cssi/SciSciGPT-SciSciNet huggingface dataset:
TNF blockade uncouples toxicity from antitumor efficacy induced with CD40 chemoimmunotherapy.

Agonist CD40 antibodies are under clinical development in combination with chemotherapy as an approach to prime for anti-tumor T cell immunity. However, treatment with anti-CD40 is commonly accompanied by both systemic cytokine release and liver transaminase elevations which together account for the most common dose-limiting toxicities. Moreover, anti-CD40 treatment increases the potential for chemotherapy-induced hepatotoxicity. Here, we report a mechanistic link between cytokine release and hepatotoxicity induced by anti-CD40 when combined with chemotherapy and show that toxicity can be suppressed without impairing therapeutic efficacy. We demonstrate in mice and humans that anti-CD40 triggers transient hepatotoxicity marked by increased serum transaminase levels. In doing so, anti-CD40 sensitizes the liver to drug-induced toxicity. Unexpectedly, this biology is not blocked by depletion of multiple myeloid cell subsets, including macrophages, inflammatory monocytes, and granulocytes. Transcriptional profiling of the liver after anti-CD40 revealed activation of multiple cytokine pathways including TNF and interleukin (IL)-6. Neutralization of TNF, but not IL-6, prevented sensitization of the liver to hepatotoxicity induced with anti-CD40 in combination with chemotherapy without impacting anti-tumor efficacy. Our findings reveal a clinically feasible approach to mitigate toxicity without impairing efficacy in the use of agonist CD40 antibodies for cancer immunotherapy.
Fine-Grained Analysis of the Use of Neutral and Controversial Terms for COVID-19 on Social Media

During the COVID-19 pandemic, ‘Chinese Virus’ emerged as a controversial term for coronavirus. To some, it may seem like a neutral term referring to the physical origin of the virus. To many others, however, the term is in fact attaching ethnicity to the virus. While both arguments have justifications of their own, quantitative analysis of how these terms are being used in real life is lacking. In this paper, we attempt to fill this gap with fine-grained analysis. We find that tweets with a controversial term can be easily distinguished from those with neutral terms using state-of-the-art classifiers, that they cover different substantive topics, and that they possess different linguistic features reflecting sentiment and psychological states. All evidence suggests that the real life use of the controversial terms is distinctively different from that of the neutral terms.
Technological perspectives on laser speckle micro-rheology for cancer mechanobiology research.

Significance: The ability to measure the micro-mechanical properties of biological tissues and biomaterials is crucial for numerous fields of cancer research, including tumor mechanobiology, tumor-targeting drug delivery, and therapeutic development. Aim: Our goal is to provide a renewed perspective on the mainstream techniques used for micro-mechanical evaluation of biological tissues and biomimetic scaffoldings. We specifically focus on portraying the outlook of laser speckle micro-rheology (LSM), a technology that quantifies the mechanical properties of biomaterials and tissues in a rapid, non-contact manner. Approach: First, we briefly explain the motivation and significance of evaluating the tissue micro-mechanics in various fields of basic and translational cancer research and introduce the key concepts and quantitative metrics used to explain the mechanical properties of tissue. This is followed by reviewing the general active and passive themes of measuring micro-mechanics. Next, we focus on LSM and elaborate on the theoretical grounds and working principles of this technique. Then, the perspective for measuring the micro-mechanical properties via LSM is outlined. Finally, we draw an overview picture of LSM in cancer mechanobiology research. Results: With the continued emergence of new approaches for measuring the mechanical attributes of biological tissues, the field of micro-mechanical imaging is at its boom. As one of these competent innovations, LSM presents a tremendous potential for both technical maturation and prospective applications in cancer biomechanics and mechanobiology research. Conclusion: By elaborating the current viewpoint of LSM, we expect to accelerate the expansion of this approach to new territories in both technological domains and applied fields. This renewed perspective on LSM may also serve as a road map for other micro-mechanical measurement concepts to be applied for answering mechanobiological questions.
The Whitman of "Specimen Days"

SPECIMEN DAYS consists of fifteen pages of "an off-hand letter" of autobiographical information, another seventy-five pages of "Diary jottings, war-memoranda of 1862?'65," and another one hundred and fifty or so pages of "Nature-notes of 1877?'81" and reports of journeys to the West, Canada, New York, and Boston, mixed in with short essays on literature and on contemporaries like Carlyle, Longfellow, and Emerson. It was published with Collect, which includes "Democratic Vistas," towards its beginning, as well as an essay on the "Origins of Attempted Secession," two prefaces, from 1872 and 1876, and a lecture on the "Death of Abraham Lincoln," to which "Notes Left Over" and "Pieces in Early Youth" were also appended. All this is quite a conglomeration of odds and ends to respond to in any aesthetic way, and Walt Whitman disarms us further by telling us at the outset that the materials of Specimen Days and Collect, "incongruous and full of skips and jumps," were "all bundled up and tied by a big string."1 He avows it must be "the most wayward, spontaneous, fragmentary book ever printed," for what he did was "tumble the thing together, letting hurry and crudeness tell the story better than fine work" (690). But tell what "story"? It is true that the book is basically autobiograph ical. If we place it together with November Boughs and Good-Bye my Fancy, we may have before us the material for the Walt Whitman autobiography. It would be tempting to rearrange the pieces with a bit of creativity. His reminiscence of New Orleans in 1848 would find its place with "Through Eight Years" in the late pages ofthat autobiographical letter. The remark able sketch of Lincoln arriving in New York, at the Astor House in 1861, to "sulky, unbroken silence" (1038), might be moved up from Collect to where it "belongs," just before Whitman's war memoranda. And that
In-situ Production of High Density Polyethylene and Other Useful Materials on Mars

This paper describes a revolutionary materials structure and power storage concept based on the in-situ production of abiotic carbon 4 compounds. One of the largest single mass penalties required to support the human exploration of Mars is the surface habitat. This proposal will use physical chemical technologies to produce high density polyethylene (HDPE) inflatable structures and construction materials from Mars atmospheric CO2. The formation of polyethylene from Mars CO2 is based on the use of the Sabatier and modified Fischer Tropsch reactions. The proposed system will fully integrate with existing in-situ propellant production concepts. The technology will also be capable of supplementing human caloric requirements, providing solid and liquid fuels for energy storage, and providing significant reduction in mission risk. The NASA Mars Reference Mission Definition Team estimated that a conventional Mars surface habitat structure would weigh 10 tonnes. It is estimated that this technology could reduce this mass by 80%. This reduction in mass will significantly contribute to the reduction in total mission cost need to make a Mars mission a reality. In addition the potential reduction of risk provided by the ability to produce C4 and potentially higher carbon based materials in-situ on Mars is significant. Food, fuel, and shelter are only three of many requirements that would be impacted by this research.
The Liquid-Vapor Transition in Porous Plug Operation

The porous plug is a proven method for phase separation in superfluid helium dewars operating in zero gravity. The principal operating regimes have been identified in laboratory experiments on porous plugs. In this paper a description of porous plug operation is given, and a new explanation is presented for the observed transition in the m vs. ΔP characteristic. Theoretical results are in qualitative agreement with experimental data.
Chapter 10: Infrared and Raman microscopy in cell biology.

Abstract This chapter presents novel microscopic methods to monitor cell biological processes of live or fixed cells without the use of any dye, stains, or other contrast agent. These methods are based on spectral techniques that detect inherent spectroscopic properties of biochemical constituents of cells, or parts thereof. Two different modalities have been developed for this task. One of them is infrared micro‐spectroscopy, in which an average snapshot of a cell's biochemical composition is collected at a spatial resolution of typically 25 μm. This technique, which is extremely sensitive and can collect such a snapshot in fractions of a second, is particularly suited for studying gross biochemical changes. The other technique, Raman microscopy (also known as Raman micro‐spectroscopy), is ideally suited to study variations of cellular composition on the scale of subcellular organelles, since its spatial resolution is as good as that of fluorescence microscopy. Both techniques exhibit the fingerprint sensitivity of vibrational spectroscopy toward biochemical composition, and can be used to follow a variety of cellular processes.
The role of tribology research in the development of advanced lubricants

Economic and operational drivers, such as efficiency, reliability, maintenance costs, productivity and longevity, encourage new technology development in engineering equipment. Advanced lubricants are engineering components that are designed to support these drivers and to provide benefits to equipment owners and users well beyond what is expected from commodity lubricants. Tribology contributes to the full spectrum of advanced lubricant development, from evaluating and guiding the design of additive and base stock molecules to the formulation of lubricants that offer superior performance in full-scale machinery. This paper discusses the role of tribology research in this process, and gives examples of its application in solving field problems, balancing conflicting lubrication requirements and creating new fluids and business opportunities.
Distributed power control in wireless communication systems

Energy efficiency is a measure of performance in wireless networks. Therefore, controlling the transmitter power at a given node increases not only battery operating life, but also overall system capacity by successfully admitting new links. It is essential to find effective means of power control in point-to-point, broadcasting and multicasting scenarios. Wireless networking presents formidable challenges and we consider the problem of unicast or point-to-point (peer-to-peer) communication in wireless networks in the presence of other nodes. We study the feasibility of admitting new links in an wireless network operating area while maintaining quality of service (QoS), in terms of signal-to-interference ratio (SIR), for each link. SIR is maintained by adjusting the transmitter power levels at each source for a given link. Distributed power control (DPC) is a natural choice for this purpose because, unlike centralized power control, DPC should be able to adjust the power levels of each transmitted signal using local measurements, so that in a reasonable time, all nodes/links maintain the desired SIR. We present a suite of DPC schemes using both state space and optimal control methodology in discrete-time. Further, we prove the convergence of the overall network with our algorithm using Lyapunov stability analysis in comparison with a well known DPC scheme (see Bambos, N. et al., IEEE ACM Trans. on Networking, p.583-97, 2000). We present simulation results and comparisons for point to point communications in an overlapping scenario.
Alkaloid-dependent fetal muscle-type nicotinic acetylcholine receptor desensitization (1059.9)

The exposure of a developing embryo or fetus to teratogenic alkaloids from plants has the potential to cause developmental defects in humans and animals due to the inhibition of fetal movement. The...
Mechanosensory Neurons Innervating Aplysia Siphon Encode Noxious Stimuli and Display Nociceptive Sensitization

Numerous studies of learning and memory in Aplysia have focused on primary mechanosensory neurons innervating the siphon and having their somata in the left E (LE) cluster of the abdominal ganglion. Although systematic analyses have been made of the responses of these LE cells to mechanical stimulation of the tightly pinned siphon, little is known about corresponding responses when the siphon is unrestrained. The present study demonstrates that LE mechanosensory thresholds in the freely moving siphon are much higher than in the pinned siphon. Light tactile stimuli adequate to activate central neurons and reflexive siphon movements often fail to activate the LE cells when the siphon is unrestrained. Because the LE cells display increasing discharge to increasing pressures, with maximal activation by crushing or tearing stimuli that cause tissue injury, they satisfy accepted definitions of nociceptor. Indeed, they show similarities to vertebrate Aδ nociceptors, including a property apparently unique (among primary afferents) to nociceptors—sensitization by noxious stimulation of their receptive field. Either pinching or pinning the siphon decreases LE cell mechanosensory threshold and enhances soma excitability. Such stimuli reduce effective tissue compliance and cause neuromodulation that enhances sensory responsiveness. These results, and recent descriptions of predatory attacks on Aplysia , suggest that LE sensory neurons are tuned to grasping and crushing stimuli that threaten or produce bodily harm. LE cell sensitization has effects, resembling hyperalgesia and allodynia, that compensate for loss of sensory function during injury and help protect against subsequent threats.
Irreversibility paradox revised: onset of a center manifold in dissipative systems

A center-manifold-reduced Fokker-Planck equation is derived, starting from a time-reversible Liouville equation. The derivation is valid when there is a large separation of relaxation-time scales causing the phase-space contraction near a dynamic critical point. The paradox of breaking of time-reversal symmetry in the resulting Fokker-Planck equation at the onset of the center manifold is clarified.
Efficient skill learning using abstraction selection

We present an algorithm for selecting an appropriate abstraction when learning a new skill. We show empirically that it can consistently select an appropriate abstraction using very little sample data, and that it significantly improves skill learning performance in a reasonably large real-valued reinforcement learning domain.
Predicting Outcomes Using the Heart Failure Survival Score in Adults with Moderate or Complex Congenital Heart Disease

Background. Adults with congenital heart disease (CHD) face increased risk for morbidity and mortality with age, but few prognostic models exist. Objective. This study aims to assess whether the Heart Failure Survival Score (HFSS), which risk stratifies patients for heart transplantation, predicts outcomes in adults with moderate or complex CHD. Methods. This was a multicenter, retrospective study which identified 441 patients with moderate or complex CHD between 2005 and 2013, of whom 169 had all the HFSS parameters required to calculate the risk score. Because all study patients were deemed low risk by the HFSS, the score was dichotomized at the median (10.4). Outcomes included death, transplant or ventricular assist device (VAD), arrhythmia requiring treatment, nonelective cardio- vascular (CV) hospitalizations, and the composite. Associations of mean HFSS and HFSS <10.4 with each outcome were assessed. Results. The cohort had mean ± standard deviation age of 33.6 ± 12.6 years, peak VO2 21.8 ± 7.5 mL/kg/min, HFSS of 10.45 ± 0.88, and median years follow-up of 2.7 (1.1, 5.2). There were five deaths (2.8%), no transplants or VADs, 25 arrhythmias (14.8%), 22 CV hospitalizations (13%), and 39 composites (23.1%). Lower mean HFSS was observed for patients who died (9.6 ± 0.83 vs. 10.5 ± 0.87, P = .02), arrhythmia requiring treatment (10.0 ± 0.70 vs. 10.5 ± 0.89, P = .005), CV hospitalizations (9.9 ± 0.73 vs. 10.5 ± 0.88, P = .002), and the composite (10.0 ± 0.70 vs. 10.6 ± 0.89, P < .001). The positive and negative predictive values of HFSS <10.4 for the composite were 34% and 88% respectively, with sensitivity and specificity 74% and 56%. Conclusions. Although a low HFSS was significantly associated with outcomes, it did not adequately risk stratify adults with CHD, whose heterogeneous pathophysiology differs from that of the acquired heart failure population. Further studies are warranted to provide a more accurate prognosis.
Theory of Transmission Lines

Hopefully, by now you have a good understanding of waves propagating in space and in materials, including reflection and transmission at interfaces. Although not mentioned often enough, there were a number of assumptions implicit in this type of propagation. The most important was the fact that only plane waves were treated. In most cases, we also assumed the waves only propagate forward from the source, although reflections from interfaces cause waves to also propagate backward toward the source and these were treated in Chapter 13. While the existence of interfaces complicates treatment, it also allows for applications such as radar to be feasible. If we were to summarize the previous two chapters in a few words, we would say that all wave phenomena were treated in essentially infinite space; that is, plane waves were not restricted in space except for the occasional interface.
Effects of palm carotenoids in rat hepatic cytochrome P450-mediated benzo(a)pyrene metabolism.

Using benzo(a)pyrene(BaP) metabolism as a probe for chemical carcinogensis, in vitro and in vivo effects of palm-oil carotenoid [β-carotene (BC), α-carotene (AC), or canthaxanthin (CTX)] on BaP metabolism in the rat hepatic cytochrome P 450 −mediated monooxygenase system were studied. Apparent Michaelis-Menten constants (K m ) for formation of the precursor carcinogen, 7,8-dihydrodiol BaP, were found to be 14.4 (BC), 1.74 (AC), and 0.7 (CTX) μmol/L. The order of anticarcinogenic strength established in this study was BC >> AC > CTX. Increased formation of the detoxification intermediaten, 3-hydroxy BaP, with increased carotenoid concentration was observed
Developing Superior Negotiation Case Studies

While a great deal of excellent advice exists for producing case studies on managerially relevant topics in general, negotiation cases have distinctive aspects that merit explicit treatment. This article offers tailored advice for producing cases on negotiation and related topics (such as mediation and diplomacy) that are primarily intended for classroom discussion. It describes how to decide whether a negotiation-related case lead is worth developing and how to choose the perspective and case type most suited to one's objectives. Finally, in by far the longest part of the discussion, it offers ten “nuts and bolts” suggestions for structuring and producing an excellent negotiation case study.
Shifting bottom‐up and top‐down regulation of oak recruitment across a regional resource gradient

Aim Questions about the relative importance of top-down and bottom-up regulation of populations have long occupied ecologists. Recent work has explored how the strength of consumer- versus resourced-based limitation can shift in strength across both time and space, and indicates the need for larger scales of study across spatial resource gradients. A better understanding of how climate gradients affect population regulation is integral to conservation ecology, particularly in the context of global change. Location California. Methods We examined the effects of bottom-up (water limitation) and top-down (small mammal herbivory) forces on valley oak (Quercus lobata) sapling recruitment. We used existing literature on valley oak planting experiments and field data on natural populations at 26 sites across the species' distribution to explore how the factors regulating oak populations shift along a regional precipitation gradient. This approach allowed us to study time-integrated ecological processes in a long-lived system that would be impossible to manipulate in a strictly experimental setting. Results We found that the relative importance of top-down and bottom-up forces in limiting oak recruitment shifted across the precipitation gradient, with small mammalian herbivory (top-down) more important as long-term mean site precipitation increased, and factors related to moisture stress (bottom-up) increasingly important at lower precipitation levels. Main conclusions Our findings emphasize the importance of expanding the spatial scale of studies on population and community dynamics in order to better understand patterned variation in the multiple factors regulating them across resource gradients.
Halothane shortens acetylcholine receptor channel kinetics without affecting conductance

Abstract The extracellular patch-clamp technique was used to examine how halothane, a general anesthetic, affects the properties of single nicotinic acetylcholine receptor channels of embryonic Xenopus skeletal muscle cells grown in culture. Under control conditions, single-channel events showed a bimodal distribution on the basis of current amplitudes. This distribution was maintained during exposure to halothane and its washout. In addition, the mean current value of the low-and high-amplitude channels was unaffected by the presence of the anesthetic at clinically relevant concentrations. In contrast, halothane shortened the burst durations of both channel types in a concentration-dependent manner. This shortening of burst durations may be an expression of the more rapid relaxation of the channel protein to the nonconducting state, possibly due to the disordering effect of the anesthetic on membrane lipids in which the receptor protein is embedded. This functional change, in the behavior of the synaptic receptor, provides further direct information on the mode of action of general anesthetics.
Brain tumors in children- Current therapies and newer directions

Brain tumors are the second most common malignancy and the major cause of cancer related mortality in children. Though significant advances in neuroimaging, neurosurgery, radiation therapy and chemotherapy have evolved over the years, overall survival rate remains less than 75%. Malignant gliomas, high risk medulloblastoma with recurrence and infant brain tumors continue to be a major cause of therapeutic frustration. Even today diffuse pontine gliomas are universally fatal. Though tumors like low grade glioma have an overall excellent survival, recurrences and progression in eloquent areas pose therapeutic challenges. As research continues to unravel the biology including key molecules and signaling pathways responsible for the oncogenesis of different childhood brain tumors, novel targeted therapies are profiled. Identification of major targets like the Epidermal Growth factor Receptor (EGFR), Platelet Derived Growth Factor Receptor (PDGFR), Vascular Endothelial Growth factor (VEGF) and key signaling pathways like the MAPK and PI3K/Akt/mTOR has enabled us over the recent years to better understand tumor behavior and design tailored therapy. These efforts have improved overall survival of children with brain tumors. This review article discusses the current status of common brain tumors in children and the newer therapeutic approaches.
Bounds on the minimum energy-per-bit for bursty traffic in diamond networks

When data traffic in a wireless network is bursty, small amounts of data sporadically become available for transmission, and the energy cost associated with synchronizing the network nodes prior to each communication block is not negligible. Therefore, designing energy-efficient communication schemes for such asynchronous scenarios is of particular importance. In this paper, we show that, for symmetric diamond networks, by performing the tasks of synchronization and communication separately, it is possible to achieve the minimum energy-per-bit to within a factor that ranges from 2 in the synchronous case to 1 in the highly asynchronous regime.
Spatial topological constraints in a bimanual task.

Previous research has shown that the concurrent performance of two manual tasks results in a tight temporal coupling of the limbs. The intent of the present experiment was to investigate whether a similar coupling exists in the spatial domain. Subjects produced continuous drawing of circles and lines, one task at a time or bimanually, for a 20 s trial. In bimanual conditions in which subjects produced the circle task with one hand and the line task with the other, there was a clear tendency for the movement path of the circle task to become more line-like and the movement path of the line task to become more circle-like, i.e., a spatial magnet effect. A bimanual circle task and a bimanual line task did not exhibit changes in the movement path when compared to single-hand controls. In all bimanual conditions, the hands were tightly temporally locked. The evidence of temporal coupling and concomitant accommodation in the movement path for the conditions in which the hands were producing different shapes suggests that spatial constraints play a role in the governance of bimanual coordinated actions.
Isospin nonequilibrium in heavy-ion collisions at intermediate energies

The equilibration of the isospin degree of freedom in intermediate energy heavy-ion collisions was studied using an isospin-dependent BUU model. It is found that there exists a transition from the isospin equilibration at low energies to nonequilibration at high energies as the beam energy varies across the Fermi energy in central, asymmetric, heavy-ion collisions. At beam energies around 55 MeV/nucleon the composite system is in almost complete thermal equilibrium but isospin nonequilibrium breaks up into two primary hot residues with $\frac{N}{Z}$ ratios closely related to those of the target and projectile, respectively. The decay of these forward-backward moving residues results in the strong isospin asymmetry in space and the dependence of the isotopic composition of fragments on the $\frac{N}{Z}$ ratios of the target and projectile. These features are in good agreement with those found recently in experiments at NSCL/MSU and TAMU; implications of these findings are discussed.
Rhizobacteria with Exceptionally High Aryl Acylamidase Activity

Abstract Two Pseudomonas strains (RA2 and RB4) isolated from the rhizosphere of rice roots possessed exceptionally high aryl acylamidase activity (complete dissipation of 0.5 m M propanil [ N -(3,4-dichlorophenyl)propanamide] to dichloroaniline (DCA) in broth cultures within 24 hr). These microorganisms rapidly degraded acetanilide, 2′-nitroacetanilide (2′-NAA), and propanil to the corresponding aniline product in vivo and in vitro . No aryl acylamidase activity was found on several other substrates containing substituted amide bonds: the herbicides linuron [ N ′-(3,4-dichlorophenyl)- N -methoxy- N -methylurea] , diuron [ N ′-(3,4-dichlorophenyl)- N , N -dimethylurea], chlorpropham (1-methylethyl-3-chlorophenylcarbamate), pronamide [3,5-dichloro- N -(1-dimethyl-2-propynyl)benzamide], and alachlor [2-chloro- N -(2, 6-diethylphenyl)- N -(methoxymethyl)acetamide] and one metabolite (2-chloro-2′,6′-diethylacetanilide) of alachlor. Enzyme activity from both strains exhibited Michaelis-Menten kinetics using propanil as substrate with K m values of 0.22 and 0.39 m M and apparent V max values of 8.1 and 13.9 μmol DCA/mg whole-cell protein/hr for RA2 and RB4, respectively. V max values were severalfold higher than those of similar propanil aryl acylamidases, as described in the literature. With 2′-NAA as substrate, a linear relationship between concentration and activity was observed (3 to 4 μmol product/mg protein/hr at maximum solubility of 2′-NAA), indicating that enzyme saturation was not achieved. These high levels of aryl acylamidase activities are constitutive, since neither propanil nor linuron at 500 μ M was able to induce aryl acylamidase activity in these cell cultures. The insecticide carbaryl (1-naphthyl- N -methylcarbamate) inhibited enzyme activity in vivo and in vitro , but substantially only at concentrations above 100 μ M , with complete inhibition at 500 μ M . The enzyme activity is apparently cytosolic for both strains, and RA-2 had significant extracellular aryl acylamidase activity. These strains may facilitate rapid turnover of propanil residues in rice flood water and soils and may have potential as sources of aryl acylamidase for biotechnological applications.
Identification of radiolytic compounds from beef

Several previous papers have dealt with the forma-tion of radiolysis products in fats, triglycerides and fatty acids. Size excusion chromatography now pro-vides a means of separating larger, less volatile com-pounds, and its application to irradiated beef has resulted in a nearly complete analysis of the radio-lytic products formed. The components have been identified by gas chromatography/mass spectrometry (GC/MS).
Automated Gamma Knife dose planning

The Gamma Knife (Elekta Instruments, Inc., Atlanta, GA), a neurosurgical, highly focused radiation delivery device, is used to eradicate deep-seated anomalous tissue within the human brain by delivering a lethal dose of radiation to target tissue. This dose is the accumulated result of delivering sequential `shots' of radiation to the target where each shot is approximately 3D Gaussian in shape. The size and intensity of each shot can be adjusted by varying the time of radiation exposure and by using one of four collimator sizes ranging from 4 - 18 mm. Current dose planning requires that the dose plan be developed manually to cover the target, and only the target, with a desired minimum radiation intensity using a minimum number of shots. This is a laborious and subjective process which typically leads to suboptimal conformal target coverage by the dose. We have used adaptive simulated annealing/quenching followed by Nelder-Mead simplex optimization to automate the selection and placement of Gaussian-based `shots' to form a simulated dose plane. In order to make the computation of the problem tractable, the algorithm, based upon contouring and polygon clipping, takes a 2 1/2-D approach to defining the cost function. Several experiments have been performed where the optimizers have been given the freedom to vary the number of shots and the weight, collimator size, and 3D location of each shot. To data best results have been obtained by forcing the optimizers to use a fixed number of unweighted shots with each optimizer set free to vary the 3D location and collimator size of each shot. Our preliminary results indicate that this technology will radically decrease planning time while significantly increasing accuracy of conformal target coverage and reproducibility over current manual methods.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Environmental transmission scrambles coexistence patterns of avian influenza viruses.

Despite the recent accumulation of theoretical and empirical studies on avian influenza viruses (AIVs), the interactions among the diverse pool of strains remain poorly understood. One potential reason is multiple transmission routes. In this paper, we explore the behavior of a two-strain mathematical model of AIV dynamics with lifelong immunity to understand how the combination of direct and environmental transmission (via a persistent viral reservoir) determines strains coexistence and dominance. We find that coexistence requires the magnitude of basic reproductive ratios of the strains to be identical for each transmission route (R0dir and R0env) when cross-immunity is assumed to be perfect. Coexistence may be also possible when one strain is only directly transmitted and the contribution by environmental transmission is high. When we relax this assumption, the level of cross-protection does not modify coexistence criteria when strains are mainly environmentally transmitted, in contrast to the case where direct transmission dominates. Finally, when competitive exclusion is observed, the strain with the largest contribution from direct transmission outcompetes the other through competition for viral particle acquisition. Overall, we conclude that environmental transmission can affect the patterns of coexistence predicted by direct transmission models in complex ways.
Schmitt logic fills a project niche

The CMOS logic chips 4093B (QUAD NAND) and 4584B (HEX INVERTER) are Schmitt input devices with a potential for providing almost endless permutations of simple projects that can be geared to many levels of student ability and interest.
Some Inequalities for the Largest Eigenvalue of a Graph

Let λ(G) be the largest eigenvalue of the adjacency matrix of a graph G: We show that if G is Kp+1-free then ***** insert CODING here *****This inequality was first conjectured by Edwards and Elphick in 1983 and supersedes a series of previous results on upper bounds of λ(G).Let Ti denote the number of all i-cliques of G, λ = λ(G) and p = cl(G): We show ***** insert equation here *****Let δ be the minimal degree of G. We show ***** insert equation here *****This inequality supersedes inequalities of Stanley and Hong. It is sharp for regular graphs and for a class of graphs which are in some sense maximally irregular.
Site-directed Mutagenesis of the Yeast V-ATPase A Subunit

To investigate the function of residues at the catalytic nucleotide binding site of the V-ATPase, we have carried out site-directed mutagenesis of the VMA1 gene encoding the A subunit of the V-ATPase in yeast. Of the three cysteine residues that are conserved in all A subunits sequenced thus far, two (Cys284 and Cys539) appear essential for correct folding or stability of the A subunit. Mutation of the third cysteine (Cys261), located in the glycine-rich loop, to valine, generated an enzyme that was fully active but resistant to inhibition by N-ethylmalemide, 7-chloro-4-nitrobenz-2-oxa-1,3-diazole, and oxidation. To test the role of disulfide bond formation in regulation of vacuolar acidification in vivo, we have also determined the effect of the C261V mutant on targeting and processing of the soluble vacuolar protein carboxypeptidase Y. No difference in carboxypeptidase Y targeting or processing is observed between the wild type and C261V mutant, suggesting that disulfide bond formation in the V-ATPase A subunit is not essential for controlling vacuolar acidification in the Golgi. In addition, fluid phase endocytosis of Lucifer Yellow, quinacrine staining of acidic intracellular compartments and cell growth are indistinguishable in the C261V and wild type cells. Mutation of G250D in the glycine-rich loop also resulted in destabilization of the A subunit, whereas mutation of the lysine residue in this region (K263Q) gave a V-ATPase complex which showed normal levels of A subunit on the vacuolar membrane but was unstable to detergent solubilization and isolation and was totally lacking in V-ATPase activity. By contrast, mutation of the acidic residue, which has been postulated to play a direct catalytic role in the homologous F-ATPases (E286Q), had no effect on stability or assembly of the V-ATPase complex, but also led to complete loss of V-ATPase activity. The E286Q mutant showed labeling by 2-azido-[32P]ATP that was approximately 60% of that observed for wild type, suggesting that mutation of this glutamic acid residue affected primarily ATP hydrolysis rather than nucleotide binding.
Recent advances in the molecular genetics of resin biosynthesis and genetic engineering strategies to improve defenses in conifers

Since the first terpenoid synthase cDNA was obtained by the reverse genetic approach from grand fir, great progress in the molecular genetics of terpenoid formation has been made with angiosperms and genes encoding a monoterpene synthase, a sesquiterpene synthase, and a diterpene synthase. Tree killing bark beetles and their vectored fungal pathogens are the most destructive agents of conifer forests worldwide. Conifers defend against attack by the constitutive and inducible production of oleoresin that accumulates at the wound site to kill invaders and both flush and seal the injury. Although toxic to the bark beetle and fungal pathogen, oleoresin also plays a central role in the chemical ecology of these boring insects. Recent advances in the molecular genetics of terpenoid biosynthesis provide evidence for the evolutionary origins of oleoresin and permit consideration of genetic engineering strategies to improve conifer defenses as a component of modern forest biotechnology. This review described enzymes of resin biosynthesis, structural feathers of genes genomic intron and exon organization, pathway organization and evolution, resin production and accumulation, interactions between conifer and bark beetle, and engineering strategies to improve conifer defenses.
Insulin-like growth factor binding protein-1 is pre-synaptic at mouse neuromuscular synapses and is transported in nerve

In a previous study, we localized insulin-like growth factor binding protein 1 (IGFBP-1) to mouse neuromuscular junctions, and intramuscular nerves. To determine if pre-synaptic accumulation of IGFBP-1 occurred, we used double ligation of sciatic nerve in adult mice at different time points. IGFBPs were deteced by Western ligand blot (WLB) with125I-IGF-I. WLB and Western immunoblot (WIB) analysis of extracts from double-ligated nerves showed a delayed (6 days) increase of IGFBP-1 in the soluble fraction between the ligatures and distal to the distal ligature. For comparison we evaluated transport of neurofilament components, using WIB and confirmed the primarily anterograde transport of these intraaxonal proteins. These data suggest that expression of IGFBP-1 is both by activated Schwann cells as well as retrograde axonal transport with likely entry into the axon at the synapse.
Solution Phase Measurement of Both Weak σ and C−H···X− Hydrogen Bonding Interactions in Synthetic Anion Receptors

A series of tripodal receptors preorganize electron-deficient aromatic rings to bind halides in organic solvents using weak σ anion-to-arene interactions or C−H···X− hydrogen bonds. 1H NMR spectroscopy proves to be a powerful technique for quantifying binding in solution and determining the interaction motifs, even in cases of weak binding.
Design of a quadcopter for winning the Jerry Sanders Creative Design Competition

To win the Jerry Sanders Creative Design Competition, it is necessary to design a “cone transportation system” to transport cones to territories in the arena. There are three tiers of territories that award 1, 3, and 5 points when controlled for 10 seconds. Territories controlled at the end of the match are awarded 10, 30, and 40 points. The cone transportation system includes: (1) a vehicle, and (2) a mechanism for picking up and transporting cones. This project aims to design a quadcopter to pick-up and transport cones, as quadcopters are given a 3x point multiplier. With voltage relationship equations for brushless motors, a simulation was developed to determine optimal quadcopter size and rotor type. Thus, the advantages of using a quadcopter were verified.
Prediction of auditory spatial acuity from neural images on the owl's auditory space map

The owl can discriminate changes in the location of sound sources as small as 3° and can aim its head to within 2° of a source1,2. A typical neuron in its midbrain space map has a spatial receptive field that spans 40°—a width that is many times the behavioural threshold3. Here we have quantitatively examined the relationship between neuronal activity and perceptual acuity in the auditory space map in the barn owl midbrain. By analysing changes in firing rate resulting from small changes of stimulus azimuth, we show that most neurons can reliably signal changes in source location that are smaller than the behavioural threshold. Each source is represented in the space map by a focus of activity in a population of neurons. Displacement of the source causes the pattern of activity in this population to change. We show that this change predicts the owl's ability to detect a change in source location.
The utility of conscious thinking on higher-order theory

Higher-order theories of consciousness posit that a mental state is conscious by virtue of being represented by another mental state, which is therefore a higher-order representation (HOR). Whether HORs are construed as thoughts or experiences, higher-order theorists have generally contested whether such metarepresentations have any significant cognitive function. In this paper, I argue that they do, focusing on the value of conscious thinking, as distinguished from conscious perceiving, conscious feeling, and other forms of conscious mentality. A thinking process is constituted by propositional-attitude states, and during conscious thinking some or all of these states would be targeted by HORs. Since cases of nonconscious thinking are widely accepted, the question arises as to the use of representing one's thoughts during thinking. Contra the views of Armstrong and Rolls, I argue that HORs do not facilitate first-order thinking. Rather, I propose that such representations enable reasoning about one's act...
Reevaluation of Mimosa biuncifera and M. texana (Leguminosae: Mimosoideae)

Mimosa biuncifera, as currently defined in southwestern United States, is shown to comprise two related species,M. biuncifera s. str. andM. texana, distinguished primarily by position of the nodal aculei. Taxonomic synonyms ofM. biuncifera areM. lindheimeri andM. warnockii (the first undisputed, the second provisional);M. texana includesM. wherryana.
Imaginative Play and Logical Thinking in Young Children

Abstract To examine the relationship between imaginative play and logical thinking in young children, 65 children ranging in age from 4 to 7 years were interviewed or observed to assess their level of imaginative play and were administered Piaget-derived logical-thinking tasks. It was found that the relationship varied across ages. Imaginative play was positively correlated with social perspective taking in 5- and 6-year-old children. Imaginative play was negatively correlated with spatial perspective taking and multiplication of classes in 5-year-old children.
A biomechanical evaluation of tibiofemoral rotation in anterior cruciate deficient knees during walking and running

ACL injury has been associated with increased insta bility of the knee in both in vitro and in vivo studies using passively applied forces. This study assessed tibiofemoral rotation after ACL injury during the func tional activity of treadmill ambulation using a triaxial electrogoniometer. Isometric and isokinetic peak torques of the quadriceps and hamstrings were ob tained using the Cybex II isokinetic dynamometer.Significant increases in tibiofemoral rotation were noted with increased running speed in the injured and normal knees. The degree of rotation in the injured limb did not significantly exceed that of the normal limb. Isokinetic strength of the quadriceps and hamstrings correlates significantly with the observed extent of ro tation.
Effect of metal/bulk-heterojunction interfacial properties on organic photovoltaic device performance

Interfacial properties between evaporated metal contacts and active layer in organic photovoltaic devices critically affect device performance. Through a controlled mechanical delamination method, the interfaces between annealed P3HT:PCBM BHJ layer and Al or Ag electrodes are revealed for direct chemical characterization. The difference in the interfacial, rather than bulk, properties account for the different OPV device performance.
Corn Growth Response to Elevated CO2 Varies with the Amount of Nitrogen Applied

Corn, with C4 photosynthetic metabolism, often has no photosynthetic or yield response to elevated carbon dioxide concentrations. In C3 species, the yield stimulation at elevated carbon dioxide concentrations often decreases with nitrogen limitation. I tested whether such a nitrogen interaction occurred in corn, by growing sweet corn in field plots in open top chambers at ambient and elevated (ambient + 180 mmol·mol-1) carbon dioxide concentrations for four seasons, with six nitrogen application rates, ranging from half to twice the locally recommended rate. At the recommended rate of nitrogen application, no carbon dioxide effect on production occurred. However, both ear and leaf plus stem biomass were lower for the elevated carbon dioxide treatment than for the ambient treatment at less than the recommended rate of nitrogen application, and higher at the highest rates of nitrogen application. There were no significant responses of mid-day leaf gas exchange rates to nitrogen application rate for either carbon dioxide treatment, and elevated carbon dioxide did not significantly increase leaf carbon dioxide assimilation rates at any nitrogen level. Leaf area index during vegetative growth increased more with nitrogen application rate at elevated than at ambient carbon dioxide. It is concluded that elevated carbon dioxide increased the responsiveness of corn growth to nitrogen application by increasing the response of leaf area to nitrogen application rate, and that elevated carbon dioxide increased the amount of nitrogen required to achieve maximum yields.
Methods of teaching and evaluating electrocardiogram interpretation skills among cardiology fellowship programs in the United States.

Abstract Background This study examines the methods used by cardiology training programs within the United States to teach electrocardiogram (ECG) interpretation and prepare fellows for the American Board of Internal Medicine board examination. Methods A link to an 18-question Web-based survey was electronically mailed to 198 fellowship directors in the United States. Results The response rate was 45%. Most participating programs were university hospitals or affiliates (77%) and of moderate size (at least 11 total fellows [72%]). Programs were coordinated by senior (68%) general (60%) cardiologists. Only 42% of the programs performed formal testing. The American Board of Internal Medicine answer sheet was used by most faculty (92%) when teaching ECG interpretation. Conclusions Teaching of ECG interpretation varies among US fellowship programs. Coordination of curricula is performed by senior faculty, likely reflecting a trend toward subspecialization and dilution of ECG expertise among younger faculty. Future endeavors should focus on curriculum standardization with regular competency assessment.
Real time, in situ particle monitoring of the Applied Materials PI9200 ion implanter

Abstract Real time monitoring of particles in the process chamber and the roughing line of high current implanters has recently been of invaluable assistance to equipment manufacturers and fabrication Une process engineers. Earlier in situ particle monitors were limited in their performance by the size (>0.5 μm), velocity ( 0.22 μm, installed in a PI9200 ion implanter are discussed here. It is demonstrated that an equipment engineer can study, test, and improve autoclean cycles with the effect of any hardware change. The development of SPC charts and possible processing interlocks are discussed.