cssi/SciSciGPT-SciSciNet huggingface dataset:
The Inhibition of Rat Adrenal Cytochrome P-45011β Gene Expression by Androgens

The synthetic androgen methylandrostenediol (MAD) and the naturally occurring one, testosterone, both bring about hypertensive cardiovascular disease when chronically administered to rats. The pathogenesis of this form of experimental hypertension is thought to result from inhibition of steroid 11β-hydroxylase activity. In contrast to the above androgens, 19–nortestosterone, androstenedione and dehydroepiandrosterone (DHEA) have been reported to be without effect in elevating blood pressure. To examine the mechanism(s) involved, we have in this study compared the effects of a number of androgens on adrenal cytochrome P- 45011β enzyme and mRNA steady state levels. These parameters were also correlated with the ability of adrenal mitochondria isolated from these groups to hydroxylate 11–deoxycorticosterone (DOC) to corticosterone and 18–hydroxy-11–deoxycorticosterone (18–hydroxy-DOC). Rats treated for seven days with 10 mg per day of dihydrotestosterone, testosterone, 19–nortestosterone or MAD showed a prof...
Radiation-induced coronary artery disease

Excessive unprotected radiation to the heart appears to lead to the development of CAD, even in the absence of significant cardiovascular risk factors. The coexistence of such factors may enhance the probability of CAD. The presence of hypercholesterolemia and concomitant or sequential use of chemotherapeutic agents (especially doxorubicin) could further increase this risk. Therapeutic decisions, as with any other manifestation of CAD, relate to the extent of myocardium at jeopardy and to the overall diffuseness of CAD. Management options possible are PTCA or coronary artery bypass surgery. The latter may be required in left main artery stenosis and complicated ostial lesions. Use of shielding should decrease the associated risk of radiation-induced CAD in future years. However, clinicians should continue to have a high degree of suspicion of CAD in patients treated with thoracic radiation without cardiac shielding.
ON SOME TANTALUM ABUNDANCES IN METEORITES AND TEKTITES

Abstract Tantalum abundances, or upper abundance limits, have been determined by neutron activation analysis in 10 chondrite specimens, 3 achondrites, 3 siderites, 1 specimen of meteoritic olivine, 1 specimen of meteoritic troilite, 4 tektites, 1 impact glass, 1 soil specimen from a tektite occurrence, and 1 deep-sea sediment. The chondritic tantalum abundance of 0.021 ppm found in this work is in good agreement with the value of 0.023 obtained by Atkins and Smales (1960). The similarity of tantalum abundances in tektites to those in common terrestrial materials is noted.
INTRACORONARY CARDIOSPHERE-DERIVED CELLS AFTER MYOCARDIAL INFARCTION: MAGNETIC RESONANCE IMAGING ANALYSIS OF REGENERATION AND DETERMINANTS OF EFFICACY IN THE FINAL 1-YEAR RESULTS OF THE CADUCEUS TRIAL

Cardiosphere-derived cells (CDCs) exert regenerative effects in post-MI patients with LV dysfunction in the CADUCEUS trial. Here we report full 1-year results and correlates of efficacy. Autologous CDCs (12.5-25×106) grown from endomyocardial biopsies were infused into the infarct-related artery
Plant regeneration from indica rice (Oryza sativa L.) protoplasts.

Rice (Oryza sativa L.) plants of the indica cultivar IR54 were regenerated from protoplasts. Conditions were developed for isolating and purifying protoplasts from suspension cultures with protoplast yields ranging from 1·106 to 15·106 viable protoplasts/1 g fresh weight. Protoplast viability after purification was generally over 90%. Protoplasts were cultured in a slightly modified Kao medium in a Petri plate by placing them onto a Millipore filter positioned on top of a feeder (nurse) culture containing cells from a suspension culture of the japonica rice, Calrose 76. Plating efficiencies of protoplasts ranged from 0.5 to 3.0%; it was zero in the absence of the nurse culture. Protoplast preparations usually contained no contaminating cells, and when present, the number of cells never exceeded 0.1% of the protoplasts. After three weeks the Millipore filter with callus colonies were transferred off feeder cells and onto a Linsmaier and Skoog-type medium for an additional three weeks. Selected callus colonies that had embryo-like structures were then transferred to regeneration medium containing cytokinins, and regeneration frequencies up to 80% were obtained. Small shoots emerged and were transferred to jars for root development prior to transferring to pots of soil and growing the plants to maturity in growth chambers. Of the cytokinins evaluated, N6-benzylaminopurine was the most effective in promoting shoot formation; however, kinetin was also somewhat effective. Regeneration medium could be either an N6 or Murashige and Skoog basal medium. Of 76 plants grown to maturity, 62 were fertile, and the plant heights averaged about three-fourths the height of seed-grown plants. Two other suspension cultures of IR54, one developed from the protoplast callus of the initial IR54 line, and the other developed from callus produced by mature seeds, have yielded protoplasts capable of regenerating plants when using cells of the Calrose 76 suspension as a nurse culture. In addition, protoplasts obtained from three-week-old primary callus of immature embryos of IR54 were capable of regenerating plants when using the same culture conditions.
Propagation of waves along an impedance boundary

A theoretical analysis of the scalar wave field due to a point source above a plane impedance boundary is presented. A surface wave is found to be an essential component of the total wave field. It is shown that, as a result of ducting of energy by the surface wave, the amplitude of the total wave near the boundary can be greater than it would be if the boundary were perfectly reflecting. Asymptotic results, valid near the boundary, are obtained both for the case of finite impedance (the soft-boundary case) and for the limiting case in which the impedance becomes infinite (the hard-boundary case). In the latter, the wave amplitude in the farfield decreases essentially inversely as the horizontal propagation distance; in the former (if the surface-wave term is neglected), it decreases inversely as the square of the horizontal propagation distance.
The DNA Damage Checkpoint in Embryonic Cell Cycles Is Dependent on the DNA-to-Cytoplasmic Ratio

Abstract In Xenopus , cell cycle checkpoints monitoring DNA damage, DNA replication, and spindle assembly do not appear until after the midblastula transition (MBT; 4000 cells). We show that a DNA damage checkpoint can slow the cell cycle even in 2-cell embryos when the DNA content is increased. Slowing follows caffeine-sensitive activation of the checkpoint kinase, Chk1; degradation of the cell cycle phosphatase, Cdc25A; and inhibitory phosphorylation of Cdc25C and cyclin-dependent kinases (Cdks). Alterations in the DNA-to-cytoplasmic ratio elicit a dose-dependent DNA damage checkpoint, and the ratio required to activate Chk1 for the damage response is lower than that associated with "developmental" activation of Chk1 shortly after the MBT. Our results indicate that a maternal damage response, independent of zygotic transcription, is present even in very early embryos, and requires both double-stranded DNA ends and a threshold DNA-to-cytoplasmic ratio to significantly affect the cell cycle.
Right hemisphere reading mechanisms in a global alexic patient

We investigated the implicit, or covert, reading ability of a global alexic patient (EA) to help determine the contribution of the right hemisphere to reading. Previous studies of alexic patients with left hemisphere damage have suggested that the ability to derive meaning from printed words that cannot be read out loud may reflect right hemisphere reading mechanisms. Other investigators have argued that residual left hemisphere abilities are sufficient to account for implicit reading and moreover do not require the postulation of a right hemisphere system that has no role in normal reading processes. However, few studies have assessed covert reading in patients with lesions as extensive as the one in EA, which affected left medial, inferior temporal-occipital cortex, hippocampus, splenium, and dorsal white matter. EA was presented with lexical decision, semantic categorization, phonemic categorization, and letter matching tasks. Although EA was unable to access phonology and could not overtly name words or letters, she was nevertheless capable of making lexical and semantic decisions at above chance levels, with an advantage for concrete versus abstract words. Her oral and written spelling were relatively intact, suggesting that orthographic knowledge is retained, although inaccessible through the visual modality. Based on her ability to access lexical and semantic information without contacting phonological representations, we propose that EA's implicit reading emerges from, and is supported, by the right hemisphere. Finally, we conclude that her spelling and writing abilities are supported by left hemisphere mechanisms.
Damage-Mitigating Control of a Reusable Rocket Engine

This article presents a control concept for damage prediction and damage mitigation in reusable rocket engines for enhancement of structural durability. The key idea here is to achieve high performance without overstraining the mechanical structures so that 1) the functional lives of critical components are increased, resulting in enhanced safety, operational reliability, and availability; and 2) the plant (i.e., the rocket engine) can be inexpensively maintained, and safely and efficiently driven under different operating conditions. To this effect, dynamics of fatigue damage have been modeled in the continuous-time setting instead of the conventional cycle-based approach, and an optimal control policy is formulated by constraining the accumulated damage and its time derivative. Efficacy of the proposed damage mitigation concept is evaluated for life extension of the turbine blades of a bipropellant rocket engine via simulation experiments. The simulation results demonstrate the potential of increasing the structural durability of reusable rocket engines with no significant loss of performance.
Constraints on establishment of plains cottonwood in an urban riparian preserve

Plot sampling and hydraulic modeling were combined to investigate establishment and survival of plains cottonwood along Boulder Creek, an urban stream on the Colorado Plains. We tested the hypothesis that establishment is limited to bare, moist surfaces produced by spring flooding in the current year. No cottonwood germination was observed in 1989 when peak flow was low. A moderate peak of 11.9 m3/s in 1990 resulted in cottonwood establishment on surfaces inundated by discharges less than 15 m3/s. Surviving sapling cottonwoods established before 1989 occurred on surfaces inundated by discharges of 15–31 m3/s and dated to years with peak flows over 15 m3/s. Since 1969, establishment of cottonwood has been limited to a floodplain 21 m wide. Flow regulation and channel stabilization upstream and downstream of the study area have reduced the channel movement and overbank flooding that otherwise would have created bare, moist sites suitable for cottonwood establishment across a wider area. GIS analysis of aerial photographs shows that between 1937 and 1992 the channel has not moved and forest has encroached upon formerly open areas near the channel. A terrace, 317 m wide, is now dominated by trees that can reproduce in the absence of disturbance, especially the exotic crack willow.
Solar optical processing

Abstract We will show that a white-light processor can be easily implemented with natural solar light for optical signal processing. The basic advantage of the solar optical processing is that the processing system does not require to carry an artificial light source, which is very suitable for spaceborne optical processing application. In addition to the simplicity, versatility, polychromaticity, and noise immunity of the white-light processing system, the solar processor is very durable and the operation is very cost effective. Several elementary experimental demonstrations obtained with the solar light processing are given.
Constraint on Lorentz non-invariance from the Michel parameter

Abstract It is pointed out that the Michel parameter can be used to put a limit on a class of Lorentz non-invariant interactions.
Protein secretion: Getting folded proteins across membranes

Work on metalloprotein export in bacteria, and protein import into chloroplasts, has converged in the recognition of a novel membrane translocation system with two fascinating properties: it is driven energetically by the transmembrane pH gradient, and it is capable of translocating folded proteins.
PAH dissipation in spiked soil : Impacts of bioavailability, microbial activity, and trees

While trees have demonstrated potential in phytoremediation of several organic contaminants, little is known regarding their ability to impact the common soil contaminant PAHs. Several species of native North American trees were planted in soil artificially contaminated with three PAHs. Plant biomass, PAH dissipation, and microbial mineralization were monitored over the course of one year and environmental conditions were allowed to follow typical seasonal patterns. PAH dissipation and mineralization were not affected by planting. Extensive and rapid loss of PAHs was observed and attributed to high bioavailability and microbial activity in all treatments. The rate of this loss may have masked any significant planting effects. Anthracene was found to be more recalcitrant than pyrene or phenanthrene. Parallel soil aging studies indicated that sequestration to soil components was minimal. Contrary to common inferences in literature, amendment with decaying fine roots inhibited PAH degradation by the soil microbial community. Seasonal variation in environmental factors and rhizosphere dynamics may have also reduced or negated the effect of planting and should be taken into account in future phytoremediation trials. The unique root traits of trees may pose a challenge to traditional thought regarding PAH dissipation in the rhizosphere of plants.
Comparison of plasma corticosterone- and progesterone-binding activity in rat and human

Corticosterone-and progesterone-binding activity were measured by saturation analysis, with dextran-charcoal separation, in plasma obtained from male and female rats, and a normal male and female human. In plasma from normal male and female rats, progesterone was much less effective than corticosterone in displacing 3H-corticosterone from plasma protein binding sites although the parallelism of the displacement curves indicated competition for the same binding sites. In plasma from the normal male human, corticosterone and progesterone were equally effective in displacing 3H-corticosterone. However, 3H-progesterone showed no apparent binding to either rat or human plasma proteins, suggesting that dextran-charcoal effectively removed progesterone from transcortin binding sites at 4°C. This observation was confirmed by multiple equilibrium dialysis. In dialysis, 3H-corticosterone and 3H3-progesterone were bound equally by human plasma, but rat plasma bound 3H-corticosterone to a much greater extent than it did 3H-progesterone. These data indicate that, in contrast to human plasma, rat plasma has much greater affinity for corticosterone than for progesterone.
I made It Because of Me: Beliefs About the Causes of Wealth and Poverty

Using probability data collected from a sample of metropolitan residents, variation in beliefs about the “causes” of wealth and poverty was examined. It was found that respondents generally preferred individualistic explanations of wealth and poverty over structural ones. By comparing results from this study with those from other studies, it was concluded that many stratification beliefs are remarkably similar across locations and stable over time. Income was strongly correlated with the odds of favoring individualistic beliefs over structural ones. Strong correlations were also found between individualistic beliefs and the likelihood of perceiving inequalities as fair and not extensive. And finally, a significant link was observed between individualistic beliefs and perceiving the world as a just place where hard work is tied to success. Discussion and implications are also provided.
Selenoprotein K form an intermolecular diselenide bond with unusually high redox potential

Selenoprotein K (SelK) is a membrane protein involved in antioxidant defense, calcium regulation and the ER-associated protein degradation pathway. We found that SelK exhibits a peroxidase activity with a rate that is low but within the range of other peroxidases. Notably, SelK reduced hydrophobic substrates, such as phospholipid hydroperoxides, which damage membranes. Thus, SelK might be involved in membrane repair or related pathways. SelK was also found to contain a diselenide bond—the first intramolecular bond of that kind reported for a selenoprotein. The redox potential of SelK was −257 mV, significantly higher than that of diselenide bonds in small molecules or proteins. Consequently, SelK can be reduced by thioredoxin reductase. These finding are essential for understanding SelK activity and function.
The mass of the muon

Abstract It is shown that a classical relativistic charged particle has an anomalous magnetic moment g=4α/3. If such a “dressed” particle with its mass m, charge e, and anomalous magnetic moment g is quantized by a generalized Dirac equation, then the wave equation predicts a second mass mμ=me(3/2α+1). It is suggested that a magnetic portion of the self-energy is quantized.
MAP Kinase Translocates into the Nucleus of the Presynaptic Cell and Is Required for Long-Term Facilitation in Aplysia

Long-term facilitation of the sensory to motor synapse in Aplysia requires gene expression. While some transcription factors involved in long-term facilitation are phosphorylated by PKA, others lack PKA sites but contain MAP Kinase (MAPK) phosphorylation sites. We now show that MAPK translocates into the nucleus of the presynaptic but not the postsynaptic cell during 5-HT-induced long-term facilitation. The presynaptic nuclear translocation of MAPK is also triggered by elevations in intracellular cAMP. Injection of anti-MAPK antibodies or of MAPK Kinase inhibitors into the presynaptic cell blocks long-term facilitation, without affecting basal synaptic transmission or short-term facilitation. Thus, MAPK appears to be specifically recruited and necessary for the long-term form of facilitation. This mechanism for long-term plasticity may be quite general: cAMP also activated MAPK in mouse hippocampal neurons, suggesting that MAPK may play a role in hippocampal long-term potentiation.
Organic chemistry: Molecular cross-talk

There is a long way to go before artificial enzymes can reproduce the functions of the real things. The advent of systems that generate and respond to signals may bring that ideal a step closer.
Characterizing the resistance generated by a molecular bond as it is forcibly separated

The goal of measurements of the resisting force generated by a molecular bond as it is being forcibly separated under controlled conditions is to determine functional characteristics of the bond. Here, we establish the dependence of force history during unbinding on both those parameters chosen to characterize the bond itself and the controllable loading parameters. This is pursued for the practical range of behavior in which unbinding occurs diffusively rather than ballistically, building on the classic work of Kramers. For a bond represented by a one-dimensional energy landscape, modified by a second time-dependent energy profile representing applied loading, we present a mathematical analysis showing the dependence of the resistance of the bond-on-bond well shape, general time dependence of the imposed loading, and stiffness of the loading apparatus. The quality of the result is established through comparison with full numerical solutions of the underlying Smoluchowski equation.
Coincidence theory for spaces which fiber over a nilmanifold

Let be a finite connected complex and a fibration over a compact nilmanifold . For any finite complex and maps , we show that the Nielsen coincidence number vanishes if the Reidemeister coincidence number is infinite. If, in addition, is a compact manifold and is the constant map at a point , then is deformable to a map such that .
Three Years Later: Culture in Psychology—Between Social Positioning and Producing New Knowledge:

Since the previous editorial analysis (Valsiner, 2001) the journal has continued as an intellectually exciting forum for international and creative scholarship. For further development of the field...
Optical studies of UHURU sources. VI. The identification of the optical counterpart of 2U 0115-73=SMC X-1

A study of the stars in and near the error box for XMC X-1=2U 0115-73 has revealed that Sandulesk No. l60, a BO supergiant located on the southeast edge of the Small Magellanic Cloud, shows small light varations which go through a double cycle with a period equal to that of the X-ray binary. (auth)
The in vitro metabolism of 2,4-dinitrophenol by rat liver homogenates.

Abstract The in vitro metabolism of 14C-2-4-dinitrophenol (DNP, 10−4 m ) was examined in rat liver (300–500 g males); DNP, 4-amino-2-nitrophenol (4A2NP) and 2-amino-4-nitrophenol (2A4NP) were separated. The extraction procedure for metabolite separation was developed on the basis of pH-dependent aqueous-roganic partitioning. When cofactors and pH were optimized in vitro, the anaerobic enzymatic disappearance of DNP was first order for 30 min. The pH optimum for in vitro disappearance and for metabolite formation was 6.5 (37°C). During a 30-min incubation, 81 ± 4% of DNP was metabolized: 75 ± 4% to 2A4NP, 23 ± 2% to 4A2NP, and 1% to 2,4-diaminophenol. Most enzyme activity was located in the 105,00 g supernatant. Oxygen did not alter the distribution of the enzyme activity, but did decrease metabolite formation after 10 min. It was concluded that in vitro DNP is metabolized by rat liver to 2A4NP and 4A2NP.
Biomolecules in the synthesis and assembly of materials for energy applications

Biomolecules such as RNA, DNA, peptides, and proteins are emerging as powerful chemical tools for the synthesis of inorganic nanoparticles. Specific biomolecule sequences have been isolated that afford remarkable control over the size, shape, polymorph, and hierarchical assembly of nanoparticles. Such exquisite control over nanoparticle growth and integration has already produced materials with unexpected photophysical properties and battery devices with improved performance. Continued exploration of biomolecule-mediated materials synthesis portends further advances in materials for the energy sciences. This review surveys the use of biomolecules in the synthesis and assembly of materials with a primary focus on methods that allow vast landscapes of biomolecule sequence space to be sampled simultaneously to discover unique sequence codes for new materials.
Perovskite to antiperovskite in abf3 compounds

Abstract Results of static energy calculations using ab initio Gordon-Kim potentials for ABF3 perovskites, where A is an alkali metal ion and B is an alkaline earth metal ion, are presented which demonstrate the role of the relative size of A and B in determining the ground state. Our results point out that the antiperovskite structure, obtained by interchanging the positions of A and B, can be viewed as a highly distorted perovskite structure, or vice versa. The energetics of NaCaF3, a predicted ferroelectric, are analyzed in detail.
Adverse events in pregnant women following administration of trivalent inactivated influenza vaccine and live attenuated influenza vaccine in the Vaccine Adverse Event Reporting System, 1990-2009.

Objective The objective of the study was to characterize reports to the Vaccine Adverse Event Reporting System (VAERS) in pregnant women who received seasonal influenza vaccines to assess for potential vaccine safety concerns. Study Design We searched VAERS for reports of adverse events (AEs) in pregnant women who received trivalent inactivated influenza vaccine (TIV) from July 1, 1990 through June 30, 2009, or live attenuated influenza vaccine (LAIV) from July 1, 2003, through June 30, 2009. Results A total of 148 reports after TIV and 27 reports after LAIV were identified. Twenty TIV (13.5%) and 1 LAIV (4%) reports were classified as serious. No specific AEs were reported in 30 TIV (20.3%) and 16 LAIV (59%) reports. The most common pregnancy-specific AE was spontaneous abortion: 17 after TIV (11.5%) and 3 after LAIV (11%). The reporting rate of spontaneous abortion was 1.9 per million pregnant women vaccinated. Conclusion No unusual patterns of pregnancy complications or fetal outcomes were observed in the VAERS reports of pregnant women after the administration of TIV or LAIV.
Structure and temperature dependence of the flexural properties of laboratory freshwater ice sheets

Abstract In this report we present results of small-beam testing conducted in a test tank on ice corresponding in structure to the two major ice types, S-1 and S-2 encountered in lake ice-sheets. Tests of 730 beams in the temperature range −1 to −19°C showed that macrocrystalline (S-1) and columnar (S-2) ice differ appreciably in their flexural characteristics and that these differences are attributable to variations in the size and orientation of the crystals in the ice and the thermal condition of the beams. Parallel testing of cantilever and simply-supported beams indicated a virtual non-dependence of flexural strength on the temperature of the fiber in tension. It was also determined that the sharply terminated corners of conventional cantilever beams are a source of appreciable stress concentration that can reduce the intrinsic flexural strength by as much as one-half but which, in most cases, can be substantially relieved by drilling holes at the beam roots. Overall, flexural strengths did not exceed 1200 kPa for cantilever beams or 1650 kPa for simply-supported beams tested in parallel. The highest flexural strengths were measured on isothermal simply-supported beams of S-2 ice tested with the top surface in tension, with average strengths for such ice increasing from 1650 kPa at −1°C to nearly 2600 kPa at −19°C. Beams made to fail with bottom in tension, tested about 35% weaker due to the greatly increased size of crystals in the bottom of S2 ice sheets. Beams of S1 ice yielded flexural strengths mid-way between those measured on S2 ice. This behavior, which occurs despite the fact that crystal size in S1 ice is always very much larger than in the coarsest-grained S2 ice, is attributed to the dominant vertical c-axis structure of S1 ice that forces tensile failure to propagate in the hard-fail plane of the crystals. It was also determined that temperature gradients in simply-supported beams can decrease flexural strengths by as much as 50% compared to isothermal beams tested at the same ambient air temperatures. Strain-modulus measurements showed little dependence on either the temperature of the beam or its flexural strength, with values ranging from 4–6 GPa for cantilever and parallel simply-supported beams, and from 6–8 GPa for isothermal simply-supported beams.
The energy efficiency of CMP vs. SMT for multimedia workloads

This paper compares the energy efficiency of chip multiprocessing (CMP) and simultaneous multithreading (SMT) on modern out-of-order processors for the increasingly important multimedia applications. Since performance is an important metric for real-time multimedia applications, we compare configurations at equal performance. We perform this comparison for a large number of performance points derived using different processor architectures and frequencies/voltages.We find that for the design space explored, for each workload, at each performance point, CMP is more energy efficient than SMT. The difference is small for two thread systems, but large (18% to 44%) for four thread systems. We also find that the best SMT and the best CMP configuration for a given performance target have different architecture and frequency/voltage. Therefore, their relative energy efficiency depends on a subtle interplay between various factors such as capacitance, voltage, IPC, frequency, and the level of clock gating, as well as workload features. We perform a detailed analysis considering these factors and develop a mathematical model to explain these results.Although CMP shows a clear energy advantage for four-thread (and higher) workloads, it comes at the cost of increased silicon area. We therefore investigate a hybrid solution where a CMP is built out of SMT cores, and find it to be an effective compromise. Finally, we find that we can reduce energy further for CMP with a straightforward application of previously proposed techniques of adaptive architectures and dynamic voltage/frequency scaling.
Organophosphorus Hydrolase Is a Remarkably Stable Enzyme That Unfolds through a Homodimeric Intermediate

Organophosphorus hydrolase (OPH, EC 8.1.3.1) is a homodimeric enzyme that catalyzes the hydrolysis of organophosphorus pesticides and nerve agents. We have analyzed the urea- and guanidinium chloride-induced equilibrium unfolding of OPH as monitored by far-ultraviolet circular dichroism and intrinsic tryptophan fluorescence. These spectral methods, which monitor primarily the disruption of protein secondary structure and tertiary structure, respectively, reveal biphasic unfolding transitions with evidence for an intermediate form of OPH. By investigating the protein concentration dependence of the unfolding curves, it is clear that the second transition involves dissociation of the monomeric polypeptide chains and that the intermediate is clearly dimeric. The dimeric intermediate form of OPH is devoid of enzymatic activity, yet clearly behaves as a partially folded, dimeric protein by gel filtration. Therefore, we propose an unfolding mechanism in which the native dimer converts to an inactive, well-populated dimeric intermediate which finally dissociates and completely unfolds to individual monomeric polypeptides. The denaturant-induced unfolding data are described well by a three-state mechanism with delta G for the interconversion between the native homodimer (N2) and the inactive dimeric intermediate (I2) of 4.3 kcal/mol while the overall standard state stability of the native homodimer relative to the unfolded monomers (2U) is more than 40 kcal/mol. Thus, OPH is a remarkably stable protein that folds through an inactive, dimeric intermediate and will serve as a good model system for investigating the energetics of protein association and folding in a system where we can clearly resolve these two steps.
Diels-alder cyclization of 2,8,10-undecatrienals as a route to 1,2,3,4,4a,5,6,8a-octahydronaphthalenes

Abstract 2,8,10-Undecatrienals have been found to undergo facile Diels-Alder cyclization upon treatment with alkylaluminum chlorides in methylene chloride at low temperature. The reaction is highly endo-selective. Protected alcohol substituents at the C-4 and C-7 positions are fully accommodated and TBDMS protected alcohols show a strong axial preference. The methodology has been applied to a hydronaphthalenecarboxylic add of possible use in a projected total synthesis of the macrocyclic antitumor antibiotic, chlorothricolide.
Regulated translation of listeriolysin O controls virulence of Listeria monocytogenes

Listeria monocytogenes is an intracytosolic bacterial pathogen that escapes from the phagosome using a secreted cytolysin, listeriolysin O (LLO). In the host cytosol, LLO activity is minimized to prevent pore formation in the host plasma membrane; premature lysis of the infected host cell exposes the bacteria to extracellular immune defences of the host and is detrimental to infection. Here we identified nucleotide substitutions in the coding sequence of the LLO gene (hly) that did not alter the protein sequence, yet caused over-production of LLO, cytotoxicity and loss of virulence. These phenotypes were independent of the promoter and, under conditions in which the mutants produced more LLO protein than wild type, levels of hly mRNA were similar. Finally, negative regulation of LLO was maintained even when bacteria were engineered to produce elevated levels of the wild-type hly transcript. Together, our data demonstrate that translational regulation of LLO is critical for L. monocytogenes pathogenesis.
A comparison of syslog and IS-IS for network failure analysis

Accurate reporting and analysis of network failures has historically required instrumentation (e.g., dedicated tracing of routing protocol state) that is rarely available in practice. In previous work, our group has proposed that a combination of common data sources could be substituted instead. In particular, by opportunistically stitching together data from router configuration logs and syslog messages, we demonstrated that a granular picture of network failures could be resolved and verified with human trouble tickets. In this paper, we more fully evaluate the fidelity of this approach, by comparing with high-quality "ground truth" data derived from an analysis of contemporaneous IS-IS routing protocol messages. We identify areas of agreement and disparity between these data sources, as well as potential ways to correct disparities when possible.
The Structural Consequences of Downsizing

This paper examines the impact of downsizing strategy on dimensions and types of organizational structure. Four downsizing strategies are developed to address organization and environment decline. Understanding where and how these strategies modify an organization's activities helps clarity how downsizing impacts organization structure. Propositions are offered that show how downsizing can result in both mechanistic and organic shifts in organization structure. Mechanistic shifts are caused by downsizing strategies that increase the domain of an organization and the structural processes used to support that domain. Organic shifts are caused by downsizing strategies that decrease the domain of an organization and the structural processes used to support that domain. The rationale provided for these shifts offers a strategic explanation for decreases in administrative intensity that lag decreases in organization size. Propositions about the impact of downsizing on organizational structure are offered as a stimulus to further thought and research.
Rewarding creativity: when does it really matter?

This study examined the possibility that the relation between extrinsic rewards (e.g., pay and recognition) and employee creativity varied as a function of two conditions: employee job complexity and employee cognitive style. Our results showed a positive relation between extrinsic rewards and creativity for employees with an adaptive cognitive style who worked on relatively simple jobs. We found a weak relation between rewards and creativity for employees with an innovative cognitive style who worked on complex jobs and a negative relation for those in the adaptive style/complex job and innovative style/simple job conditions. We discussed theoretical and practical implications of these findings.
A finite difference-time domain approach for frequency selective surfaces at oblique incidence

Frequency selective surfaces (FSS) are often analyzed using frequency domain integral equation formulations and the method of moments (MoM) solutions. Because of the required evaluation of periodic Green's functions, and the frequent desire to repeat the analysis at multiple frequencies, these approaches can become computationally intensive. For normal incidence, the finite difference-time domain (FD-TD) provides an alternate approach, since symmetry of the fields permits the use of a periodic side boundary condition, while modeling only a single period of the infinite structure. For the oblique case, where the periodic boundary becomes non-causal, several FD-TD approaches have been proposed. However, these methods all involve either potentially divergent iterative solutions for the time advanced boundary, or phase shifting approaches which limit the excitation to a single frequency. This paper presents an alternative FD-TD approach to the oblique incidence problem. New field quantities are defined related to the electric and magnetic fields through spatially varying time shifts. The FD-TD discretization is then applied to Maxwell's equations rewritten in terms of these new field quantities. This transformation permits the use of an unshifted periodic boundary, and allows the simulation of FSS scattering at oblique incidence for multiple frequencies.
Endomicroscopy imaging of epithelial structures using tissue autofluorescence.

We explore autofluorescence endomicroscopy as a potential tool for real-time visualization of epithelial tissue microstructure and organization in a clinical setting. The design parameters are explored using two experimental systems-an Olympus Medical Systems Corp. stand-alone clinical prototype probe, and a custom built bench-top rigid fiber conduit prototype. Both systems entail ultraviolet excitation at 266 nm and/or 325 nm using compact laser sources. Preliminary results using ex vivo animal and human tissue specimens suggest that this technology can be translated toward in vivo application to address the need for real-time histology.
Programmed cell death and aerenchyma formation in roots

Lysigenous aerenchyma contributes to the ability of plants to tolerate low-oxygen soil environments, by providing an internal aeration system for the transfer of oxygen from the shoot. However, aerenchyma formation requires the death of cells in the root cortex. In maize, hypoxia stimulates ethylene production, which in turn activates a signal transduction pathway involving phosphoinositides and Ca2+. Death occurs in a predictable pattern, is regulated by a hormone (ethylene) and provides an example of programmed cell death.
Fat and carbohydrate balances during adaptation to a high-fat diet

Background: Dietary fat contents are highly variable. Failure to compensate for the positive fat balance that occurs during the shift to a high-fat, low-carbohydrate diet by increasing energy expenditure or by decreasing food intake may result in the gain of fat mass. Objective: The objective of this study was to investigate the time course of fat oxidation during adaptation to an isoenergetic high-fat, low-carbohydrate diet. Design: After a 5-d control diet, dietary fat was increased from 37% of energy to 50% of energy for 4 d in 6 healthy, young lean men. Respiratory quotient and substrate macronutrient oxidation and balance were measured in a respiratory chamber. Fasting concentrations of insulin, glucose, and triacylglycerol; maximal oxygen consumption (VO 2 max) during treadmill exercise; and free-living energy expenditure were determined. Body fat was measured by dual-energy X-ray absorptiometry and visceral adipose tissue by computerized tomography. Results: Compared with the baseline diet, the high-fat, low-carbohydrate diet resulted in positive fat and protein balances and a negative carbohydrate balance. Insulin concentration and the postabsorptive respiratory quotient were positively correlated with the fat balance during the high-fat, low-carbohydrate diet, whereas VO 2 max during treadmill exercise was negatively related to fat balance. With use of stepwise regression, VO 2 max was the best predictor of fat balance. There was a negative correlation between fat balance and carbohydrate balance (r 2 = 0.88). Conclusion: Both baseline insulin concentration and VO 2 max during treadmill exercise predict fat balance during the shift to a high-fat diet under isoenergetic conditions.
Toward an Anarchist Film Theory: Reflections on the Politics of Cinema

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 I. The Politics of Film Theory: From Humanism to Cultural Studies . . . . . . . . . . . . . . 3 II. Foucault and Film Theory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 III. Toward an Anarchist Film Theory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Bibliography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Sympathetic cardiac hyperinnervation and atrial autonomic imbalance in diet-induced obesity promote cardiac arrhythmias.

Obesity increases the risk of arrhythmias and sudden cardiac death, but the mechanisms are unknown. This study tested the hypothesis that obesity-induced cardiac sympathetic outgrowth and hyperinnervation promotes the development of arrhythmic events. Male Sprague-Dawley rats (250–275 g), fed a high-fat diet (33% kcal/fat), diverged into obesity-resistant (OR) and obesity-prone (OP) groups and were compared with rats fed normal chow (13% kcal/fat; CON). In vitro experiments showed that both OR and OP rats exhibited hyperinnervation of the heart and high sympathetic outgrowth compared with CON rats, even though OR rats are not obese. Despite the hyperinnervation and outgrowth, we showed that, in vivo, OR rats were less susceptible to arrhythmic events after an intravenous epinephrine challenge compared with OP rats. On examining total and stimulus-evoked neurotransmitter levels in an ex vivo system, we demonstrate that atrial acetylcholine content and release were attenuated in OP compared with OR and CON groups. OP rats also expressed elevated atrial norepinephrine content, while norepinephrine release was suppressed. These findings suggest that the consumption of a high-fat diet, even in the absence of overt obesity, stimulates sympathetic outgrowth and hyperinnervation of the heart. However, normalized cardiac parasympathetic nervous system control may protect the heart from arrhythmic events.
INTEGRATIVE TESTING OF HOW ENVIRONMENTS FROM THE PAST TO THE PRESENT SHAPE GENETIC STRUCTURE ACROSS LANDSCAPES

Tests of the genetic structure of empirical populations typically focus on the correlative relationships between population connectivity and geographic and/or environmental factors in landscape genetics. However, such tests may overlook or misidentify the impact of candidate factors on genetic structure, especially when connectivity patterns differ between past and present populations because of shifting environmental conditions over time. Here we account for the underlying demographic component of population connectivity associated with a temporarily dynamic landscape in tests of the factors structuring population genetic variation in an Australian lizard, Lerista lineopunctulata, from 24 nuclear loci. Correlative tests did not support significant effect from factors associated with a static contemporary landscape. However, spatially explicit demographic modeling of genetic differentiation shows that changes in environmental conditions (as estimated from paleoclimatic data) and corresponding distributional shifts from the past to present landscape significantly structures genetic variation. Results from model-based inference (i.e., from an integrative modeling approach that generates spatially explicit expectations that are tested with approximate Bayesian computation) contrasts with those from correlative analyses, highlighting the importance of expanding the landscape genetic perspective to tests the links between pattern and process, revealing how factors shape patterns of genetic variation within species.
Plant–fungus mutualism affects spider composition in successional fields

Mutualistic symbionts are widespread in plants and may have strong, bottom-up influences on community structure. Here we show that a grass‐endophyte mutualism shifts the composition of a generalist predator assemblage. In replicated, successional fields we manipulated endophyte infection by Neotyphodium coenophialum in a dominant, non-native plant (Lolium arundinaceum). We compared the magnitude of the endophyte effect with manipulations of thatch biomass, a habitat feature of known importance to spiders. The richness of both spider families and morphospecies was greater in the absence of the endophyte, although total spider abundance was not affected. Thatch removal reduced both spider abundance and richness, and endophyte and thatch effects were largely additive. Spider families differed in responses, with declines in Linyphiidae and Thomisidae due to the endophyte and declines in Lycosidae due to thatch removal. Results demonstrate that the community impacts of non-native plants can depend on plants mutualistic associates, such as fungal endophytes.
Post emergence maturation of the eye of the adult black carpet beetle, Attagenus megatoma (Fab.): An electron microscope study†‡

The black carpet beetle, Attagenus megatoma (Fab.), has been reported to exhibit negative phototaxis immediately after emergence. In later adult life, after the period during which most oviposition has occurred, the beetles are found to be photopositive. The compound eyes of one-day-old (Post-emergence) and nine-day-old (Post-ovipositional) female beetles were studied by electron microscopy and a number of strong differences were found between eyes at the two ages. The corneal facets of one-day eyes had the form of convex-concave lenses, while those of nine-day beetles were double-convex lenses. The primary and secondary pigment cells of young eyes were large and contained much endoplasmic reticulum and little accessory pigment. In the older eyes the pigment cells were reduced and contained much pigment, the proportion of endoplasmic reticulum being greatly reduced by comparison with the one-day eye. The cross-sectional area of the rhabdom was greater in the older eye. The possible relationships between age-related changes in eye morphology and behavioral changes during the same period are discussed.
Activation-Induced Cytidine Deaminase-Dependent DNA Breaks in Class Switch Recombination Occur during G1 Phase of the Cell Cycle and Depend upon Mismatch Repair

Ab class switching occurs by an intrachromosomal recombination and requires generation of double-strand breaks (DSBs) in Ig switch (S) regions. Activation-induced cytidine deaminase (AID) converts cytosines in S regions to uracils, which are excised by uracil DNA glycosylase (UNG). Repair of the resulting abasic sites would yield single-strand breaks (SSBs), but how these SSBs are converted to DSBs is unclear. In mouse splenic B cells, we find that AID-dependent DSBs occur in Sμ mainly in the G 1 phase of the cell cycle, indicating they are not created by replication across SSBs. Also, G 1 phase cells express AID, UNG, and mismatch repair (MMR) proteins and possess UNG activity. We find fewer S region DSBs in MMR-deficient B cells than in wild-type B cells, and still fewer in MMR-deficient/SμTR −/− B cells, where targets for AID are sparse. These DSBs occur predominantly at AID targets. We also show that nucleotide excision repair does not contribute to class switching. Our data support the hypothesis that MMR is required to convert SSBs into DSBs when SSBs on opposite strands are too distal to form DSBs spontaneously.