cssi/SciSciGPT-SciSciNet huggingface dataset:
Investigating carbon flux variability in subtropical peat soils of the Everglades using hydrogeophysical methods

The spatial and temporal variability in accumulation and release of greenhouse gases (mainly methane and carbon dioxide) to the atmosphere from peat soils remains very uncertain. The use of near-surface geophysical methods such as ground penetrating radar (GPR) has proven useful during the last decade to expand scales of measurement as related to in situ gas distribution and dynamics beyond traditional methods (i.e., gas chambers). However, this approach has focused exclusively on boreal peatlands, while no studies in subtropical systems like the Everglades using these techniques exist. In this paper GPR is combined with gas traps, time-lapse cameras, gas chromatography, and surface deformation measurements to explore biogenic gas dynamics (mainly gas buildup and release) in two locations in the Everglades. Similar to previous studies in northern peatlands, our data in the Everglades show a statistically significant correlation between the following: (1) GPR-estimated gas content and gas fluxes, (2) GPR-estimated gas content and surface deformation, and (3) atmospheric pressure and both GPR-estimated gas content and gas flux. From these results several gas-releasing events ranging between 33.8 and 718.8 mg CH4 m−2 d−1 were detected as identified by the following: (1) decreases in GPR-estimated gas content within the peat matrix, (2) increases in gas fluxes captured by gas traps and time-lapse cameras, and (3) decreases in surface deformation. Furthermore, gas-releasing events corresponded to periods of high atmospheric pressure. Changes in gas accumulation and release were attributed to differences in seasonality and peat soil type between sites. These results suggest that biogenic gas releases in the Everglades are spatially and temporarily variable. For example, flux events measured at hourly scales were up to threefold larger when compared to daily fluxes, therefore suggesting that flux measurements decline when averaged over longer time spans. This research therefore questions what the appropriate spatial and temporal scale of measurement is necessary to properly capture the dynamics of biogenic gas release in subtropical peat soils.
ESCHERICHIA COLI Gene Induction by Alkylation Treatment

ABSTRACT Searches for alkylation-inducible ( aid ) genes of Escherichia coli have been conducted by screening random fusions of the Mu-dl(Ap R lac ) phage for fusions showing increased β-galactosidase activity after treatment with methylating agents, but not after treatments with UV-irradiation. In this report we describe gene fusions that are specifically induced by alkylation treatments. Nine new mutants are described, and their properties are compared with the five mutants described previously. The total of 14 fusion mutants map at five distinct genetic loci. They can be further subdivided on the basis of their induction by methyl methanesulfonate (MMS) and N -methyl- N 9-nitro- N -nitrosoguanidine (MNNG). alkA, aidB and aidD are induced by both agents and appear to be regulated by ada . Neither aidC nor aidI is regulated by ada . Moreover, since aidC is induced only by MNNG and aidI is induced only by MMS, these two genes are likely to be individually regulated. Thus, there appear to be at least three different regulatory mechanisms controlling aid genes.
Comparison of the inhibitory effects of diverse amino acids and amino acid analogs on 12-O-tetradecanoylphorbol-13-acetate-induced ornithine decarboxylase activity in isolated epidermal cells

At a concentration of 1.25 mM, 14 amino acids were capable of inhibiting the induction of ornithine decarboxylase (L-ornithine carboxy-lyase, EC 4.1.1.17) activity by the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) in isolated epidermal cells. The greatest percentages of inhibition of TPA-induced epidermal ornithine decarboxylase activity were as follows: cysteine, 98%; tryptophan, 74%; methionine, 64%; phenylalanine, 51%; glycine, 44%; asparagine, 43%; glutamic acid, 42%; leucine, 40%; and arginine, 39%. These amino acid treatments did not alter the time- and concentration-response curves for induction of ornithine decarboxylase activity by TPA. Moreover, there was no difference between the rates at which [3H]arginine, [3H]leucine, [3H]phenylalanine, [3H]methionine, [3H]tryptophan and [14C]cysteine were taken up by freshly isolated epidermal cells or incorporated into epidermal proteins. Arginine, phenylalanine and methionine inhibited the induction of ornithine decarboxylase activity by the tumor promoter to degrees comparable to those elicited by their analogs canavanine and homoarginine, beta-2-thienyl-DL-alanine, and ethionine, respectively. These amino acids and amino acid analogs did not alter the overall rate of protein synthesis. In contrast, both the amino acids and their analogs increased the rates of proteolysis in isolated epidermal cells, an effect which correlated well with the abilities of these different compounds to inhibit TPA-induced ornithine decarboxylase activity. Moreover, both methionine and phenylalanine decreased the half-life and increased the rate of heat denaturation of the TPA-induced enzyme, a result identical to that obtained after treatment with the analogs ethionine and beta-2-thienyl-DL-alanine, respectively. Taken together, these results suggest that millimolar concentrations of exogenous amino acids might induce the synthesis of abnormal proteins and nonfunctional enzymes. Therefore, it is speculated that the uptake of unbalanced amounts of amino acids into the epidermal target cells might alter the stability and the ultrastructure of the TPA-stimulated enzyme just as the amino acid analogs do.
Endothelial cell protein C receptor plays an important role in protein C activation in vivo

Endothelial cell protein C receptor (EPCR) augments protein C activation by the thrombin-thrombomodulin complex about 5-fold in vitro. Augmentation is EPCR concentration dependent even when the EPCR concentration is in excess of the thrombomodulin. EPCR is expressed preferentially on large blood vessel endothelium, raising questions about the importance of protein C-EPCR interaction for augmenting systemic protein C activation. In these studies, this question was addressed directly by infusing thrombin into baboons in the presence or absence of a monoclonal antibody to EPCR that blocks protein C binding. Activated protein C levels were then measured directly by capturing the enzyme on a monoclonal antibody and assaying with chromogenic substrate. Blocking protein C-EPCR interaction resulted in about an 88% decrease in circulating activated protein C levels generated in response to thrombin infusion. Leukocyte changes, fibrinogen consumption, fibrin degradation products, and vital signs were similar between the animals infused with thrombin alone and those infused with thrombin and the anti-EPCR antibody. The results indicate that EPCR plays a major role in protein C activation and suggest that defects in the EPCR gene might contribute to increased risk of thrombosis.
Cocaine inhibits central noradrenergic and dopaminergic activity during the critical developmental period in which catecholamines influence cell development

Cocaine produces neurobehavioral damage in the fetus and neonate both through its ischemic actions and through direct effects mediated by the drug within the developing brain. The replication and differentiation of catecholaminergic target cells are controlled in part by neurotransmitter input and the current study assess whether cocaine modifies the function of these neurons during the critical periods in which target cell programming occurs. Neonatal rats (1, 7, 14 and 21 days old) were given cocaine (30 mg/kg) acutely and the turnover of norepinephrine and dopamine, a measure of synaptic activity, was evaluated in vivo in three different brain regions known to be adversely affected by cocaine. For norepinephrine, cocaine suppressed transmitter turnover in the immediate postnatal period in all regions, reaching a maximal effect within the first 2 postnatal weeks; at subsequent ages, the inhibitory actions were no longer evident. For dopamine, an inhibitory effect also appeared during the first postnatal week, but by 14 to 21 days the effect was replaced by the excitatory response that is characteristic of mature brain; effects on dopamine turnover were restricted to the forebrain. The inhibitory effects of cocaine on immature brain could not be attributed to localized actions at the nerve terminal itself (blockade of reuptake, autoreceptor activation, local anesthesia), but instead are likely to represent reductions in nerve impulse activity. Brain development in the neonatal rat corresponds to fetal stages in man, and thus the transient ability of cocaine to interfere with noradrenergic and dopaminergic activity during the period in which differentiation is being patterned by neurotransmitter input, may be important in the neurobehavioral teratology of cocaine.
Attenuated protein kinase C activity and translocation in Alzheimer's disease brain.

Abstract Protein kinase C (PKC) activity and its redistribution were determined in postmortem Alzheimer's disease (AD) and age-matched control brains. Cytosolic and membrane-associated PKC activities were lower in frontal and temporal cortices and hippocampi of AD brains. Increased concentrations of phosphatidyl- l -serine, Ca 2+ or phorbol 12-myristate, 13-acetate only weakly increased enzyme activity in AD tissues. Redistribution of cytosolic PKC to the membranous fraction was elicited in control brain slices by 162 nM PMA in the presence of K + (65 mM). This redistribution of the enzyme was markedly reduced in AD brain slices. In contrast, the immunoreactivity of the α- and γ-PKC isozymes were elevated in cortical tissue from AD subjects. No changes were noted in β-PKC immunoreactivity. These results suggest that the reduced PKC activity and the attenuated translocation of the enzyme in AD brain tissue may be attributed to down regulation of PKC or to alteration in PKC protein. The increase in PKC immunoreactivity may be a reflection of an altered susceptibility to proteolysis or a compensatory response secondary to the loss in enzyme activity.
High pressure synthesis of a new chromite, ScCrO3

A new compound, ScCrO{sub 3} has been synthesized at 45 kbar and 1,200 C using the cylindrical type press (USCA-1000). It has Pbnm symmetry with a = 5.0329(2) {angstrom}, b = 5.3602(3) {angstrom}, and c = 7.3790(4) {angstrom}, and its structure has been refined using the Rietveld technique and the synchrotron powder X-ray diffraction data.
Synthesis and characterization of electrospun nanocomposite TiO 2 nanofibers with Ag nanoparticles for photocatalysis applications

Polycrystalline mixed-phase TiO2 nanofibers embedded with 2.0% w/v Ag nanoparticles was prepared by the electrospinning technique. Calcination of dry Ag nanoparticles-titanium (IV) isopropoxide/PVP electrospun nanofiber mats in air at 510°C for 24 h yielded polycrystalline TiO2/Ag nanofibers. The morphology and distribution of silver nanoparticles were observed by transmission electron microscopy (TEM), scanning TEM (STEM), and high-angle annular dark-field (HAADF) imaging. Mixedphase anatase and rutile TiO2 nanofibers were produced with Ag nanoparticles. High-resolution TEM lattice-fringemeasurements showed good agreement with Ag (111), anatase (101), and rutile (110) phases. The photocatalytic activity of TiO2/Ag nanofibers was compared to the photocatalytic activity of pure TiO2 nanofibers by studying the photodegradation of methyl red dye under UV light irradiation, in a photoreactor. UV-visible absorbance spectra showed that the rate of decay of the dye in case of photodegradation by TiO2/Ag nanofibers was 10.3 times higher than that by pure TiO2 nanofibers. The retaining of the fiber morphology along with the increased surface area due to the addition of Ag nanoparticles can be believed to enhance the photocatalytic oxidation of methyl red dye.
Preparation of oxide superconductive composite by an electrostatic mixing process

Abstract This paper is concerned with the proposal of aerosol composite particles as raw powder for preparing superconductive composite. The composite particles were synthesized by using an electrostatic adhesion force acting between the electronegatively charged Ba2YCu3O7−x particle and the electropositively charged BaZrO3 particles. The amount of BaZrO3 coated on a Ba2YCu3O7−x particle was controlled by adjusting the ratio of the imparted charge. Superconductive composite bulk body was obtained, in which the fine BaZrO3 particles, less than 100 nm in diameter, were uniformly distributed. The improvement of Jc values of the composite sintered body was attributed to the contribution of charging to flux pinning enhancement caused by homogeneous distribution of pinning centers.
Activity-induced fiber regeneration in rat soleus muscle.

In an attempt to understand why muscle recovery is limited following atrophy due to limb immobilization, satellite cell activity and muscle fiber regeneration were analyzed in rat soleus muscles. Adult rat hindlimbs were immobilized in plaster casts for a period of two to ten weeks. Soleus muscles were examined by electron microscopy for evidence of fiber degeneration or regeneration, and to quantify satellite cell nuclei. Immunocytochemical localization of embryonic myosin was used to identify regenerating myofibers. Soleus muscle wet weight to body weight ratios for the casted muscles significantly decreased over the 10-week immobilization period. The casted muscles displayed ultrastructural evidence of minor fiber damage, including myofibrillar atrophy, Z-disc disruption, and abnormal triadic junctions. No ultrastructural evidence of regeneration was seen in the casted animals. The number of satellite cells in the casted muscles significantly decreased from 6.4% to 3. 3% by eight to 10 weeks of immobilization. Approximately 1.0% of extrafusal fibers in the control soleus muscles appeared to be regenerating since they expressed embryonic myosin and were of a small diameter, while in casted muscles, only 0.1% of the fibers were embryonic myosin-positive. Following release from immobilization, a reappearance of embryonic myosin-positive fibers was noted within four days of renewed activity. In contrast to control muscles, embryonic myosin-positive fibers in the recovery muscles included both small and large diameter fibers. Subtle changes in functional activity influence muscle damage and subsequent myofiber regeneration. Reduced activity reduces muscle fiber regeneration, while increased activity, as seen by increased hindlimb weight bearing and return to normal activity following immobilization, increase regenerating fibers and also the expression of embryonic myosin in adult fibers.
Calculation of the isotope cluster for polypeptides by probability grouping.

This paper presents a novel theoretical basis for accurately calculating the isotope cluster of polypeptides. In contrast to previous approaches to this problem, which consider exhaustive or near exhaustive combinations of isotopic species, the program, Neutron Cluster, groups probabilities to yield highly accurate information without elucidating any fine structure within a nominal mass unit. This is a fundamental difference from any previously described algorithm for calculating the isotope cluster. As a result of this difference, the accurate isotope clusters for high molecular weight polypeptides can be calculated rapidly without any pruning. When applied to isotope enriched polypeptides, the algorithm introduces “grouping error”, which is described, quantified, and avoided by using probability partitioning.
DEPTH-DEPENDENT LINE BLANKETING BY NEUTRAL AND IONIZED METALS IN A HOMOGENEOUS MODEL SOLAR PHOTOSPHERE.

Line blanketing due to both the neutral and ionized metals is treated here by the modified picket-fence method and applied to the case of a homogeneous model solar photosphere in strict radiative equilibrium. Improvement in fitting the observed photospheric radiation field is noted over a model in which the line absorption coefficient is constant with depth.
Filtration of lake natural organic matter: Adsorption capacity of a polypropylene microfilter

Abstract Although natural organic matter (NOM) is known to adsorb on filtration membranes, little is known about whether membranes possess an adsorption capacity for NOM. In this research, 4000 mL of particle-free lake water containing dissolved NOM was filtered through a 0.2-μm polypropylene (PP) microfiltration membrane. Permeate was collected over 10 batches of 400 mL each. A 100-mL sample from each batch of permeate was then filtered through a fresh 20,000 Da molecular weight cut-off (MWCO) polyethersulfone (PES) ultrafiltration membrane. It was observed that later batches of microfiltration permeate caused more ultrafiltration membrane fouling than earlier batches of permeate. This suggests an adsorption capacity for the PP microfilter, and this was determined to be about 14 mg of DOC adsorbed per gram of PP membrane. A mass balance across the microfilter revealed that about 85% of DOC in the lake water did not cause fouling. Used PES ultrafilters were analyzed using scanning electron microscopy, and while there was a slight increase in material deposited on the ultrafilter for later batches of microfiltration permeate, a clean membrane surface was apparent in all micrographs. This suggests that the NOM responsible for membrane fouling was smaller than the pores of the 20,000 Da PES ultrafiltration membrane. These findings provide useful insights into membrane fouling, and suggest that adsorptive fouling should be considered in the design of membrane processes used to filter natural waters.
Temperature-compensated fiber specklegram strain sensing with an adaptive joint transform correlator.

A temperature-compensated fiber specklegram strain sensor with an adaptive joint transform correlator (JTC) is presented. By exploiting the dual-channel correlation of the fiber specklegram JTC, we can measure the temperature-compensated strain. Experimental results have shown that the strain sensitivity can be as high as 0.1 μstrain/1 °C.
Photolysis of aldrin and dieldrin in a phytoplankton

Residues of aldrin and dieldrin in the green alga,Euglena gracilis (chloroflagellate), in the presence of fluorescent, blue or red light, are converted to photoaldrin and photo-dieldrin, respectively. This photoisomerization does not occur in the dark or in the presence of green light. Similar exposure ofTetrahymena orParamecium to room light does not show any photolysis indicating that the green pigment may be responsible for this photolysis. The extracted chlorophyll is capable of carrying out this photoisomerization, and this photolysis can be inhibited by the photosynthesis inhibitor, monuron. That this phytoplankton can perform photolysis of these aquatic pollutants indicates the potential of phytoplanktons in altering the chemical and biological characteristics of hazardous chemicals present in surface waters.
Antifungal susceptibility testing of micafungin against Candida glabrata isolates.

Objective Antifungal susceptibility of micafungin against isolates of C. glabrata was performed to evaluate the hypothesis that micafungin may be a suitable alternative in treating those patients whose infections are from C. glabrata and have developed resistance to fluconazole. Study design A total of 119 clinical isolates were obtained from the oral cavity of 22 patients with oropharyngeal candidiasis or oral colonization with C. glabrata. All strains evaluated were from patients who had either HIV infection or were receiving radiation therapy for head and neck cancer. Inocula were prepared using Clinical Laboratory and Standards Institute (CLSI) M27-A2 guidelines. The plates were incubated at 35°C and the minimum inhibitory concentrations (MICs) were determined at 24 and 48 hours. Results Micafungin exhibited good in vitro activity against most isolates, including those showing marked resistance to fluconazole. Conclusion Micafungin has excellent antifungal effects in vitro against C. glabrata isolates and appears to be a good treatment option even against those isolates resistant to fluconazole. A clinical trial should be performed to confirm these findings.
Human neuropsychology: Some differences between korsakoff and normal operant performance

Operant reinforcement schedules were used to investigate the effects of changes in reinforcement rates on the behavior of alcoholic Korsakoff (amnesic) patients and normal control subjects. In one test, both groups were exposed to pairs of variable-interval (VI) reinforcement schedules which operated concurrently. The distribution of reinforcements controlled the distribution of responses of normal subjects to a significantly greater extent than those of the Korsakoff patients. In a second test, two VI reinforcement schedules were arranged to run one at a time in succession. Reinforcement-rate differences with the successive (multiple) schedules did not produce corresponding response-rate differences for either group of subjects. The findings stress the complexity of the alcoholic Korsakoff syndrome, and emphasize the need to consider possible motivational abnormalities as determinants of alcohol-induced amnesia. In addition, results underscore both the value and the limitations of using operant procedures in human learning research.
Membrane scission by the ESCRT-III complex

The endosomal sorting complex required for transport (ESCRT) system is essential for multivesicular body biogenesis, in which cargo sorting is coupled to the invagination and scission of intralumenal vesicles. The ESCRTs are also needed for budding of enveloped viruses including human immunodeficiency virus 1, and for membrane abscission in cytokinesis. In Saccharomyces cerevisiae, ESCRT-III consists of Vps20, Snf7, Vps24 and Vps2 (also known as Did4), which assemble in that order and require the ATPase Vps4 for their disassembly. In this study, the ESCRT-III-dependent budding and scission of intralumenal vesicles into giant unilamellar vesicles was reconstituted and visualized by fluorescence microscopy. Here we show that three subunits of ESCRT-III, Vps20, Snf7 and Vps24, are sufficient to detach intralumenal vesicles. Vps2, the ESCRT-III subunit responsible for recruiting Vps4, and the ATPase activity of Vps4 were required for ESCRT-III recycling and supported additional rounds of budding. The minimum set of ESCRT-III and Vps4 proteins capable of multiple cycles of vesicle detachment corresponds to the ancient set of ESCRT proteins conserved from archaea to animals.
A real-time multichannel DSP-based neural signal analysis system

A prototype system for real-time analysis of multineuron waveforms has been developed. The system incorporates a third-generation digital signal processor for performing simultaneous real-time detection and classification of neural firing activity on several input channels. The model system contains four input channels, but a study has shown that such a system may be capable to up to eight input channels per DSP. The processor has been programmed to perform the peak windowing, template matching, and principal components classification algorithms. The authors discuss the system that has been developed and present several performance figures for it. >
Existence of nonclassical solutions in a Pedestrian flow model

Abstract The main result of this note is the existence of nonclassical solutions to the Cauchy problem for a conservation law modeling pedestrian flow. From the physical point of view, the main assumption of this model was recently experimentally confirmed in [D. Helbing, A. Johansson, H.Z. Al-Abideen, Dynamics of crowd disasters: An empirical study, Phys. Rev. E 75 (4) (2007) 046109]. Furthermore, the present model describes the fall in a door through-flow due to the rise of panic, as well as the Braess’ paradox. From the analytical point of view, this model is an example of a conservation law in which nonclassical solutions have a physical motivation and a global existence result for the Cauchy problem, with large data, is available.
Perturbing Nuclear Transport in Drosophila Eye Imaginal Discs Causes Specific Cell Adhesion and Axon Guidance Defects

To study nucleocytoplasmic transport during multicellular development, we developed a sensitive nuclear protein import assay in living blastoderm embryos. We show that dominant negative truncations of the human nuclear transport receptor karyopherinbeta/Importinbeta (DNImpbeta) disrupt mRNA export and protein import in Drosophila. To test the sensitivity of different developmental processes to nuclear trafficking perturbations, we expressed DNImpbeta behind the morphogenetic furrow of the eye disc, at a time when photoreceptors are patterned and project their axons to the brain. DNImpbeta expression does not disrupt the correct specification of different photoreceptors, but causes a defect in cell adhesion that leads to some photoreceptors descending below the layer of ommatidia. The photoreceptors initially project their axons correctly to the posterior, but later their axons are unable to enter the optic stalk en route to the brain and continue to project an extensive network of misguided axons. The axon guidance and cell adhesion defects are both due to a disruption in the function of Ketel, the Drosophila ortholog of Importinbeta. We conclude that cell adhesion and axon guidance in the eye have specific requirements for nucleocytoplasmic transport, despite involving processes that occur primarily at the cell surface.
Acute lung injury and the coagulation pathway: potential role of gene polymorphisms in the protein C and fibrinolytic pathways

There is evidence that dysregulation of coagulation and fibrinolysis may participate in the pathogenesis of acute lung injury (ALI) and the acute respiratory distress syndrome (ARDS). Altered concentrations of several proteins of the coagulation and fibrinolytic pathways in plasma and pulmonary edema fluid from patients with acute lung injury have been related to the severity of lung injury and clinical outcomes. Polymorphisms in the genes encoding for proteins of the protein C and fibrinolysis pathways are known to regulate the production of the respective proteins. It is plausible that these polymorphisms may be associated with the susceptibility to and severity of illness in ALI and ARDS. Well-designed studies that examine the association of these polymorphisms with susceptibility and severity of ALI and ARDS are needed to test the influence of both genetic and environmental factors on the clinical outcomes in patients with ALI and ARDS. There are several important considerations in the design of these genetic association studies, including selection of candidate genes with the most biological plausibility, definition of the phenotype, selection of appropriate controls, determination of the appropriate sample size and assessment of Hardy-Weinberg equilibrium among controls as a measure of internal validity.
ALIGNED SINGLE-WALL CARBON NANOTUBES IN COMPOSITES BY MELT PROCESSING METHODS

Abstract This Letter describes the production of single-wall carbon nanotube (SWNT) – polymer composites with enhanced mechanical and electrical properties and exceptional nanotube alignment. A combination of solvent casting and melt mixing was used to disperse SWNT materials in poly(methyl methacrylate) (PMMA). Composite films showed higher conductivity along the flow direction than perpendicular to it. Composite fibers were melt spun to achieve draw ratios between 20 and 3600. The elastic modulus and yield strength of SWNT–PMMA composite fibers increased with nanotube loading and draw ratio. Polarized resonant Raman spectroscopy indicates that the nanotubes in the fibers are well aligned, with mosaic distribution FWHMs as small as 4°.
Photodesorption Dynamics in Threshold-Fluence UV Laser Induced Surface-Decomposition of Bi2Sr2CaCu2O8

In this article, we review experimental measurements taken in our laboratory for the low-fluence UV pulsed laser photodecomposition of the perovskite ceramic Bi2Sr2Ca Cu2O8. We present the measured photoejected product kinetic energy (KE) distributions, including that for the ion and the neutral, the atomic and polyatomic species. For the specific case of the neutral species desorption, we present new experimental results that elucidate the change in the photophysical desorption process as a function of the incident laser fluence. The results show the transition from the electronic-induced desorption to thermal evaporation as the laser fluence is increased. The KE distribution data suggests that for low-fluence laser excitation, the primary photodesorption process is two-hole localization at a binding site followed by coulomb repulsion. A fraction of the escaping ions acquire the full coulomb KE (e2/ro; ro internuclear distance). The neutral species acquire a partial fraction of the available KE (i.e., the KE gained prior to the neutralization). The appearance of polyatomic species desorption is explained via the spectator-stripping model.
Mobility and fractionation of rare earth elements in argillaceous sediments: Implications for dating diagenesis and low-grade metamorphism

Abstract We report Sm-Nd and Rb-Sr data for the fine fractions of Lower Paleozoic argillaceous rocks from Wales, UK and New York, USA, spanning the range of low-grade metamorphic conditions from the diagenetic zone (zeolite facies) to the epizone (greenschist facies). In all cases, leaching of the fine fractions results in a high 147 Sm 144 Nd (0.09–0.29) acid-soluble component and a complementary low 147 Sm 144 Nd (0.05–0.14) residual component. The observed fractionation is an ancient feature related to diagenesis, burial and metamorphism. The magnitude of Sm-Nd fractionation between leachates and residues, as well as the resulting Sm-Nd ages, vary as a function of grain size and metamorphic grade. Uncleaved Welsh mudrocks of the diagenetic zone yield Sm-Nd leachate-residue ages of 453–484 Ma, in agreement with their Llanviian to Caradocian biostratigraphic ages, whereas higher grade rocks of the anchizone and epizone yield Sm-Nd ages as young as 413 Ma. These ages are transitional between the time of deposition and the time of regional deformation related to the Acadian Orogeny at 390 Ma. Distinct convex-upward rare earth element (REE) patterns of the leachates suggest that the precipitation of early diagenetic apatite controls the trace element budget of the rock, forcing a depletion of middle REEs on the subsequently formed diagenetic phyllosilicates. The amount of organic matter present and the extent of later prograde reactions are probable modifiers of this fractionation process. Ordovician and Devonian clastic rocks associated with the Trenton and Onondaga limestones of New York yield single-sample and multi-sample Sm-Nd isochron ages that agree well with their biostratigraphic ages of 454 Ma and 390 Ma, respectively. The REE fractionation observed in shale leachates of the Ordovician Utica Formation is related to Ca/Mg of the bulk rock and hence to the composition of the diagenetic carbonate cement. In all cases the Sm-Nd system remained closed subsequent to the peak of diagenesis or metamorphism, including the North American rocks that show no evidence of being isotopically reset during widespread remagnetization of the subjacent limestone units in the late Paleozoic.
Survival and Staging Characteristics for Non–Squamous Cell Malignancies of the Maxillary Sinus

Objective To characterize the clinical behavior of non–squamous cell cancer of the maxillary sinus. Methods Cases of non–squamous cell maxillary sinus malignancy during 1988 through 1998 were extracted from the Surveillance, Epidemiology, and End Results database. Data for histologic type of tumor, tumor stage, and survival were analyzed using the Kaplan-Meier method to determine mean, median, and 5-year survival statistics for the overall cohort and for individual histologic types of tumor. The effect of tumor stage on overall survival was assessed. To determine relative survival, the non–squamous cell group was compared with a second group of patients with squamous cell carcinoma, matched according to age at diagnosis, year of diagnosis, and T stage. Results One hundred eighty-eight cases of non–squamous cell malignancy were identified. The mean patient age was 57.8 years, and 143 patients (76%) presented with T3 or T4 tumors. There were 31 adenocarcinomas, 64 adenoid cystic carcinomas, 15 mucoepidermoid carcinomas, 22 melanomas, 45 sarcomas, and 11 undifferentiated carcinomas. The overall mean survival was 63.4 months, and 5-year survival was 45.6%. Adenoid cystic carcinoma exhibited the best mean survival (79 months), whereas melanoma and undifferentiated carcinoma exhibited poor mean survivals (30.3 and 12.8 months, respectively). T stage did not statistically affect overall survival ( P = .86). Survival for patients with non–squamous cell cancer was substantially better than survival for the matched group with squamous cell carcinomas (mean survival, 41.5 months; 5-year survival, 27.4%). Conclusions Patients with non–squamous cell carcinoma of the maxillary sinus typically present with advanced T stage but have significantly better survival than patients with similar-stage squamous cell carcinoma of the maxillary sinus. T stage has less effect than histologic type of tumor on prognosis in non–squamous cell carcinoma of the maxillary sinus.
Assessment of the pain experience in relation to selected nurse characteristics

This study was designed to investigate the impact of select nurse characteristics (years in practice, age, relative job satisfaction, educational preparation, clinical practice area, cultural background and shift assignment) on assessments of patient pain and psychological distress. Fifty registered nurses were randomly selected from two surgical units, two medical units, and a combined intensive care unit/coronary care unit. Upon agreement to participate, an appointment was scheduled to administer the Standard Measure of Interferences of Suffering, the Job Descriptive Index, and a sociodemographic questionnaire. The results indicated that nurses inferred significantly less pain than psychological distress (t (98) = −12.68, P < 0.01). The relationships between nurses' assessments of pain and psychological distress and years in practice, age, and relative job satisfaction were weak and non-significant. The associations between educational preparation, clinical practice area, and shift assignment were also non-significant. Further analysis of the Standard Measure of Inferences of Suffering, in regard to the patient characteristics of age, sex, and illness/injury, demonstrated that only the category of illness/injury significantly influenced nurses' inferences of suffering ( F (4, 245) = 8.486, P < 0.01). In evaluating the differences for all categories of sex, age (4–12, 30–45, and 64 years and older), and illness/injury (cardiovascular, cancer, infection, trauma, and psychiatric), the ratings for psychological distress were again significantly higher than those for pain.
Preparation of Mesoporous Yttria-Stabilized Zirconia (YSZ) and YSZ-NiO Using a Triblock Copolymer as Surfactant

Mesoporous yttria-stabilized zirconia (YSZ) and YSZ–NiO have been prepared for the first time using Pluronic P103 as a structure-directing agent and inorganic chlorides as precursors in a nonaqueous medium. After being fired at 500°C for 2 h, mesostructured YSZ has a BET surface area of about 146 m2 g−1, with an average pore size of 3.8 nm, while mesostructured YSZ–NiO has a BET surface area of about 108 m2 g−1, with an average pore size of 4.5 nm.
"Crown Heights is the Center of the World": Reterritorializing a Jewish Diaspora

A story is sometimes told about a disciple of the Baal Shem ??? (the eighteenth-century founder of Hasidic Judaism) who yearned to see the Holy Land—or at least the story was told to me, one night ...
Love Gone Wrong, Then Right Again: Male/Female Dynamics in the Bahrām Gūr–Slave Girl Story

This article examines male/female dynamics in three versions of the classical story of the Sassanian prince Bahram Gur and his lyre-playing slave girl: that of the Shahnama of Firdawsi, the Haft Paykar of Nizami Ganjavi, and the Hasht Bihisht of Amir Khusraw. It argues that each version provides progressively more positive depictions of intergender dynamics, ones that are contingent upon more egalitarian understandings of the male/female dichotomy. The later authors destabilize the categories of “male” and “female,” equalizing and even uniting the dichotomous pairs, so that men and women draw nearer to each other in qualities rather than remaining in their usual polarized positions. In the Hasht Bihisht, moreover, we witness a reversal of hierarchies in which traditionally feminine qualities receive preference over masculine virtues—an act that suggests fresh possibilities for harmonious interactions between the sexes.
Failure of reactivation of chick erythrocytes after fusion with temperature-sensitive mutants of mammalian cells arrested in G1

Two temperature-sensitive (ts) mutants of mammalian cell lines (AF8 and cs4D3) that arrest in G1 at the nonpermissive temperature were fused with chick erythrocytes and the induction of DNA synthesis was studied in the resulting heterokaryons. While both AF8 and cs4D3 could induce DNA synthesis in chick nuclei at the permissive temperature, they both failed to do so when arrested in G1 at the nonpermissive temperature. When S phase AF8 cells were fused with chick erythrocytes, chick nuclei were reactivated even if the heterokaryons were incubated at the temperature nonpermissive for AF8. A third ts mutant, ts111, that is blocked in cytokinesis but continues to synthesize DNA, reactivated chick nuclei at both permissive and nonpermissive temperature. It is concluded that chick erythrocyte reactivation depends on the presence of S phase-specific factors.
Evidence of a Low-Barrier Hydrogen Bond in the Tryptophan Synthase Catalytic Mechanism†

In the absence of other substrates, l-Ser reacts rapidly with the tryptophan synthase α2β2 bienzyme from Salmonella typhimurium at pH 7.8 and 25 °C to give an equilibrating mixture of species dominated by comparable amounts of the l-Ser external aldimine Schiff base, E(Aex1), and the α-aminoacrylate Schiff base, E(A-A). The d-isomer of Ser is unreactive toward α2β2, and therefore, d,l-Ser can be used in place of l-Ser for investigations of catalytic mechanism. Due to the equilibrium isotope effect, when α-2H-d,l-Ser is substituted for α-1H-d,l-Ser, the position of equilibrium is shifted in favor of E(Aex1). On a much slower time scale, the 2H sample undergoes the exchange of enzyme bound 2H for the 1H of solvent water and is converted to a distribution of E(Aex1) and E(A-A) identical to that obtained with the 1H sample. This slow exchange indicates that the proton abstracted from the α-carbon of E(Aex1) is sequestered within a solvent-excluded site in E(A-A). Analysis of the UV/vis spectra gave an isotope...
Scale-Selective Bias Correction in a Downscaling of Global Analysis Using a Regional Model

Systematic large-scale errors are often found within the regional domain in the regional dynamical downscaling procedure. This paper proposes a method to suppress such errors using a combination of spectral tendency damping and area average correction of temperature, humidity, and surface pressure in the Regional Spectral Model. The proposed scale-selective bias-correction method reduces the time tendency of the zonal and meridional wind components for the physical scale greater than a predetermined length. In addition, the area mean perturbations of temperature and humidity are forced to zero. The surface pressure difference between the model field and the global field is adjusted from the hydrostatic equation using the mean elevation difference between the two fields and the area mean temperature. Each of these three components of the technique is necessary for the model to effectively reduce large-scale errors in the regional domain. With this method, the downscaled field becomes less dependent on the domain size. Furthermore, the downscaled precipitation compares better with observations, as do the near-surface temperature and wind fields. The scheme allows much weaker lateral boundary relaxation, although it is still an essential part of the regional model. The use of a similar scheme is recommended for any regional model in the application of dynamical downscaling of analysis for climate studies.
Two new notoungulates (Family Notohippidae) from the Salla Beds of Bolivia (Deseadan: late Oligocene): systematics and functional morphology

ABSTRACT Three notohippids from the Salla Beds of Bolivia (Deseadan, late Oligocene) are described: Pascualihippus boliviensis, gen. et sp. nov., Eurygenium pacegnum, sp. nov., and Rhynchippus sp., cf. R. brasiliensis. P. boliviensis has a transverse premaxillary dental arcade similar to that of toxodontids, suggesting a close relationship to the origins of Toxodontidae. E. pacegnum is represented by a virtually complete articulated skeleton, having a tetradactyl manus and proximal third trochanter, whereas Rhynchippus equinus and early toxodontids share the derived conditions of tridactyl manus and more distally placed third trochanter. Phylogenetic analysis suggests that toxodontids are nested within the paraphyletic Notohippidae. A recent, more inclusive concept of notohippids may also include Leontiniidae. The relative height of tooth crowns and relative width of muzzles were used to infer the feeding ecologies of Salla notohippids. Based on its broad muzzle, Pascualihippus is hypothesized as being pr...
Foundation of Linear Programming: A Managerial Perspective from Solving System of Inequalities to Software Implementation

The aim and scope of this paper are the infusion of purposeful action by decision makers with an explicit understanding of analytical linear programming (LP) tools in order that the managers will implement strategic results correctly. The advances in computing software have brought LP tools to the desktop for a variety of applications to support managerial decision-making. However, it is already recognized that current LP tools do not answer the managerial questions satisfactorily. For instance, there is a costly difference between the mathematical and managerial interpretations of sensitivity analysis. The LP software packages provide sensitivity results about the optimality of a basis and not about the optimality of the values of the decision variables, and the shadow prices that are of interest to the manager. Society has developed the largest sensitivity region based on â€œoptimal solution,â€ not that which â€œpreserves the basisâ€ that allows for simultaneous dependent/independent changes. The aim and results of this article are found further in the work.
Functional Anatomy of Incisal Biting in Aplodontia rufa and Sciuromorph Rodents – Part 1: Masticatory Muscles, Skull Shape and Digging

Traditionally, rodents have been grouped into suborders distinguished largely on the basis of characteristics of the jaw adductor muscles and other features of the masticatory apparatus. The three classic suborders are: Sciuromorpha (squirrels), Myomorpha (rats and mice), and Hystricomorpha (porcupines and the South American caviomorph rodents). Protrogomorph rodents are thought to represent the primitive condition of rodent masticatory muscles. Aplodontia rufa, the mountain beaver, is the only living protrogomorphous rodent. The present work is a detailed comparison of the masticatory apparatus in A. rufa and Marmota monax, the woodchuck. But the mandibular region of A. rufa appears remarkable, unlike anything found in other rodents. Is A. rufa a reasonable representative of the primitive, protrogomorphous condition? A.rufa is a member of the aplodontoid-sciuroid clade with a wide and flat skull. The large temporalis and mandibular apophyses of A. rufa are features related to its relatively wide skull. Such features are found in less dramatic forms in other sciuromorphous species and the basic arrangement of the masticatory muscles of A. rufa is similar to the arrangement seen in sciuromorphs.
Effects of diamide on basal and thyrotropin-stimulated thyroid metabolism.

The effect of diamide on basal and TSH-stimulated thyroid metabolism was studied using bovine and dog thyroid slices. Diamide (10 DIM) inhibited basal and TSH-stimulated net cAMP production, basal and cAMP-stimulated protein kinase activity, and stimulation by TSH of colloid droplet formation and organisation of iodide and abolished basal and TSH-stimulated uptake of 32P into phospholipids. In thyroid slices incubated with 0.1 mM diamide, none of these activities, whether basal or TSH-stimulated, was affected. However, 0.1 mM diamide increased the net basal production of cAMP and potentiated the effect of TSH on this process. These results demonstrate that the previously reported inhibition of protein kinase by 2–20 mM diamide is not specific and that this compound cannot be used to determine which of the metabolic effects of TSH are dependent upon cAMP activation of protein kinase. While 0.1 mM diamide increased cAMP in thyroid slices, it did not reproduce any of the other effects of TSH.
Inflation and economic development in Latin America: Some new evidence

This article presents an evaluation of various relationships that explain shifts in economic structure. These are (1) inflation as measured by (a) the wholesale price index, and (b) sectoral price index; (2) changes in sectoral profits; and, (3) changes in alternate sectoral profits. Changes in sectoral profits (measured by sectoral price minus wholesale price) were more strongly correlated to changes in economic structure than either wholesale or sectoral price indices, while changes in economic structure are as expected when compared to changes in alternate sectoral profits in all but three of the years studied.
Airborne lidar observations of ozone and aerosols in the wintertime Arctic stratosphere

The procedures used in making the lidar measurements of O3 and aerosols are discussed, and selected data samples of O3 and aerosol distributions observed during flights between Stavanger (59 deg N, 3 deg E) and the North Pole between about 40 deg W and 20 deg E meridians are presented. The 'on' and 'off'; laser wavelengths used for the DIAL measurements during the Airborne Arctic Stratospheric Expedition (AASE) were 301.5 and 311 nm, respectively. An intercomparison between airborne DIAL and ozonesonde measurements of O3 in the vicinity of Bear Island is shown. The DIAL profiles were obtained by averaging the lidar returns over a 5-min period and then calculating the DIAL O3 profile. Lidar measurements at 603 and 1064 nm are used to infer physical characteristics of the different types of aerosols observed during the AASE.
Modesty in the Service of Justice: Retrieving Tradition and Reversing the Gaze

In recent years, concern for “modesty” has become more prominent in American religious circles. Recent advocates of modest clothing for women voice important concerns, but also perpetuate problematic attitudes toward women, especially poor women and women of color. Thomas Aquinas' description of modesty corrects this error, because it includes modesty of the mind. Contemporary developments in moral theology then enable us to relate both mental and physical modesty to the cardinal virtue of justice, where modesty decenters the self and makes room for other people to flourish. Findings from social psychologists illuminate the dynamics of social power, and clarify specific ways that mental and physical modesty work under the rubric of justice. These findings suggest that men and women may face different challenges in the practice of modesty, and so Christians must attend to all types of modesty in order to adequately address the question of appropriate clothing.