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The linear Cauchy problem [image omitted]  for [image omitted]  with a linear pseudo-differential operator L(D) whose symbol is analytic in a domain [image omitted]  is discussed in the framework of spaces [image omitted]  and [image omitted]  The space [image omitted]  is the space of tempered distributions whose Fourier transform is supported by a subset of G, and [image omitted]  is its dual space. Theorems of existence and uniqueness are presented and methods of approximating the solutions are developed. Applications to some concrete problems are described.

The singular values sn(K) of the Volterra integral operator[image omitted] in L2(0,1) are proved to have the asymptotics[image omitted] when [image omitted]  and h(x,t) is a smooth enough function with respect to the variable x and square integrate. The asymptotics of the singular values of the fractional integral operator [image omitted]  (the case [math004]) is given more precisely by[image omitted]

The Abel integral operator [image omitted]  where α> 0, 0 < a ≤∞u εLp(0,a), is considered. Suppose that fis such that [image omitted] . A regularized approximate solution u€ of the operator equation [image omitted]  can then be computed by using the Grünwald-Letnikov difference operator of order α (see [5], p. 289). This regularized solution satisfies the error estimate [image omitted]  provided that u' exists and u'εLp(0,a),α>1u(0) = 0 and the error estimate [image omitted]  provided that u belongs to the space of Hölder functions [image omitted]  of order λ (see [5], p. 200).

Many bacteria are able to synthesize polyesters of hydroxyalkanoic acids (PHA), which occur as insoluble cytoplasmic inclusions in the cell and can contribute significantly to the cellular dry matter. More than 100 different hydroxyalkanoic acids have been detected as constituents in PHA. This article summarizes strategies and possibilities to obtain these biodegradable and thermoplastic/elastomeric polymers by fermentation of wild-type bacteria as well as of mutants and recombinant strains from renewable resources, waste substrates or special precursor substrates. In addition,in vitrobiosynthesis of PHA employing the purified polymerizing enzyme (PHA synthase) is described. Throughout analysis and cloning of the bacterial PHA biosynthesis genes enabled scientists to also establish this pathway in non-PHA producing eukaryotic organisms such as yeast, plants and animals. This will allow new processes for cheap and economic production of PHA.

After analyzing the general linear equation of diffusion (of a substance or of energy) with source term and given influx across the boundary we describe a method for constructing explicit and implicit conservative difference schemes which also preserve nonnegativity. We call a scheme “conservative” if via a convenient sum-analogue it does exactly imitate the conservation of a substance or energy. We concretize this method for the spatially two-dimensional heat equation in a rectangle with given influx. We also present a conservative implicit scheme with alternating directions

Open lung biopsy is performed in patients with congenital heart disease to determine the suitability for surgical correction. Controversy exists as to whether arterial density can be graded with certainty. We studied the influence on the grading (Heath-Edwards) of two morphometric techniques. Lung tissue from 14 controls and biopsy specimens from 80 patients with atrial septal defect (n=10), ventricular septal defect (n=27), complete atrioventricular canal (n=27), miscellaneous lesions (n=8) and tetralogy of Fallot (n=8) were analyzed with a planimetric method. Additionally, wall thickness was determined in 52 patients by distance measurements. The ratio of alveoli/arteries per area of lung tissue was measured. Medial thickness was “increased” on distance measurements in 15% of the cases where planimetric data showed normal wall thickness. The ratio of alveoli/arteries varied up to 43% from the mean. Hemodynamic data obtained at a median (range) time of 2 months (1 day to 18 months) before the operation did not correlate with morphologic findings. In 27 patients hemodynamic data were recorded at a median time of 1 year (3 days to 44 months) after the operation. Intimal fibrosis occupying more than 1 0% of the vessel lumen was associated with persistent high pulmonary vascular resistance. We conclude that morphometric techniques are useful to determine the degree of fibrosis in advanced vascular lesions. Arterial density cannot be determined in biopsy specimens with adequate certainty.

A study of second-year medical students was conducted to determine if selected personal and behavioral variables are related to the perceived amount of stress. Medical students from seven medical schools (N = 555) responded to a mailed questionnaire that assessed their degree of academic, personal, and professional stress. Factors that significantly related to amount of academic stress were general satisfaction with life, sex of student, physical activity, alcohol use, hours of sleep per night, and total number of recent losses and misfortunes. Factors that significantly related to amount of personal stress were general satisfaction with life, sex of student, drug use, number of sensation-seeking sports and total number of recent losses and misfortunes. Although measured, professional stress was not considered an important component of a second-year medical student's educational experience.

ABSTRACTAlthough PCR analysis is a sensitive test for detection of human papillomavirus (HPV) in the cervix, the proportion of cases of cervical dysplasia missed, or the false-negative rate, has been unknown. We determined the accuracy of PCR analysis for HPV DNA as a predictor of HPV-related cervical lesions in a cross-sectional study of sexually active women, aged 18 to 50 years, from the University of Michigan Family Medicine HPV study. Of 133 eligible participants, 41 underwent colposcopy because of a positive result for HPV of the cervix by the PCR method and 92 underwent screening colposcopy with biopsy prior to knowing the HPV PCR results. Twenty-four of those screened were subsequently found to also be HPV DNA positive. In those found to be HPV positive, histological studies revealed the presence of condyloma or cervical intraepithelial neoplasia in 16 women (24.6%) and changes suggestive of condyloma in 5 (7.6%). No HPV-negative woman had an abnormal biopsy or cytology report (P= 0.000001). The false-negative rate (1 - sensitivity) for HPV PCR analysis for detection of the presence of a cervical HPV-related lesion was 0% (95% confidence interval, 0 to 0.047), and the specificity was 60.7%. In summary, PCR analysis for HPV DNA had a very low false-negative rate for predicting HPV-related lesions of the cervix in a community-based population. This supports the validity of using the absence of HPV at the cervix, as determined by PCR testing, as an inclusion criterion for patients in control groups in studies dealing with low-grade cervical lesions.

There have been several reports of right-to-left shunting through patent foramen ovale (PFO) after implantation of a left ventricular assist device (LVAD). The atrial pressure changes after assist implantation leading to revelation of undetected PFOs may cause severe systemic hypoxemia. A percutaneous closure approach has been shown to be an adequate therapy option in patients with LVAD. We report a successful interventional occlusion of a PFO with right-to-left shunt in a patient with biventricular HeartWare® ventricular assist device (HVAD) support.

AbstractPercutaneous edge-to-edge mitral valve repair using the MitraClipTMhas not been used in children. The patient in this reported case was a 15-year-old male adolescent who presented postnatally with severe aortic valve stenosis and dysplasia of the mitral valve. The boy underwent surgical valvuloplasty at the age of 3 months and an aortoventriculoplasty with three re-operations. At the age of 15 years, he developed severe mitral valve regurgitation. Owing to high surgical risks, a MitraClipTMwas implanted with a reduction of mitral regurgitation from grade 4+ to 2+, translating into a rapid clinical improvement.

Anomalous drainage of the right superior caval vein into the morphologically left atrium as an isolated cardiac malformation is a rare anomaly. Most patients present with cyanosis. Thus far, about 20 cases have been reported in the literature. We report a case of cyanosis due to this malformation in a male neonate, which was complicated by the meconium aspiration syndrome. The malformation was diagnosed by echocardiography and cardiac catheterization. Surgery resulted in complete recovery.

Advises individuals and families on how to protect themselves from criminals while at home, while driving, walking or doing other activities.

Muckenthaler: Novartis: Research Funding. Bourquin:Amgen: Other: Travel Support. Kulozik:bluebird bio: Consultancy, Honoraria.

AbstractA newborn presented with an aorto-right ventricular tunnel, a defect connecting the left aortic sinus to the right ventricle. The patient underwent repair on 4th day of life.

Vulvodynia, or chronic vulvar pain, which often is accompanied by dyspareunia, is quite prevalent and difficult to treat effectively. Neuropathic pain typically is described, and findings that sensitization to pain is increased at sites removed from the vulva suggest that systemic treatment for nerve hypersensitivity might prove helpful. Today antidepressants, especially tricyclic antidepressants (TCAs) such as amitriptyline, are commonly used in low dosage to treat vulvodynia. This retrospective study included 271 affected women, 209 of whom were initially treated with a TCA. Amitriptyline was administered to 183 women, while smaller numbers received desipramine or other TCAs. A total of 162 women, including 122 started on a TCA, were followed up for a median time of 3.2 months. The typical starting TCA dose was 25 mg each night (or 10 mg for elderly patients), and the maximum nightly dose was 225 mg. Patients rated their pain on a 0-to-10 scale.

The diffraction of light is considered for a plane screen with an open bounded aperture. The corresponding solution behind the screen is given explicitly in terms of the Fourier transforms of the tangential components of the electric boundary field in the aperture. All components of the electric as well as the magnetic field vector are considered. We introduce solutions with global finite energy behind the screen and describe them in terms of two boundary potential functions. This new approach leads to a decoupling of the vectorial boundary equations in the aperture in the case of global finite energy. For the physically admissible solutions, that is, the solutions with local finite energy, we derive a characterisation in terms of the electric boundary fields.