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Rising atmospheric CO2has stimulated plant productivity, with terrestrial ecosystems currently absorbing nearly one-third of anthropogenic CO2emissions. Increases in photosynthesis can subsequently lead to increased carbon (C) storage in plants and soil. However, there is growing evidence that nitrogen (N) availability constrains elevated CO2(eCO2) responses, yet we know much less about the role of phosphorus (P) limitation on productivity under eCO2. This is important because P-limited ecosystems are globally widespread, and the biogeochemical cycles of N and P differ fundamentally. In the Peak District National Park of northern England, we conducted a free-air CO2enrichment (FACE) experiment for three years on two contrasting P-limited grasslands under long-term nutrient manipulation. Here we show that competition between plants and microbes for P can determine plant productivity responses to eCO2. In a limestone grassland, aboveground productivity increased (16%) and microbial biomass P remained unchanged, whereas in an acidic grassland, aboveground productivity and P uptake declined (11% and 20%, respectively), but P immobilization into microbial biomass increased (36%). Our results demonstrate that strong competition with microbes can cause plant P uptake to decline under eCO2, with implications for the future productivity of P-limited ecosystems in response to climate change.

In this work, a field-applicable, simple method for quick detecting chlorogenic acid (CGA) was developed. The method is based on CGA’s antioxidant property. CGA is reported to reduce a mixture solution of FeCl3/K3Fe(CN)6to generate Fe4[Fe(CN)6]3, the Prussian blue, in an aqueous solution. This reaction was adopted in this work by using solid-ink printed annuli on a filter-paper as reaction vessels. The reagent is pre-loaded and dried within the solid ink printed circles. In a field test, a drop of a sample solution is directly applied to a reagent-loaded circle. The reaction product within the circle shows a blue color, which is detected by using an iPad (or cellphone) camera as a detector and a light-emitting diode flashlight lamp as a light source. A freely available RGB colorimeter program from Apple store was used to read light intensity of three colors: red, green, blue, and absorbance signal of red and blue light is calculated. The difference of absorbance signal of red light from that of blue light was found having linear relationship with CGA concentration in an aqueous sample solution. This simple method is sensitive with a detection limit of 1.0 μg/mL for CGA in sample solution. The technique was used to analyze CGA concentration in green coffee extract, and the analytical results agree well with that obtained using a UV/Vis absorption spectrometric method. The real sample test results demonstrate the usefulness of this simple method for quick detecting CGA in green coffee extract products in field test applications.

Activation of NF-κB signaling in mesenchymal cells is common in LR-MDS.Activation of NF-κB in mesenchymal cells leads to transcriptional overexpression of inflammatory factors including negative regulators of hematopoiesis.Activation of NF-κB attenuates HSPC numbers and function ex vivo.

In order to improve our understanding of the interior structure of Saturn's small moon Enceladus, we reanalyze radiometric tracking and onboard imaging data acquired by the Cassini spacecraft during close encounters with the moon. We compute the global shape, gravity field, and rotational parameters of Enceladus in a reference frame consistent with the International Astronomical Union's definition, where the center of the Salih crater is located at −5° East longitude. We recover a quadrupole gravity field with J3and a forced libration amplitude of 0.091° ± 0.009° (3‐σ). We also compute a global shape model using a stereo‐photoclinometry technique with a global resolution of 500 m, although some local maps have higher resolutions ranging from 25 to 100 m. While our overall results are generally consistent with previous studies, we infer a thicker 27–33 km mean ice shell, a thinner 21–26 km mean ocean thickness, and a mean core density range of 2,270–2,330 kg/m3. Geodetic data, such as shape, gravity, and rotation, provide important constraints for probing a planetary body's interior structure. We analyze radiometric tracking and onboard imaging data acquired during close encounters of Enceladus by the Cassini spacecraft to compute geodetic products including topographic and gravitational fields in a common reference frame. The recovered Enceladus topography has a global resolution of 500 m, with some local regions having 25–100 m resolution. Our study suggests that Enceladus has a 27–33 km mean ice shell thickness, a 21–26 km mean ocean thickness, and a mean core density range of 2,270–2,330 kg/m3. A full quadrupole gravity field with J3and the forced libration amplitude of 0.091° ± 0.009° are recoveredA 500‐m resolution global topography model was computed, with some local regions having 25−100 m resolutionThe results suggest that Enceladus has a 27–33 km mean ice shell thickness, a 21–26 km ocean thickness, and a mean core density range of 2,270–2,330 kg/m3 A full quadrupole gravity field with J3and the forced libration amplitude of 0.091° ± 0.009° are recovered A 500‐m resolution global topography model was computed, with some local regions having 25−100 m resolution The results suggest that Enceladus has a 27–33 km mean ice shell thickness, a 21–26 km ocean thickness, and a mean core density range of 2,270–2,330 kg/m3

Dimethyl ether (DME, CH3OCH3) is one of the largest organic molecules detected in the interstellar gas and shows high abundances in star-forming regions, known as hot molecular cores. The observed DME might be formed on grains or by secondary gas phase reactions from a precursor molecule, which in turn was sublimed into the gas phase from the grain surface. Studies on the stability and degradation pathways of DME therefore provide important constraints on the evolutionary cycle of large organic molecules and chemical pathways in the interstellar medium. We studied the UV photodestruction rate of DME in a solid argon matrix. DME was destroyed with a half-life of 54 seconds under laboratory conditions, which corresponds to $8.3\times10 ^{5}$years in a dense cloud. We discuss the UV photochemistry of DME in the context of two issues: its formation mechanism and its chemistry in hot cores. Chemical models of shielded hot core regions indicate that UV photodestruction is relatively unimportant for DME, even by the internally-generated radiation field. These models clearly show that gas phase processes are almost certainly responsible for the formation of interstellar DME.

We have re-analyzed the 6–12 μm ISO spectrum of the ultra-luminous infrared galaxy Arp 220 with the conclusion that it is not consistent with that of a scaled up version of a typical starburst. Instead, both template fitting with spectra of the galaxies NGC 4418 and M 83 and with dust models suggest that it is best represented by combinations of a typical starburst component, exhibiting PAH emission features, and a heavily absorbed dust continuum which contributes ~40% of the 6–12 μm flux and likely dominates the luminosity. Of particular significance relative to previous studies of Arp 220 is the fact that the emission feature at 7.7 μm comprises both PAH emission and a broader component resulting from ice and silicate absorption against a heavily absorbed continuum. Extinction to the PAH emitting source, however, appears to be relatively low. We tentatively associate the PAH emitting and heavily dust/ice absorbed components with the diffuse emission region and the two compact nuclei respectively identified by Soifer et al. ([CITE]) in their higher spatial resolution 10 μm study. Both the similarity of the absorbed continuum with that of the embedded Galactic protostars and results of the dust models imply that the embedded source(s) in Arp 220 could be powered by, albeit extremely dense, starburst activity. Due to the high extinction, it is not possible with the available data to exclude that AGN(s) also contribute some or all of the observed luminosity. In this case, however, the upper limit measured for its hard X-ray emission would require Arp 220 to be the most highly obscured AGN known.

The 4.62 μm absorption band, observed along the line-of-sight towards various young stellar objects, is generally used as a qualitative indicator for energetic processing of interstellar ice mantles. This interpretation is based on the excellent fit with OCN-, which is readily formed by ultraviolet (UV) or ion-irradiation of ices containing H2O, CO and NH3. However, the assignment requires both qualitative and quantitative agreement in terms of the efficiency of formation as well as the formation of additional products. Here, we present the first quantitative results on the efficiency of laboratory formation of OCN-from ices composed of different combinations of H2O, CO, CH3OH, HNCO and NH3by UV- and thermally-mediated solid state chemistry. Our results show large implications for the use of the 4.62 μm feature as a diagnostic for energetic ice-processing. UV-mediated formation of OCN-from H2O/CO/NH3ice matrices falls short in reproducing the highest observed interstellar abundances. In this case, at most 2.7% OCN-is formed with respect to H2O under conditions that no longer apply to a molecular cloud environment. On the other hand, photoprocessing and in particular thermal processing of solid HNCO in the presence of NH3are very efficient OCN-formation mechanisms, converting 60%–85% and ~100%, respectively of the original HNCO. We propose that OCN-is most likely formed thermally from HNCO given the ease and efficiency of this mechanism. Upper limits on solid HNCO and the inferred interstellar ice temperatures are in agreement with this scenario.

Polar hydrogen deposits on the Moon provide evidence that its spin axis has shifted; analysis of the locations of these deposits and of the lunar figure suggests that the shift occurred as a result of changes in the Moon’s moments of inertia caused by a low-density thermal anomaly beneath the Procellarum region.

Mid infrared spectra provide a powerful probe of the conditions in dusty galactic nuclei. They variously contain emission features associated with star forming regions and absorptions by circumnuclear silicate dust plus ices in cold molecular cloud material. Here we report the detection of 6–8 μm water ice absorption in 18 galaxies observed by ISO. While the mid-IR spectra of some of these galaxies show a strong resemblance to the heavily absorbed spectrum of NGC 4418, other galaxies in this sample also show weak to strong PAH emission. The 18 ice galaxies are part of a sample of 103 galaxies with good $S/N$mid-IR ISO spectra. Based on our sample we find that ice is present in most of the ULIRGs, whereas it is weak or absent in the large majority of Seyferts and starburst galaxies. This result is consistent with the presence of larger quantities of molecular material in ULIRGs as opposed to other galaxy types. Like NGC 4418, several of our ice galaxy spectra show a maximum near 8 μm that is not or only partly due to PAH emission. While this affects only a small part of the galaxy population studied by ISO, it stresses the need for high $S/N$data and refined diagnostic methods, to properly discriminate spectra dominated by PAH emission and spectra dominated by heavy obscuration. The spectral variation from PAH emission to absorbed continuum emission near 8 μm shows strong similarities with Galactic star forming clouds. This leads us to believe that our classification of ice galaxy spectra might reflect an evolutionary sequence from strongly obscured beginnings of star formation (and AGN activity) to a less enshrouded stage of advanced star formation (and AGN activity), as the PAHs get stronger and the broad 8 μm feature weakens.

The $\rm \nu_3$feature of the $\rm OCN^-$ion near 2160 $\rm cm^{-1}$which is produced by acid-base reactions in cryogenic HNCO/$\rm NH_3$samples shows a small matrix induced deuterium shift. A similar shift is found for the "XCN" band near this position produced by photolysis of CO/$\rm NH_3$ice. This agreement, together with the abundant evidence already in the literature, clearly demonstrates that the XCN feature can be assigned to $\rm OCN^-$.

We present the first detection of the ${\nu_{\rm 3}}$ro-vibrational band of gas-phase ${\rm SO_2}$in absorption in the mid-infrared spectral region around 7.3${\rm \mu m}$of a sample of deeply embedded massive protostars. Comparison with model spectra shows that the derived excitation temperatures correlate with previous C2H2and HCN studies, indicating that the same warm gas component is probed. The ${\rm SO_2}$column densities are similar along all lines of sight suggesting that the ${\rm SO_2}$formation has saturated, but not destroyed, and the absolute abundances of ${\rm SO_2}$are high (~10-7). Both the high temperature and the high abundance of the detected ${\rm SO_2}$are not easily explained by standard hot core chemistry models. Likewise, indicators of shock induced chemistry are lacking.

We investigate the 2-3${\rm \mu m}$ISO-SWS spectrum of the luminous protostellar object S 140:IRS1. Two narrow absorption features are detected at 2.70 and 2.77 μm, which are well fitted with laboratory spectra of the ${\rm \nu_1 + \nu_3}$and the ${\rm 2\nu_2 + \nu_3}$combination modes of solid ${\rm CO_2}$. The ice in this line of sight must have been subjected to significant heating, in agreement with previously studied CO2bands. A combined laboratory fit to all CO2bands detected toward S 140:IRS1 shows, among others, the need for particle shape calculations for the CO2stretch mode. Finally, we discuss the absence of features of isolated H2O and dangling OH groups in the spectrum of S 140:IRS1.

We have obtained 5-8 ${\rm \mu m }$spectra towards 10 embedded protostars using the Short Wavelength Spectrometer on board the Infrared Space Observatory (ISO-SWS) with the aim of studying the composition of interstellar ices. The spectra are dominated by absorption bands at 6.0 ${\rm \mu m }$and 6.85 μm. The observed peak positions, widths and relative intensities of these bands vary dramatically along the different lines of sight. On the basis of comparison with laboratory spectra, the bulk of the 6.0 ${\rm \mu m }$absorption band is assigned to amorphous H2O ice. Additional absorption, in this band, is seen toward 5 sources on the short wavelength wing, near 5.8 μm, and the long wavelength side near 6.2 μm. We attribute the short wavelength absorption to a combination of formic acid (HCOOH) and formaldehyde (H2CO), while the long wavelength absorption has been assigned to the C-C stretching mode of aromatic structures. From an analysis of the 6.85 ${\rm \mu m }$band, we conclude that this band is composed of two components: a volatile component centered near 6.75 ${\rm \mu m }$and a more refractory component at 6.95 μm. From a comparison with various temperature tracers of the thermal history of interstellar ices, we conclude that the two 6.85 ${\rm \mu m }$components are related through thermal processing. We explore several possible carriers of the 6.85 ${\rm \mu m }$absorption band, but no satisfactory identification can be made at present. Finally, we discuss the possible implications for the origin and evolution of interstellar ices that arise from these new results.

We report the detection of absorption features in the 6-8 μm region superimposed on a featureless mid-infrared continuum in NGC 4418. For several of these features this is the first detection in an external galaxy. We compare the absorption spectrum of NGC 4418 to that of embedded massive protostars and the Galactic centre, and attribute the absorption features to ice grains and to hydrogenated amorphous carbon grains. From the depth of the ice features, we infer that the powerful central source responsible for the mid-infrared emission must be deeply enshrouded. Since this emission is warm and originates in a compact region, an AGN must be hiding in the nucleus of NGC 4418.

The JunoExtended Mission presented the first opportunity to acquire gravity measurements of Ganymede since the end of the Galileomission. These new Junodata offered the chance to carry out a joint analysis with the Galileodata set, improving our knowledge of Ganymede's gravity field and shedding new light upon its interior structure. Through reconstruction of Juno's and Galileo's orbit during the Ganymede flybys, the gravity field of the moon was estimated. The results indicate that Ganymede's degree‐2 field is compatible with a body in hydrostatic equilibrium within 1−𝜎and hint at regional gravity anomalies with amplitudes exceeding those inferred by Cassinifor Titan. Our explicit treatment of non‐hydrostatic effects leads to wider confidence intervals for the derived moment of inertia with respect previous analyses. The higher central value of the derived moment of inertia indicates a lesser degree of Ganymede's differentiation. On 7 June 2021, Junoperformed the first close flyby of Ganymede, the largest satellite of Jupiter (and the largest moon in the Solar System), since the end of the Galileomission. The gravity field of Ganymede was reconstructed using the radio tracking data from all of the Ganymede encounters of both the Galileoand Junomissions. The data analysis hints at localized gravity anomalies. Interpretation of the gravity data suggests a slightly higher moment of inertia with respect previous publications, indicating a lesser degree of differentiation. Joint analysis of the Junoand Galileodata leads to a Ganymede's degree‐2 gravity compatible with hydrostatic equilibrium within 1−σThe data hints at regional gravity anomalies with amplitudes exceeding those inferred by Cassinifor TitanTreatment of non‐hydrostatic effects leads to wider confidence intervals for the derived moment of inertia with respect to previous studies Joint analysis of the Junoand Galileodata leads to a Ganymede's degree‐2 gravity compatible with hydrostatic equilibrium within 1−σ The data hints at regional gravity anomalies with amplitudes exceeding those inferred by Cassinifor Titan Treatment of non‐hydrostatic effects leads to wider confidence intervals for the derived moment of inertia with respect to previous studies

The Cameroon Volcanic Line (CVL) straddles the continent‐ocean boundary in West Africa but exhibits no clear age progression. This renders it difficult to explain by traditional plume/plate motion hypotheses; thus, there remains no consensus on the processes responsible for its development. To understand better the nature of asthenospheric flow beneath the CVL, and the effects of hotspot tectonism on the overlying lithosphere, we analyze mantle seismic anisotropy and seismicity. Cameroon is relatively aseismic compared to hotspots elsewhere, with little evidence for magmatism‐related crustal deformation away from Mount Cameroon, which last erupted in 2000. Low crustal Vp/Vsratios (∼1.74) and a lack of evidence for seismically anisotropic aligned melt within the lithosphere both point toward a poorly developed magmatic plumbing system beneath the CVL. Null SKSsplitting observations dominate the western continental portion of the CVL; elsewhere, anisotropic fast polarization directions parallel the strike of the Precambrian Central African Shear Zone (CASZ). The nulls may imply that the convecting upper mantle beneath the CVL is isotropic, or characterized by a vertically oriented olivine lattice preferred orientation fabric, perhaps due to a mantle plume or the upward limb of a small‐scale convection cell. Precambrian CASZ fossil lithospheric fabrics along the CVL may have been thermomechanically eroded during Gondwana breakup ∼130 Ma, with an isotropic lower lithosphere subsequently reforming due to cooling of the slow‐moving African plate. Small‐scale lithospheric delamination during the 30 Ma recent development of the line may also have contributed to the erosion of the CASZ lithospheric fossil anisotropy, at the same time as generating the low‐volume alkaline basaltic volcanism along the CVL. Seismicity along the CVL is focused around Mt. CameroonCVL magmatism has had little impact on the overlying lithosphereLithospheric delamination is an appropriate candidate for CVL development

Evidence from Arrokoth and comets strongly suggests a very low density for this and similar small Kuiper belt objects. Plausible compositions imply high porosities, in excess of 70%, and low compaction crush strengths. If so, impact craters on Arrokoth (especially Sky, its largest) formed largely by compaction of pore space and material displacement. This is consistent with geological evidence from New Horizonsimaging. High porosity reduces cratering efficiency in the gravity regime whereas compaction moves it toward crush strength scaling and increased efficiency. Compaction also guarantees that most impactor kinetic energy is taken up as waste heat near the impact point, with momentum transferred to the rest of the body by elastic waves only. Monte Carlo simulations of Sky‐forming conditions indicate that the momentum imparted likely separated Arrokoth's two lobes, but displacement was limited by dissipation at the neck between them. Unusual strength properties are not required to preserve Arrokoth's bilobate configuration. It has become apparent over the last few years that small asteroids and comets are very underdense compared with the materials they are made of. This means that their total porosities are likely quite high, in excess of 70%, both as tiny voids within particles (so‐called microscopic porosity) and spaces between particles (macroscopic porosity). But none are likely as porous as the distant denizens of the Kuiper belt such as Arrokoth (visited by the New Horizonsspacecraft in 2019). This paper concerns impact craters on Arrokoth and similar small bodies, and the rather unusual effects expected. Imagine a fluffy (fine powder) snowball striking a much larger fluffy snowball, only that the snow is not pure ice but a mixture of porous icy, rocky, and carbon‐rich particles. Even at high velocities (>100 s of m/s) craters should mostly form by compacting pore space and pushing material away from the impact point, not the traditional blasting of ejecta back into space. Similar to crush‐up of an automobile bumper, compaction helps to protect from the potentially catastrophic effects of large impacts, such as complete disruption of the target or breakup of bilobate bodies like Arrokoth, and should be incorporated in future collisional evolution studies. Arrokoth is likely a low density, highly porous, contact binary planetesimalImpact craters on Arrokoth, and particularly its largest, likely formed as compaction craters, with modest or little ejectaHigh porosity acted to protect Arrokoth from catastrophic disruption, ejecta recoil, and lobe dislocation and rearrangement Arrokoth is likely a low density, highly porous, contact binary planetesimal Impact craters on Arrokoth, and particularly its largest, likely formed as compaction craters, with modest or little ejecta High porosity acted to protect Arrokoth from catastrophic disruption, ejecta recoil, and lobe dislocation and rearrangement

This paper reports on a methodology to achieve low-cost high-efficiency screen-printed low-to-medium concentrator Si cells and validates it by fabricating some of the highest efficiency metal paste printed cells with a simple cell design. The model shows that the highest achievable efficiency at any given concentration is a function of metal paste, contact parameters, number of fingers, and finger length due to the tradeoff between resistive and shadow losses. Consistent with the model calculations, first, 52 mm × 27 mm ~19% cells were fabricated at ~5X (suns) with a Dupont 16 A paste and ~110 μm wide 32 lines. Then, with improved 50 μm wide direct extrusion printed fingers, >20% efficient cells were achieved in the concentration range of 3-16X, along with a roadmap to ~21% efficient cells. This approach provides excellent guidelines to design grid pattern and selecting cell dimensions to achieve maximum efficiency at the desired concentration from a given printing technology and cell structure.

β-Peptides (β-amino acid oligomers) that mimic the amphiphilic, helical, and cationic properties of natural antimicrobial peptides have previously been shown to display antifungal activity against planktonic Candida albicanscells. β-Peptides offer several advantages over conventional peptides composed of α-amino acid residues, including conformational stability, resistance to proteases, and activity at physiological salt concentrations. We examined sequence–activity relationships toward both planktonic C. albicanscells and C. albicansbiofilms, and the results suggest a toxicity mechanism involving membrane disruption. A strategy for fluorescently labeling a β-peptide without diminishing antifungal activity was devised; labeled β-peptides penetrated the cell membrane and accumulated in the cytoplasm of both planktonic and biofilm-associated cells. The labeled β-peptide was detected only in metabolically inactive cells, which suggests that β-peptide entry is correlated with cell death. The presence of a β-peptide at a concentration near the minimum inhibitory concentration completely prevented planktonic C. albicanscells from forming a biofilm, suggesting that β-peptides may be useful in preventing fungal colonization and biofilm formation.

Electronic Patient Records systems configured into large enterprise models have become the assumed best route forward. In England, as in several other countries, this has expanded to a major meta-enterprise procurement programme. However, concerns are raised that such systems lack user ownership, and experience from other sectors shows difficulties with large enterprise systems. At a time of great change and once again shifting organizations, is this move simply building large and ponderous edifices with unstable materials? Latest software engineering research is now demonstrating the potential of an alternative model, enabling trusted information brokers to search out in real time at point of use data held in registered local and departmental systems. If successful, this could enable a new and less cumbersome paradigm. The data could move where needed whatever the service configuration. A concept demonstrator has been built set in the context of health and social care in England. It is important for all technological support to the health sector to be reviewed as new technologies emerge so as to identify and exploit new opportunities, and the results of this 3 year project show that the health record information broker route merits further investigative research.

Newer TNF blockers (etanercept, infliximab and adalimumab) have contributed greatly to the control of chronic inflammatory disease. Many of the damaging inflammatory mechanisms that they inhibit are, however, important in maintaining tuberculosis in the latent phase (latent tuberculosis infection or LTBI). There is considerable evidence that links reactivation of LTBI to the use of anti-TNF monoclonal antibody (mAb) treatments, which appear to result in disruption of the granuloma that normally compartmentalizes but does not kill Mycobacterium tuberculosis during LTBI. This effect can be explained, in part, by directly neutralizing TNF, which plays a key role in tuberculosis immunity. To the clinician, dealing with LTBI in patients on these medications is an important issue. Prescribers should seek local expert help in this regard, as global LTBI treatment regimens differ. Nonetheless, screening for and treating LTBI will prevent reactivation in most patients. LTBI screening should include a careful history, tuberculin skin test and chest radiograph. Prophylactic treatment (e.g. isoniazid for 9 months) should be offered to patients with LTBI, in accordance with local advice. False-negative tuberculin skin test results can be expected in these patient groups. False-negative skin tests also mean that clinicians cannot be complacent about patients on TNF blockers who lack evidence of LTBI. On the contrary, because tuberculosis disease can be lethal, all treated patients should be advised to seek medical attention if symptoms suggestive of tuberculosis emerge. The indications for these successful agents are expanding, and efficient management of the LTBI issue should improve their safety profile.

A new generation of dearomatizing π-bases having the general form {TpM(L)(π-acid)} (where Tp = hydridotris(pyrazolyl)borate, M = rhenium, molybdenum, tungsten, L = variable ligand, and π-acid = CO, NO⁺) has been developed. These fragments show reactivity patterns similar to those of their pentaammineosmium(II) predecessor, binding aromatic molecules across two carbons and subsequently activating these ligands toward electrophilic addition and cycloaddition reactions. In many cases, these second-generation dearomatization agents show a greater degree of π-back-bonding than was observed for the analogous pentaammineosmium(II) complexes. A number of unprecedented reaction pathways have been discovered for these second-generation systems, most notably a broad array of cyclization reactions. In addition, these chiral-at-metal dearomatization agents are readily resolved and have been utilized in reaction sequences to give highly enantioenriched polycyclic molecules from common aromatic precursors.

A series of complexes of the form TpMo(NO)(L)(η²-Lπ) were synthesized, where Tp = hydridotris(pyrazolyl)borate, L = 1-methylimidazole or ammonia, and Lπ is an alkene, alkyne, ketone, polyaromatic hydrocarbon, or aromatic heterocycle. The thermal stability of the dihapto-coordinated aromatic complexes is indicative of a strong π back-bonding interaction similar to that found in the heavy metal analogues [Os(NH3)5(η²-arene)]²⁺, TpRe(CO)(L)(η²-arene), and TpW(NO)(L)(η²-arene). Several synthetic routes to these molybdenum complexes are outlined.

This paper presents, for the first time, a complete 2.4-25 ?m spectrum of the dust-embedded young stellar object W33A. The spectrum was obtained with the Short Wavelength Spectrometer of the Infrared Space Observatoryat a mean resolving power of ~750. The spectrum displays deep H2O ice and silicate absorptions centered at 3.0 and 9.7 ?m, respectively, together with absorption features identified with various other molecules in the solid phase. The 2.4-5.0 ?m region of the spectrum is used to investigate the long-standing problem of the H2O ice column density toward W33A, by means of the stretching and combination mode features at 3.0 and 4.5 ?m. Although no flux is seen at the center of the 3.0 ?m feature, its central depth may be constrained by fitting assumed profiles to the short- and long-wavelength wings in our spectrum. We deduce that a value of N(H2O) = (1.1 ± 0.3) × 1019cm-2is consistent with these features, a factor of at least 3 less than predicted by the H2O bending mode at 6.0 ?m; the reason for this discrepancy is unclear. We report new results on the abundances of nitrogen-bearing species in the ices toward W33A. Solid NH3is detected for the first time in this line of sight, by means of the inversion-mode feature at 9.0 ?m. The column density is N(NH3) = (1.7 ± 0.4) × 1018cm-2, implying an abundance of ~15% relative to H2O, comparable to that recently reported toward the young star NGC 7538 IRS 9. However, we find no convincing evidence for absorptions associated with the C?N stretching mode of nitriles in the 4.4-4.6 ?m region of the spectrum. If nitriles are present in the ices along this line of sight, they must have column density no more than ~1017cm-2or ~1% relative to H2O. This argues against identification of the deep 4.62 ?m `XCN' feature with isonitriles, as an implausibly low nitrile to isonitrile abundance ratio (<0.1) would be implied. New and previously published results are combined to construct an inventory of column densities and abundances (normalized to H2O) for all known species detected in molecular ices toward W33A. A band strength appropriate to the cyanate ion is assumed to provide quantitative results for XCN. Results are compared with those for other well-studied lines of sight, including the Taurus field star Elias 16, the Galactic center source Sgr A*, and the young stellar objects NGC 7538 IRS 9, GL 2136, and GL 7009S. The CO and XCN abundances are used as indicators of thermal and energetic processing, respectively (where energetic processing may include either UV photolysis or energetic ion bombardment). Abundances for CH3OH vary from below 3% in unprocessed ices to ~20%-30% in W33A and GL 7009S, consistent with formation by energetic processing. In contrast, CH4shows little evidence of variation. Abundance data for cometary ices indicate some general similarities with interstellar and protostellar ices. CO and CH3OH show comet-to-comet variations that may provide clues to their origins. The highest CH3OH concentrations in comets are comparable with average values for interstellar/protostellar ices.

Setting: Mycobacterium aviumis the major cause of disseminated infection in patients with late stage AIDS.

A combination of fluorescent retrograde tracers and horseradish peroxidase (HRP) was used to compare the spinal distributions of motoneurons supplying shoulder muscles with attachments to the skull and cervical spinal cord that suggest a significant role in head movement. Two muscles, the rhomboideus and the levator scapulae, were innervated by multiple segmental nerve bundles that entered the muscles at different rostrocaudal locations. Motoneurons that were labelled retrogradely from rhomboideus nerve bundles formed a single, long column in the ventral horn from C4 to C6, lateral to previously studied motor nuclei supplying deep neck muscles. When different tracers were used to differentiate motoneurons supplying specific nerve bundles, discrete subnuclei could be identified that were organized in a rostrocaudal sequence corresponding to the rostrocaudal order of the nerve bundles. Levator scapulae motoneurons formed a second elongate column immediately lateral to the rhomboideus motor nucleus. Three other muscles, the trapezius, sternomastoideus, and cleidomastoideus, were supplied by cranial nerve XI. Labelled motoneurons from these muscles formed a single column from the spinomedullary junction to middle C6. Within this column, the three motor nuclei supplying the sternomastoideus, cleidomastoideus, and trapezius were laminated mediolaterally. Sternomastoideus and cleidomastoideus motoneurons were confined to upper cervical segments, whereas trapezius motoneurons were found from C1 to C6. In C1 and C6, the motoneuron column was located centrally in the gray matter, but, between C2 and C5, the column lay on the lateral wall of the ventral horn in a position dorsolateral to motor nuclei supplying the rhomboideus and the deeper neck muscles. The findings in this study suggest that descending and propriospinal systems responsible for coordinating head movement may have to descend as far caudally as C6 if they are to project onto muscles controlling the mobility of the lower neck. J. Comp. Neurol. 377:298–312, 1997. © 1997 Wiley‐Liss, Inc.

The effect of Mycobacterium tuberculosis infection on the viability of healthy (control) human alveolar macrophages was evaluated by staining with ethidium homodimer and calcein to discriminate live from dead cells. Infection with M. tuberculosis H37Ra or H37Rv increased macrophage mortality at 6 days from the control level of 3.8% +/- 0.7% to 28.7% +/- 6.9% or 12.6% +/- 3.1%, respectively (P < 0.001 for comparisons of all conditions). A role for tumor necrosis factor alpha (TNF-alpha) in the M. tuberculosis-induced cytolysis of alveolar macrophages was demonstrated by increased cytotoxicity following the addition of exogenous TNF-alpha to the cultures and by enhancement of macrophage survival when M. tuberculosis-infected alveolar macrophages were treated with pentoxifylline or anti-TNF-alpha antibody. The cytolytic mechanism was determined to be apoptosis by the demonstration of a characteristic internucleosomal ladder of genomic DNA by agarose gel electrophoresis, by finding nuclear fragmentation and condensation by electron microscopy, and by in situ terminal transferase-mediated nick end labeling of fragmented DNA in alveolar macrophages infected with M. tuberculosis in vitro. The latter technique was employed to reveal extensive apoptosis within caseating granulomas from lung tissue samples from clinical tuberculosis cases. The induction of apoptosis in alveolar macrophages by M. tuberculosis may play a role in the macrophage-pathogen interaction of tuberculosis in vivo.

Apolipoprotein H (ApoH) is a 50 kDa glycoprotein capable of binding to negatively charged phospholipids and is a probable inhibitor of the blood coagulation pathway, platelet aggregation, and platelet prothrombinase activity, as well as being involved in autoimmune disease. We have cloned and sequenced a full length ApoH cDNA clone from a beagle dog liver library. Its derived amino acid sequence shows high cross-species similarity to ApoH from other mammals. Canine ApoH mRNA expression is down regulated during an experimentally induced inflammatory response establishing that it is a negative acute phase reactant.

Abstract: We developed a detached leaf method for evaluating potato (Solanum tuberosum L.) and tomato (Lycopersicon esculentum Mill.) germplasm for reactions toPhytophthora infestans, the causal organism of late blight. Primary leaves from the third to the sixth node of potato plants, and the fourth to sixth node of tomato plants were excised at the stem. Their petioles were inserted into 14 mm × 100 mm floral aqua tubes containing 9 ml of sterilized distilled water. The leaves in the aqua tubes were placed with abaxial sides down on galvanized metal hardware cloth (12.5 × 12.5 mm mesh). A 12.5 mm sensi-disc containing 50μl of 2 × 104 zoospores was placed in the centers of the terminal leaflet and the second leaflet pair of the potato leaf. A single disc was placed on the center of the tomato leaf. The supporting hardware cloth was placed 2.5 cm above distilled water (2.5 cm deep) in 31 cm × 17 cm × 8 cm clear plastic boxes with tight fitting lids. Leaves on intact tomato and potato plants were inoculated in a similar manner and placed in a mist chamber. Lesion growth was determined 4, 5, and 6 days following inoculation. There were no significant differences in reactions to isolates ofP. infestans on detached and intact leaves of potato cultivars Green Mountain and Kennebec and the tomato cultivar Bonnie Best.

The effect of Mycobacterium tuberculosis infection on the viability of healthy (control) human alveolar macrophages was evaluated by staining with ethidium homodimer and calcein to discriminate live from dead cells. Infection with M. tuberculosis H37Ra or H37Rv increased macrophage mortality at 6 days from the control level of 3.8% +/- 0.7% to 28.7% +/- 6.9% or 12.6% +/- 3.1%, respectively (P < 0.001 for comparisons of all conditions). A role for tumor necrosis factor alpha (TNF-alpha) in the M. tuberculosis-induced cytolysis of alveolar macrophages was demonstrated by increased cytotoxicity following the addition of exogenous TNF-alpha to the cultures and by enhancement of macrophage survival when M. tuberculosis-infected alveolar macrophages were treated with pentoxifylline or anti-TNF-alpha antibody. The cytolytic mechanism was determined to be apoptosis by the demonstration of a characteristic internucleosomal ladder of genomic DNA by agarose gel electrophoresis, by finding nuclear fragmentation and condensation by electron microscopy, and by in situ terminal transferase-mediated nick end labeling of fragmented DNA in alveolar macrophages infected with M. tuberculosis in vitro. The latter technique was employed to reveal extensive apoptosis within caseating granulomas from lung tissue samples from clinical tuberculosis cases. The induction of apoptosis in alveolar macrophages by M. tuberculosis may play a role in the macrophage-pathogen interaction of tuberculosis in vivo.

We examine the nature of requirements on parallel total systems and the problem of documenting those requirements formally. The choice of the formal description method to be used should take into account the nature of the system to be developed and the benefits that method will bring to the provision of requirements in that particular project.

This article discusses a three‐way cooperative test that was instrumental in the Ambridge Water Authority adopting a more effective paint system (SSPC‐Paint System No. 4.00, vinyl paint system over sand‐blasted steel). It has been conservatively estimated that this system has increased the average trouble‐free life of paint on the interior of water tanks from 3 to more than 8 years, with a 50 per cent savings in annual painting costs.

Hold-up of solution by the solids undergoing extraction has been shown to be an important factor in the design of percolation extraction systems. By means of a laboratory technique, hold-up was measured for a wide variety of prepared oilseeds. Empirical correlations of the data were obtained, and their significance was illustrated in a sample design calculation.

Summary: Hold-up of solution by the solids undergoing extraction has been shown to be an important factor in the design of percolation extraction systems. By means of a laboratory technique, hold-up was measured for a wide variety of prepared oilseeds. Empirical correlations of the data were obtained, and their significance was illustrated in a sample design calculation.

In the investigation of minor incidents involving the spread of radioactivity at atomic energy establishments, identification and measurement is required of the radioactive nuclides involved. These measurements assist in estimating the magnitude of the release and in discovering its source. Examples are given of the role of alpha, beta and gamma spectrometry in Health Physics investigations of such incidents at A.E.R.E. Harwell. Among the items discussed are the contamination of reactor areas by fission products and the activation of reactor construction materials, the spread of fission product activity in disposal operations and the identification of activity in external body contamination. In these and in other cases spectrometry has been found to be a powerful tool for the rapid analysis of radioactive samples.

To investigate the performance that can be achieved for low energy heavy ion particle acceleration, a two megahertz low beta linac is being built. This structure, intended for acceleration of 260 keV xenon or 400 keV mercury, is comprised of a quarter wavelength parallel plate resonator used to support drift tubes forming a ß¿/2 structure. The 20 gap accelerator, to be driven by a 30 kilowatt transmitter, will provide 10 milliamperes of mercury ions at the 1.8 MeV energy level. Focussing is achieved by a unique arrangement of electrostatic quadrupoles. A plan view of the accelerating system is shown in Figure 1.