cssi/SciSciGPT-SciSciNet huggingface dataset:
The von Hippel–Lindau Cullin-RING E3 ubiquitin ligase regulates APOBEC3 cytidine deaminases

The 7 members of the A3 family of cytidine deaminases (A3A to A3H) share a conserved catalytic activity that converts cytidines in single-stranded (ss) DNA into uridines, thereby inducing mutations. After their initial identification as cell-intrinsic defenses against HIV and other retroviruses, A3s were also found to impair many additional viruses. Moreover, some of the A3 proteins (A3A, A3B, and A3H haplotype I) are dysregulated in cancer cells, thereby causing chromosomal mutations that can be selected to fuel progression of malignancy. Viral mechanisms that increase transcription of A3 genes or induce proteasomal degradation of A3 proteins have been characterized. However, only a few underlying biological mechanisms regulating levels of A3s in uninfected cells have been described. Here, we characterize that the von Hippel–Lindau tumor suppressor (pVHL), via its CRLpVHL, induces degradation of all 7 A3 proteins. Two independent lines of evidence supported the conclusion that the multiprotein CRLpVHL complex is necessary for A3 degradation. CRLpVHL more effectively induced degradation of nuclear, procancer A3 (A3B) than the cytoplasmic, antiretroviral A3 (A3G). These results identify specific cellular factors that regulate A3s post-translationally.
Public war and the requirement of legitimate authority

This paper offers a non-reductivist account of the requirement of legitimate authority in warfare (RLA). I first advance a distinction between private and public wars. A war is private where individuals defend their private rights with their private means. A war is public where it either aims to defend public rights (e.g., a people’s right to self-governance) or relies on public means (e.g., conscription and taxation). I argue that RLA applies to public war but not private war. A public war waged by a belligerent without legitimate authority involves a form of illegitimate domination of the people. Contra the conventional wisdom that RLA is only an ad bellum principle, I show that RLA is also a vital in bello principle. Relying on the Kantian non-voluntarist account of political authority, I argue that only legitimate states have the right to wage public wars. However, I also contend that RLA is not an absolute requirement, even regarding the justice of public war. Under extremely unfavorable conditions, this requirement may be overridden by weighty considerations in favor of resorting to public war without legitimate authority. In sum, my account of RLA protects ordinary people from illegitimate coercion involved in guerrilla warfare in general yet generates proper permission for responsible, aspiring state founders to secure social justice by coercive means under extraordinary situations.
Pediatric Hematology/Oncology Nurse Spirituality, Stress, Coping, Spiritual Well-being, and Intent to Leave: A Mixed-method Study.

Background: Intense emotional demands of oncology nursing create a stressful work environment and increase the likelihood of leaving. The study aims to explore, describe, and understand how pediatr...
Is Homosexuality in the Priesthood Diminishing? Evidence from Sexual Attitudes, Behaviors, and Contexts of Catholic Clergy in the United States

This study explores the results of the 2021 Survey of American Catholic Priests, an effort to replicate the 2002 Los Angeles Times survey of priests, in evaluating stability and change in the sexual beliefs, dispositions, and behaviors of Catholic priests in the United States. Reinforcing widespread perceptions, we find that younger priests hold more conservative sexual attitudes than their older counterparts. We also find them to be less likely to report homosexual attraction, and we perform a very basic projection of the future sexual orientation composition of the US clergy using baseline assumptions and a cohort replacement model. We find that orientation and orthodoxy are intertwined, with heterosexual priests reporting higher celibacy adherence and belief that behaviors identified by the Church as sins are in fact sins. Our analyses further suggest that the present lower clergy supply is largely explicable by a decline in progressive priests.
Nonlinearities in the Dynamics and Control of Space Structures: Some Issues for Computational Mechanics

This article deals with nonlinearities that arise in the study of dynamics and control of highly flexible large-space-structures. Broadly speaking, these nonlinearities have various origins: (i) geometrical: due to large deformations and large rotations of these structures and their members; (ii) inertia: depending on the coordinate systems used in characterizing the overall dynamic motion as well as elastic deformations; (iii) damping: due to nonlinear hysterisis in flexible joints; viscoelastic coatings etc. , and (iv) material: due to the nonlinear behavior of the structural material. The geometrical and material nonlinearities affect the “tangent stiffness operator” of the structure; the inertia nonlinearities affect the “tangent inertia operator”.
Alternate Semi-Aqueous Precision Cleaning Techniques: Steam Cleaning and Supersonic Gas/Liquid Cleaning Systems

Publisher Summary This chapter describes two alternate semi-aqueous cleaning methods, precision steam cleaning and supersonic gasliquid cleaning. Steam can be a practical and environmentally friendly method to clean without the use of solvents. Vapor steam cleaning has been used in a variety of applications from household to industrial to military to medical. Simply boiling water can generate steam; however, it is the combination of temperature and pressure that makes steam cleaning effective. A steam cleaner is a highly beneficial piece of equipment for all home, commercial, and industrial applications requiring sanitizing, disinfecting, and cleaning capabilities in a single machine. Two alternate semi-aqueous cleaning techniques have been developed for various precision cleaning applications. Vapor steam cleaning employs dry superheated steam to remove surface contaminants. It is a low-cost, effective method for precision cleaning and for decontamination of microbially contaminated surfaces. Supersonic gas-liquid cleaning is based on accelerating the cleaning liquid, suspended as droplets in a gas stream, to supersonic velocities through a converging-diverging nozzle. The gas–liquid mixture has the kinetic energy to very effectively remove surface contaminants. This method can also be used for cleanliness verification. Both methods use very low volumes of aqueous liquids and are viable alternatives to solvent cleaning in many applications.
Conducting Action Research in a Rural High School Setting Using Peers as Corrective Reading Instructors for Students with Disabilities

The purpose of this study was to analyze the effects of a peer-delivered Corrective Reading Program (CRP) (Engelmann, Hanner, & Johnson, 1989) with repeated reading in a rural high school setting. ...
Which Side Are You On?: An Inside History of the Folk Music Revival in America

Reviewed Medium: book Authors: Dick Weissman Year: 2005 Pages: 296 Publisher: Continuum ISBN: 0826416985 (hard cover). Prices: $24.95 USD(hard cover).
Time Evolution of Unimolecular Processes in Isolated Molecules by Crossed Laser and Molecular Beams

A new technique, double absorption photofragment spectroscopy (DAPS), has been developed in order to follow the time evolution of unimolecular processes in isolated molecules. Molecules removed from collisions in a molecular beam are prepared in well defined initial states by an initiation laser pulse As this state distribution evolves, it is monitored as a function of time by a second, delayed, probe laser pulse which, by exciting the molecules to a higher dissociative state, forces them to emit information-carrying particles. These particles, molecular fragments from photodissociation, are detected by photofragment spectroscopy, which can be used to derive information about the time evolution of the unimolecular process by following changes in such parameters as population, angular distribution, fragmentation pattern, and energy partitioning. As an initial demonstration of this technique, the predissociation of the iodine B state has been studied. The lifetime for the B state was found to vary between 770 and 1600 nsec depending on the v′ J′ population distribution prepared by the initiation laser pulse. In addition, the characterization of a state, invisible in the ordinary absorption spectrum because transition to it is parity forbidden, is illustrated through the sequential absorption of two photons.
Do the self‐employed value autonomy more than employees?

Purpose – The purpose of this paper is to examine whether the relations between perceived job autonomy and attitudes are stronger among self‐employed than employees.Design/methodology/approach – Four samples (total n=25,974), consisting of self‐report data from working adults, were used. In each, participants were classified under three work arrangements: owners of businesses employing others, independent contractors, and employees. The perceived job autonomy for each work arrangement was determined, as were the strengths of the relationship with attitudinal variables (job satisfaction, life satisfaction, professional commitment, and stress). Correlational analysis and hierarchical regression were used to test whether the strengths of these relationships were stronger among the self‐employed.Findings – In all four samples, both types of self‐employed reported more job autonomy than employees. In all samples and within all work arrangements, the relationships between job autonomy were statistically signifi...
Holding the Line: Customs and Border Protection’s Expansion of the Border Search Exception and the Ensuing Destruction of Interior Fourth Amendment Rights

While the Fourth Amendment governs every search conducted by government agents within the United States, the Supreme Court has sanctioned diminished Fourth Amendment protections at the border by holding warrantless and suspicionless routine border searches constitutional due to the “special need” of the government to protect its people. However, in permitting this “Border Search Exception” to the Fourth Amendment, the Supreme Court has done so with a conception of the border in mind that does not bear resemblance to the “100-mile buffer zone” described in CBP’s regulations, and under which CBP now rests its authority for its push into the interior. Rather, in sanctioning reduced Fourth Amendment protections at the border, the Court employed a narrow, common understanding of what the country’s border means — the barrier zone between the United States and its international neighbors.This Note argues that the reduced Fourth Amendment protections at the physical border, sanctioned by the Supreme Court under the Border Search Exception doctrine, do not authorize CBP’s post-September 11 extension of suspicionless searches into the interior, to the outermost limits of the agency’s jurisdictional authority under INA § 287(a)(3) and CFR § 287.1(a)(2). In other words, CBP has usurped the investigative tools provided it for border protection work to achieve internal immigration enforcement under the guise of terrorism prevention. This expansion of diminished Fourth Amendment protections has resulted in constitutional violations that must be reigned in by the Supreme Court, if it is given the opportunity to do so, or by DHS itself, by amending 8 CFR § 287.1(a)(2) to reflect CBP’s limited authority away from the border. Part I of this Note provides an overview of Supreme Court jurisprudence regarding Fourth Amendment protections at the border, and of the statutory and regulatory sections that govern CBP’s authority away from border. Part II discusses CBP’s push into the interior of the country after September 11 to perform internal immigration checks — a job that belongs to CBP’s sister agency, Immigration and Customs Enforcement (ICE). Part III argues that the “100-mile border zone” promoted in CBP’s regulations under 8 CFR § 287.1(a)(2) has enabled CBP to assert authority to perform interior suspicionless searches, and that such action is in direct conflict with the limitations of the Border Search Exception. Part III also suggests a regulatory and internal agency fix to this Fourth Amendment problem.
Neuronal Nitric Oxide Synthase EXPRESSION IN ESCHERICHIA COLI, IRREVERSIBLE INHIBITION BY PHENYLDIAZENE, AND ACTIVE SITE TOPOLOGY

A gene coding for rat neuronal nitric oxide synthase (nNOS) has been cloned into pCWori and the vector has been expressed in Escherichia coli. The expressed enzyme has been purified with a final yield of purified protein of approximately 1 mg/g of wet cells. The recombinant protein reconstituted with calmodulin and Ca2+ exhibits spectroscopic and catalytic properties identical to those reported in the literature for nNOS. Reaction of recombinant nNOS with phenyldiazene produces a phenyl-iron (Fe•Ph) complex with a maximum at 470 nm. Formation of this complex is paralleled by inactivation of the enzyme and is inhibited by arginine, the natural substrate of the enzyme. Phenyl-iron complex formation does not alter the rate of electron transfer from the flavin domain to cytochrome c. Addition of ferricyanide triggers migration of the phenyl residue from the iron to the porphyrin nitrogens. The N-phenylprotoporphyrin isomers with the phenyl on the nitrogens of pyrrole rings B, A, C, and D are formed in, respectively, approximately a 14:20:21:45 ratio. The regioisomer pattern indicates that the active site of NOS is open to some extent above all four pyrrole rings but more so above pyrrole ring D. Arylhydrazines are thus not only a new class of inhibitors of nNOS but provide useful information on the active site topology of the enzyme.
High Intensity Polarized Electron Sources

The status of the polarized electron source development program at SLAC will be reviewed. Emission currents of 60 A, corresponding to a space charge limited current density of 180 A/cm2, have been obtained from GaAs photocathodes. Electron beam polarization 20% greater than that obtainable from GaAs cathodes has been observed from multilayer GaAs-GaAlAs structures. Work in progress to produce high beam polarization from II-IV-V2 chalcopyrite photocathodes will also be described.
Multisensor SIMD architecture for data fusion target tracking using the 21020 DSP family

Because of the evolution of Digital Signal Processing chips, a new Signal Computing chip, the Analog Devices 21020, was selected as the processor for nodes in a SIMD architecture which solves a data fusion target tracking problem. The solution is obtained by altering the gains of the sensors via feedback. >
pH EFFECTS ON THE STRUCTURE OF THE INNER HISTONES

The structure of the inner histone complex extracted from chicken erythrocyte chromatin with 2 M NaCl has been studied as a function of pH. At pH 6, the complex dissociates to (H3-H4)2 tetramer and H2A.H2B dimer, with little change in alpha-helix content (as monitored by circular dichroism at 222 mm). Although the circular dichroism of tyrosyl side chains is also largely unchanged by the dissociation, measurements of intrinsic fluorescence do suggest a change in the environment of one or more tyrosines as a result of dissociation. Below pH 4, the histones become partially unfolded, lose specific secondary and tertiary structure, and undergo nonspecific aggregation. Both the pH 6 and 4 transitions, which are largely reversible, parallel pH-induced structural changes of nucleosomes (Zama, M., Olins, D.E., Prescott, B. and Thomas, G.J. (1978) Nucleic Acids Res. 5, 3881-3897). The results are consistent with the presence of tyrosine residues at the histone subunit-subunit contacts and suggest that histone conformation within the globular regions is largely independent of histone-DNA interactions.
Almost tight upper bounds for the single cell and zone problems in three dimensions

We consider the problem of bounding the combinatorial complexity of a single cell in an arrangement of n low-degree algebraic surface patches in 3-space. We show that this complexity is O(n2+e), for any e>0, where the constant of proportionality depends on e and on the maximum degree of the given surfaces and of their boundaries. This extends several previous results, almost settles a 7-year-old open problem, and has applications to motion planning of general robot systems with three degrees of freedom. As a corollary of the above result, we show that the overall complexity of all the three-dimensional cells of an arrangement of n low-degree algebraic surface patches, intersected by an additional low-degree algebraic surface patch s (the so-called zone of s in the arrangement) is O(n2+e), for any e>0, where the constant of proportionality depends on e and on the maximum degree of the given surfaces and of their boundaries.
Thermal Decomposition Studies of a New, gem-Dinitroalkyl Nitramine 1,3,3-Trinitroazetidine ( TNAZ ).

The initial results from a study of the thermal decomposition of TNAZ and TNAZ-\.'sN02 using the simultaneous thermogravimetric modulated beam mass spectrometry (STMBMS) technique are presented. The major products formed in the decomposition of TNAZ are N02 and NO with slightly lesser amounts of H20, HCN, COIN2, C01!N20 and l-nitroso-Ld-dinitroazetidine (NDNAZ). The last mentioned product (NDNAZ) is shown to be an important intermediate in the decomposition of TNAZ and its decomposition has also been examined by synthesizing it independently. Major products formed in this decomposition of NDNAZare NO with smaller amounts of H20, HCN, COIN2 and C01!N20. The temporal behaviours of the ion signals associated with the various thermal decomposition products from TNAZ, TNAZ-I-15N02 and NDNAZ are also presented. They illustrate the evolution sequence of the various products that are associated with the different reaction pathways that control the decomposition of these materials. In particular, the study of the ISN-Iabeled sample revealed that N02 originates from both the likely sites in the TNAZ molecule and that the cleavage of the nitramine-N02 group precedes that of the C-N02 cleavage, resulting in similar sequences in the formation of NO and NDNAZ also.
Preliminary Study Of Cusptron Amplifier

The cusptron microwave tube concept is under development at NSWC as a compact high power device using the harmonic frequency generating scheme by an axis-rotating beam and a multivane circuit. Sixth and fourth harmonic frequencies have been independently generated with electronic efficiencies of approximately 10%. With this successful oscillator mode of operation, the cusptron is now being converted to an amplifier. The input and output couplers are one-turn loops located in different vanes. A TWT operating 4.0-8.0 GHz will be used as an RF driver. In this paper, we will present theoretical and experimental studies on the cusptron amplifier with a 30-50 keV, axis-rotating electron beam and a six-vane circuit.
Isolation and characterization of novel tetranucleotide microsatellite DNA markers for the spotted salamander, Ambystoma maculatum

Fifteen tetranucleotide microsatellite loci were identified and characterized for spotted salamanders (Ambystoma maculatum) collected from three vernal pools in the south-eastern USA. These markers revealed a high degree of genetic diversity (7–32 alleles per locus), heterozygosity (31.6–86.3%) and allelic heterogeneity (91% of comparisons were statistically significant). Considerable differentiation among populations was observed as genetic distances (chord) ranged between 0.50 and 0.65, and all FST values (0.08–0.14) were statistically significant. Moreover, genotypic assignment tests correctly classified all individuals to their respective collection. These markers should prove useful for investigating fine-scale population structure and mating system.
Recalling the single-FFT direct Poisson solve

Large Poisson’s equation problems arise in gradient-domain image compositing. Agarwala [2007] and Kazhdan and Hoppe [2008] recently presented iterative solution methods using a smooth correction term and multigrid with higher-order elements, respectively. In both papers, however, direct solution methods are somewhat glossed over. This work aims to remedy these omissions by presenting timing numbers for a classic single-FFT – so-called because it performs a fast Fourier transform only on one dimension of the image – solution method.
Subcultural evolution and illicit drug use

This article articulates a subcultural basis to the evolving popularity for different illicit drugs primarily based on empirical research in the United States, especially among inner-city populations. From this perspective, drug use emerges from a dialectic between drug subcultures with individual identity development. The prevailing culture and subcultures affect drugs' popularity by imparting significance to their use. Innovations, historical events, and individual choices can cause subcultures to emerge and change over time. This subcultural view provides insight into the widespread use of licit drug, the dynamics of drug eras (or epidemics), the formation of drug generations, and the apparent “gateway” phenomenon.
Mucosal cellular populations and distribution in the normal canine stomach.

Mucosal cellular populations and glandular thickness in the corpus of the canine stomach was assessed in 30 dogs. The average number of mucous neck cells per “swath” of full thickness mucosa over a width of 0.223 mm was 41 (S.E. ± 2.09), of parietal cells, 95 (S.E. ± 8.71), of chief cells 205 (S.E. ± 12.63). The average glandular thickness was 557 μ (S.E. ± 24.71). The distribution of cells in the stomachs of four additional dogs was determined. More mucous neck cells were noted in the glands of the juxta-antral and cardiac zones than in those of the corpus. Few parietal and chief cells were noted in the cardiac zone. In the corpus, however, these cells were abundant and evenly distributed. The data presented permit calculation of the total gastric mucosal cellular population of the stomach from an “average” 15 kg dog. The acid-pepsin secreting area has a volume of 35 cm3, and therefore contains 4.3× 108 parietal cells, 7.2 × 108 chief cells, and 1.4 × 108 mucous neck cells.
A New Framework of GPU-Accelerated Spectral Solvers: Collocation and Glerkin Methods for Systems of Coupled Elliptic Equations

Spectral methods are useful for applications that benefit from high-order precisions. However, if the same number of degrees of freedom is used, the computational cost of a spectral method is considerably higher than that of a general finite difference or finite element method. After the investigation in Chen et al. (J Comput Phys 250:555---564, 2013), we provide for the first time a framework of graphics processing units (GPU)-accelerated spectral methods for systems of coupled elliptic equations. The involved dense matrix computations, as the main obstacle for fast spectral methods on a traditional CPU, turns out to be an opportunity for high speedups on a many-core GPU. We obtain an order-of-magnitude speedup for solving 2-D and 3-D systems using a Kepler 20 GPU over a high-end multi-core processor, with two popular spectral methods, namely, the spectral collocation method and the spectral-Galerkin method. The new framework is applicable to systems of $$L$$ L coupled second-order equations with general boundary conditions, where $$L$$ L is an integer of moderate size. The ultimate goal is to apply the developed solver to complex and nonlinear time-dependent problems. As two interesting examples, a 2-D FitzHugh-Nagumo equation is solved with the spectral collocation method and a 3-D Cahn-Hilliard equation is solved with the spectral-Galerkin method. We thus demonstrate a practical solution for demanding problems that utilize high-order spatial resolution and longer run-times.
Effects of multiple scattering on fluorescence correlation spectroscopy measurements of particles moving within optically dense media

Fluorescence correlation spectroscopy (FCS) is increasingly being used to assess the movement of particles diffusing in complex, optically dense surroundings, in which case measurement conditions may complicate data interpretation. It is considered how a single-photon FCS measurement can be affected if the sample properties result in scattering of the incident light. FCS autocorrelation functions of Atto 488 dye molecules diffusing in solutions of polystyrene beads are measured, which acted as scatterers. Data indicated that a scattering-linked increase in the illuminated volume, as much as two fold, resulted in minimal increase in diffusivity. To analyze the illuminated beam profile, Monte-Carlo simulations were employed, which indicated a larger broadening of the beam along the axial than the radial directions, and a reduction of the incident intensity at the focal point. The broadening of the volume in the axial direction has only negligible effect on the measured diffusion time, since intensity fluctuations due to diffusion events in the radial direction are dominant in FCS measurements. Collectively, results indicate that multiple scattering does not result in FCS measurement artifacts and thus, when sufficient signal intensity is attainable, single-photon FCS can be a useful technique for measuring probe diffusivity in optically dense media.
Aerodynamic Loading and Magnetic Bearing Controller Robustness Using a Gain-Scheduled Kalman Filter

Modeling or predicting aerodynamic loading effects on rotating equipment has been a source of concern to those who wish to examine stability or response of critical components. The rotordynamic model of the system employed for such examination assumes greater importance for active bearings than for passive ones, if only because of the additional potential for instability introduced by the controller. For many systems, aerodynamic loading may vary widely over the range of operation of the bearings, and may depend on extended system variables. Thus, potential controllers for active magnetic bearings require sufficient robustness or adaptation to changes in critical aerodynamic loading parameters, as might be embodied in cross-coupled stiffness terms for compressor impellers. Furthermore, the presence of plant or measurement noise provides additional sources of complication. Here, the previous development of a nonlinear controller for a hypothetical single-stage centrifugal gas compressor is extended by comparing the compensator performance using a multivariable Luenberger observer against that of a stationary Kalman filter, both gain-scheduled for rotational speed. For the postulated system, it was found that the slower poles of the Kalman filter did not observably detract from controller convergence and stability, while predictably smoothing out the simulated sensor noise.
Abstract 4773: Synergistic effects of chitosan and docosahexanoic acid on osteopontin expression and secretion in an ovarian cancer cell line, SKOV-3

Proceedings: AACR 103rd Annual Meeting 2012‐‐ Mar 31‐Apr 4, 2012; Chicago, IL Current treatment for the deadliest gynecological disease, ovarian cancer, is surgical debulking followed by chemotherapy or radiotherapy, but reoccurrence is still significantly high. Hence, there is a need for alternative treatments, and more specifically a natural therapeutic product. Recent studies have shown that natural products, such as chitosan and omega-3 fatty acids, inhibit the proliferation of cancer cells. Osteopontin (OPN), a cell surface and secretory glycoprotein, has been implicated as an important biomarker for ovarian cancer. Therefore, the objective of this study was to determine the effect of chitosan and DHA on OPN secretion and expression levels in an ovarian cancer cell line, SKOV-3 cells. We hypothesized that chitosan and DHA will decrease OPN expression in a dose-dependent manner. To test our hypothesis, SKOV-3 cells were treated with (a) 0 ng/mL, (b) 1% acetic acid; (c) 250 ng/mL of chitosan, (d) 100 µM of DHA, (e) 250 ng/mL of chitosan + 100 µM of DHA for 24 and 48 hours. Western Blot analysis and immunocytochemistry were performed to observe the expression and localization of OPN, while an ELISA was used to determine OPN secretion. Quantitative RT-PCR was also performed to determine OPN mRNA expression in the treated cells. Osteopontin (OPN) protein was localized on the surface of SKOV-3 cells and its expression decreased in both chitosan and DHA-treated cells. Furthermore in cells treated with both chitosan and DHA, there was an even greater decrease in OPN expression. The synergistic effects of chitosan and DHA suggest that these natural products may serve as potential natural treatment for ovarian cancer. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4773. doi:1538-7445.AM2012-4773
Generalized Wiener Filtering Computation Techniques

The classical signal processing technique known as Wiener filtering has been extended to the processing of one-and two-dimensional discrete data by digital operations with emphasis on reduction of the computational requirements. In the generalized Wiener filtering process a unitary transformation, such as the discrete Fourier, Hadamard, or Karhunen-Loeve transform is performed on the data that is assumed to be composed of additive signal and noise components. The transformed data is then modified by a filter function, and the inverse transformation is performed to obtain the discrete system output. The filter function is chosen to provide the best mean square estimate of the signal portion of the input data.
Peptide binding to MHC class I molecules: Implications for antigenic peptide prediction

The human mayor histocompatibility complex class I molecule HLA-A2 preferentially binds peptides that contain Leu at P2 and Val or Leu at the C terminus. The other amino acids in the peptide also contribute to binding positively or negatively. It is possible to estimate the binding stability of HLA-A2 complexes containing particular peptides by applying coefficients, deduced from a large amount of binding data, that quantify the relative contribution of each amino acid at each position. In this review, we describe the molecular basis for these coefficients and demonstrate that estimates of binding stability based on the coefficients are generally concordant with experimental measurements of binding affinities. Peptides that contained cysteine were predicted less well, possibly because of complications resulting from peptide dimerization and oxidation. Apparently, peptide binding affinity is largely controlled by the rate of dissociation of the HLA/peptide/beta 2-microglobulin complex, whereas the rate of formation of the complex has less impact on peptide affinity. Although peptides that bind tightly to HLA-A2, including many antigenic peptides bind much more weakly. Therefore, a full understanding of why certain peptides are immunodominant will require further research.
The effect of sodium poisoning on dealuminated Y-type zeolites

Dealuminated zeolites prepared both hydrothermally and using silicon tetrachloride were investigated to determine the effect of sodium addition on their catalytic activities. These materials were found to have drastically reduced activities upon sodium addition with each sodium atom effectively neutralizing the catalytic activity previously thought to be due to five framework Broensted acid sites. These results are interpreted to mean that isolated framework Al atoms are a necessary but insufficient condition for strong acidity, and only about one-fifth of the framework Al atoms are associated with this strong acidity. Extraframework Al is believed to impart, through inductive effects, strong acidity to these framework Broensted sites. An infrared study of the hydroxyl region revealed bands at 3,675 and 3,595-3,610 cm{sup {minus}1} ({plus minus}2 cm{sup {minus}1}) that are attributed to protons associated with different types of extraframework aluminium oxide or oxyhydroxide. A band at 3,695 cm{sup {minus}1} is attributed to Na{sup +} interacting with water which is hydrogen-bonded to a framework oxygen atom. A narrow band at 3,602 cm{sup {minus}1} is attributed to a highly acidic Broensted site in the zeolite lattice.
The fine structure of striated microtubules and sleeve bodies in several species of Anabaena

Two new inclusions in blue-green algae are described. Striated microtubules, about 0.21 μm long and 18 nm in diameter, and a wall approximately 20 A thick, were found in Anabaena minutissima. Up to 11 groups were observed in a single thin section of a cell. Sleeve bodies were observed in Anabaena cylindrica and Anabaena sp. (B-380). Each sleeve consists of a short cylinder about 32 nm in diameter. The wall of the sleeve is about 20 A thick with osmiophilic striations perpendicular to the longitudinal axis of the sleeve. An osmiophilic rod-like body, 25 nm in diameter, was found inside the sleeve. Up to seven groups of sleeve bodies were observed in a single cross section of a cell. These two inclusions are compared to gas vesicles. Various reports on structures resembling microtubules in other prokaryotes are also discussed.
Learning in an isolated prothoracic insect ganglion

Abstract 1. 1. The capacity of the isolated prothoracic ganglion to learn was investigated in adult male cockroaches, Periplaneta americana. The head was removed and the posterior connectives of the prothoracic ganglion were severed. Such a ‘miniature’ system was found capable of demonstrating avoidance learning. 2. 2. The avoidance response could be achieved by a number of different leg positions and appeared to be maintained by proprioceptive feedback. The predominant avoidance response involved flexion of the coxal-trochanter joint accompanied by tibial extension. 3. 3. In an additional group of animals the prothoracic ganglion was removed and they were given the same training and testing procedures as those with an isolated prothoracic ganglion. The results showed that long-term generalized excitability changes could occur from the effects of the shock on the peripheral neuromuscular apparatus itself. The response however was quite stereoptyped and showed none of the complexity seen in those with an intact isolated prothoracic ganglion. No P-R difference was obtained.
Crystal structure of zinc citrate

Abstract The crystal structure of zinc citrate [Zn(II) (C 6 H 5 O 7 ) 2 ·4NH 4 + ] shows isolated zinc ions octahedrally coordinated to two equivalent citrates via a central hydroxyl, central carboxyl, and one terminal carboxyl from each citrate. The clusters are linked through hydrogen bonds to ammonium ions in the lattice. The structure is distinctly different from that of other divalent cation triply ionized citrate complexes, which are polymeric. Crystal data : space group P 2 1 / C , a = 8.784(3) A, b = 13.499(4) A, c = 9.083(3) A, β = 113.4°(1), V = 988(1) A 3 . Citrate has been identified as the low molecular weight ligand that complexes zinc in human milk; this may be of interest in relation to intestinal zinc absorption.
Flashbulb memories of the assassination attempt on President Reagan

Abstract People often have vivid recollections of their own personal circumstances when first learning about attacks on major public figures. Brown and Kulik (1977) propose that these ‘flashbulb memories’ are triggered both by surprise and perceived consequentiality of the event, and are elaborated through retellings. In this study, memories of the 1981 assassination attempt on President Reagan were obtained on questionnaires completed one and seven months after the shooting. Subjects responded either at one or both time periods. Most respondents reported flashbulb memories, despite a low incidence of reported rehearsal and low consequentiality ratings. Stronger initial emotional reactions are associated with greater memory elaboration seven months after the event, while frequency of rehearsal is influential at this time only for subjects who completed an earlier questionnaire. Neither affective reactions nor rehearsal predicts memory elaboration after one month. People reacting strongly to the attack are more likely to have visual and nonvisual sensory memories at both time periods. Memories of subjects who responded to both questionnaires are highly consistent over the six-month interval. Stronger emotional reactions to the event, and not rehearsal, are associated with greater consistency of narrative and visual memories. The results suggest that intensity of initial affective reactions, rather than perceived consequentiality or rehearsal, is a primary determinant of flashback memories. A flashback mechanism is proposed to account for affectively cued recall of episodic memories.
Effect of nonparabolicity on the conduction-electron spin resonance in cubic semiconductors

The spin-resonance amplitude of conduction electrons in a cubic crystal has been calculated keeping terms up to fourth order in the wave vector k in the 2\ifmmode\times\else\texttimes\fi{}2 effective-mass Hamiltonian. Apart from corrections to the magnetic dipole amplitude, we find that the terms ${\ensuremath{\gamma}}_{0}$${\ensuremath{\mu}}_{B}$(${\ensuremath{\sigma}}_{x}$${B}_{0x}$${k}_{x}^{2}$ +${\ensuremath{\sigma}}_{y}$${B}_{0y}$${k}_{y}^{2}$+${\ensuremath{\sigma}}_{z}$${B}_{0z}$${k}_{z}^{2}$) and g''${\ensuremath{\mu}}_{B}${\ensuremath{\sigma}\ensuremath{\cdot}k, ${\mathrm{B}}_{0}$\ensuremath{\cdot}k} yield electric dipole amplitudes proportional to k\ensuremath{\cdot}${\mathrm{B}}_{0}$. While in the ordinary Voigt and cyclotron-resonance-active Faraday configurations only the ${\ensuremath{\gamma}}_{0}$ term is effective, in the cyclotron-resonance-inactive Faraday configuration both the ${\ensuremath{\gamma}}_{0}$ and g'' terms contribute. We have calculated the angular dependence of the ${\ensuremath{\gamma}}_{0}$ amplitude for arbitrary crystal orientations, the g'' amplitude being isotropic. In narrow-band-gap materials the admixture of hole states into the electron eigenstates also contributes an isotropic electric dipole spin-flip amplitude proportional to k\ensuremath{\cdot}${\mathrm{B}}_{0}$, which is distinct from those mentioned.
Effects of heating rate and hydrogen flow rate on magnetic induction and final grain texture of 3 pct silicon steel

In inhibitor-free 3 pct silicon steel of 0.1-mm thickness, magnetic induction after final annealing decreased roughly with increasing heating rate and hydrogen flow rate. This is mainly due to the increase in the number of the {110}〈uvw〉≠〈001〉 grains.
SUM FREQUENCY GENERATION INVESTIGATION OF GLYCEROL/WATER SURFACES

The OH and CH regions of glycerol/water mixtures in the concentration range 0.0−1.0 mole fraction have been investigated with vibrational sum frequency generation. Glycerol is found to partition to the surface of these solutions in all concentrations. Neat glycerol surfaces contain no free OH groups projecting into the vapor. The surface orientation of glycerol is constant through most of the concentration range.
Subchronic administration of l-DOPA to adult rats with a unilateral 6-hydroxydopamine lesion of dopamine neurons results in a sensitization of enhanced GABA release in the substantia nigra, pars reticulata

L-DOPA is the most effective pharmacological agent used for the symptomatic treatment of Parkinson's disease but long-term L-DOPA treatment induces involuntary abnormal movements such as dyskinesias. The present study, using in vivo microdialysis, investigated the effects of a single or subchronic administration of L-DOPA to adult rats with a unilateral 6-OHDA lesion of dopamine neurons on GABA release in the substantia nigra, pars reticulata (SNr). The results indicate that a challenge injection of L-DOPA (50 mg/kg, i.p.) significantly increases GABA levels in the SNr of rats treated with a daily repeated administration of L-DOPA (50 mg/kg, i.p.). Further statistical analysis between groups also showed that extracellular GABA levels were significantly higher in the subchronic L-DOPA group than in the group receiving only one injection of L-DOPA. These results show that the subchronic administration of L-DOPA results in a sensitization of enhanced extracellular GABA levels in the SNr.
On the Structural Chemistry of γ‐Brasses: Two Different Interpenetrating Networks in Ternary F‐Cell Pd–Zn–Al Phases

Novel ternary phases, (Pd(1-x)Zn(x))(18)(Zn(1-y)Al(y))(86-delta) (0<or=x<or=0.162, 0.056</=y<or=0.088, 0<or=delta<or=4), which adopt a superstructure of the gamma-brass type (called gamma'-brass), have been synthesized from the elements at 1120 K. Single-crystal X-ray structural analysis reveals a phase width (F43m, a=18.0700(3)-18.1600(2) A, Pearson symbols cF400-cF416), which is associated with structural disorder based on both vacancies as well as mixed site occupancies. These structures are constructed of four independent 26-atom gamma-clusters per primitive unit cells and centered at the four special positions A (0, 0, 0), B (1/4, 1/4, 1/4), C (1/2, 1/2, 1/2) and D (3/4, 3/4, 3/4). Two of these, centered at B and C, are completely ordered Pd(4)Zn(22) clusters, whereas the other two, centered at A and D, contain all structural disorder in the system. According to our single-crystal X-ray results, Al substitutions are restricted to the A- and D-centered clusters. Moreover, the outer tetrahedron (OT) site of the 26-atom cluster at D is completely vacant at the Al-rich boundary of these phases. Electronic structure calculations, using the tight-binding linear muffin-tin orbital atomic-spheres approximation (TB-LMTO-ASA) method, on models of these new, ternary gamma'-brass phases indicate that the observed chemical compositions and atomic distributions lead to the presence of a pseudogap at the Fermi level in the electronic density of states curves, which is consistent with the Hume-Rothery interpretation of gamma-brasses, in general.
Association between serotonin transporter gene promoter polymorphism and suicide: results of a meta-analysis.

Abstract Background There is strong evidence supporting a role for serotonin system dysfunction in the pathology of suicidal behavior. Many studies have examined the association between a functional polymorphism of the serotonin transporter gene promoter (5-HTTLPR) and suicide but have yielded inconsistent results. Our goal here, by analyzing the cumulative data from primary literature, was to determine conclusively whether there is an association. Methods Three meta-analyses were performed. One compared the 5-HTTLPR polymorphism between suicidal subjects and normal control subjects; another compared suicide attempters with nonattempters of the same psychiatric diagnoses; the last one compared either violent or nonviolent suicidal subjects with normal control subjects. Results We found no association between 5-HTTLPR polymorphism and suicidal behavior ( p = .379). When we compared subjects with the same psychiatric diagnoses, the genotypes carrying the s allele were significantly more frequent in suicide attempters than in nonattempters ( p = .004). In addition, the s allele was associated with violent suicide ( p = .0001) but not with nonviolent suicide ( p = 1.00). Conclusions Our results provide significant evidence supporting the association of the s allele of 5-HTTLPR polymorphism with suicidal behavior in the psychiatric population, also with violent suicide. These support a role for decreased serotonin transporter function in the vulnerability to suicide in a select population.
Anatomical, biomechanical, and practical considerations in posterior occipitocervical instrumentation.

Abstract Background context Patients with cervical myelopathy secondary to craniocervical instability commonly present with spinal cord compression secondary to a combination of static forces and gross instability. Craniocervical arthrodesis is therefore indicated in the treatment of the majority of these conditions. In order to facilitate arthrodesis, techniques for occipitocervical instrumentation have been developed. Purpose To systematically review the anatomy, biomechanics, and practical considerations involved in posterior occipitocervical instrumentation. Study design Retrospective literature review. Patient sample Not applicable. Outcome measures Not applicable. Methods Retrospective literature review. Results The anatomic elements of the craniocervical junction include the occipital bone, occipital condyles, atlas (C1), and axis (C2). The occiput–C1 and C1–C2 motion segments possess unique mechanical properties. Occipitocervical instrumentation constructs are comprised of points of fixation and longitudinal elements, each with characteristic strengths and weaknesses. Conclusions Analysis of the anatomy, available points of fixation, and the movements to be controlled leads to the choice of a longitudinal element which can control movement by incorporating the strongest points of fixation. By going through this process for each patient, an informed decision may be made regarding the optimal occipitocervical instrumentation construct.
Climatic and paleogeographic significance of eolian sediment in the Middle Permian Dog Creek Shale (Midcontinent U.S.)

Abstract Middle Permian fine-grained redbeds of Midcontinent North America are analogous to many Permian units globally. They archive an interesting time in Earth history, but the lack of fossils and the fine grain size have confounded attempts to refine the age and depositional setting, respectively. Here we focus on the Dog Creek Shale and correlatives of Oklahoma and Kansas (paleo-tropical western Pangaea), which are representative of many analogous Permian units across the region and globe, to assess the age, depositional environment, and provenance of siliciclastic material. These mudstone-dominant units have long been interpreted to record marine deltaic or tidal flat deposition based primarily on the presence of evaporites and an inferred relationship with sandstone units southward. However, the uniform grain size, and occurrence of common paleosols, together with the lack of typical deltaic attributes such as hyper/hypo-pycnites, proximal deltaic channels, and large-scale upwardly coarsening trends, in addition to the problematic correlation, complicate this interpretation. Sheet-like tabular siliciclastic units thin northward from the Anadarko foredeep (Oklahoma) onto the Anadarko shelf (Kansas), and undergo lateral facies changes into marginal marine evaporites of the San Andres Formation in the Palo Duro Basin (Texas Panhandle). The fine and uniform grain size, massive bedding, and sheet-like geometry indicate that the siliciclastic units are eolian in origin, but at times were transported by wind and deposited and reworked in mudflats. Abundant Vertisols within the Dog Creek Shale indicate periods of wetting and drying in a low-relief setting. Major detrital zircon age populations reflect a dominantly east to southeasterly Appalachian–Ouachita source, with minor input from derivative sediment from the Ancestral Rocky Mountains to the west and northwest. These data indicate prevailing easterlies, and some westerly and southwesterly winds in western equatorial Pangaea, possibly representing north to south shifting of the Inter-Tropical Convergence Zone (ITCZ), likely associated with monsoonal circulation. The predominance of eolian-transported material and its capture in a series of mudflats and soils indicates that midcontinent North America (western equatorial Pangaea) formed a major sink for large volumes of atmospheric dust in middle Permian time, quite unlike the modern and recent tropics.
Stripping analysis of zinc in natural waters utilizing the medium exchange method

Abstract Stripping analysis with medium exchange is employed for the flow analysis of zinc in natural waters. In order to minimize the interference due to the hydrogen evolution current, that masks the zinc peak in analysis of acidified natural waters, more suitable electrolyte is transferred (following the deposition step) into the detector. A flow cell with a stationary mercury film disk electrode is employed. Measurements can be performed in the presence of oxygen in the sample solution, utilizing an oxygen free exchange solution.