cssi/SciSciGPT-SciSciNet huggingface dataset:
SPATIO-TEMPORAL DISCRIMINATION OF FREQUENCY IN THE RIGHT AND LEFT VISUAL FIELDS: A PRELIMINARY REPORT

Summary.-Normal right-handed subjects were presented with luminance patterns varying sinusoidally in both space and time to the lefr and right visual fields. With no temporal variation in the stimuli, detection thresholds for the left visual field were lower than those for the right visual field for all spatial frequencies. However, with increasing temporal variations, a reversal in detection of threshold occurred, with the right visual field surpassing the left. This finding suggests that left and right visual processing may be differentially efficient for temporal and spatial visual information. A large number of neuropsychological studies have produced results suggesting that the right hemisphere is superior in the parallel processing of information organized along spatial dimensions, while the left hemisphere possesses an advantage in the sequential processing of information organized along a temporal dimension (Bever & Chiarello, 1974; Cohen, 1973; Geffen, Bradshaw, & Wallace, 1971; Gordon, 1978; Kimura, 1966; Levy, Trevarthan, & Sperry, 1972; Nebes, 1974; Rizzolatti, Umilta, & Berlucchi, 1971). However, these studies utilized tasks of such high complexity that an analysis of these results in terms of neural processing might be premature. This preliminary study examined lateral differences using a psychophysical task which allows a more tenable explanation in terms of underlying neural processes and which is more closely related to current physiological research. Recently, the mathematics of linear systems, especially Fourier analysis, has been applied with considerable success in describing the transmission of spatial and temporal information in the visual system; for reviews, see DeValois and DeValois ( 1980), Kelly (1972) and Sekuler ( 1974). Specifically, it has been proposed that the human visual system is composed of multiple independent linear mechanisms, called "channels," each selectively tuned co a narrow range of spatial and temporal frequencies, and performing a Fourier transform on the stimulus input (Campbell & Robson, 1968; Kelly, 1972). Despite the extensive psychophysical and physiological experimentation in support of this approach, its application ro the study of hemispheric specialization has been neglected thus far in the research literature on vision. 'This srudy is based on a ponion of the first author's dissertation submitted to Wayne State Universia in 1979 in ~artial fulfillment of the requirements for the Ph.D. degree. We thank victor Pol, ~illiarn Milberg and Claude ~~gertsen for their assistance. -~equests for reprints may be sent to the first author's present address: Section of Neuropsychology, The Medical College of Wisconsin, Curative Rehabilitation Center, 9001 Warertown Plank Rd.. Milwaukee, Wisconsin 53226.
Intra-particle coating variability: Analysis and Monte-Carlo simulations

Abstract An analytical model is presented that describes the intra-particle coating variability of a single particle by a uniform spray. For uniformly random orientations, the film thickness coefficient of variation is proportional to the number of coating trials raised to the −1/2 power, and thus the coefficient of variation asymptotes to zero as the number of coating trials increases. However, if the particle has a preferred orientation while in the spray zone, the limiting value of the coefficient of variation is non-zero. Monte-Carlo simulations of a single particle subject to a coating spray are also presented and verify the theoretical model. Finally, analysis of discrete element method (DEM) computer simulations of spheres in a rotating, circular drum without baffles show that a sphere passing through the “spray zone” has an orientation corresponding to a preferred rotation from the sphere's orientation during its last past through the spray zone. Although the intra-particle coefficient of variation for orientations exhibiting this effect still asymptote to zero over time, the rate at which this occurs is smaller than that for uniformly random orientations.
Array Processors: A Selected Bibliography

This bibliography includes most of the trade journal articles, conference papers, and technical reports on array processors published in the English language since 1975. Generally, editorials are omitted, as are patents and specific device or system manuals. Also not included are unpublished papers and internal reports from industry, university, and government organizations where most array processors are installed.
Converging methods in developmental science: an introduction.

This special issue of Developmental Psychobiology reflects a number of recent advances in the field of developmental neuroscience. The most evident are methodological advances in noninvasive neuroimaging such as those described in a parallel special issue of Developmental Science, Volume 5, 2002. While advances in imaging methods offer a new era in developmental research, other methods (e.g., animal, computational, lesion, and genetic) remain essential in constraining and informing theories of brain and behavioral development. The papers in this issue highlight the importance of a converging methods approach to the study of developmental science and illustrate how a variety of available tools allow insights into both new and classic developmental questions. © 2002 Wiley Periodicals, Inc. Dev Psychobiol 40: 197–199, 2002. DOI 10.1002/dev.10026
Endoscopic treatment of vesicoureteral refluxin children with neurogenic bladders

Abstract Endoscopic subureteral injection of Teflon was performed in 12 children (20 ureters)with neurogenic bladders and vesicoureteral reflux (grades III–IV). Follow-up evaluation by ultrasonography and voiding cystourethrogram at three-month intervals up to two years revealed successful correction of the reflux in 70 percent of the ureters.
Context effects in speeded comprehension and recall of sentences

Effects of four types of context on sentence processing time and recall are examined. The results are consistent with Bransford and Johnson’s (1972, 1973) view that thematic or referential contexts facilitate comprehension by helping S to gain access to relevant prior knowledge. The results also suggest that context can speed sentence processing without influencing the semantic interpretation of the input.
Genotypic and allelic variability in CYP19A1 among populations of African and European ancestry

CYP19A1 facilitates the bioconversion of estrogens from androgens. CYP19A1 intron single nucleotide polymorphisms (SNPs) may alter mRNA splicing, resulting in altered CYP19A1 activity, and potentially influencing disease susceptibility. Genetic studies of CYP19A1 SNPs have been well documented in populations of European ancestry; however, studies in populations of African ancestry are limited. In the present study, ten ‘candidate’ intronic SNPs in CYP19A1 from 125 African Americans (AA) and 277 European Americans (EA) were genotyped and their frequencies compared. Allele frequencies were also compared with HapMap and ASW 1000 Genomes populations. We observed significant differences in the minor allele frequencies between AA and EA in six of the ten SNPs including rs10459592 (p<0.0001), rs12908960 (p<0.0001), rs1902584 (p = 0.016), rs2470144 (p<0.0001), rs1961177 (p<0.0001), and rs6493497 (p = 0.003). While there were no significant differences in allele frequencies between EA and CEU in the HapMap population, a 1.2- to 19-fold difference in allele frequency for rs10459592 (p = 0.004), rs12908960 (p = 0.0006), rs1902584 (p<0.0001), rs2470144 (p = 0.0006), rs1961177 (p<0.0001), and rs6493497 (p = 0.0092) was observed between AA and the Yoruba (YRI) population. Linkage disequilibrium (LD) blocks and haplotype clusters that is unique to the EA population but not AA was also observed. In summary, we demonstrate that differences in the allele frequencies of CYP19A1 intron SNPs are not consistent between populations of African and European ancestry. Thus, investigations into whether CYP19A1 intron SNPs contribute to variations in cancer incidence, outcomes and pharmacological response seen in populations of different ancestry may prove beneficial.
Beacons in the night : with the OSS and Tito's partisans in wartime Yugoslavia

1. To Slovenia by parachute 2. Preparing for the mission 3. First days with the partisans 4. Crossing the border 5. Inside the Third Reich 6. Blowing up Germany's railroads 7. Night marches and hidden hospitals 8. The partisans organise a shadow government 9. Radios, codes and codebreakers 10. Liberation of a mountain valley 11. The lure of Austria 12. Failure in Austria 13. Revolution comes into the open 14. The German winter offensive begins 15. Ethnic and ideological wars in Croatia 16. Tito's government takes control in Belgrade 17. The defeat of the Chetniks 18. Communist rule becomes absolute 19. The Cold War begins in Trieste 20. In the wake of the hot war 21. How it all turned out Appendix Notes Index.
Acyclovir prophylaxis in late pregnancy to prevent neonatal herpes: a cost-effectiveness analysis.

Objective: To compare the cost-effectiveness of oral acyclovir prophylaxis in late pregnancy to the current strategy of cesarean delivery for genital herpes lesions in the prevention of neonatal herpes transmission from mothers with recurrent genital infections. Methods: Decision analysis was used to evaluate the clinical outcomes and direct costs of a prevention program from the health care payer's perspective. Probabilities were obtained from the literature and experts. Cost data were based on hospital costs and a cohort of herpes-infected neonates. Results: Acyclovir prophylaxis during late pregnancy followed by cesarean delivery for genital lesions at delivery in women with recurrent genital herpes requires 1818 women to follow this strategy to prevent one neonatal infection and 7.4 women to take acyclovir to prevent one outbreak of genital herpes at delivery, at a cost (above no intervention) of over $493,000 per neonatal infection prevented, $1.1 million per neonatal death or disability prevented, and $1444 per maternal outbreak prevented. Cesarean delivery for genital herpes lesions requires 386 women with recurrent herpes to undergo cesareans to prevent one neonatal infection, at a cost of more than $1.3 million per neonatal infection prevented and more than $3 million per neonatal death or disability prevented. If acyclovir is given and herpes lesions still occur, the incremental cost of requiring cesarean delivery for these women over vaginal delivery with culture and follow-up of exposed infants is more than $1.4 million per neonatal infection prevented. Conclusion: Oral acyclovir prophylaxis in late pregnancy for women with recurrent genital herpes is more cost-effective than the current strategy of cesarean delivery for all women presenting with genital herpes lesions.
A "call to arms" to address epilepsy and its comorbidities.

Asato and colleagues [1] sounded a “call to arms” to all of us working with individuals with epilepsy. This appeal to undertake a course of action is an important reminder that the time is now to investigate methods by which to identify, intervene, and treat the many comorbidities (cognitive, linguistic, psychiatric, and social) associated with epilepsy. As a field, we have significant evidence to support the existence of these comorbidities, and at this point, it is essentially an indisputable fact. We also know from the general and epilepsy-specific literature that if the comorbidities are left unaddressed, they negatively impact quality of life and positive life outcomes often to a greater extent than the seizures and their treatments [2,3]. A next step must include innovative tools that are easily translated into clinical settings in order to begin to address the barriers that contribute to the underidentification of these co-occurring problems. It will be important to design methods that are clinically feasible that address the constraints related to the current pressures placed on providers as well as develop screening methods that are easy to access regardless of where the patient receives care (e.g., tertiary care center vs. community-based care). These methods will require sophisticated technology that is clinically relevant (e.g., it can be easily integrated into the electronic medical record). We can look to other fields that have learned to disseminate “free” screening measures and tools through websites and operating system applications (e.g., iPhone and Android). At Stanford University, as part of the Alzheimer's Disease Research Centers (ADRC), the Geriatric Depression Scale (GDS) continues to remain in the public domain, and its developers continue to provide easily accessible and free electronic formats to disseminate and encourage the utilization of this tool to screen for depression in this population since depression is a similarly significant comorbidity (http://www.stanford.edu/~yesavage/GDS.html). Additionally, the US military is examining ways to screen for behavioral
Finding critical sets

Abstract Several algorithms are given for finding a critical subset S determined by a binary monotonic set function ƒ over a given set U . A set S is a critical set of ƒ iff ƒ(S) = 1 and ƒ(R) = 0 for all R such that R ⋐ S , where the monotonicity of ƒ assures us that also ƒ(T) = 1 for all T satisfying S ⊆ T . Upper bounds on the worst case times for the algorithms, determined by the number of calls to the binary set function, vary downwards from 2 r [log 2 n ] function calls. Here n is the size of U and r is the size of the critical set found. We find that the conceptually easiest algorithm is not the easiest to program and also that the algorithms with better upper bounds fare more poorly in practice, based on a small sample of random trials. Although finding one critical set is easy we also show that it can quickly get very difficult to find additional critical sets, simply because it can be hard to separate known critical sets from further possible critical sets.
Fabrication of chalcogenide glass waveguide for IR evanescent wave sensors

Thin film multi-layered chalcogenide glass waveguide structures have been fabricated for evanescent wave sensing of bio toxins and other applications. Thin films of Ge containing chalcogenides have been deposited onto Si substrates, with a-GeSe2 as the cladding layer and a-GeSbSe as the core layer to form the slab waveguide. Channel waveguides have been written in the slab waveguides by appropriate light the through a mask. The photo-induced structural changes in the core layer selectively enhance refractive index at the portions of interest and thus confining the light to the channels. The waveguides have been characterized and tested for the guiding of light.
Output feedback control of parabolic PDE systems with nonlinear spatial differential operators

This article focuses on nonlinear static (direct) output feedback control of parabolic partial differential equations (PDE) systems with nonlinear spatial differential operators with application to a rapid thermal chemical vapor deposition (RTCVD) process. Initially, a detailed mathematical model is presented for the RTCVD process, which consists of a nonlinear parabolic PDE that describes the spatiotemporal evolution of the wafer temperature, coupled with a set of nonlinear ordinary differential equations (ODEs) that describes the time evolution of the chamber temperature and the concentrations of the various species. Then, a systematic methodology is presented for the synthesis of nonlinear static output feedback controllers for parabolic PDE systems with nonlinear spatial differential operators. Initially, the Karhunen-Loeve expansion is used to derive empirical eigenfunctions of the nonlinear parabolic PDE system, then the empirical eigenfunctions are used as basis functions within a Galerkin model reduction framework to derive low-order ODE systems that accurately describe the dominant dynamics of the PDE system, and finally, these ODE systems are used for the synthesis of nonlinear static output feedback controllers that guarantee stability and enforce output tracking in the closed-loop system. The proposed control method is employed to synthesize a nonlinear easy-to-implement controller for the RTCVD process that uses measurements of wafer temperature at five locations to manipulate the power of the top lamps in order to achieve uniform temperature and, thus, uniform deposition of a thin film on the wafer over the entire process cycle. The performance of the developed nonlinear output feedback controller is successfully tested through simulations and is shown to be superior to the one of a linear control scheme.
The Set1 Methyltransferase Opposes Ipl1 Aurora Kinase Functions in Chromosome Segregation

A balance in the activities of the Ipl1 Aurora kinase and the Glc7 phosphatase is essential for normal chromosome segregation in yeast. We report here that this balance is modulated by the Set1 methyltransferase. Deletion of SET1 suppresses chromosome loss in ipl1-2 cells. Conversely, combination of SET1 and GLC7 mutations is lethal. Strikingly, these effects are independent of previously defined functions for Set1 in transcription initiation and histone H3 methylation. We find that Set1 is required for methylation of conserved lysines in a kinetochore protein, Dam1. Biochemical and genetic experiments indicate that Dam1 methylation inhibits Ipl1-mediated phosphorylation of flanking serines. Our studies demonstrate that Set1 has important, unexpected functions in mitosis. Moreover, our findings suggest that antagonism between lysine methylation and serine phosphorylation is a fundamental mechanism for controlling protein function.
Dynamic coupling between coordinates in a model for biomolecular isomerization

To understand a complex reaction, it is necessary to project the dynamics of the system onto a low-dimensional subspace of physically meaningful coordinates. We recently introduced an automatic method for identifying coordinates that relate closely to stable-state commitment probabilities and successfully applied it to a model for biomolecular isomerization, the C(7eq)-->alpha(R) transition of the alanine dipeptide [A. Ma and A. R. Dinner, J. Phys. Chem. B 109, 6769 (2005)]. Here, we explore approximate means for estimating diffusion tensors for systems subject to restraints in one and two dimensions and then use the results together with an extension of Kramers theory for unimolecular reaction rates [A. Berezhkovskii and A. Szabo, J. Chem. Phys. 122, 014503 (2005)] to show explicitly that both the potential of mean force and the diffusion tensor are essential for describing the dynamics of the alanine dipeptide quantitatively. In particular, the signficance of off-diagonal elements of the diffusion tensor suggests that the coordinates of interest are coupled by the hydrodynamic-like response of the bath of remaining degrees of freedom.
Some experimental analogues of obsession

Abstract This paper is an attempt to analyse some of the features of obsessional neurosis in terms of learning theory. First, the syndrome is described and found to have three main features: brooding, strong impulses to do unacceptable things, and ritualistic, defence-substitute activities. Second, the classical psychoanalytic explanation of the etiology of obsession is reviewed. This theory locates the source of conflict in the anal stage, but fails to give a satisfactory account of the precipitating conditions and of the cause for the persistence or fixation of the neurotic responses. In the third section both the precipitating conditions and the fixation conditions are analysed in terms of factors shown to be operative in animal learning experiments.
The peripheral nociceptive actions of intravenously administered 5-HT in the rat requires dual activation of both 5-HT2 and 5-HT3 receptor subtypes.

Abstract In 16-week-old Sprague-Dawley rats lightly anesthetized with pentobarbital, 5-HT (3–96 μg/kg, i.v.;n = 6) produced distinct pseudaffective responses and a dose-dependent (slope= 17.2 ± 6.8s/log 10 dose) inhibition of the tail-flick (TF) reflex (ED 50 = 32.6 ± 9.2 μg/kg). In the same rats, a 1:1 combination of α-methyl 5-HT (a 5-HT 2 receptor selective agonist) and 2-methyl 5-HT (a 5-HT 3 receptor selective agonist) (3–192 μg/kg, i.v.), produced the same profile of pseudaffective responses and also resulted in a dose-dependent (slope= 34.0± 7.0s/log 2 dose) inhibition of the TF reflex (ED 50 = 88.4 ± 20.5 μg/kg). In contrast, administration of α-methyl 5-HT (3–192 μg/kg, i.v.) or 2-methyl 5-HT (3–192 μg/kg, i.v.) alone did not produce any pseudaffective responses or any change in TF latency from baseline. In conscious 16-week-old male Sprague-Dawley rats, administration of 5-HT (48 μg/kg, i.v.;n = 5), or a 1:1 combination of α-methyl 5-HT and 2-methyl 5-HT (total dose= 120 μg/kg, i.v.;mn = 5), resulted in a passive avoidance behavior assessed in a step-down paradigm (slopes= 139.7 ± 58.2and154.9 ± 63.9s/trial, respectively), and the same profile of distinct pseudaffective responses exhibited by the lightly pentobarbital-anesthetized rats. However, administration of either α-methyl 5-HT (96 μg/kg, i.v.;n = 4) or 2-methyl 5-HT (96 μg/kg, i.v.;n = 4), while producing significant 5-HT receptor-mediated cardiovascular responses, produced a learned behavior not different from saline (0.25 ml, i.v.;n = 6) (slopes= 7.6 ± 2.5, 6.3 ± 1.8and7.4 ± 3.6s/trial, respectively). These results are consistent with the hypothesis that the peripheral nociceptive responses to i.v. 5-HT requires dual activation of 5-HT 2 and 5-HT 3 receptor subtypes.
Surgical treatment of multiple coronary aneurysms in an elderly man

We report an unusual case involving a 70-year-old man with multiple coronary aneurysms, including a 5-cm aneurysm of the right coronary artery. The precise size was determined with magnetic resonance imaging, although the aneurysms were diagnosed initially on angiography. Multiple coronary aneurysms are rare in adults. The cause may have been atherosclerosis, syphilis, or collagen vascular disease, all of which cause weakening of the media. The patient underwent successful operation, including coronary artery bypass grafting.
Relations between facets of low- and high-dimensional group problems

One-dimensional infinite group problems have been extensively studied and have yielded strong cutting planes for mixed integer programs. Although numerical and theoretical studies suggest that group cuts can be significantly improved by considering higher-dimensional groups, there are no known facets for infinite group problems whose dimension is larger than two. In this paper, we introduce an operation that we call sequential-merge. We prove that the sequential-merge operator creates a very large family of facet-defining inequalities for high-dimensional infinite group problems using facet-defining inequalities of lower-dimensional group problems. Further, they exhibit two properties that reflect the benefits of using facets of high-dimensional group problems: they have continuous variables’ coefficients that are not dominated by those of the constituent low-dimensional cuts and they can produce cutting planes that do not belong to the first split closure of MIPs. Further, we introduce a general scheme for generating valid inequalities for lower-dimensional group problems using valid inequalities of higher-dimensional group problems. We present conditions under which this construction generates facet-defining inequalities when applied to sequential-merge inequalities. We show that this procedure yields some two-step MIR inequalities of Dash and Gunluk.
Factors influencing the formation and relative distribution of haloacetic acids and trihalomethanes in drinking water.

Various water quality and treatment characteristics were evaluated under controlled chlorination conditions to determine their influences on the formation and distribution of nine haloacetic acids and four trihalomethanes in drinking water. Raw waters were sampled from five water utilities and were coagulated with alum and fractionated with XAD-8 resin. The resulting four fractionsraw and coagulated water and the hydrophobic and hydrophilic extractswere then chlorinated at pH 6 and 8 and held at 20 °C for various contact times. The results show that increasing pH from 6 to 8 increased trihalomethane formation but decreased trihaloacetic acid formation, with little effect on dihaloacetic acid formation. More trihalomethanes were formed than haloacetic acids at pH 8, while the reverse was true at pH 6. Hydrophobic fractions always gave higher haloacetic acid and trihalomethane formation potentials than their corresponding hydrophilic fractions, but hydrophilic carbon also played an important role in disinfe...
Cardiovascular response of hypoxic myocardium to acetyl strophanthidin.

Abstract Generalized acute hypoxia (average 71 per cent of O 2 saturation) in intact dogs resulted in a slight increase in the rate of change of the left ventricular pressure (LV dpdt), left ventricular stroke work (LV SW ), and total systemic resistance. This response was similar to that reported by other workers. A positive inotropic effect of acetyl strophanthidin was demonstrated on the hypoxic myocardium, as reflected by a consistent increase in LV dpdt and LV SW , associated with no significant change in the left ventricular end-diastolic pressure. This effect was not altered by beta-adrenergic blockade. Acetyl strophanthidin, however, exerted an appreciably greater inotropism on the nonhypoxic myocardium than on the hypoxic myocardium.
Chronic Joint Disease Caused by Persistent Chikungunya Virus Infection Is Controlled by the Adaptive Immune Response

ABSTRACT Chikungunya virus (CHIKV) is a reemerging mosquito-borne pathogen that causes incapacitating disease in humans characterized by intense joint pain that can persist for weeks, months, or even years. Although there is some evidence of persistent CHIKV infection in humans suffering from chronic rheumatologic disease symptoms, little is known about chronic disease pathogenesis, and no specific therapies exist for acute or chronic CHIKV disease. To investigate mechanisms of chronic CHIKV-induced disease, we utilized a mouse model and defined the duration of CHIKV infection in tissues and the associated histopathological changes. Although CHIKV RNA was readily detectable in a variety of tissues very early after infection, CHIKV RNA persisted specifically in joint-associated tissues for at least 16 weeks. Inoculation of Rag1 −/− mice, which lack T and B cells, resulted in higher viral levels in a variety of tissues, suggesting that adaptive immunity controls the tissue specificity and persistence of CHIKV infection. The presence of CHIKV RNA in tissues of wild-type and Rag1 −/− mice was associated with histopathological evidence of synovitis, arthritis, and tendonitis; thus, CHIKV-induced persistent arthritis is not mediated primarily by adaptive immune responses. Finally, we show that prophylactic administration of CHIKV-specific monoclonal antibodies prevented the establishment of CHIKV persistence, whereas therapeutic administration had tissue-specific efficacy. These findings suggest that chronic musculoskeletal tissue pathology is caused by persistent CHIKV infection and controlled by adaptive immune responses. Our results have significant implications for the development of strategies to mitigate the disease burden associated with CHIKV infection in humans.
Electrokinetic measurement of hydrodynamic properties of grafted polymer layers on liposome surfaces

Abstract Liposomes decorated with covalently-attached neutral polymers such as poly(ethylene glycol) (PEG) are pharmaceutically useful as drug delivery vehicles due to their low immunogenicity. Protection of the liposome surface from immune-system recognition requires the end-grafting of sufficiently long PEG polymers at sufficiently high densities. The hydrodynamic properties of the surface polymer layer can be studied by electrophoretic measurement of polymer-induced hydrodynamic drag. The apparent zeta potential, calculated from the mobility by use of the Smoluchowski equation, gives the location of an apparent shear surface, assuming an electrostatic-potential profile that can be calculated from the Poisson–Boltzmann equation. The shear-surface location is a measure of the polymer-layer hydrodynamic thickness. Since PEG is neutral, the polymer-layer thickness is not expected to depend significantly on ionic strength. Electrophoretic mobilities were measured for phosphatidylglycerol:phosphatidylcholine (1:9 mol:mol) and PEG-phosphatidylethanolamine:phosphatidylcholine (1:9 mol:mol) multilamellar liposomes, with PEG ranging from 350 to 5000 Da in NaCl ranging from 0.5 to 100 mM. The apparent coat thicknesses were found to be strongly ionic-strength dependent. In a simple model, the one-dimensional Navier–Stokes equation is solved analytically in the Debye–Huckel approximation assuming a rectangular polymer-segment density profile and Stokes friction in the polymer layer. It is shown that the Smoluchowski treatment underestimates the true hydrodynamic coat thickness but approaches the correct value for low ionic strength and/or high friction in the polymer layer. The model accounts for the observed ionic-strength effects and provides a formula for extracting correct hydrodynamic thicknesses and effective frictional coefficients from the data. Fitted hydrodynamic thicknesses for the present liposomes are: 2000 PEG, 45±1 A; 3000 PEG, 73±3 A; 5000 PEG, 132±5 A. These values vary linearly with the polymer index, consistent with scaling theory for polymer brushes. The fitted polymer-layer frictional shielding lengths scale with the hydrodynamic thicknesses. Valid electrophoretic determinations of hydrodynamic thicknesses of neutral polymer coats are shown to require Debye screening lengths significantly longer than the coat extensions.
Selective Deficit of One Language in a Bilingual Patient Following Surgery in the Left Perisylvian Area

We report on a right-handed bilingual patient with a left perisylvian arteriovenous malformation that caused a mild naming deficit evident only on formal language testing in both languages. Sodium amytal injected in the left carotid artery (Wada test) before surgery resulted in speech arrest for both languages. Following surgery for removal of the lesion she developed additional deficits in her native language without alteration in her second language. Selective impairment in one language after surgery demonstrates that each language has different anatomical representation within the perisylvian dominant area.
Robotic and laparoscopic total mesorectal excision for rectal cancer: a case-matched study.

Robotic total mesorectal excision (RTME), a novel approach for the treatment of rectal cancer, has been shown in previous studies to be safe and effective. However, the results of this approach compared with laparoscopic total mesorectal excision (LTME) have not been reported in terms of clinical outcome and oncologic data. This study compared early outcomes for rectal cancer between two groups. Between April 2003 and March 2009, 82 patients from a prospectively maintained database were enrolled in a case-matched study. The patients were matched for gender, age, body mass index (BMI), and type of operative procedure. Neoadjuvant chemoradiotherapy was performed for 33 RTME patients (80.5%) and 18 LTME patients (43.9%) (p = 0.001). The mean operative time was 296 min for RTME and 315 min for LTME (p = 0.357). The number of conversions were 3 (7.3%) for RTME and 9 (22%) for LTME (p = 0.12). The anastomotic leak rate after surgery did not differ between RTME (n = 3, 8.6%) and LTME (n = 1, 2.9%) (p = 0.62). The mean number of harvested lymph nodes was 13.1 with RTME and 16.2 with LTME (p = 0.07), and negative distal resection margins (DRMs) were noted in all surgical specimens. Positive circumferential resections (CRMs) were identified in 2.4% of the RTME cases and 4.9% of the LTME cases. No difference was noted in lengths of the DRMs, times until a liquid diet, or postoperative hospital stays. The total hospitalization costs were higher in the RTME group, although the difference did not reach statistical significance. There was no operative mortality or port-site recurrence in either group. For rectal cancer, RTME may be as feasible and safe as LTME in terms of technical and oncologic issues. Further prospective randomized trials are necessary for conclusions to be drawn concerning definite oncologic outcomes of robotic procedures for rectal cancer.
The Structure of Two Anhydrous Polymorphs of Caffeine from Single-Crystal Diffraction and Ultrahigh-Field Solid-State 13C NMR Spectroscopy

In this work, we examine two anhydrous polymorphs of caffeine, as well as the monohydrate, by high-field (21 T) NMR spectroscopy, and since suitable single crystals of the anhydrous forms could be obtained, the crystal structures were also determined. At high field, the 13C NMR spectra are simplified considerably over those obtained at low field as the effect of the 14N nuclear quadrupoles on the 13C resonances becomes minimal. The spectra of the two anhydrous polymorphs provide information about the number of distinct caffeine sites and indicate structural disorder. The NMR observations are consistent with single-crystal X-ray diffraction, which shows that the structures are indeed complicated by disorder. Furthermore, the space groups obtained previously from powder diffraction were, in fact, incorrect, R3c rather than R3c for the low-temperature polymorph and C2/c rather than Cc for the high-temperature polymorph. As a result, the structures are different from those proposed on the basis of modeling c...
Regulatory and Signaling Properties of the Vav Family

X.R.B. is a Sinsheimer Scholar for Cancer Research whose own work is supported by the National Cancer Institute (CA7373501), the Baldwin Foundation for Breast Cancer Research, and the Association for International Cancer Research.
The efficacy of early ERCP in pediatric pancreatic trauma

Recognition of pancreatic injuries is frequently delayed, and optimal treatment is often controversial. The use of endoscopic retrograde cholangiopancreatography (ERCP) has allowed accurate delineation of pancreatic ductal injuries; however, the small size of children and the concern with inducing pancreatitis and/or lesser sac contamination have limited its use in children. In 1988, the authors began using ERCP for selected pancreatic injuries. This report describes their experience with this technique and examines the role of ERCP in pediatric pancreatic injuries. Six children with pancreatic transections resulting from blunt trauma were treated between 1988 and 1993. The age range was 2 1/2 to 8 years, and the weight range was 13.6 to 27.9 kg. The average period from injury to referral to the hospital was 14 days (range, 2 to 30 days). All six children presented with chemical evidence of pancreatitis and had an initial computed tomography (CT) scan; five scans were interpreted as being normal. Five of the six patients had subsequent CT scans, which showed lesser-sac fluid collection. Three patients were treated with drainage (2 percutaneous, 1 open [outside hospital]), and when this failed, ERCP was performed, at 13.6 days (average) after presentation. These three patients underwent ERCP relatively early in the course (an average of 3 days after presentation). All six children had major ductal transections documented through ERCP. After ERCP, the serum amylase level remained elevated in three, increased in one, and normal in one. (It was not measured in one of the recent cases taken for immediate operation.)(ABSTRACT TRUNCATED AT 250 WORDS)
Detection and quantitation by competitive PCR of an age-associated increase in a 4.8-kb deletion in rat mitochondrial DNA

Recent studies on human tissues have shown that the quantity of partially deleted mitochondrial DNA (mtDNA) increases with age. In this study, mtDNAs from the livers of young adult and old Wistar rats were analyzed by PCR. Evidence for partially deleted mtDNAs was found, with a 4834-bp deletion present in all animals and most easily detected in samples from senescent rats. The deletion breakpoint occurs at a 16-bp direct repeat present in the cytochrome oxidase I and ATPase 6 genes. This deletion in rats is similar in size and location to the 5.0-kb deletion observed in human mtDNA. The proportion of rat mtDNA with this 4.8-kb deletion was quantitated by a competitive PCR assay. The ratio of partially deleted mtDNA/total mtDNA in liver mtDNA from individual 6 month old rats ranged from 5 x 10(-6) to 3 x 10(-5), while the ratio in 24 month old rats ranged from 8 x 10(-4) to 5 x 10(-3), with a mean 100-fold increase with age. These increases are in the range observed for human mtDNA during aging. Thus senescent rats can be used as a model to study this type of mitochondrial DNA damage in aging. The method and reagents described should prove useful in studies of the mechanism(s) underlying deletions, their significance to the aging process, and testing of various compounds or interventions for their ability to slow the process.
Magnetic resonance imaging of the brain of normal neonatal foals.

Magnetic resonance imaging (MRI) was performed on gthe brain of 5 normal, anesthetized, neonatal (age 3-to-6 days) Quarter Horse foals. The objectives of the study were to develop a technique for imaging the brain of neonatal foals, and to ascertain their normal brain anatomy. Interavenous propofol was administered for induction and maintenance of general anesthesia. Using spin echo MR techniques, T1 weighted sagittal and transverse views, and spin density and T2 weighted transverse views were successfully made of each foal. MR images provided excellent visualization of many anatomic struictures of the brain and head. MRI of the bgrain is feasible for selected neonantal equine patients.
Selection for Higher Fitness in Populations of Drosophila pseudoobscura

Four laboratory populations, each consisting of flies homozygous for a wild second chromosome, were maintained in population cages. Three of them were initially characterized by low fecundity of the females; the fourth was a control. After 15 months, in all three populations with low fecundity this character was much improved; two of them, have reached the control level. The changes observed were presumably due to mutation and selection under highly competitive conditions.
Technology detail in a multisector CGE model: Transport under climate policy

A set of three analytical models is used to study the imbedding of specific transport technologies within a multisector, multiregion evaluation of constraints on greenhouse emissions. The key parameters of a computable general equilibrium (CGE) model are set to mimic the behavior of a model of modal splits and a market allocation (MARKAL) model of household and industry transport activities. In simulation mode, the CGE model provides key economic data to an analysis of the details of transport technology under policy restraint. Results focus on the penetration of new automobile technologies into the vehicle market.
P80 form of the human tumor necrosis factor receptor is involved in DNA fragmentation

Two different types of TNF receptors with molecular masses of 60 kDa (p60) and 80 kDa (p80) have been identified. TNF is known to cause DNA fragmentation in certain tumor cell lines but the role of p60 and p80 in this action is not understood. In the present study, we examined the role of these receptors in TNF-induced DNA fragmentation. Treatment of U-937 cells with phorbol ester caused downregulation of both types of TNF receptors and this was accompanied by disappearance of the TNF-induced DNA fragmentation. The removal of phorbol ester led to two time-dependent events: (1) the rapid regeneration of the p80 form but not the p60 form of the TNF receptor; and (2) the reappearance of TNF-induced DNA fragmentation. These results suggest that the p80 receptor could mediate the TNF-induced DNA fragmentation.
Is it cerebral or renal salt wasting

Cerebral salt-wasting (CSW), or renal salt-wasting (RSW), has evolved from a misrepresentation of the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) to acceptance as a distinct entity. Challenges still confront us as we attempt to differentiate RSW from SIADH, ascertain the prevalence of RSW, and address reports of RSW occurring without cerebral disease. RSW is redefined as 'extracellular volume depletion due to a renal sodium transport abnormality with or without high urinary sodium concentration, presence of hyponatremia or cerebral disease with normal adrenal and thyroid function.' Our inability to differentiate RSW from SIADH lies in the clinical and laboratory similarities between the two syndromes and the difficulty of accurate assessment of extracellular volume. Radioisotopic determinations of extracellular volume in neurosurgical patients reveal renal that RSW is more common than SIADH. We review the persistence of hypouricemia and increased fractional excretion of urate in RSW as compared to correction of both in SIADH, the appropriateness of ADH secretion in RSW, and the importance of differentiating renal RSW from SIADH because of disparate treatment goals: fluid repletion in RSW and fluid restriction in SIADH. Patients with RSW are being incorrectly treated by fluid restriction, with clinical consequences. We conclude that RSW is common and occurs without cerebral disease, and propose changing CSW to RSW.
Consequences of magnetization transfer on the determination of solution structures of proteins

Abstract The complete two-dimensional nuclear Overhauser enhancement (NOESY) spectra of several proteins were theoretically simulated to analyze the effect that spin diffusion has on the cross-peak intensity-interproton distance relationship as a function of rotational time τ and mixing time tm. The NOESY cross-peak intensities were calculated by solving the generalized Bloch equations from the crystal coordinates of basic pancreatic trypsin inhibitor, cytochrome b562, domain 1 of phage lysozyme, and human deoxy hemoglobin (MW 6500, 11,459, 18,625, and 64,450, respectively). It was found that correlations between cross-peak intensity and internuclear distance, useful for obtaining solution structure of proteins from nuclear magnetic resonance data, can be defined for cross peaks observed at tm = 100 ms, for rotational correlation times τ
Schwann cell ATP-mediated calcium increases in vitro and in situ are dependent on contact with neurons.

Schwann cells freshly isolated from the sciatic nerves of neonatal rats respond to exogenously applied ATP with a rapid increase in cytosolic calcium. This increase in [Ca2+]i is mediated by a P2Y-purinergic pathway (Lyons et al.: J. Neurochem. 63:552–560, 1994) and was measured using the calcium indicator dye, fura-2/AM, and a video-enhanced calcium imaging system. The ability to respond to ATP with increases in intracellular calcium is lost over a period of several days in culture; this loss can be prevented or reversed by application of cAMP analogs in a defined medium. We now demonstrate that the direct contact of Schwann cells with neurons also induces and stabilizes this ATP responsiveness. The induction of ATP responsiveness was observed among all Schwann cells contacting neurites, including those forming myelin, and regardless of whether the source of neurons was dorsal root ganglion neurons or superior cervical ganglion neurons. Approximately 85% of Schwann cells responded to ATP over the time studied (72 d in coculture). Addition of axolemma to Schwann cell cultures did not induce ATP responsiveness. We also examined the ATP responsiveness of Schwann cells in situ (excised nerves) using laser-scanning confocal microscopy and the calcium indicator dye, fluo-3/AM. Schwann cells in intact sciatic nerve segments isolated from neonatal and 16–day-old rats exhibited ATP-mediated [Ca2+]i increases. We conclude that neuronal contact is necessary for the expression of the ATP-mediated calcium responses in Schwann cells and that these responses are independent of myelin formation or maintenance. Copy 1995 Wiley-Liss, Inc.
Characterization of Specific Nucleotide Substitutions in DtxR-Specific Operators of Corynebacterium diphtheriae That Dramatically Affect DtxR Binding, Operator Function, and Promoter Strength

The diphtheria toxin repressor (DtxR) of Corynebacterium diphtheriae uses Fe(2+) as a corepressor. Holo-DtxR inhibits transcription from the iron-regulated promoters (IRPs) designated IRP1 through IRP5 as well as from the promoters for the tox and hmuO genes. DtxR binds to 19-bp operators with the consensus sequence 5'-TTAGGTTAGCCTAACCTAA-3', a perfect 9-bp palindrome interrupted by a single C. G base pair. Among the seven known DtxR-specific operators, IRP3 exhibits the weakest binding to DtxR. The message (sense) strand of the IRP3 operator (5'-TTAGGTGAGACGCACCCAT-3' [nonconsensus nucleotides underlined]) overlaps by 2 nucleotides at its 5' end with the putative -10 sequence of the IRP3 promoter. The underlined C at position +7 from the center of the IRP3 operator [C(+7)] is unique, because T is conserved at that position in other DtxR-specific operators. The present study examined the effects of nucleotide substitutions at position +7 or -7 in the IRP3 operator. In gel mobility shift assays, only the change of C(+7) to the consensus nucleotide T caused a dramatic increase in the binding of DtxR, whereas other nucleotide substitutions for C(+7) or replacements for A(-7) had only small positive or negative effects on DtxR binding. All substitutions for C(+7) or A(-7) except for A(-7)C dramatically decreased IRP3 promoter strength. In contrast, the A(-7)C variant caused increased promoter strength at the cost of nearly eliminating repressibility by DtxR. The message (sense) strand of the IRP1 operator (5'-TTAGGTTAGCCAAACCTTT-3') includes the -35 region of the IRP3 promoter. A T(+7)C variant of the IRP1 operator was also constructed, and it was shown to exhibit decreased binding to DtxR, decreased repressibility by DtxR, and increased promoter strength. The nucleotides at positions +7 and -7 in DtxR-specific operators are therefore important determinants of DtxR binding and repressibility of transcription by DtxR, and they also have significant effects on promoter activity for IRP3 and IRP1.
The super-information age of immunoglobulin genetics.

I f the information age arose with the popularization of the personal computer, then the emergence of super-powered versions of these machines completely integrated into our lives and into the superstructure of society via the Internet has led us into the super-information age. Information is
Measuring feeding rates of pelagic herbivores: analysis of experimental design and methods

We have re-evaluated the experimental methods and statistical procedures used to determine the relationship between feeding rates of pelagic herbivores and food concentration. Analysis of our own experiments, on Calanus pacificus feeding on Gyrodinium resplendens, and of other published research on this subject suggests the need for improvements in experimental design and methodology. We show that the use of “mean concentration” is statistically erroneous. First, it produces an artificial increase in the degrees of freedom that may result in the acceptance of nonsignificant regression lines. Second, it negates the value of replication, which is required to estimate sources of error. We present an example of how replication may be used to improve control over sources of error. Furthermore, we recommend the use of initial concentration rather than mean concentration. Finally, we introduce alternative methods to determine clearance and ingestion rates that enable the investigator to use replication and thus to estimate experimental errors.