur lentiviral codant pour un anticorps neutralisant dirigée contre tous les isoformes du VEGF a été développé (LV-V65). La bio-activité de ce vecteur a été testé et validée dans un modèle de laser, connu pour induire des néovascularisations choroïdiennes chez la souris suite à l'augmentation du VEGF. Ce vecteur a ensuite été utilisé dans le modèle de dégénération induite par la lumière. Les résultats des électrorétinogrammes, les mesures de l'acuité visuelle et les analyses histologiques ont montré que l'injection du LV-V65 contribue à la maintenance de photorécepteurs fonctionnels. Au niveau de l'EP, l'absence d'albumine et la maintenance des jonctions cellulaires des cellules de l'EP ont démontré que l'intégrité de la barrière hémato-rétinienne externe est préservée suite au traitement.Par conséquent, tous les résultats obtenus indiquent que le VEGF est un médiateur important impliquée dans le processus de dégénération induit par la lumière et confirme le rôle cruciale de la balance entre les facteurs pro- et anti-angiogéniques dans la survie des photorécepteurs. Cette étude révèle également l'importance de l'intégrité de la barrière hémato-rétinienne et l'importance du lien fonctionnel et structurel entre l'EP et les photorécepteurs, essentiel pour la survie de ces derniers. Par ailleurs, Cette étude suggère que des dérèglements au niveau de l'équilibre du VEGF ne sont pas seulement impliqués dans la forme humide de la DMLA, comme déjà démontré dans des études antérieures, mais pourraient également contribuer et survenir dans des formes précoces de la DMLA, et par conséquent le VEGF représente une cible thérapeutique potentielle pour les maladies associées à des anomalies au niveau de l'EP.

Condition-dependent expression of melanin-based coloration in the Eurasian kestrel.

Melanin is the most common pigment in animal integuments and is responsible for some of the most striking ornaments. A central tenet of sexual selection theory states that melanin-based traits can signal absolute individual quality in any environment only if their expression is condition-dependent. Significant costs imposed by an ornament would ensure that only the highest quality individuals display the most exaggerated forms of the signal. Firm evidence that melanin-based traits can be condition-dependent is still rare in birds. In an experimental test of this central assumption, we report condition-dependent expression of a melanin-based trait in the Eurasian kestrel (Falco tinnunculus). We manipulated nestling body condition by reducing or increasing the number of nestlings soon after hatching. A few days before fledging, we measured the width of sub-terminal black bands on the tail feathers. Compared to nestlings from enlarged broods, individuals raised in reduced broods were in better condition and thereby developed larger sub-terminal bands. Furthermore, in 2 years, first-born nestlings also developed larger sub-terminal bands than their younger siblings that are in poorer condition. This demonstrates that expression of melanin-based traits can be condition-dependent.

Nonequilibrium thermodynamic fluctuations of black holes

With the aid of the Landau-Lifshitz theory for thermodynamic fluctuations we estimate and comment on the fluctuations in the rates of mass, angular momentum, and other relevant quantities of massive Schwarzschild and Kerr black holes.

Black holes from nucleating strings

We evaluate the probability that a loop of string that has spontaneously nucleated during inflation will form a black hole upon collapse, after the end of inflation. We then use the observational bounds on the density of primordial black holes to put constraints on the parameters of the model. Combining these constraints with current upper limits on the expansion rate during inflation, we conclude that the density of black holes formed from nucleating strings is too low to be observed. Also, constraints on domain wall nucleation and monopole pair production during inflation are briefly discussed.

Brane-world creation and black holes

An inflating brane world can be created from ``nothing'' together with its anti-de Sitter (AdS) bulk. The resulting space-time has compact spatial sections bounded by the brane. During inflation, the continuum of KK modes is separated from the massless zero mode by the gap m=(3/2)H, where H is the Hubble rate. We consider the analogue of the Nariai solution and argue that it describes the pair production of ``black cigars'' attached to the inflating brane. In the case when the size of the instantons is much larger than the AdS radius, the 5-dimensional action agrees with the 4-dimensional one. Hence, the 5D and 4D gravitational entropies are the same in this limit. We also consider thermal instantons with an AdS black hole in the bulk. These may be interpreted as describing the creation of a hot universe from nothing or the production of AdS black holes in the vicinity of a pre-existing inflating brane world. The Lorentzian evolution of the brane world after creation is briefly discussed. An additional ``integration constant'' in the Friedmann equation-accompanying a term which dilutes like radiation-describes the tidal force in the fifth direction and arises from the mass of a spherical object inside the bulk. In general, this could be a 5-dimensional black hole or a ``parallel'' brane world of negative tension concentrical with our brane-world. In the case of thermal solutions, and in the spirit of the AdS/CFT correspondence, one may attribute the additional term to thermal radiation in the boundary theory. Then, for temperatures well below the AdS scale, the entropy of this radiation agrees with the entropy of the black hole in the AdS bulk.

Quantum black hole entropy and newton constant renormalization

ty that low-energy effective field theory could be sufficient to understand the microscopic degrees of freedom underlying black hole entropy. We propose a qualitative physical picture in which black hole entropy refers to a space of quasicoherent states of infalling matter, together with its gravitational field. We stress that this scenario might provide a low-energy explanation of both the black hole entropy and the information puzzle.

Correlations between black holes formed in cosmic string breaking

An analysis of cosmic string breaking with the formation of black holes attached to the ends reveals a remarkable feature: the black holes can be correlated or uncorrelated. We find that, as a consequence, the number-of-states enhancement factor in the action governing the formation of uncorrelated black holes is twice the one for a correlated pair. We argue that when an uncorrelated pair forms at the ends of the string, the physics involved is more analogous to thermal nucleation than to particle-antiparticle creation. Also, we analyze the process of intercommuting strings induced by black hole annihilation and merging. Finally, we discuss the consequences for grand unified strings. The process whereby uncorrelated black holes are formed yields a rate which significantly improves over those previously considered, but still not enough to modify string cosmology. 1995 The American Physical Society.

Black holes as fundamental strings: Comparing the absorption of scalars

The recently proposed correspondence principle of Horowitz and Polchinski provides a concrete means to relate (among others) black holes with electric Neveu-SchwarzNeveu-Schwarz charges to fundamental strings and correctly match their entropies. We further test this correspondence by examining the greybody factors in the absorption rates of neutral, minimally coupled scalars by a near extremal black hole. Perhaps surprisingly, the results disagree in general with the absorption by weakly coupled strings. Though this does not disprove the correspondence, it indicates that it might not be simple in this region of the black hole parameter space.

Can extreme black Holes have (long) Abelian Higgs hair?

It has been argued that a black hole horizon can support the long-range fields of a Nielsen-Olesen string and that one can think of such a vortex as black hole "hair." In this paper, we examine the properties of an Abelian Higgs vortex in the presence of a charged black hole as we allow the hole to approach extremality. Using both analytical and numerical techniques, we show that the magnetic field lines (as well as the scalar field) of the vortex are completely expelled from the black hole in the extreme limit. This was to be expected, since extreme black holes in Einstein-Maxwell theory are known to exhibit such a "Meissner effect" in general. This would seem to imply that a vortex does not want to be attached to an extreme black hole. We calculate the total energy of the vortex fields in the presence of an extreme black hole. When the hole is small relative to the size of the vortex, it is energetically favored for the hole to remain inside the vortex region, contrary to the intuition that the hole should be expelled. However, as we allow the extreme horizon radius to become very large compared to the radius of the vortex, we do find evidence of an instability. This proves that it is energetically unfavorable for a thin vortex to interact with a large extreme black hole. This would seem to dispel the notion that a black hole can support "long" Abelian Higgs hair in the extreme limit. We show that these considerations do not go through in the near-extreme limit. Finally, we discuss the implications for strings that end at black holes, as in the processes where a string snaps by nucleating black holes.

Superconducting p-branes and extremal black holes

In Einstein-Maxwell theory, magnetic flux lines are "expelled" from a black hole as extremality is approached, in the sense that the component of the field strength normal to the horizon goes to zero. Thus, extremal black holes are found to exhibit the sort of ¿Meissner effect¿ which is characteristic of superconducting media. We review some of the evidence for this effect and present new evidence for it using recently found black hole solutions in string theory and Kaluza-Klein theory. We also present some new solutions, which arise naturally in string theory, which are non-superconducting extremal black holes. We present a nice geometrical interpretation of these effects derived by looking carefully at the higher dimensional configurations from which the lower dimensional black hole solutions are obtained. We show that other extremal solitonic objects in string theory (such as p-branes) can also display superconducting properties. In particular, we argue that the relativistic London equation will hold on the world volume of ¿light¿ superconducting p-branes (which are embedded in flat space), and that minimally coupled zero modes will propagate in the adS factor of the near-horizon geometries of "heavy," or gravitating, superconducting p-branes.

Vortices and extreme black holes: The question of flux expulsion

It has been claimed that extreme black holes exhibit a phenomenon of flux expulsion for Abelian Higgs vortices, irrespective of the relative width of the vortex to the black hole. Recent work by two of the authors showed a subtlety in the treatment of the event horizon, which cast doubt on this claim. We analyze in detail the vortexextreme black hole system, showing that, while flux expulsion can occur, it does not do so in all cases. We give analytic proofs for both expulsion and penetration of flux, in each case deriving a bound for that behavior. We also present extensive numerical work backing up, and refining, these claims, and showing in detail how a vortex can end on a black hole in all situations. We also calculate the back reaction of the vortex on the geometry, and comment on the more general vortexblack hole system.