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This paper brings contemporary debate in analytic philosophy of religion regarding the notion of worship into conversation with Jewish sources and attempts to identify the most promising philosophical grounds for a Jewish account of the putative obligatoriness of worship. Some philosophers have recently debated the notion of worship, focusing in particular on the claim that human beings have an obligation to worship God and on whether and how such an obligation might be adequately grounded. I first canvass the major bases for worshipping God that have featured in this debate. I then turn to some relevant liturgical and philosophical sources of Jewish tradition, identifying grounds for the obligatoriness of (exclusively) worshipping God that have been advanced in those sources. I next consider which grounds of the putative obligatoriness of worship are the most promising for a Jewish account in terms of both philosophical cogency and rootedness in Jewish tradition. I argue that a version of a divine command grounding of prayer in a Soloveitchikian mode is both well-rooted in Judaism and also plausibly surmounts philosophical objections to divine command accounts. In the final section, I briefly raise the issue of whether the concept of worship is truly well-suited to a Jewish context, suggesting that the rich Hebrew notions of avodah and tefillah are perhaps more appropriate in articulating a fully adequate Jewish understanding of the pertinent issues. In particular, I argue that these notions fit well with the Soloveitchikian divine command grounding of the obligation to worship God.

T cells discriminate between healthy and infected cells with remarkable sensitivity when mounting an immune response, which is hypothesized to depend on T cells combining stimuli from multiple antigen‐presenting cell interactions into a more potent response. To quantify the capacity for T cells to accomplish this, we have developed an antigen receptor that is optically tunable within cell conjugates, providing control over the duration, and intensity of intracellular T‐cell signaling. We observe limited persistence within the T‐cell intracellular network on disruption of receptor input, with signals dissipating entirely in ~15 min, and directly show sustained proximal receptor signaling is required to maintain gene transcription. T cells thus primarily accumulate the outputs of gene expression rather than integrate discrete intracellular signals. Engineering optical control in a clinically relevant chimeric antigen receptor (CAR), we show that this limited signal persistence can be exploited to increase CAR‐T cell activation threefold using pulsatile stimulation. Our results are likely to apply more generally to the signaling dynamics of other cellular networks., An optically controllable chimeric antigen receptor is developed for modulating T cell signaling dynamics. Limited signal persistence is found at key nodes in the intracellular network, constraining the window over which T cells can integrate discrete activation signals.

SUMMARYT cells discriminate between healthy and infected cells with remarkable sensitivity when mounting an immune response. It has been hypothesized that this efficient detection requires combining signals from discrete antigen-presenting cell interactions into a more potent response, requiring T cells to maintain a ‘memory’ of previous encounters. To quantify the magnitude of this phenomenon, we have developed an antigen receptor that is both optically and chemically tunable, providing control over the initiation, duration, and intensity of intracellular T-cell signaling within physiological cell conjugates. We observe very limited persistence within the T cell intracellular network on disruption of receptor input, with signals dissipating entirely in ~15 minutes, and directly confirm that sustained proximal receptor signaling is required to maintain active gene transcription. Our data suggests that T cells are largely incapable of integrating discrete antigen receptor signals but instead simply accumulate the output of gene expression. By engineering optical control in a clinically relevant chimeric antigen receptor, we show that this limited signal persistence can be exploited to increase the activation of primary T cells by ~3-fold by using pulsatile stimulation. Our results are likely to apply more generally to the signaling dynamics of other cellular networks.

An investigation considering the efficiency gains of electrical pulse-shaping for a two-stage reluctance accelerator system has been undertaken. An optimum gross efficiency of (1.36 ± 0.02)% was achieved, amounting to an increase of (290 ± 20)% relative to the performance of an equivalent single-stage accelerator. The performance increase due to pulse-shaping for a two-stage setup was found to surpass that achieved for this single-stage setup in terms of both efficiency and velocity. This investigation highlights the potential of pulse-shaping methods to increase the feasibility and flexibility of electrical acceleration for a variety of practical applications. The intention of this paper was to exhibit the potential of reluctance acceleration technology in multi-stage, initially by using a two-stage system. Possible avenues for further investigation are proposed, to build upon the results of this study.

Introduction: Both physical therapy (PT) and surgery appear to have some efficacy in treating femoroacetabular impingement (FAI). Only recently have high-level evidence studies compared these two options, though results of these randomized controlled trials (RCTs) are contradictory. The purpose of this study was to perform a systematic review and meta-analysis of RCTs comparing PT and surgery in patients with FAI. Methods: A systematic review was performed to identify randomized trials comparing FAI and PT. Data was extracted for demographics, study design, patient reported outcomes (PROs), and study quality/bias. In total, 819 abstracts were reviewed, with three RCTs identified (Griffin 2018, Mansell 2018, and Palmer 2019). All three RCTs reported iHOT-33, while two studies reported HOS ADL and Sport (Mansell 2019 and Palmer 2019). In a random effects meta-analysis, between-group differences in post-intervention scores were assessed using intention-to-treat analysis in each study. Results: All 3 RCTs reported PROs improvement from baseline to follow-up for both PT and surgery. The meta-analysis demonstrated greater improved iHOT-33 outcomes with surgery compared to PT with a mean relative difference of 11.3 (95% CI 1.86-20.73, p=0.014). The meta-analysis for HOS ADL and Sports (two RCTs) similarly demonstrated higher scores with surgery with a mean difference of 3.9 (95% CI -9.6-17.3, p=0.571) and 6.2 (95% CI -6.8-19.2, p=0.347), respectively, though without statistical significance. The quality of two RCTs was assessed as good with minimal bias (Griffin and Palmer). In the third RCT, an extremely high crossover rate may affect its validity (Mansell 2018, 70% crossover from PT to surgery). For instance, HOS ADL outcome based on treatment received, adjusting for Mansell’s crossover rate, favored surgery with a larger mean difference of 12.0 (95% CI 7.5-16.5, pDiscussion: In patients with FAI, combined results of three RCTs demonstrate superior outcomes of surgery compared to PT. However, PT can result in improvements in some patients and does not appear to compromise surgical outcomes. Provided that the studies adjusted for certain patient characteristics, further research needs to identify patient characteristics that predict success of non-operative and operative treatment of FAI in specific patient subgroups. [Figure: see text]

In the field of structural dynamics, real-time hybrid simulation (RTHS) continues to receive increased interest from researchers conducting component testing incorporating system-level behaviour. Increased digital computing power has allowed advances in RTHS. However, limitations in RTHS will persist due to the effects of discrete errors caused by quantisation and corresponding numerical integration time step limitations, which can limit the bandwidth and nonlinearities of the system studied. In this paper, an analogue electronic computer is constructed to conduct RTHS of a modelled base-isolated structure with a physically tested viscous damping device. The analogue computer models a two-degree-of-freedom (2DOF) structure and solves the equations of motion required in RTHS testing. Results of the RTHS tests using the analogue computer are compared to RTHS tests implemented with a digital computer in order to validate the proposed analogue RTHS method. Further applications of RTHS testing with analogue computing including high-frequency dynamic testing are discussed.

The bacterial chemoreceptor complex governs signal detection and the upstream elements of chemotactic behavior, but the detailed molecular mechanism is still unclear. We have assembled nativelike functional arrays of an aspartate receptor cytoplasmic fragment (CF) with its two cytoplasmic protein partners (CheA and CheW) for solid-state nuclear magnetic resonance (NMR) studies of structural changes involved in signaling. In this initial study of the uniformly (13)C- and (15)N-enriched CF in these13.8 MDa size arrays, residue-type assignments are made for amino acids that together make up 90% of the protein. We demonstrate that homo- and heteronuclear two-dimensional spectra are consistent with structure-based chemical shift predictions: a number of major assignable correlations are consistent with the predominantly α-helical secondary structure, and minor correlations are consistent with the disordered C-terminal tail. Sub-parts per million line widths and spectral changes upon freezing of samples suggest these arrays are structurally homogeneous and sufficiently immobilized for efficient solid-state NMR.

Wood Storks (Mycteria americana) were first recorded nesting in Georgia in 1965 at Blackbeard Island National Wildlife Refuge (Harris 1995). In 1992, biologists initiated annual aerial surveys of known wading bird rookery sites to document Wood Stork distribution and estimate the number of nesting pairs in Georgia. Additionally, personnel from the U.S Fish and Wildlife Service and Savannah River Ecology Laboratory have contributed annual ground-count data for several colonies. Since surveys began, stork nesting has been documented at least once in 43 locations across the Coastal Plain of the state, with an average of 14 active sites per year. The documented nesting effort for storks has increased from four pairs in one wading bird colony in 1965 to a high count of 1,817 pairs in 19 colonies in 2005. A regression of log-transformed nest totals for the 14-year time-series (1992-2005) showed no significant overall trend in nesting pair numbers (P = 0.84) for that period. However, it is possible that...

Much ink has been spilt over the question of “Nietzsche and the Jews” ever since the distortion of Nietzsche's manuscripts by his sister, Elizabeth Förster-Nietzsche, forged the links with Nazism that would be further developed by the likes of Alfred Bäumler into a “carefully orchestrated cult.” Though it is a portrait long dismissed in the academic world, a combination of Nazi propaganda and some subsequent scholarship has ensured that the picture of Nietzsche as a virulent anti-Semite who provided Nazism with its conceptual underpinnings lingers in the popular mind. Most scholars, however, now accept at worst a more ambivalent picture. Others go beyond ambivalence, with Weaver Santaniello turning the accusation of anti-Semitism on its head by arguing that Nietzsche's contempt for anti-Semitism was one of the driving forces behind his critique of liberal Christianity, which in its use of “conservative theological concepts . . . perpetuate[s] anti-Semitism.” Even Crane Brinton, arguably one of those scholars most responsible for perpetuating the misrepresentation of Nietzsche as an anti-Semite, insisted that he had never maintained “that Nietzsche was a ‘proto-Nazi’.” But whilst Nietzsche is almost universally exonerated from the charge of personal anti-Semitism, Brinton's claim that “occasionally [Nietzsche] comes very close indeed to the Nazi program,” though based on poor use of Nietzsche's writings and rightly dismissed by Walter Kaufmann, continues to find echoes even amongst more careful Nietzsche scholars, who claim that he “did have some responsibility for Nazi crimes.”

We present a measurement of the sky distribution of positronium (Ps) annihilation continuum emission obtained with the SPI spectrometer on board ESA's INTEGRAL observatory. The only sky region from which significant Ps continuum emission is detected is the Galactic bulge. The Ps continuum emission is circularly symmetric about the Galactic centre, with an extension of about 8 deg FWHM. Within measurement uncertainties, the sky distribution of the Ps continuum emission is consistent with that found by us for the 511 keV electron-positron annihilation line using SPI. Assuming that 511 keV line and Ps continuum emission follow the same spatial distribution, we derive a Ps fraction of 0.92 +/- 0.09. These results strengthen our conclusions regarding the origin of positrons in our Galaxy based on observations of the 511 keV line. In particular, they suggest that the main source of Galactic positrons is associated with an old stellar population, such as Type Ia supernovae, classical novae, or low-mass X-ray binaries. Light dark matter is a possible alternative source of positrons., accepted for publication by A&A

It is believed that core-collapse supernovae (CCSN), occurring at a rate about once per century, have seeded the interstellar medium with long-lived radioisotopes such as 60Fe (half-life 1.5 Myr), which can be detected by the gamma rays emitted when they beta-decay. Here we report the detection of the 60Fe decay lines at 1173 keV and 1333 keV with fluxes 3.7 +/- 1.1 x 10(-5) ph cm(-2) s(-1) per line, in spectra taken by the SPI spectrometer on board INTEGRAL during its first year. The same analysis applied to the 1809 keV line of 26Al yielded a line flux ratio 60Fe/26Al = 0.11 +/- 0.03. This supports the hypothesis that there is an extra source of 26Al in addition to CCSN.

This article describes three studies in prosody and their potential application to the field of forensic linguistics. It begins with a brief introduction to prosody. It then proceeds to describe Miglio, Gries, & Harris (2014), a comparison of prosodic coding of new information by bilingual Spanish-English speakers and monolingual Spanish speakers. A description of Harris & Gries (2011) follows. This study compares the vowel duration variability of bilingual Spanish-English speakers and monolingual Spanish speakers, and touches upon corpus-based frequency effects and differences in linguistic aptitude between the two speaker groups. Finally, a portion of anongoing study is described (Harris in preparation). This section describes the use of prosodic variables and ensemble methods (or methods that use multiple learning algorithms) to classify languages, even in the case of impoverished data. All three experiments have implications and applications to the field of forensic linguistics, which are touched upon in each respective section and discussed in a more in-depth manner in the final section of this article. Furthermore, the applications of these methods to forensic linguistics are discussed in light of best practices for forensic linguistics, as outlined in Chaski (2013).

Most motile bacteria sense and respond to their environment through a transmembrane chemoreceptor array whose structure and function have been well-studied, but many species also contain an additional cluster of chemoreceptors in their cytoplasm. Although the cytoplasmic cluster is essential for normal chemotaxis in some organisms, its structure and function remain unknown. Here we use electron cryotomography to image the cytoplasmic chemoreceptor cluster in Rhodobacter sphaeroides and Vibrio cholerae. We show that just like transmembrane arrays, cytoplasmic clusters contain trimers-of-receptor-dimers organized in 12-nm hexagonal arrays. In contrast to transmembrane arrays, however, cytoplasmic clusters comprise two CheA/CheW baseplates sandwiching two opposed receptor arrays. We further show that cytoplasmic fragments of normally transmembrane E. coli chemoreceptors form similar sandwiched structures in the presence of molecular crowding agents. Together these results suggest that the 12-nm hexagonal architecture is fundamentally important and that sandwiching and crowding can replace the stabilizing effect of the membrane. DOI: http://dx.doi.org/10.7554/eLife.02151.001, eLife digest Many bacteria swim through water by rotating tiny hair-like structures called flagella. In E. coli, if all the flagella on the surface of a bacterium rotate in a counterclockwise fashion, then it will swim in a particular direction, but if the flagella all rotate in an clockwise fashion, then the bacterium will stop swimming and start to tumble. Bacteria use a combination of swimming and tumbling in order to move towards or away from certain chemicals. For example, a bacterium is able to move towards a source of nutrients because it is constantly evaluating its environment and will swim forward for longer periods of time when it recognizes the concentration of the nutrient is increasing. And if it senses that the nutrient concentration is decreasing, it will tumble in an effort to move in a different direction. Many bacteria, such as E. coli, rely on proteins in their cell membrane called chemoreceptors to sense specific chemicals and then send signals that tell the flagella how to rotate. These transmembrane receptors and their role in chemotaxis—that is, movement towards or away from specific chemicals in the environment—have been widely studied. However, other bacteria also have chemoreceptors in the cytoplasm inside the bacterial cell, and much less is known about these. Now, Briegel et al. have examined the cytoplasmic chemoreceptors of two unrelated bacteria, R. sphaeroides and V. cholera, and found that the cytoplasmic chemoreceptors arrange themselves in hexagonal arrays, similar to the way that transmembrane chemoreceptors are arranged. However, the cytoplasmic chemoreceptors arrange themselves in a two-layer sandwich-like structure, whereas the transmembrane chemoreceptors are arranged in just one layer. The next step is to understand how chemical binding causes these arrays to send their signals to the motor. A complete understanding of this signaling system may ultimately allow scientists to re-engineer it to draw bacteria to targets of medical or environmental interest, such as cancer cells or contaminated soils. DOI: http://dx.doi.org/10.7554/eLife.02151.002

We have obtained spectra of the Galactic center at energies 400-600 keV from high-resolution data acquired by the TGRS Ge spectrometer on board the WIND mission during 1995-1997. The data were obtained using an on-board occulter, and are relatively free from systematics and backgrounds. Analysis of the spectra reveals a well-resolved electron-positron annihilation line at 511 keV and the associated continuum due to annihilation via positronium formation. Measurements of the line width and the line-to-continuum ratio allow some constraints to be placed on the interstellar sites where annihilation occurs.

We have searched over 9 yr of data from the Solar Maximum Mission (SMM) Gamma Ray Spectrometer for gamma-ray bursts (GRBs) with abnormally hard spectra that may have been missed in previous searches in the 0.35-0.8 MeV energy band. For this purpose, we searched the higher 0.8-10 MeV band. We have found only two new GRBs in this search, compared to 177 GRBs found in the 0.35-0.8 MeV band. We have made a careful examination of the threshold conditions for identifying the 0.8-10 MeV events, which confirms that there is no undiscovered population of hard-spectrum GRBs that have escaped detection by SMM, BATSE, and other instruments triggered by low-energy γ-ray emission. This conclusion does not apply to GRBs with duration less than 2 s, nor to those that are much fainter than the general population. Our results constrain models of GRBs that require or allow the peak in energy emission to be above 1 MeV.

Bacterial chemoreceptors cluster in highly ordered, cooperative, extended arrays with a conserved architecture, but the principles that govern array assembly remain unclear. Here we show images of cellular arrays as well as selected chemoreceptor complexes reconstituted in vitro that reveal new principles of array structure and assembly. First, in every case, receptors clustered in a trimers-of-dimers configuration, suggesting this is a highly favored fundamental building block. Second, these trimers-of-receptor dimers exhibited great versatility in the kinds of contacts they formed with each other and with other components of the signaling pathway, although only one architectural type occurred in native arrays. Third, the membrane, while it likely accelerates the formation of arrays, was neither necessary nor sufficient for lattice formation. Molecular crowding substituted for the stabilizing effect of the membrane and allowed cytoplasmic receptor fragments to form sandwiched lattices that strongly resemble the cytoplasmic chemoreceptor arrays found in some bacterial species. Finally, the effective determinant of array structure seemed to be CheA and CheW, which formed a “superlattice” of alternating CheA-filled and CheA-empty rings that linked receptor trimers-of-dimer units into their native hexagonal lattice. While concomitant overexpression of receptors, CheA, and CheW yielded arrays with native spacing, the CheA occupancy was lower and less ordered, suggesting that temporal and spatial coordination of gene expression driven by a single transcription factor may be vital for full order, or that array overgrowth may trigger a disassembly process. The results described here provide new insights into the assembly intermediates and assembly mechanism of this massive macromolecular complex.

Bispecific antibodies that retarget cytotoxic T cell activity to kill cancer cells are currently under clinical evaluation. However, the molecular mechanism for how CD3-bispecific antibodies 'trigger' intracellular T cell signaling is not known. We demonstrate that bispecific antibodies invoke an equivalent biophysical mechanism of TCR triggering as that observed for the TCR/pMHC interaction, including target clustering and exclusion of CD45 phosphatase from the synapse. The dimensions of the target molecule play a key role in the efficiency of the synapse formation. However, we demonstrate that rational epitope selection can overcome the spatial inhibition caused by target molecules with a large extracellular domain and result in efficient synapse formation and highly potent T cell triggering. With this insight, we developed a novel T-cell dependent bispecific (TDB) antibody, anti-FcRH5/CD3 TDB, targeting the B cell lineage marker FcRH5 for multiple myeloma. Anti-FcRH5/CD3 TDB demonstrated cytotoxicity against human plasma cells and patient derived myeloma tumor cells at picomolar doses. Very low target expression level is sufficient to induce anti-FcRH5/CD3 TDB mediated killing, indicating broad activity in multiple myeloma where the prevalence of FcRH5 expression is 100%. In primates, anti-FcRH5/CD3 treatment resulted in complete depletion of tissue B cells and bone marrow plasma cells. Anti-FcRH5/CD3 TDB induces immunosuppressive feedback signaling, including PD1 up-regulation, which can be overcome by PD-L1 antibodies. These data demonstrate the potential for the anti-FcRH5/CD3 TDB, alone or in combination with inhibition of PD1/PDL1 signaling in the treatment of multiple myeloma and other B-cell malignancies. Disclosures Li: Genentech: Employment. Stagg:Genentech: Employment. Johnston:Genentech: Employment. DiCara:Genentech: Employment. Clark:Genentech: Employment. Cook:Genentech: Employment. Slaga:Genentech: Employment. Nakamura:Genentech: Employment. Luke:Genentech: Employment. Sukumaran:Genentech: Employment. Luis:Genentech: Employment. Ye:Genentech: Employment. Sumiyoshi:Genentech: Employment. Danilenko:Genentech: Employment. Lee:Genentech: Employment. Totpal:Genentech: Employment. Ellerman:Genentech: Employment. Hötzel:Genentech: Employment. Junttila:Genentech: Employment.

Modern solid-state NMR methods can acquire high-resolution protein spectra for structure determination. However, these methods use rapid sample spinning and intense decoupling fields that can heat and denature the protein being studied. Here we present a strategy to avoid destroying valuable samples. We advocate first creating a sacrificial sample, which contains unlabeled protein (or no protein) in buffer conditions similar to the intended sample. This sample is then doped with the chemical shift thermometer Sm2Sn2O7. We introduce a pulse scheme called TCUP (for Temperature Calibration Under Pulseload) that can characterize the heating of this sacrificial sample rapidly, under a variety of experimental conditions, and with high temporal resolution. Sample heating is discussed with respect to different instrumental variables such as spinning speed, decoupling strength and duration, and cooling gas flow rate. The effects of different sample preparation variables are also discussed, including ionic strength, the inclusion of cryoprotectants, and the physical state of the sample (i.e. liquid, solid, or slurry). Lastly, we discuss probe detuning as a measure of sample thawing that does not require retuning the probe or using chemical shift thermometer compounds. Use of detuning tests and chemical shift thermometers with representative sample conditions makes it possible to maximize the efficiency of the NMR experiment while retaining a functional sample.

Large-diameter metal-on-metal articulations reportedly provide better stability and range of motion than smaller diameter bearings. We therefore asked whether a large-diameter (44- to 50-mm) metal-on-metal articulation (Durom) would eliminate dislocation and provide similar functional scores and clinical and radiographic failure rates as those with 28-mm articulation. We prospectively followed 181 patients (207 hips) who had a large-diameter articulation implanted between May 2006 and November 2007. We compared these patients with a historical control of 54 patients who had a small-diameter (28-mm Metasul) articulation. All patients had a Harris hip score and a self-assessment of outcome and radiographic followup. The minimum followup was 1 year (mean, 1.6 years; range, 1-2 years). During the followup period, we performed revisions on 29 patients (30 hips [15%]) with 21 of 29 (72%) having radiographic criteria of loosening. Thirteen retrieved cups and acetabular tissue were examined histologically. Twenty-eight of 151 unrevised patients had radiographic impending failure; 12 without revision had clinical failure. Eight patients (nine hips) had both clinical failure and impending radiographic failure. Cup inclination was 41.3 degrees +/- 5.4 degrees and anteversion was 20.2 degrees +/- 7 degrees. The revision rate and quality of clinical results were unacceptable as compared with our historical controls. We do not recommend use of the Durom implant.Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Problem Falls represent a significant occupational hazard, particularly in industries with dynamic work environments. This paper describes rates of noncompliance with fall hazard prevention requirements, perceived safety climate and worker knowledge and beliefs, and the association between fall exposure and safety climate measures in commercial aircraft maintenance activities. Methods Walkthrough observations were conducted on aircraft mechanics at two participating facilities (Sites A and B) to ascertain the degree of noncompliance. Mechanics at each site completed questionnaires concerning fall hazard knowledge, personal safety beliefs, and safety climate. Questionnaire results were summarized into safety climate and belief scores by workgroup and site. Noncompliance rates observed during walkthroughs were compared to the climate-belief scores, and were expected to be inversely associated. Results Important differences were seen in fall safety performance between the sites. The study provided a characterization of aircraft maintenance fall hazards, and also demonstrated the effectiveness of an objective hazard assessment methodology. Noncompliance varied by height, equipment used, location of work on the aircraft, shift, and by safety system. Discussion Although the expected relationship between safety climate and noncompliance was seen for site-average climate scores, workgroups with higher safety climate scores had greater observed noncompliance within Site A. Overall, use of engineered safety systems had a significant impact on working safely, while safety beliefs and climate also contributed, though inconsistently. Impact on Industry The results of this study indicate that safety systems are very important in reducing noncompliance with fall protection requirements in aircraft maintenance facilities. Site-level fall safety compliance was found to be related to safety climate, although an unexpected relationship between compliance and safety climate was seen at the workgroup level within site. Finally, observed fall safety compliance was found to differ from self-reported compliance.

A new generation of Ge-based high-resolution gamma-ray spectrometers has allowed accurate measurements to be made of the profiles, widths and energies of the gamma-ray lines emitted in the impulsive phases of solar flares. Here we present measurements in two flares of the energies of the de-excitation lines of 12C and 16O at 4.4 and 6.1 MeV respectively by the Ge spectrometer SPI on board INTEGRAL, from which Doppler shifts are derived and compared with those expected from the recoil of 12C and 16O nuclei which were excited by the impacts of flare-accelerated ions. An anomalous Doppler measurement (in terms of recoil theory) has been reported by the Ge spectrometer RHESSI in a flare near the east limb, and explained by a tilt of the magnetic field lines at the footpoint of a magnetic loop away from the vertical, and towards the observer. This might be interpreted to imply a significant difference between the Doppler shifts on the east and west limbs, if it is a general phenomenon. SPI observed both east and west limb flares and found no significant difference in Doppler shifts. We also measured the shapes and fluences of these lines, and their fluence ratio to the 2.2 MeV line from the capture of flare-generated neutrons. Analyses of both quantities using thick-target models parametrized by solar physical and geometric quantities suggest that the two flares studied here also have magnetic fields tilted towards the observer, though the significance of the measurements is not high., 9 pp., 7 figs., accepted by A&A

Intense and complex instrumental backgrounds, against which the much smaller signals from celestial sources have to be discerned, are a notorious problem for low and intermediate energy gamma-ray astronomy (~50 keV - 10 MeV). Therefore a detailed qualitative and quantitative understanding of instrumental line and continuum backgrounds is crucial for most stages of gamma-ray astronomy missions, ranging from the design and development of new instrumentation through performance prediction to data reduction. We have developed MGGPOD, a user-friendly suite of Monte Carlo codes built around the widely used GEANT (Version 3.21) package, to simulate ab initio the physical processes relevant for the production of instrumental backgrounds. These include the build-up and delayed decay of radioactive isotopes as well as the prompt de-excitation of excited nuclei, both of which give rise to a plethora of instrumental gamma-ray background lines in addition to continuum backgrounds. The MGGPOD package and documentation are publicly available for download from http://sigma-2.cesr.fr/spi/MGGPOD/. We demonstrate the capabilities of the MGGPOD suite by modeling high resolution gamma-ray spectra recorded by the Transient Gamma-Ray Spectrometer (TGRS) on board Wind during 1995. The TGRS is a Ge spectrometer operating in the 40 keV to 8 MeV range. Due to its fine energy resolution, these spectra reveal the complex instrumental background in formidable detail, particularly the many prompt and delayed gamma-ray lines. We evaluate the successes and failures of the MGGPOD package in reproducing TGRS data, and provide identifications for the numerous instrumental lines., Comment: 60 pages, 13 figures, 7 tables, accepted for publication in ApJS

The Solar Maximum Mission satellite's Gamma Ray Spectrometer observed Earth's atmosphere for most of the period 1980-1989. Its 28deg orbit ensured that a range of geomagnetic latitudes (geomagnetic cutoff rigidities) was sampled. We measured the variation with time and rigidity of albedo gamma-ray lines at 1.6 MeV, 2.3 MeV and 4.4 MeV which are diagnostic of Galactic cosmic radiation penetrating the cutoff and of the secondary neutrons produced in the atmosphere. We found that the gamma-ray line intensities varied inversely with solar activity and cutoff rigidity, as expected. The line ratio (1.6 MeV + 2.3 MeV)/4.4 MeV was remarkably constant (close to 0.39) at all times and rigidities; the former two lines are produced by 5-10 MeV secondary neutrons causing excitation and de-excitation of 14N, while the latter is produced by more energetic (>20 MeV) neutrons inducing spallation. We infer that the shape of the secondary neutron energy spectrum is virtually constant everywhere and at all times. We also measured the intensity of the 0.511 MeV electron-positron annihilation line. This line too varies with solar cycle and cutoff rigidity, but its fall-off from low to high rigidity is less marked than that of the nuclear lines. This results from the energy dependences of the cross sections for positron production and for the hadronic processes which which produce secondary neutrons., 11 pages, 12 figs., J. Geophys. Res. in press

The TGRS experiment on board the Wind spacecraft has many advantages as a sky monitor --- broad field of view (~2 pi) centered on the south ecliptic pole), long life (1994-present), and stable low background and continuous coverage due to Wind's high altitude high eccentricity orbit. The Ge detector has sufficient energy resolution (3-4 keV at 511 keV) to resolve a cosmic positron annihilation line from the strong background annihilation line from beta-decays induced by cosmic ray impacts on the instrument, if the cosmic line is Doppler-shifted by this amount. Such lines (blueshifted) are predicted from nucleosynthesis in classical novae. We have searched the entire TGRS database for 1995-1997 for this line, with negative results. In principle such a search could yield an unbiased upper limit on the highly-uncertain Galactic nova rate. We carefully examined the times around the known nova events during this period, also with negative results. The upper limit on the nova line flux in a 6-hr interval is typically, 5 pp. inc. 3 figs. Proc. 5th Compton Symposium (AIP Conf. Series), ed. M. McConnell, in press

Detached broad bean (Vicia faba L.) leaflets were water stressed; within 15 minutes, guard-cell abscisic acid (ABA) concentration increased ninefold. This result eliminates the apparent discrepancy raised by reports of no correlation between initial water-stress effects on stomata and leaf ABA concentration. Six hours after stress relief, guard-cell ABA concentration was near the prestress value, which would seem to implicate other factors in stress aftereffects on stomata.

Thin blood smears of 75 wood storks (Mycteria americana) from Georgia (USA) were made during the summers of 1994–96 and examined for blood parasites. Haemoproteus crnmenium was found in one of 71 juveniles and in two adults from a sample of two subadults and two adults. Intensity of infection in the juvenile and in each of the two adults was 11, 3, and 2 parasites/5,000 erythrocytes, respectively. This is the first record of H. crumenium in the wood stork from Georgia and the second published record of H. crumenium infecting this host in North America. Additionally, one juvenile was infected with a microfilarid.

We have obtained spectra of the Galactic center at energies 400-600 keV from high-resolution data acquired by the TGRS Ge spectrometer on board the WIND mission during 1995-1997. The data were obtained using an on-board occulter, and are relatively free from systematics and backgrounds. Analysis of the spectra reveals a well-resolved electron-positron annihilation line at 511 keV and the associated continuum due to annihilation via positronium formation. Measurements of the line width and the line-to-continuum ratio allow some constraints to be placed on the interstellar sites where annihilation occurs., Comment: 20 pp., 4 figs. Ap. J. Letters in press

Bacterial chemotaxis receptors serve as an ideal model system for elucidating molecular mechanisms of transmembrane signaling, due to the experimental accessibility and established biochemical characterization of these proteins. A gap in the structural understanding of bacterial chemotaxis is present between electron microscopy of the intact arrays of receptor complexes found in cells and high-resolution crystal structures of individual proteins and truncated complexes. To bridge this gap we have initiated multidimensional solid-state NMR spectroscopy studies of a kinase-active ternary complex composed of the soluble 30 kDa cytoplasmic fragment (CF) of the aspartate chemoreceptor, the 70 kDa histidine kinase CheA, and the 18 kDa adaptor protein CheW. We prepared uniformly 13C & 15N labeled CF and obtained both homonuclear and heteronuclear correlation spectra of frozen and unfrozen complexes.The initial data indicates that such experiments are feasible on this functional multi-protein complex. A number of narrow resonances with sub-ppm linewidths are observed in spectra of both frozen and unfrozen samples, and both states exhibit sufficient signal-to-noise for acquiring multidimensional spectra. Overall, the spectra demonstrate the strongly overlapping resonances expected for an alpha-helical 30 kDa protein, which suggests selective labeling for future measurements of structural constraints. For these samples containing uniformly labeled receptor fragment, comparison with predicted chemical shift spectra are being used to test the current structural model. Comparisons of frozen and unfrozen spectra are also being used to assess the presence of static disorder or dynamics in the side chain and backbone resonances. The goal for uniformly labeled receptor samples is to compare spectral properties of both signaling states to gain insight into possible differences in structure and dynamics.This research supported by NIH grant GM085288.

This paper describes a study of the acoustic correlates of speech rhythms of Hispanic Bilinguals living in California and Mexican Monolinguals living in Mexico City in order to study the effect of bilingualism on language, especially on rhythm classes, and the reliability of acoustic correlates in distinguishing these classes. This study addresses stress-timing versus syllable-timing as described in Pike's pioneering work (1945). Ten monolingual speakers from Mexico and ten bilingual Spanish–English speakers born and raised in California to Mexican parents were recorded speaking spontaneously. Fifty vowel durations per speaker were collected from phrases in these recordings and explored statistically and graphically with R.2.12.2 (R Development Core Team, 2011) in order to determine the reliability of various acoustical correlates of language rhythms in differentiating speech rhythms between varieties of Spanish. Specifically the Pairwise Variability Index, introduced by Low and Grabe (1995), and interval...

We have searched for 1980-1988 Solar Maximum Mission gamma-ray spectrometer data for transient emission on timescales from hours to approximately 12 days of broad gamma-ray lines at energies approximately 400 keV, which were reported by the High Energy Astronomy Observatory (HEAO) 1 and SIGMA experiments from two sources lying toward the Galactic center. The lines have been interpreted as the product of the annihilation of positrons in pair plasmas surrounding the black hole candidate 1E 1740.7-2942 and the X-ray binary 1H 1822-371. Our results from a combined exposure of approximately 1.5 x 10(exp 7)s provide no convincing evidence for transient emission of this line on any timescale between approximately 9 hr and approximately 1 yr. Our 3 sigma upper limits on the line flux during approximately 12 day intervals are characteristically 4.8 x 10(exp -3) photon/sq cm/s, while for approximately 1 day intervals our 3 sigma upper limits are characteristically 4.9 x 10(exp -3) photon/sq cm/s. These results imply a duty cycle of less than 1.3% for the transient line measured from 1H 1822-371 during a approximately 3 week interval in 1977 by HEAO 1, and a duty cycle of less than or = 0.8% for the transient line detected in 1990 and 1992 from 1E 1740.7-2942 on approximately 1 day timescales by SIGMA.

We have search spectra obtained by the Solar Maximum Mission Gamma-Ray Spectrometer during 1981-1988 for evidence of transient gamma-ray lines from the Crab Nebula which have been reported by previous experiments at energies 400-460 keV and 539 keV. We find no evidence for significant emission in any of these lines on time scales between aproximately 1 day and approximately 1 yr. Our 3 sigma upper limits on the transient flux during 1 d intervals are approximately equal to 2.2 x 10(exp -3) photons/sq cm/s for narrow lines at any energy, and approximately equal to 2.9 x 10(exp -3) photons/sq cm/s for the 539 keV line if it is as broad as 42 keV Full Width at Half Maximum (FWHM). We also searched our data during the approximately 5 hr period on 1981 June 6 during which Owens, Myers, & Thompson (1985) reported a strong line at 405 keV. We detected no line down to a 3 upper sigma limit of 3.3 x 10(exp -3) photons/sq cm/s in disagreement with the flux 7.2 +/- 2.1 x 10(exp -3) photos/sq cm/s measured by Owens et al.

Free neutrons produced by nuclear reactions in high-temperature plasmas may undergo proton capture in ambient material, giving rise to gamma-ray emisison in a line at 2.223 MeV. Plausible settings for this process include accretion disks around black holes, material accreting onto neutron stars, and the binary companions of TeV gamma-ray sources. Data accumulated by the Solar Maximum Mission Gamma Ray Spectrometer (GRS) between 1980 and 1989 have been searched for evidence of this line, during periods when the black hole candidates Cygnus X-1 and the Galactic center were in transit across the GRS aperture. During these periods the neutron-star X-ray binaries Cygnus X-3 and Scorpius X-1 were also in the respective GRS fields of view. A 3-sigma upper limit of 0.0001/sq cm s has been placed on the steady emission in the 2.223 MeV line from the Galactic center and Scorpius X-1. Upper limits in the range 0.00012-0.00022 gamma/sq cm s have been set for Cygnus X-1 according to different models of the origin of the emission. The 3-sigma upper limit to the phase-averaged steady emission from Cygnus X-3 was found to be 0.00012 gamma/sq cm s.

Unstable Be-7 (half-life 53.28 days) is expected to be present in the ejecta of classical novae. If the frequency of novae in the central Galaxy is high enough, a nearly steady state abundance of Be-7 will be present there. Data accumulated during transits of the Galactic center across the aperture of the Solar Maximum Mission Gamma Ray Spectrometer have been searched for evidence of the 478 keV gamma-ray line resulting from Be-7 decay. A 3-sigma upper limit of 0.00016 gamma/sq cm s has been placed on the emission in this line from the central radian of the Galactic plane. Less stringent limits have been set on the production of Be-7 in Nova Aquilae 1982, Nova Vulpeculae 1984 No. 2, and Nova Centauri 1986 from observations with the same instrument.

The low-energy gamma-ray spectrum from the direction of the Galactic center is determined using data obtained with the SMM Gamma-Ray Spectrometer. It is found that the diffuse gamma-ray spectrum from the Galactic center region can be interpreted in a straightforward way as the sum of five components of a presented equation. The components include a hard power law dominating the continuum at high energies caused principally by cosmic ray electron bremsstrahlung radiation, two narrow lines due to Al-26 decay and positron annihilation, an excess continuum component below 0.511 MeV consistent with the annihilation of positrons by formation of Ps, and a soft power law at low energies which is consistent with an extrapolation upward in energy of known hard X-ray sources in the Galactic center region. 59 refs.

The contents of (+)-cis-abscisic acid (ABA) and alkaline-hydrolyzable ABA-conjugate(s) were analyzed by means of enzyme immunoassay in partially purified extracts of developing and mature sweet orange fruit (Citrus sinensis [L.] Osbeck cv Washington navel). A relatively small increase in ABA was observed in the fruit exocarp during the natural color transition from green to orange. At the same time, the ABA-conjugate level increased approximately 12-fold in this tissue. The contents of ABA and ABA-conjugate equaled 15.0 ± 0.7 and 107.8 ± 2.1 nanomoles per gram fresh weight, respectively, in the exocarp at harvest. Other tissues also contained considerable quantities of these compounds. Whereas the highest ABA content was observed in the exocarp, the highest ABA-conjugate content was observed in the central vascular axis of the fruit and equaled 187.0 ± 10.3 nanomoles per gram fresh weight. The only immunoreactive conjugate found in significant quantity in mature fruit was identified as abscisyl-β-d-glucopyranoside (ABA-GE) based on (a) immunological cross-reactivity, (b) thin layer chromatography co-chromatography with authentic standards in two solvent systems, (c) susceptibility to both chemical and enzymic degradation, and (d) mass spectroscopy.

Mesures des abondances de 12 C, 13 C et 18 O dans la photosphere solaire a partir de plus de 900 raies des bandes fondamentales de vibration des especes CO substituees isotopiquement