cssi/SciSciGPT-SciSciNet huggingface dataset:
Endpoints and Analyses to Discern Disease-Modifying Drug Effects in Early Parkinson’s Disease

Parkinson’s disease is an age-related degenerative disorder of the central nervous system that often impairs the sufferer’s motor skills and speech, as well as other functions. Symptoms can include tremor, stiffness, slowness of movement, and impaired balance. An estimated four million people worldwide suffer from the disease, which usually affects people over the age of 60. Presently, there is no precedent for approving any drug as having a modifying effect (i.e., slowing or delaying) for disease progression of Parkinson’s disease. Clinical trial designs such as delayed start and withdrawal are being proposed to discern symptomatic and protective effects. The current work focused on understanding the features of delayed start design using prior knowledge from published and data submitted to US Food and Drug Administration (US FDA) as part of drug approval or protocol evaluation. Clinical trial simulations were conducted to evaluate the false-positive rate, power under a new statistical analysis methodology, and various scenarios leading to patient discontinuations from clinical trials. The outcome of this work is part of the ongoing discussion between the US FDA and the pharmaceutical industry on the standards required for demonstrating disease-modifying effect using delayed start design.
1,2-Dipalmitoyl-sn-glycero-3-phosphocholine (DPPC)-Rich Domain Formation in Binary Phospholipid Vesicle Membranes: Two-Dimensional Nucleation and Growth

Decades of study have probed phase transitions in model phospholipid bilayers and vesicles, especially in the context of the equilibrium phase diagram. Critical to the response of vesicles to environmental triggers, to the ultimate domain morphology, and to the approach to equilibrium (or not), we present here a study of domain formation in vesicles, focusing on a mechanism by which the cooling rate, tension, and composition affect the first appearance (nucleation) and subsequent growth of solid membrane domains. Employing a popular mixed membrane model based on DOPC and DPPC (1,2-dioleoyl-sn-glycero-3-phosphocholine and 1,2-dipalmitoyl-sn-glycero-3-phosphocholine, respectively), we examined phase separation in giant two-component vesicles that were cooled from the one-phase fluid (Lα) region of the phase diagram into a region of fluid (Lα)-solid coexistence. At moderate and low membrane tensions, cooling produced solid DPPC-rich domains appearing as compact patches or irregular hexagons and likely with a Pβ' (ripple) arrangement. (The compact solid domains in this study differed distinctly from striped domains in vesicles of the same composition, in terms of molecular organization and conditions of first appearance during cooling.) The amounts of these solid domains were shown to adhere to the lever arm rule for a tie line on the phase diagram, with a solid composition near 95 mol % DPPC. The nucleation of the compact solid domains occurred in a short period, followed by rapid addition of ordered molecules to the nucleated domains, excluding tracer dye. The two-dimensional nucleation density of these compact solid domains (in the range of 10(-2)-10(-1) μm(-2)) was found to increase with the cooling rate (equivalent to the quench depth) with a greater than linear dependence. The 2-D nucleation density was also seen to decrease with membrane tension, presumably because membrane tension increases the line tension around a domain that opposes nucleation. A sigmoidal dependence of the nucleation density on the DPPC concentration was also found. With cooling rates in excess of ∼1 °C/min, solid domains persisted down to room temperature, likely passing from a preferred equilibrium to a local equilibrium with continued cooling. As a result of the persistence of the originally nucleated domains and the conservation of DPPC in the membrane, we observed an increasingly greater number of smaller domains with increased cooling rates. The domains in these vesicles were compact or hexagonal-shaped in contrast to flower-shaped dendritic domains in the same membrane system in a supported membrane configuration.
Confinement and Light-Front QCD

Numerical results for the (rest-frame) $Q\bar{Q}$ potential in light-front quantized $QCD_{2+1}$ on a $\perp$ lattice are presented. Both in the longitudinal as well as the $\perp$ spatial directions one obtains linear confinement. The confinement mechanism in light-front QCD depends on the orientation of the external charges: for longitudinally (with respect to the boost direction in the infinite momentum frame) separated quarks, confinement arises from the instantaneous interaction piece in the Hamiltonian while for $\perp$ separated quarks, the confinement mechanism is similar to the one in Hamiltonian lattice QCD. Nevertheless, already a very simple ansatz for the effective link-field potential yields an almost rotationally symmetric $Q\bar{Q}$ potential. The momentum carried by the glue strongly depends on the orientation ("polarization") of the $Q\bar{Q}$ pair.
Experimental hyperplasia of the stomach mucosa.

Summary and ConclusionAn increase in number of parietal cells occurs in the mucosa of the guinea pig stomach after protracted stimulation with histamine over a period of 2 to 4 weeks. This is presumably a hyperplasia and may indicate a mechanism to explain differences in the number of secreting cells in different human stomachs.
Ethnicity and Aborlglnality: Case Studies in Ethnonationalism

Ethnicity and Aborlglnality: Case Studies in Ethnonationalism. MICHAEL D. LEVIN, ed. Toronto: University of Toronto Press, 1993. xiii +179 pp., contributors.
Transition from quasiperiodicity to chaos for three coaxial vortex rings

The dynamics of three coaxial vortex rings of strengths Γ 1 , Γ 2 and Γ 3 in an ideal fluid is investigated. It is proved that if rj, rj + Γ k and Γ 1 + Γ 2 + Γ 3 are not zero for all j, k = 1, 2, 3, then KAM and Poincare-Birkhoff theory can be used to prove that if the distances among the rings are sufficiently small compared to the mean radius of the rings, there are many initial configurations of the rings that produce quasiperiodic or periodic motions. Moreover, it is shown that the motion become chaotic as the inter-ring distances are increased relative to the mean radius.
Binding of Aβ Monomer to DMPC Bilayer using Isobaric-Isothermal Replica Exchange Molecular Dynamics

Interactions between Aβ peptides and cellular membranes have been implicated as a possible cause of the cytotoxicity associated with Alzheimer's disease; however, little is known about the molecular mechanisms predominating Aβ and lipid bilayer interactions. To understand Aβ-lipid interactions at molecular level, we have performed all-atom explicit solvent replica exchange molecular dynamics simulations in the isobaric-isothermal ensemble of the Aβ monomer binding to the zwitterionic DMPC bilayer. Upon binding, Aβ undergoes a dramatic structural transition from random coil state in water to a state predominated by stable helical structure in the peptide's hydrophobic C-terminal and, to a lesser extent, the central hydrophobic cluster. In addition, binding to the lipid bilayer induces the formation of the intrapeptide Asp23-Lys28 salt bridge. The peptide's C-terminal and central hydrophobic cluster do not only govern binding to the bilayer but they also penetrate into the bilayer core. In contrast, the polar N-terminal and turn region remain solvated and mainly form interactions with the bilayer surface. This partial insertion of Aβ reduces the local density of lipids and creates an indentation in the bilayer. Surprisingly, peptide insertion does not significantly distort lipid structural properties or enhance water permeation. Taken together, these results suggest that Aβ aggregation in the presence of a zwitterionic lipid bilayer is likely to be different from that in bulk water. Small structural perturbations in lipids induced by the Aβ monomer may constitute the molecular basis of its low cytotoxicity.
Type 2 diabetes management: A comprehensive clinical review of oral medications

Diabetes is a major and growing health problem in the US. An incredible array of different oral medications is now on the market. Clinicians should understand all these new medications and in which clinical picture they will work best.
Structure of α-Fe2O3 single crystal surfaces following Ar+ ion bombardment and annealing in O2

The surface stoichiometry and structure of α-Fe2O3(0001) and (10ovbar|12) natural growth faces has been studied with X-ray photoemission and LEED following room temperature Ar ion bombardment and subsequent annealing in partial pressures of O2 between 400°C and 1000°C. Disordered, oxygen-deficient ion bombardment surfaces were annealed to produce surface structures and stoichiometries approaching the ideal truncation of bulk α-Fe2O3, but only after long, high temperature annealing treatments in 10−6 Torr O2. LEED suggests that a Fe3O4(111) layer initially forms on the (0001) face for annealing temperatures up to 775°C. At higher temperatures, extra diffraction beams are observed which are attributed to multiple scattering across a Fe1−xO(111)/α-Fe2O3(0001) interface. The extra beams disappear after long annealing times at 900°C and are replaced by a (1 × 1) pattern characteristic of α-Fe2O3(0001). On the (10ovbar|12) surface, a (1 × 1) LEED pattern is observed when the surface is annealed in 10−6 Torr O2, but a (1 × 2) reconstruction similar to that observed on the surface of α-Al2O3 is evident in lower O2 partial pressures. The surface phases produced by ion bombardment and annealing treatments are quite different from those predicted by the bulk FeO phase diagram.
An Ocean Dynamical Thermostat

Abstract The role of ocean dynamics in the regulation of tropical sea surface temperatures (SSTs) is investigated using the Zebiak-Cane coupled occan-atmosphere model. The model is forced with a uniform heating, or cooling, varying between ±40 W m−2 into the ocean surface. A new climatological SST pattern is established for which the area-averaged temperature change is smaller in magnitude than the imposed forcing. The forcing is balanced almost equally by a change in the heat flux out of the ocean and by vertical advection of heat in the ocean through anomalous equatorial ocean upwelling. The generation of anomalous upwelling is identified here as a possible mechanism capable of regulating tropical SSTS. This ocean dynamical thermostat mechanism has, a seasonally varying efficiency that causes amplification (weakening) of the seasonal cycle for the heating (cooling). The interannual variability also changes under the imposed forcing. These results suggest that the role of ocean dynamic should he included...
Residual compression in area array packages induced by underfill shrinkage

Abstract A non-linear finite element model is developed to investigate underfill shrinkage as a possible source for obtaining beneficial residual compression in solder grid array interconnects. The axisymmetrical model geometry consists of a unit cell of concentric cylinders, the inner with properties representative of solder and the outer with properties representative of underfill, having an outer radius of half the array pitch. The solder, which is assumed to be eutectic, is modeled as an elastic–plastic material that exhibits creep behavior. The elastic modulus and Poisson’s ratio of the underfill material, Eu and νu, as well as the percentage of unconstrained linear shrinkage, ϕ, are varied to determine the influence these parameters have on the final steady-state stresses in the solder connections. To represent the underfill materials in common use, Eu ranged from 0.5 to 8.0 GPa, νu ranged from 0.2 to 0.4, and ϕ ranged from 0.2% to 1.0%. Upon shrinkage of the underfill during curing, the model predicts that the interconnect initially experiences residual compression in the axial direction. Due to tension in the radial direction, however, creep strain causes the axial compressive stress to lessen until a state of hydrostatic stress is reached. For the underfill properties tested, all the residual, steady-state stresses were compressive. The magnitude of this compression is shown in graphical form as a function of Eu, νu, and ϕ. An analytical expression for estimating the magnitude of residual compression as a function of these underfill properties is also included. The potential effect of the residual compression on the fatigue life of a package is discussed in the context of a particular example.
The current practices in food advertising

A content analysis and a quasi-experiment were performed to examine the current practices in food advertising, and the usage and the effectiveness of different advertising claims across two food categories (hedonic vs functional). The content analysis revealed that taste and specific nutrition claims are the two dominating types of advertising claims in recent food advertisements. Also, a greater proportion of advertisements for functional (vs hedonic) foods appeared to use such nutrition/health claims as general health and contains nutrient claims, whereas a greater proportion of advertisements for hedonic (vs functional) foods used taste claims. However, these current practices of food advertising were called into question by the results of the quasi-experiment, which showed that the nutrition/health claims were more effective when promoting hedonic (vs functional) foods, whereas taste claims were more effective when promoting functional (vs hedonic) foods in generating favourable attitudes and purchase...
Single port laparoscopy

Objective To demonstrate the abdominal wall anatomy necessary to perform a single port laparoscopic procedure. Single port laparoscopic (SPL) surgery has reduced the number of sites required to perform laparoscopic surgery. However, the incision at the umbilicus is larger than conventional laparoscopic surgery. Design Video presentation of clinical article. The video uses animation and surgical cases to demonstrate the relevant abdominal wall anatomy to establish surgical access for a single site or single port laparoscopy. Result(s) This video demonstrates the regional anatomy pertinent to the anterior abdominal wall, specifically of the umbilicus. The umbilicus is a focal point of fusion of the anterior abdominal wall muscles that allows entry into the peritoneal cavity. For this procedure there are 2 incisions possible, a small midline intra-umbilical one and an omega incision. The video demonstrates each technique. Introduction of a port into this single incision is demonstrated with 2 different trocar systems. These trocar systems show how the limitations of using a single site may be reduced. Conclusion(s) The abdominal wall anatomy is unique at the umbilicus and allows optimal placement of a single trocar to allow laparoscopic surgery. Video is available at http://fertstertforum.com/2012974caravalho/.
ATOMISTIC SIMULATIONS OF STRUCTURES AND MECHANICAL PROPERTIES OF POLYCRYSTALLINE DIAMOND : SYMMETRICAL (001) TILT GRAIN BOUNDARIES

Atomic structures and energies of symmetrical {l_angle}001{r_angle} tilt grain boundaries (GB{close_quote}s) in diamond have been calculated over a wide range of misorientation angle using a many-body analytic potential, and for some selected short-period grain boundaries with tight-binding and first-principles density-functional methods. The grain boundary energies from the tight-binding and first-principles methods are about 75{percent} of those calculated with the analytic bond-order potential. The energy rankings of the GB{close_quote}s calculated with the empirical potential, however, are similar to that calculated from the tight-binding and the density functional approaches. Atomic-level energy and stress distributions calculated with the bond-order potential reveal relations between local interface reconstruction and the extent and value of hydrostatic and shear stresses. From the calculated local volume strain and hydrostatic stress fields, the atomic bulk moduli are evaluated, and zones of different elastic behavior in the vicinity of the interface are defined. {copyright} {ital 1999} {ital The American Physical Society}
NMR investigations of nitrophorin 2 belt side chain effects on heme orientation and seating of native N-terminus NP2 and NP2(D1A).

Nitrophorin 2 (NP2), one of the four NO-storing and NO-releasing proteins found in the saliva of the blood-sucking bug Rhodnius prolixus, has a more ruffled heme and a high preference for a particular heme orientation (B) compared with nitrophorin 1 and nitrophorin 4, which show not a preference (A to B ratio of approximately 1:1), suggesting that it fits more tightly in the β-barrel protein. In this work we have prepared a series of “belt” mutants of NP2(D1A) and (ΔM0)NP2 aimed at reducing the size of aromatic or other residues that surround the heme, and investigated them as the high-spin aqua and low-spin N-methylimidazole complexes. The belt mutants included Y38A, Y38F, F42A, F66A, Y85A, Y85F, Y104A, I120T, and a triple mutant of NP2(D1A), the F42L, L106F, I120T mutant. Although I120 has been mainly considered to be a distal pocket residue, CδH3 of I120 lies directly above the heme 3-methyl, at 2.67 A, of heme orientation B, or the 2-vinyl of A, and it thus plays a role as a belt mutant, a role that turns out to be extremely important in creating the strong favoring of the B heme orientation [A to B ratio of 1:14 for NP2(D1A) or 1:12 for (ΔM0)NP2]. The results show that the 1D 1H NMR spectra of the high-spin forms are quite sensitive to changes in the shape of the heme binding cavity. The single mutation I120T eliminates the favorability of the B heme orientation by producing a heme A to B orientation ratio of 1:1, whereas the single mutation F42A reverses the heme orientation from an A to B ratio of 1:14 seen for NP2(D1A) to 10:1 for NP2(D1A,F42A). The most extreme ratio was found for the triple mutant of NP2(D1A), NP2(D1A,F42L,L105F,I120T), in which the A to B ratio is approximately 25:1, a ΔG change of about −3.5 kcal/mol or −14.1 kJ/mol with respect to NP2(D1A). The seating of the heme is modified as well in that mutant and in several others, by rotations of the heme by up to 4° from the seating observed in NP2(D1A), in order to relieve steric interactions between a vinyl β-carbon and a protein side chain, or to fill a cavity created by replacing a large protein side chain by a much smaller one; the latter was observed for all tyrosine to alanine mutants. These relatively small changes in seating have a measurable effect on the NMR spectra of the mutants, but are indeed minor in terms of overall seating and reactivity of the NP2(D1A) protein. The 1H NMR resonances of the hemin substituents of the low-spin N-methylimidazole complexes of NP2(D1A,F42L,L105F,I120T) as well as NP2(D1A,I120T), NP2(D1A,Y104A), and NP2(D1A,F42A) have been assigned using natural abundance 1H{13C} heteronuclear multiple quantum correlation and 1H–1H nuclear Overhauser effect spectroscopy spectra.
Molecular epigenetics and genetics in neuro-oncology

Gliomas arise through genetic and epigenetic alterations of normal brain cells, although the exact cell of origin for each glioma subtype is unknown. The alteration-induced changes in gene expression and protein function allow uncontrolled cell division, tumor expansion, and infiltration into surrounding normal brain parenchyma. The genetic and epigenetic alterations are tumor subtype and tumor-grade specific. Particular alterations predict tumor aggressiveness, tumor response to therapy, and patient survival. Genetic alterations include deletion, gain, amplification, mutation, and translocation, which result in oncogene activation and tumor suppressor gene inactivation, or in some instances the alterations may simply be a consequence of tumorigenesis. Epigenetic alterations in brain tumors include CpG island hypermethylation associated with tumor suppressor gene silencing, gene-specific hypomethylation associated with aberrant gene activation, and genome-wide hypomethylation potentially leading to loss of imprinting, chromosomal instability, and cellular hyperproliferation. Other epigenetic alterations, such as changes in the position of histone variants and changes in histone modifications are also likely to be important in the molecular pathology of brain tumors. Given that histone deacetylases are targets for drugs that are already in clinical trial, surprisingly little is known about histone acetylation in primary brain tumors. Although a majority of epigenetic alterations are independent of genetic alterations, there is interaction on specific genes, signaling pathways and within chromosomal domains. Next-generation sequencing technology is now the method of choice for genomic and epigenome profiling, allowing more comprehensive understanding of genetic and epigenetic contributions to tumorigenesis in the brain.
The effect of clofibrate on vitamin E concentrations in the rat

Abstract Clofibrate treatment was associated with a decrease in serum tocopherol levels in the rat. Adrenal and liver tissue concentrations did not change.
Methodological aspects of time-course measurements of 14C fixation in marine phytoplankton

A series of time-course studies were made in conjunction with productivity measurements to determine: (1) the time required for purging sorbed H14CO3− from glass fiber filters, (2) the duration of linearity in H14CO3− uptake in several oceanic environments, and (3) the time required for an “equilibrium” to be established among solvent-extractable and particulate fractions of natural phytoplankton populations. Acidification of sorbed H14CO3− on Whatman GFF filters requires a 60-min period before the sorbed label is reduced to background levels. Time course measurements of H14CO3− fixation in three regions of the northwestern Atlantic (two warm-core rings and the Sargasso Sea) indicated that carbon uptake was linear for at least 4–6 h. The distribution of 14C among various soluble and particulate fractions of labelled natural phytoplankton populations showed that an “equilibrium” was achieved among the various fractions after 1 to 2 h of incubation.
Holocene sedimentation of a wave-dominated barrierisland shoreline: Cape Lookout, North Carolina

Abstract The sedimentary record of 130 km of microtidal (0.9 m tidal range) high wave energy (1.5 m average wave height) barrier island shoreline of the Cape Lookout cuspate foreland has been evaluated through examination of 3136 m of subsurface samples from closely spaced drill holes. Holocene sedimentation and coastal evolution has been a function of five major depositional processes: (1) eustatic sea-level rise and barrier-shoreline transgression; (2) lateral tidal inlet migration and reworking of barrier island deposits; (3) shoreface sedimentation and local barrier progradation; (4) storm washover deposition with infilling of shallow lagoons; and (5) flood-tidal delta sedimentation in back-barrier environments. Twenty-five radiocarbon dates of subsurface peat and shell material from the Cape Lookout area are the basis for a late Holocene sea-level curve. From 9000 to 4000 B.P. eustatic sea level rose rapidly, resulting in landward migration of both barrier limbs of the cuspate foreland. A decline in the rate of sea-level rise since 4000 B.P. resulted in relative shoreline stabilization and deposition of contrasting coastal sedimentary sequences. The higher energy, storm-dominated northeast barrier limb (Core and Portsmouth Banks) has migrated landward producing a transgressive sequence of coarse-grained, horizontally bedded washover sands overlying burrowed to laminated back-barrier and lagoonal silty sands. Locally, ephemeral tidal inlets have reworked the transgressive barrier sequence depositing fining-upward spit platform and channel-fill sequences of cross-bedded, pebble gravel to fine sand and shell. Shoreface sedimentation along a portion of the lower energy, northwest barrier limb (Bogue Banks) has resulted in shoreline progradation and deposition of a coarsening-up sequence of burrowed to cross-bedded and laminated, fine-grained shoreface and foreshore sands. In contrast, the adjacent barrier island (Shackleford Banks) consists almost totally of inlet-fill sediments deposited by lateral tidal inlet migration. Holocene sediments in the shallow lagoons behind the barriers are 5–8 m thick fining-up sequences of interbedded burrowed, rooted and laminated flood-tidal delta, salt marsh, and washover sands, silts and clays. While barrier island sequences are generally 10 m in thickness, inlet-fill sequence may be as much as 25 m thick and comprise an average of 35% of the Holocene sedimentary deposits. Tidal inlet-fill, back-barrier (including flood-tidal delta) and shoreface deposits are the most highly preservable facies in the wave-dominated barrier-shoreline setting. In the Cape Lookout cuspate foreland, these three facies account for over 80% of the sedimentary deposits preserved beneath the barriers. Foreshore, spit platform and overwash facies account for the remaining 20%.
A simple micro method for the direct determination of delta-amino (14C) levulinic acid production in murine spleen and liver homogenates.

Abstract 1. 1. A simple and sensitive radiochemical procedure for the estimation of the activity of δ-aminolevulinate synthetase (succinyl-CoA: glycine succinyltransferase) in homogenates of normal murine spleen and liver is described. 2. 2. Homogenates of spleen or liver are incubated with α- keto [ 14 C] glutarate or [14C]succinate respectively, and the [14-amino14Clevulinic acid generated in the reaction is selectively adsorbed onto a Dowex 50 column run at pH 3.9. Since labeled α-amino acids and unreacted radioactive substrate are not reatained by the column, contamination of α-aminolevulinic acid by these substances does. δ- Amino- [ 14 C] levulinic can be recovered in yields of 97–100%. 3. 3. Maximal δ- amino[ 14 C]levulinic acid production was obtainedin spleen homogenates in the presence of α- keto[ 14 C]glutarate , glycine, EDTA, and pyridoxal phosphate. δ- Amino[ 14 C]leculinic acid utilization was minimal at homogenate concentrations of 2.5% or less. Varying degrees of inhibition of δ-amino14Clevulinic acid production were seen with malate, malonate, arsenite, ATP, CoA, and NAD+. 4. 4. [14]Succinate, glycine, EDTA, and pyridoxal phosphate produced the highest levels of δ- amino[ 14 C]levulinic acid in liver homogenates. δ- Amino[ 14 C]levulinic acid utilization was minimal at homogenate concentrations of 1% or less. Varying degrees of inhibition of δ- amino[ 14 ]levulinic acid production were seen with malate, malonate, arsenite, ATP, and CoA. 5. 5. The sensitivity of the procedure will allow the measurement of δ-amino-levulinate synthetase activity in normal spleen and liver and will permit more detailed investigation of mechanisms controlling heme synthesis. Smaller amounts of tissues can be used than have been previously employed by colorimetric methods. The method can be easily adapted to preparations of mitochondria and blood cells.
Skeletal effects of long-term caloric restriction in rhesus monkeys

Age-related bone loss is well established in humans and is known to occur in nonhuman primates. There is little information, however, on the effect of dietary interventions, such as caloric restriction (CR), on age-related bone loss. This study examined the effects of long-term, moderate CR on skeletal parameters in rhesus monkeys. Thirty adult male rhesus monkeys were subjected to either a restricted (R, n = 15) or control (C, n = 15) diet for 20 years and examined throughout for body composition and biochemical markers of bone turnover. Total body, spine, and radius bone mass and density were assessed by dual-energy X-ray absorptiometry. Assessment of biochemical markers of bone turnover included circulating serum levels of osteocalcin, carboxyterminal telopeptide of type I collagen, cross-linked aminoterminal telopeptide of type I collagen, parathyroid hormone, and 25(OH)vitamin D. Overall, we found that bone mass and density declined over time with generally higher levels in C compared to R animals. Circulating serum markers of bone turnover were not different between C and R with nonsignficant diet-by-time interactions. We believe the lower bone mass in R animals reflects the smaller body size and not pathological osteopenia.
Introduction to the Aquaculture-Themed Issue

Jesse TrushenskiJim BowkerWelcome, readers, to the first in a series of themed issues for Fisheries magazine. Periodically, the Society will focus its attention on timely topics or subjects of spec...
A lipid raft environment enhances Lyn kinase activity by protecting the active site tyrosine from dephosphorylation.

The plasma membrane contains ordered lipid domains, commonly called lipid rafts, enriched in cholesterol, sphingolipids, and certain signaling proteins. Lipid rafts play a structural role in signal initiation by the high affinity receptor for IgE. Cross-linking of IgE-receptor complexes by antigen causes their coalescence with lipid rafts, where they are phosphorylated by the Src family tyrosine kinase, Lyn. To understand how lipid rafts participate in functional coupling between Lyn and FcϵRI, we investigated whether the lipid raft environment influences the specific activity of Lyn. We used differential detergent solubility and sucrose gradient fractionation to isolate Lyn from raft and nonraft regions of the plasma membrane in the presence or absence of tyrosine phosphatase inhibitors. We show that Lyn recovered from lipid rafts has a substantially higher specific activity than Lyn from nonraft environments. Furthermore, this higher specific activity correlates with increased tyrosine phosphorylation at the active site loop of the kinase domain. Based on these results, we propose that lipid rafts exclude a phosphatase that negatively regulates Lyn kinase activity by constitutive dephosphorylation of the kinase domain tyrosine residue of Lyn. In this model, cross-linking of FcϵRI promotes its proximity to active Lyn in a lipid raft environment.
Single Particle Image Reconstruction of the Human Recombinant Kv2.1 Channel

Kv2.1 channels are widely expressed in neuronal and endocrine cells and generate slowly activating K+ currents, which contribute to repolarization in these cells. Kv2.1 is expressed at high levels in the mammalian brain and is a major component of the delayed rectifier current in the hippocampus. In addition, Kv2.1 channels have been implicated in the regulation of membrane repolarization, cytoplasmic calcium levels, and insulin secretion in pancreatic beta-cells. They are therefore an important drug target for the treatment of Type II diabetes mellitus. We used electron microscopy and single particle image analysis to derive a three-dimensional density map of recombinant human Kv2.1. The tetrameric channel is egg-shaped with a diameter of approximately 80 A and a long axis of approximately 120 A. Comparison to known crystal structures of homologous domains allowed us to infer the location of the cytoplasmic and transmembrane assemblies. There is a very good fit of the Kv1.2 crystal structure to the assigned transmembrane assembly of Kv2.1. In other low-resolution maps of K+ channels, the cytoplasmic N-terminal and transmembrane domains form separate rings of density. In contrast, Kv2.1 displays contiguous density that connects the rings, such that there are no large windows between the channel interior and the cytoplasmic space. The crystal structure of KcsA is thought to be in a closed conformation, and the good fit of the KcsA crystal structure to the Kv2.1 map suggests that our preparations of Kv2.1 may also represent a closed conformation. Substantial cytoplasmic density is closely associated with the T1 tetramerization domain and is ascribed to the approximately 184 kDa C-terminal regulatory domains within each tetramer.
CRENATICAULIS, A NEW GENUS OF DEVONIAN PLANTS ALLIED TO ZOSTEROPHYLLUM, AND ITS BEARING ON THE CLASSIFICATION OF EARLY LAND PLANTS'

A B S T R A C T The name Crenaticaulis verruculosus is proposed for slender, pseudomonopodially and dichotomously branching plants that bore opposite to subopposite sporangia along the stem and two rows of prominent, multicellular teeth on opposite sides of the terete axis. Epidermal cells were either narrow and elongate parallel to the stem or short with a papillate outer tangential wall. Axillary tubercles were present on one side of the stem near lateral branches. Some tubercles bore remnants of branches. Sporangia dehisced along their distal margins into two unequal halves. No spores were found. Occasional short lengths of stem were petrified by iron pyrite. Sections revealed a cortex consisting of four to six rows of thick-walled cells and a xylem strand. The strand was elliptical in transverse section and maturation was exarch. Tracheids were chiefly scalariform. It is suggested that the so-called axillary tubercles, known in several plants of Devonian age, were scars of rhizophores like those in the modern genus Selaginella. The plant is referred to the subdivision Zosterophyllophytina. EVER SINCE Penhallow (1892) erected the genus Zosterophyllum for slender, leafless plants with reniform sporangia aggregated into spike-like
Effect of preweaning feeding of pasteurized and nonpasteurized milk on postweaning weight gain of heifer calves on a Californian dairy

Abstract The effect of preweaning feeding of pasteurized colostrum and pasteurized waste milk on postweaning performance of dairy heifers on a dairy in the Central Valley of California was investigated as an extension of a clinical trial examining the effect of preweaning growth and morbidity on performance at weaning. Of the 150 heifer calves originally enrolled in the field trial, 115 calves (59 treatment, 56 controls) were followed to about 6 months of age, during which time their weights were measured. After weights were adjusted for several potential risk factors and effect modifiers, calves fed pasteurized colostrum and pasteurized waste milk were 3.7 kg heavier at 180 days of age than those fed nonpasteurized colostrum and nonpasteurized milk.
Toxoplasma gondii: Selective Killing of Extracellular Parasites by Oxidation Using Pyrrolidine Dithiocarbamate

Extracellular Toxoplasma parasites are sensitive to pyrrolidine dithiocarbamate (PDTC) at low micromolar concentrations. Loss of parasite viability following PDTC treatment is shown to be mediated by oxidation, which is reminiscent of PDTC killing in mammalian cells. Intracellular parasites, by contrast, are resistant to PDTC killing, although treatment does cause reversible growth arrest. In addition to the possible implications relative to the biology of the parasite, these observations suggest that PDTC could be of use in eliminating undesired extracellular parasites during assays and selections in vitro.
If you have too much data, then 'good enough' is good enough

In today's humongous database systems, clarity may be relaxed, but business needs can still be met.
Nuclear remodeling after SCNT: a contractor's nightmare

As the success rate of somatic cell nuclear transfer (SCNT) remains low, researchers are turning to the very early stages of pre-implantation development to try to improve the developmental potential of reconstructed mammalian embryos. Two recent papers highlight the role of regulated proteolysis in nuclear remodeling after SCNT. First, Gao et al. describe a rapid, programmed replacement of the somatic-type linker histone H1 inside donor-cell nuclei with an oocyte-derived homolog after SCNT, which is subsequently reversed at the time of maternal embryonic transition. Second, Zhou et al. report the first successful cloning of a rat by using selective blockers of the ubiquitin-dependent degradation of cell-cycle regulator cyclin B. Therefore, a fast, programmed proteolysis might be of central importance for nuclear remodeling after SCNT, particularly in the ubiquitin-proteasome pathway.
Intercalation and exfoliation routes to graphite nanoplatelets

Graphite nanoplatelets with thicknesses down to 2–10 nm are synthesized by alkali metal intercalation followed by ethanol exfoliation and microwave drying. Graphite that has already been intercalated and exfoliated with an oxidizing acid is reintercalated with an alkali metal to form a first stage compound, as confirmed by powder X-ray diffraction. This can be achieved either by heating graphite and potassium or caesium at 200 °C, or at room temperature using a sodium–potassium alloy. Reaction of the intercalated graphite with ethanol causes exfoliation of the graphene layers. Microwave radiation aids in drying and results in further separation of the sheets. Thermogravimetric analysis indicates that the graphite nanoplatelets are approximately 150 °C less stable in air than pristine graphite. High aspect ratio graphite nanoplatelets offer promise as reinforcements for high strength carbon–carbon composites.
Seed size effects on growth and N2 fixation of juvenile sainfoin

Abstract Seed size of forage legumes influences seedling establishment and vigor. Two studies were conducted to examine the effects of seed size on growth and N 2 fixation of juvenile sainfoin ( Onobrychis viciifolia Scop.). In two growth chamber experiments, ‘Remont’ sainfoin was evaluated for nodulation, plant height, dry matter yield, N concentration, and acetylene reduction activity (ARA). Seedlings from large seed emerged faster, had more nodules, and had higher N 2 fixation rates at most harvest dates up to 84 d. Across all harvests, seed size accounted for 60, 81, 87, 90, and 98% of the variability in mean ARA, nodule number, total plant N content, plant dry weight, and plant height, respectively. The superiority of seedlings from large seed was not due to increased relative growth rates. Two Remont seed lots that differed in seed weight distributions had similar ARA and shoot dry weight patterns, but varied in their correlations between ARA and seed size. It appears that the factors influencing seed size also affected subsequent seedling behavior of these two seed lots. Divergent individual plant selections for high or low ARA at 56, 70, or 84 d would have arisen from the largest or smallest seed size classes, respectively, if seed size effects had been ignored in a breeding program. Considerable variability for plant dry weight and ARA existed within seedlings from uniformly sized seed. We conclude that for breeding purposes, growth or ARA analyses of juvenile sainfoin should be conducted with sized seed in order to minimize seed-size effects and to better expose genetic variability in N 2 fixation.
Fermentation and Utilization of Grass Silage

The decision to utilize particular forages in support of dairy production should be based on a number of key factors, such as available land base, type of manure management, soil type and topography, climate, and availability of purchased forages and feeds. Because of the complexity and environmental concerns existing in the dairy industry today, decisions about forage and manure management should include whole farm analysis with the aid of computer software. The chemical composition and digestibility of grass are affected more by stage of maturity than by other management factors, such as species, DM, or type of harvest system. The decline in digestibility of nutrients in first growth forage is approximately .55 to .68%/d and is dependent on the method of estimation. The decline in digestible DMI in first growth is .3 to .5%/d. The use of silage additives has become an integral part of forage management, and improvements in DMI and milk production are documented. Particle size and type of harvest equipment significantly affect eating behavior and efficiency of milk production. Wilting of silage results in an increase in DMI and efficiency of microbial protein production.
Reduced pain-related behavior by adrenal medullary transplants in rats with experimental painful peripheral neuropathy

Adrenal medullary transplants in the spinal subarachnoid space, by providing a continual source of opioid peptides and catecholamines, offer a potentially important adjunct in the management of chronic pain. While previous studies have shown that this approach is effective against high-intensity phasic stimuli, adrenal medullary implants need to be evaluated against long-term and abnormal pain syndromes before transplantation can be used for human chronic pain. Using a recently developed model of painful peripheral neuropathy, the effects of adrenal medullary chromaffin cells transplanted into the subarachnoid space was evaluated. Peripheral mononeuropathy was induced by loosely tying 4 ligatures (4-0 chromic gut) around the right sciatic nerve. This procedure produces various pain symptoms including allodynia, hyperalgesia and dysesthesia. Rats were given either adrenal medullary tissue or control striated muscle transplants. Animals with adrenal medullary tissue transplants showed markedly decreased allodynia to innocuous cold as early as 1 week post-transplantation. In addition, hyperalgesia to a noxious thermal stimulus was eliminated by adrenal medullary, but not control, transplants. Touch-evoked allodynia was only slightly reduced by adrenal medullary transplants. In addition, indicators of spontaneous pain appeared reduced in animals with adrenal medullary transplants. These findings indicate that adrenal medullary transplants may be effective in reducing neuropathic pain.
Cumulus convection and the Madden-Julian oscillation of the tropical troposphere

Abstract Parameterizations of cumulus convection for use in large scale numerical models of the atmosphere are classified according to whether they are based on an energy equilibrium principle or on a balance between the supply of mass or moisture and its consumption by convection. Though some of the most popular cumulus parameterizations are based on mass or moisture balance, I argue that energy balance is a more appropriate governing principle. Physical consistency and the absence of spurious short wavelength instabilities are points in its favor. A simple energy equilibrium parameterization with a minimal representation of precipitation processes is then described, with the objective of reducing the convective parameterization problem to its essential elements. This model is first shown not to exhibit small scale instabilities. When wave-related variations in the surface entropy flux are included, it is then found (in agreement with other energy balance models) to support large scale waves similar to the observed Madden-Julian oscillation of the tropical troposphere. The characteristic period of the waves is related to the time needed for sea-air fluxes to alter the tropospheric profile of equivalent potential temperature, and their intensity and phase speed are sensitive to variations in the parameters controlling the formation and evaporation of precipitation.
Attractors for the 3D baroclinic quasi-geostrophic equations of large-scale atmosphere

Abstract The existence of absorbing sets and a compact, connected global attractor to the 3D baroclinic quasi-geostrophic equations of large scale atmosphere are obtained. Using CFT theory, an upper bound of the Hausdorff and fractal dimensions of the global attractor in terms of the physically relevant parameters Re (the Reynolds number), Ro (the Rossby number) and ¦ f ¦ is derived. Moreover, similar results are also established for the 2D vorticity equations of globe atmosphere.
Effect of Inbreeding on the Growth Curves of Height at Withers, Weight, and Heart Girth of Holstein Females

Summary By means of suitable mathematical and statistical techniques we have demonstrated a significant, proportionate per cent decrease of size in height, weight, and heart girth among the daughters of Bear Valley Ormsby Esther 518683 with increasing coefficient of inbreeding.
The effect of light soaking on the low temperature photoconductivity of hydrogenated amorphous silicon

Abstract Exposure of intrinsic and lightly doped glow discharge hydrogenated amorphous silicon to white light at an intensity of about 100 mW cm−2 for several hours (light soaking) induces changes in the temperature dependence of the photoconductivity. These changes, which can be reversed by heating to 200 °C, are different for samples with different Fermi levels E F but can in each case be explained by an increase in the density of states in the lower half of the gap. These states are different from the states 1 and 2 previously inferred from the temperature dependence of the photoconductivity. For E F near midgap, no increase in the density of dangling bonds is seen after light soaking. The behavior of slightly n-type samples can be explained by shifts of E F and the resulting changes in occupation of existing dangling bonds. In p-type samples, increased recombination probably occurs through the light-induced states, which are not dangling bonds.
Reference group influence in consumer role rehearsal narratives

Purpose – This paper aims to analyse reference group influence through the imagined audience construct of the role theory. Prior research has shown the influential nature of reference groups on an individuals’ behaviour. The studied theatrical metaphor supplies a new perspective to the social phenomenon of reference group dynamics in consumer behaviour. Design/methodology/approach – Twenty face-to-face interviews were conducted utilizing a naturalistic research study design. The interviews took place in the participants’ homes, and participants were asked to create five outfits for various social situations. Then, the participants were asked about the outfits they created, and how that outfit aided in their role preparation process. An inductive analysis of the data resulted in narrative themes that align with several role theory constructs. Findings – The consumer role rehearsal narratives that emerged describe the process individuals go through for anticipated social interactions. Depending on the socia...
Monolaurin Preparation Method Affects Activity Against Vegetative Cells ofBacillus cereus

Vegetative cells ofBacillus cereusATCC 14579 were challenged in brain heart infusion (BHI) broth with 25 μg/mL glycerol monolaurate (monolaurin) prepared by two methods: (1) water-dispersed with heat (40 °C) and agitation, or (2) dissolving in ethanol. Two inocula amounts (103and 105cfu/mL) were evaluated for survival at 25 °C over a 24-h incubation period. The 105cfu/mL inoculum was also evaluated for survival at 5 °C for 7 d. Survival ofB. cereusin BHI + 25 g/L ethanol, as a control, was also determined. Ethanol did not lower numbers ofB. cereusat 25 °C. Presence of monolaurin, regardless of preparation method, resulted in significantly lower numbers ofB. cereusat 5 or 25 °C compared to controls. Numbers in BHI + ethanol-dissolved monolaurin were significantly lower than BHI + heated, water-dispersed monolaurin for inoculum of 105cfu/mL. No differences were observed between heated treatments in a preliminary experiment comparing monolaurin (25 μg/mL) added to BHI and autoclaved, BHI + water-dispersed monolaurin (stock solution heated to 40 °C and agitated for 30 s), and BHI + water-dispersed monolaurin (stock solution heated to 70 °C and agitated for 30 min). Results show that monolaurin is more effective against vegetative cells ofB. cereuswhen dissolved in ethanol than when heat-dispersed in an aqueous system.