cssi/SciSciGPT-SciSciNet huggingface dataset:
Management of infected shoulder arthroplasty: a comparison of treatment strategies.

Background The study purpose was to determine whether 2-stage revision procedures result in superior outcomes and whether reverse shoulder arthroplasty produced superior outcomes to hemiarthroplasty or anatomic total shoulder arthroplasty at the time of reimplantation. Methods Our prospectively collected database was retrospectively reviewed for all surgically treated infected shoulder arthroplasties between 2006 and 2014. We included 47 patients in this study: 27 underwent a 2-stage revision, and 20 were treated with an antibiotic spacer as definitive treatment. Preoperative laboratory results, intraoperative cultures and pathology findings, recurrence of infection, complications, and outcome measures were compared between treatment groups. Results A recurrent infection developed in 3 patients in the antibiotic spacer group and 2 patients in the 2-stage revision group ( P = .25). A total of 20 procedure-related complications and 11 medical complications occurred between the 2 groups; however, there was no statistically significant difference between groups. The 2-stage group had statistically significantly better Constant scores (58.1 vs. 33.3, P = .04) and elevation (94.4° vs. 48.6°, P = .02) than the antibiotic spacer group. Subanalysis of the 2-stage revision group showed that reverse total shoulder arthroplasties had statistically superior Shoulder Pain and Disability Index, Simple Shoulder Test, American Shoulder and Elbow Surgeons, University of California at Los Angeles, and Constant scores; elevation; and abduction compared with hemiarthroplasties or anatomic total shoulder arthroplasties. Conclusion Two-stage revision procedures and use of an antibiotic spacer for definitive management of periprosthetic shoulder infections appear to be similar and effective in eradicating infections. Two-stage revisions using a reverse total shoulder arthroplasty at the time of reimplantation generate superior range of motion and functional outcome scores.
Rolling classical scalar field in a linear potential coupled to a quantum field

We study the dynamics of a classical scalar field that rolls down a linear potential as it interacts bi-quadratically with a quantum field. We explicitly solve the dynamical problem by using the classical-quantum correspondence (CQC). Rolling solutions on the effective potential are shown to compare very poorly with the full solution. Spatially homogeneous initial conditions maintain their homogeneity and small inhomogeneities in the initial conditions do not grow.
A generic imperative language for polynomial time.

The ramification method in Implicit Computational Complexity has been associated with functional programming, but adapting it to generic imperative programming is highly desirable, given the wider algorithmic applicability of imperative programming. We introduce a new approach to ramification which, among other benefits, adapts readily to fully general imperative programming. The novelty is in ramifying finite second-order objects, namely finite structures, rather than ramifying elements of free algebras. In so doing we bridge between Implicit Complexity's type theoretic characterizations of feasibility, and the data-flow approach of Static Analysis.
Adsorption, intercalation, diffusion, and adhesion of Cu at the 2H−MoS2 (0001) surface from first-principles calculations

This paper presents density-functional-theory calculations that predict an intercalation of single Cu atoms into the van der Waals (vdW) gap below 2H-MoS2 (0001) surface that is strongly favored over adsorption on top of surface. Moreover, the calculations show that the system with adsorbed Cu is magnetic, but the system can become nonmagnetic after the intercalation.
Alexithymia, state-emotion dysregulation, and eating disorder symptoms: A mediation model

There were three objectives in this study. The first was to investigate if deficits in understanding and identifying emotions (i.e., alexithymia) would lead to further difficulties with emotion reg...
Field pilot study of porous asphalt pavement reinforced by cured carbon fibre composite materials (CCFCMs)

The use of a reinforcing fibre in porous asphalt (PA) is a common practice to improve PA’s homogeneity and durability. This study developed a new type of fibre-shaped reinforcement element from cur...
Cross-border COVID-19 spread amidst malaria re-emergence in Venezuela: a human rights analysis.

Since 2016 Venezuela has seen a collapse in its economy and public health infrastructure resulting in a humanitarian crisis and massive outward migration. With the emergence of the novel coronavirus SARS-CoV-2 at the end of 2019, the public health emergency within its borders and in neighboring countries has become more severe and as increasing numbers of Venezuelans migrants return home or get stuck along migratory routes, new risks are emerging in the region. Despite clear state obligations to respect, protect and fulfil the rights to health and related economic, social, civil and political rights of its population, in Venezuela, co-occurring malaria and COVID-19 epidemics are propelled by a lack of public investment in health, weak governance, and violations of human rights, especially for certain underserved populations like indigenous groups. COVID-19 has put increased pressure on Venezuelan and regional actors and healthcare systems, as well as international public health agencies, to deal with a domestic and regional public health emergency. International aid and cooperation for Venezuela to deal with the re-emergence of malaria and the COVID-19 spread, including lifting US-enforced economic sanctions that limit Venezuela’s capacity to deal with this crisis, is critical to protecting rights and health in the country and region.
How Often Should Reputation Mechanisms Update a Trader's Reputation Profile?

Reputation mechanisms have become an important component of electronic markets, helping to build trust and elicit cooperation among loosely connected and geographically dispersed economic agents. Understanding the impact of different reputation mechanism design parameters on the resulting market efficiency has, thus, emerged as a question of theoretical and practical interest. Along these lines, this note studies the impact of the frequency of reputation profile updates on cooperation and efficiency. The principal finding is that, in trading settings with pure moral hazard and noisy ratings, if the per-period profit margin of cooperating sellers is sufficiently high, a mechanism that does not publish every single rating it receives but rather, only updates a trader's public reputation profile every k transactions with a summary statistic of a trader's most recent k ratings, can induce higher average levels of cooperation and market efficiency than a mechanism that publishes all ratings as soon as they are posted. The note derives expressions for calculating the optimal profile updating interval k, discusses the implications of this finding for existing systems, such as eBay, and proposes alternative reputation mechanism architectures that attain higher maximum efficiency than the, currently popular, reputation mechanisms that publish summaries of a trader's recent ratings.
Incidence of insomnia and obstructive sleep apnea in active duty United States military service members.

STUDY OBJECTIVES Epidemiologic studies of obstructive sleep apnea (OSA) and insomnia in the U.S. military are limited. The primary aim of this study was to report and compare OSA and insomnia diagnoses in active duty the United States military service members. METHOD Data and service branch densities used to derive the expected rates of diagnoses on insomnia and OSA were drawn from the Defense Medical Epidemiology Database. Single sample chi-square goodness of fit tests and independent samples t-tests were conducted to address the aims of the study. RESULTS Between 2005 and 2019, incidence rates of OSA and insomnia increased from 11 to 333 and 6 to 272 (per 10,000), respectively. Service members in the Air Force, Navy, and Marines were diagnosed with insomnia and OSA below expected rates, while those in the Army had higher than expected rates (p < .001). Female service members were underdiagnosed in both disorders (p < .001). Comparison of diagnoses following the transition from ICD 9 to 10 codes revealed significant differences in the amounts of OSA diagnoses only (p < .05). CONCLUSION Since 2005, incidence rates of OSA and insomnia have markedly increased across all branches of the U.S. military. Despite similar requirements for overall physical and mental health and resilience, service members in the Army had higher rates of insomnia and OSA. This unexpected finding may relate to inherent differences in the branches of the military or the role of the Army in combat operations. Future studies utilizing military-specific data and directed interventions are required to reverse this negative trend.
“The green peach aphid, Myzus persicae, transcriptome in response to a circulative, nonpropagative polerovirus, Potato leafroll virus”

Abstract Viruses in the Luteoviridae family, such as Potato leafroll virus (PLRV), are transmitted by aphids in a circulative and nonpropagative mode. This means the virions enter the aphid body through the gut when they feed from infected plants and then the virions circulate through the hemolymph to enter the salivary glands before being released into the saliva. Although these viruses do not replicate in their insect vectors, previous studies have demonstrated viruliferous aphid behavior is altered and the obligate symbiont of aphids, Buchnera aphidocola, may be involved in transmission. Here we provide the transcriptome of green peach aphids (Myzus persicae) carrying PLRV and virus-free control aphids using Illumina sequencing. Over 150 million paired-end reads were obtained through Illumina sequencing, with an average of 19 million reads per library. The comparative analysis identified 134 differentially expressed genes (DEGs) between the M. persicae transcriptomes, including 64 and 70 genes that were down- and up-regulated in aphids carrying PLRV, respectively. Using functional classification in the GO databases, 80 of the DEGs were assigned to 391 functional subcategories at category level 2. The most highly up-regulated genes in aphids carrying PLRV were cytochrome p450s, genes related to cuticle production, and genes related to development, while genes related to histone and histone modification were the most down-regulated. PLRV aphids had reduced Buchnera titer and lower abundance of several Buchnera transcripts related to stress responses and metabolism. These results suggest carrying PLRV may reduce both aphid and Buchnera genes in response to stress. This work provides valuable basis for further investigation into the complicated mechanisms of circulative and nonpropogative transmission.
Residential exposure to carbamate, organophosphate, and pyrethroid insecticides in house dust and risk of childhood acute lymphoblastic leukemia.

Abstract Background Self-reported residential use of pesticides has consistently been associated with increased risk of childhood leukemia. However, these studies were limited in their ability to identify specific insecticide active ingredients that were associated with risk. Objective We used household carpet dust measurements of 20 insecticides (two carbamate, 10 organophosphate, two organochlorine, and six pyrethroid) as indicators of exposure and evaluated associations with the risk of childhood acute lymphoblastic leukemia (ALL). Methods We conducted a population-based case-control study of 252 ALL cases diagnosed from 1999 to 2007 and 306 birth certificate controls from 35 counties in Central and Northern California. Carpet dust was collected at a second interview (2001–2007) for cases who had not moved since diagnosis (comparable reference date for controls) using a specialized vacuum cleaner in the room where the child spent most of their time or from the household vacuum. Insecticides were categorized as detected (yes/no), or as tertiles or quartiles of their distributions among controls. We calculated odds ratios (OR) and 95% confidence intervals (CI) using unconditional logistic regression adjusting for demographic characteristics, interview year, and season of dust collection. Results Permethrin, chlorpyrifos, diazinon, and carbaryl were the most frequently detected insecticide active ingredients. When we compared the highest quartile to the lowest or to non-detections, there was no association with ALL for permethrin (OR Q4 vs. Q1 = 0.81; 95% CI 0.50–1.31), carbaryl (OR Q4 vs. non-detects = 0.61, 95% CI 0.34–1.08) or chlorpyrifos (OR Q4 vs. Q1 = 0.60; 95% CI 0.36–1.00). The highest quartile of diazinon concentration was inversely associated with risk in the single pesticide model but without a monotonic exposure-response (p-trend = 0.14). After adjusting for other common insecticides, the OR was not significant (OR Q4 vs. Q1 = 0.58; 95% CI 0.33–1.05). None of the other insecticides were associated with risk. Conclusion Our results should be interpreted within the limitations of the case-control study design including the use of a single post-diagnosis dust sample and restriction to residentially stable participants, which may have resulted in selection bias. Although difficult to implement, additional studies with assessment of exposure to insecticide active and non-active ingredients are necessary to elucidate the role of these common exposures in childhood leukemia risk.
A semantically driven self-supervised algorithm for detecting anomalies in image sets

Abstract Humans can readily detect when an image does not belong in a set by comparing semantic information between images to derive meaning and relationships from the colors, shapes, sizes, locations, and textures within them. Current self-supervised anomaly detection algorithms in computer vision do not possess this ability. Most algorithms learn to detect anomalies through a training objective that only optimizes for machine-level features and do not evaluate semantic features. To fill this gap, we propose a novel self-supervised algorithm that detects anomalies by learning and modeling semantic information within a set of images. This is accomplished by first training our algorithm to be sensitive or invariant to targeted semantic information, and then modeling the semantic relationships learned so that we can detect anomalies by measuring how far images deviate from the model. Experimenting with our algorithm, we show that different datasets can have different semantic sensitivities, those sensitivities can fluctuate between and within sets depending on different aspects of the images, and directly targeting those sensitivities can improve anomaly detection performance. Using our algorithm, we were able to achieve a AUROC of 0.7146 on the CIFAR-10 dataset, which is an improvement of 0.0741 over another current leading self-supervised anomaly detection algorithm.
SU-E-J-189: Determination of Markerless Lung Tumor Position in Real Time: A Feasibility Study Using a Novel Tomo-Cinegraphy Imaging

Purpose: A Tomo-Cinegraphy (TC) is a method to generate a series of temporal tomographic images from projection images of the on-board imager (OBI) while gantry is moving. It is to test if this technique is useful to determine a lung tumor position during treatments. Methods: Tomographic image via background subtraction, TIBS uses a priori anatomical information from a previous CT scan to isolate a SOI from a planar kV image by factoring out the attenuations by tissues outside the SOI (background). This idea was extended to a TC, which enables to generate tomographic images of same geometry from the projection of different gantry angles and different breathing phases. Projection images of a lung patient for CBCT acquisition are used to generate TC images. A region of interest (ROI) is selected around a tumor adding 2cm margins. Center of mass (COM) of the ROI is traced to determine tumor position for every projection images. Results: Tumor is visible in the TC images while the OBI projections are not. The coordinates of the COMs represent the temporal tumor positions. While, it is not possible to trace the tumor motion using the projection images. A source of time delay is the time tomore » acquire projection images, which is always less than a second. Conclusion: TC allows tracking the tumor positions without fiducial markers in real time for some lung patients, if the projection images are acquired during treatments. Partially supported by NIH R01CA133539.« less
Hemangiomas: Clinical Picture

Infantile hemangiomas or hemangiomas of infancy are the most common benign cutaneous tumors of infancy. The pathogenesis of infantile hemangiomas remains unclear. They are composed by masses of capillaries lined by endothelial cells that have a unique vascular phenotype demonstrated by the erythrocyte-type glucose transporter protein staining (GLUT-1). Infantile hemangiomas present shortly after birth most often as well-demarcated, flat, and erythematous red patches. They follow a predictable course with three distinct phases: proliferation (8–18 months), involuting phase (1–7 years), and involuted. They are classified as superficial, deep, or combined.
Kinetics and mechanisms of intermolecular ligand exchange

Abstract The kinetics and mechanisms of intermolecular ligand exchange of acetylacetonate (acac) groups between “bulk” free acetylacetone (enol form) and R 2 Sn-(acac) 2 (R  CH 3 or Ph) complexes have been re-investigated in chloroform- d (R  CH3) and chlorobenzene (R Ph) solutions by proton magnetic resonance spectroscopy using the total lineshape analysis in the temperature range: 12.7–37.0°C (R  CH 3 ;acac CHregion),−1.4 to 19.6°C (R  CH 3 ; acac CH 3 region), and 25.9–48.0°C (R Ph; acac CHregion). The activation energies and entropies of activation are: for R  CH 3 , 7.2 ± 0.7 kcal/mol and −30 ± 3 eu (acac CH 3 ), and 6.3 ± 0.6 kcal/mol and −32 ± 2 eu (acac CH); for R  Ph 8.8 ± 2.7 kcal/mol and −31 ± 9 eu (acac CH). Concentration dependence studies for both the (CH 3 ) 2 Sn(acac) 2 Hacac and Ph 2 Sn(acac) 2 Hacac systems indicate that the rate of acetylacetonate exchange is first-order in the concentration of R 2 Sn(acac) 2 and zero order in the concentration of “bulk” free ligand. The intermolecular ligand exchange phenomenon is believed to involve coordination number lowering; viz. a Sn-O bond rupture as the rate-determining step to yield a five-coordinate intermediate species with a dangling unidentate acetylacetonate ligand.
Modeling of the viscoelastic behavior of collagen gel from dynamic oscillatory shear measurements.

Background Viscoelastic materials contain a continuous spectrum of relaxation time constants that cannot be measured directly from experiments. To model the viscoelastic behavior, discrete Generalized Maxwell model is usually chosen phenomenologically from direct fitting. Objective In the present study, a theoretical framework was developed to determine the continuous spectrum of relaxation time constants, and then applied to study the dynamic rheological behavior of collagen gel using a parallel plate rheometer. Methods Frequency sweep tests were performed to determine the storage and loss modulus of collagen gel. To obtain the continuous relaxation spectrum, Tikhonov regularization method was employed to solve the Fredholm integral equations. A Finite Element Model (FEM) was created to simulate the rheological measurement with viscous material parameters obtained from both direct fitting and continuous spectrum. Results Discrete spectrum obtained by direct fitting method is not unique and highly depends on the specified fitting criteria. Continuous spectrum obtained by Tikhonov regularization effectively eliminates the possibility of getting nonunique solutions. The storage and loss modulus calculated from FEM compared well with the experimental results. Conclusions Continuous relaxation spectrum can be determined based on dynamic rheological shear measurements, and incorporated into FEM to study the behavior of viscoelastic materials.
A Review of “Teaching in the Art Museum: Interpretation and Experience”

In late 2007, I was invited to a museum education symposium by the Metropolitan Museum in New York City to celebrate the opening of their new education center. I was excited to go behind the scenes...
A 200-A, 500-Hz, triangle current-wave modulator and magnet used for particle beam rastering

This paper describes a simple 2D beam-rastering system to uniformly spread a 100-mA 6.7-MeV CW proton beam over a 50-cm by 50-cm beam stop. The basic circuit uses a 20-mF capacitor bank, a IGBT (insulated gate bipolar transistor) full-wave inverter, and a 1-mH ferrite dipole magnet to produce a /spl plusmn/500-Gauss peak triangular-waveform deflection field at 500 Hz. A DC input voltage of 200 volts at 2.6 amps (520 watts) produces a 160-ampere peak-to-peak triangular current waveform in the ferrite magnet at 500 Hz. For dual-axis rastering, two ferrite dipoles are used, one at 500 Hz, and the other at 575 Hz, to produce a uniform 2D beam distribution at the beam stop. The paper will discuss the IGBT modulator and ferrite deflector in detail, including current and voltage waveforms, and the ferrite magnet B-dot (dB/dt) signal.
Our Shared Journey Toward Sustainability

This final chapter discusses how the constitutive and pragmatic power of communication allows employees to exert agency and organizations and interorganizational collaborations to change societal-level Discourses. SMART messaging is discussed. Suggestions are provided to researchers and practitioners on next steps each might take. Remaining wisdom drawn from the interview transcripts is shared. Scholarly literature discussing wisdom and spirituality is reviewed. Both must be encouraged within and between our organizations if we are to move forward in creating and expanding truly meaningful sustainability initiatives.
“I’m trying to figure this out. Why don’t you come up here?”: heterogeneous talk and dialogic space in a mathematics discussion

In this paper, we frame mathematics classrooms as heterogeneous spaces wherein students draw on multiple storylines based on different notions of schooling and school mathematics to both communicate mathematical ideas and position themselves and one another. We focus on a fourth grade (age range 9.4–10.8 years) mathematics classroom discussion in a racially and linguistically diverse urban school in the Southeastern US. Our results reveal that some students drew from traditional notions of school mathematics focused on evaluating right and wrong answers, while others drew on a more dialogic notion of school mathematics supported by local ground rules for making reasoning explicit, revising one’s thinking, and inviting multiple voices. The result was a heterogeneous space that both enabled and constrained possibilities for the construction of a dialogic space. We end with a discussion of the complexities of dialogic teaching in mathematics classrooms given the discipline’s narrative history.
Irrelevant prime divisors

Abstract With I ⊆ P ϵSpec R , and I a regular ideal in the Noetherian ring R , we discuss when ( u,P,It ) is a prime divisor of uR(I) in the Rees ring R(I)=R[u,It] of R with respect to I .
903-15 Expression of 92 kDa Gelatinase in Primary Atherosclerotic vs Restenotic Coronary Lesions: Evidence for Mechanical Plaque Stabilization

Rupture of atherosclerotic plaque resulting in intravascular thrombosis and myocardial infarction (MI), while a common sequelae of primary atherosclerotic lesions, is an uncommon consequence of restenosis. We hypothesize that the rarity of MI associated with restenotic lesions is a result of cellular and biochemical modifications induced by the local response to balloon injury rendering the site resistant to rupture (plaque stabilization). Clinical and angiographic features of pts presenting with symptomatic primary (n = 24) or restenotic coronary lesions (n = 12) who underwent directional atherectomy were compared. Histologic analysis and immunostaining forthe matrix degrading enzyme, 92 kDa gelatinase, were performed on each atherectomy specimen. There was no significant difference between the 2 groups regarding age, gender, incidence of diabetes, smoking, hypertension, hypercholesterolemia or previous MI. Extent and distribution of disease, vessel caliber and % stenosis were not significantly different between groups. However, 8% of primary lesions were hypercellular compared to 75% (p = 0.0001) of restenotic specimens. 92 kDa gelatinase was expressed in 79% of primary lesions vs 0% of restenotic specimens (p = 0.0001). Thrombus was identified in 54% of primary lesions vs 22% of restenotic lesions (p l 0.05). Conclusion These findings suggest that, independent of clinical or angiographic influences, balloon injury induced increased lesion cellularity and reduced expression of 92 kDa gelatinase, possibly conferring less propensity for plaque rupture and thrombosis.
Computer analysis of proteins separated by polyacrylamide gradient pore gel electrophoresis.

Abstract A method for measuring lymph-to-plasma (L/P) protein concentration ratios obtained from protein fractions separated by polyacrylamide gradient gel electrophoresis is presented. A curve-fitting technique is used to decompose lymph and plasma electropherograms containing multiple components into individual components, eliminating protein-protein overlap regions. This allows the concentration of each component in the mixture to be measured accurately, yielding more precise estimates of L/P ratios. This technique consists of three phases. (1) Individual electropherograms are constructed for proteins of various sizes by taking a weighted average of measured electropherograms obtained from the two protein standards closest in size to the protein of interest, (2) Using these generated standard curves, the multicomponent lymph and plasma curves are decomposed into the least number of equally spaced components that yield a good fit. A linear least-squares method is used to do this. Each protein fraction is multiplied by the total measured protein concentration to provide a concentration for each component. (3) Finally, L/P concentration ratios of protein fractions with visible peaks were computed by applying an averaging technique to the equally spaced protein fractions. Plots of sheep lung L/P ratio versus protein size obtained in this manner were compared to L/P ratios obtained using a method of analysis which does not correct for protein overlap. The corrected L/P ratios showed less scatter than the uncorrected curves. Lung lymph data analyzed with the correction method indicated an increased lung microvascular permeability for large proteins following endotoxin infusion, whereas the uncorrected curves were too noisy to support this concept.
Laryngeal Amyloidosis in 10 Patients

Objectives: Review the location, symptoms, treatment, and outcomes in 10 consecutive laryngeal amyloid (LA) patients. Study Design: Pre and retrospective evaluation after treatment. Methods: Analysis of visual and phonatory pathology and detailed description of surgery. Results: Amyloid on the undersurface of both true vocal cords (TVCs) was found in two cases, uni- or bilaterally submucosally in the false vocal cords (FVCs) in eight cases, extending down into the lateral TVC in four cases, or on the undersurface of the TVCs as well in one case. The chief complaint was hoarseness and not shortness of breath. The amyloid was resected with a CO 2 laser by way of microdirect laryngoscopy (MDL) on one side at a time to try to prevent anterior commissure scarring. Removal of most of the FVC improved the voice, but removal of the whole FVC to the inner thyroid perichondrium was found to be necessary to avoid recurrence from supraglottic deposits. Removal of at least 2 mm of the upper edge of a 3 to 4 mm thick submucosal deposit to the thyroarytenoid (TA) muscle along with the overlying mucosa on at least one side was necessary to improve hoarseness when amyloid was present on the undersurface of both TVCs. Partial regrowth occurred in a few months to years after partial removal. Seven patients had had one to seven prior removals. Any hard amyloid in the lateral TVC (floor of ventricle) as an inferior extension from FVC amyloid needed to be at least partially removed to avoid hoarseness from a convex vocal cord. The voice improved postoperatively in all patients. Follow-up after the first operation was 6 months to 16 years, with an average of 6.5 years. Four FVC patients required re-excision on the same side after the first operation, but none has required a third removal as of yet.
Rho-kinase inhibitors as therapeutics: from pan inhibition to isoform selectivity

The emerging critical implications of Rho/Rho-kinase (ROCK) signaling in neurodegenerative diseases, glaucoma, renoprotection, diabetes and cancer have sparked growing interest in the pharmacological potential of ROCK inhibitors beyond their current application in cardiovascular disease. This article discusses the therapeutic benefits of novel ROCK inhibitors in development, and highlights the recent advances in the current understanding of disease-dependent and isoform-specific functions of ROCK and their potential impact on future therapeutic strategies.
Hidden Markov chains, the forward-backward algorithm, and initial statistics

The objects listed in the title have proven to be useful and practical modeling tools in continuous speech recognition work and elsewhere. Nevertheless, there are natural and simple situations in which the forward-backward algorithm will be inadequate for its intended purpose of finding useful maximum likelihood estimates of the parameters of the distribution of a probabilistic function of a Markov chain (a "hidden Markov model" or "Markov source model"). We observe some difficulties that arise in the case of common (e.g., Gaussian) families of conditional distributions for the observables. These difficulties are due not to the algorithm itself, but to modeling assumptions which introduce singularities into the likelihood function. We also comment on the fact that the parameters of a hidden Markov model cannot, in general, be determined, even if the distribution of the observables is completely known. We close with remarks about some effects of these modeling and estimating difficulties on practical speech recognition, and about the role of initial statistics.
Fine structure of excitons in Cu 2 O

Three experimental observations on 1s excitons in ${\mathrm{Cu}}_{2}$O are not consistent with the picture of the exciton as a simple hydrogenic bound state: the energies of the 1s excitons deviate from the Rydberg formula, the total exciton mass exceeds the sum of the electron and hole effective masses, and the triplet-state excitons lie above the singlet. Incorporating the band structure of the material, we calculate the corrections to this simple picture arising from the fact that the exciton Bohr radius is comparable to the lattice constant. By means of a self-consistent variational calculation of the total exciton mass as well as the ground-state energy of the singlet and the triplet-state excitons, we find excellent agreement with experiment.
Sex and Centralization in a Semiprofession

Because direct empirical comparisons of the organizational participation of women and men have been lacking, attempts to incorporate gender as an explanatory variable in theories of organizational authority have had to rely on unverified sex stereotypes. This research examines contentions which have appeared repeatedly in such attempts, namely (a) that there are differences between men and women in four types of work orientation, and (b) that these differences are reflected in greater centralization of authority in predominantly female organizations. To isolate the effects of gender, semiprofessionals in ten very similar organizations were surveyed (Catholic secondary schools). Results show little difference in career commitment, and no support for stereotypes of women as less concerned with intrinsic characteristics of work and more submissive to authority than men. With or without multivariate controls, women do appear to value interpersonal relationships on the job somewhat more highly. However, facult...
Extrinsic neural innervation mediates absorption of water and electrolytes in canine proximal colon in vivo.

Abstract Introduction. Extrinsic innervation mediates a proabsorptive effect in small intestine. Our aim was to determine whether extrinsic neural input modulates similar effects in the proximal colon in vivo. Methods. Ten adult dogs underwent enteric isolation of a 50-cm proximal colon loop; five each were randomized to undergo extrinsic denervation (Ext Den) of the isolated colonic segment or to serve as neurally innervated controls. After recovery, a 38°C electrolyte solution (Na + 125 meq/L, K + 9 meq/L, Cl − 75 meq/L, HC0 − 3 65 meq/L) was infused at 4 ml/min into the segment. Effluent was collected in 30-min intervals for 2 h after achieving steady state (determined by 14 C nonabsorbable marker recovery); four studies were conducted at 1 and 12 weeks postoperatively. Net flux of H 2 0, Na + , K + , and Cl − was determined. Colon morphometry was evaluated at 0 and 14 weeks. Data are presented as x ± SEM. Unpaired t test was applied for comparisons. Results. Net absorptive flux of H 2 0 (μL/min/cm) was decreased in Ext Den vs controls at 1 week (4.40 ± 0.63 vs 7.92 ± 0.92, P = 0.03) but was not different at 12 weeks (4.70 ± 1.20 vs 5.97 ± 0.69; P > 0.05). Na + and Cl − followed the trends in H 2 0 absorption ( P ≤ 0.05). Crypt depth (μm) decreased in controls at 14 weeks vs 0 week (915 ± 20 vs 740 ± 07, P = 0.01) but remained unchanged in Ext Den. Conclusions. Loss of extrinsic neural input decreases colonic absorption. This observation suggests that extrinsic neural innervation provides net proabsorptive mechanisms for absorption of water and electrolytes in the proximal canine colon.
The role of the phosphatidyinositol-linked D1 dopamine receptor in the pharmacology of SKF83959

Abstract SKF83959, previously described as an antagonist of the D 1 dopamine receptor, has been shown to be a potent anti-parkinsonian agent. However, its mechanism of action is unknown. The present communication was designed to study the mechanism by which SKF83959 exerts its pharmacological effects. SKF83959 induced contralateral rotations in the unilateral 6-OHDA-lesioned rat model of Parkinson's disease (PD). The rotations were completely blocked by the D 1 dopamine receptor antagonist, SCH23390. The response was not affected by the serotonin receptor antagonist, mesulergine and was transiently attenuated by α 1 adrenergic or D 2 dopamine receptor antagonists, prazosin or spiperone, respectively. Injection of 0.5 and 1 mg/kg SKF83959 elicited significant elevations in IP 3 accumulation in lesioned as compared to intact striata. This effect was blocked by SCH23390 at a dose that completely obviated the rotational response to SKF83959, suggesting that activation of the PI-linked D 1 dopamine receptor and the PLC/IP 3 pathway may be the underlying mechanism for the rotational activity induced by SKF83959. The present data provide the first evidence that the PI-linked D 1 dopamine receptor plays a role in regulating motor activity in striatum and that modulation of the D 1 dopamine receptor/PLC/IP 3 pathway may be a novel target in the discovery of drugs for the treatment of Parkinson's disease.
Physical and chemical characterization of vitellogenin from the hemolymph and eggs of the tobacco hornworm, Manduca sexta.

Abstract 1. 1. Vitellogenin has been purified from mature eggs and the hemolymph of adult females of Manduca sexta by a combination of gel permeation chromatography and sodium bromide density gradient centrifugation. 2. 2. It has a molecular weight of 2.6 × 10 5 and is a glycolipoprotein containing approx 11% lipids and 3% carbohydrates. 3. 3. The carbohydrate moiety is comprised entirely of mannose and N- acetyl glucosamine. 4. 4. Two polypeptide chains are present with molecular weights of 1.8 × 10 5 and 5.0 × 10 4 . 5. 5. Partial proteolytic hydrolysis of vitellogenin resulted in the degradation of the large polypeptide but did not affect the small one, suggesting that the small polypeptide is located in the interior of the particle. 6. 6. The proteolytic hydrolysis products of the large polypeptide differed from one another by approx 12.5 × 10 3 daltons.
Scale dependence of mechanical properties of single crystals under uniform deformation

Abstract Mechanism-based discrete dislocation plasticity is used to investigate the effect of size on micro-scale crystal plasticity under nominally uniform compression. Constitutive rules are used which include a physical representation of dislocation sources and obstacles in the undeformed samples. The simulations predict a strong size dependence of the material flow stress and reproduce the main features of recent experiments. Possible operating mechanisms are identified which highlight the interplay between sample dimensions, internal stresses and the length and time scales inherent to dislocation generation and motion.
On the tensile stress-strain relation and the bauschinger effect for polycrystalline materials from taylor's model☆

Abstract A n extension of T aylor 's theoretical model has been used to investigate the behaviour of a polycrystalline material subjected to a fully plastic tensile strain first in one sense of displacement and then in the opposite sense. Some agreement with experimental results has been obtained.
FOLDING AMPHIPATHIC HELICES INTO MEMBRANES: AMPHIPHILICITY TRUMPS HYDROPHOBICITY

High amphiphilicity is a hallmark of interfacial helices in membrane proteins and membrane-active peptides, such as toxins and antimicrobial peptides. Although there is general agreement that amphiphilicity is important for membrane-interface binding, an unanswered question is its importance relative to simple hydrophobicity-driven partitioning. We have examined this fundamental question using measurements of the interfacial partitioning of a family of 17-residue amidated-acetylated peptides into both neutral and anionic lipid vesicles. Composed only of Ala, Leu, and Gln residues, the amino acid sequences of the peptides were varied to change peptide amphiphilicity without changing total hydrophobicity. We found that peptide helicity in water and interface increased linearly with hydrophobic moment, as did the favorable peptide partitioning free energy. This observation provides simple tools for designing amphipathic helical peptides. Finally, our results show that helical amphiphilicity is far more important for interfacial binding than simple hydrophobicity.
Mass fractionation of nickel isotopes in metallic cosmic spheres

Abstract The isotopic abundances of stable Ni isotopes were measured by inductively coupled plasma mass spectrometry (ICP/MS) in seven cosmic, metallic (Type I) spheres collected from the deep sea. Mass-dependent enrichments of the heavier isotopes range from 0.5–2.8% / AMU, values larger than those reported previously for Ni in any solid, extraterrestrial sample. This mass fractionation most likely reflects the high-temperature vaporization and loss from some spheres of over 90% of the Ni initially present.
Surgical creation of aortopulmonary window in selected patients with pulmonary atresia with poorly developed aortopulmonary collaterals and hypoplastic pulmonary arteries.

Abstract Objective: The morphologic characteristics of the pulmonary circulation vary widely in patients with pulmonary atresia, ventricular septal defect, and major aortopulmonary collaterals. Although we favor single-stage unifocalization and complete repair as the procedure of choice, a subgroup of patients who meet specific criteria have been treated with initial surgical creation of an aortopulmonary window. Methods: Eighteen patients who were considered unsuitable candidates for single-stage repair underwent surgical creation of an aortopulmonary window. Selection criteria included the following: (1) presence of centrally confluent true pulmonary arteries 1.0 to 2.5 mm in diameter, with a well-developed peripheral arborization pattern; (2) multiple small aortopulmonary collateral vessels, most of which communicated with the true pulmonary arterial system; and (3) the presence of marked cyanosis. Results: There were no early deaths, and the 2 late deaths were both unrelated to the procedure. Follow-up angiography (n = 17) demonstrated good growth of true pulmonary arteries in 15 of 17 cases (88%). Mean pulmonary artery diameter increased from 1.76 mm to 3.45 mm. Subsequent operations have been performed in 15 of 18 cases (83%). Intracardiac repair with or without additional unifocalization was achieved in 8 of these 15 (53%). Seven patients (47%) have undergone staged unifocalization as the next procedure; of these, 3 were able to have intracardiac repair. Thus 11 of the 15 patients who have undergone second operations (73%) have had complete intracardiac repair. Conclusions: The initial surgical creation of an aortopulmonary window in carefully selected patients can increase the size of the true pulmonary arteries, making these patients better candidates for eventual intracardiac repair. The procedure should be avoided in patients with pulmonary overcirculation, a predominance of isolated supply collaterals, or true pulmonary arteries larger than 2.5 mm in diameter, and it is not applicable without a true pulmonary artery central confluence. J Thorac Cardiovasc Surg 2002;123:1147-54
Energy metabolism and electrolytes during thiopentone meperidine anaesthesia in normal man

Energy metabolism and electrolyte values were studied in 28 volunteers during general anaesthesia without operation for periods up to 3 hours. Anaesthesia was induced and maintained with a combination of thiopentone sodium, meperidine, and succinylcholine given by intravenous injection. Ventilation was controlled and normal arterial oxygen and carbon dioxide tensions were maintained. Plasma sodium and potassium concentrations did not change but those of magnesium and inorganic phosphate decreased during anaesthesia. Plasma concentrations of total and ionized calcium, parathyroid hormone, and total protein concentration were unchanged. Blood glucose and plasma insulin concentrations increased from exogenous dextrose but those of fatty acids, ketone bodies, luteinizing hormone, and growth hormone showed no change. General anaesthesia with these nonvolatile agents produced no evidence of a stress response as reflected in energy metabolism.
COSMOS-7: Video-Oriented MPEG-7 Scheme for Modelling and Filtering of Semantic Content

MPEG-7 prescribes a format for semantic content models for multimedia to ensure interoperability across a multitude of platforms and application domains. However, the standard leaves it open as to how the models should be used and how their content should be filtered. Filtering is a technique used to retrieve only content relevant to user requirements, thereby reducing the necessary content-sifting effort of the user. This paper proposes an MPEG-7 scheme that can be deployed for semantic content modelling and filtering of digital video. The proposed scheme, COSMOS-7, produces rich and multi-faceted semantic content models and supports a content-based filtering approach that only analyses content relating directly to the preferred content requirements of the user.
Expression of Serotonin Transporter Messenger RNA in the Human Brain

: The characterization and cellular localization of human brain mRNA encoding the serotonin transporter were investigated using northern blot analysis and in situ hybridization histochemistry. In contrast to results from rodent studies, in which single hybridizing mRNAs are detected in brain and periphery, northern analysis of human midbrain raphe tissue revealed the presence of three mRNA species absent from samples prepared from sub-stantia nigra/ventral tegmental area. In situ hybridization studies revealed dense hybridization signal corresponding to serotonin transporter mRNA highly localized to neurons of the dorsal and median raphe nuclei and the caudal linear nucleus. No hybridization signal was observed in neurons of the substantia nigra or locus ceruleus. These findings demonstrate the first anatomical visualization of human brain serotonin transporter gene expression and reveal heterogeneity associated with serotonin transporter transcripts, similar to, but distinct from the pattern of expression visualized in human peripheral tissues.
Purchasing Power Parity and the Law of One Price: Evidence from Commodity Prices in Asian Countries

Almost all previous studies that have tested the law of one price or Purchasing Power Parity theory (PPP) have used either real effective exchange rates or bilateral real exchange rates which are c...
Differential regulation by fatty acids of protein histidine phosphorylation in rat pancreatic islets.

Long-chain fatty acids (e.g. arachidonic acid) have been implicated in physiological control of insulin secretion. We previously reported histidine phosphorylation of at least two islet proteins (e.g., NDP kinase and the β subunit of trimeric G-proteins), and suggested that such a signalling step may have regulatory roles in β cell signal transduction, specifically at the level of G-protein activation. Since our earlier findings also indicated potential regulation by long-chain fatty acids of islet G-proteins, we undertook the current study to verify putative regulation, by fatty acids, of protein histidine phosphorylation of NDP kinase and Gβ subunit in normal rat islets. The phosphoenzyme formation of NDP kinase was stimulated by various fatty acids in the following rank order: linoleic acid < arachidonic acid < oleic acid < palmitic acid = stearic acid = control. Furthermore, the catalytic activity of NDP kinase was stimulated by these fatty acids in the rank order of: oleic acid < arachidonic acid < linoleic acid < palmitic acid = stearic acid = control. Arachidonic acid methyl ester, an inactive analog of arachidonic acid, did not significantly affect either the phosphoenzyme formation or the catalytic activity of NDP kinase. Interestingly, arachidonic acid exerted dual effects on the histidine phosphorylation of β subunit; it significantly stimulated the phosphorylation at 33 μM beyond which it was inhibitory. Together, these findings identify additional loci (e.g., NDP kinase and Gβ subunit) at which unsaturated, but not saturated, fatty acids could exert their intracellular effects leading to exocytotic secretion of insulin (Mol Cell Biochem 266: 175–182, 2004)