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Ziel der Studie: Uberpruft wurde, inwiefern sich das berufsorientierte Therapiegeschehen in norddeutschen Rehabilitationszentren 2014 im Vergleich zu 2012 verandert hat, inwiefern sich das Leistungsgeschehen in herkommlicher medizinischer Rehabilitation (MR) und medizinisch-beruflich orientierter Rehabilitation (MBOR) unterschied, und, inwiefern die im Anforderungsprofil zur Durchfuhrung der MBOR empfohlenen Therapieumfange 2014 umgesetzt wurden. Methodik: Personen, die 2014 in der MBOR bzw. der herkommlichen medizinischen Rehabilitation behandelt wurden, wurden mittels Propensity Scores mit vergleichbaren Personen aus 2012 gematcht. Ergebnisse: Die 2014 in der MBOR behandelten Personen erhielten mehr berufsorientierte Therapien als vergleichbare Personen aus 2012 (13,5 vs. 2,5 h) und mehr als die zeitgleich in der MR behandelten Personen (13,5 vs. 1,2 h). Eine 30-minutige Sozialberatung, 180-minutige berufsbezogene Gruppen und ein 360-minutiges Arbeitsplatztraining wurden fur 93,8, 82 bzw. 41% der in 2014 in der MBOR behandelten Personen realisiert. Schlussfolgerung: Die in den norddeutschen Einrichtungen implementierten medizinisch-beruflich orientierten Rehabilitationsprogramme bilden die Empfehlungen des Anforderungsprofils weitgehend ab.

In this study, we investigated the rate and pattern of expansion of a non-native eelgrass, Zostera japonica, in relation to the distribution of the native eelgrass Zostera marina in a coastal estuary of the northeastern Pacific Ocean. The distributions of the Zostera congeners were monitored between 1997 and 2014 in Yaquina Estuary on the central Oregon coast, USA, using digital classification of color infrared aerial photographs and ground surveys. Correction factors for seasonal variations in cover were obtained to normalise the annual photo survey results to a common date (mid-August). Major expansions in the distributions of Z. japonica meadows over most of the 17-year study period were observed. However, there was no indication that the large (∼1500%) increase in areal extent of Z. japonica in the lower estuary between 1997 and 2007 was accompanied by a change in areal extent of the native Z. marina in this system.

GABI ist ein Kooperationsprojekt zwischen einem Maschinenbau-Unternehmen und einer Reha-Klinik, in dem Mitarbeitern mit gefahrdeter beruflicher Integration eine somatische und psychosomatische Diagnostik angeboten wird mit dem Ziel, konkrete Masnahmen abzuleiten. Dazu gehort ein standardisierter Profilvergleich zwischen Arbeitsplatzanforderungen und tatsachlichem Leistungsvermogen auf der Basis von IMBA/MARIE und EFL. Alle bisher eingeschlossenen 12 Teilnehmer konnten in Betrieb und Arbeit gehalten werden.

Synonymous rare codons are considered to be sub-optimal for gene expression because they are translated more slowly than common codons. Yet surprisingly, many protein coding sequences include large clusters of synonymous rare codons. Rare codons at the 5’ terminus of coding sequences have been shown to increase translational efficiency. Although a general functional role for synonymous rare codons farther within coding sequences has not yet been established, several recent reports have identified rare-to-common synonymous codon substitutions that impair folding of the encoded protein. Here we test the hypothesis that although the usage frequencies of synonymous codons change from organism to organism, codon rarity will be conserved at specific positions in a set of homologous coding sequences, for example to tune translation rate without altering a protein sequence. Such conservation of rarity–rather than specific codon identity–could coordinate co-translational folding of the encoded protein. We demonstrate that many rare codon cluster positions are indeed conserved within homologous coding sequences across diverse eukaryotic, bacterial, and archaeal species, suggesting they result from positive selection and have a functional role. Most conserved rare codon clusters occur within rather than between conserved protein domains, challenging the view that their primary function is to facilitate co-translational folding after synthesis of an autonomous structural unit. Instead, many conserved rare codon clusters separate smaller protein structural motifs within structural domains. These smaller motifs typically fold faster than an entire domain, on a time scale more consistent with translation rate modulation by synonymous codon usage. While proteins with conserved rare codon clusters are structurally and functionally diverse, they are enriched in functions associated with organism growth and development, suggesting an important role for synonymous codon usage in organism physiology. The identification of conserved rare codon clusters advances our understanding of distinct, functional roles for otherwise synonymous codons and enables experimental testing of the impact of synonymous codon usage on the production of functional proteins., Author summary Proteins are long linear polymers that must fold into complex three-dimensional shapes in order to carry out their cellular functions. Every protein is synthesized by the ribosome, which decodes each trinucleotide codon in an mRNA coding sequence in order to select the amino acid residue that will occupy each position in the protein sequence. Most amino acids can be encoded by more than one codon, but these synonymous codons are not used with equal frequency. Rare codons are associated with generally slower rates for protein synthesis, and for this reason have traditionally been considered mildly deleterious for efficient protein production. However, because synonymous codon substitutions do not change the sequence of the encoded protein, the majority view is that they merely reflect genomic ‘background noise’. To the contrary, here we show that the positions of many synonymous rare codons are conserved in mRNA sequences that encode structurally similar proteins from a diverse range of organisms. These results suggest that rare codons have a functional role related to the production of functional proteins, potentially to regulate the rate of protein synthesis and the earliest steps of protein folding, while synthesis is still underway.

Summary To construct gene co-expression networks based on single-cell RNA-Sequencing data, we present an algorithm called LEAP, which utilizes the estimated pseudotime of the cells to find gene co-expression that involves time delay. Availability and Implementation R package LEAP available on CRAN Supplementary information Supplementary data are available at Bioinformatics online.

We examined if the work-related treatment dose has changed in 2014 than compared to 2012, if the work-related treatment dose differed between common medical rehabilitation (MR) and work-related medical rehabilitation (WMR), and if the therapy recommendations for WMR were met in Northern Germany rehabilitation centres in 2014.Patients who were treated in WMR or conventional medical rehabilitation in 2014 were matched with patients treated in 2012 by using propensity scores.Patients who were treated in WMR in 2014 received more work-related interventions than comparable patients in 2012 (13.5 vs. 2.5 h) and MR patients in 2014 (13.5 vs. 1.2 h). 30 min of social counselling, 180 min of work-related psychological groups and 360 min of work-related functional capacity training were realised for 93.8, 82 and 41% of the patients participating in WMR in 2014 CONCLUSION: WMR programs in Northern Germany meet the recommendations of the WMR guideline.

Improved methods for determining bathymetric distributions of dominant intertidal plants throughout their estuarine ranges are needed. Eelgrass (Zostera marina) is a seagrass native to estuaries of the northeastern Pacific and many other marine regions of the northern hemisphere. The techniques described here employed large-format aerial photography using false color near-infrared film with digital image classification, and the production of digital bathymetric models of shallow estuaries, such as those occurring in turbid waters of the United States Pacific Northwest. Application of geographic information system procedures to Z. marina classifications and estuarine bathymetries yielded intertidal eelgrass bathymetric distributions based on a very large number of data points. Similar bathymetric patterns were obtained for the three estuaries surveyed, and approximately 90% of the classified Z. marina occurred within the depth range -1.0 m to +1.0 m (mean lower low water). Comparison of these depth distributions with ground surveys of Z. marina lower depth limits indicated that the area of undetected subtidal eelgrass constituted Zostera marina areal distribution in one estuary was distinctly different from those in the other two systems, which illustrated the potential usefulness of this technique in exploring causal factors for such differences in areal distributions of estuarine intertidal vegetation.

Background: There is a lack of clarity concerning the effect of anxiety on the course of cardiac events following myocardial infarction. Some studies have identified anxiety as a risk factor for further cardiac events. However, it is also considered to be a protective factor, as a higher level of anxiety may improve patient compliance and regular medical checkups. Methods: A group of 76 patients with myocardial infarction underwent physical examination and had their anxiety levels assessed within the first week, and 31 months after myocardial infarction. Cardiac events were documented during the follow-up period. We investigated the predictive value for the occurrence of cardiac events of sociodemographic, psychological and physical parameters when evaluated within the first week after myocardial infarction. Compliancy and regularity of medical checkups were registered. Results: Cardiac events occurred in 24 patients during a mean follow-up period of 31 months. The group of anxious patients not only suffered more often from cardiac events, these events also occurred earlier than in nonanxious patients. Age, gender, partner status, level of anxiety and comorbid diabetes at the time of first assessment proved to be discriminatory variables between patients suffering further cardiac incidents and those free of further events. Anxious patients were more likely to continue smoking, whereas less anxious patients were more likely to give up smoking.

A strategy is described for establishing a simple, inexpensive monitoring program for determining approximate levels of petroleum hydrocarbons in ambient water collected near intake structures of circulating seawater systems. The ambient water is obtained from the depth of intake using a submersible pump, which delivers the sample stream to a dockside partitioning chamber that provides instantaneous grab samples for analysis. A common hand-operated fluorometer equipped for measuring the oil content of a fluid was standardized using a locally-obtained No. 2 marine diesel fuel; oil concentrations in water samples were quantified as Marine Diesel Equivalents (MDE) in parts-per-billion. Surveys conducted along the central Oregon coast following the March 1999 beaching of the drifting freighter New Carissa off Alsea Bay were conducted in that bay, and in Yaquina Bay about 20 km to the north. No evidence of oil contamination from the beached ship was found. The highest MDE levels occurred within the estuaries, especially in an anchorage for fishing vessels in Yaquina Bay. Higher levels of MDE also were measured upstream of this anchorage in February 2001, following a highway spill of No. 6 heavy fuel from a tank truck crash. Thus, this technique appears to be useful for monitoring oil levels in ambient water near seawater intake structures, and to provide a rational basis for temporarily closing down the circulating seawater system after a local oil spill.

Inzwischen ist die Bedeutung des psychosozialen Kontextes fur die Prognose der koronaren Herzkrankheit hinreichend belegt. Die psychosoziale Situation des jeweiligen Patienten sollte deshalb auch in die Risikostratifizierung einbezogen werden. Um dies in der klinischen Praxis zu erleichtern und um gegebenenfalls eine erweiterte psychologische Diagnostik zu bahnen, wird ein neu entwickeltes Instrument zur Fremdbeurteilung der psychosozialen Belastung, das LIPS („Lubecker halbstandardisiertes Interview zum Psychosozialen Screening”) vorgestellt. LIPS leistet uber eine Einzelbewertung der Domanen „Soziale Unterstutzung”, „Belastung/Erschopfung”, „Angst” und „Depression” eine validierte Einschatzung der psychosozialen Gesamtbelastung. Das LIPS erfordert keine psychotherapeutische Ausbildung und lasst sich bei einem Zeitaufwand von funf bis zehn Minuten einfach in das arztliche Gesprach integrieren. Vorgestellt wird hier neben dem im Original abgebildeten Bogen seine Validierung an standardisierten Selbstbeurteilungsinstrumenten.

Amphipods (Eohaustorius estuarius) were placed in two-chamber containers with different combinations of three contaminated sediments and a control sediment, and their distribution was determined after 2 or 3 d. Amphipods avoided the sediment with the highest PAH contamination and one of two sediments with moderate PAH concentrations. In the moderately contaminated sediment avoided by amphipods, the (avoidance) response was more sensitive than mortality as a biological indicator of unacceptable sediment contamination (over the 2–3-d exposure). The avoidance response in this case likely represents an early indication of potential mortality from sediment exposure. Population levels of amphipods in moderately to heavily PAH-contaminated sediments may be influenced by a combination of avoidance behavior and toxicity/lethality.

According to the fugacity approach pollutant uptake by an organism is determined by the chemical fugacity differential between the organism and its environment. The Accumulation Factor (AF) is a simple, fugacity-based model which has been shown to be useful for predicting the bioaccumulation potential of hydrophobic neutral organic compounds in sediment dwelling animals. Previously, the constancy of AFs for ten hydrophobic neutral organic compounds were tested by exposing clams (Macoma nasuta) in the laboratory for 28 days to six field-collected sediments varying widely in C{sub S}, TOC, and other chemical and physical characteristics. Sediment and tissue samples from that study were achieved and later analyzed for 11 polychlorinated biphenyl (PCB) congeners. In this paper the authors report mean and maximum AFs (AF{sub max}) for 11 PCB congeners and test the constancy of the AFs across 5 sediments (treatments) by congener and across the 11 congeners by treatment.

Clams (Macoma nasuta) from an unpolluted site in Yaquina Bay, Oregon were exposed in the laboratory for 28 days to 6 field-contaminated sediments (treatments) which varied widely in concentration of 10 organic pollutants. Mean accumulation factors (AF = (concentration in tissue/lipid, %/100)/(concentration in sediment/total organic carbon, %/100] of 8 neutral organic compounds (DDE [p,p'], 2,2',3,5'6-pentachlorobiphenyl, 2,3',4,4',5-pentachlorobiphenyl, Aroclor 1254, pyrene, chrysene, benzo[a]pyrene, benzo [b, (k)]fluoranthene) were homogeneous across treatments. Statistically significant differences were detected between some treatment AFs for DDD [p, p'] and benz[a]anthracene, and between some chemicals within treatments (experimentwise alpha = 0.05). Accumulation factors were less than 2 and less variable in highly polluted, organically enriched sediments (total organic carbon greater than or equal to 3.69 +/- 0.044%), but sometimes exceeded 2 in clams exposed to surficial (0-2 cm deep) sediments with low pollutant concentration and low organic carbon content (less than or equal to 0.86 +/- 0.037%). These results suggest that the AF model may provide reasonable estimates of bioaccumulation potential of hydrophobic neutral organic compounds in organically enriched, polluted sediments.

The ventilation rates of interstitial and overlying water for the deposit-feeding, tellinid clam Macoma nasuta (Conrad) were determined using two water-soluble dyes to differentiate between the two water sources. A unique exposure chamber, the clambox, was used to separate the inhalant and exhalant siphons of the clam, allowing measurements of dye fluxes and total water ventilated. The results suggested that interstitial water constituted very little (4%) of the total amount of water ventilated by this clam. Factors that could affect the importance of interstitial water as a pollutant uptake route and how these might vary among pollutants or infaunal species are discussed.

The definition and implementation of inter-department and inter-enterprise value chains requires the integration of staff and organisational units as well as the technological integration of involved IT systems. While for simple document-based standard processes suitable solutions already exist, a continuous methodology to model cooperative inter-organisational business processes and their transformation to adequate IT architectures is still missing. Objective of this paper is to develop a modeling methodology for selected classes of typical cooperation problems. Considering a cooperative service scenario as example, this methodology is described in detail and evaluated.

There is overwhelming convincing evidence linking psychosocial factors to outcome of patients with coronary heart disease. Thus, assessment of psychosocial variables should be an integrated part of risk stratification. To facilitate psychosocial assessment in clinical practice and to identify a subset of patients possibly benefitting from extended psychological measures, a new semistandardized interview instrument is presented, called LIPS ("Lübecker halbstandardisiertes Interview zum Psychosozialen Screening"). Beside the well-known and relevant domains social support, emotional stress/vital exhaustion, anxiety and depression, a score for the global psychosocial impairment can be documented. LIPS requires no specialized psychological training, its time requirement is five to ten minutes and it is easily integrated into routine physical and psychosocial assessment. The presentation includes the original instrument in addition to its validation on standardized self-administered questionnaires.

Jeder Leser dieses Buches wird am eigenen Leib und am Beispiel seiner Patientinnen und Patienten schon Erfahrungen mit dem engen Wechselspiel zwischen korperlicher und seelischer Befindlichkeit gemacht haben; etwa, dass Menschen, die hohen Belastungen im Alltagsleben ausgesetzt sind, anfalliger sind fur korperliche Erkrankungen. So gehen etwa die Halfte der Patienten bzw. Patientinnen mit einer koronaren Herzkrankheit (KHK) davon aus, dass Stress eine Hauptursache ihrer Erkrankung ist. Und tatsachlich konnte der Einfluss von psychosozialen Faktoren wie Angst, Depression, hoher subjektiver Belastung oder schlechter sozialer Unterstutzung auf den somatischen Verlauf der KHK inzwischen durch eine Vielzahl von Studien gut belegt werden. Davon handelt der erste Teil dieses Kapitels.

This review describes and summarizes data on the structure and properties of water under normal conditions, at high salt concentration and under high pressure. We correlate the observed conformational changes in nucleic acids with changes in water structure and activity, and suggest a mechanism of conformational transitions of nucleic acids which accounts for changes in the water structure. From the biophysical, biochemical and crystallographic data we conclude that the Z-DNA form can be induced only at low water activity produced by high salt concentrations or high pressure, and accompanied by the stabilizing conjugative effect of the cytidine O4' electrons of the CG base pairs.

SUMMARY Previous studies have demonstrated that an alteration of the interaction between the immune system and the autonomic nervous system may contribute to the pathogenesis of inflammatory arthritides. To address this issue further in patients with rheumatoid arthritis (RA), this study aimed at determining the modulation of b-adrenergic receptors (b2R) on lymphocyte subsets and its impact on cell reactivity. b2R were determined on CD4 + and CD8 + peripheral blood lymphocytes (PBL) and synovial fluid lymphocytes (SFL) from RA patients and normal donors. In parallel, the influence of catecholamines on OKT3-induced T-cell activation was studied. In patients with RA, b2R on SFL were significantly decreased compared to b2R on PBL. Furthermore, a disease activity-correlated significant decrease of b2R on CD8 + PBL was observed. This decrease of b2R was paralleled by a reduced suppressive eAect of catecholamines on OKT3-induced lymphocyte proliferation. Our data give further evidence for an impaired sympathetic influence on the immune response in RA. SINCE the observation that lymphocytes, monocytes/ macrophages and granulocytes possess receptors for catecholamines, mainly of the b2 subclass, an abundance of evidence has accumulated demonstrating that immune reactions are at least in part under control of the sympathetic nervous system [1,2]. Neurotransmitters and neurohormones influence the reactivity of the cells of the immune system, and cytokines interact with central neurones and modulate their activity [3]. The sympathetic nervous system and the immune system are anatomically linked by a dense innervation of the lymphatic tissues such as spleen, thymus and lymph nodes. In these tissues, lymphocytes and sympathetic nerve endings form contacts at a distance that is even shorter than that in synapses [4]. The aetiology of rheumatoid arthritis (RA) remains unknown and its pathogenesis is only incompletely understood. The important role of the nervous system in the pathogenesis of RA was first observed in patients who had additional upper motor neurone hemiplegia or poliomyelitis. In these patients, paralysed joints were spared from the inflammatory process [5]. Investigations on experimental arthritis and experimental allergic encephalomyelitis animal models suggested an influence of the sympathetic nervous system on the immune response in these immunologically mediated disorders [6]. Previous investigations from our group in patients with RA have demonstrated a decreased number of b2-adrenergic receptors (b2R) on peripheral blood mononuclear cells (PBMC) that correlated with the disease activity in these patients [7]. Therefore, the influence of the autonomic nervous system (ANS) may contribute to the alteration of the immune response in RA. To gain more insight into the pathophysiological role of the ANS in RA, we studied the b2R characteristics on CD4 + and CD8 + peripheral blood lymphocytes (PBL) and on synovial fluid lymphocytes (SFL), respectively. Results were correlated with plasma catecholamine levels, the total activity index of RA, and compared to the data determined in healthy donors (HD). In addition, in vitro experiments were performed to evaluate the impact of disease-related b2R modulation on lymphocyte function.

The compilation of 5S rRNA and 5S rRNA gene nucleotide sequences as of 30 September 1996, contains a total of 1661 primary structures of 5S rRNAs or their genes, which is an increase of 928 new sequence entries over the last compilation. It covers sequences from 54 archaea, 449 eubacteria, 34 plastids, nine mitochondria and 430 eukaryotes. The databank uses the format of the EMBL Nucleotide Sequence Data Library complemented by a Sequence Alignment (SA) field including secondary structure information. The taxonomic classification of organisms was totally updated. Now the database is also available via anonymous FTP or WWW.

The paper describes a distributed data acquisition-, control and monitoring system designed and being used for testing large superconducting prototype coils in the upgraded TOSKA facility needed for magnetic confinement in fusion. The system will be used in 1996 for testing the inforced EURATOM LCT coil at 1.8 K, later in a combination with the W7-X demo coil and finally the ITER TF model coil. The system was designed for monitoring and archiving long time operation of the cryogenic facility over several month as well as single shots in experimental operation. To control the cryogenic facility a number of programmable logic controllers mainly SIMATIC-135U were used as front ends. To keep the system flexible, all parameters and configuration data which describe hardware and software set-ups are kept in a database which is maintained by the operating team using ORACLE FORMS [ 1 ] applications on PCs. Periodically sampled and transient recorded data are archived in an ORACLE database residing on an DEC ALPHA Station 250–4/266 starting with an initial storage capacity of 60 GB.

HgCdTe epitaxial layers were grown on (111)B CdTe substrates in a commercially purchased and modified vertical MOCVD reactor. DIPTe, DMCd and elemental Hg were used as reactants and growth takes place at 360°C. Run-to-run reproducibility of composition and electrical properties was studied over a hundred growth runs. Hall measurements show that n-type material is consistently obtained with carrier concentrations in the mid 10'4/cm3 and mobilities as high as good bulk material. LWIR photoconductive devices were fabricated with this low carrier concentration material and tested. The responsivity and the lifetime measurements indicated that these devices perform as well as those fabricated with purchased LPE material. Excellent device performance was obtained on 80-element photodiode arrays fabricated with x''0.3 p-type HgCdTe samples by formin9 flf/p junctions by ion implantation. R0A values obtained are ..1x1Ob Q-cm2 at 77K for Xco 5.7 1m and are highly uniform within an 80-element array. We also report on an all MOCVD grown p-on-n double-layer heterojunction (DLHJ) photodiode with Xco 8.1 um.

1. The depuration rate constant for [ 14 C]hexachlorobenzene (HCB) in the clam, Macoma nasuta, was determined following a short-term exposure to HCB contaminated seawater. 2. Depuration was not correlated with ventilation volume, nor did the amount of sediment ingested during depuration have a significant effect. 3. The half-life for HCB in M. nasuta was estimated to be 16 days with a bioconcentration factor of 3490 (wet weight basis).

“Green tides” or blooms of ulvoid green algae are frequent in Yaquina Bay estuary on the central Oregon coast, USA. Measurements of their biomass were made from late spring to early winter in 1999 at six intertidal sites in the estuary, and were continued through the winter of 2002 at two sites that showed the greatest accumulation. The dominant blooming species were the Enteromorpha linza complex, Ulva fenestrata, E. flexuosa, and E. intestinalis. Red and brown algal abundance was negligable. Nutrients in the central channel were monitored, along with incident light and water column absorbence, and sediment temperature. The abundance of benthic amphipods was negatively correlated with the concentration of dissolved sulfides in porewater. However, dissolved sulfide levels were not correlated with green macroalgae biomass. Additional correlations were sought between the variables measured in an effort to suggest or negate major cause and effect relationships. This research is relevant to discerning the effects of eutrophication as a stressor on estuarine processes and could contribute toward an understanding of anthropogenic impacts on biological communities in coastal ecosystems.

Contaminated sediment exposure experiments were conducted using a marine deposit-feeding clam (Macoma nasuta) to determine biota-sediment accumulation factors (BSAFs) based on ingested sediment and fecal organic carbon. Internal, or gut, BSAFs were determined for hexachlorobenzene and 13 polychlorinated biphenyl congeners and were compared to those found with the standard method of calculating BSAFs, which uses the organic carbon and contaminant concentration of the whole or external sediment. The results of these experiments indicated that gut BSAFs were consistently smaller and less variable across sediment types than the corresponding standard BSAFs. Although these results indicate that using ingested sediment concentrations and fecal total organic carbon to calculate gut BSAFs might improve the predictive ability of the standard BSAF model, the benefit is small when compared to the difficulty in measuring the contaminant concentration on ingested sediment and the organic carbon content of feces.

A model is proposed for the determination of orientational relaxation parameters by fluorescence correlation spectroscopy. Specific autocorrelation functions G(τ) are tabulated for different experimental arrangements.

The longitudinal distribution of dissolved silicon in the Yaquina Estuary is described in surface and bottom waters. Non-conservative behaviour is a function of high insolation and low runoff; residence time is the primary controlling factor.

The electron ionization coefficients for Ar, Kr, and Xe have been measured in the low E/N region [(0.5–4) ×10−16 V cm2] using a drift‐tube apparatus. At low field values, the ionization coefficient was found to be anomalously large, a fact attributed to surface photoelectron emission from radiating metastables. This contribution also explains the discrepancy between earlier measurements and recent calculations based on the transport equation. The measurements were analyzed on the basis of two contributions to the ionization rate and calculations of the transport equation, yielding a revised set of inelastic cross sections which differ from earlier ones primarily in the inclusion of shape resonances.

The near infrared laser emission from Xe in Ar and He mixtures has been investigated experimentally in an ionizer‐sustainer mode, and theoretically. An efficiency of 1.3% has been achieved from Ar : Xe, 150 : 1, at 1900 Torr with aproximately 75% of the output contained in a single line at 1.73 μm. Based on a detailed kinetic study of the discharge, the laser behavior is attributed to a two‐stage excitation in which a large excited‐state population is created during the first portion of the discharge followed by excitation and ionization of these excited states and strong lasing during the remaining low‐field portion. The processes leading to the strong emission include electron‐impact excitation from low‐lying excited states, dissociative recombination pumping, and cascade pumping from higher‐lying levels, all of which means that the original excitation energy is being recirculated. The desired high Ar pressure is explained on the basis of providing an impedance match to the sustainer circuit and because the elastic (momentum) losses, at low fields, are nominal allowing a small excited‐state density to dominate the fractional‐loss spectra.

This paper describes the design and implementation of a versatile and compact signal averager interface between a Biomation 6500 transient recorder and an LSI‐11 microcomputer. The design allows for fast signal averaging in excess of 1 kHz and is also easily software configurable and controllable. This permits the rapid recovery of high‐speed waveforms at a minimum sampling time of 2 ns (500 MHz sampling rate). The interface has been incorporated into an LSI‐11 system using the RT‐11 V3B operating system and found to perform very satisfactorily.

Relative cross sections for the following reactions are reported: in which X2 is (a) H2, (b) D2, and (c) HD. The isotope effect in the production of HeH+ and HeD+ in Reaction (2c) was determined and relative measurements were made of the kinetic energy of the ion product in Reaction (1). The cross section for the secondary reaction was also determined as a function of the relative kinetic energy of the reactants. This energy‐dependent cross section was determined for H2+ formed both by helium metastable atom collisions and by electron impact. The cross section for H+2 formed by metastable helium was found to be greater than for H+2 formed by electron impact. This may be evidence for an additional reaction producing H+3 involving highly excited Rydberg states of H2 as reactants.

An exposure chamber, the “clambox”, was developed to measure ventilation rate, sediment processing rate, and efficiency of pollutant uptake by Macoma nasuta conrad, a surface deposit-feeding clam. Clams, collected from Yaquina Bay, Oregon, USA, were cemented into a hole in a piece of rubber dental dam so that the inhalant and exhalant siphons were separated by a membrane. The dental dam was then clamped between two glass chambers. The inhalant and exhalant siphons were thus directed into separate chambers of the device so that the amounts of water or feces discharged into the exhalant chamber provided direct measures of ventilation rate and sediment processing rate, respectively. Clams exhibited no stress from the procedure. Ventilation rate was not affected by the imposition of a 5 mm hydraulic head in the exhalant chamber, by having sediment only in the inhalant chamber, or by exposure to organic-free sediment. The mean weight-specific ventilation rate for M. nasuta was 7.3 ml g-1 h-1 on a wet-flesh basis. This low rate, compared to rates for filter-feeding bivalves, supports the contention that deposit-feeding is the dominant feeding mode for M. nasuta. The short-term pattern was for ventilation to be intermittenly interrupted, essentially ceasing for 12 to 120 min, followed by a short period of active ventilation and then a resumption of the normal rate. Less than 3% of the total water flux could be attributed to water which entered the body cavity across the mantle margin. Water exhaled from the inhalant siphon during the ejection of pseudofeces was

Photoconductive detector arrays fabricated from metalorganic chemical vapor deposited epitaxial films of Hg0.8Cd0.2Te on both CdTe and Al2O3 substrates are reported for the first time. These devices operate in the 8–12‐μm spectral region and have detectivities of 3.6×1010 and 2.6×1010 cm Hz1/2/W for CdTe and Al2O3 substrates, respectively. These results approach background limited performance, and as such establish the feasibility of metalorganic chemical vapor deposited HgCdTe for use in advanced infrared detection systems.

The longitudinal distribution of total suspended matter and total, dissolved, and particulate manganese in a small coastal plain estuary is described. The distribution of manganese is a consequence of estuarine circulation; a within-estuary maximum is inversely correlated with river flow, and is a function of residence time in the estuary, resuspension in the upper estuary, and desorption from particles introduced from within the estuary or from the river. The turbidity maximum is similarly most pronounced during low river flows. The upper estuary (salinity