cssi/SciSciGPT-SciSciNet huggingface dataset:
The earth resources technology satellite - Photographic facility quality control program

A detailed description is given of the quality control program used in the photographic laboratory of the NASA-ERTS Ground Data Handling System. The product response variables measured include tone reproduction, resolution, and low spatial frequency noise. In addition to product response variables, certain performance parameters of the laboratory printers and processors are frequently measured in order to produce consistent duplications of archival photography. A description is given of the operation and use of a densitometer/computer interface which is used to calculate three tone reproduction response variables - film speed, average gradient, and base plus fog density. This procedure eliminates the need for any hand plotting of D log E curves to manually determine response variables.
Spectral fluctuations and time-reversal invariance

The effects of time-reversal non-invariance on spectral fluctuations of chaotic systems are considered, and a bound on noninvariance in the nucleon-nucleon interaction is deduced.
Molecular cloning of 3-phenylcatechol dioxygenase involved in the catabolic pathway of chlorinated biphenyl from Pseudomonas putida and its expression in Escherichia coli.

Abstract Genes encoding 3-phenylcatechol dioxygenases were cloned from the chlorobiphenyl-degrading Pseudomonas putida strain OU83, using broad-host-range cosmid vector pCP13. Restriction enzyme analysis of DNA from 2,3-dioxygenase-positive chimeric cosmids showed DNA inserts ranging in size from 6.0 to 30 kilobases. The origin of the DNA insert in hybrid clones was established by using 32P-labeled hybrid clones (pOH101 and pOH810). A 2.3-kilobase HindIII fragment was common to two clones. The 2,3-dioxygenase from the parent P. putida strain, OU83, and the recombinant clones (pOH101 and pOH8101) showed similar characteristics as determined by isoelectric focusing and polyacrylamide gel electrophoresis. The 2,3-dioxygenase from the Escherichia coli recombinant cosmid showed a pI of 5.0, a Km of 14 microM, and broad substrate activity with catechol, 4-chlorocatechol, 4-methylcatechol, and 2,3-dihydroxybiphenyl.
Approximate synthesis of weighted l/sub /spl infin//-optimal compensators

The problem is to find linear time invariant compensators which minimize an incremental weighted norm of the closed-loop system, and it is equivalent to a minimum distance problem in l/sub 1/. The main results establish that, under mild conditions, a minimizer for the problem exists. The author also gives a method for computing an infimizing sequence of suboptimal solutions based on FIR approximation, and a method for computing a converging lower bound on the infimal norm. All required computations are equivalent to finite linear programs. >
An Analysis of the Elements of an All Sky Survey

One component of the NASA search for microwave signals of extraterrestrial intelligent origin will be an all sky survey at a significantly low limiting flux over a broad frequency range. We are currently designing an overall strategy which will permit this survey to be: (1) carried out using existing antennas in less than 3 years of observation time, (2) uniform in sensitivity (within 0.5 db) over the celestial sphere for any given frequency, and (3) complete to 6×10-23 W/m2 or better over the frequency range 1.2GHz≤;ν≤10GHz with a frequency resolution of 32 Hz.
Protein quality and micronutrient availability of extruded corn, soy, sorghum, and cowpea fortified-blended foods

Corn and soybean micronutrient fortified-blended foods (FBFs) are commonly used for food aid. Sorghum and cowpeas have been suggested as alternative commodities because they are drought tolerant, s...
Colicin concentrations inhibit growth of Escherichia coli O157:H7 in vitro.

Escherichia coli O157:H7 is a virulent foodborne pathogen that causes severe human illness and inhabits the intestinal tract of food animals. Colicins are antimicrobial proteins produced by E. coli strains that inhibit or kill other E. coli. In the present study, the efficacy of three pore-forming colicins (E1, N, and A) were quantified in vitro against E. coli O157:H7 strains 86-24 and 933. Colicins E1 and N reduced the growth of E. coli O157:H7 strains, but the efficacy of each colicin varied among strains. Colicin E1 was more effective against both strains of E. coli O157:H7 than colicins A and N and reduced (P < 0.05) populations of E. coli O157:H7 at concentrations <0.1 μg/ml. These potent antimicrobial proteins may potentially provide an effective and environmentally sound preharvest strategy to reduce E. coli O157:H7 in food animals.
Thermal conductivity of rocksalt and other geologic materials from the site of the proposed waste isolation pilot plant

The measurements first reported by Acton on the thermal conductivity of samples taken from a borehole at the site of the proposed nuclear waste isolation pilot plant (WIPP) near Carlsbad, NM, have been extended to include additional samples and higher temperature measurements. Samples for our measurements were taken from several depths of three wells, including the well AEC 8 from which Acton obtained his samples. These samples ranged from relatively pure rocksalt (NaCl) with small amounts of interstitial anhydrite to essentially nonsalt samples composed of gypsum or clay. The measurements in this latest series were conducted at Sandia using the longitudinal heat flow apparatus described by Acton, at the Los Alamos Scientific Laboratory (LASL) using a transient line source technique and at Dynatech Corp., Cambridge, MA, using a linear heat flow comparative technique.
CSR data collection pilot

The objective of the CSR Corpus Development is to collect and deliver a large corpus of continuous speech data to support DARPA research efforts in continuous speech recognition (CSR). The CSR corpus is intended to be task independent and to consist of speech that is similar to that which would be expected from eventual users of real world CSR systems. Toward these ends, the current pilot collection effort was designed to minimize controls on vocabulary, background noise, and microphones. CSR is also designed to incorporate spontaneous speech.
Informed consent for cataract surgery: patient understanding of verbal, written, and videotaped information.

Purpose To determine the effectiveness of verbal, written, and videotaped descriptions of cataract surgery on patients’ understanding of the risks, benefits, and treatment alternatives. Setting Veterans Affairs Boston Healthcare System, Boston, Massachusetts, USA. Design Randomized prospective study. Methods Patients eligible for cataract surgery were randomized into 1 of 4 arms of the informed consent process as follows: Group 1, conventional verbal information; Group 2, conventional verbal information plus second-grade reading level brochure; Group 3, conventional verbal information plus eighth-grade reading level brochure; Group 4, conventional verbal information plus American Academy of Ophthalmology DVD Understanding Cataract Surgery: Patient Education DVD Featuring an Aid to Informed Consent. After the informed consent process, patients in each group completed a 12-question questionnaire discussing the surgical procedure, its benefits, its foreseeable and unforeseeable risks, and the alternatives to cataract surgery. Scores in each group were calculated as the number of correct responses out of 12 questions. Results Patients in Group 2 (mean score 10.8 ± 1.29 [SD]) and Group 4 (mean score 10.56 ± 1.44) scored significantly higher than patients in Group 1 (mean score 7.68 ± 2.80) or Group 3 (mean score 9.08 ± 1.60). Previous cataract surgery and education level had no significant influence on recall of the informed-consent process. Conclusions Concise informed consent information sheets at lower reading grade levels and videotape presentation optimized patient understanding of the risks, benefits, and treatment alternatives to cataract surgery. The cost–benefit of these results is important because better patient understanding has the potential to decrease the risk for indemnity payments awarded because of inadequate informed consent. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.
Homeostatic Regulation of Kv1.2 Potassium Channel Trafficking by Cyclic AMP

The Shaker family potassium channel, Kv1.2, is a key determinant of membrane excitability in neurons and cardiovascular tissue. Kv1.2 is subject to multiple forms of regulation and therefore integrates cellular signals involved in the homeostasis of excitability. The cyclic AMP/protein kinase A (PKA) pathway enhances Kv1.2 ionic current; however, the mechanisms for this are not fully known. Here we show that cAMP maintains Kv1.2 homeostasis through opposing effects on channel trafficking. We found that Kv1.2 is regulated by two distinct cAMP pathways, one PKA-dependent and the other PKA-independent. PKA inhibitors elevate Kv1.2 surface levels, suggesting that basal levels of cAMP control steady-state turnover of the channel. Elevation of cAMP above basal levels also increases the amount of Kv1.2 at the cell surface. This effect is not blocked by PKA inhibitors, but is blocked by inhibition of Kv1.2 endocytosis. We conclude that Kv1.2 levels at the cell surface are kept in dynamic balance by opposing effects of cAMP.
A 4 μW dual-modulus frequency divider with 198 % locking range for MICS band applications

This paper presents the design and performance of an ultra-low-power 4/5 frequency divider based on a CMOS ring oscillator. Measurements show a 198 % locking range (6 MHz---1.3 GHz) for both division ratios at room temperature, covering the MICS band and 433 and 915 MHz ISM bands while consuming only 4.07 μW from a 1 V supply at 400 MHz. The wide locking range and low power consumption makes it very suitable for ultra-low-power wireless systems. The divider is fabricated in a 90 nm CMOS process and occupies 45 μm2 of area.
Cis-Trans Photoisomerization of the 1,6-Diphenyl-1,3,5-hexatrienes in the Triplet State. The Quantum Chain Mechanism and the Structure of the Triplet State†

Fluorenone sensitization in solution interconverts all-trans-1,6-diphenyl-1,3,5-hexatriene (ttt-DPH) with its trans,cis,trans, cis,trans,trans, and cis,cis,trans (trace) isomers, tct-, ctt-, and cct-DPH, respectively. Photoisomerization quantum yields are reported for the three major isomers in degassed and air-saturated benzene. In degassed solutions the quantum yields are strongly concentration dependent due to quantum chain processes. The presence of air eliminates the quantum chain processes, as all DPH triplets are deactivated by oxygen. Triplet−triplet absorption spectra observed in the microsecond time scale starting from these three DPH isomers are identical. The concentration dependence of the DPH triplet lifetime is consistent with the concentration dependence of the isomerization quantum yields. The results indicate that in benzene DPH triplets exist as an equilibrium mixture of ttt, tct, and ctt isomers whose composition at 20 °C, 94% ttt, 5% tct, and 1% ctt is revealed by isomerization quantu...
Levels of free amino acids in excitatory, inhibitory and sensory axons of the walking limbs of the lobster.

Abstract Using a gas chromatography procedure, the levels of several amino acids were determined in individual excitatory and inhibitory axons, in bundles of sensory fibers, and in muscle tissue from the walking limb of the lobster, Homarus americanus . In addition, the levels of amino acids in the hemolymph were also determined. Of the amino acids assayed in the excitatory and inhibitory axons and in the sensory fibers the level of aspartate was highest whereas in hemolymph and muscle, aspartate had one of the lowest values. The levels of glutamate, glycine and proline were significantly higher in the excitatory axons than in the inhibitory axons. GABA was present in inhibitor axons and in the muscle tissue which these axons innervate and was not detected in the other axons assayed nor in the hemolymph. β-Alanine was present at low levels in hemolymph and in muscle but was not detected in the excitatory nor in the inhibitory axons.
Perianal Paget's Disease: A Histologic and Immunohistochemical Study of 11 Cases With and Without Associated Rectal Adenocarcinoma

Perianal Paget's disease is rare, and its relationship to an associated internal regional cancer has been ill defined. We analyzed the histologic and immunohistochemical features of perianal Paget's disease in 11 patients to determine the frequency and relationship of associated regional internal carcinoma and to gain insight into its histogenesis. Of five patients with documented rectal adenocarcinoma, it was discovered synchronously with the Paget's disease in four and, subsequently, in one. Paget's cells of signet ring type predominated in four cases. Intraepithelial glands with intraluminal dirty necrosis were present in four cases. The immunophenotype in four cases studied was cytokeratin (CK)7+/CK20+/gross cystic disease fluid protein- (GCDFP) in both the intraepithelial Paget's cells and the invasive rectal adenocarcinoma. Six patients did not have documented rectal carcinoma. The Paget's cells in four were CK7+/CK20-/GCDFP15+. Three of these had purely intraepithelial Paget's disease, and invasive or metastatic disease developed in none after wide local excision. Bilateral inguinal lymph node metastases developed in the fourth patient, and the patient died 8 months after diagnosis of Paget's disease. In two patients, the Paget's cells were CK7+/CK20+/GCDFP15-. Recurrent intraepithelial perianal Paget's disease developed in one patient at 7 months; the patient was alive without disease at 24 months, and the other patient had several intraepithelial recurrences of perianal Paget's disease, and, subsequently, a large perianal tumor of uncertain cell type developed at 108 months, which led to the patient's death. We conclude that there are two types of perianal Paget's disease. One type has endodermal differentiation with gastrointestinal-type glands containing intraluminal dirty necrosis, numerous signet ring cells, CK20 positivity, and GCDFP15 negativity. Such cases are especially likely to be associated with synchronous or metachronous rectal adenocarcinoma. The other type is a primary cutaneous intraepithelial neoplasm in which the Paget's cells display sweat gland differentiation, including GCDFP15 positivity; it generally lacks gastrointestinal-type glands, intraluminal dirty necrosis, and CK20 positivity. The CK7 is a sensitive, albeit nonspecific, marker for Paget's cells.
Stress management effects on perceived stress and cervical neoplasia in low-income HIV-infected women

Abstract Objective Risk for developing cervical neoplastic disease is greatly increased in women infected with oncogenic sexually transmitted human papillomaviruses (HPVs) and who have lowered cellular immunity due to coinfection with human immunodeficiency virus (HIV) infection. The majority of these individuals are low-income minority women. Factors associated with promotion of HPV to cervical neoplasia in HIV-infected populations include degree of immunosuppression as well as behavioral factors such as tobacco smoking and psychological stress. This study examined the effects of a cognitive behavioral stress management (CBSM) intervention on life stress and cervical neoplasia in HIV+ minority women. Methods Participants were 39 HIV+ African-American, Caribbean, and Hispanic women with a recent history of an abnormal Papanicolaou smear. Participants underwent colposcopic examination, psychosocial interview, and peripheral venous blood draw at study entry and 9 months after being randomly assigned to either a 10-week CBSM group intervention ( n =21) or a 1-day CBSM workshop ( n =18). Results Women assigned to the 10-week group-based CBSM intervention reported decreased perceived life stress and had significantly lower odds of cervical neoplasia over a 9-month follow-up. CBSM effects on life stress and neoplasia appeared independent of presence of neoplasia at study entry, HPV type, CD4+CD3+ cell count, HIV viral load, and substance use. Furthermore, CBSM intervention effects on cervical neoplasia were especially pronounced among women with residual life stress at follow-up. Conclusion These findings suggest that stress management decreases perceived life stress and may decrease the odds of cervical neoplasia in women with HIV and a history of abnormal Papanicolaou smears. Although preliminary, these findings suggest the utility of stress management as a cancer prevention strategy in this high-risk population.
Hybrid image-/model-based gaze-contingent rendering

A nonisotropic hybrid image-/model-based gaze-contingent rendering technique utilizing ray casting on a GPU is discussed. Empirical evidence derived from human subject experiments indicates an inverse relationship between a peripherally degraded scene's high-resolution inset size and mean search time, a trend consistent with existing image- and model- based techniques. In addition, the data suggest that maintaining a target's silhouette edges decreases search times when compared to targets with degraded edges. Benefits of the hybrid technique include simplicity of design and parallelizability, both conducive to GPU implementation.
Continuous Reversible Addition-Fragmentation Chain Transfer Polymerization in Miniemulsion Utilizing a Multi-Tube Reaction System

A unique, multi-tube, continuous reactor has been successfully designed and implemented for the study of reversible addition-fragmentation chain transfer (RAFT) in miniemulsions. Data collection is greatly enhanced by the ability to simultaneously collect samples at five different residence times. The results of a styrene homopolymerization show that kinetically, the reactor exhibits similar behavior to a batch reaction. Number-average molecular weights increased linearly with conversion, typical of living polymerizations.
Dedicated minimally invasive surgery suites increase operating room efficiency.

Background: The rapid adoption of laparoscopic surgery since the late 1980s added tremendous complexity into the operating room (OR) environment. For each case, a plethora of additional equipment-including monitors, video equipment, wiring, tubing, and cords-had to be set up, prolonging OR turnover time and decreasing OR efficiency. In 1993, the concept of designated minimally invasive surgery (MIS) suites was introduced. MIS suites integrated monitors and video equipment into the OR on ceiling-mounted columns and moved the controls to a centralized nursing station. The overall effect of this innovation on OR efficiency has not been measured. Methods: Five RNs with varying degrees of MIS experience were instructed on video setup and put-away criteria and then timed while performing a set of standardized tasks. Each set of tasks was performed twice using a standardized surgery model. Differences in setup and put-away times between MIS suites and standard ORs were tested using the t-test for paired comparisons. Results: The mean ± standard deviation (SD) video setup times were 27.9 ± 5.3 sec (MIS) and 254.3 ± 54.0 sec (standard); the put-away times were 19.8 ± 2.7 sec (MIS) and 222.3 ± 26.0 sec (standard). The mean difference ± standard error (SE) in both the setup (226.4 ± 16.9 sec, p = 0.0001) and put-away times (202.5 ± 8.6, p = 0.0001) were large and statistically significant. Conclusion: Using a simulation model, we have demonstrated that the use of a MIS suite reduces video setup and put-away time significantly, with the potential for significant associated cost savings. This provides just one justification for the high cost of building such "ORs of the future."
VO2 thin films: Defect mediation in room temperature ferromagnetic switching characteristics

Vanadium dioxide (VO2) has tremendous potential in multifunctional device applications related to spintronics, switching, and magnetic recording. We have discovered that the room temperature ferromagnetism (RTFM) in undoped vanadium oxide epitaxial films can be switched on and off by altering the cooling ambient conditions which exhibit a sharp electrical transition at 341 K. By correlating the structural and ferromagnetic properties in VO2, we envisage the potential for creation of novel multifunctional solid-state devices. High-quality epitaxial VO2 thin films were grown on c-sapphire (0001) substrates, under different ambient conditions via the domain matching epitaxy paradigm. The observed RTFM has its origin in the valence charge defects with unpaired electrons in V+3 in VO2 thin films, where the concentration of the defects could be varied with oxygen partial pressure. The VO2 films-with a high ferro- to paramagnetic transition (Curie) temperature around 500 K estimated by fitting the magnetization data to the Bloch’s T3/2 law, a saturated magnetization of 18 emu/cm3, and with a finite coercivity of 40 Oe at 300 K-can be useful for integrated smart sensors operable at room temperature.
Photoinduced non-linear optical diagnostic of SiNxOy/Si〈111〉 interfaces

Anisotropic (elliptically polarized) photoinduced second harmonic generation (PISHG) in SiNxOy/Si〈111〉 films was proposed for contact-less monitoring of specimens with different nitrogen to oxygen (N/O) ratios. As a source for the photoinducing light, we used a nitrogen Q-switched pulse laser at wavelengths of 315, 337 and 354nm as well as doubled frequency YAG–Nd laser wavelength (λ=530nm). The YAG : Nd pulse laser (λ=1.06μm;W=30MW;τ=10–50ps) was used to measure the PISHG. All measurements were done in a reflected light regime. We found that the output PISHG signal was sensitive to the N/O ratio and the film thickness. Measurements of the PISHG versus pumping wavelengths, powers, incident angles as well as independent measurements of the DC-electric field induced second harmonic generation indicate the major role played in this process by axially symmetric photoexcited electron–phonon states. The SiNxOy films were synthesized using a technique of chemical evaporation at low pressures. Films with thickness varying between 10 and 30nm and with an N/O ratio between 0 and 1 were obtained. Electrostatic potential distribution at the Si〈111〉–SiNxOy interfaces was calculated. Comparison of the experimentally obtained and quantum chemically calculated PISHG data are presented. High sensitivity of anisotropic PISHG to the N/O ratio and film thickness is revealed. The role of the electron–phonon interactions in the dependencies observed is discussed. We have shown that the PISHG method has higher sensitivity than the traditional extended X-ray absorption fine structure spectroscopic and linear optical method for films with the N/O ratio higher than 0.50.
Comment on “Proposal for Raman X-ray free electron laser”

Equation 13 in this paper defines the force experienced by the electron moving in z direction with velocity v{sub z} due to the X-ray wave propagating in z direction with electric field E{sub 1} pointing in y direction and magnetic field B{sub 1} pointing in x direction as {rvec F}{sub 1}(t) = -eE{sub 1} cos({omega}{sub 1}t - k{sub 1}z){rvec e}{sub y}. In our opinion calculating this force one should also include the impact of the X-ray wave's magnetic field and obtain {rvec F}{sub 1}(t) = -e E{sub 1} = v{sub z}/c B{sub 1} cos({omega}{sub 1}t - k{sub 1}z){rvec e}{sub y} {approx} - eE{sub 1}/2{gamma}{sup 2} cos({omega}{sub 1}t - k{sub 1}z){rvec e}{sub y}. Here c is the speed of light and {gamma} is the electron relativistic factor. In result one would need to change E{sub 1} to E{sub 1}/2{gamma}{sup 2} in all the following equations in the cited paper (except wave propagation equations, Eqs. (23) and (34)). They believe that similar omission in the impact of the magnetic field appears in equation (28). Consequently, the formula for the gaion (Eq. (37) in the cited paper) should also include the factor 1/2{gamma}{sup 2}. This is a rather significant modification considering that relativisticmore » electrons with values of {gamma} ranging from approximately 20 to approximately 300 are used in the numerical examples.« less
Atmospheric Pollution: History, Science and Regulation

There is no shortage of textbooks available for introductory courses on air pollution. However, finding a text that is ideally suited for a specific course can be nearly impossible, since the focus of the text never quite matches what you want to teach in the course. Atmospheric Pollution: History, Science and Regulation, by Mark Z. Jacobson, provides a novel perspective on air pollution by examining the historical developments of air pollution science and regulation prior to presenting information on the major air pollution issues of today. The first two chapters set the stage for studying the atmosphere from a historical context. In the first chapter, the basics of atmospheric gases and particles are defined, and the topic progresses to a historical accounting of the discoveries of the important atmospheric chemicals. The author discusses the experiments that determined the composition of the various trace gases present in the atmosphere, and how the misinterpretation of some experiments led to incorrect conclusions about the makeup of atmospheric trace gases. The second chapter focuses on the evolution of the Earth's atmosphere, beginning at the time of formation of the Sun and Earth, the evolution of a pre-biotic atmosphere into an anoxic biotic atmosphere, and finally the evolution of oxygen through photosynthesis. This material provided new insight into how trace gases were first discovered and how the atmosphere evolved. While this might be fascinating to someone who has spent years studying the present-day atmosphere, it may not necessarily be important in an introductory course.
Common Hydrogen Bond Interactions in Diverse Phosphoryl Transfer Active Sites

Phosphoryl transfer reactions figure prominently in energy metabolism, signaling, transport and motility. Prior detailed studies of selected systems have highlighted mechanistic features that distinguish different phosphoryl transfer enzymes. Here, a top-down approach is developed for comparing statistically the active site configurations between populations of diverse structures in the Protein Data Bank, and it reveals patterns of hydrogen bonding that transcend enzyme families. Through analysis of large samples of structures, insights are drawn at a level of detail exceeding the experimental precision of an individual structure. In phosphagen kinases, for example, hydrogen bonds with the O3β of the nucleotide substrate are revealed as analogous to those in unrelated G proteins. In G proteins and other enzymes, interactions with O3β have been understood in terms of electrostatic favoring of the transition state. Ground state quantum mechanical calculations on model compounds show that the active site interactions highlighted in our database analysis can affect substrate phosphate charge and bond length, in ways that are consistent with prior experimental observations, by modulating hyperconjugative orbital interactions that weaken the scissile bond. Testing experimentally the inference about the importance of O3β interactions in phosphagen kinases, mutation of arginine kinase Arg280 decreases kcat, as predicted, with little impact upon KM.
Ethnic background and in vitro fertilization outcomes.

Abstract Objective To compare IVF outcomes among women of different ethnic backgrounds. Method This was a retrospective cohort study. Between August 1994 and March 1998, the first IVF cycles of 1039 white, 43 African American, 18 Hispanic, and 35 Asian women were examined. Result Ages and day 3 FSH levels did not differ significantly among patients. African Americans weighed more than other ethnic groups and were also more likely to have tubal factor infertility than whites. IVF cycle characteristics did not vary among the ethnic groups with the exception that African Americans had a higher level of estradiol on day of HCG than whites. Pregnancy outcomes did not differ among the ethnic groups. The percentage of ectopic pregnancies, spontaneous abortions, and successful live births was similar among the groups. Conclusion Our data showed no significant difference in pregnancy outcomes with IVF among the ethnic groups.
Recent advances in macromolecular hydrodynamic modeling.

Abstract The modern implementation of the boundary element method [23] has ushered unprecedented accuracy and precision for the solution of the Stokes equations of hydrodynamics with stick boundary conditions. This article begins by reviewing computations with the program BEST of smooth surface objects such as ellipsoids, the dumbbell, and cylinders that demonstrate that the numerical solution of the integral equation formulation of hydrodynamics yields very high precision and accuracy. When BEST is used for macromolecular computations, the limiting factor becomes the definition of the molecular hydrodynamic surface and the implied effective solvation of the molecular surface. Studies on 49 different proteins, ranging in molecular weight from 9 to over 400 kDa, have shown that a model using a 1.1 A thick hydration layer describes all protein transport properties very well for the overwhelming majority of them. In addition, this data implies that the crystal structure is an excellent representation of the average solution structure for most of them. In order to investigate the origin of a handful of significant discrepancies in some multimeric proteins (about −20% observed in the intrinsic viscosity), the technique of Molecular Dynamics simulation (MD) has been incorporated into the research program. A preliminary study of dimeric α-chymotrypsin using approximate implicit water MD is presented. In addition I describe the successful validation of modern protein force fields, ff03 and ff99SB, for the accurate computation of solution structure in explicit water simulation by comparison of trajectory ensemble average computed transport properties with experimental measurements. This work includes small proteins such as lysozyme, ribonuclease and ubiquitin using trajectories around 10 ns duration. We have also studied a 150 kDa flexible monoclonal IgG antibody, Trastuzumab, with multiple independent trajectories encompassing over 320 ns of simulation. The close agreement within experimental error of the computed and measured properties allows us to conclude that MD does produce structures typical of those in solution, and that flexible molecules can be properly described using the method of ensemble averaging over a trajectory. We review similar work on the study of a transfer RNA molecule and DNA oligomers that demonstrate that within 3% a simple uniform hydration model 1.1 A thick provides agreement with experiment for these nucleic acids. In the case of linear oligomers, the precision can be improved close to 1% by a non-uniform hydration model that hydrates mainly in the DNA grooves, in agreement with high resolution X-ray diffraction. We conclude with a vista on planned improvements for the BEST program to decrease its memory requirements and increase its speed without sacrificing accuracy.
MOS Pass transistor turn-off transient analysis

Errors induced by turn-off transients are one fundamental limit in precision switched capacitor circuits. This paper presents detailed pass transistor turn-off transient analysis. Conventional single-lump models which assume quasi-static operation can introduce substantial errors for high-speed analog applications. New distributed and two-lump models have been constructed to analyze pass transistor turn-off transients in the diffusion mode of operation. A pass transistor test chip including a new selectively doped pass transistor approach has been designed, fabricated, and tested to verify the transient analysis. Measured performance of the nonuniformly doped pass transistors shows advantages in reducing transient charge errors.
Effects of diethylmaleate on DNA damage and repair in the mouse brain

The enzyme 8-oxoguanine DNA glycosylase 1 participates in the repair of damaged DNA by excising the oxidized base 8-hydroxy-2'-deoxyguanosine. We have previously demonstrated that enzymatic activity of this enzyme is inversely related to the levels of the damaged base in specific brain regions. We now report that the activity of 8-oxoguanine DNA glycosylase 1 is increased in a region-specific manner following treatment with diethylmaleate, a compound that reduces glutathione levels in the cell. A single treatment with diethylmaleate elicited a significant increase ( approximately 2-fold) in the activity of 8-oxoguanine DNA glycosylase 1 in three brain regions with low basal levels of activity (cerebellum, cortex, and pons/medulla). There was no change in the activity of 8-oxoguanine DNA glycosylase 1 in those regions with high basal levels of activity (hippocampus, caudate/putamen, and midbrain). This is the first report to demonstrate that DNA repair capacity can be upregulated in the CNS, and the increased repair activity correlates with a reduction in the levels of DNA damage. The brain region-specific capacity to deal with increased oxidative damage to DNA may be responsible, in part, for the vulnerability of specific neuronal populations with aging, sources of oxidative stress, and neurodegenerative diseases.
Susceptibility and Mechanisms Underlying the Relative Tolerance to Five Organophosphorus Insecticides in Tobacco Budworms and Corn Earworms

Abstract Laboratory investigations were conducted to explain the higher insecticide tolerance in tobacco budworm (TBW) relative to corn earworm (CEW). The acute toxicities of five organophosphorus (OP) insecticides to TBW and CEW laboratory colonies were first measured using a standard topical application procedure. In vivo inhibition of acetylcholinesterase (AChE) and aliesterases (AliE) by the five compounds was determined for both species. In vitro inhibition of acetylcholinesterase and aliesterases by the corresponding oxons was also determined. With the exception of profenofos, all OPs were more toxic to the CEW colony than to the TBW colony. The tolerance ratios ranged from 1.3 for profenofos to 18.3 for chlorpyrifos. No significant differences in the amount of AChE activity in the two species were found. In vitro AChE inhibition studies revealed that AChE of the TBW colony had a lower sensitivity to inhibition by most of the oxons than that of the CEW colony. AChE sensitivity varied among different OPs but did not correlate with toxicity. Aliesterase activity toward three substrates (4-nitrophenyl butyrate, 4-nitrophenyl valerate, and 1-naphthyl butyrate) at three larval ages (small, medium, and large) was found to be significantly greater in the TBW colony than in the CEW colony. There was no significant difference in protein content in the two species, except in medium-size larvae. Substrate specificity of aliesterase from both species was 4-nitrophenyl butyrate > 1-naphthyl butyrate > 4-nitrophenyl valerate. All oxons except methyl paraoxon were potent in vitro inhibitors of AliE. However, TBW AliEs were less sensitive to inhibition than those of CEW. Both TBW and CEW larval homogenates increased the I 50 of both paraoxon and chlorpyrifos oxon to bovine brain AChE, indicating that the oxons were detoxified by larval homogenates. Percentage detoxication was higher for TBW than for CEW and was greater for chlorpyrifos oxon than for paraoxon. In TBW, the AliE inhibitor DEF ( S,S,S -tributyl phosphorothioate) synergized both methyl parathion and chlorpyrifos, and the level of synergism correlated with anti-AliE activity of the insecticide alone. Thus, a combination of lower sensitivity of AChE and higher specific activity and detoxication capacity of AliE appear to largely explain the higher degree of insecticide tolerance in tobacco budworm than in corn earworm.
Exact solutions for a discrete system arising in traffic flow

This paper concerns wave propagation in a discrete nonlinear system of equations proposed and studied by G. F. Newell as a model for car-following in traffic flow. In particular, Newell found exact solutions for shock waves and related phenomena. Here, exact solutions representing periodic waves and solitary waves are obtained. The method relates travelling wave solutions to the Toda and Kac-van-Moerbeke discrete systems. In this and other ways, much of the interest is in the general phenomena possible in discrete systems, here including also a time lag, rather than in just the specific traffic flow setting.
A physicochemical approach to improving free fat graft survival: preliminary observations.

A different experimental approach to the problem of post-transplantation free fat graft resorption was evaluated. Bioactive free fat grafts were created through the addition of basic fibroblast growth factor (bFGF) carried on positively charged, hydrophilic, dextran beads to the grafts. This bioactive graft was compared with contralateral free fat grafts in the lateral facial areas of mature rats. After 90 days, when compared with the body mass increase of the animals, complete retention of the bioactive fat grafts occurred in contrast to the free grafts that exhibited loss of nearly half of their original weight. The histologic findings of small-sized adipocytes or adipocyte buds among larger adipocytes in the bioactive grafts raise the possibility of activation and induced differentiation of a preadipocyte cell line in these grafts.
Apatia e alheamento político numa sociedade paralisada: os limites da nova democracia chilena

The notion of a "stalemate society" used here to describe contemporary Chilean democracy is meant to suggest a particular political system where the likelihood of significant change resulting through elections and bargaining has been reduced to a minimum. Given restrictive political provisions imposed by the Pinochet military regime upon the new democracy such as the constitutionally-sanctioned appointed Institutional Senators and the "binomial" election law which dramatically over-represents the largest minority group one can argue that political power was meant to be almost equally divided between those center and center-left forces grouped in the Concertacion coalition and those opposing them on the political right, in seeming disregard of what the voters wanted. What is raised as the central question for examination in this essay relates to the likely effects such entrenched political immobilism may have had on Chileans as they became aware that the political forces representing a popular majority had only a limited ability to achieve the changes sought. The type of effect suggested here focuses on existing political apathy and alienation.
Microstructures of Butadiene Copolymers Determined by Ozonolysis/MALDI Mass Spectrometry

Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry of ozonolysis degradation products was used to determine the microstructures of several butadiene copolymers. A random styrene−butadiene copolymer containing 45 wt % styrene was distinguished from a block (ABA) styrene−butadiene copolymer containing 38 wt % styrene. In addition, several acrylonitrile−butadiene copolymers with acrylonitrile contents ranging from 21 to 51 wt % were analyzed. The microstructures for the acrylonitrile−butadiene copolymers were confirmed to be fairly random. Quantitatively, the acrylonitrile compositions determined by ozonolysis/MALDI-MS were close to the reported values for these copolymers (typically within 5 wt %). The discrepancy between the reported and experimentally obtained compositions may be attributed, in part, to a composition bias arising from the ozonolysis process. A simple model for ozonolysis of a random copolymer was developed to investigate the effects of ozone exposure time on the oligome...
The effects of x-irradiation on the DNA of Escherichia coli. An autoradiographic study.

Abstract Cells of a radiation resistant strain (B/r) and a radiation sensitive strain (B s−1 ) of Escherichia coli were labeled with 3 H thymidine. Quantitative autoradiography was used to compare the distribution of radioactivity among unirradiated and X-irradiated cells. During a 50 min incubation all irradiated cells, including survivors in the resistant strain, lost labeled material. The radiation sensitive cells lose much more label than the resistant ones.
Frequency standards based on atomic hydrogen

The current state of hydrogen maser frequency standards is briefly reviewed. Particular emphasis is placed on the discussion of physical mechanisms which affect long-term stability. While questions concerning absolute accuracy still remain, recent experiments suggest that long-term stability can be at least as good as the best primary standards (1 × 10-13/year). This long-term stability can be realized by small passive hydrogen maser field standards, a fact which makes these attractive alternatives to cesium field standards. Hydrogen masers already exhibit the best short-term stability of any room-temperature atomic clock and this could be improved by a factor of 100 with the development of hydrogen masers operating at cryogenic temperatures.
Intersectional Stigma and the Acceptance Process of Women with Mental Illness

Acceptance of mental illness is facilitated by the presence of various resources that are needed to deal with associated stigma, prejudice, and discrimination. However, women with mental illness experience added levels of stigma and intersectional oppression that affect the acceptance process, including higher rates of victimization, unemployment, poverty, homelessness, and clinical disparities. Practitioners and researchers can benefit from sensitivity to intersectional stigma, or overlapping, multiple levels of stigma and discrimination, faced by women with mental illness. Participant case narratives from a qualitative study will be presented in order to demonstrate the impact of intersectional stigma on the process of acceptance for women with mental illness.
PURIFICATION OF BOVINE THYROTROPIC HORMONE BY ION EXCHANGE CHROMATOGRAPHY

Previous chemical work directed toward isolation of the thyrotropic hormone from the anterior pituitary (usually bovine) has almost always depended upon precipitation methods of purification (Janssen and Loeser, 1931; Junkmann and Schoeller, 1932; Loeser, 1932; Greep, 1935; Lambie and Trikojus, 1937; Bonsnes and White, 1940; Fevold et al., 1940; Fraenkel-Conrat et al., 1940; Ciereszko, 1945). A number of reagents used in the fractionation of various proteins have been applied to crude extracts; thyrotropin has been found to be soluble in dilute but precipitated in concentrated aqueous solutions of common organic solvents (Janssen and Loeser, 1931; Junkmann and Schoeller, 1932; Loeser, 1932; Bonsnes and White, 1940; Fraenkel-Conrat et al., 1940; Ciereszko, 1945) and salts (Fevold et al., 1940; Fraenkel-Conrat et al., 1940), and it has been precipitated by various organic acids, heavy metal salts, and other protein precipitants (Loeser, 1932). Lack of both specificity and selectivity is the essential limita...
The influence of patriarchal ideology on outcomes of legal decisions involving woman battering cases: an analysis of five historical eras

Abstract Numerous qualitative analyses suggest that our legal system has been dominated by a patriarchal ideology that has affected judges’ legal decisions on cases pertaining to woman battering. To provide a quantitative test, we analyzed legal opinions from five historical eras to determine if the number of indicators of patriarchal ideology has changed over time. We also performed logistic regression analyses to determine whether these indicators are actually associated with case outcomes. Consistent with our hypotheses, in the most recent era (a) there has been a decrease in two of the indicators of patriarchal ideology (judges are less likely to assume that the woman was the instigator and they are less likely to make internal attributions to the woman), (b) the probability of battered women winning these cases has increased, and (c) the best predictor of case outcome is the extent to which the judge believes the woman was the instigator. However, we also obtained evidence that the drawbacks of patriarchal ideology may have affected some men, as well as women, in a negative way.
DEFECTIVE HSV-SPECIFIC IMMUNITY FOLLOWING NEONATAL HSV ENCEPHALITIS

With effective anti-viral therapy increasing numbers of infants are surviving neonatal herpes simplex virus infections. Some survivors have recurrent HSV skin lesions, suggesting a relative deficiency of their HSV-specific immunity. To test this we used limiting dilution assays to determine the frequency of HSV specific T lymphocytes in the blood of healthy children and adults and survivors of neonatal HSV encephalitis. The subjects' serum IgG and IgM anti-HSV antibodies were determined independently by ELISA. 30% of randomly selected children aged 18 months - 12 years had HSV antibody and all of these had HSV-responsive lymphocytes in the blood with a frequency of 1:7,000 to 1:15,000. 80% of healthy adults were antibody positive and their responder lymphocyte frequencies were 1:10,000 to 1:20,000. Responder cell frequencies in antibody negative children or adults were 1:200,000 or less. The neonatal HSV survivors were aged 6 months - 7 years. All had IgG and IgM HSV antibodies but their T cell responder frequencies were 1:30,000 or less. Monocyte defects and antigen-specific immunosuppression were excluded as explanations for the low responder cell frequencies by in vitro cultures. These results suggest that the survivors of neonatal HSV may, like the survivors of congenital or neonatal CMV, have a deficiency of HSV specific T4+ cells due presumably to central failure of production or to lack of clonal expansion.
SOCIAL LEARNING THEORY AND NONMEDICAL PRESCRIPTION DRUG USE AMONG ADOLESCENTS

Adolescent substance use is an important area of research in sociology; however, there is a lack of research on nonmedical prescription drug use. The dearth of research on this topic is problematic given the relatively high prevalence of use among adolescents, the drastic increase in use in recent years, and the potential negative consequences from misusing prescription drugs. Using data from a national sample of adolescents, this research fills an important gap in the literature by testing one of the most prominent theories of deviance: social learning theory. Findings support variables related to social learning theory as correlates of nonmedical prescription drug use. Adolescents with definitions that are pro-substance use, whose peers use drugs, and whose parents and peers have attitudes that condone substance use are more likely to report nonmedical prescription drug use in the past year. Important implications and future research directions are discussed.
Floral visitation by the Argentine ant reduces bee visitation and plant seed set

Ants often visit flowers, but have only seldom been documented to provide effective pollination services. Floral visitation by ants can also compromise plant reproduction in situations where ants interfere with more effective pollinators. Introduced ants may be especially likely to reduce plant reproductive success through floral visitation, but existing experimental studies have found little support for this hypothesis. Here, we combine experimental and observational approaches to examine the importance of floral visitation by the nonnative Argentine ant (Linepithema humile) on plant species native to Santa Cruz Island, California, USA. First, we determine how L. humile affects floral visitor diversity, bee visitation rates, and levels of pollen limitation for the common, focal plant species island morning glory (Calystegia macrostegia ssp. macrostegia). Second, we assess the broader ecological consequences of floral visitation by L. humile by comparing floral visitation networks between invaded and unin...