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1.
Article in German | MEDLINE | ID: mdl-20976429

ABSTRACT

This study enrolled mentally ill mothers from Mecklenburg-Vorpommern, Germany, with children between the ages of 0 and 3 years. Using different self and expert ratings, psychological symptoms, social support, parental stress, and behavior of the children were assessed. Teenage mothers and adult mothers were compared using the mean values of the data. The data of 104 mothers were included; 46.1% of the mothers were younger than 20 years of age when they gave birth. All mothers show a variety of psychological problems. While adult mothers had significantly more affective and anxiety disorders, teenage mothers had significantly more eating disorders and sexual abuse in their histories. Young mothers reported subjectively significantly less social support and more parenting stress than older mothers. The children in both subgroups are described as unremarkable. More than 80% of the mothers had at least one contact with youth welfare, a general practitioner, or a pediatrician, while only 23% used psychiatric or psychological help. The data show a high level of stress in both groups and there is a great need for support from the medical sector as well as from youth welfare.


Subject(s)
Mental Disorders/epidemiology , Mother-Child Relations , Mothers/statistics & numerical data , Stress, Psychological/epidemiology , Substance-Related Disorders/epidemiology , Adolescent , Adult , Age Distribution , Child, Preschool , Comorbidity , Female , Germany/epidemiology , Humans , Incidence , Infant , Infant, Newborn , Male , Mental Disorders/psychology , Mothers/psychology , Pilot Projects , Risk Assessment , Risk Factors , Stress, Psychological/psychology , Substance-Related Disorders/psychology , Young Adult
2.
Appl Opt ; 34(28): 6389-92, 1995 Oct 01.
Article in English | MEDLINE | ID: mdl-21060485

ABSTRACT

The development of multilayer mirror technology capable of operating in the range of 3-30 nm and the construction of thin membranes with excellent uniformity and strength have made it possible to design and implement a Mach-Zehnder interferometer operating at 15.5 nm. We have tested this interferometer by using a soft x-ray laser as a source, and we show its use in probing high-density plasmas.

3.
Science ; 266(5188): 1213-5, 1994 Nov 18.
Article in English | MEDLINE | ID: mdl-17810262

ABSTRACT

Ultrahigh-resolution three-dimensional images of a microscopic test object were made with soft x-rays collected with a scanning transmission x-ray microscope. The test object consisted of two different patterns of gold bars on silicon nitride windows that were separated by approximately 5 micrometers. Depth resolution comparable to the transverse resolution was achieved by recording nine two-dimensional images of the object at angles between -50 and +55 degrees with respect to the beam axis. The projections were then combined tomographically to form a three-dimensional image by means of an algorithm using an algebraic reconstruction technique. A transverse resolution of approximately 1000 angstroms was observed. Artifacts in the reconstruction limited the overall depth resolution to approximately 6000 angstroms; however, some features were clearly reconstructed with a depth resolution of approximately 1000 angstroms.

4.
Science ; 265(5171): 514-7, 1994 Jul 22.
Article in English | MEDLINE | ID: mdl-17781311

ABSTRACT

A soft x-ray laser (wavelength lambda = 15.5 nanometers) was used to create a moiré deflectogram of a high-density, laser-produced plasma. The use of deflectometry at this short wavelength permits measurement of the density spatial profile in a long-scalelength (3 millimeters), high-density plasma. A peak density of 3.2 x 10(21) per cubic centimeter was recorded.

5.
Science ; 258(5080): 269-71, 1992 Oct 09.
Article in English | MEDLINE | ID: mdl-1411525

ABSTRACT

The development of high brightness and short pulse width (< 200 picoseconds) x-ray lasers now offers biologists the possibility of high-resolution imaging of specimens in an aqueous environment without the blurring effects associated with natural motions and chemical erosion. As a step toward developing the capabilities of this type of x-ray microscopy, a tantalum x-ray laser at 44.83 angstrom wavelength was used together with an x-ray zone plate lens to image both unlabeled and selectively gold-labeled dried rat sperm nuclei. The observed images show approximately 500 angstrom features, illustrate the importance of x-ray microscopy in determining chemical composition, and provide information about the uniformity of sperm chromatin organization and the extent of sperm chromatin hydration.


Subject(s)
Cell Nucleus/ultrastructure , Lasers , Microscopy/methods , Spermatozoa/ultrastructure , Animals , Cell Fractionation , Chromatin/ultrastructure , DNA/ultrastructure , Epididymis/cytology , Immunohistochemistry , Male , Rats , X-Rays
6.
Opt Lett ; 17(10): 754-6, 1992 May 15.
Article in English | MEDLINE | ID: mdl-19794620

ABSTRACT

High-brightness and short-pulse-width ( approximately 200 ps) x-ray lasers offer biologists the possibility of high-resolution three-dimensional imaging of specimens in an aqueous environment without the blurring effects associated with natural motions. As a first step toward developing the capabilities of this type of x-ray microscopy we have used a tantalum x-ray laser (lambda = 4.483 nm) together with an x-ray zone plate lens to image a test pattern. The observed image shows a detector-limited resolution of approximately 75 nm and paves the way to three dimensional biological imaging with high spatial resolution (20-30 nm).

7.
Appl Opt ; 28(16): 3397-404, 1989 Aug 15.
Article in English | MEDLINE | ID: mdl-20555712

ABSTRACT

The choice of an optimal wavelength for soft x-ray holography is discussed, based on a description of scattering by biological structures within an aqueous environment. We conclude that wavelengths slightly longer than the 43.7-A carbon K-edge provide a good trade off between minimizing the necessary source power and the dose absorbed by the sample and maximizing the penetrability of the x-rays through wet samples. This differs from the previous notion that wavelengths within the water window (between 23.2 A and 43.7 A) would be the best for holography. The problem of motion resulting from the absorption of x rays during a short exposure is described. The possibility of using ultrashort exposures in order to capture the image before motion can compromise the resolution is explored. The impact of these calculations on the question of the feasibility of using an x-ray laser for holography of biological structures is discussed.

8.
Appl Opt ; 28(23)1989 Dec 01.
Article in English | MEDLINE | ID: mdl-20555973

ABSTRACT

This Letter points out several errors made in the printing of the original submission.

9.
10.
Appl Opt ; 27(24): 5022-5, 1988 Dec 15.
Article in English | MEDLINE | ID: mdl-20539693

ABSTRACT

We report the first time-resolved measurements of emission from a double-pass soft x-ray laser cavity. In these experiments the output signal from a selenium x-ray laser had two temporal components clearly identifiable as the single- and double-pass emission, with the double-pass amplified signal more intense than the single pass. In addition to an unequivocal demonstration of double-pass amplification of soft x rays, the data provide information about of the time-dependent gain in these x-ray laser media, suggesting an effective gain-length profile which rises more slowly and falls-off more rapidly than predicted by state of the art hydrodynamics and kinetics codes.

11.
Science ; 238(4826): 517-9, 1987 Oct 23.
Article in English | MEDLINE | ID: mdl-17809616

ABSTRACT

An x-ray hologram was made by means of an x-ray laser and a laser-quality near normal incidence x-ray mirror. The high brightness and large coherence lengths of x-ray lasers now offer the potential for in vitro three-dimensional high-resolution holographic images of dynamically varying biological microstructures.

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