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Curved- and flat-diffraction crystal spectrographs were developed to collect x-ray spectra from high-atomic-number elements (cadmium-rare earths) in the 5-17-Å region. The plasma source was generated by the 24-beam, frequency-tripled light of the OMEGA laser system. The spectral patterns were identified with the aid of atomic structure calculations and from Moseley plots of isoelectronic sequences. The Ne-like (third-order diffraction) and Na-like ionization stages were observed in the Cd and Sn spectra. The rare-earth spectra were predominantly 3d-4p, 4f transitions over a range of ionization stages involving the M shell. Calibration spectra were obtained with L-series transitions from Fe and Cu targets and K lines from Si plasma excited in the glass supporting stalk. [ABSTRACT FROM AUTHOR]

Introduction: More than 30 million adults are released from incarceration globally each year. Many experience complex physical and mental health problems, and are at markedly increased risk of preventable mortality. Despite this, evidence regarding the global epidemiology of mortality following release from incarceration is insufficient to inform the development of targeted, evidence-based responses. Many previous studies have suffered from inadequate power and poor precision, and even large studies have limited capacity to disaggregate data by specific causes of death, sub-populations or time since release to answer questions of clinical and public health relevance., Objectives: To comprehensively document the incidence, timing, causes and risk factors for mortality in adults released from prison., Methods: We created the Mortality After Release from Incarceration Consortium (MARIC), a multi-disciplinary collaboration representing 29 cohorts of adults who have experienced incarceration from 11 countries. Findings across cohorts will be analysed using a two-step, individual participant data meta-analysis methodology., Results: The combined sample includes 1,337,993 individuals (89% male), with 75,795 deaths recorded over 9,191,393 person-years of follow-up., Conclusions: The consortium represents an important advancement in the field, bringing international attention to this problem. It will provide internationally relevant evidence to guide policymakers and clinicians in reducing preventable deaths in this marginalized population., Key Words: Mortality; incarceration; prison; release; individual participant data meta-analysis; consortium; cohort., Competing Interests: Statement of Conflicts of Interest: SF is on the UK’s Independent Advisory Board on Deaths in Custody. PC has received grants from Abbvie and Echosens to conduct research relating to prison health. IB has received royalties from Uptodate for educational content on health care for incarcerated persons. All other authors report no conflicts of interest.

To show how apertures affect measurements of the circularly polarized components of light scattered to a detector, we develop two methods of averaging the V and I Stokes parameters over a circular aperture that collects light scattered from an optically active sphere. One method uses a two-dimensional numerical integration that is appropriate for small apertures, and the other gives analytical expressions for scattering into a solid angle of any size. We identify the aperture locations that, independent of aperture size, give an average V (and an effective degree of circular polarization) of zero for scattering from an optically inactive sphere and of nonzero for scattering from an optically active sphere.

A determination of the viability of an endospore detection technique using terbium dipicolinate photoluminescence in the presence of other chemical and biological materials was performed. The compounds and organisms examined, possible environmental constituents, covered three broad categories:  organic compounds, inorganic compounds, and biological materials. Each substance was tested for a false positive, which occurs if the intrinsic terbium photoluminescence is enhanced in the absence of a bacterial endospore. The detection technique was also investigated for false negatives, which occur if a known positive endospore signal is inhibited significantly. Although several materials may give rise to false negative signals, none caused a false positive signal to be observed.

Two regression techniques, a multivariate technique and a subtracted component technique, were applied to two-wavelength response functions of mixtures of terbium (III) dipicolinate and insoluble bacterial particles. Two wavelength pairs were analyzed: a pair of neighboring wavelengths (450/490 nm) and a pair of widely spaced wavelengths (490/622 nm). The analysis shows that two emission-wavelength spectra from terbium-treated endospores can be distinguished from the vegetative bacteria spectrum above a limit of detection for endospores, which depends on the regression algorithm used to analyze the spectra. The subtracted component method for the neighboring wavelength pair had far lower limits of detection than the other methods.

Light scattered from optically active spheres was theoretically analyzed for biodetection. The circularly polarized signal of near-forward scattering from circularly dichroic spheres was calculated. Both remote and point biodetection were considered. The analysis included the effect of a circular aperture and beam block at the detector. If the incident light is linearly polarized, a false signal would limit the sensitivity of the biodetector. If the incident light is randomly polarized, shot noise would limit the sensitivity. Suggested improvements to current techniques include a beam block, precise angular measurements, randomly polarized light, index-matching fluid, and larger apertures for large particles.

Rank annihilation-factor analysis is potentially the best method of analyzing fluorescence lidar returns because of the following capability. Rank annihilation can recognize a fluorescence signal of a component that is hidden by a large fluorescence background without a spectrum of that background. Theoretical models were developed to analyze the effectiveness of rank annihilation-factor analysis in the interpretation of lidar returns. Interferents such as background fluorescence, photon-counting noise, sky radiance, and atmospheric extinction degraded the lidar-return spectra in numerical simulations. The rank annihilation-factor analysis detection algorithm was most severely biased by the combination of photon-counting noise and sky radiance. Rank annihilation calculations were also compared with calculations done by two other detection algorithms: finding peak wavelengths and the least-squares technique. Rank annihilation is better than both techniques.

Experiments were carried out to seek evidence of an interaction between two viroid RNAs introduced to tomato plants in the same inoculum. At the level of symptom expression, the severe isolate of potato spindle tuber viroid (PSTV) dominated the mild isolate. Seventy-five percent of the plants inoculated with a 100-fold excess of the mild isolate developed unattenuated symptoms of severe disease. Other experiments revealed that infectious RNA molecules transcribed from cloned DNA templates containing PSTV sequences reduced the level of hop stunt viroid (HSV) RNA present in nucleic acid extracts of plants which had been inoculated with a mixture of dimeric plus-strand transcripts of these two viroids. Plants inoculated with dual transcripts--containing two copies of PSTV linked to two copies of HSV--developed characteristic symptoms of severe PSTV. Dot hybridization demonstrated that only PSTV replicated to detectable levels in these plants. A likely interpretation of these results is that the HSV portion of the dual transcripts failed to replicate because of interference from PSTV. These results raise questions about how the process of viroid replication is related to symptom expression, and lead to suggested models for the effect of viroid-like RNAs in cells under both normal and pathogenic circumstances.

A full-length cloned cDNA insert containing the sequence of potato spindle tuber viroid (PSTV) was dimerized and placed in the plasmid vector pSP65 adjacent to a promoter for bacteriophage SP6 RNA polymerase. In vitro transcription of this region yielded a single linear RNA chain 760 bases in length containing two copies of PSTV RNA with about 20 bases of vector sequence at each end. Bioassay on tomato plants revealed that this transcript has infectivity comparable to that of PSTV itself, yielding circular progeny RNAs indistinguishable from PSTV grown in vivo Comparative RNA fingerprinting analysis revealed that the viroid sequence in the dimeric transcript breeds true (compared to control viroid strains of different sequence grown in parallel) but loses the vector-specific sequences during growth in plants. Incubation of 32P-labeled dimeric PSTV RNA at neutral pH and 39 degrees gave a 1-5% yield of three RNA segments, one comigrating with unit-length linear PSTV and two smaller fragments. Reaction of the unit-length cleavage product with wheat germ RNA ligase gave a high yield of circular molecules indistinguishable from PSTV circles arising in vivo, suggesting that the cleavage reaction yields 2',3' cyclic phosphate termini and could represent a part of the in vivo PSTV replication cycle.

We have developed a protocol for efficiently introducing macromolecules into Drosophila tissue culture cells using liposomes. By carefully adjusting the fusion parameters, conditions have been established to routinely encapsulate 15-30% of the starting material into liposomes and to introduce 20-30% of the liposome-encapsulated material into the cells during a 30-minute fusion period. Essentially, all of the cells receive material from the liposomes and 10(9) cells can be fused at once. The fusion does not have any measureable effect on cell viability as assayed by trypan blue exclusion, growth rate, and cell morphology. We have utilized this technique to introduce radioactive RNAs into nonradioactive cells, thus enabling the behavior of the introduced RNAs to be followed unambiguously. Liposome-introduced small nuclear RNAs (snRNAs) are stable in the cell for at least 25 hours (approximately two cell generations), with 80% of the radioactivity remaining trichloroacetic acid (TCA) precipitable and the gel electrophoresis pattern remaining essentially unchanged. This is in contrast to liposome-introduced cytoplasmic RNAs, which are only 20% TCA precipitable after the first hour. In the cell, the introduced snRNAs attain a 10-35-fold higher concentration in the nucleus than the cytoplasm. Nuclear accumulation is not seen with Drosophila tRNA or 5S RNA, both of which attain the same nuclear as cytoplasmic RNA concentration.