cssi/SciSciGPT-SciSciNet huggingface dataset:
Granulomatous inflammation and nerve necrosis in a case of apparent idiopathic vocal fold paralysis: report of a case.

Objectives: We will present clinical and pathologic findings of the recurrent laryngeal nerve of a 54-year-old man with apparent idiopathic vocal fold paralysis and discuss clinical and scientific implications of these findings. Study Design: Our design is in the format of a case report with emphasis on the clinical, intraoperative, histologic, and neuropathologic findings, followed by a discussion of contemporary theories of idiopathic unilateral vocal fold immobility and the implications of our findings. Methods: A 54-year-old man presented with a 2-year history of unilateral vocal fold motion impairment (VFMI) after an upper respiratory infection. Radiographic and laboratory data revealed no organic cause. The patient clinically appeared to have a classical unilateral vocal fold paralysis and had previously undergone collagen injection and medialization thyroplasty, each with only temporary improvement of voice. We performed ansa cervicalis-recurrent laryngeal nerve anastomosis. Results: Intraoperative dissection revealed an indurated and thickened section of nerve approximately 15 mm in length, located at the beginning of the intralaryngeal segment, near the cricothyroid joint. Segments of this nerve were submitted for histologic evaluation, revealing necrosis with granulomatous inflammation. Postoperative electromyography and videostrobolaryngoscopy were consistent with successful reinnervation from the ansa procedure. Conclusions: The diagnosis of “idiopathic VFMI” likely represents a number of distinct pathologic entities. This case highlights our lack of understanding of idiopathic VFMI and raises many important questions regarding our current theories of this diagnosis. The clinical and pathologic implications are discussed, and continued investigation is recommended.
Vortex simulation of the reacting shear layer - Effects of Reynolds and Damkohler numbers

Numerical nimulat ion is used t o s tudy t h e behavior of an u n s t a b l e , two-dimensional. two3tream. spa t i a l ly -deve lop ing r e a c t i n g s h e a r layer. The cnsteady ma.qn, momentum, energy and s p e c i e s Conservat ion equa t ions a r e In t eg ra t ed by t r a n s p o r t i n g t h e g r a d i e n t s of t h e primary v a r i a b l e s along p a r t i c l e p a t h , while t h e i n t e n P i f i c a t i o n o f t h e s c a l a r g r a d i e n t s due t o t h e s t r a i n f i e l d is incorpoPated u t i l i z i n g t h e r e l a t i o n s h i p between the c o n c e n t r a t i o n F i e l d and t h e d i s t o r t i o n of t h e flow map. A low h e a t r e l e a s e chemical r e a c t i o n is used t o i n v e s t i g a t e t h e e f f e c t s of t u rbu lence on chemistry a t high Reynolds and P e c l e t numbers and moderate Damkohler nLmberP. Resu l t s r evea l a s t r o n g s i m i l a r i t y between t h e d i s t r i b u t i o n s of product c o n c e n t r a t i o n and v o r t i c i t y due t o t h e r e l a t i o n s h i p between p r o d w t g e n e r a t i o n and advec t ion by t h e s t ra in f i e l d a s s o c i a t e d w i t h v o r t i c i t y amalgamation i n t o laPge v o r t e x edd ie s . Ou t s ide t h e l a r g e e d d i e s , t h e .*train f i e l d reduces product c o n c e n t r a t i o n by th inn ing t h e l a y e r and by reducing t h e t ime allowed f o r mixing. A t h igh Reynolds number, t h e r 3 t e of product formation is s t r o n g l y governed by the en t r a inmen t of r e a c t a n t s I n t o t h e l a r g e e d d i e s , which is weakly dependent on Reynolds ntirnber. The e f f e c t of t h e Damkohler number is P t P O n g ar0l;nd D,-1 where the Pate of p m d u c t formation r i s e s rap id ly w i t h t h e $peed of t h e chemical r e a c t i o n , reaching an asymptote around D,-20. The . s t ruc tu re of t h e layer a t high and low DamkohleP numbers 1.analyzed i n d e t a i l . The pQac tan t9 r a t i o aCPOPP t h e l a y e r enhance t h e Pa te of product formation by en fo rc ing s t r o n g e r P o t e n t i a l f o r the chemical r e a c t i o n .
On coupling multi-systems through data sharing

The demand for larger transaction rates and the inability of single-system-based transaction processors to keep up with demand have resulted in the growth of multi-processor-based database systems. The focus here is on coupling in a locally distributed system through multi-system data sharing in which all systems have direct access to the data. This paper addresses the following questions; i) How does a workload running on a single system today perform if migrated to a multi-system? ii) What are the multi-system locking design issues that limit multi-system performance and what is the maximum number of systems that may be effectively coupled? iii) Can alternative locking designs increase the number of systems that may be effectively coupled? Our analysis is based on traces from large mainframe systems running IBM's IMS database management system. We have developed a hierarchical modeling methodology that starts by synthesizing a multi-system IMS lock trace and a reference trace from single-system traces. The multisystem traces are used in trace-driven simulations to predict lock contention and database I/O increase in multi-system environment and to generate workload parameters. These parameters are used in event-driven simulation models to examine the overall performance under different system structures. Performance results are presented for realistic system parameters to determine the performance impact of various design parameters. Lock contention is found to be the critical factor in determining the coupling effectiveness and the effect of alternative locking design to reduce lock contention is studied. The limit on coupling is explored and the analysis indicates that, for this workload, on the order of 6 to 12 systems may be effectively coupled through data sharing, depending on system structure and locking design.
Enhancing Economic Analysis for Fishery Management: Discussion

I have only one comment on the final version of Jon Sutinen's paper. He describes a two-stagedecision process for individual anglers whereby they first decide whether or not to comply and second, if they will not, they then determine the extent of the violation. Actually, it is a simultaneous, not a sequential decision. Individuals determine the net gains from both choices, and then determine whether or not to comply based on the relative net benefits and other cultural and social conventions. However, because the level of utility from either course of action cannot be known unless the level of activity is specified, a decision to comply or not, cannot be made independent of the extent of the potential violation.
Hygroscopic Expansion of some Casting Investments

CREDIT is generally given to Taggart1 for introducing the cast gold inlay to the dental profession. Although he realized that gold shrinks when cooled from molten state to solid state of room temperature, the investment available to him did not supply sufficient compensation. In 1910, Van Horn2 published a paper dealing with a method by which he obtained the compensation by means of wax expansion. The next major research in connection with this problem was the work of Coleman3 at the National Bureau of Standards. He determined the gold shrinkage to be 1.25 per cent and presented a casting technic with compensation values of quantitative nature. The total compensation for the gold shrinkage was obtained by the combination of the setting and thermal expansion of the mold. This procedure is the general practice followed at the present time for compensation. There are some disadvantages to this method. Skinner has indicated the difficulty of obtaining smooth castings and the improper compensation for the casting shrinkage.4 It has been found by Hollenback5 and Scheu6a that castings made at a high temperature are rougher than those made at a low temperature (450° C.), depending upon the great difference in thermal expansion between plaster of Paris and silica, which causes a poor union of the fine particles. This may also result in friability and there may be some warpage due to the differential expansion. A method which provides sufficient compensation at a low mold temperature is the hygroscopic casting technic.b Wilson7 showed that certain plasters expand as much as 0.0044 inch to the inch by taking up moisture from the air. With this information at hand, Scheula, b tested some commercial investment to determine what results the addition of moisture would have. He found6b: (1) All of the casting investments that were tested expanded. (2) The thicker the mix, the greater the expansion. (3) A mix with hot water expanded more than one with cold water. (4) The time at which the mix is placed in the water is of great importance. It was found that if the mix is placed in the water early, it would not expand so much as when placed in a little later. It was also found that if the mix was placed in the water after a certain time, it could not expand to the maximal amount. (5) The temperature of the water in which the mix is placed is important, for two reasons; (a) the temperature of the water controls slightly the expansion of the investment, and (b) water at a temperature of 1000 F. slightly softens the wax pattern so that the fine margins are not marred while expansion is taking place. The mix should remain in the water at least 20 minutes to obtain the full expansion, after which time no further expansion is obtained.
A Heuristic Model of Aerobic Biodegradation of Dissolved Hydrocarbons in Aquifers.

In this paper, we present a heuristic model of mixing and aerobic degradation based on a conceptual understanding of the mixing process in heterogeneous media, rather than on a rigorous derivation from the stochastic transport equations. The mean-behavior, heuristic approach, with a uniform velocity field, was used to reproduce organic plume behavior from a previously published simulation for random pore water velocity fields. The heuristic model presented herein requires that the mixing coefficient be calibrated to explain field data; therefore, in that sense, the model is not predictive. The numerical model uses a modified form of a particle tracking model to account for multispecies transport. Transport simulation includes a random-walk component, while biodegradation is simulated with Monod kinetics. Numerical simulations are presented for nonreactive transport in homogeneous media, and for reactive transport in heterogeneous media. A sensitivity analysis of the model is performed to determine the effect of the mixing coefficient in the model.
Replication-dependent mutagenesis by 5-bromodeoxyuridine: identification of base change and sequence effects on mutability.

The moleeular mechanism of reversion induced by 5-bromodeoxyuridine (BrdU) replication-dependent mutagenesis in mammalian cells was studied. Murine cells with single mutant copies of theE. coli gpt gene integrated chromosomally as part of a shuttle vector were mutagenized with BrdU, and GPT+ revertants were selected. Thirteen mutant cell lines (each of which had agpt gene that varied from the wild-type gene by a different GC → AT base transition in the coding region) were mutagenized, and only four were found to be effectively reverted. All revertantgpt genes that were analyzed had reverted via AT → GC base transition at the original site of mutation, thus demonstrating that replication-dependent mutagenesis by BrdU causes AT → GC transitions. The nine cell lines that were nonrevertible by BrdU replication-dependent mutagenesis could be mutated by this protocol to ouabain resistance as effectively as the four revertible lines, indicating that the nonrevertible lines were susceptible to such mutagenesis. Thus, differences among the cell lines in frequencies of HAT' revertants generated by BrdU replication-dependent mutagenesis could not be attributed to differences in general susceptibility of the lines to the mutagenic protocol. The revertible and nonrevertible lines could not be separated according to the position of the original GC → AT transition in thegpt coding region. However, there was evidence that the DNA base sequence flanking the site of mutation affected the susceptibility of that site to BrdU replication-dependent mutagenesis. For example, six of the cell lines tested hadgpt genes in which the mutant T residue was immediately adjacent on its 3′ side to an A residue, and all six were found to be nonrevertible by BrdU replication-dependent mutagenesis. Furthermore, a target AT base pair flanked by GC base pairs in opposite orientation and either immediately adjacent to or one base removed from the target site on both the 5′ and 3′ sides appeared to have an increased susceptibility to BrdU replication-dependent mutagenesis.
X-RAY POLARIZATION FROM ACCRETING BLACK HOLES: THE THERMAL STATE

We present new calculations of X-ray polarization from black hole (BH) accretion disks in the thermally dominated state, using a Monte Carlo ray-tracing code in full general relativity. In contrast to many previously published studies, our approach allows us to include returning radiation that is deflected by the strong-field gravity of the BH and scatters off of the disk before reaching a distant observer. Although carrying a relatively small fraction of the total observed flux, the scattered radiation tends to be highly polarized and in a direction perpendicular to the direct radiation Agol and Krolik. For moderately large spin parameters (a/M {approx}> 0.9), this scattered returning radiation dominates the polarization signal at energies above the thermal peak, giving a net rotation in the polarization angle of 90 deg. We show how these new features of the polarization spectra from BHs in the thermal state may be developed into a powerful tool for measuring BH spin and probing the gas flow in the innermost disk. In addition to determining the emission profile, polarization observations can be used to constrain other properties of the system such as BH mass, inclination, and distance. New instruments currently under development should be able to exploitmore » this tool in the near future.« less
Intrapopulation variation in reproduction by female eastern kingbirds Tyrannus tyrannus: the impacts of age, individual performance, and breeding site

I used data from a 13-year study of eastern kingbirds Tyrannus tyrannus from central New York, USA, to evaluate the relative impact of female age and body size on reproduction. I also calculated repeatabilities of reproductive traits for both females and the sites where they bred in an attempt to evaluate the relative contribution of each to intrapopulation variation in reproduction. Female age had a strong influence on timing of breeding (breeding date advanced by one day for each year of life), but was not a significant source of variation for clutch size, egg mass, number of young to hatch or fledge, or total seasonal production. Repeatabilities of breeding date for females and sites were both significant (0.284 and 0.181, respectively), but the only other significant repeatabilities were for female clutch size (0.282) and female egg mass (0.746). Among-year repeatabilities of breeding date for females who bred at two or more sites over their lifetime were as high as those for females that were site faithful. Thus, breeding date was probably affected independently by the female and site. No measure of productivity exhibited a repeatable pattern in comparisons made among females or sites. All reproductive traits were entered as dependent variables in a series of stepwise multiple regression analyses in an attempt to identify female properties (size, lifespan and condition) that might be linked proximately to differences in breeding statistics. I found that (a) large birds tended to breed the earliest, (b) clutch size was independent of female size, condition and lifespan, (c) female body size and egg size were correlated positively, but (d) production of young was independent of all measured female properties. Reproduction appears to be linked more closely to the female than to the site. Body size accounts for a portion of the repeatable portion of breeding date and egg mass, but most of the intrapopulation variation in these and other traits remained unexplained.
Diagnostic challenges of using CSF assay of tau and beta-amyloid42 in atypical degenerative dementias of the Alzheimer type

This report presents three cases of atypical degenerative dementias in order to illustrate challenges associated with the use of biologic markers of Alzheimer's disease (AD) for diagnosis and management. Clinical diagnostic methods followed the NINCDS-ADRDA criteria for AD. Additional diagnostic studies included serial neurocognitive testing, MRI, neuroSPECT, ApoE genotyping, and a CSF assay of tau and beta-amyloid(42). For patient 1, both the clinical and biologic markers were consistent with AD. The patient was diagnosed with AD with a high degree of confidence, even though the base rate of nonfamilial AD at this age group (<55 years) is exceedingly rare. This case argues favorably for the use of biologic markers to aid in confirming a diagnosis in an atypical dementia. Patient 2 met the NINCDS-ADRDA criteria for AD, although with less confidence. Neurocognitive data indicated a progressive right hemispheric syndrome, insight was preserved, and ApoE was 3/3, but tau concentrations and beta-amyloid(42) were highly consistent with cut-offs for AD; the differential fell on the Pick's disease/frontotemporal degeneration spectrum. Patient 3 had no clinical evidence of the disease, even when evaluated via extensive neurocognitive testing over a 2-year interval. However, ApoE was 4/4, and CSF assay of tau and beta-amyloid(42) were within the AD range. Therefore, while the CSF assay of tau and beta-amyloid(42) markers was confirmatory of AD, each case was highly atypical. Results illustrate the lack of normative data available when using biologic markers for highly atypical cases, calling into question their usefulness for such patients. These cases illustrate the interplay between neuropsychological and biological markers in establishing neurodegenerative diagnoses.
Herpes simplex virus type I disrupts the ATR-dependent DNA-damage response during lytic infection

Like other DNA viruses, herpes simplex virus type 1 (HSV-1) interacts with components of the cellular response to DNA damage. For example, HSV-1 sequesters endogenous, uninduced, hyperphosphorylated RPA (replication protein A) away from viral replication compartments. RPA is a ssDNA-binding protein that signals genotoxic stress through the ATR (ataxia telangiectasia-mutated and Rad3-related) pathway. The sequestration of endogenous hyperphosphorylated RPA away from replicating viral DNA suggests that HSV-1 prevents the normal ATR-signaling response. In this study we examine the spatial distribution of endogenous hyperphosphorylated RPA with respect to ATR, its recruitment factor, ATRIP, and the cellular dsDNA break marker, γH2AX, during HSV-1 infection. The accumulation of these repair factors at DNA lesions has previously been identified as an early event in signaling genotoxic stress. We show that HSV-1 infection disrupts the ATR pathway by a mechanism that prevents the recruitment of repair factors, spatially uncouples ATRIP from ATR and sequesters ATRIP and endogenous hyperphosphorylated RPA within virus-induced nuclear domains containing molecular chaperones and components of the ubiquitin proteasome. The HSV-1 immediate early protein ICP0 is sufficient to induce the redistribution of ATRIP. This is the first report that a virus can disrupt the usually tight colocalization of ATR and ATRIP.
Cervical Crossing Laminar Screws: Early Clinical Results and Complications

Objective C2 crossing laminar screws are a new technique for axis fixation with a purported lower risk for neurological or vascular injury. However, to date, few clinical series on this technique have appeared in the peer-reviewed literature. This report describes our initial clinical experience and complications using this new spinal fixation technique. Methods Thirty patients underwent high cervical intralaminar fixation with crossing intralaminar screws. Indications for surgery included occiput to cervical fixation for basilar invagination in six patients, fixation for atlantoaxial subluxation or trauma in six patients, cervical swan neck deformity in four patients, and laminectomy and instrumented fusion for cervical stenosis in 14 patients. Two cases involved C3 fixation resulting from congenital anomalies. A total of 59 screws were placed, and the patients were assessed both clinically and radiographically with postoperative computed tomographic scans. Results There were no intraoperative complications and no cases of neurological worsening or vascular injury from hardware placement. One patient reported local neck pain resulting from hardware prominence. Computed tomographic scans demonstrated a partial dorsal laminar breach in 11 patients and violation of the spinal canal in one patient. None of these resulted in neurological symptoms. Early hardware fractures were observed in two patients. Conclusion Crossing C2 laminar screws provide the surgeon with an expanded armamentarium for fixation in the high cervical spine. This technique is straightforward and easily adopted. However, the unique position of the screw heads may result in increased stress and strain on the intralaminar screws. Thus, larger diameter screws or additional fixation points at adjacent levels are recommended.
Prevalence of pulmonary hypertension in end-stage cystic fibrosis and correlation with survival

Background Limited information is available about the prevalence of pulmonary hypertension diagnosed by right heart catheterization (RHC) in patients with cystic fibrosis being evaluated for lung transplantation. It is unclear whether there are factors that can predict the presence of pulmonary hypertension and whether the presence of pulmonary hypertension influences patient outcomes. Methods The study included 57 unique and consecutive adult patients (33 women) with cystic fibrosis who underwent lung transplant evaluation at the University of Florida. Results The average age at evaluation was 31.8 ± 10 years. All patients were in New York Heart Association class III. The median (interquartile range) of mean pulmonary artery pressure (PAP) was 26 (24–30) mm Hg. Thirty-six patients (63.2%) had pulmonary hypertension (mean PAP ≥ 25 mm Hg) and had a significantly higher degree of hypoxemia and oxygen requirements. Echocardiography evidenced limitations for the diagnosis of pulmonary hypertension. The 5-year mortality rate was similar in patients with or without pulmonary hypertension; however, it was higher in 7 patients identified by cluster analysis and in patients with a left ventricular ejection fraction Conclusions More than half of our patients with cystic fibrosis and advanced lung disease have elevation of PAP, usually of mild degree. A lower left ventricular ejection fraction, but not the presence of pulmonary hypertension, was associated with worse outcomes.
Ten tips for terrific videotapes

Video projects can be used to motivate students, integrate curricular objectives, and foster cooperative learning and creativity through technology. Using some or all of the above tips can add zest to a single camera production while providing for instructional activities across the curriculum. Today, the Student Media Festival. Tomorrow, the Emmy!
The pattern of thoroughbred growth is affected by a foal's birthdate

Abstract Understanding equine growth patterns is important when balancing the economic and perceived athletic benefits of large size and rapid growth against the potential associated risk of skeletal abnormalities. Existing Thoroughbred growth data indicate that the long and short term patterns of growth are different based on when a foal is born, however this difference has not previously been quantified for body weight (BW) and withers height (WH). Therefore, the objectives of this study were to (1) accurately and precisely characterize the short term patterns of equine growth separated from the long term sigmoidal pattern and (2) investigate the influence of the day of year on which the foal was born (DOB), age, and day of year (DOY) on the short term pattern of growth. Data for this study consisted of 35,044 BW measurements and 25,987 WH measurements from 2184 horses. Data were collected from 1977 to 2007 on farms located in the United Kingdom, Ireland and the United States. The BW and WH data were examined as changes over age or the DOY on which the measurements were taken. The data were further categorized based on DOB. The Richards sigmoid growth model was fit to the data and percentiles for BW and WH over age described. The long term pattern of growth was similar to that in previous studies of Thoroughbreds. The DOB influenced the short term patterns of BW and WH growth over time, such that at specific ages or on particular DOY foals born in the first 60 days of the year will be growing differently than those born between DOY 91 to 150. The data further indicate that early growth is more closely associated with age, while later growth may be more affected by environment. This study adds to the rich database of Thoroughbred growth data already available and adds significant detail regarding WH development and specific characteristics of short term growth. The data and results presented here should be useful to those managing growing stock and interested in more precisely moderating the pattern of growth. The study also raises questions regarding how the patterns of growth can be controlled and whether certain patterns may be more beneficial or detrimental than others regarding the future health and performance of the horse.
A novel meso-scale combustion system for operation with liquid fuels

Abstract A novel meso-scale combustion concept utilizing a flow-blurring injector to produce fine fuel droplets, a counter-flow heat exchanger to preheat reactants using product gas enthalpy, and porous inert medium to homogenize reactants and stabilize the flame is presented. The overall system is 30 mm long and 17 mm in diameter, with combustor diameter of 10 mm. For atmospheric pressure operation on kerosene fuel, the combustion system achieved heat release rate of up to 460 W, pertaining to energy density of 90 MW/m 3 based on the total volume and 230 MW/m 3 based on the combustor volume. The combustor performance was determined from surface temperatures measured by an infra-red camera, product gas temperature measured by an R-type thermocouple probe, and carbon monoxide (CO) and nitric oxide (NO x ) concentrations measured by a miniature sampling probe attached to gas analyzers. A comprehensive Computational Fluid Dynamics (CFD) model incorporating conjugate heat transfer, radiation heat exchange, flow and heat transfer in PIM, and heat release by combustion was developed and validated in this study. The CFD model accurately predicted the thermal performance of the combustion system. A 1D, burner-stabilized flame model incorporating detailed chemical kinetics was used to predict the flame structure. Model predictions are compared with measured CO and NO x concentrations, and subsequently, analyzed to identify the key reactions affecting the NO x production.
The hydrodynamic function of shark skin and two biomimetic applications

SUMMARY It has long been suspected that the denticles on shark skin reduce hydrodynamic drag during locomotion, and a number of man-made materials have been produced that purport to use shark-skin-like surface roughness to reduce drag during swimming. But no studies to date have tested these claims of drag reduction under dynamic and controlled conditions in which the swimming speed and hydrodynamics of shark skin and skin-like materials can be quantitatively compared with those of controls lacking surface ornamentation or with surfaces in different orientations. We use a flapping foil robotic device that allows accurate determination of the self-propelled swimming (SPS) speed of both rigid and flexible membrane-like foils made of shark skin and two biomimetic models of shark skin to measure locomotor performance. We studied the SPS speed of real shark skin, a silicone riblet material with evenly spaced ridges and a Speedo® ‘shark skin-like’ swimsuit fabric attached to rigid flat-plate foils and when made into flexible membrane-like foils. We found no consistent increase in swimming speed with Speedo® fabric, a 7.2% increase with riblet material, whereas shark skin membranes (but not rigid shark skin plates) showed a mean 12.3% increase in swimming speed compared with the same skin foils after removing the denticles. Deformation of the shark skin membrane is thus crucial to the drag-reducing effect of surface denticles. Digital particle image velocimetry (DPIV) of the flow field surrounding moving shark skin foils shows that skin denticles promote enhanced leading-edge suction, which might have contributed to the observed increase in swimming speed. Shark skin denticles might thus enhance thrust, as well as reduce drag.
CHEMICAL EVENTS ON THE PRIMITIVE EARTH

In this paper the nature of the primitive atmosphere and ocean is considered in the light of geologic and geophysical information. The hypothesis of an early methane-ammonia atmosphere is found to be without solid foundation and indeed is contraindicated. Geologists favor an alternative view-that genesis of air and oceans is a result of planetary outgassing. Some consequences of this view are examined. Volatiles from outgassing interacted with the alkaline crust to form an ocean having a pH 8-9 and tzo produce an atmosphere consisting of CO, C02, N2, and H2. Radiation interacting with such a mixture yields HCN as a principal product. Ultraviolet irradiation of HCN solutions at pH 8-9 yields amino acids and other important substances of biologic interest. The nature of the earth's environment limited the kinds of compounds that might have accumulated in a soup. Arguments concerning feasible components support the view that amino acids and proteins preceded sugars and nucleic acids. If the methane-ammonia hypothesis were correct, there should be geochemical evidence supporting it. What is the evidence for a primitive methane-ammonia atmosphere on earth? The answer is that there is no evidence for it, but much against it. The methane-ammonia hypothesis is in major trouble with respect to the ammonia component, for ammonia on the primitive earth would have quickly disappeared. The effective threshold for degradation by ultraviolet radiation is 2,250 A. A quantity of ammonia equivalent to present atmospheric nitrogen would be destroyed in -30,000 years. Small amounts of ammonia would be reformed, but this process is unimportant in comparison to the destruction. If large amounts of methane had ever been present in the earth's atmosphere, geologic evidence for it should also be available. Laboratory experiments show that one consequence of irradiating a dense, highly reducing atmosphere is the production of hydrophobic organic molecules which are adsorbed by sedimenting clays. The earliest rocks should contain an unusually large proportion of carbon or organic chemicals. This is not the case. The composition of the present atmosphere with respect to the gases neon, argon, krypton, and xenon is crucial. Neon is present on earth to an extent about 10-1O
Three-Dimensional Transport of the Ertel Potential Vorticity and N2O in the GFDL SKYHI Model

Abstract In this study the author investigates the 3D evolution of the Ertel potential vorticity (PV) and N2O in Northern Hemisphere winter from 1 to 10 February of model year 1984 in the GFDL SKYHI model. The diagnosis was done on three isentropic surfaces—800, 450, and 320 K—by using output from the GFDL SKYHI model, which has 1.2° × 1° horizontal resolution, 40 layers in vertical, and 60-s time resolution. The data output was taken twice daily. The high resolution Lagrangian Field Advection Model (FAM), which has no diabatic heating and diffusion, is used to study the evolution of these two fields. The 1° × 1° resolution in FAM gives reasonable results. The following results are found. 1) In the stratosphere there are two kinds of barriers, that is, subtropical barrier and polar barrier for both PV and N2O. The existence of the subtropical barrier is coincident with the subtropical jet. The subtropical barrier is more permeable than the polar barrier. Even though the tropopause acts like a barrier, the...
STI571 sensitizes breast cancer cells to 5-fluorouracil, cisplatin and camptothecin in a cell type-specific manner

Abstract Previously, we demonstrated that Abl kinases are highly active in invasive breast cancer cell lines, and contribute to survival in response to nutrient deprivation, invasion and proliferation. To determine whether an Abl kinase inhibitor, STI571 (Gleevec; imatinib mesylate) sensitizes breast cancer cells to chemotherapeutic agents, we treated three breast cancer cell lines (BT-549, MDA-MB-231, and MDA-MB-468) that have active Abl kinases, with STI571 in combination with several conventional chemotherapeutic drugs frequently used to treat breast cancer, and assessed the effect on cell viability, proliferation, and apoptosis. We found that STI571 had synergistic effects with cisplatin in BT-549 and to some extent in MDA-MB-468 cells; synergized with camptothecin using an alternate dosing regimen in MDA-MB-231 cells; and STI571 synergistically sensitized MDA-MB-468 cells to paclitaxel and to high doses of 5-fluorouracil. Significantly, STI571 increased the ability of cisplatin to inhibit constitutive activation of PI3K/Akt in BT-549 cells, synergized with camptothecin to increase the stability of IκB in MDA-MB-231 cells, and in MDA-MB-468 cells, camptothecin and 5-fluorouracil inhibited STI571-dependent activation of STAT3. In other cell line/drug combinations, STI571 had additive or antagonistic effects, indicating that the ability of STI571 to sensitize breast cancer cells to chemotherapeutic agents is cell type-dependent. Significantly, unlike cisplatin, paclitaxel, and camptothecin, mechloroethamine was strongly antagonistic to STI571, and the effect was not cell line-dependent. Taken together, these data indicate that the cellular milieu governs the response of breast cancer cells to STI571/chemotherapeutic combination regimens, which suggests that treatment with these combinations requires individualization.
System analysis techniques applied to the forrester world model—part I: Sensitivity analysis

Abstract System analysis techniques can be used to study models such as the nonlinear dynamic feedback World Dynamics Model developed by Jay W. Forrester. Through application of sensitivity analysis it was discovered that the capital-investment parameters of the Forrester model exert the greatest influence on model behavior. Due to high sensitivity of these variables, careful inspection of their function and continual updating of their interrelations with other parameters must be performed to insure model accuracy. In many cases perturbation of a multiplier produces the same relative effect as an equal percentage change in one of the parameters designed as control variables. A change in the relation of the multiplier and its dependent variable offers an alternative to the direct control policies suggested by Forrester.
High-dose cyclophosphamide in refractory myasthenia gravis with MuSK antibodies

We describe a 48-year-old woman with seronegative myasthenia gravis (MG) and high-titer of anti-MuSK antibody. She had severe bulbar and respiratory weakness with minimal limb weakness for 2 years. Her disease responded poorly to all the conventional immunosuppressive regimens. Treatment with immunoablative dose of cyclophosphamide led to dramatic and sustained remission of her symptoms. High-dose cyclophosphamide is an effective alternative in patients with unusually refractory disease.
Correlation of magnetic resonance spectroscopic imaging and intracranial EEG localization of seizures. 7

Two and a half million people in US have epilepsy 600,000 individuals have medically intractable epilepsy. Epilepsy surgery offers an alternative treatment and a potential cure. In certain patients, particularly subjects with normal anatomical MRI, evaluation often includes intracranial electrode recording. Continuous monitoring of electrical signals directly from the brain for periods of 1 to 14 days are performed to record actual seizures that provide more precise localization of seizures. Magnetic resonance spectroscopic imaging (MRSI) offers the potential to localize such regions non-invasively. In this study we present results from a comparison of such abnormal region identification for ten patients from both intracranial electrodes and MRSI. The analysis employed both rigid and non-rigid registration methods, as well as localization of intracranial electrodes from CT images. We found that IcEEG and MRSI localization methods were concordant in all ten subjects.
The Nucleus of Comet Hale-Bopp (C/1995 O1): Size and Activity

A review of our current understanding of Comet Hale—Bopp’s nuclear size is presented. Currently the best constraints on the effective radius are derived from late-1996 mid-IR data and near-perihelion radio data. Unfortunately the two regimes give differing answers for the radius. A possible reconciliation of the two datasets is presented that would place the radius at around 30 km. This is a large cometary radius compared to the others that are known, and this motivates a discussion of what makes a large comet different. From several possible large-comet properties, Hale—Bopp’s activity is analyzed, focusing on the production rates, coma jet features, dust optical depth, and relationship with the interplanetary dust environment. The optical depth is particularly important since an optically-thick inner coma could complicate attempted measurements of the “nucleus”.
Infants' Differential Processing of Female and Male Faces

Infants show an interesting asymmetry in face processing:Theyaremorefluentinprocessingfemalefaces thantheyareatprocessingmalefaces.Wehypothesizethat such processing asymmetry results from greater experi- ence with female faces than with male faces early in de- velopment. Asymmetrical face processing may have long- lasting implications for development of face recognition, development of knowledge structures regarding females and males, and social-information processing. We en- courage researchers to use both female and male faces in their face-perception research and to conduct separate analyses for female and male faces.
A Computerized Screening System for Correctional Classification

A new multi-method, computerized screening system for classifying and assigning all felons entering Kentucky's correctional institutions was developed and implemented. This system—consisting of psychological tests, self-report inventories, rating scales, and detailed observations—requires approximately two hours for administration. A detailed, case-history summary covering nine major classification categories and supplying information about the felon's background, interests, abilities, strengths, and weaknesses in 27 criminological, demographical, sociological, and psychological areas of correctional concern is provided. This new system appears both reliable and valid and should prove useful both for initial classification and assignment, and for reclassification and parole review.
Evolution of the Laminar Wake behind a Flat Plate and Its Upstream Influence

Analysis of laminar, two-dimensional, viscous flow of an incompressible fluid over the trailing edge of a vanishingly thin flat plate is presented. A coordinate transformation is introduced which admits sufficient scaling of the problem to enable detailed study of the separating flow and its interactions with the inviscid stream, as well as with a presumed boundary-layer flow in an intermediate region. Second-order boundary-layer theory is applied in an iterative manner to extract a first approximation to the displacement thickness and associated induced pressure distribution. It is found that the near-wake region is nonisobaric, the classical isobaric result of Blasius-Goldstein for displacement thickness being slightly high just prior to the trailing edge and about 10% low downstream. Local corrections to the velocity and pressure distributions are obtained by numerically solving the full Navier-Stokes equations, using the second-order boundary-layer results to establish Dirichlet boundary conditions over a rectangular region enclosing the trailing edge point. It is found that the physical extent of this region is of order R~3/4. Within the region, shear at the plate increases with x and becomes very large at the trailing edge. No significant correction to the displacement thickness was found on resolving the second-order boundary-layer problem, using the Navier-Stokes results as inner boundary conditions.
Surface topography evolution and fatigue fracture in polysilicon MEMS structures

This paper presents the results of an experimental study of the micromechanisms of surface topography evolution and fatigue fracture in polysilicon MEMS structures. The initial stages of fatigue are shown to be associated with stress-assisted surface topography evolution and the thickening of SiO/sub 2/ layers that form on the unpassivated polysilicon surfaces and crack/notch faces. The differences in surface topography and oxide thickness are characterized as functions of fatigue cycling before discussing the micromechanisms of fatigue fracture.
LIAPUNOV FUNCTIONALS AND PERIODICITY IN A SYSTEM OF NONLINEAR INTEGRAL EQUATIONS

In this paper, we construct a Liapunov functional for a system of nonlinear integral equations. From that Liapunov functional we are able to establish the existence of periodic solutions to the system by applying some well-known fixed point theorems for the sum of a nonlinear contraction mapping and compact operator.
Ab initio theory of polar semiconductor surfaces. I. Methodology and the (22) reconstructions of GaAs(111).

A methodology is developed for the theoretical study of the polar surfaces of compound semiconductors. It is based on the calculation of the total energy in the context of density-functional theory in the pseudopotential approximation. The method is used to investigate the (2\ifmmode\times\else\texttimes\fi{}2) reconstructions of GaAs(111). Emphasis is given to the relative chemical potential, which plays a crucial role in determining the lowest-energy geometry for surfaces with different stoichiometries. The total-energy versus chemical-potential curves indicate that there are at least two stable reconstructions. We predict one to be an As-triangle geometry and the other the Ga vacancy.
Selection and Use of Polymer-Based Materials in the Repair of Concrete Structures

A large number of specialty repair concrete products are currently marketed and new products are being continually introduced leaving clients, engineers, and designers bewildered. The paucity of information on the mechanical and thermal properties of a given product complicates material selection. These difficulties force designers to adopt materials that have properties close to those of the original concrete. In so doing they often reject advantages offered by polymer-based products now on the market. The challenge is to understand the properties of each material and select the appropriate one. To assure predictable performance, the designer must have a good knowledge and understanding of the properties of the repair material, how it will interact with the environment in service, and a clear description of maintenance procedures and intervals. Typical properties of currently used polymeric materials in relation to the important aspect of selection based on compatibility with in-service conditions and suitability with the application procedures of the job are discussed.
Begin of the Search for the Quark-Gluon Plasma

LBL has been the cradle where relativistic heavy ion physics began, and where the Hagedorn Statistical Model was first connected to relativistic heavy ion physics. The early program of research at the Bevalac and its development into an international program at CERN, paying tribute to the seminal effort by Howel Pugh, is described.
A transmembrane segment determines the steady-state localization of an ion-transporting adenosine triphosphatase.

The H,K-adenosine triphosphatase (ATPase) of gastric parietal cells is targeted to a regulated membrane compartment that fuses with the apical plasma membrane in response to secretagogue stimulation. Previous work has demonstrated that the α subunit of the H,K-ATPase encodes localization information responsible for this pump's apical distribution, whereas the β subunit carries the signal responsible for the cessation of acid secretion through the retrieval of the pump from the surface to the regulated intracellular compartment. By analyzing the sorting behaviors of a number of chimeric pumps composed of complementary portions of the H,K-ATPase α subunit and the highly homologous Na,K-ATPase α subunit, we have identified a portion of the gastric H,K-ATPase, which is sufficient to redirect the normally basolateral Na,K-ATPase to the apical surface in transfected epithelial cells. This motif resides within the fourth of the H,K-ATPase α subunit's ten predicted transmembrane domains. Although interactions with glycosphingolipid-rich membrane domains have been proposed to play an important role in the targeting of several apical membrane proteins, the apically located chimeras are not found in detergent-insoluble complexes, which are typically enriched in glycosphingolipids. Furthermore, a chimera incorporating the Na,K-ATPase α subunit fourth transmembrane domain is apically targeted when both of its flanking sequences derive from H,K-ATPase sequence. These results provide the identification of a defined apical localization signal in a polytopic membrane transport protein, and suggest that this signal functions through conformational interactions between the fourth transmembrane spanning segment and its surrounding sequence domains.
Economic Forms in Pre-Colonial Ghana

This paper uses a simple physiocratic model to examine forms of economic organization prevailing in Ghana before it was incorporated into the British Empire at the end of the nineteenth century. It is divided into three parts. The first analyzes the village subsistence economy and suggests that the egalitarian nature of the land-tenure system prevented the emergence of a land-owning class and the appropriation of an economic surplus. This led to an economic structure characterized by a low level of material production and a low degree of specialization and exchange. The second part analyzes forms of economic organization associated with long distance trade: that is, the very old northern trade with other parts of Africa, and the southern coastal trade with Europe which began in the fifteenth century. It argues that foreign trade not only expanded the consumption possibilities of the society, as predicted by the theory of international trade, but also introduced a new class structure and greater income inequality, since it allowed a small group to appropriate a surplus for its own use. The third part discusses the relevance of Pre-Colonial forms to twentieth century economic development.