cssi/SciSciGPT-SciSciNet huggingface dataset:
Amortizing 3D graphics optimization across multiple frames

Abstract : This paper describes a mechanism for improving rendering rates dynamically during runtime in an interactive three-dimensional graphics application. Well-known techniques such as transforming hierarchical geometry into a flat list and removing redundant graphics primitives are often performed off-line on static databases, or continuously every rendering frame. In addition, these optimizations are usually performed over the whole database. We observe that much of the database remains static for a fixed period of time, while other portions are modified continuously (e.g. the camera position), or are repeatedly modified during some finite interval (e.g. during user interaction). We have implemented a runtime optimization mechanism which is sensitive to repeated, local database changes. This mechanism employs timing strategies which optimize only when the cost of optimization will be amortized over a sufficient number of frames. Using this optimization scheme, we observe a rendering speedup of roughly 2.5 in existing applications. We discuss our initial implementation of this mechanism, the improved timing measurements, the issues and assumptions we made, and future improvements.
Oestrogen and inhibition of oxidation of low-density lipoproteins in postmenopausal women

Oxidative modification of low-density lipoprotein (LDL) may be atherogenic. We studied the time of onset of LDL oxidation (lag) in 18 postmenopausal women before and after intraarterial infusion of 17 beta-oestradiol, after 3 weeks' patch administration in 12 of these women, and 1 month after discontinuation in 10. The lag increased from baseline after acute infusion (from 134 [SD41] to 167 [36] min, p = 0.01) and after the patch (132 [31] to 178 [45] min, p = 0.009). After discontinuation of oestradiol, the lag returned to baseline. This study shows an antioxidant effect of physiological levels of 17 beta-oestradiol, which may contribute to an anti-atherogenic action.
Immunity and Intracellular Infection: Resistance to Bacteria in Mice Infected with a Protozoan

Mice infected with the intracellular parasite Toxoplasma gondii for periods of as long as 7 months were resistant to challenge with numbers of Listeria monocytogenes and Salmonella typhimurium that were uniformly lethal to normal mice. This resistance did not appear to depend on the strain of toxoplasma employed or the route of inoculation of either toxoplasma or bacteria. Onset of immunity to listeria was demonstrable as early as 1 to 2 days after infection with toxoplasma. Resistance to toxoplasma was not demonstrable in mice immune to listeria. Interferon did not appear to be a mediator of the immunity observed in toxoplasma-infected mice.
Scotopic spectral sensitivity of phakic and aphakic observers extending into the near ultraviolet

Despite interest in ultraviolet (UV) damage and UV vision in lower vertebrates, there are few recent publications on human UV sensitivity. We obtained dark-adapted spectra from 4 aphakic and 5 normal eyes at 8.8 degrees off-fovea using the staircase method. Our measurements extended from 314.5 nm, near the limit imposed by corneal UV absorbance, to 650 nm. Phakic and aphakic sensitivities resembled the traditional rod spectrum at long wavelengths with a peak around 500 nm. However, aphakic subjects were much more sensitive than phakic observers below 420 nm. From phakic volunteers ranging in age from 22 to 43 we deduced lens absorbance which depressed sensitivity at 350 nm by approx. 4 log units (n = 7 phakic runs on 5 eyes, average age = 30) as expected. We show a maximum lens absorbance at 355-360 nm and a UV window in the lens absorbance at 315 nm consistent with data on optical density of human lenses.
SNAPP: stateless network-authenticated path pinning

This paper examines a new building block for next-generation networks: SNAPP, or Stateless Network-Authenticated Path Pinning. SNAPP-enabled routers securely embed their routing decisions in the packet headers of a stream of traffic, effectively pinning a flow's path between sender and receiver. A sender can use the pinned path (even if routes subsequently change) by including the path embedding in later packet headers. This architectural building block decouples routing from forwarding, which greatly enhances the availability of a path in the face of routing misconfigurations or malicious attacks. To demonstrate the extreme flexibility of SNAPP, we show how it can support a wide range of applications, including sender-controlled paths, expensive route lookups, sender anonymity, and sender accountability. Our analysis shows that SNAPP's overhead is low, and the system is easily implemented in hardware. We believe that SNAPP is a worthy addition to the network architect's toolbox, enabling a variety of new designs and trade-offs.
ABA triblock copolymers with a ring‐opening metathesis polymerization/macromolecular chain‐transfer agent approach

Block copolymers containing polystyrene and polycyclooctene were synthesized with a ring-opening metathesis polymerization/chain-transfer approach. Polystyrene, containing appropriately placed olefins, was prepared by anionic polymerization and served as a macromolecular chain-transfer agent for the ring-opening metathesis polymerization of cyclooctene. These unsaturated polymers were subsequently converted to the corresponding saturated triblock copolymers with a simple heterogeneous catalytic hydrogenation step. The molecular and morphological characterization of the block copolymers was consistent with the absence of significant branching in the central polycyclooctene and polyethylene blocks [high melting temperatures (114-127 °C) and levels of crystallinity (17-42%)]. A dramatic improvement in both the long-range order and the mechanical properties of a microphase-separated, symmetric polystyrene-polycyclooctene-polystyrene block copolymer sample was observed after fractionation.
Seasonal birth patterns in myositis subgroups suggest an etiologic role of early environmental exposures.

Objective To evaluate whether seasonal early environmental exposures might influence later development of autoimmune disease, by assessing distributions of birth dates in groups of patients with idiopathic inflammatory myopathies (IIMs). Methods We assessed birth patterns in groups of patients with juvenile-onset IIM (n = 307) and controls (n = 3,942) who were born between 1970 and 1999, and in groups of patients with adult-onset IIM (n = 668) and controls (n = 6,991) who were born between 1903 and 1982. Birth dates were analyzed as circular data. Seasonal clustering was assessed by the Rayleigh test, and differences between groups by a rank-based uniform scores test. Results The overall birth distributions among patients with juvenile IIM and among patients with adult IIM did not differ significantly from those among juvenile and adult controls, respectively. Some subgroups of patients with juvenile IIM had seasonal birth distributions. Hispanic patients with juvenile-onset IIM had a seasonal birth pattern (mean birth date October 16) significantly different from that of Hispanic controls (P = 0.002), who had a uniform birth distribution, and from that of non-Hispanic patients with juvenile-onset IIM (P < 0.001), who had a mean birth date of May 2. Juvenile dermatomyositis patients with p155 autoantibody had a birth distribution that differed significantly from that of p155 antibody–negative juvenile dermatomyositis patients (P = 0.003). Juvenile IIM patients with the HLA risk factor allele DRB1*0301 had a birth distribution significantly different from those without the allele (P = 0.021). Similar results were observed for juvenile and adult IIM patients with the linked allele DQA1*0501, versus juvenile and adult IIM patients without DQA1*0501, respectively. No significant patterns in birth season were found in other subgroups. Conclusion Birth distributions appear to have stronger seasonality in juvenile than in adult IIM subgroups, suggesting greater influence of perinatal exposures on childhood-onset illness. Seasonal early-life exposures may influence the onset of some autoimmune diseases later in life.
Purification and functional reconstitution of soybean nodulin 26. An aquaporin with water and glycerol transport properties

Infection of soybean roots by nitrogen-fixing Bradyrhizobium japonicum leads to expression of plant nodule-specific genes known as nodulins. Nodulin 26, a member of the major intrinsic protein/aquaporin (AQP) channel family, is a major component of the soybean symbiosome membrane (SM) that encloses the rhizobium bacteroid. To investigate the water and solute transport characteristics of nodulin 26, we purified the protein from SMs and reconstituted it into carboxyfluorescein-loaded liposomes for transport studies using stopped-flow spectrofluorimetry. Liposomes containing nodulin 26 exhibited a high osmotic permeability (Pf = 0. 012 +/- 0.0013 cm/s), a value fivefold higher than that obtained with control liposomes. Water flux through nodulin 26 showed a low activation energy (Ea) (4.07 kcal/mol) and was reduced 70% upon addition of 1 mM HgCl2. Reconstituted nodulin 26 exhibited a single-channel conductance of 3.8 +/- 2.5 x 10(-)15 cm3/s (n = 3), a value that is lower than other characterized AQPs. Nodulin 26 proteoliposomes also facilitate glycerol transport, showing a 43-fold higher rate of glycerol flux than control liposomes. This observation was supported by expression experiments in Xenopus oocytes that showed that nodulin 26 facilitated glycerol flux in a manner indistinguishable from the Escherichia coli GlpF glycerol facilitator. Consistent with the results of water transport, glycerol transport was inhibited by HgCl2 and showed a low Ea (4.43 kcal/mol). These results indicate that nodulin 26 is a multifunctional AQP that confers water and glycerol transport to the SM, and likely plays a role in osmoregulation during legume/rhizobia symbioses.
A Wind Tunnel External Balance Calibration using Design of Experiments

*† A large scale external balance calibration method is described through a case study at the Langley Full-Scale Tunnel. A platform balance was calibrated using a fractional factorial statistically designed experiment. A dead-weight loading scheme was developed for simultaneous application of moments and forces. A runefficient test matrix using 36 points was implemented in a calibration experiment. Physical constraints to load combinations obviated modifications to the standard orthogonal factorial design structure which introduced a degree of multicollinearity in the model coefficients. Careful choice of design points mitigated any problems with correlation. A successful calibration experiment was conducted which included empirical model validation.
Late Wisconsin glacial advance and retreat patterns in southwestern Ohio, USA

Despite the application of radiocarbon dating for more than three decades along the southern margin of the Laurentide Ice Sheet, fundamental questions about the timing of glacial advances remain. For one of its sublobes, the Miami, we undertook areal mapping, detailed lithostratigraphic analysis, and radiocarbon dating to interpret four pulses of ice advance. On top of the undated sediments deposited during the first advance is a major unconformity. The second advance occurred about 20,000 BP and marks the beginning of the late Wisconsin glaciation. A minor recession (more than 30 km) ensued, but plants did not reoccupy the landscape. A third advance of the ice margin produced a stone-rich lodgement till to within 20 km of the late Wisconsin maximum. The final ice motion only occurred in the northern part of the study area and may be of local extent. Large accumulations of supraglacial gravity flowtills and outwash mark the final ice-margin retreat. Of these. only the second advance is well dated. This study implies that the number of advances of the ice margin is fewer than previously suggested. Consequently we argue that several of the sublobes across the southern margin of the Laurentide Ice Sheet acted in unison for the interval of 22.000 to 18.000 BP implying ice-sheet external forcing.
Alternated delta and mu receptor activation: a stratagem for limiting opioid tolerance.

Abstract The development of tolerance to the antinociceptive effects of chronically administered delta (δ) and mu (μ) agonists was examined in vivo in rats using a protocol of alternated preferential activations of δ and μ receptors. This was accomplished by alternated chronic administrations of the relatively δ- and μ-selective agonists DADLE ([ d -Ala 2 , d -Leu 5 ]-enkephalin [15] and morphine sulfate (MSO 4 ) [4], respectively. Specifically, the agonists were given as 3 sequential 6 day cycles: 1. (1) osmotic pump infusions of DADLE into the lumbar intrathecal space; 2. (2) followed by intraperitoneal injections of MSO 4 ; 3. (3) followed again by intrathecal DADLE infusions. Following each cycle, the agonists' antinociceptive activities were measured using the tail-flick test of nociception. These were compared to their baseline (i.e., drug-naive) activities as a measure of tolerances. In a separate experiment the same total intrathecal dose of DADLE was infused chronically over twelve days without an interposed dose of MSO 4 . In the alternated agonist experiment, DADLE's antinociceptive ED 50 value was increased by 10.4-fold, then reverted to only a 1.5-fold change from baseline and was subsequently shifted to a 13.7-fold increase over baseline. After cycle 2 with MSO 4 a significant recovery from DADLE tolerance was noted as compared to that following cycle 1: 1.5- versus 10.4-fold, respectively. Furthermore, the interposition of a cycle of MSO 4 between two cycles of DADLE resulted in a much lesser degree of tolerance for DADLE following cycle 3 (12 days of non-continuous DADLE infusion) than was noted after the 12 day continuous DADLE intrathecal infusion (13.7- versus 25.0-fold tolerance, respectively). DADLE was not restricted to δ receptor-specific activity in this experiment as thoroughly as μ selectivity was achieved with MSO 4 . Because of cross-reactivity to μ receptors, DADLE produced significant cross-tolerance to MSO 4 . The ED 50 value of MSO 4 was shifted to the right from baseline by 5.1-fold after the cycle 1 DADLE infusion. The ED 50 value of MSO 4 was further shifted to the right to 31.6-fold over baseline after cycle 2 with MSO 4 . Despite DADLE's cross-reactivity to μ receptors, the tolerance to MSO 4 regressed from 31.6- to 9.0-fold after the DADLE infusion of cycle 3. This study demonstrated the feasibility of modifying degrees of opioid antinociceptive tolerances in vivo by alternating δ and μ receptor activations.
Angiotensin II signalling events mediated by tyrosine phosphorylation

Angiotensin II is a potent vasoconstrictor that is important in the control of systemic blood pressure. All the hemodynamic effects of angiotensin II result from the AT1 receptor which has the structural features of a seven transmembrane receptor. Both in cultured rat aortic smooth muscle cells and rat glomerular mesangial cells, angiotensin II stimulates the rapid tyrosine phosphorylation of phospholipase C-gamma 1 (PLC-gamma 1). Tyrosine kinase inhibitors that block this phosphorylation also block the angiotensin II-mediated production of 1,4,5 inositol trisphosphate (1,4,5-IP3) and the intracellular release of Ca2+. The cellular tyrosine kinase c-src appears to play a critical role in the angiotensin II-stimulated tyrosine phosphorylation of PLC-gamma 1 and the generation of 1,4,5-IP3. We have also found that angiotensin II stimulates the tyrosine phosphorylation and activation of the JAK family of intracellular kinases. This in turn activates the STAT family of transcription factors. Angiotensin II, working through the AT1 receptor, uses tyrosine phosphorylation as a mechanism to convey signals from the cell surface to the cell nucleus.
Setting your sights on getting engaged

Through a range of evidence-based tools, we work with veterinary practices to identify areas for improvement and growth within their business. Our work isn't focused solely on increasing profit – although in this economic climate it's certainly an important factor – but also on creating strategies which enable a veterinary practice to deliver the best possible service for pet owners and the right environment for the team.
The “New Social Studies”—Retrospect and Prospect

When I look back to the 1960s, I cannot help but feel sentimental about the New Social Studies movement that began very strong and then suddenly disintegrated. Being part of the movement, I am in a...
Accounting for the costs and benefits of human resource development programs: An interdisciplinary approach

Abstract An interdisciplinary approach to measuring the costs and social and financial benefits of human resource development is presented. The approach includes three distinct components: a cost model, an effectiveness model, and a cost-benefit comparison. The diverse interdisciplinary measures of development programs are presented. A critical discussion of the role of human resource accounting and other accounting measures in evaluation is included. Examples from two organizations illustrate the measurement approach. An examination of program evaluation criteria highlights the effect of cost-benefit analyses on the human resource development movement.
Lessons learned from The Skeptical Environmentalist: An environmental health perspective

Few books about the environment have generated as much heated debate as Bjorn Lomborg's 'The Skeptical Environmentalist: Measuring the Real State of the World', published by Cambridge University Press in 2001. A flavor of the controversy can be gleaned from a series of reviews and rebuttals published in 'Scientific American' (Rennie 2002). In general, most positive reviews appeared in the popular press (e.g., 'The Economist', 'Washington Post Book Review', 'The Wall Street Journal') and most negative reviews appeared in the scientific press (e.g., 'Science', 'Nature', 'Bioscience'). Although 'The Skeptical Environmentalist' (TSE) addresses a number of environmental health issues, voices from the environmental health community have not been prominent among the participants in this debate. Now that the dust from the initial stampede to praise and condemn the book has settled, we will explore lessons to be learned from TSE and the associated debate from an environmental health perspective.
Pedal wave recovery following transection of pedal nerves in the slug, Limax maximus

The giant garden slug, Limax maximus, crawls by producing sequential pedal waves that propagate forward along a medial band of muscle running the full length of the foot. Nerves that originate in the pedal ganglion appear to innervate the foot musculature along its length, but not all seem to be essential for the initiation and maintenance of pedal wave activity. When nerves running backward from the pedal ganglion were transected, the portion of the sole posterior to the cut initially showed no pedal waves, and pedal waves anterior to the cut showed reduced wave velocity and frequency. After 3 to 21 days, depending primarily on how anterior the transection, fully-formed pedal waves reappeared in the denervated region of the sole. Waves were propagated along the entire foot, but their velocity and frequency remained lower than found in normal animals or in sham-operated controls. Methylene blue staining, and electrical stimulation and recording failed to reveal evidence of reinnervation in animals that had recovered full-foot pedal wave activity. The results suggest that coordinated pedal waves can be maintained on parts of the sole that lack direct connections with the CNS by spread of excitation through the peripheral plexus of the foot.
An individual-based model of alpine plant distributions

Abstract Our objective was to evaluate the relationships between alpine plant distributions and environmental conditions in order to predict the spatial distribution of major alpine plant communities found along the Front Range of the Rocky Mountains in the western U.S. Our approach was to modify the individual plant-based steppe model to simulate plant responses for three alpine communities found on Niwot Ridge, Colorado, USA: fellfield, dry meadow, and wet meadow. We used the alpine model to evaluate the relationship between alpine plants and their environment both for conditions typical of each community and for conditions along a gradient that includes transitions between communities. We also analyzed model behavior using sensitivity analysis, and tested the ability of the model to simulate alpine plant community dynamics using verification and validation procedures. The individual plant-based alpine model tracks the recruitment, growth, and mortality of individual plants on a small plot (0.09 m 2 ) through time at an annual time step. Eighteen species with the greatest abundance in fellfield, dry meadow, and moist meadow communities, and representing a range of life history characteristics and environmental responses are included. Environmental factors in the model are average daily maximum temperature during the growing season, growing season soil water availability, snow depth, and disturbances. Recruitment and mortality by species have elements of stochasticity whereas growth of an individual plant is determined by resource availability and abundance of plants. Patterns of species composition and aboveground biomass simulated by the model were in general agreement with observations from the three alpine communities. Simulated fellfield communities were dominated by cushion plants, dry meadow communities were dominated by Kobresia myosuroides and Acomastylis rossii , and moist meadow communities were dominated by Acomastylis rossii and Deschampsia caespitosa . Shifts in species composition and dominance were observed along the two environmental gradients investigated (soil water availability and snow depth). Cushion plants dominated areas of low soil water and snow depth representative of fellfield conditions. A shift to graminoid-dominated vegetation, in particular K. myosuroides , occurred over a narrow range of soil water conditions and snow depth. At high soil water and snow depth, this species decreased in biomass as a result of snow-induced mortality, and a forb and graminoid species ( A. rossii and D. caespitosa , respectively) dominated the vegetation. The transition from dry meadow to moist meadow was more gradual than the transition from fellfield to dry meadow. Our results suggest that an individual-based approach is useful in understanding alpine plant community dynamics, and in synthesizing information on processes operating across a range of spatial and temporal scales in alpine communities.
Health Care Needs and Residential Settings: A National Survey and Policy Perspectives.

The relationship between health care needs and residential service placement among older persons with mental retardation is explored. Findings from the 1985–86 Center for Residential and Community Services (CRCS) study of persons over the age of 62 living in residential facilities owned, operated and/or licensed by developmental disabilities agencies are presented. A 10 per cent sample of facilities with one or more persons over the age of 62 was selected, including foster care, group homes, large private facilities (16 or more residents) and state institutions. The final sample consisted of 370 residents in 235 facilities, with an average age of 70 years. Information about the residents was completed by direct careproviders who knew the residents well. For purposes of comparison, findings about persons with mental retardation living in nursing homes and older persons in general living in the community are also presented.The findings highlight the importance of using the older population in general as a r...
Extended Ross procedure for aortic valve stenosis and ascending aortic and arch hypoplasia

A 12-month-old infant underwent extended Ross procedure to repair not only valvar and supravalvar aortic stenosis, but also the entire ascending aorta and transverse arch using the pulmonary autograft.
Newspapers, official advertisements and the intentions of public notice laws

Newspapers as a record of the day's events and conduit for public business have been part of life in the United Stales for several hundred years, many local and state government charters designate a “newspaper of record,” “official newspaper,” or “legal newspaper” specifically for the posting of public notices. Since the primary purpose of the printing of legal notices is to give the widest publicity practicable, statutory law generally considers a newspaper on the basis of general circulation, that is, when it is primarily devoted to news of general interest to the public. New Jersey recently adopted the use of summaries of proposed ordinances and budgets rather than full‐text legal advertisements to meet the intent of public notice on the grounds of economy. This, of course, begs the question of whether or not the intention of public notice has in fact been met by summaries rather than full‐text legal advertisements in official newspapers. The focus of this paper is a review of the reasons for which ful...
The effect of dissolved oxygen on the growth of young-of-the-year winter flounder, Pseudopleuronectes americanus

The effects of constant and diurnally fluctuating levels of dissolved oxygen on the growth of young-of-the-year winter flounder,Pseudopleuronectes americanus, were examined under controlled laboratory conditions. Fish were exposed for either 10 or 11 weeks to constant levels of 6.7 (high) and 2.2 (low) mg l−1, and a diurnal fluctuation, ranging from 2.5 to 6.4 mg 02l−1. Growth rates, calculated for both standard length and weight, for fish exposed to low and diurnally fluctuating levels were significantly reduced (p < 0.001) as compared to those for fish exposed to the high level. Growth rates of fish exposed to the high level were over twice those of fish held under low oxygen conditions. Under fluctuating conditions, fish grew at intermediate rates. Following these exposures, all fish were subsequently held at 7.2 mg Oz l−1 for five weeks. Growth rates increased over two and a half times for fish previously exposed to the low oxygen level and were significantly (p < 0.001) higher than for the other two groups.
Failure to protect ducklings against malaria by vaccination with histidine-rich protein

Abstract Vaccination of white Pekin ducklings, bred either on the east (New York) or the west (California) coast of the USA, with a histidine-rich protein provided no significant protection against subsequent challenge with 2 × 10 7 Plasmodium lophurae per kg body-weight.
Constitutive Equations for the Thermomechanical Response of René 80: Part 2—Effects of Temperature History

The unified constitutive equations for Rene 80 developed by Bhattachar and Stouffer (1992) are used to predict the thermomechanical fatigue (TMF) response of a Nickel base superalloy Rene 80 between 649 C and 1,093 C. Predictions using these equations suggest that temperature history effects are significant during TMF, and that the TMF response of Rene 80 cannot be predicted completely using only isothermal parameters. It is postulated without metallurgical observations that the two deformation mechanisms in Rene 80, planar slip at low temperatures and dislocation climb at high temperatures, produce characteristic microstructures which interact under nonisothermal conditions to produce extra hardening that is not present during isothermal deformation. A state variable approach has been used to model this interaction. The nonisothermal model with temperature history effects could successfully predict the initial and saturated TMF response, and block isothermal response of Rene 80 from several tests between 649 C and 1,093 C.
Further Comments on “Controlling Sex” in Chickens

ABSTRACT A recent report by van Tienhoven (1957) effectively refutes several claims made by Seltzer (1956) in his patent dealing with so-called “sex reversal” in birds. In particular, van Tienhoven showed that Seltzer’s method of dipping eggs in a synthetic estrogen solution, although effective in modifying embryonic sex differentiation, did not produce egg-laying genetic males. Van Tienhoven also showed that the estrogen and androgen treatments used had no significant effects on 9-week body weight of birds hatched from the dipped eggs, an observation of considerable import to those interested in the broiler industry. A less extensive but similar experiment has been conducted by the author, and is reported here because of certain important differences in method and results. Eggs from Delaware pullets mated to New Hampshire cockerels were used so that the genetic sex of each chick could be determined by the down color (silver males and gold females). Since Seltzer’s . . .
Silicon in synthesis: The use of trimethylsilyl cyanide for the synthesis of aliphatic cyanomethylethers

Abstract The conversion of aliphatic alcohols into cyanomethyl ethers via treatment of methyl sulfoxymethyl ethers with trimethylsilyl cyanide - zinc iodide is described.
Virtual private machines: user-centric performance

Inconsistent system behavior causes unpredictable performance which is known to stress users; making the system perform consistently should remove this source of user stress. Operating systems currently provide the illusion that each application runs on a dedicated Virtual Machine. This paper proposes incorporating performance into this abstraction, resulting in a Virtual Private Machine. The VPM abstraction aims to improve user-perceived performance by increasing performance consistency, and it is applicable to any user-visible application, from word processors to web servers. To provide VPMs, per-resource performance models allow resources to be scheduled to meet target response times calculated for each user-visible action.
Hemifacial Spasm: Treatment by Microsurgical Facial Nerve Decompression

The literature on hemifacial spasm and its surgical therapy is reviewed, and the authors' experiences with 20 patients are described. Vascular cross compression of the facial nerve adjacent to the brain stem is seen in 90% of the surgical patients. Mobilizing the offending vessel will cure or signif
Carbonic anhydrase in developing avian heart, blood and chorioallantoic membrane

Abstract 1. 1. Carbonic anhydrase has been detected in cardiac tissue, blood, and chorioallantoic membrane of embryonic and hatching chicks by biochemical assay and autoradiography. 2. 2. Enzyme activity in heart was low (0.14 to 0.29 units/mg protein) during embryonic development and peaked (0.85 units/mg protein) near the time of hatching. The role of carbonic anhydrase in chick heart is postulated to be facilitation of diffusion of metabolic CO2 out of the tissue with consequent prevention of acidosis. 3. 3. Carbonic anhydrase was detectable in blood at around day 10 of embryonic development and increased rapidly from day 14 until hatching, an event which parallels rising plasma pCO2. At hatching, blood levels were about half the adult level of 6.8 units/mg protein. 4. 4. In chorioallantoic membrane, carbonic anhydrase also appeared around the 10th day of development, increasing to 1.1 units/mg protein by day 20. Carbonic anhydrase in this tissue is thought to be associated with respiration and calcium release from the shell. 5. 5. Comparison of the activity profiles suggest different signals for enzyme synthesis in the different tissues.
Electron-capture, electron-loss, and impact-ionization cross sections for 103- to 3400-keV/amu multicharged iron ions colliding with molecular hydrogen

We report cross-section measurements for collisions of multicharged iron ions with a molecular-hydrogen target: (a) electron capture and electron loss of the multicharged ions, and (b) impact ionization of the hydrogen target. Iron ions, Fe/sup +q/, were used with charge states q = 3--13 at 103 keV/amu, q = 9--16 at 294 keV/amu, q = 11--22 at 1160 keV/amu, and q = 20--25 at 3400 keV/amu. We find that an empirically determined expression for the electron-capture cross section, sigma = (1.2 x 10/sup -8/) q/sup 3.15/E(keV/amu)/sup -4.48/ cm/sup 2//molecule, describes all the data at and above 275 keV/amu. These measurements are compared with recent theoretical calculations.
Consistency in Latency Measurements and Interpretation of ABR Tracings

Multichannel ABR recordings for 30 otoneurologic patients were reviewed independently by three audiologists to assess interjudge consistency in determining absolute latencies and overall interpreta...
A bivalent dissectional analysis of the high-affinity interactions between Cdc42 and the Cdc42/Rac interactive binding domains of signaling kinases in Candida albicans

The small GTPase Cdc42, a member of the highly conserved Rho family of intracellular GTPases, communicates with downstream signaling proteins via high-affinity interactions with the consensus Cdc42...
Expression of a Marked H2A Histone Protein in Mammalian Cells

Histone protein sequences are highly conserved. In order to determine whether histones with sequences not found in nature would be tolerated in the chromatin of tissue culture cells, a gene for histone H2A.1a was altered by extending the protein coding region with eight amino acids, including three residues for methionine which are lacking in H2A.1a. Isolated clones of HeLa cells transfected with the gene construct were found to produce a novel protein which was resolved from other histone proteins on AUT-AUC two-dimensional gels. One clone, HeLa-B4, in which the novel protein named H2A.E accounted for about 10% of total H2A protein, was studied further. The linkage of H2A.E mRNA concentrations to the rates of DNA and protein synthesis was found to be the same as that of other replication-linked histone mRNA species. The stability of H2A.E in chromatin as well as the partitioning of nascent H2A.E protein between soluble and nuclear fractions was found to be indistinguishable from that of other histone species. This study shows that histone proteins with sequences other than the conserved sequences found in nature may be utilized in tissue culture cells.
Catalytic properties of Escherichia coli F1-ATPase depleted of endogenous nucleotides

Nucleotide-depleted Escherichia coli F1 was prepared by the procedure of Wise et al. (1983, Biochem. J. 215, 343-350). This enzyme had high rates of steady-state ATPase and GTPase activity. When "unisite" ATP hydrolysis was measured using an F1/ATP concentration ratio of 10, all of the substoichiometric ATP became bound to the high-affinity catalytic site and none became bound to noncatalytic sites. The association rate constant for ATP binding was 7 x 10(5) M-1 s-1 and the KdATP was 7.9 x 10(-10) M, as compared to values of 3.8 x 10(5) M-1 s-1 and 1.9 x 10(-10) M, respectively, in native (i.e., nucleotide-replete) F1. Rate constants for bound ATP hydrolysis, ATP resynthesis, and P(i) release, and the reaction equilibrium constant, were similar in nucleotide-depleted and native F1. Therefore, we conclude that occupancy of the noncatalytic sites is not required for formation of the high-affinity catalytic site of F1 and has no significant effect on unisite catalysis. In further experiments we looked for the occurrence of inhibitory, catalytic-site-bound MgADP in E. coli F1. Such an entity has been reported for chloroplast and mitochondrial F1. However, our experiments gave no indication for inhibitory MgADP in E. coli F1.
Detecting Differential and Correlated Protein Expression in Label-Free Shotgun Proteomics

Recent studies have revealed a relationship between protein abundance and sampling statistics, such as sequence coverage, peptide count, and spectral count, in label-free liquid chromatography-tandem mass spectrometry (LC-MS/MS) shotgun proteomics. The use of sampling statistics offers a promising method of measuring relative protein abundance and detecting differentially expressed or coexpressed proteins. We performed a systematic analysis of various approaches to quantifying differential protein expression in eukaryotic Saccharomyces cerevisiae and prokaryotic Rhodopseudomonas palustris label-free LC-MS/MS data. First, we showed that, among three sampling statistics, the spectral count has the highest technical reproducibility, followed by the less-reproducible peptide count and relatively nonreproducible sequence coverage. Second, we used spectral count statistics to measure differential protein expression in pairwise experiments using five statistical tests: Fisher's exact test, G-test, AC test, t-test, and LPE test. Given the S. cerevisiae data set with spiked proteins as a benchmark and the false positive rate as a metric, our evaluation suggested that the Fisher's exact test, G-test, and AC test can be used when the number of replications is limited (one or two), whereas the t-test is useful with three or more replicates available. Third, we generalized the G-test to increase the sensitivity of detecting differential protein expression under multiple experimental conditions. Out of 1622 identified R. palustris proteins in the LC-MS/MS experiment, the generalized G-test detected 1119 differentially expressed proteins under six growth conditions. Finally, we studied correlated expression of these 1119 proteins by analyzing pairwise expression correlations and by delineating protein clusters according to expression patterns. Through pairwise expression correlation analysis, we demonstrated that proteins co-located in the same operon were much more strongly coexpressed than those from different operons. Combining cluster analysis with existing protein functional annotations, we identified six protein clusters with known biological significance. In summary, the proposed generalized G-test using spectral count sampling statistics is a viable methodology for robust quantification of relative protein abundance and for sensitive detection of biologically significant differential protein expression under multiple experimental conditions in label-free shotgun proteomics.
The Challenge Hypothesis and Seasonal Changes in Aggression and Steroids in Male Northern Fence Lizards (Sceloporus undulatus hyacinthinus)

The challenge hypothesis has been very successful in explaining patterns of testosterone secretion in response to social stimuli in avian species. However, there have been few studies in nonavian vertebrates. We tested the challenge hypothesis in male northern fence lizards (Sceloporus undulatus hyacinthinus). These males are highly territorial and nonparental. Consequently, the challenge hypothesis predicts that plasma testosterone concentrations will be insensitive to aggressive interactions. Testosterone concentrations indeed were not significantly affected by either a short (3–15 min) simulated territorial intrusion (“challenge”) in June or a longer (50–60 min) intrusion in July. Levels of corticosterone were elevated in challenged males in the long, but not the short, intrusion. Challenged males displayed significantly more intense territorial behaviors than did unchallenged control males. The intensity of territorial behavior changed significantly across the active season and was positively related to testosterone concentrations. Thus, while testosterone concentrations do not appear to be involved in rapid changes in aggressive behavior in the fence lizard, they probably are important in larger-scale behavioral changes throughout the season.
The role of prior knowledge and missing information in multiattribute evaluation

Abstract Complete information about the features of people, objects, or issues that are being judged is not always present or available. Our study suggests that often perceivers do not recognize the absence of relevant information in forming attitudinal judgments. Experiment 1 demonstrates that the extremity and degree of confidence in judgment are not always affected by missing information. Experiment 2 demonstrates that the extremity of judgment is not always affected by the amount of information presented. The evaluations of individuals highly knowledgeable about the target object were much more likely to be influenced by omissions and by set size relative to the evaluations of less knowledgeable subjects. These findings suggest that sensitivity to missing information increases with content-specific knowledge.
Isothermal Annealing Effects in Irradiated Copper

Copper wires were bombarded with 12-Mev deuterons at low temperatures. The wires were then allowed to anneal isothermally at successive temperatures from -185\ifmmode^\circ\else\textdegree\fi{}C to +167\ifmmode^\circ\else\textdegree\fi{}C. Recovery of the electrical resistivity increase, produced by the bombardment, was observed at all temperatures. The annealing curves obtained for temperatures between -185\ifmmode^\circ\else\textdegree\fi{}C and -60\ifmmode^\circ\else\textdegree\fi{}C were of such a character that only a number of processes with different activation energies could account for them. One-half of the resistivity increase recovered in this range. The activation energies obtained were observed to be proportional to the absolute temperature. A value of 0.44 ev was found near -100\ifmmode^\circ\else\textdegree\fi{}C. Above -60\ifmmode^\circ\else\textdegree\fi{}C the annealing behaved as though it were a single process with a unique activation energy. This process accounted for 25 percent of the increased resistivity and had an energy of 0.68 ev. At room temperature 25 percent of the increase remained, and further anneals to temperatures as high as 167\ifmmode^\circ\else\textdegree\fi{}C produced only an additional 4 percent recovery.Detailed analysis of the data suggests that the single process occurring above -60\ifmmode^\circ\else\textdegree\fi{}C is the result of the annihilation of interstitial atoms and vacancies that are produced by the irradiation. Slight deviations of the recovery rate from that expected of such a second-order process were observed and could be explained as the effect of elastic strains introduced into the lattice by interstitial atoms. The effect of such lattice strains on the rate of vacancy migration was calculated and found to have sufficient magnitude to explain the data. The results also suggested that the low temperature recovery is due to the correlated annihilation of very close interstitial vacancy pairs, the low activation energies being due to large elastic strains in the immediate vicinity of an interstitial. A further result, which can be derived from the activation energy for self-diffusion in copper, is that the energy of formation of a vacancy is 1.39 ev.
Mevalonate metabolism: Effect of K2Cr2O7, a renal tubular toxin

K2Cr2O7 was given to one member of 10 pairs of rats 2.5 hours before injection of RS-[5-14C]mevalonate. The poisoned rats expired 30.8 ± 3.5% less 14CO2 than their unpoisoned controls in the 2.5 hours after mevalonate injection (p < .001) and incorporated 16.3 ± 7.1% less label into renal (p<.05) and 63.7 ± 12.0% more label into hepatic unsaponifiable lipids (p < .001). K2Cr2O7 had no effect on the oxidation of Na[1-14C]octanoate. These changes occurred at least 14 hours before any previously demonstrated effect of K2Cr2O7 on the kidney and represent an early biochemical expression of renal tubular damage.
MRI for Electrophysiology

Catheter ablation is a first-line treatment for many cardiac arrhythmias and is generally performed under x-ray fluoroscopy guidance. However, current techniques for ablating complex arrhythmias such as atrial fibrillation and ventricular tachycardia are associated with suboptimal success rates and prolonged radiation exposure. Pre-procedure three-dimensional (3-D) MRI has improved understanding of the anatomic basis of complex arrhythmias and is being used for planning and guidance of ablation procedures. A particular strength of MRI compared to other imaging modalities is the ability to visualize ablation lesions. Post-procedure MRI is now being applied to assess ablation lesion location and permanence, with the goal of indentifying factors leading to procedure success and failure. In the future, real-time MRI, together with the ability to image complex 3-D arrhythmogenic anatomy and target additional ablation to regions of incomplete lesion formation, may allow for more successful treatment of even complex arrhythmias without exposure to ionizing radiation.
Studies on the nature of bone carbonate.

Abstract 1. 1. The portion of the carbonate of bone which has recently exchanged with the soluble carbon system during life is the portion most susceptible to physical and chemical loss and exchange. 2. 2. Anatomical location does not seem to be very important in the slow aspects of exchange of bone carbonate in fully grown rats. 3. 3. The fraction of freely exchangeable carbonate is approximately the same in vitro as it has been found to be in vivo. 4. 4. In finely ground rabbit bone, the exchangeable fractions of carbonate and phosphate seem to be approximately the same. It is likely that “preferential solubility” of carbonate is merely the result of “incongruent solubility” and does not necessarily prove bone carbonate to be surface bound.
MgNH4 exchange on humic acid: A radiotracer technique for conditional exchange constants in a seawater medium

A radiotracer technique, employing 27Mg, is used to determine the Mg released by ammonium exchange on undis-solved humic acid in a seawater medium. This new method allows for the measurement of exchangeable Mg on the solid phase surface, which eliminates the problem caused by the high-Mg background in the seawater matrix. The precision calculated from the counting statistics is better than ±2%; the reproducibility among repeated counts ranged from ±1% to ±3%. The higher sensitivity of the method allows for monitoring the MgNH4 exchange at concentrations as low as 30 mM NH4. This is a major improvement relative to the data obtained with the analytical methods used so far, which allow detection of exchangeable Mg only at NH4 concentrations higher than 1 M. The lower experimental concentrations are more in accordance with the natural ammonium levels found in anoxic marine sediments. For the undissolved humic acid used in this experiment, the amount of exchangeable Mg in apparent equilibrium with an ammonium-free seawater matrix was found to be 96.6 ± 0.4 meq/100g. The MgNH4 exchange on humic acid in seawater comes to a steady-state value in < 18 min. The conditional equilibrium constant obtained for this reaction, Kcond = 0.039 ± 0.001 M−1. The technique can be expanded to other geochemical solid phases in seawater and it can be modified to study the behavior of the major cations by using 24Na, 42K and 49Ca.
Evaluation of Several Techniques for the Detection of Secondary Caries Adjacent to Amalgam Restorations

The objective of this study was to determine the ability of several techniques to detect natural secondary caries adjacent to proximal class II amalgam restorations. Two sites were selected and marked on each of 50 human extracted posterior teeth. Three examiners visually characterized each site independently for signs of demineralization (VI), ditching presence (VD), and color change, and utilized light-induced fluorescence (QLF), and infrared laser fluorescence (LF) techniques. The teeth were sectioned through the selected sites, and the severity of each lesion was determined by confocal laser scanning microscopy (CLSM) as the 'gold standard'. Agreement among examiners was assessed using weighted kappa statistics and showed fair to moderate correlation with all techniques. Sensitivity, specificity, positive predictive value (PPV), negative predictive value and accuracy were determined by utilizing three arbitrary CLSM thresholds. Higher sensitivity was indicated by the QLF and LF than by VI. For PPV and accuracy, QLF and LF showed values higher or similar to VI. Low sensitivity was found for VD. The results obtained in this study suggest that LF and QLF may improve the ability to detect early secondary caries around amalgam restorations.