cssi/SciSciGPT-SciSciNet huggingface dataset:
13C and 1H NMR ester region resonance assignments and the composition of human infant and child meibum.

Recent NMR studies suggest that unsaturation may contribute to tear film instability in adults and loss of cholesteryl esters and squalene could reduce tear film stability in adults with meibomian gland dysfunction. The proton resonances were tentatively assigned in those studies. In this current investigation, meibum from seven infants and children, one adult and a pool of adult meibum have been analyzed using an NMR spectrometer with greater sensitivity and spectral resolution. The goals of this work are to confirm/correct the previous assignments and to determine possible age-related changes in composition. The initial resonance assignments were confirmed using heteronuclear single quantum correlation spectroscopy. Because there were no significant interferences in the spectral region corresponding to the resonances for cholesteryl and wax esters, the areas of these resonances were used to calculate their molar ratios. We calculated a wax ester:cholesteryl ester molar ratio of 1:0.57 ± 0.05 for all our meibum samples and there were no age-related differences. At lower film thicknesses, the rate of evaporation measured in vitro was lower for wax esters mixed with a long chain cholesteryl ester compared to wax esters alone. However, the film thicknesses tested were non-physiological. Longer chain cholesteryl esters increase the interactions between hydrocarbon chains. Hydrocarbon chains were more saturated in meibum from infants and children compared to adults. Unsaturation may contribute to tear film instability in adults. Loss of cholesteryl ester and squalene could destabilize tear film in adults with meibomian gland dysfunction.
Evolution of Atlantic thermohaline circulation: Early Oligocene onset of deep-water production in the North Atlantic

The flow of deep-water masses is a key component of heat transport in the modern climate system, yet the role of deep-ocean heat transport during periods of extreme warmth is poorly understood. The present mode of meridional overturning circulation is characterized by deep-water formation in both the North Atlantic and the Southern Ocean. However, a different mode of meridional overturning circulation operated during the extreme greenhouse warmth of the early Cenozoic, during which time the Southern Ocean was the dominant region of deep-water formation. The combination of general global cooling and tectonic evolution of the Atlantic basins over the past ∼55 m.y. ultimately led to the development of a mode of overturning circulation characterized by both Southern Ocean and North Atlantic deep-water sources. The change in deep-water circulation mode may, in turn, have affected global climate; however, unraveling the causes and consequences of this transition requires a better understanding of the timing of the transition. New Nd isotope data from the southeastern Atlantic Ocean indicate that the initial transition to a bipolar mode of deep-water circulation occurred in the early Oligocene, ca. 33 Ma. The likely cause of significant deep-water production in the North Atlantic was tectonic deepening of the sill separating the Greenland-Norwegian Sea from the North Atlantic.
Determination of nucleotide sequences in soluble ribonucleic acid I. Pycrophosphorolysis and reconstitution of a fraction of soluble ribonucleic acid

Abstract After two successive treatment of liver soluble RNA with pyrophosphate and the enzyme that incorporates nucleotides into terminal positions of soluble RNA, little further enhancement of CMP incorporation is observed. It is concluded from this that pyrophosphorolysis of the soluble RNA is almost complete after two such treatments. Pyrophosphate treatment of soluble RNA which has radioctive amino acids bound to it does not remove the amino acids, and the results of a related experiment show that this treatment does not remove CMP from soluble RNA chains which have amino acids bound to them. More than 95% of the radioactivity which appears in the acid-soluble fraction during purophosphorolysis of soluble RNA with [su32P]pyrophosphate is in ATP and CTP. The amounts of labelled CTP and ATP which appear under these conditions are roughly equal to the amounts of CMP and AMP, respectively, which can be re-incorporated into the pyrophosphorolyzed soluble RNA. Pyrophosphorolysis of liver soluble RNA reduces its capacity to accept threonine and tyrosine to 30% of that of the untreated soluble RNA. This capacity can be almost completely restored by pre-incubating the pyrophosphorolyzed soluble RNA with ATP, CTP and the nucleotide-incorporating enzyme system.
The Milgram obedience experiment: support for a cognitive view of defensive attribution.

(1996). The Milgram Obedience Experiment: Support for a Cognitive View of Defensive Attribution. The Journal of Social Psychology: Vol. 136, No. 3, pp. 407-410.
Stable, high‐affinity streptavidin monomer for protein labeling and monovalent biotin detection

The coupling between the quaternary structure, stability and function of streptavidin makes it difficult to engineer a stable, high affinity monomer for biotechnology applications. For example, the binding pocket of streptavidin tetramer is comprised of residues from multiple subunits, which cannot be replicated in a single domain protein. However, rhizavidin from Rhizobium etli was recently shown to bind biotin with high affinity as a dimer without the hydrophobic tryptophan lid donated by an adjacent subunit. In particular, the binding site of rhizavidin uses residues from a single subunit to interact with bound biotin. We therefore postulated that replacing the binding site residues of streptavidin monomer with corresponding rhizavidin residues would lead to the design of a high affinity monomer useful for biotechnology applications. Here, we report the construction and characterization of a structural monomer, mSA, which combines the streptavidin and rhizavidin sequences to achieve optimized biophysical properties. First, the biotin affinity of mSA (K(d) = 2.8 nM) is the highest among nontetrameric streptavidin, allowing sensitive monovalent detection of biotinylated ligands. The monomer also has significantly higher stability (T(m) = 59.8 °C) and solubility than all other previously engineered monomers to ensure the molecule remains folded and functional during its application. Using fluorescence correlation spectroscopy, we show that mSA binds biotinylated targets as a monomer. We also show that the molecule can be used as a genetic tag to introduce biotin binding capability to a heterologous protein. For example, recombinantly fusing the monomer to a cell surface receptor allows direct labeling and imaging of transfected cells using biotinylated fluorophores. A stable and functional streptavidin monomer, such as mSA, should be a useful reagent for designing novel detection systems based on monovalent biotin interaction.
Sparse Expansions Using Physical and Polynomial Basis Functions for Compressed Sensing of Frequency Domain EM Scattering

A scattering center model is proposed for providing a very efficient sparse expansion for radar scattering data based on physical and polynomial functions to represent the frequency dependence of the amplitude. Simple scattering centers are very inefficient in situations where a low residual error is needed in reconstructing the data from the sparse expansion. It is shown that the new approach overcomes errors associated with grid mismatch, overlapping scattering centers, and model discrepancies. Compressed sensing is applied to extract the sparse expansion with a greatly reduced set of samples. Convergence of the sparse expansion is demonstrated for selected targets.
Macular vitelliform lesion in desferrioxamine-related retinopathy

To report a case of a macular vitelliform lesion associated with desferrioxamine treatment. Ocular, electrophysiological, psychophysical, perimetric, fluorescein angiographic, fundus autofluorescence, and spectral-domain OCT examinations were obtained on a 45-year-old Caucasian woman with thalassemia major treated with blood transfusions and desferrioxamine. The patient was observed to have a vitelliform macular lesion in the right eye with a hypopigmented macular lesion and retinal pigment mottling in the left. At the most recent follow-up visit, best-corrected visual acuity was 20/70 in the right eye and 20/25 in left. Full-field electroretinogram (ERG) testing showed normal cone and rod responses. Mild localized elevations of rod psychophysical thresholds were found. A vitelliform macular lesion can develop in patients treated with desferrioxamine. Some such patients may not show diffuse photoreceptor cell functional loss as determined by electrophysiological testing.
Equilibrium-Based Movement Endpoints Elicited from Primary Motor Cortex Using Repetitive Microstimulation

High-frequency, long-duration intracortical microstimulation (HFLD-ICMS) is increasingly being used to deduce how the brain encodes coordinated muscle activity and movement. However, the full movement repertoire that can be elicited from the forelimb representation of primary motor cortex (M1) using this method has not been systematically determined. Our goal was to acquire a comprehensive M1 forelimb representational map of movement endpoints elicited with HFLD-ICMS, using stimulus parameters optimal for evoking stable forelimb spatial endpoints. The data reveal a 3D forelimb movement endpoint workspace that is represented in a patchwork fashion on the 2D M1 cortical surface. Although cortical maps of movement endpoints appear quite disorderly with respect to movement space, we show that the endpoint locations in the workspace evoked with HFLD-ICMS of two adjacent cortical points are closer together than would be expected if the organization were random. Although there were few obvious consistencies in the endpoint maps across the two monkeys tested, one notable exception was endpoints bringing the hand to the mouth, which was located at the boundary between the hand and face representation. Endpoints at the extremes of the monkey's workspace and locations above the head were largely absent. Our movement endpoints are best explained as resulting from coactivation of agonist and antagonist muscles driving the joints toward equilibrium positions determined by the length–tension relationships of the muscles.
TP-A1 enhancement of effective barrier height in a Ti-silicon Schottky diode using low-energy ion implantation

Increasing the effective barrier height in a Ti-p-type silicon Schottky diode has been achieved by means of low-energy ion implantation to introduce a thin inversion layer on silicon substrate. It is shown theoretically that effective barrier height equal to the energy bandgap can be obtained in such structure if the thickness and dopant density of the implanted layer are properly chosen. Experimental results for several titanium (Ti) on phosphorus implanted p-type silicon Schottky diodes show that effective barrier heights were increased from 0.6 eV for the Ti-p Si Schottky diode to 0.96 eV for a Ti-n-p-Si Schottky diode with a phosphorus-implanted layer thickness of 400 A and dose of 1.26 × 1012cm-2. Good agreement is obtained between the calculated and the measured barrier height for several Ti-n-p silicon Schottky diodes.
Academic HTS: diverse portraits

High-throughput screening (HTS) centers have been established at many universities over the past five years. The characteristics of academic HTS centers vary widely. They generally have smaller compound collections, less automation and less software than their industrial counterparts. Academic HTS centers have had success in finding biological probes, and many of their contributions are documented in the scientific literature.
Use of cholestyramine in the treatment of children with familial combined hyperlipidemia

We studied the effectiveness of and compllance with the use of cholestyramine in children with heterozygous familial hypercholesterolemia (FH) and familial combined hyperlipidemia (FCHL). During a 10-year period, 673 children (aged 10.5±4.0 years) were referred for evaluation of hyperlipidemia, of whom 87 (36 with FH; 51 with FCHL) were treated with cholestyramine (8 to 24 gm/day). In both groups, total cholesterol, low-density lipoprotein (LDL)-cholesterol, and apoli-poprotein B levels were significantly reduced after cholestyramine use. In those with FH, plasma LDL-cholesterol levels decreased from 258±35 mg/dl (6.67±0.90 mmol/L) to 190±31 mg/dl (4.91±0.80 mmol/L); in those with FCHL, LDL-cholesterol levels dropped from 207±40 mg/dl (5.35±1.03 mmol/L) to 141±35 mg/dl (3.64±0.90 mmol/L). High-density lipoprotein-cholesterol levels were not significantly changed after cholestyramine use in either group. In the FCHL group, plasma triglyceride levels increased significantly from 81±35 mg/dl (0.92±0.40 mmol/L) to 134±42 mg/dl (1.52±0.48 mmol/L). Seven patients were lost to follow-up; 18 discontinued the medication within 1 month. Of the remaining 62 children, 59 had a good response to the drug. Of the 62 patients, 52 discontinued the medication after 21.9±10 months. Adverse effects included foul taste (73%), nausea with bloating (18%), and constipation. Cholestyramine is effective in reducing LDL-cholesterol levels in children with inherited hyperlipidemia, but the majority of children will not comply with its long-term use.
Instance based learning with automatic feature selection applied to word sense disambiguation

We describe an algorithm for Word Sense Disambiguation (WSD) that relies on a lazy learner improved with automatic feature selection. The algorithm was implemented in a system that achieves excellent performance on the set of data released during the SENSEVAL-2 competition. We present the results obtained and discuss the performance of various features in the context of supervised learning algorithms for WSD.
Wave mixing and amplified spontaneous emission in pure potassium and mixed sodium-potassium vapors

We report observations of several wave-mixing and stimulated processes in pure potassium and mixed sodium-potassium vapors which are excited by a pulsed laser operating in the range 680–800 nm. When the laser is tuned to the potassium two-photon 4S→6S transition, we observe stimulated emission on the various cascade transitions as well as four- and six-wave mixing. When the laser is tuned over the range 747 to 753 nm, which is well away from all atomic transitions, we observe strong forward and weak backward emission at the potassium 3D3/2→4P1/2 transition wavelength (1.17 μm). However, this latter emission is only observed in the mixed sodium-potassium vapor. We present data on the excitation spectrum, forward to backward asymmetry, temporal dependence, and the laser power dependence of this emission. We speculate that twophoton photodissociation of the NaK molecule is responsible for this emission.
Coronary Artery Vasculitis as a Presentation of Cardiac Sarcoidosis

A 40-year-old white man was admitted for excision of a subcutaneous lesion on his torso. He reported a 12-month history of shortness of breath and exertional chest pain, both of which were relieved by rest. The patient was otherwise asymptomatic, and physical examination was noncontributory. He was not taking any medications. Electrocardiographic monitoring during the procedure revealed third-degree heart block with junctional escape and right bundle-branch block at 38 bpm (Figure 1). The patient was hemodynamically stable. An electrophysiology consultation was requested, and the patient was found to have an elevated serum angiotensin-converting enzyme level. Histological examination of the biopsy specimen showed noncaseating granulomata, which confirmed the diagnosis of sarcoidosis. Figure 1. Twelve-lead ECG taken 8 minutes after procedure while the patient was in recovery. This shows third-degree heart block with right bundle-branch block …
Short-term follow-up of patients with sickle cell disease and albuminuria.

Background Albuminuria with normal serum creatinine occurs frequently in patients with sickle cell disease (SCD), but the rate of progression to more advanced chronic renal disease is unknown. The purpose of this study was to investigate the rate of progression of children and young adults with SCD and albuminuria over time. Procedure Urine albumin/creatinine (A/C) ratios and serum creatinine were obtained serially. Serum cystatin C levels were determined in a subgroup of 20 patients. Results Of 38 patients with SCD who had albuminuria (30 with microalbuminuria and 8 with proteinuria), 10.5% had progressive disease during follow-up of 20 ± 12 months. Progressive disease was observed in 2 of 30 patients with MA because MA worsened to either intermittent proteinuria (1 patient), or persistent proteinuria after 7 months follow-up (1 patient). Two of eight patients with proteinuria worsened to nephrotic-range after 8 and 17 months with elevations of serum creatinine. All eight patients with proteinuria were treated with angiotensin blockade and/or hydroxyurea. Of those, six patients responded to treatment with decreased albuminuria and no changes in serum creatinine. Serum cystatin C level trended to increase before serum creatinine in patients with proteinuria. Conclusions Patients with rapid progression to nephrotic-range proteinuria showed decreased kidney function. Therefore, patients with albuminuria should be monitored closely for progression, and therapy with hydroxyurea and/or angiotensin blockade should be considered for patients who develop proteinuria. Serum cystatin C appears more sensitive than serum creatinine to detect early decrease in kidney function. Pediatr Blood Cancer 2008;50:1236–1239. © 2008 Wiley-Liss, Inc.
Detection of brief light flashes by monkeys (Macaca nemestrina) with dorsolateral frontal ablations.

Abstract Four female pigtail monkeys with dorsolateral frontal ablations and four unoperated controls were tested on their ability to detect brief light flashes from a sixteen-panel matrix. Flashes were varied in their location, duration ( 1 15 , 1 8 , 1 4 , or 1 2 sec ) , presence or absence of a subsequent masking flash. The interval between the initial light flash and subsequent masking flash occurred at intervals of 4, 8, 15, and 30 msec. Performance by frontal subjects was inferior to that of controls. The deficit, however, was not related to either flash duration or interval of the subsequent masking flash. Close visual observation during testing did nor reveal any difference in visual or postural orientation to the testing apparatus. Analysis of response patterns indicated that subjects with frontal ablations committed more errors on trials illuminating center panels than corner panels, and also were more likely to commit nonadjacent than adjacent errors. The results were discussed in terms of decreased capacity to process information.
Mariner 9 photographs of small volcanic structures on Mars

Surface features on the flanks of Martian shield volcanoes photographed by Mariner 9 are identified as lava flow channels, rift zones, and partly collapsed lava tubes by comparisons with similar structures on the flanks of Mauna Loa shield volcano, Hawaii. From these identifications, the composition of the Martian lava flows is interpreted to be basaltic, with viscosities ranging from those of fluid pahoehoe to more viscous aa.
In Depth Exploration of the Hemolymph of Limulus polyphemus via Combinatorial Peptide Ligand Libraries

The hemolymph of Limulus polyphemus, a very ancient marine arthropod dating back to ca. 440 million years, has been explored in depth via capture by combinatorial peptide ligand libraries. Whereas barely a dozen proteins had been known up to the present, we have increased this number by more than 1 order of magnitude, up to 160 unique gene products, identified via the dbEST_limulus as well as via comparison with the other members of the Chelicerata subphylum to which Limulus belongs, namely, scorpions, ticks, mites, and spiders. Yet we have sequences of many other peptides, suggesting the presence of at least one more order of magnitude of species (1000 and more), that could not be identified as such sequences have no counterparts in present databases. This further reinforces the notion that these could be ancestral proteins, scarcely represented in present times. These data might represent the true birth of paleo-proteomics.
The Jesuit Difference (?): Narratives of Negotiating Spiritual Values and Secular Practices

ABSTRACT We detail the experiences of a department of six faculty members in negotiating spirituality in a Jesuit, Catholic University. Grounding our work in “co-constructed narrative” as a method, we utilize narratives gathered through self-reflection, conversation, and interviews to elucidate how contradictory conditions are created through competing discourses of spiritual values and secular practices. These competing discourses create tensions of (a) embracing/resisting, (b) inclusion/exclusion, and (c) proclamation/silence. Faculty narratives revealed the ways they frame and negotiate these tensions in their attempts to construct their identities in relation to the organization and its values. Dialogic theory (Bahktin, 1981 1986 1993) is utilized to interpret faculty narratives as well as offer new directions for organizational communication theorizing.
Actuation of elastomeric microvalves in point-of-care settings using handheld, battery-powered instrumentation.

Although advanced fluid handling using elastomeric valves is useful for a variety of lab-on-a-chip procedures, their operation has traditionally relied on external laboratory infrastructure (such as gas tanks, computers, and ground electricity). This dependence has held back the use of elastomeric microvalves for point-of-care settings. Here, we demonstrate that microfabricated microvalves, via liquid-filled control channels, can be actuated using only a handheld instrument powered by a 9 V battery. This setup can achieve on–off fluid control with fast response times, coordinated switching of multiple valves, and operation of a biological assay. In the future, this technique may enable the widely used elastomeric microvalves (made by multilayer soft lithography) to be increasingly adopted for portable sensors and lab-on-a-chip systems.
Experiments for first year engineering students using tin-bismuth alloys

Introductory courses, whether at the freshman or junior level, are frequently based on the paradigm that processing affects structure, which affects properties, which, in turn, determine performance, and is the basis for design. Once this is understood by the students, it is possible to have them make design decisions based on experimental data and have them identify alternative materials using the paradigm. This paper describes a series of experiments and demonstrations that can be incorporated into an introductory materials course to help students appreciate how processing changes structure, which leads to a change in properties.
Divorce in Europe and the United States: Commonalities and differences across nations

Although the United States has the highest divorce rate of any Western nation, divorce rates have been increasing in almost all European countries. In this review, we compare studies conducted in the United States and Europe that focus on three topics: (1) the demographic and economic predictors of divorce, (2) the estimated effects of divorce on adults, and (3) the estimated effects of divorce on children. This task is complicated by the substantial degree of diversity that exists across Europe, with research findings often varying across countries. Despite this complexity, a great deal of similarity in the causes and consequences of divorce exists across countries. Nevertheless, more research that directly compares the United States with specific European nations would add greatly to our understanding of these phenomena.
Analysis of pea lipid content by gas chromatographic and microgravimetric methods. genotype variation in lipid content and fatty acid composition

Two methods were developed for the analysis of total lipid content in dried peas. The first measured total fatty acid methyl esters (total FAME) by gas chromatography. The second was a microgravimetric method. Both methods gave equally precise results with a skilled analyst but the total FAME method required less sample, was easier to use and was preferred for the analysis of large numbers of samples. Using the total FAME method a wide range of pea genotypes including primitive or wild forms, field peas, and round and wrinkled garden peas were analysed. The lipid content, expressed as percentage by weight, of dry whole pea flours prepared from 166 genotypes ranged from 1.4–4.0% and exhibited a bimodal distribution. The lower lipid population corresponded to round peas and the higher lipid population to wrinkled peas. Although only five fatty acids occurred in significant quantities in the total lipid there was considerable variation in their individual contents. In decreasing order of content, in the vast majority of genotypes, the fatty acids were linoleic (18:2), oleic (18:1), palmitic (16:0), linolenic (18:3) and stearic (18:0). In a few genotypes, however, oleic acid predominated over linoleic acid. Linolenic acid ranged from 2.5–14.9% of the total fatty acids. A positive linear correlation (r=0.98) was found to exist between total FAME values (LF) and corresponding gravimetric lipid values (LG) for a combined population of round and wrinkled peas. An initial calibration was derived by regression analysis of data obtained by the FAME method and a large scale gravimetric method. This was tested and found to give satisfactory prediction of LG on a second set of samples analysed by the FAME method and the microgravimetric method.
An assessment of systems analysis and design courses

Abstract Are colleges and universities adequately preparing their information systems graduates to perform successfully as practicing systems analysts? In this paper the relative importance of systems analysis and design tasks and skills as taught in undergraduate systems analysis and design courses is compared to the importance placed on these tasks and skills by practicing systems analysts. Whereas some concurrence is found, the number and nature of the differences may prompt educators to consider adjustments to the focus of their courses.
Transport of Steroid Hormones: Interaction of 70 Drugs with Testosterone-Binding Globulin and Corticosteroid-Binding Globulin in Human Plasma

This report describes the binding of 70 synthetic compounds to both testosterone-binding globulin (TeBG) and corticosteroid-binding globulin (CBG). The ability of each compound to displace [3H]testosterone from TeBG and [3H]cortisol from CBG adsorbed from a plasma pool onto a solid phase matrix of Concanavalin A-Sepharose was determined under equilibrium conditions at physiological pH and temperature. From these data, the association constants of the compounds for binding to both TeBG and CBG were calculated and used to predict whether endogenous steroid transport would be altered by the therapeutic administration of the drug. Computer simulation predicted that by interacting with TeBG, therapeutic levels of danazol, methyltestosterone, fluoxymesterone, and norgestrel could displace 83%, 48%, 43%, and 16%, respectively, of the concentration of testosterone bound to TeBG in a normal man. Similarly, by interacting with CBG, therapeutic levels of prednisolone could decrease the concentration of cortisol bound to CBG by approximately 32% in both men and women, and despite relatively low affinity binding to TeBG (5 X 10(5) M-1), prednisolone could also displace small amounts of testosterone from TeBG. These results indicate that binding to steroid transport proteins should be considered among the in vivo effects of drugs on endogenous steroid hormone levels.
A Decade Analysis of Trends and Outcomes of Partial Versus Total Esophagectomy in the United States

Objective:To examine the trends and outcomes of partial esophagectomy with an intrathoracic anastomosis compared with total esophagectomy with a cervical anastomosis.Background:Controversy exists regarding the optimal surgical approach in the management of esophageal cancer.Methods:Using the Nationw
Physicochemical effects of acidosis on bone calcium flux and surface ion composition

Net calcium flux (JCa) from bone in vitro is pH dependent. When pH falls below 7.40, through a reduction in [HCO3−], there is both physicochemical and cell-mediated JCa. To characterize the physicochemical effect of acidosis on bone we inhibited the bone-resorbing cells (osteoclasts) with the specific inhibitor calcitonin and studied the effect of acidosis on JCa and bone ion composition using an analytic high-resolution scanning ion microprobe. Neonatal mouse calvariae were cultured for 48 h in physiologically neutral pH medium (Ntl, pH = 7.41, [HCO3−] = 25 nM) or in medium that modeled metabolic acidosis (Met, pH = 7.10, [HCO3−] = 12), each with or without calcitonin (CT, 3 × 10−9 M). There was net calcium efflux in Ntl (JCa = 631 ± 36 nmol per bone per 48 h), which increased in Met (1019 ± 53, p < 0.01); CT inhibited JCa in Ntl (-54 ± 11, p < 0.01 versus Ntl), which increased in Met (197 ± 15, p < 0.01 versus Ntl + CT). In the presence of CT the increase in JCa in Met versus Ntl represents physicochemical bone dissolution. The Ntl bone surface (∼2 nm in depth) was rich in Na compared to Ca (Na/Ca = 11.9, counts/s of detected secondary ions), which fell in Met (Na/Ca = 6.0, p < 0.05); CT caused a further reduction of Na/Ca (3.1, p < 0.01 versus Ntl and versus Met), which was not altered in Met (2.6, p ≥ 0.05 versus Ntl + CT). The subsurface of the Ntl bone, eroded to a depth of = 100 nm with the microprobe, was also rich in Na/Ca (11.0), which fell in Met (4.1, p < 0.05); CT caused a further fall in Na/Ca (3.8, p < 0.01 versus Ntl), which again was not altered in Met (3.5, p ≥ 0.05 versus Ntl + CT). Acidosis causes a release of bone Ca and a fall in the ratio of bone Na/Ca, indicating a greater release of Na. Inhibition of osteoclastic function with calcitonin causes an influx of Ca to bone and a marked fall in bone Na/Ca, indicating little change in Na. Acidosis plus calcitonin causes Ca release with no change in Na/Ca, indicating that physicochemical bone mineral dissolution causes relatively equal Ca and Na release. Thus, the cell-mediated effect of acidosis-induced bone resorption appears responsible for the excess Na efflux.
Passive Microwave Spectral Emission from Saline Ice at C-Band During the Growth Phase

This paper focusses on microwave radiometer measurements of the emission from saline ice as a function of ice thickness. The instrument used is a C-band stepped-frequency microwave radiometer (SFMR) that can be tuned to operate at any center frequency from 4 to 8 GHz at a bandwidth of 100 MHz. The measurements were undertaken at a facility constructed by the U. S. Army Cold Regions Research and Engineering Laboratory, which was specifically designed to satisfy remote-sensing requirements. In addition to presenting the data, a simple theory is developed to explain the experimental results in terms of the relevant electromagnetic parameters; namely, the complex dielectric constant and thickness of the ice.
When can clades be potentially resolved with morphology

Morphology-based phylogenetic analyses are the only option for reconstructing relationships among extinct lineages, but often find support for conflicting hypotheses of relationships. The resulting lack of phylogenetic resolution is generally explained in terms of data quality and methodological issues, such as character selection. A previous suggestion is that sampling ancestral morphotaxa or sampling multiple taxa descended from a long-lived, unchanging lineage can also yield clades which have no opportunity to share synapomorphies. This lack of character information leads to a lack of ‘intrinsic’ resolution, an issue that cannot be solved with additional morphological data. It is unclear how often we should expect clades to be intrinsically resolvable in realistic circumstances, as intrinsic resolution must increase as taxonomic sampling decreases. Using branching simulations, I quantify intrinsic resolution across several models of morphological differentiation and taxonomic sampling. Intrinsically unresolvable clades are found to be relatively frequent in simulations of both extinct and living taxa under realistic sampling scenarios, implying that intrinsic resolution is an issue for morphology-based analyses of phylogeny. Simulations which vary the rates of sampling and differentiation were tested for their agreement to observed distributions of durations from well-sampled fossil records and also having high intrinsic resolution. This combination only occurs in those datasets when differentiation and sampling rates are both unrealistically high relative to branching and extinction rates. Thus, the poor phylogenetic resolution occasionally observed in morphological phylogenetics may result from a lack of intrinsic resolvability within groups.
Changing the Conversation About Brain Death

We seek to change the conversation about brain death by highlighting the distinction between brain death as a biological concept versus brain death as a legal status. The fact that brain death does not cohere with any biologically plausible definition of death has been known for decades. Nevertheless, this fact has not threatened the acceptance of brain death as a legal status that permits individuals to be treated as if they are dead. The similarities between "legally dead" and "legally blind" demonstrate how we may legitimately choose bright-line legal definitions that do not cohere with biological reality. Not only does this distinction bring conceptual coherence to the conversation about brain death, but it has practical implications as well. Once brain death is recognized as a social construction not grounded in biological reality, we create the possibility of changing the social construction in ways that may better serve both organ donors and recipients alike.
On the role of ‘habitual aborters’ in the analysis of spontaneous abortion

Analyses of spontaneous abortion rates often include special provisions to account for the presumed distorting effects that arise because of the presence of habitual aborters. In this paper, I establish a framework for investigating the effects of the presence in study groups of such women. I then examine the strengths and weaknesses of some of the analysis strategies in current use, both in situations where the study group is homogeneous and where there are high-risk women present. I show that the concept of habitual aborter is not useful and can be misleading, and I suggest that one take a broader view of heterogeneity.
Therapeutic potential of genetically modified mesenchymal stem cells

Bone marrow-derived mesenchymal stem cells (MSC) are multipotent adult stem cells of mesodermal origin localized within the bone marrow compartment. MSC possess multilineage property making them useful for a number of potential therapeutic applications. MSC can be isolated from the bone marrow, expanded in culture and genetically modified to serve as cell carriers for local or systemic therapy. Despite their ability to differentiate into osteoblasts, chondrocytes, adipocytes, myocytes and neuronal cells under appropriate stimuli, distinct molecular signals that guide migration of MSC to specific targets largely remain unknown. The pluripotent nature of MSC makes them ideal resources for regenerative medicine, graft-versus-host disease and autoimmune diseases. Despite their therapeutic potential in a variety of diseases, certain issues need to be critically addressed both in in vitro expansion of these cells without losing their stem cell properties, and the long-term fate of the transplanted MSC in vivo following ex vivo modifications. Finally, understanding of complex, multistep and multifactorial differentiation pathways from pluripotent stem cells to functional tissues will allow us to manipulate MSC for the formation of competent composite tissues in situ. The present article will provide comprehensive account of the characteristics of MSC, their isolation and culturing, multilineage properties and potential therapeutic applications.
A feedback control model for cortisol secretion

Existing mathematical models for cortisol secretion do not describe the entire cortisol secretion process, from the neural firing of corticotropin releasing hormone (CRH) in the hypothalamus to cortisol concentration in the plasma. In this paper, we lay the groundwork to construct a more comprehensive model, relating CRH, Adrenocorticotropic hormone (ACTH), and cortisol. We start with an existing mathematical model for cortisol secretion, and combine it with a simplified neural firing model that describes CRH and ACTH release. This simplified neural firing model is obtained using the extended FitzHugh-Nagumo (FHN) model, which includes a time-varying spiking threshold [3]. A key feature of our model is the presence of a feedback loop from cortisol secretion to ACTH secretion.
Personalized ranking in web databases: establishing and utilizing an appropriate workload

The emergence of the deep Web has given a new connotation to the concept of ranking database query results. Earlier approaches for ranking either resorted to analyzing frequencies of database values and query logs or establishing user profiles. In contrast, an integrated approach, based on the notion of a similarity model, for holistically supporting user- and query-dependent ranking has been recently proposed (Telang et al. in IEEE Transactions on Knowledge and Data Engineering (TKDE), 2011). An important component of this framework is a workload consisting of ranking functions, wherein each function represents an individual user's preferences towards the results of a specific query. At the time of answering a query for which no prior ranking function exists, the similarity model is employed, and is expected to ensure a good quality of ranking as long as a ranking function for a very similar user-query pair exists in this workload. In this paper, we address the problem of determining an appropriate set of user-query pairs to form a workload of ranking functions to support user- and query-dependent ranking for Web databases. We propose a novel metric, termed workload goodness, that quantifies the notion of a "good" workload into an absolute value. The process of finding such a workload of optimal goodness is a combinatorially explosive problem; therefore, we propose a heuristic solution, and advance three approaches for determining an acceptable workload, in a static as well as a dynamic environment. We discuss the effectiveness of our proposal analytically as well as experimentally over two Web databases.
Length of time necessary to view a ball while catching it.

College women (N=65) attempted to catch a tennis ball rebounding from a wall to which the ball was projected from a pitching machine. Ss were permitted to see the ball at the end of flight for 0.5, 0.4, 0.3, 0.25, or 0.2 sec. There were significant differences among each of the conditions, with increased viewing time yielding increased catching success. The correlation coefficients between a measure of simple reaction time and catching success during these five conditions ranged from .04 to -.68.
A simple theoretical description of coulomb polarization effects on the coulomb modified scattering length

Abstract A simple formula is derived for the Coulomb modified s-wave scattering length function in the presence of long-range polarization potentials. When applied to a model of low-energy p-d scattering, the formula reproduces behavior previously described by Kvitsinskii and Merkuriev [Sov. J. Nucl. Phys. 41 (1985) 412].
Discrimination and generalization by rats of temporal stimuli lasting for minutes

Abstract In three experiments, rats learned to respond differentially to reinforced and nonreinforced trials when the length of the intertrial interval (ITI) predicted the trial outcome (reinforcement or nonreinforcement). Rats in control groups, for whom the length of the ITI did not predict the outcome, did not show differential performance on nonreinforced and reinforced trials. Generalization gradients obtained following discrimination training were comparable to those obtained following discrimination training with other types of discriminative stimuli. That is, groups which had shown differential performance in discrimination training yielded generalization gradients with fastest speeds at the previously reinforced ITIs, slowest speeds at the previously nonreinforced ITIs, and intermediate speeds at ITIs of intermediate length. Control groups yielded flat gradients across all ITIs tested. These effects were shown for relative time discrimination (short time = reinforcement, long time = nonreinforcement, or the reverse) and also for an absolute time discrimination (long and short time = reinforcement, middle time = nonreinforcement or the reverse). This method was effective for time duration measured in minutes rather than seconds, as is more commonly the case.
A cryogenic optical telescope for inertial pointing in the milli-arc-sec range

We report the test results of the prototype telescope which is part of a system that provides the inertial reference frame for Gravity Probe B. The fused silica star-tracking telescope, which has an effective focal length of 3.8 m at room temperature, experienced a 5 cm focal position shift upon cooling to 4.2 K. A method to compensate this focal shift is described. The photo sensor for the telescope uses Si PIN photodiodes and Si JFET preamplifiers, all mounted on a miniature thermal platform to accommodate the approximately 80 K operating temperature of the JFETs. An electronics noise level of 17 aA(Hz)1/2 at 10 Hz has been achieved. At this noise level, photon noise dominates for 5th magnitude candidate guide stars selected for the mission.
Uncertainties in interpretation of isotope signals for estimation of fine root longevity: theoretical considerations

This paper examines uncertainties in the interpretation of isotope signals when estimating fine root longevity, particularly in forests. The isotope signals are depleted δ13C values from elevated CO2 experiments and enriched Δ14C values from bomb 14C in atmospheric CO2. For the CO2 experiments, I explored the effects of six root mortality patterns (on–off, proportional, constant, normal, left skew, and right skew distributions), five levels of nonstructural carbohydrate (NSC) reserves, and increased root growth on root δ13C values after CO2 fumigation. My analysis indicates that fitting a linear equation to δ13C data provides unbiased estimates of longevity only if root mortality follows an on–off model, without dilution of isotope signals by pretreatment NSC reserves, and under a steady state between growth and death. If root mortality follows the other patterns, the linear extrapolation considerably overestimates root longevity. In contrast, fitting an exponential equation to δ13C data underestimates longevity with all the mortality patterns except the proportional one. With either linear or exponential extrapolation, dilution of isotope signals by pretreatment NSC reserves could result in overestimation of root longevity by several-fold. Root longevity is underestimated if elevated CO2 stimulates fine root growth. For the bomb 14C approach, I examined the effects of four mortality patterns (on–off, proportional, constant, and normal distribution) on root Δ14C values. For a given Δ14C value, the proportional pattern usually provides a shorter estimate of root longevity than the other patterns. Overall, we have to improve our understanding of root growth and mortality patterns and to measure NSC reserves in order to reduce uncertainties in estimated fine root longevity from isotope data.
Optimization of Base Thermal Protection System for Advanced Saturn II Boosters Employing Strap-On Solid-Propellant Motors

Optimization of base thermal protection system for advanced Saturn II boosters employing strap-on solid propellant motors
Possibility of dying as a unified explanation of why we discount the future, get weaker with age, and display risk-aversion.

I formulate a simple and parsimonious evolutionary model that shows that because most species face a possibility of dying because of external factors, called extrinsic mortality in the biology literature, it can simultaneously explain (a) why we discount the future, (b) get weaker with age, and (c) display risk-aversion. The paper suggests that testable restrictions—across species, across time, or across genders—among time preference, aging, and risk-aversion could be analyzed in a simple framework (JEL A10, D90).
Evidence for an RNA-based catalytic mechanism in eukaryotic nuclear ribonuclease P.

Ribonuclease P is the enzyme responsible for removing the 59-leader segment of precursor transfer RNAs in all organisms. All eukaryotic nuclear RNase Ps are ribonucleoproteins in which multiple protein components and a single RNA species are required for activity in vitro as well as in vivo. It is not known, however, which subunits participate directly in phosphodiester-bond hydrolysis. The RNA subunit of nuclear RNase P is evolutionarily related to its catalytically active bacterial counterpart, prompting speculation that in eukaryotes the RNA may be the catalytic component. In the bacterial RNase P reaction, Mg(II) is required to coordinate the nonbridging phosphodiester oxygen(s) of the scissile bond. As a consequence, bacterial RNase P cannot cleave pre-tRNA in which the pro-RP nonbridging oxygen of the scissile bond is replaced by sulfur. In contrast, the RNase P reaction in plant chloroplasts is catalyzed by a protein enzyme whose mechanism does not involve Mg(II) coordinated by the pro-RP oxygen. To determine whether the mechanism of nuclear RNase P resembles more closely an RNA- or a protein-catalyzed reaction, we analyzed the ability of Saccharomyces cerevisiae nuclear RNase P to cleave pre-tRNA containing a sulfur substitution of the pro-RP oxygen at the cleavage site. Sulfur substitution at this position prohibits correct cleavage of pre-tRNA. Cleavage by eukaryotic RNase P thus depends on the presence of a thio-sensitive ligand to the pro-RP oxygen of the scissile bond, and is consistent with a common, RNA-based mechanism for the bacterial and eukaryal enzymes.
Direct and indirect effects of a thrips‐transmitted Tospovirus on the preference and fitness of its vector, Frankliniella fusca

Phytoviruses including tospoviruses are known to affect the behavior and fitness of their vectors both positively and negatively. In this study, we investigated the effects of Tomato spotted wilt virus (TSWV) (family Bunyaviridae, genus Tospovirus) infection on the fitness and feeding ability of tobacco thrips, Frankliniella fusca (Hinds) (Thysanoptera: Thripidae) using peanut, Arachis hypogaea L. (Fabaceae), as a host. Potentially viruliferous F. fusca laid more eggs than non-viruliferous F. fusca. In contrast, fewer potentially viruliferous F. fusca developed into adults and required a longer developmental time than non-viruliferous F. fusca, indicating a direct negative effect of the virus on thrips fitness. In addition, no-choice feeding tests indicated that non-viruliferous F. fusca fed more rapidly than potentially viruliferous F. fusca. Typically, phytovirus infections are known to enhance the availability of vital nutrients such as free amino acids in infected host plants and to affect other important physiological processes negatively. Free amino acids are known to play a vital role in egg production and development. Further investigations in this study revealed that leaflets of infected plants had ca. 15 times more free amino acids than non-infected leaflets. TSWV-infected leaflets were used to rear potentially viruliferous thrips. Higher amino acid levels in TSWV-infected leaflets than in non-infected leaflets could have contributed to increased oviposition by potentially viruliferous F. fusca compared to non-viruliferous F. fusca. Taken together, these results suggest that increased concentrations of free amino acids in TSWV-infected plants might serve as an incentive for thrips feeding on otherwise unsuitable hosts, thereby facilitating TSWV acquisition and transmission.