cssi/SciSciGPT-SciSciNet huggingface dataset:
Contributions of habitat sampling and alkalinity to diatom diversity and distributional patterns in streams: implications for conservation

Diatoms, microscopic unicellular algae, have been widely sampled from streams around the world because of their use in biological assessments, but as a result they are often only collected from epilithic habitats in riffles, which may lead to a substantial underreporting of their diversity and distributional patterns. The goals of this study were to identify how sampling methods and water chemistry affect the characterization of local and regional diversity and distributions. Species richness, Shannon diversity, and evenness were significantly greater in multiple habitat (MH) than epilithic habitat (EH) samples (paired t-test; P 75, >50, and >25% of sites, respectively, whereas 1, 14, and 34 were collected from EH samples, respectively. Regional abundance more strongly predicted site frequency than mean local abundance. Smaller drainage basins tended to have fewer species, likely because of species-area relationships, but local factors (% EH and alkalinity) influenced the taxonomic complexity of assemblages. Diversity was greatest at intermediate % EH, but low alkalinity reduced diversity, which is potentially important for ecosystems affected by anthropogenic acidification, as in our study. Multiple habitats need to be sampled for better documenting diatom diversity and distributions, which could improve conservation efforts at local and regional scales along with the characterization of ecological patterns and processes.
Three-Selmer groups for elliptic curves with 3-torsion

We consider a specific family of elliptic curves with rational 3-torsion subgroup. We arithmetically define 3-Selmer groups through isogeny and 3-descent maps, then associate the image of the 3-descent maps to solutions of homogeneous cubic polynomials affiliated with the elliptic curve E and an isogenous curve E′. Thanks to the work of Cohen and Pazuki, we have solubility conditions for the homogeneous polynomials. Using these conditions, we give a graphical approach to computing the size of 3-Selmer groups. Finally, we translate the conditions on graphs into a question concerning ranks of matrices and give an upper bound for the rank of the elliptic curve E by calculating the size of the Selmer groups.
The Development of Photosynthesis in a Greening Mutant of Chlorella and an Analysis of the Light Saturation Curve

Photosynthetic oxygen evolution considerably precedes the rise in chlorophyll during the greening of a yellow mutant of Chlorella vulgaris. Dark-grown cells required 20 times more light to saturate photosynthesis than light-grown or normal cells. The chlorophyll appears to add first to active reaction centers, then to fill in a more general antenna. The carotenoid pigments seem to add more randomly to the reaction centers. The shape of the light saturation curves can be explained with the assumption that an excitation in the antenna can reach several reaction centers. The efficiency of the total unit is constant during the greening process.
Hydrogen-generating solid-state hydride/hydroxide reactions

Abstract Solid-state reactions of ionic hydrides with alkaline hydroxides are shown to produce hydrogen gas and metal oxides. These reactions are analogous to the well-known hydrolysis reactions of ionic hydrides. Both classes of reactions are generally exothermic and are thermodynamically favored; Δ G ° 2 evolution beginning at ∼50 °C and complete reaction occurring by 200–300 °C. The reaction rate can be enhanced with additives such as TiCl 3 . Specifically, we discuss the reactions LiH + LiOH, 2LiH + NaOH, LiBH 4 + 4LiOH, and 3LiBH 4 + 4LiOH·H 2 O. The 3LiBH 4 + 4LiOH·H 2 O reaction generates approximately 10 wt.% hydrogen with more than 5 wt.% produced at temperatures below 100 °C.
Recent Advances in Electric Arc Plasma Generation Technology

A state-of-the-art review is presented vith particular attention to arc- heated wind tunnels and space engines. The material is divided into sections on applications, design and operating characteristics, and factors affecting performance. The applications discussed are chemical synthesis, refractory processing, high-temperature research, reentry simulation, and space propulsion. The recent types of plasma generators nearly all have rotational symmetry with coaxial electrodes with an annular gap for the arc and through which the gas flows. The three principal configurations in use are cylindrical, toroidal, and constricted. The voltage-current characteristics, calibration procedures, operating limits, contamination, a-c operation, and r-f heating are also discussed. The factors affecting plasma generator performance are discussed as convective and radiative heat losses, electrode processes, arc-column behavior, and magnetic -field effects.
Time for a change

Prokaryote: gene-sequence comparisons show the tree of life consists of bacteria, eukarya and archaea. The use of the term 'prokaryote' fails to recognize that an idea about life's origins has been proved wrong.
Intercomparison of photoacoustic and thermal-optical methods for the measurement of atmospheric elemental carbon

Two atmospheric elemental carbon measurement methods based on different analytical principles have been compared using data collected during the summer of 1987 at the Claremont, California site of the Southern California Air Quality Study (SCAQS). An optical absorption method, photoacoustic spectroscopy, measured the visible light absorption (γ = 514.5 nm) of atmospheric elemental carbon in its natural aerosol-state in real time. Elemental carbon concentrations were obtained by applying the appropriate value of the absorption cross-section for elemental carbon to the optical absorption data. The other method was a thermal-optical technique, which measures elemental and organic carbon concentrations on a filte--collected sample by combustion and corrects for the pyrolytic conversion of organic to elemental carbon by measuring the transmittance of laser light through the sample. Aerosol was collected on a filter mounted inside the carbon analyzer and analyzed in place. A 2-h collection and analysis cycle was used. The real-time photoacoustic data integrated over ∼100 min were compared with thermal-optical data. The two methods compare quite well. The linear least squares fit gave a correlation coefficient of R=0.905, and no significant difference was seen between the two data sets at the 95% confidence level.
Microinjection of calpastatin inhibits fusion in myoblasts.

Abstract Rat satellite cells (RSC) were microinjected with purified calpastatin or m-calpain, and myoblasts from a C 2 C 12 mouse line were microinjected with purified calpastatin. Microinjection with calpastatin completely prevented fusion of myoblasts from both sources, whereas microinjection with m-calpain significantly increased the rate of fusion of cultured RSC; 44% of the nuclei of RSC cultures were in multinucleated myotubes within 48 h after microinjection with m-calpain plus labeled dextran, whereas only 15% of the nuclei were in multinucleated myotubes after microinjection with dextran alone. Western analyses indicated that neither RSC nor C 2 C 12 myoblasts contained detectable amounts of μ-calpain before fusion. The levels of calpastatin in C 2 C 12 myoblasts increased as cells passed from the proliferative stage to the onset of fusion, and these levels increased substantially in both the C 2 C 12 and the RSC cells as they progressed to the late or postfusion stage. Both RSC and C 2 C 12 myoblasts contained an 80-kDa polypeptide that was labeled with an anti-m-calpain antibody in Western blots. The results are consistent with a role of the calpain system (m-calpain in these myoblast lines) in remodeling of the cytoskeletal/plasma membrane interactions during cell fusion.
Synthesis and Properties of Chiral Self-Assembling Lamellar Polydiacetylene Systems with Very-Long-Range Order

Two new, very accessible, chiral, self-assembling phospholipid analogues containing diacetylenic units in the middle of their acyl chains were prepared by very simple and highly efficient routes. Films were cast and then polymerized by activation with UV light or doped with iodine. X-ray diffraction, NMR spectroscopy measurements, and molecular mechanics analyses using the MM3 force field indicated that the acyl chains are closely packed in a parallel fashion. The new molecules and the polymerized films derived from them were characterized by a variety of physical methods including confocal polarized light microscopy, atomic force microscopy, and near-infrared spectroscopy. These analytical methods showed that the unpolymerized molecules are able to form lamellar systems with very-long range order. They formed very uniform, extremely flat, thin films which are readily polymerized to give extensively conjugated systems which absorbed well out into the near-infrared region unlike typical polydiacetylenes. T...
Fractures in Biliary Atresia Misinterpreted as Child Abuse

Bone fractures in children without a history of injury are highly suspicious for child abuse. Biliary atresia is a disorder associated with metabolic bone disease, and there are numerous reports of osteopenia, rickets, and/or fractures in this population. We report 3 cases of children with biliary atresia who had bony fractures as well as osteopenia whose caretakers were investigated for child abuse. Pediatricians should be aware of an increased incidence of fractures and overall prevalence of bone disease in this population.
Abyssal Dunes of Foraminiferal Sand on the Carnegie Ridge

A field of sand dunes was discovered by the side-looking sonars of a deep-towed geophysical instrument package at a water depth of 2.65 km on the north flank of the Carnegie Ridge in the eastern equatorial Pacific. The dunes are moving down the flat floor of an erosional valley that has been excavated through calcareous ooze to a resistant, manganese-encrusted chalk stratum. Transverse dunes (mean wave length 20 m) anc barchans (length 6 to 80 m) are arranged in long, narrow belts. Stereo photographs (875 oriented pairs) of the dunes and of the current-swept rock floor show that average dune height is —0.6 m, the steep (25° to 30°), lee side is generally smooth, and the upstream slope is covered with short-crested current ripples. A core from a transverse dune recovered moderately sorted sand, composed of broken fragments (70 percent) and intact tests of Quaternary age Foraminifera. Photographs and side-looking sonar records both indicate a northwestward, down-valley sediment transport. The dunes are thought to be formed and propelled by fast (>30 cm/sec) currents of dense water, which spill episodically over the Carnegie Ridge into the Panama Basin.
Exposure to fall hazards and safety climate in the aircraft maintenance industry.

Abstract Problem Falls represent a significant occupational hazard, particularly in industries with dynamic work environments. This paper describes rates of noncompliance with fall hazard prevention requirements, perceived safety climate and worker knowledge and beliefs, and the association between fall exposure and safety climate measures in commercial aircraft maintenance activities. Methods Walkthrough observations were conducted on aircraft mechanics at two participating facilities (Sites A and B) to ascertain the degree of noncompliance. Mechanics at each site completed questionnaires concerning fall hazard knowledge, personal safety beliefs, and safety climate. Questionnaire results were summarized into safety climate and belief scores by workgroup and site. Noncompliance rates observed during walkthroughs were compared to the climate-belief scores, and were expected to be inversely associated. Results Important differences were seen in fall safety performance between the sites. The study provided a characterization of aircraft maintenance fall hazards, and also demonstrated the effectiveness of an objective hazard assessment methodology. Noncompliance varied by height, equipment used, location of work on the aircraft, shift, and by safety system. Discussion Although the expected relationship between safety climate and noncompliance was seen for site-average climate scores, workgroups with higher safety climate scores had greater observed noncompliance within Site A. Overall, use of engineered safety systems had a significant impact on working safely, while safety beliefs and climate also contributed, though inconsistently. Impact on Industry The results of this study indicate that safety systems are very important in reducing noncompliance with fall protection requirements in aircraft maintenance facilities. Site-level fall safety compliance was found to be related to safety climate, although an unexpected relationship between compliance and safety climate was seen at the workgroup level within site. Finally, observed fall safety compliance was found to differ from self-reported compliance.
Salinity tolerance and the responses to hypoosmotic stress of the bay squid Lolliguncula brevis, a euryhaline cephalopod mollusc

Abstract 1. 1. The blood osmotic concentrations of trawl-caught Lolliguncula brevis were measured in the field, at Galveston Bay, Texas; in each case, the osmolality was similar to that of the seawater in which the animal was captured. 2. 2. The squid could also be maintained in large tanks with a closed circulating seawater system; therefore, the effect of hypoosmotic stress on blood osmotic concentration could be studied under controlled conditions. 3. 3. The lowest salinity compatible with survival and normal behavior is about 17.5‰ Squids showed signs of severe osmotic stress in salinities below 17‰ and died after 48 hr in 16.5‰ 4. 4. Throughout the salinity range tested (17.5–36‰), blood osmotic concentration conformed to that of the ambient seawater, remaining slightly hyperosmotic to the external medium. 5. 5. Thirty minutes after a reduction in salinity from 36–28‰, the blood was half equilibrated with the ambient seawater; complete equilibration occurred in about 4hr. Muscle water of hydration increased by 4% within 1 hr. 6. 6. Lolliguncula brevis is unique: a euryhaline, osmoconforming cephalopod.
A new direction in personal computer software

The "personalization" of computers is made possible by three major factors--advances in microelectronics, the availability of inexpensive software for a spectrum of applications, and the increased user-friendliness of computer systems. This paper examines the trends in software development, and presents estimates of the escalating costs involved in such development. Major studies by AT & T and by others stress that the true need is for more sophisticated and effective communication tools rather than for more computing power. Effective communication often pivots around the impact of diverse types of information--numeric, textual, and pictorial. Current endeavors are towards refining and integrating several existing technologies to implement software that enables programmers and non-programmers alike to readily manipulate images comprised of different types of information. This paper examines the emerging field of presentation graphics software and presents details of a new product in this nascent field. The conclusion emphasizes the impact of graphic computing in enlarging the spectrum of personal computer applications.
Modification of Dornier HM-4 Lithotriptor for Pediatrie Extracorporeal Shockwave Lithotripsy

Extracorporeal Shockwave lithotripsy has enjoyed increasing acceptance and utility in pediatrie urology. The Dornier HM-4 lithotriptor has had good results in adults, but the gantry design does not allow smaller children to be treated. We have employed a specially designed yet simple "spacer" to allow smaller children to be treated safely. The device may also have application in older patients with deformities who could not be treated in the past.
The structure, function, and regulation of cytochrome P450 2A enzymes

(1997). The Structure, Function, and Regulation of Cytochrome P450 2A Enzymes. Drug Metabolism Reviews: Vol. 29, No. 4, pp. 977-996.
Polarity proteins PAR6 and aPKC regulate cell death through GSK-3β in 3D epithelial morphogenesis

Epithelial cells are polarized, with an apical surface facing a lumen or outer surface and a basolateral surface facing other cells and extracellular matrix (ECM). Hallmarks of epithelial carcinogenesis include loss of polarity, as well as uncontrolled proliferation and resistance to apoptosis. Are these features controlled by a common molecular mechanism? The partitioning-defective 3 (PAR3)-PAR6-atypical PKC (aPKC) complex is a master regulator that controls polarization in many animal cells. Here we show that PAR6 is involved in apoptosis by regulating aPKC and glycogen synthase kinase 3beta (GSK-3beta) activity. During epithelial morphogenesis in 3D culture of Madin-Darby canine kidney (MDCK) cells, expression of an N-terminally deleted PAR6 (PAR6DeltaN) leads to a significant increase in caspase-dependent cell death by downregulating aPKC activity. Accordingly, inhibition of aPKC in wild-type (WT) MDCK cells with either a cell-permeable PKCzeta pseudosubstrate or RNAi promotes apoptosis, which suggests that PAR6 regulates apoptosis via an aPKC-mediated pathway. GSK-3beta, a substrate of aPKC, is hyper-activated by expressing PAR6DeltaN. GSK-3beta inhibitors block PAR6DeltaN-induced apoptosis while expression of constitutively active GSK-3beta (S9A) promotes apoptosis, which is rescued by ectopic expression of aPKC. We conclude that a PAR6-aPKC-GSK-3beta mechanism links cell polarity and apoptosis.
Ontogeny of the regulation of Na+,K(+)-ATPase activity in the renal proximal tubule cell.

ABSTRACT: This study examines the ontogeny of the regulation of Na+,K+-ATPase activity in the proximal tubule (PT) by a first messenger, dopamine (DA), and by direct stimulation of a third messenger, protein kinase C (PKC). PT segments dissected from 10− (PT10), 15-(PT15), 20− (PT20), and 40− (PT40) d-old rats were preincubated with DA 10−5 M, diacylglycerol (DAG) 10−5 M (an endogenous activator of PKC), or phorbol 12,13-dibutyrate (PDBu) 10−6 M (an exogenous activator of PKC). DA inhibited Na+,K+-ATPase activity in PT40. In PT20, DA also inhibited Na+,K+-ATPase activity, but the inhibitory effect in PT20 was less pronounced than in PT40. In PT15, DA had no effect on Na+,K+-ATPase activity. DAG significantly inhibited Na+,K+-ATPase activity in PT40. DAG also inhibited Na+,K+-ATPase activity in PT20, but the inhibition was slightly less pronounced than in PT40. DAG had no effect on Na+,K+-ATPase activity in PT15. Na+,K+-ATPase activity in PT40 and PT20 preincubated with PDBu was significantly lower than with vehicle. The inhibitory effect in PT20 was less pronounced than in PT40. When PT40 and PT20 were preincubated with both PDBu and 5 × 10−5 M sphingosine, an inhibitor of PKC activation, the inhibitory effect of PDBu was abolished. In both PT40 and PT20 incubated with 4-α-12,13 phorbol didecanoate 10−7 M, a phorbol ester that will not activate PKC, Na+,K+-ATPase activity was not different from the control. In PT10, Na+,K+-ATPase activity was the same after PDBu incubation and after vehicle incubation. Na+,K+-ATPase activity in PT10 incubated with both PDBu and sphingosine was not different from the control. PDBu inhibited Na+,K+-ATPase activity in a dose-dependent way in PT40 and PT20 but not in PT10. We conclude that the short-term regulation of renal tubular Na+,K+-ATPase activity undergoes postnatal changes.
One year of tracer dispersion measurements over Washington, D.C.

Abstract Two perfluorocarbon tracers were released for 6 h from several locations about 20 km outside of Washington, D.C. at 36-h intervals for over 1 year. Continuous air samples were collected at 8-h intervals at one urban and two suburban sites, and at monthly intervals at 93 sites all over the region. Over 50 % of the 8-h samples showed no tracer concentration. However, about 20% of the samples had significant amounts of tracer, so that about 600 values under a variety of meteorological conditions are available for analysis. Although the Potomac River is only 100 m below the surrounding terrain, the tracer releases from within the river valley indicated that the tracer flow was channeled along the river valley. For tracer released away from the river valley, the tracer tended to pass aloft and not mix down into the river valley. Sequential concentration measurements frequently showed high values for extended periods after the tracer release terminated, decreasing exponentially with a half life of about 3 h. This suggests that the finite tracer plume may have a rather long upwind trailing edge toward the release point. The average rate of change in the vertical dispersion during summer and winter was found to be proportional to the 0.6 power of distance.
ERIOPHYID MITES IN RELATION TO KENTUCKY BLUEGRASS SEED PRODUCTION

Two mite species, Abacarus hystrix (Nalepa) and Aculodes mckenziei (Kiefer) (Acarina: Eriophyidae) are reported from Kentucky bluegrass, Poa pratensis L., in Minnesota. Abundance of these mites was monitored in Kentucky bluegrass seed fields where postharvest residue was either clipped or burned. Adult and immature mites were significantly (P < 0.05) more numerous in biweekly samples taken from clipped plots in comparison to burned plots. Plant biomass and seed yield were significantly (P < 0.05) greater in burned plots. In a laboratory experiment, plant height and weight of Kentucky bluegrass were significantly (P < 0.05) lower in replicates artificially infested with mites when compared with uninfested replicates. The evidence suggested that these mite species reduced seed yield and inhibited plant growth. RESUME Acariens eriophyides et production de graines par Poa pratensis Deux especes d'acariens: Abacarus hystrix (Nalepa) et Aculodes mckenziei (Kiefer) ont ete signalees sur Poa pratensis L. au Minnesota (U.S.A.)- L'abondance de ces acariens a ete evaluee sur champs de semence de P. pratensis dont les residus avaient ete soit fauches, soit brules apres la recolte. Les acariens immatures et adultes etaient significativement plus nombreux (P < 0,05) dans tous les echantillons bimensuels preleves dans les lots fauches que dans les lots brules. Par exemple, pour le premier prelevement (24 avril) ils ont ete de 0,064 adulte et 0,016 immature par drageon (xT, N = 5 repetitions de 25 drageons) pour les lots brules contre 4,03 adultes et 1,08 immature pour les lots fauches. Les poids moyens de drageons et de graines recoltees etaient significativement plus eleves (P < 0,05) dans les lots brules. Dans des experiences au laboratoire, la hauteur et le poids des plantes etaient significativement inferieurs dans les lots artificiellement contamines avec des acariens par rapport aux temoins sains. A la fin de l'experience, 5 semaines apres la contamination, la hauteur moyenne etait de 16,48 cm dans les lots contamines (N = 40) contre 20,04 cm dans les temoins; de měme les poids etaient respectivement de 0,118 g et 0,187 g par drageon. Ces experiences prouvent que ces especes reduisent le poids et la hauteur des plantes. Nous estimons que le brulage des sols apres recolte peut diminuer les pertes en reduisant les populations hivernantes.
Global sensitivity analysis for DSMC simulations of hypersonic shocks

Abstract Two global, Monte Carlo based sensitivity analyses were performed to determine which reaction rates most affect the results of Direct Simulation Monte Carlo (DSMC) simulations for a hypersonic shock in five-species air. The DSMC code was written and optimized with shock tube simulations in mind, and includes modifications to allow for the efficient simulation of a 1D hypersonic shock. The TCE model is used to convert Arrhenius-form reaction rate constants into reaction cross-sections, after modification to allow accurate modeling of reactions with arbitrarily large rates relative to the VHS collision rate. The square of the Pearson correlation coefficient was used as the measure for sensitivity in the first of the analyses, and the mutual information was used as the measure in the second. The quantity of interest (QoI) for these analyses was the NO density profile across a 1D shock at ∼8000 m/s (M ∞ ≈ 23). This vector QoI was broken into a set of scalar QoIs, each representing the density of NO at a specific point downstream of the shock, and sensitivities were calculated for each scalar QoI based on both measures of sensitivity. Profiles of sensitivity vs. location downstream of the shock were then integrated to determine an overall sensitivity for each reaction. A weighting function was used in the integration in order to emphasize sensitivities in the region of greatest thermal and chemical non-equilibrium. Both sensitivity analysis methods agree on the six reactions which most strongly affect the density of NO. These six reactions are the N 2 dissociation reaction N 2 + N ⇄ 3N, the O 2 dissociation reaction O 2 + O ⇄ 3O, the NO dissociation reactions NO + N ⇄ 2N + O and NO + O ⇄ N + 2O, and the exchange reactions N 2 + O ⇄ NO + N and NO + O ⇄ O 2 + N. This analysis lays the groundwork for the application of Bayesian statistical methods for the calibration of parameters relevant to modeling a hypersonic shock layer with the DSMC method.
Optimizing geologic CO2 sequestration by injection in deep saline formations below oil reservoirs

Abstract The purpose of this research is to present a best-case paradigm for geologic CO 2 storage: CO 2 injection and sequestration in saline formations below oil reservoirs. This includes the saline-only section below the oil–water contact (OWC) in oil reservoirs, a storage target neglected in many current storage capacity assessments. This also includes saline aquifers (high porosity and permeability formations) immediately below oil-bearing formations. While this is a very specific injection target, we contend that most, if not all, oil-bearing basins in the US contain a great volume of such strata, and represent a rather large CO 2 storage capacity option. We hypothesize that these are the best storage targets in those basins. The purpose of this research is to evaluate this hypothesis. We quantitatively compared CO 2 behavior in oil reservoirs and brine formations by examining the thermophysical properties of CO 2 , CO 2 –brine, and CO 2 –oil in various pressure, temperature, and salinity conditions. In addition, we compared the distribution of gravity number ( N ), which characterizes a tendency towards buoyancy-driven CO 2 migration, and mobility ratio ( M ), which characterizes the impeded CO 2 migration, in oil reservoirs and brine formations. Our research suggests competing advantages and disadvantages of CO 2 injection in oil reservoirs vs. brine formations: (1) CO 2 solubility in oil is significantly greater than in brine (over 30 times); (2) the tendency of buoyancy-driven CO 2 migration is smaller in oil reservoirs because density contrast between oil and CO 2 is smaller than it between brine and oil (the approximate density contrast between CO 2 and crude oil is ∼100 kg/m 3 and between CO 2 and brine is ∼350 kg/m 3 ); (3) the increased density of oil and brine due to the CO 2 dissolution is not significant (about 7–15 kg/m 3 ); (4) the viscosity reduction of oil due to CO 2 dissolution is significant (from 5790 to 98 mPa s). We compared these competing properties and processes by performing numerical simulations. Results suggest that deep saline CO 2 injection immediately below oil formations reduces buoyancy-driven CO 2 migration and, at the same time, minimizes the amount of mobile CO 2 compared to conventional deep saline CO 2 injection (i.e., CO 2 injection into brine formations not below oil-bearing strata). Finally, to investigate practical aspects and field applications of this injection paradigm, we characterized oil-bearing formations and their thickness (capacity) as a component of the Southwest Regional Partnership on Carbon Sequestration (SWP) field deployments. The field-testing program includes specific sites in Utah, New Mexico, Wyoming, and western Texas of the United States.
Development of an SMA electrode to match type 316LN base metal cryogenic properties

Abstract A series of shielded metal arc electrodes was fabricated and the mechanical properties of the resultant welds were measured. The compositions are based on a high Mn, high N version of a type 308 electrode, to which additional Mn, N, Ni and Mo were added. The strength was measured at 4, 76 and 298 K, and the Charpy V-notch absorbed energy was measured at 76 K. The strength of the welds matched or exceeded that strength of the base metal, but fell short of the Charpy V-notch absorbed energy.
Seizures and tissue injury induce telomerase in hippocampal microglial cells

Telomerase is a reverse transcriptase that adds repeats of a six-base DNA sequence to chromosome ends and thereby prevents their shortening during successive cell divisions. Telomerase activity and expression of the catalytic subunit of telomerase (TERT) are high in brain cells during embryonic development, but are undetectable in the adult. We now report that telomerase activity and expression of TERT are induced in the hippocampus of adult mice after administration of the seizure-inducing excitotoxin kainate. Telomerase activity is present at 24 h and 7 days after kainate administration, but is no longer detectable at 4 weeks. Because the time course of telomerase induction was similar to the time course of microglial activation, we performed studies to determine whether microglia were the source of the telomerase activity. Examination of brain sections immunostained with a TERT antibody and an antibody against a microglia-specific antigen revealed that TERT was not detectable in the uninjured brain, and was present in microglia 24 h and 7 days after kainate administration. This is the first evidence that telomerase can be induced by brain injury and the first evidence that TERT can be expressed in microglia, suggesting roles for telomerase in microglial responses to brain injury.
Rectal water transport in vivo in the cockroach, Leucophaea maderae: tritiated water uptake and solute effects.

Abstract An in vivo perfusion technique with tritiated water was used to study the efflux of rectal lumen water and the influx of haemolymph water in the cockroach, Leucophaea maderae . No isotopic effects on tritiated water absorption through the rectal wall were observed. Concentrations of a non-diffusible solute trehalose ranging from 0·15 to 0·6 M did not differ in their effect on absorption of initial lumen water which was very rapid in the first 30 min. Influx of unlabelled haemolymph or tissue water was also rapid, preventing any net reductions in lumen volume in this time. When no solutes were perfused into the lumen, absorption was increased but influx of water still occurred at a reduced rate, apparently against a concentration gradient. The rapid turnover and cycling of water through the rectal wall and chamber in contrast to the long time necessary to dry the faecal pellet may be a way to facilitate reabsorption of small, metabolically useful, solute molecules including amino acids and monosaccharides filtered from the haemolymph by the Malpighian tubules or occurring as digestion residues. The process is relatively independent of a wide range of osmotic pressures in the lumen.
RADIOTOXICITY OF SYSTEMICALLY ADMINISTERED ( 211AT) ASTATIDE IN B6C3F1 AND BALB/c (NU/NU) MICE: A LONG-TERM SURVIVAL STUDY WITH HISTOLOGIC ANALYSIS

Abstract Purpose: The present study undertook to establish the dose (LD) of systemically administered (via tail vein) sodium [ 211 At]astatide that would kill 10% (LD 10 ) of exposed animals in two mouse models and to evaluate the resulting histologic lesions. Methods and Materials: Three dose escalation experiments were carried out using groups of 10 3- to 4-week-old, 20 ± 2 g B6C3F 1 mice, and one dose escalation experiment was carried out with groups of 10 4- to 6-week-old, 22 ± 2 g BALB/c (nu/nu) mice. All animals were weighed daily and checked twice daily for general health; autopsies were performed within 12 h of death. Results: The LD 10 (95% confidence interval) level of free [ 211 At]astatide at 360 days was 15.1 μCi (5.2–19.1 μCi) in B6C3F 1 mice and was associated with a 37.8% weight difference from saline controls ( p 10 at 360 days was 7.7 μCi (0–14.2 μCi), while a dose of 10 μCi (0.42 μCi g −1 ) was associated with a 9.44% weight difference vs. saline controls ( p 211 At]astatide activity levels were associated with severe bone marrow depression, testicular atrophy, focal alopecia, and nuclear atypia of the epidermoid mucosa of the fore-stomach in the B6C3F 1 mice; at activity levels approximating LD 10 at 360 days, mild changes in the heart, liver, stomach, and spleen were observed. For BALB/c (nu/nu) mice, administration of 10 μCi was associated at autopsy with mild histologic lesions in the heart, stomach, liver, and spleen. Conclusions: These studies provide a basis for the design of further investigations of [ 211 At]-labeled compounds as therapeutic agents.
Comparisons of different stages of chick embryonic development by the physiological regulatory response to hyposmotic challenge.

Abstract Cardiac myocytes isolated and cultured from 11 day chick embryos present a Ca 2+ -dependent regulatory volume decrease (RVD) when exposed to hyposmotic stimulus. The RVD of myocytes from different embryonic stages were analyzed to evaluate their physiological performance through development. Among the several embryonic stages analyzed (6, 11, 16 and 19 days) only 19 day cardiac myocytes present a greater RVD when compared with 11 day (considered as control), the other ages showed no difference in the regulatory response. As it is known that RVD is Ca 2+ dependent, we decided to investigate the transient free Ca 2+ response during the hyposmotic swelling of the 11 and 19 day stages. The 11 day cardiac myocyte showed a transient 40% increase in intracellular free Ca 2+ when submitted to hyposmotic solutions, and the free Ca 2+ returned to baseline levels while the cells remained in hyposmotic buffer. However, the intracellular free Ca 2+ transient in the 19 day cells during hyposmotic challenge increases 100% and instead of returning to baseline levels, declines to 55% above control, well after the 11 day transient has returned to baseline. Also, quantitative fluorescence microscopy revealed that 19 day cardiac myocytes have more sarcoplasmic reticulum (SR) Ca 2+ ATPase sites per cell as compared to the 11 day cells. Our findings suggest that 19 day cells have more developed intracellular Ca 2+ stores (SR). By evoking the mechanism of Ca 2+ induced Ca 2+ release, the cells have more free Ca 2+ available for signaling the RVD during hyposmotic swelling.
Survey of Fusarium species for plasmid-like DNA and some evidence for its occurrence in a strain of F. merismoides

Twenty-three strains representing thirteen species of Fusarium have been screened for the presence of plasmid-like DNA. Only one strain of F. merismoides showed evidence for the presence of this material, which could be extracted both from whole mycelium and from a preparation of intact mitochondria. It sedimented with mitochondrial DNA in caesium chloride gradients, and neither intercalating agents nor sodium dodecylsulphate were effective in eliminating it from growing mycelium.
Characterization of heavy petroleum feedstocks

Characterization of key heavy petroleum feedstock properties is important for optimizing the production of clean transportation fuels. A correlation-based method has been developed to accurately estimate the aromatic carbon and total hydrogen content of heavy petroleum feedstocks. The new characterization methodology is significantly superior to existing methods in that it is applicable to all types of heavy petroleum feedstocks, uses only two (most) commonly measured bulk petroleum properties and is more accurate. The new method has been validated via analysis of an unprecedented number (three hundred and fifty four) of heavy petroleum feedstocks with an extremely broad range of properties.
GABAmimetics: A New Class of Antidepressant Agents?

To the Editor.— We report a case study of an antidepressant action of progabide, a ɣ-aminobutyric acid (GABA) agonist, in a patient previously unresponsive to other antidepressant drug therapies. To our knowledge, selective GABA agonists have not been previously pursued as antidepressant therapies. Indeed, manipulation of monoaminergic neurotransmitter systems with tricyclic antidepressants or monoamine oxidase inhibitors has been the traditional therapeutic approach for depression.1However, serious side effects in some depressed patients and nonresponse in others have left many depressed individuals no pharmacological treatment options. In recent years both preclinical and some preliminary clinical studies have focused on the possible role of GABA in depression.2,3Since GABAmimetic therapy might have a different mechanism of neural action from current drugs, it would provide an important alternative treatment approach to depression. Report of a Case.— A 46-year-old woman had an 8-year history of major depressive disorder (DSM-III) associated
Role of HNF4α in the superinduction of the IL-1β-activated iNOS gene by oxidative stress

IL-1β (interleukin-1β) treatment of hepatocytes results in an NF-κB (nuclear factor-κB)-mediated activation of the iNOS (induced nitric oxide synthase) gene, and this increase in gene expression is further augmented by oxidative stress. Oxidative stress alone has no influence on the iNOS promoter, therefore indicating that the promoter needs to be primed by NF-κB. In this issue of the Biochemical Journal, Guo et al. extend their earlier work, showing that HNF4α (hepatocyte nuclear factor 4α) mediates the superinduction of iNOS observed by co-treating cells with IL-1β plus H2O2. A specific phosphorylation by p38 kinase at Ser-158 of HNF4α results in increased binding of HNF4α to the iNOS promoter, leading to enhanced transcription. The study by Guo et al. is the first to show definitively that HNF4α can be modulated to differentially activate specific genes. However, issues remain to determine the functional significance in vivo of the elevated iNOS activity, and the mechanism that governs the specificity of HNF4α towards the iNOS promoter element as compared with many other HNF4α target genes in the hepatocyte.
J.-F.-B. Charrière: The man behind the “French” gauge

Joseph-Frederic-Benoit Charriere, a 19th century Parisian maker of surgical instruments, has by virtue of his ingenuity and advanced thinking, continued to have his presence felt in medicine throughout the 20th century. His most significant accomplishment was the development of a uniform, standard gauge specifically designed for use in medical equipment such as catheters and probes. Unlike the gauge system adopted by the British for measurement of needles and intravenous catheters, Charriere's system has uniform increments between gauge sizes (1/3 of a millimeter), is easily calculated in terms of its metric equivalent, and has no arbitrary upper end point. Today, in the United States, this system is commonly referred to as French (Fr) sizing. In addition to the development of the French gauge, Charriere made significant advances in ether administration, urologic, and other surgical instruments, and the development of the modern syringe.
The economics of canola production by limited-resource farmers in South Carolina

ABSTRACT The purpose of this study is to examine the economic viability of canola production as an additional or alternative crop for limited-resource fanners in South Carolina, and to investigate the economics of its production as a competing rapeseed and oil crop. Canola offers farmers an additional or alternative crop to fall-planted crops such as winter wheat. Canola seed is in demand because of its value as an input in canola oil and meal production which is referred to as “crush.” Canola oil has a variety of uses. It is used in salads, as cooking oil, and as baking and frying fats. The oil can be found in processed foods such as potato and corn chips, salad dressings, mayonnaise, baked goods, and candies. This puts canola in a strong position to compete with other vegetable oils made out of soybean, cottonseed, corn and sunflower seed. It is cholesterol-free and has a saturated fat content of 6 percent. This is the lowest saturated fat content among major vegetable oils on the market. South Carolina...
A Hierarchical Key-Insulated Signature Scheme in the CA Trust Model

In key-insulated cryptography, there are many private keys with different indexes and a single, fixed public key. When the trust model includes multiple Certification Authorities (CAs), it can be used to shorten the verification path and mitigate the damage caused by the compromise of a CA’s private key. Existing work requires that the total number of CAs be fixed and that a trusted keystore store all private keys. This paper presents a hierarchical key-insulated signature scheme, called HKI, which converts existing key-insulated methods to a hierarchical scheme. Our scheme allows the system to repeatedly generate a new private key for a new CA and also provides two important features, namely a shortened verification path and mitigated damage. By basing our approach on a general key-insulated scheme, we have made it possible to take advantage of any future improvements in computation complexity, key length, or robustness in current key-insulated methods.
A Method for Detection and Classification of Events in Neural Activity

We present a method for the real time prediction of punctuate events in neural activity, based on the time-frequency spectrum of the signal, applicable both to continuous processes like local field potentials (LFPs) as well as to spike trains. We test it on recordings of LFP and spiking activity acquired previously from the lateral intraparietal area (LIP) of macaque monkeys performing a memory-saccade task. In contrast to earlier work, where trials with known start times were classified, our method detects and classifies trials directly from the data. It provides a means to quantitatively compare and contrast the content of LFP signals and spike trains: we find that the detector performance based on the LFP matches the performance based on spike rates. The method should find application in the development of neural prosthetics based on the LFP signal. Our approach uses a new feature vector, which we call the 2d cepstrum
Chemical and Seasonal Controls on the Dynamics of Dissolved Organic Matter in a Coniferous Old-growth Stand in the Pacific Northwest, USA

Soil organic matter (SOM) is the largest terrestrial C pool, and retention and release of dissolved organic matter (DOM) cause formation and loss of SOM. However, we lack information on how different sources of DOM affect its chemical composition, and how DOM chemical composition affects retention. We studied seasonal controls on DOM production and chemical controls on retention in soils of a temperate coniferous forest. The O horizon was not usually the dominant source for dissolved organic C (DOC) or N (DON) as has been reported for other sites. Rather, net production of both DOC and DON was often greater in the shallow mineral soil (0-10 cm) than in the O horizon. DOM production in the shallow mineral soil may be from root exudation as well as turnover of fine roots and microflora in the rhizosphere. In the field, the two acid fractions (hydrophobic and hydrophilic acids) dominated the soil solution at all depths. A major portion of net production and removal of total DOC within the soil column was explained by increases and decreases in these fractions, although a shift in chemical composition of DOM between the O and mineral soil horizons suggested different origins of DOM in these layers. A larger loss of the free amino fraction to deep soil water at this study site than at other sites suggested lower retention of labile DON. Field DOM removal measurements suggest that field-measured parameters may provide a good estimate for total DOM retained in mineral soil.
Empirical regularities from interacting long- and short-memory investors in an agent-based stock market

This paper explores some of the empirical features generated in an agent-based computational stock market with market participants adapting and evolving over time. Investors view differing lengths of past information as being relevant to their investment decision-making process. The interaction of these memory lengths in determining market prices creates a kind of market ecology in which it is difficult for the more stable longer horizon agents to take over the market. What occurs is a dynamically changing market in which different types of agents arrive and depart depending on their current relative performance. This paper analyzes several key time series features of such a market. It is calibrated to the variability and growth of dividend payments in the United States. The market generates some features that are remarkably similar to those from actual data. These include magnifying the volatility from the dividend process, inducing persistence in volatility and volume, and generating fat-tailed return distributions.
Clinical Features of Complications From Transesophageal Echocardiography: A Single-Center Case Series of 10,000 Consecutive Examinations

Background Transesophageal echocardiography (TEE) is an essential diagnostic tool that has gained widespread use in clinical cardiology. It is considered reasonably noninvasive and safe; however, insertion and operation of the TEE probe may cause hypopharyngeal, esophageal, or gastric trauma. The current study reports a single-center experience of esophagogastric trauma in 10,000 consecutive TEE examinations. Methods TEE examinations were performed by 9 attending physicians who were trained in endoscopic procedures and had been performing TEE studies for at least 1 year. Results One case of hypopharyngeal perforation (0.01%), 2 cases of cervical esophageal perforation (0.02%), and no cases of gastric perforation (0%) occurred after TEE examination. No fatalities (0%) occurred. We describe the clinical characteristics of individuals who experienced esophageal perforation during this 10-year period. Conclusions This single-center study demonstrates that TEE examinations are associated with a very low risk of esophagogastric trauma when performed in a safe setting by experienced operators.
Development of a Unique Triage System for Acute Care Physical Therapy and Occupational Therapy Services: An Administrative Case Report

Background and Purpose This administrative case report documents the development of a mechanism by which systematic triage was used to assign patients to therapists in acute care settings. The primary objective was to develop a triage tool to improve patient access to medically necessary therapy services. Case Description A unique triage tool and a decision tree were developed to determine which patients referred to therapists for acute care therapy required skilled services. The triage tool was used to examine therapy referrals for patients from 2 large academic hospitals; 6 criteria were used to determine which evaluations should be cancelled. During the trial period, the predictive ability of individual triage criterion items was analyzed, the tool was modified and validated, and a decision tree was established. Descriptive and chi-square analyses were performed on all variables of interest. Outcomes The systematic triage system reduced the number of therapy evaluations that were not appropriate by 29%, resulting in an improvement in the availability of therapy services for patients who required skilled care. The average number of patients per therapist per workday decreased from 18.9 to 12.1 and from 15.1 to 12.8 in the 2 hospitals. An improvement in a newly developed “workload index” related to missed patient visits also indicated the success of this project. Discussion A novel systematic triage system reduced the number of therapy evaluations that were not appropriate, resulting in an improvement in the availability of therapy services for patients who require skilled intervention.