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Neutralization of budded Autographa californica NPV by a monoclonal antibody: identification of the target antigen.
A neutralizing monoclonal antibody of the budded phenotype of Autographa californica nuclear polyhedrons virus did not react with the occluded form of the virus as determined by neutralization, ELISA, and indirect immunoperoxidase staining. The antibody did react with the surface of infected cells in the prepolyhedra stage of cytopathic effect, the period of active virus budding. Immunoelectron microscopy indicated the antigen(s) reactive with the neutralizing antibody was present all around the viral envelope, but was more highly concentrated at the end with peplomers. Four proteins were immunoprecipitated from solubilized, radiolabeled budded virus preparations with the monoclonal antibody. The major protein had a molecular weight of approximately 64,000, while the other three were approximately 127,000, 59,000, and 49,000. All four proteins could be labeled with N-acetyl-d-[1-3H]glucosamine. This glycosylation reaction could be inhibited by tunicamycin
Dissipation of vibration in rough contact
The relationship which links the normal vibration occurring during the sliding of rough surfaces and the nominal contact area is investigated. Two regimes are found. In the first one, the vibrational level does not depend on the contact area, while in the second one, it is propor- tional to the contact area. A theoretical model is proposed. It is based on the assumption that the vibrational level results from a competition between two processes of vibration damping, the internal damping of the material and the contact damping occurring at the interface
Electron impact excitations of S2 molecules
Low-energy electron impact excitations of S_2 molecules are studied using the
fixed-bond R-matrix method based on state-averaged complete active space SCF
orbitals. Integral cross sections are calculated for elastic electron collision
as well as impact excitation of the 7 lowest excited electronic states. Also,
differential cross sections are obtained for elastic collision and excitation
of the a^1 Delta_g, b^1 Sigma_g^+ and B^3 Sigma_u^- states. The integrated
cross section of optically allowed excitation of the B^3 Sigma_u^- state agrees
reasonably well with the available theoretical result.Comment: 12 pages, 3 figures. Chemical Physics Letters, in pres
Bandit Models of Human Behavior: Reward Processing in Mental Disorders
Drawing an inspiration from behavioral studies of human decision making, we
propose here a general parametric framework for multi-armed bandit problem,
which extends the standard Thompson Sampling approach to incorporate reward
processing biases associated with several neurological and psychiatric
conditions, including Parkinson's and Alzheimer's diseases,
attention-deficit/hyperactivity disorder (ADHD), addiction, and chronic pain.
We demonstrate empirically that the proposed parametric approach can often
outperform the baseline Thompson Sampling on a variety of datasets. Moreover,
from the behavioral modeling perspective, our parametric framework can be
viewed as a first step towards a unifying computational model capturing reward
processing abnormalities across multiple mental conditions.Comment: Conference on Artificial General Intelligence, AGI-1
Thermal and Non-thermal X-Rays from the LMC Super Bubble 30 Dor C
We report on the discovery of thermal and non-thermal X-rays from the shells
of the super bubble (SB) 30 Dor C in the Large Magellanic Cloud (LMC). The
X-ray morphology is a nearly circular shell with a radius of about 40 pc, which
is bright on the northern and western sides. The spectra of the shells are
different from region to region. The southern shell shows clear emission lines,
and is well fitted with a model of a thin-thermal plasma (kT = 0.21keV) in
non-equilibrium ionization (NEI) plus a power-law component. This thermal
plasma is located inside of the H alpha emission, which is the outer edge of
the shell of the SB. The northern and western sides of the SB are dim in H
alpha emission, but are bright in non-thermal (power-law) X-rays with a photon
index of 2.1-2.9. The non-thermal X-ray shell traces the outer boundary of the
radio shell. These features of thin-thermal and non-thermal X-rays are similar
to those of SN 1006, a prototype of synchrotron X-ray shell, but the
non-thermal component of 30 Dor C is about ten-times brighter than that of SN
1006. 30 Dor C is the first candidate of an extragalactic SB, in which
energetic electrons are accelerating in the shell. The age is much older than
that of SN 1006, and hence the particle acceleration time in this SB may be
longer than those in normal shell-like SNRs. We found point-like sources
associated with some of tight star clusters. The X-ray luminosity and spectrum
are consistent with those of young clusters of massive stars. Point-like
sources with non-thermal spectra are also found in the SB. These may be
background objects (AGNs) or stellar remnants (neutron stars or black holes).Comment: 11 pages, 6 figures, Accepted for publication in ApJ, the paper with
full resolution images in
http://www-cr.scphys.kyoto-u.ac.jp/member/bamba/Paper/30DorC.pd
Collaborative Pharmacy Practice: An Update
Collaborative practice among health professionals is slowly coming of age, given the global focus on efficiency and effectiveness of care to achieve positive patient outcomes and to reduce the economic burden of fragmented care. Collaborative pharmacy practice (CPP) is accordingly evolving within different models including: disease management, medication therapy management, patient centered medical home, and accountable care organizations. Pharmacist roles in these models relate to drug therapy management and include therapy introduction, adjustment, or discontinuation, patient counseling and education, and identification, resolution, and prevention of problems leading to drug interactions and adverse reactions. Most forms of CPP occur with physicians in various settings. Collaborative practice agreements exist in many states in the US and are mentioned in the International Pharmaceutical Federation policy statement. Impetus for CPP comes from health system and economic concerns, as well as from a regulatory push. There are positive examples in community, ambulatory care, and inpatient settings that have well documented protocols, indicators of care, and measurement and reporting of clinical, economic, and patient reported outcomes; however, implementation of the practice is still not widespread. Conceptual and implementation challenges include health professional training, attitudes, confidence and comfort levels, power and communication issues, logistic barriers of time, workload, proximity, resistance to establish and adopt regulations, and importantly, payment models. Some of the attitudinal and perceptual challenges can be mitigated by incorporation of interprofessional concepts and practice in health profession education. Other challenges need to be addressed across health systems, given the inefficiencies and problems that arise from lack of communication and coordination of patient care including medication nonadherence, errors and patient safety, complexity of compounded health problems, and potential liability. The existing evidence needs to be examined to address some challenges and improve infrastructure for CPP
Predictors of Successful Decannulation Using a Tracheostomy Retainer in Patients with Prolonged Weaning and Persisting Respiratory Failure
Background: For percutaneously tracheostomized patients with prolonged weaning and persisting respiratory failure, the adequate time point for safe decannulation and switch to noninvasive ventilation is an important clinical issue. Objectives: We aimed to evaluate the usefulness of a tracheostomy retainer (TR) and the predictors of successful decannulation. Methods: We studied 166 of 384 patients with prolonged weaning in whom a TR was inserted into a tracheostoma. Patients were analyzed with regard to successful decannulation and characterized by blood gas values, the duration of previous spontaneous breathing, Simplified Acute Physiology Score (SAPS) and laboratory parameters. Results: In 47 patients (28.3%) recannulation was necessary, mostly due to respiratory decompensation and aspiration. Overall, 80.6% of the patients could be liberated from a tracheostomy with the help of a TR. The need for recannulation was associated with a shorter duration of spontaneous breathing within the last 24/48 h (p < 0.01 each), lower arterial oxygen tension (p = 0.025), greater age (p = 0.025), and a higher creatinine level (p = 0.003) and SAPS (p < 0.001). The risk for recannulation was 9.5% when patients breathed spontaneously for 19-24 h within the 24 h prior to decannulation, but 75.0% when patients breathed for only 0-6 h without ventilatory support (p < 0.001). According to ROC analysis, the SAPS best predicted successful decannulation {[}AUC 0.725 (95% CI: 0.634-0.815), p < 0.001]. Recannulated patients had longer durations of intubation (p = 0.046), tracheostomy (p = 0.003) and hospital stay (p < 0.001). Conclusion: In percutaneously tracheostomized patients with prolonged weaning, the use of a TR seems to facilitate and improve the weaning process considerably. The duration of spontaneous breathing prior to decannulation, age and oxygenation describe the risk for recannulation in these patients. Copyright (c) 2012 S. Karger AG, Base
Minimally invasive determination of mRNA concentration in single living bacteria
Fluorescence correlation spectroscopy (FCS) has permitted the characterization of high concentrations of noncoding RNAs in a single living bacterium. Here, we extend the use of FCS to low concentrations of coding RNAs in single living cells. We genetically fuse a red fluorescent protein (RFP) gene and two binding sites for an RNA-binding protein, whose translated product is the RFP protein alone. Using this construct, we determine in single cells both the absolute [mRNA] concentration and the associated [RFP] expressed from an inducible plasmid. We find that the FCS method allows us to reliably monitor in real-time [mRNA] down to ∼40 nM (i.e. approximately two transcripts per volume of detection). To validate these measurements, we show that [mRNA] is proportional to the associated expression of the RFP protein. This FCS-based technique establishes a framework for minimally invasive measurements of mRNA concentration in individual living bacteria
Thermoelectric Properties of Novel Semimetals: A Case Study of YbMnSb<sub>2</sub>
The emerging class of topological materials provides a platform to engineer exotic electronic structures for a variety of applications. As complex band structures and Fermi surfaces can directly benefit thermoelectric performance it is important to identify the role of featured topological bands in thermoelectrics particularly when there are coexisting classic regular bands. In this work, the contribution of Dirac bands to thermoelectric performance and their ability to concurrently achieve large thermopower and low resistivity in novel semimetals is investigated. By examining the YbMnSb2 nodal line semimetal as an example, the Dirac bands appear to provide a low resistivity along the direction in which they are highly dispersive. Moreover, because of the regular-band-provided density of states, a large Seebeck coefficient over 160 µV K−1 at 300 K is achieved in both directions, which is very high for a semimetal with high carrier concentration. The combined highly dispersive Dirac and regular bands lead to ten times increase in power factor, reaching a value of 2.1 mW m−1 K−2 at 300 K. The present work highlights the potential of such novel semimetals for unusual electronic transport properties and guides strategies towards high thermoelectric performance. © 2020 The Authors. Advanced Materials published by Wiley-VCH Gmb
Temporal Control over Transient Chemical Systems using Structurally Diverse Chemical Fuels
The next generation of adaptive, intelligent chemical systems will rely on a continuous supply of energy to maintain the functional state. Such systems will require chemical methodology that provides precise control over the energy dissipation process, and thus, the lifetime of the transiently activated function. This manuscript reports on the use of structurally diverse chemical fuels to control the lifetime of two different systems under dissipative conditions: transient signal generation and the transient formation of self-assembled aggregates. The energy stored in the fuels is dissipated at different rates by an enzyme, which in-stalls a dependence of the lifetime of the active system on the chemical structure of the fuel. In the case of transient signal generation, it is shown that different chemical fuels can be used to generate a vast range of signal profiles, allowing temporal control over two orders of magnitude. Regarding self-assembly under dissipative conditions, the ability to control the lifetime using different fuels turns out to be particularly important as stable aggregates are formed only at well-defined surfactant/fuel ratios, meaning that temporal control cannot be achieved by simply changing the fuel concentration
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