Effects of beta-carotene and other factors on outcome of cervical dysplasia and human papillomavirus infection

OBJECTIVES: The age-dependence of the development of ventricular arrhythmias was studied in German shepherd dogs with inherited ventricular arrhythmias and sudden death. BACKGROUND: A colony of German shepherd dogs has been established that exhibit inherited ventricular arrhythmias and sudden death. The incidence of arrhythmias increases with age. Because ventricular tachycardia is associated with bradycardia, it was hypothesized that the increased incidence of arrhythmias was related to age-dependent slowing of heart rate. METHODS: Arrhythmia counts and RR intervals were measured from serial ambulatory ECG recordings obtained in 71 dogs (1-48 weeks). In addition, 19 dogs were challenged with phenylephrine (10 micrograms/kg i.v.) at 15, 28, and 45 weeks of age, 10 dogs were challenged with epinephrine (1 microgram/kg i.v.) at 3, 5, 7, 9, 11, 18, and 28 weeks of age, and 10 dogs were challenged at 28 weeks with epinephrine (2.5 micrograms/kg i.v.), before and after propranolol (0.5 mg/kg i.v.). RESULTS: The incidence and severity of ventricular arrhythmias increased between 7 and 28 weeks of age and decreased between 28 and 44 weeks of age. The age-dependent increase in the incidence of ventricular tachycardia was associated with age-dependent reductions in sinus rate. Baroreflex-mediated slowing of the heart rate unmasked arrhythmias in young animals that did not spontaneously display arrthythmias and exacerbated existing arrhythmias in older animals. However, the magnitude of baroreflex-induced bradycardia was similar from 7-18 weeks of age, yet the incidence of arrhythmias increased progressively. Moreover, the waning of ventricular arrhythmias in older animals was not associated with more rapid sinus rates. CONCLUSION: The risk for sudden death in dogs with inherited ventricular arrhythmias increases with age in part because of age-dependent slowing of heart rate and in part because of other heart-rate-independent factors. The correspondence between the development of ventricular tachycardia and sinus pauses is consistent with the hypothesis that ventricular arrhythmias are initiated by early afterdepolarization-induced triggered activity.     

The Generic Bilinear Calibration-Estimation Problem

We identify a very general, recurring pattern in a number of well known problems in biological and machine vision. Many problems are of a peculiar double-sided nature: One attempts to estimate certain properties of the environment using a certain type of equipment and simultaneously one attempts to calibrate the same equipment on the structure of the environment. At first sight this appears the kind of the chicken and the egg problem that might well prove to be insoluble. However, due to basic constraints that universally apply (e.g., the world is only three-dimensional), a solution—up to a certain class of ambiguity transformations—often exists. The more complicated the problem is, the less important the remaining ambiguity will be, at least in a relative sense. Many well known problems are special in that they can be cast in bilinear form, sometimes after transformation or the introduction of dummy variables. Instances include photometric stereo, photometric estimations (e.g., of lightness), local (differential) image operators, a variety of photogrammetric problems, etc. It turns out that many of these problems—and together these make up a large fraction of the generic problems in machine vision today—can be cast in a simple universal framework. This framework enables one to handle arbitrarily large (that is, not minimal, consistent configurations), noisy (thus inconsistent) date sets automatically. The level at which prior information (either of a deterministic or a statistical nature) is used (assumptions such as constant albedo, rigidity, uniform distributions, etc.) is clearly separated as an additional, typically nonlinear, stage.     

Interactions in the complement-mediated lysis of blood group AB erythrocytes sensitized simultaneously with anti-A and anti-B monoclonal antibodies

The lysis of group AB erythrocytes by human complement was studied by different anti-A and anti-B IgM monoclonal antibodies (mabs) in a 51Cr-release assay. The concentration of membrane-bound immunoglobulin was detected by ELISA, and the amount of C1q and C3 bound to sensitized red cells was measured by using purified, 125I-labelled molecules. We have demonstrated that there is an exponential relationship between the concentration of the sensitizing IgM mabs and C1q binding to the sensitized AB cell. The efficiency of binding was related to the number of antibodies bound; thus, anti-A sensitized cells bound 3-6 times more C1q than anti-B sensitized cells did. AB cells, on the other hand, bound similar amounts of C3 whether anti-A or anti-B was present. The lytic efficiencies of the various IgM mabs during short incubation times were different, suggesting that the complement activation rates vary widely with different antibodies on the AB cell membrane. The binding of C1q to an antibody-sensitized target activates a cascade, whose components may migrate away from the sensitizing antibody; interactions between the activation processes generated by the anti-A and anti-B antibodies may thus occur. Choosing appropriate pairs of anti-A and anti-B mabs for the simultaneous sensitization of AB cells has indeed resulted in stimulation in some and inhibition in other combinations of mabs. It is suggested that stimulation is observed when the activated intermediates are produced in excess, whereas inhibition occurs when a shortage of activated intermediates prevents mutual utilization.     

Use of a subcutaneous glucose sensor to detect decreases in glucose concentration prior to observation in blood

The development of a hypoglycemic alarm system using a subcutaneous glucose sensor implies that a decrease in blood glucose is rapidly followed by a decrease in the signal generated by the sensor. In a first set of experiments the linearity and the kinetics of the response of sensors implanted in the subcutaneous tissue of normal rats were investigated during a progressive increase in plasma glucose concentration: the sensitivities determined between 5 and 10 mM and between 10 and 15 mM were not significantly different, and a 5-10 min delay in the sensor's response was observed. In a second set of experiments, performed in diabetic rats, the kinetics of the decrease in subcutaneous glucose concentration following insulin administration was monitored during a decrease in plasma glucose level, from 15 to 3 mmol/L. During the 20 first min following insulin administration, the sensor monitored glucose concentration in subcutaneous tissue with no lag time. Subsequently, the decrease in the estimation of subcutaneous glucose concentration preceded that of plasma glucose. This phenomenon was not observed when the same sensors were investigated in vitro during a similar decrease in glucose concentration and may be due to a mechanism occurring in vivo, such as the effect of insulin on glucose transfer from the interstitial space to the cells surrounding the sensor. It reinforces the interest of the use of implantable glucose sensors as a part of a hypoglycemic alarm.     

Das Blockieren einer Internet-Seite als strafbare Nötigung

Zusammenfassung  Aus der Sicht eines informationstechnischen Laien scheinen Denial of Service-Angriffe mit Online-Demonstrationen in keinem Zusammenhang zu stehen. Das Gegenteil ist der Fall, wenn durch derartige Angriffe der Anbieter einer Webseite buchst?blich lahm gelegt wird. Ob die an sich lautere Intention einer kritischen Meinungs?u?erung derartige Angriffe rechtfertigen kann, ist fraglich und besch?ftigt die Justiz. Der Verfasser dieses Beitrages bewertet den Sachverhalt eines Denial-of-Service-Angriffes strafrechtlich. Dr. jur. Jan Eichelberger, LL.M.oec. Rechtsreferendar am Kammergericht Interessenschwerpunkte im Gewerblichen Rechtsschutz, im Kapitalmarktrecht und im Recht der neuen Medien     

PROBABILISTIC MODELLING OF LIGNIN LIQUEFACTION

The results of the thermal and catalytic reactions of lignin model compounds are used in the a priori prediction of its liquefaction. Lignin was defined probabilistically as an ensemble of single ring aromatics with substituents on each of their six ring positions. Elements in a substituent vector x¹, for each ring position i, were matched into all possible combinations to describe lignin. Initial number fractions, or probabilities, for each vector element were ascertained through inspection of lignin structural data. The reaction of lignins altered the probabilities within each substituent vector, and reaction products were also calculated by matching all combinations of vector elements for each ring position. Model compound results provided the identities and rates of change of vector elements.

This simulation of lignin liquefaction predicted the yields of permanent gases, aqueous liquids, single- and two-ring phenolic products, and a carbonaceous residue. The impact of the distribution of oligomeric sizes on catalyst effectiveness was probed.     

The Construction of Minimal DNA Expressions

We describe a formal language/notation for DNA molecules that may contain nicks and gaps. The elements of the language, DNA expressions, denote formal DNA molecules. Different DNA expressions may denote the same formal DNA molecule. We analyse the shortest DNA expressions denoting a given formal DNA molecule. We determine lower bounds on their lengths and explain how we construct these minimal DNA expressions.     

A unified approach to superresolution and multichannel blind deconvolution.

This paper presents a new approach to the blind deconvolution and superresolution problem of multiple degraded low-resolution frames of the original scene. We do not assume any prior information about the shape of degradation blurs. The proposed approach consists of building a regularized energy function and minimizing it with respect to the original image and blurs, where regularization is carried out in both the image and blur domains. The image regularization based on variational principles maintains stable performance under severe noise corruption. The blur regularization guarantees consistency of the solution by exploiting differences among the acquired low-resolution images. Several experiments on synthetic and real data illustrate the robustness and utilization of the proposed technique in real applications.