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ABSTRACTFollowing is the text of a letter, dated December 23, 1953, from Major General K. D. Nichols, general manager of the Atomic Energy Commission, to Dr. J. Robert Oppenheimer.

Core IdeasInformation about forage‐induced changes to soil properties is lacking.Soil responses to perennial forages were quantified in a semiarid region over 5 yr.Perennial forages maintained or improved near‐surface soil conditions.However, effects were subtle and changes to soil properties occurred slowly. Integration of perennial forages in annual cropping systems can expand ecosystem service benefits to agricultural landscapes. Such benefits are frequently derived from changes to soil properties. Unfortunately, there is limited guidance for agricultural producers regarding the length of time needed to accrue soil condition improvements under perennial forages, particularly for semiarid regions. The objective of this study was to quantify soil responses to perennial grasses, legumes, and grass–legume mixtures over a 5‐yr year period in a semiarid region. Select soil physical and chemical properties were measured within five perennial forage treatments and under annual cropping over a 5‐yr period on a Parshall fine sandy loam near Mandan, ND. Treatment effects on soil properties were limited to the surface 10 cm. Differences in soil properties between spring wheat (Triticum aestivumL.) and perennial forages were most frequent following the fourth stand year. Compared with spring wheat, perennial forages mitigated soil acidification (by 0.26–0.65 pH units), reduced soil bulk density (by 0.04–0.08 Mg m–3), and increased particulate organic matter (POM) (by 0.41 g C kg–1) and water‐stable aggregates (by 3.8%). Among perennial forages, intermediate wheatgrass (Thinopyrum intermediumL.) and intermediate wheatgrass–field pea (Pisum sativumL) mixture followed by alfalfa (Medicagospp.) reduced soil bulk density (by 0.06–0.11 Mg m–3) and increased POM (by 0.24–0.92 g C kg–1) compared with alfalfa following 4‐ and 5‐yr perennial forage stands. While these outcomes suggest perennial forages can improve the near‐surface soil condition, accrual of improvements may be slow and subtle in semiarid regions.

Cognitive problems are a significant, persistent concern for patients undergoing hematopoietic stem cell transplant (HSCT). Sleep is important for many cognitive tasks; however, the relationship between sleep and cognitive problems for HSCT patients is unknown. This study examined the relationship between sleep and cognitive problems for HSCT patients from pre to post transplant. Patients undergoing HSCT (N=138) completed questionnaires at pre-transplant and during the 12 months following transplant. Questionnaires assessed sleep and cognitive problems as well as commonly co-occurring symptoms: depressive symptoms, fatigue and pain. Post hocanalyses examined the relationship of specific sleep problems with cognitive problems. Sleep problems covaried with cognitive problems even after controlling for depressive symptoms, fatigue and pain. Depressive symptoms and fatigue were also uniquely related to cognitive problems. Post hocanalyses suggest that sleep somnolence, shortness of breath, snoring and perceptions of inadequate sleep may contribute to the association found between sleep and cognitive problems. Findings suggest that sleep problems are associated with and may contribute to cognitive problems for HSCT patients. However, sleep problems are rarely screened for or discussed during clinic visits. Assessing and treating specific sleep problems in addition to depressive symptoms and fatigue may have implications for improving cognitive problems for HSCT patients.

Invariant natural killer T cells (iNKTs) are innate-like lipid-reactive T lymphocytes that express an invariant T-cell receptor (TCR). Following engagement of the iTCR, iNKTs rapidly secrete copious amounts of Th1 and Th2 cytokines and promote the functions of several immune cells including NK, T, B and dendritic cells. Accordingly, iNKTs bridge the innate and adaptive immune responses and modulate susceptibility to autoimmunity, infection, allergy and cancer. Allogeneic hematopoietic stem cell transplantation (HSCT) is one of the most effective treatments for patients with hematologic malignancies. However, the beneficial graft versus leukemia (GvL) effect mediated by the conventional T cells contained within the allograft is often hampered by the concurrent occurrence of graft versus host disease (GvHD). Thus, developing strategies that can dissociate GvHD from GvL remain clinically challenging. Several preclinical and clinical studies demonstrate that iNKTs significantly attenuate GvHD without abrogating the GvL effect. Besides preserving the GvL activity of the donor graft, iNKTs themselves exert antitumor immune responses via direct and indirect mechanisms. Herein, we review the various mechanisms by which iNKTs provide antitumor immunity and discuss their roles in GvHD suppression. We also highlight the opportunities and obstacles in manipulating iNKTs for use in the cellular therapy of hematologic malignancies.

Uropathogenic Escherichia coli (UPEC) is the main etiological agent of urinary tract infections (UTIs). Little is known about interactions between UPEC and the inflammasome, a key innate immune pathway. Here we show that UPEC strains CFT073 and UTI89 trigger inflammasome activation and lytic cell death in human macrophages. Several other UPEC strains, including two multidrug-resistant ST131 isolates, did not kill macrophages. In mouse macrophages, UTI89 triggered cell death only at a high multiplicity of infection, and CFT073-mediated inflammasome responses were completely NLRP3-dependent. Surprisingly, CFT073- and UTI89-mediated responses only partially depended on NLRP3 in human macrophages. In these cells, NLRP3 was required for interleukin-1β (IL-1β) maturation, but contributed only marginally to cell death. Similarly, caspase-1 inhibition did not block cell death in human macrophages. In keeping with such differences, the pore-forming toxin α-hemolysin mediated a substantial proportion of CFT073-triggered IL-1β secretion in mouse but not human macrophages. There was also a more substantial α-hemolysin-independent cell death response in human vs. mouse macrophages. Thus, in mouse macrophages, CFT073-triggered inflammasome responses are completely NLRP3-dependent, and largely α-hemolysin-dependent. In contrast, UPEC activates an NLRP3-independent cell death pathway and an α-hemolysin-independent IL-1β secretion pathway in human macrophages. This has important implications for understanding UTI in humans.

Uropathogenic Escherichia coli(UPEC) is the main etiological agent of urinary tract infections (UTIs). Little is known about interactions between UPEC and the inflammasome, a key innate immune pathway. Here we show that UPEC strains CFT073 and UTI89 trigger inflammasome activation and lytic cell death in human macrophages. Several other UPEC strains, including two multidrug-resistant ST131 isolates, did not kill macrophages. In mouse macrophages, UTI89 triggered cell death only at a high multiplicity of infection, and CFT073-mediated inflammasome responses were completely NLRP3-dependent. Surprisingly, CFT073- and UTI89-mediated responses only partially depended on NLRP3 in human macrophages. In these cells, NLRP3 was required for interleukin-1β (IL-1β) maturation, but contributed only marginally to cell death. Similarly, caspase-1 inhibition did not block cell death in human macrophages. In keeping with such differences, the pore-forming toxin α-hemolysin mediated a substantial proportion of CFT073-triggered IL-1β secretion in mouse but not human macrophages. There was also a more substantial α-hemolysin-independent cell death response in human vs. mouse macrophages. Thus, in mouse macrophages, CFT073-triggered inflammasome responses are completely NLRP3-dependent, and largely α-hemolysin-dependent. In contrast, UPEC activates an NLRP3-independent cell death pathway and an α-hemolysin-independent IL-1β secretion pathway in human macrophages. This has important implications for understanding UTI in humans.

Cover crops can expand ecosystem services, though sound management recommendations for their use within semiarid cropping systems is currently constrained by a lack of information. This study was conducted to determine agroecosystem responses to late‐summer seeded cover crops under no‐till management, with particular emphasis on soil attributes. Short‐term effects of late‐summer seeded cover crops on soil water, available N, near‐surface soil quality, and residue cover were investigated during three consecutive years on the Area IV Soil Conservation Districts Research Farm near Mandan, ND. Mean aboveground cover crop biomass was highly variable across years (1430, 96, and 937 kg ha−1in 2008, 2009, and 2010, respectively), and was strongly affected by precipitation received within 14 d following cover crop seeding. During years with appreciable biomass production (2008 and 2010), cover crops significantly reduced available N in the 0.9‐m depth the following spring (P= 0.0291 and 0.0464, respectively). Cover crop effects on soil water were subtle, and no differences in soil water were found between cover crop treatments and a no cover crop control before seeding cash crops the following spring. Late‐summer seeded cover crops did not affect near‐surface soil properties or soil coverage by residue. Soil responses to late‐summer seeded cover crops did not differ between cover crop mixtures and monocultures. Late‐summer seeded cover crops may enhance ecosystem services provided by semiarid cropping systems through biomass production and N conservation, though achieving these benefits in a consistent manner appears dependent on timely precipitation following cover crop seeding.

To develop appropriate bioenergy production systems to match site‐specific situations, establishment and yield were evaluated for switchgrass (Panicum virgatumL.), intermediate wheatgrass [Thinopyrum intermedium(Host) Barkworth and D.R. Dewey], tall wheatgrass [Thinopyrum ponticum(Podp.) Z.‐W. Liu and R.‐C. Wang], and three binary mixtures at four sites in North Dakota from 2006 to 2011. One year after seeding in 2007, intermediate wheatgrass, tall wheatgrass, a binary mixture of tall wheatgrass and intermediate wheatgrass, and a binary mixture of tall wheatgrass with ‘Sunburst’ switchgrass (dominated by tall wheatgrass) stand canopy cover was above 85% at all four sites. Sunburst switchgrass and its binary mixture with big bluestem (Andropogon gerardiiVitman) stand canopy cover reached 100% at Carrington, the most eastern site; and below 35% at Williston, the most western site, 1 yr after seeding. Meanwhile, their stand canopy cover was more than 70% at Minot and Streeter, the north central and south central sites, respectively, 2 to 3 yr after seeding. Sunburst switchgrass produced the highest biomass at Carrington (10.6 ± 1.8 Mg ha−1), whereas intermediate wheatgrass was the highest at Williston (3.0 ± 1.0 Mg ha−1). The binary mixture of tall wheatgrass with Sunburst switchgrass had the highest yield at Minot (8.5 ± 2.5 Mg ha−1) and Streeter (6.7 ± 1.9 Mg ha−1). Yields of binary mixtures were at least comparable to and sometimes higher than those of their compositional component monocultures. Binary mixtures with carefully selected species could have potential for bioenergy production systems in North Dakota.

Soil quality, soil health, and soil sustainability are concepts that are being widely used but are difficult to define and illustrate, especially to a non-technical audience. The objectives of this manuscript were to develop simple and inexpensive methodologies to both qualitatively and quantitatively estimate water infiltration rates (IR), water-holding capacity at saturation (WHCs), and potential nitrate-nitrogen (NO3–N) loss and to test the accuracy and precision of these methods. Complete details for how to assemble the appropriate supplies and conduct the measurements are provided, but for demonstrative purposes these methods do not need to be followed in detail, particularly using the various equations to get quantitative values. In the field and classroom, these demonstrations have been well received by non-technical and technical audiences and have been performed by request as well as incorporated into agronomy classes for high school and college students and training for agriculture educators. In the laboratory, these methods were tested on 10 benchmark soils and values were compared with each other and soil aggregation as measured by dry soil aggregate distribution and water stability. In these benchmark soils, IR and WHCsincreased with a reduction in soil disturbance and more continuous plant cover due to diverse crop rotation and perennials while NO3–N loss was highest in soils with synthetic fertilizer inputs, little plant cover, and more soil disturbance. These results indicate the methodologies outlined here may be used to demonstrate agroecosystem management's impact on soil health.

Infectious Ceratomyxa shastaand Parvicapsula minibicornisactinospores were present in Klamath River samples collected in April, May, and June 2005. Juvenile Chinook salmon Oncorhynchus tshawytschaexposed to river water maintained at the ambient Klamath River temperature for 0, 4, 24, 72, and 168 h (7 d) developed asymptomatic infections from both parasites. Elevated water temperature (18°C) in June may have reduced actinospore viability, as both C. shastaand P. minibicornisinfection markedly declined in fish exposed for over 72 h. As judged by the prevalence of infection for both parasites, the number of infectious actinospores tended to increase or remain steady through the spring. Ceratomyxa shastainfections were characterized by the presence of a few trophozoites within granulomatous foci in mesentery adipose tissue and were consistently observed outside of the intestine. Similarly, low numbers of P. minibicorniswere observed in kidney glomeruli and tubules but were not associated with inflammation. Parvicapsula minibicornisDNA was consistently detected by quantitative real-time polymerase chain reaction in filtered water samples collected each month and from each time posttransfer. These data and the high prevalence of infection observed in the exposed fish indicate that P. minibicornisactinospores were at a relatively high concentration in the river during the spring. In contrast, C. shastaDNA was only detected in half of the water sample sets and its detection did not correspond well to C. shastainfectivity. An approximately threefold increase in river flow from the April to the May water collection was not associated with a decline in either the detection of actinospores (particularly for P. minibicornis) or the prevalence of infection for both parasites. Actinospores of these myxosporean parasites have the potential to infect salmonids for at least 7 d after release from the alternate polychaete host.

AbstractInfectious Ceratomyxa shastaand Parvicapsula minibicornisactinospores were present in Klamath River samples collected in April, May, and June 2005. Juvenile Chinook salmon Oncorhynchus tshawytschaexposed to river water maintained at the ambient Klamath River temperature for 0, 4, 24, 72, and 168 h (7 d) developed asymptomatic infections from both parasites. Elevated water temperature (18°C) in June may have reduced actinospore viability, as both C. shastaand P. minibicornisinfection markedly declined in fish exposed for over 72 h. As judged by the prevalence of infection for both parasites, the number of infectious actinospores tended to increase or remain steady through the spring. Ceratomyxa shastainfections were characterized by the presence of a few trophozoites within granulomatous foci in mesentery adipose tissue and were consistently observed outside of the intestine. Similarly, low numbers of P. minibicorniswere observed in kidney glomeruli and tubules but were not associated with inflammation. Parvicapsula minibicornisDNA was consistently detected by quantitative real-time polymerase chain reaction in filtered water samples collected each month and from each time posttransfer. These data and the high prevalence of infection observed in the exposed fish indicate that P. minibicornisactinospores were at a relatively high concentration in the river during the spring. In contrast, C. shastaDNA was only detected in half of the water sample sets and its detection did not correspond well to C. shastainfectivity. An approximately threefold increase in river flow from the April to the May water collection was not associated with a decline in either the detection of actinospores (particularly for P. minibicornis) or the prevalence of infection for both parasites. Actinospores of these myxosporean parasites have the potential to infect salmonids for at least 7 d after release from the alternate polychaete host.

Abstract: Humic substances [humic acid (HA), fulvic acid (FA), and insoluble humin], particulate organic matter (POM), and glomalin comprise the majority (ca 75%) of operationally defined extractable soil organic matter (SOM). The purpose of this work was to compare amounts of carbon (C) and nitrogen (N) in HA, FA, POM, and glomalin pools in six undisturbed soils. POM, glomalin, HA, and FA in POM, and glomalin, HA, and FA in POM-free soil were extracted in the following sequence: (1) POM fraction separation from the soil, (2) glomalin extraction from the POM fraction and POM-free soil, and (3) co-extraction of HA and FA from the POM fraction and POM-free soil. Only trace amounts of HA and FA were present in the POM fraction, while POM-associated glomalin (POM-glomalin) and POM alone contributed 2 and 12%, respectively, of the total C in the soil. Mean combined weights for chemically extracted pools from POM and from POM-free soil were 9.92 g glomalin, 1.12 g HA, and 0.88 g FA kg−1 soil. Total protein and C, N, and H concentrations showed that glomalin and HA were, for the most part, separate pools, although protein was detected in HA extracts. Even though percentage carbon was higher in HA than in glomalin, glomalin was a larger (almost nine times) operationally defined pool of soil organic C. Glomalin was also the largest pool of soil N of all the pools isolated, but all pools combined only contained 31% of the total N in the soil.

Two important extractable fractions of soil organic matter (SOM) arehumic acid (HA) and glomalin-related soil protein (glomalin). Optimizing the purity of each fraction is necessary to correlate fraction quantity and molecular characteristics with soil quality. Manipulation of extraction sequence and controlled precipitation of HA were used to evaluate co-extraction of HA and glomalin. Eight bulk soil samples (0 to 10 cm depth) were collected from four U.S. states (Colorado, Nebraska, Maryland, and Georgia). In Experiment 1, glomalin extraction (50 mM citrate, pH 8.0, at 121 °C) was followed by HA extraction (0.1 NNaOH at room temperature), and Experiment 2 used the reciprocal sequence. Experiment 2 HA was precipitated stepwise at pH levels 2.5, 2.0, and 1.0. Gravimetric weight, Bradford-reactive soil protein (BRSP), and immunoreactive soil protein (IRSP), along with percentages of C, N, H, and Fe, were used to compare glomalin and HA. The HA fraction from Experiment 2 contained 2-fold greater amounts of BRSP than HA from Experiment 1 and showed that pre-extraction of glomalin improved the purity of HA. The glomalin fraction from Experiment 1 contained 1.5 times the BRSP of glomalin from Experiment 2 and was twice the gravimetric weight. BRSP and gravimetric weight were concentrated in HA that precipitated at pH 2.5 or 2.0 and percentage IRSP was significantly higher in the pH 2.5 precipitate. The results indicate that glomalin should be extracted first and examined as a biomolecule separate from the humic acid mixture. Percentages C, H, N, and Fe in glomalin varied across soils and experiments. In seven soils, the changes inFe percentage in glomalin from Experiment 1 to 2 were significantly correlated with the changes in glomalin weight and %C. Iron in glomalin from Experiment 1 was related to soil pH and clay content, whereas soil organic C was positively and significantly correlated with Experiment 1 glomalin BRSP and IRSP. In Experiment 1, a recalcitrant pool of glomalin was released by treating soil with NaOH, suggesting that a fraction of glomalin is difficult to remove from soil and glomalin extraction efficiency could be improved. Refinements to extraction and purification protocols such as pretreatment of soils with HCl and sequential extraction can facilitate studies on organic matter structure and function.

Planar gated blood-pool imaging (GBPI) is a standard method for non-invasive assessment of left ventricular (LV) function. Gated blood-pool single photon emission computed tomographic (GBPS) data acquisition can be accomplished in the same time as GBPI, with the benefit of enabling visualization of all cardiac chambers simultaneously. The purpose of this investigation was to evaluate the degree to which automated and manual LVEF calculations agree with one another and with conventional GBPI LVEF measurements. GBPI studies were performed in 22 consecutive, unselected patients, followed by GBPS data acquisition. GBPS left ventricular ejection fraction (LVEF) calculations were performed by available software (NuSMUGA, Northwestern University, Chicago, IL) automatically and manually, using all LV gated short axis slices. Automatic LVEF assessed by GBPS correlated well with conventional planar GBPI (r0.88, P<0.001). Mean planar GBPI LVEF was 50±12, and mean GBPS automatic LVEF was significantly lower at 45±14 (P0.001), with a mean difference of 6±5. Manual GBPS LVEF also correlated well with conventional planar GBPI (r0.90, P<0.0001). Mean LVEF measurement by manual GBPS versus GBPI was significantly higher at 59±13, with a mean difference of 10±6 (P<0.001). Manual GBPS LVEF values were also significantly higher than automatically determined GBPS LVEF values (P<0.001). It is concluded that LVEF values assessed by NuSMUGA GBPS software were reproducible, and automatic and manual values correlated well with conventional GBPI values. However, both automatic and manual GBPS calculations were significantly different from one another and from GBPI values, so that GBPI and NuSMUGA calculations cannot be considered to be equivalent.

Expression of HLA-DR surface antigens by granulocyte/monocyte colony- forming cells (CFU-GM) may be important in the regulation of proliferation of these cells. Using immunological techniques to enrich for progenitor cells, we investigated the expression of HLA-DR in subsets of CFU-GM. “Early” (day 14) CFU-GM express higher levels of HLA- DR than do “late” (day 7) CFU-GM. Among late CFU-GM, cells destined to form monocyte (alpha-naphthyl acetate esterase-positive) colonies express higher levels of HLA-DR than do CFU-GM destined to form granulocyte (chloroacetate esterase-positive) colonies. Because high- level expression of DR antigen was a marker for monocyte differentiation, we examined several lymphokines for their effects on both DR expression and in vitro commitment to monocyte differentiation by myeloid precursor cells. DR antigen density could be increased by more than twofold over 48 hours upon exposure to gamma-interferon (gamma-IFN), whereas colony-stimulating factors had no effect. This was associated with a dose-dependent inhibition of total CFU-GM number, and a relative, but not absolute, increase in the ratio of monocyte colonies to granulocyte colonies. Similarly, in day 7 suspension cultures of purified myeloid precursor cells, gamma-IFN inhibited cell proliferation and increased the ratio of monocytes to granulocytes. Thus, despite the induction of high levels of HLA-DR antigen on precursor cells (a marker of monocyte commitment), the dominant in vitro effect of gamma-IFN was inhibition of granulocyte differentiation.

Laminar preparations of fixed segments of the guinea-pig intestine were examined for nitric oxide synthase activity using reduced nicotinamide adenine dinucleotide phosphate and nitroblue tetrazolium salt as substrates. Under conditions specific for detecting nitric oxide synthase-related diaphorase activity, a subpopulation of neural elements in the myenteric plexus, deep muscular plexus and submucosa were intensely stained. Intensely stained nerve fibres were distributed throughout the meshworks of the myenteric plexus and its innervation of the circular muscle, and in the submucosa within Henle's plexus. Intensely stained nerve cells and their processes were evident in most myenteric ganglia but were rare in ganglia of Henle's plexus. Stained ganglion cells comprised types I, II and VI of the morphologically defined enteric nerve cells. Stained neural elements were increasingly prevalent within successively more caudal segments of the intestine. In addition to neuronal staining, arterioles of the submucosal vascular network displayed distinct, punctate patches of staining distributed over their surface. Perivascular nerve fibre staining was absent.

To determine if metal ions play a contributing role in loosening of orthopedic implants, the present work investigated whether sublethal concentrations of ions affect the formation and function of osteoclasts in vitro. Rat bone marrow cells were cultured on slices of devitalized bone and in the presence of ions associated with Co-Cr-Mo and Ti-6Al-4V alloys for up to four weeks. Cultures were assayed for total intracellular protein, used as measure of cell growth, and resorption activity of osteoclastic cells derived from hematopoietic stem cells was quantified using image analysis. Although Co2+caused delayed toxicity not previously observed during short-term experiments, none of the other ions affected cell proliferation, indicating that the chosen concentrations were sublethal. In general, exposure of bone marrow cultures to ions caused either a decrease or no change in the total area of bone resorption. A decrease in the number of resorption pits formed by osteoclastic cells was primarily responsible for the decrease in total amount of resorption. Therefore, even though cells continued to grow over the entire culture period, less osteoclastic activity was observed. Findings indicate that if metal ions play a role in periprosthetic pathology, they may contribute to implant failure by impairing bone repair while allowing fibrous tissue formation following debris-induced osteolysis. © 1997 John Wiley & Sons, Inc.

This paper describes the SCHOLAR silicon compiler and the use of the Silvar-Lisco design suite, the HILO3 simulator and a cell library, obtained under the ECAD initiative, in a silicon compilation/module generation environment. SCHOLAR is a general silicon compiler for synthesis of concurrent VLSI systems from behavioural-level descriptions.

The flagellar frequency and waveform of Euglena were analyzed under full illumination (420-700 nm) and in a restricted wavelength band (530-700 nm) when the cells were in a medium containing Mg2+ or had been microinjected with Mg2+, Mn2+, or Ca2+ in solution. Magnesium abolished the change in flagellar frequency and the reversal in waveform that cells exhibit when illuminated by a 530-700 nm wavelength band. Under this restricted illumination, Ca2+ caused an increase in flagellar waveform reversal and a decrease in beating frequency. The flagellar motility of cells impaled on a microelectrode was examined in cells illuminated with various wavelengths.

The relationship between the structural quality of low-temperature GaAs layers and the photoexcited carrier lifetime has been studied. Transmission electron microscopy, x-ray rocking curves, time-resolved reflectance methods, and photoconductive-switch-response measurements were used for this study. For a variety of samples grown at temperatures in the vicinity of 200°C, subpicosecond carrier lifetimes were observed both in as-grown layers, as well as in the same layers after post-annealing and formation of As precipitates. These results suggest that the carrier lifetime, which was found to be shorter in the as-grown layers than in the annealed ones, might be related to the density of AsGaantisite defects present in the layers. The annealed layers which contained structural defects before annealing appeared to exhibit the longest carrier lifetime due to gettering of As on these defects (and formation of relatively large As precipitates) and depletion of extra As (AsGa) defects from the layer. It was found as well that the responsivity of detectors fabricated on these layers depended strongly on the structural quality of the layers, with the greatest response obtained not for the layers with the fewest defects, but for the layers with 107–108/cm2of pyramidal defects.

Gallium arsenide electroabsorption avalanche photodiode (EAP) detectors have been fabricated in n − n^+ GaAs waveguides. Since these EAP detectors respond to wavelengths beyond the normal absorption edge of GaAs, due to the Franz-Keldysh effect, they have been used to detect the below band gap radiation from GaAs lasers and the 1.06-μm radiation from Nd:YAG lasers. The measured absorption and responsivity at these wavelengths suggest a number of applications. These EAP devices have been used to detect analog signals with a distortion less than 6%. Methods for utilizing them in time- and frequency-demultiplexing applications are also described.

The factors which influence the size of the heat-affected zone of a material on which a focused electron beam is incident are reviewed. These include the limitation of current density in the focused spot, which is given by the Langmuir relation, and also the limitation imposed by the spherical aberrations of the lens which focuses the beam. The peak temperature rise in the material, with due allowance for the source penetration and backscatter effects, is discussed. The design requirements for electron beam machines are then considered. These are followed by brief descriptions of a number of machines which have been used for the machining of thin films, deposited on substrates, and for the machining of self-supporting thin foils. The principal features of the machined films and foils are described. The review concludes with an account of the various explanations which have been put forward to account for the observed experimental results.

Archived soil samples are an important resource for quantifying changes in soil attributes over decadal time scales. Herein, we describe a soil archive at the USDA‐ARS Northern Great Plains Research Laboratory (NGPRL) near Mandan, ND with the intent of encouraging research collaboration through utilization of the archive. Over 5000 samples are included in the NGPRL soil archive, ranging in age from 4 to 90 yr. Samples were derived from both grazing and cropping studies, with the former being conducted near Mandan, and the latter as a part of an evaluation of soil C and N change at multiple locations throughout the Great Plains. Most samples are associated with soil depths above 30.5 cm, although 10 locations from the Great Plains evaluation possess archived soils below 1 m for native vegetation treatments. Collaborative research opportunities using the NGPRL soil archive abound, and may include characterizations of soil organic matter fractions, micronutrients, and soil acidity. Scientists interested in engaging in collaborative research efforts are encouraged to contact the authors of this report.

Test scores from chronic schizophrenics are presented which add evidence for the concept of overinclusion as a complex set of phenomena which involve different subtypes variously related to one another and variously modified by emotional state.

An algorithm for the transient analysis of nonlinear networks is described. It uses a nodal-admittance representation and an implicit integration technique. The algorithm allows a compact and fast computer implementation, ideally suited to small-computer environments. An example of results obtained with an ALGOL implementation is given.