cssi/SciSciGPT-SciSciNet huggingface dataset:
Disintegrin-Integrin Binding for Attachment of Polymer Substrate to the Retina.

Objective We propose a novel attachment method for retinal tissue that utilizes silicone modified with bioactive molecules. Design This is an experimental study divided into an in vitro section performed in cadaveric pig eyes and an in vivo section performed in rabbits. Subjects During in vitro experiments 36 cadaveric pig eyes were used. During in vivo experiments 4 rabbits were used. Methods Different types of silicone went through a laser irradiation process to determine if binding sites for disintegrins could be created. Laser treated silicones that showed disintegrin binding were evaluated with in vitro testing for retina-silicone attachment. The best silicone binding in vitro was implanted into a rabbit's eye after a full vitrectomy was performed. Post-operative exams were done every two weeks to evaluate placement, attachment and sterilization method. After three months animals were euthanized and eye was enucleated for histology analysis. Main Outcome Measures Attachment strength between silicone-disintegrin-retina, and signs of endophthalmitis during in vivo studies for biocompatibility purposes. Results A technique to successfully lase and produce an active area on the silicone surface was described. Scanning electron microscope (SEM) images were evaluated to assess physical ablation/debris field area on the surface, definition of edges, evenness, and symmetry of the lased area allowing us to select MED 4800 silicone family for further testing. Cell culture experiments showed disintegrin binding to the silicone active area. In vitro experiments with cadaveric eyes were performed to test retina-silicone attachment. MED 4860 showed strongest attachment to the retina and it was used during in vivo experiments. A sterilization protocol was tested and proved to be reliable for bioactive materials. Disintegrin coated silicone showed attachment in 2 of 4 rabbits during the 3-month implant period. The adhesion was persistent until reversed with plasmin. All rabbits were implanted for 3 months regardless of attachment, to test the feasibility of the sterilization method. None of the rabbits developed any type of eye infection during the implant period. Conclusion We successfully lased and produced an active area on the silicone surface to allow disintegrin-silicone binding. Different silicones interact differently with the laser energy, and this is reflected in the strength of the silicone-disintegrin-retina attachment.
Evaluating the evolution and function of the dynamic Venom Y protein in ectoparasitoid wasps.

Venom of the parasitoid wasp Nasonia vitripennis changes the metabolism and gene expression in its fly host Sarcophaga bullata to induce developmental arrest, suppression of the immune response and various other venom effects. Yet, the venom of ectoparasitoid wasps has not been fully characterized. A major component of N. vitripennis venom is an uncharacterized, high-expressing protein referred to as Venom Y. Here we describe the evolutionary history and possible functions of this venom protein. We found that Venom Y is a relatively young gene that has duplicated to form two distinct paralogue groups. A copy of Venom Y has been recruited as a venom protein in at least five wasp species. Functional analysis found that Venom Y affects detoxification and immunity genes in envenomated fly hosts. Many of these genes are fat-body specific, suggesting that Venom Y may have a targeted effect on fat body tissue. We also show that Venom Y may mitigate negative effects of other venom proteins. Finally, protein sequencing indicates that Venom Y is post-translationally modified. This study contributes to elucidating parasitoid venom by using RNA interference knockdown to investigate venom protein function in the context of the whole venom cocktail.
Much More than a Clinic: Chicago's Free Health Centers 1968-1972.

Drawing on archival evidence, I document the emergence and florescence of three free health clinics in Chicago in the late 1960s. I trace the centers’ forceful removal by the city’s Board of Health...
Affective Monitor: A Process of Data Collection and Data Preprocessing for Building a Model to Classify the Affective State of a Computer User

This paper outlines the first phase of our implementation of a system for non-intrusive estimation of a computer user’s affective state based on the Circumplex Model of Affect [1], from monitoring the user’s pupil diameter and facial expression [2]. The details of the original design plan for this system have been described previously [2]. The outline describes each part of data collecting process including: Obtaining 3D facial coordinates by Kinect, recording the pupil diameter signal, embedding the facial expression to Facial Animation Parameter indices, and the description of how the experiment will be setup.
The Impact of Basal Septal Hypertrophy on Outcomes after Transcatheter Aortic Valve Replacement.

Background The role of basal septal hypertrophy (BSH) on preprocedural transthoracic echocardiography in transcatheter aortic valve replacement (TAVR) is unknown. Methods Medical charts and preprocedural transthoracic echocardiograms of 378 patients who underwent TAVR were examined. The association between BSH and the primary composite outcome of valve pop-out, recapture, embolization, aborted procedure, conversion to open procedure, new conduction disturbance, or need for permanent pacemaker ≤30 days after TAVR was evaluated. Patients with preexisting pacemakers were excluded. Sensitivity analyses were performed varying the definition of BSH. Results Of 296 TAVR patients (78.3%) with interpretable images, 55 (18.6%) had BSH at a median of 40 days (interquartile range, 19–62 days) before TAVR. Age and sex were similar among those with and without BSH. BSH patients received postdilation more frequently (BSH+ vs BSH−: 41.8% vs 29.9%, P = .04). A total of 50 individuals (16.9%) received pacemakers within 30 days, and 128 (43.2%) developed conduction disturbances (with left bundle branch block most common), without differences between groups. BSH was unrelated to the primary outcome on multivariate analysis (adjusted odds ratio BSH+ vs BSH−, 0.94; 95% CI, 0.42−2.11; P = .88). Conclusions In this convenience sample of TAVR recipients at a large academic medical center, patients with BSH were more likely to receive postdilation. BSH was not associated with procedural or conduction outcomes after TAVR in patients without preexisting pacemakers.
Structural and Functional Characterization of Dynamic Oligomerization in Burkholderia cenocepacia HMG-CoA Reductase

The enzyme 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase (HMGR), in most organisms, catalyzes the four-electron reduction of the thioester (S)-HMG-CoA to the primary alcohol (R)-mevalon...
Type II non-ribosomal peptide synthetase proteins: structure, mechanism, and protein-protein interactions

Covering: 1990 to 2019 Many medicinally-relevant compounds are derived from non-ribosomal peptide synthetase (NRPS) products. Type I NRPSs are organized into large modular complexes, while type II NRPS systems contain standalone or minimal domains that often encompass specialized tailoring enzymes that produce bioactive metabolites. Protein-protein interactions and communication between the type II biosynthetic machinery and various downstream pathways are critical for efficient metabolite production. Importantly, the architecture of type II NRPS proteins makes them ideal targets for combinatorial biosynthesis and metabolic engineering. Future investigations exploring the molecular basis or protein-protein recognition in type II NRPS pathways will guide these engineering efforts. In this review, we consolidate the broad range of NRPS systems containing type II proteins and focus on structural investigations, enzymatic mechanisms, and protein-protein interactions important to unraveling pathways that produce unique metabolites, including dehydrogenated prolines, substituted benzoic acids, substituted amino acids, and cyclopropanes.
Circularvektion, optische Pseudocoriolis-Effekte und optokinetischer Nachnystagmus

Bei 20 Vpn wurde eine vergleichende Untersuchung der subjektiven und optomotorischen Nachwirkungen optokinetischer Reizung durchgefuhrt: Circularvektion, Auslosbarkeit optischer Pseudocoriolis-Effekte, Hemmung vestibularer Coriolis-Effekte nach optischen Bewegungsreizen bei gleichformiger Eigendrehung und optokinetischer Nachnystagmus. Als Reizapparatur diente eine geschlossene Drehtrommel, in deren Innerem sich ein Drehstuhl befindet. Optische Drehreize und Eigendrehung wurden unabhangig voneinander dargeboten (Reizmustergeschwindigkeiten: 60 und 110°/sec; Reizexpositionszeiten: 5 und 30 sec). Die Augenbewegungen wurden elektronystagmographisch registriert, die Intensitat der Coriolis-Effekte durch Grosenskalierung (magnitude estimation) bestimmt. Die psychophysischen Ergebnisse werden unter Berucksichtigung neuronenphysiologischer Experimente und von Ausschaltungsversuchen bei Tieren diskutiert. Die verschiedenen optokinetischen Nacheffekte werden als Ausdruck einer gemeinsamen Erregungskonstellation in der Formatio reticularis und den Vestibulariskernen gedeutet. Die Nachdauer der Effekte wird durch unterschiedliche Schwellen der subjektiven Phanomene und des Nystagmus erklart.
Clinical Characteristics and Adverse Impact of Hepatotoxicity due to Immune Checkpoint Inhibitors.

INTRODUCTION:We conducted this study to characterize the incidence, clinical features, treatment, and outcomes of immune checkpoint inhibitor (ICI) hepatotoxicity.METHODS:Patients who received ICIs (with either single-agent or combination regimens) from January 1, 2010, to March 31, 2018, were ident
Identifying multiple learning spaces within a single teacher-focused Twitter hashtag

Abstract The existing work on teacher-focused Twitter hashtags typically frames each hashtag as a single, unified phenomenon, thereby collapsing or erasing differences between them (and any resulting implications for learning). In this study, we conceived of teacher-focused hashtags as affinity spaces potentially containing subspaces distinguished by synchronous chats and other, asynchronous communication. We used computational methods to explore how participation differed in terms of content, interactions, and portals between these contexts within the #michED hashtag used by Michigan teachers. During the 2015–2016 academic year, #michED saw more non-chat activity than chat activity, and most participants only engaged in one mode of activity or the other. Participation during chats was associated with more replying as well as more socially-, affectively-, and cognitively-related content, suggesting a focus on social interaction. In contrast, non-chat participation was associated with more retweeting, mentioning, hyperlinks, and hashtags, suggesting a focus on content dissemination. These results suggest that different affinity spaces—and different literacy practices—may exist within the same hashtag to support different objectives. Teachers, teacher educators, and researchers should therefore be careful to make these distinctions when considering Twitter as a learning technology for teachers.
A Hazardous Inquiry: The Rashomon Effect at Love Canal

Preface Abbreviations Background 1. Rashomon 2. Love's Canal Accounts 3. Hooker's Account 4. The School Board's Account 5. Digression: Growing Concern about Trace Poisons 6. Ring 1's Account (May to August 1978) 7. Lois Gibbs's Account (June 1978 to May 1980) 8. The Health Department's Account 9. Michael Brown's Account Analysis 10. News Coverage 11. Who Pays? 12. The Scientific Controversy 13. Reconciling Accounts Postscript Chronology The Basics of Toxicology References Index
Immune Checkpoint Inhibitor-Associated Optic Neuritis.

Abstract The three classes of immune checkpoint inhibitors can be associated with optic neuritis, which typically presents with bilateral, painless visual decline. Visual function stabilized with drug cessation and systemic steroids.
Ultrasound Training in Radiology Residency Programs: A National Survey.

Objectives Comprehensive training in ultrasound (US) imaging during radiology residency is crucial if radiologists are expected to maintain a substantial role in this widely used imaging modality. This study aimed to evaluate the current curriculum of US training among radiology residency programs across the country via a nationwide survey. Methods A 28-question survey was distributed among all academic radiology departments in the United States and their radiology residents. The survey consisted of 4 sections: general demographic information, training information, clinical competency, and adequacy of training (perspective). The Student t test and 1-way analyses of variance were performed to assess statistical significance. Results Overall, 256 residents from 32 states completed the questionnaire. Only 114 (45%) residents reported having a dedicated rotation for performing US studies. Although 228 (89%) of trainees believed they received adequate experience for interpreting US studies, only 66 (26%) of them had the same belief about performing them. Only 116 (45%) of the residents were comfortable operating the US machines in their departments. Higher years of residency training, having a dedicated rotation for performing US studies, and having more than 10 hours per year of didactic lectures and/or more than 5 hours per year of case conferences dedicated to US had a positive impact on the residents' clinical competency and perspective (all P Conclusions Most radiology residents do not feel confident in performing US examinations by themselves. However, higher clinical competency was reported in the residents who had dedicated rotations for performing US studies and received more hours of US lectures and case conferences throughout their residency.
Chondrocytes respond both anabolically and catabolically to impact loading generally considered non-injurious.

Abstract We aimed to determine the longitudinal effects of low-energy (generally considered non-injurious) impact loading on (1) chondrocyte proliferation, (2) chondroprogenitor cell activity, and (3) EGFR signaling. In an in vitro study, we assessed 127 full-thickness, cylindrical osteochondral plugs of bovine cartilage undergoing either single, uniaxial unconfined impact loads with energy densities in the range of 1.5–3.2 mJ/mm 3 or no impact (controls). We quantified cell responses at two, 24, 48, and 72 h via immunohistochemical labeling of Ki67, Sox9, and pEGFR antibodies. We compared strain, stress, and impact energy density as predictors for mechanotransductive responses from cells, and fit significant correlations using linear regressions. Our study demonstrates that low-energy mechanical impacts (1.5–3.2 mJ/mm 3 ) generally stimulate time-dependent anabolic responses in the superficial zone of articular cartilage and catabolic responses in the middle and deep zones. We also found that impact energy density is the most consistent predictor of cell responses to low-energy impact loading. These spatial and temporal changes in chondrocyte behavior result directly from low-energy mechanical impacts, revealing a new level of mechanotransductive sensitivity in chondrocytes not previously appreciated.
Experience With Advance Care Planning Discussions Among Pregnant Women With Congenital Heart Disease.

Abstract Context Women with adult congenital heart disease (ACHD) have an increased risk of adverse events during pregnancy. Advance care planning may therefore be an appropriate component of prenatal care. Objective The aim of this study was to describe the perspectives of women with ACHD surrounding advance care planning during pregnancy. Methods We conducted a thematic analysis of 25 semi-structured interviews with women with ACHD who had been pregnant. Purposive sampling was used to gain diversity in ACHD lesion complexity, race, age at pregnancy, and marital status. Results Mean age at pregnancy was 29 years (range 15–41 years), and ACHD was classified as simple (24%), moderate (44%), or complex (32%). We identified three primary themes: 1) the role of advance care planning in being prepared and providing security for family; 2) reasons for avoiding advance care planning, including its lower priority among more pressing concerns and the impact it might have on their current psychological state; and 3) varied openness to advance care planning discussions during pregnancy. Conclusion Advance care planning is not a routine part of prenatal care in ACHD, and its role in this population requires further assessment.
Active wide-field sky simulator design for the JPL astrometry testbed

Measuring the astrometric singal of an exoplanet is an unambiguous method for determining its mass. However, Earth-like planets around Sun-like stars only cause 0.3 uas astrometric signals, which is too small for current instruments to detect. To advance these instruments, an astrometry testbed was created. It can simulate and measure equivalent signals with the use of an illuminated pinhole array and a flexurized pinhole that is translatable to 10 pm resolution. Optical distortions are calibrated with the use of a diffractive pupil. This paper presents the requirements, design, and implementation of the wide-field astrometry testbed’s light source.
Finite-temperature many-body perturbation theory for electrons: Algebraic recursive definitions, second-quantized derivation, linked-diagram theorem, general-order algorithms, and grand canonical and canonical ensembles

A comprehensive and detailed account is presented for the finite-temperature many-body perturbation theory for electrons that expands in power series all thermodynamic functions on an equal footing. Algebraic recursions in the style of the Rayleigh–Schrodinger perturbation theory are derived for the grand potential, chemical potential, internal energy, and entropy in the grand canonical ensemble and for the Helmholtz energy, internal energy, and entropy in the canonical ensemble, leading to their sum-over-states analytical formulas at any arbitrary order. For the grand canonical ensemble, these sum-over-states formulas are systematically transformed to sum-over-orbitals reduced analytical formulas by the quantum-field-theoretical techniques of normal-ordered second quantization and Feynman diagrams extended to finite temperature. It is found that the perturbation corrections to energies entering the recursions have to be treated as a nondiagonal matrix, whose off-diagonal elements are generally nonzero within a subspace spanned by degenerate Slater determinants. They give rise to a unique set of linked diagrams—renormalization diagrams—whose resolvent lines are displaced upward, which are distinct from the well-known anomalous diagrams of which one or more resolvent lines are erased. A linked-diagram theorem is introduced that proves the size-consistency of the finite-temperature many-body perturbation theory at any order. General-order algorithms implementing the recursions establish the convergence of the perturbation series toward the finite-temperature full-configuration-interaction limit unless the series diverges. The normal-ordered Hamiltonian at finite temperature sheds light on the relationship between the finite-temperature Hartree–Fock and first-order many-body perturbation theories.
Extrachromosomal DNA in HPV-Mediated Oropharyngeal Cancer Drives Diverse Oncogene Transcription.

Purpose: Human papillomavirus (HPV) plays a major role in oncogenesis and circular extrachromosomal DNA (ecDNA) is found in many cancers. However, the relationship between HPV and circular ecDNA in human cancer is not understood. Experimental Design: Forty-four primary tumor tissue samples were obtained from a cohort of patients with HPV-positive oropharynx squamous cell carcinoma (OPSCC). Twenty-eight additional HPV oropharyngeal cancer (HPVOPC) tumors from The Cancer Genome Atlas (TCGA) project were analyzed as a separate validation cohort. Genomic, transcriptomic, proteomic, computational, and functional analyses of HPVOPC were applied to these datasets. Results: Our analysis revealed circular, oncogenic DNA in nearly all HPVOPC, with circular human and human–viral hybrid ecDNA present in over a third of HPVOPC and viral circular DNA in remaining tumors. Hybrid ecDNA highly express fusion transcripts from HPV promoters and HPV oncogenes linked to downstream human transcripts that drive oncogenic transformation and immune evasion, and splice multiple, diverse human acceptors to a canonical SA880 viral donor site. HPVOPC have high E6*I expression with specific viral oncogene expression pattern related to viral or hybrid ecDNA composition. Conclusions: Nonchromosomal circular oncogenic DNA is a dominant feature of HPVOPC, revealing an unanticipated link between HPV and ecDNA that leverages the power of extrachromosomal inheritance to drive HPV and somatic oncogene expression.
Experiencing the New Orleans Sniping Forty Years Later: A Review of the Phenomenological Case Study of Constituting the Other

In this book review I explore the published work of Frances Chaput Waksler entitled The New Orleans Sniper: A Phenomenological Case Study of Constituting the Other. The author examines how the second New Orleans sniper was constituted and then later unconstituted, while following the recommendations of Edmund Husserl’s on exploring the how, in a known situation, the Other was constituted; how people constitute an Other in a particular situation with the use of “their general procedures and resources,” where the existence of the Other is problematic (Waksler, 2012).
Hankel and Toeplitz operators in linear quadratic and H:0s ∞ 0E-designs

The structures of the Hankel and Tthe oeplitz operators of the linear quadratic optimization and the H∞- design are studied. The relations between these two design methodologies can be identified via this common operator theoretic interpretation. In particular, the computational burden of the H∞- synthesis can be alleviated by the linear quadratic approximation. The alternative algorithms, convergence properties, and error bounds of the linear quadratic approximation are discussed. The similarities and differences between the linear quadratic approximation and the ϵ-iteration are presented. Finally, simulation results are provided.
The Internet Book: Everything You Need to Know about Computer Networking and How the Internet Works

From the Publisher: The Internet Book examines computer networking and the Internet from a nontechnical perspective. It explains how computers communicate, what the Internet is, how the Internet works, and what the Internet can do for you. No background is required because early chapters clearly explain the terminology and concepts. The book focuses on fundamentals - it describes basic Internet capabilities and shows how they apply to a variety of services. When you finish reading, you will know what the Internet is, how it can be used, and why people find it so exciting. In addition, you will understand the origins of the Internet and why it is growing so rapidly. More important, you will understand the potential ways the Internet can change your life.
Gangliosides attenuate ethanol-induced apoptosis in rat cerebellar granule neurons.

Ethanol significantly enhances cell death of differentiated rat cerebellar granule neurons on culture in a serum-free medium containing a depolarizing concentration of KCl (25 mM), 5 μM MK-801 (an NMDA receptor antagonist), and 20–200 mM ethanol for 1–4 days. Cell death augmented by ethanol was concentration- and time-dependent with neurons displaying hallmark apoptotic morphology and DNA fragmentation that correlated with the activation of cytosolic caspase-3. Inclusion of 5 μM MK-801 or 100 μM glycine in culture media did not alter rates of cell death indicating ethanol toxicity is mediated via an NMDA receptor-independent pathway. Preincubation with 50 μM gangliosides GM1, GD1a, GD1b or GT1b for 2 h, or preincubation with 10 μM LIGA20 (a semisynthetic GM1 with N-dichloroacetylsphingosine) for 10 min, attenuated caspase-3 activity and ethanol-induced cell death. Data show native gangliosides and a synthetic derivative are potently neuroprotective in this model of ethanol toxicity, and potentially serve as useful probes to further unravel the mechanisms relevant to neuronal apoptosis.
Optimization of experimental conditions in preparative liquid chromatography : Trade-offs between recovery yield and production rate

Abstract The optimization of the experimental conditions in preparative chromatography under constraints of recovery yield, product purity and maximum available pressure is discussed. It is shown that there are optimum values of the loading factor and the column limit efficiency which permit the achievement of the maximum production rate under specified constraints of recovery yield and product purity. The optimum loading factor is given by a simple equation. The optimum column efficiency is calculated from numerical solutions of the semi-ideal model. The optimum column length for a given packing material and particle size and the optimum mobile phase velocity are then derived. These optimum values depend on the maximum available pressure, and the production rate increases rapidly with increasing pressure. If a given column is available and it is shorter than the optimum length, it should be operated at the optimum loading factor and at the optimum column efficiency. The mobile phase velocity, and hence the production rate, are less than those for the column of optimum length. If the column is longer than the optimum and cannot be cut, it should be operated at the maximum available pressure, at a mobile phase velocity lower than the optimum and with a loading factor larger than the optimum.
Tissue and Cell Samples by HRMAS NMR

The solid-state NMR line-narrowing technique termed magic-angle spinning (MAS) has been well known to chemists and physicists since the mid-twentieth century, but has only recently been applied to the measurement of proton NMR signals from biological tissue and cell samples. Previously, proton NMR measurements of tissue and cell samples were performed through conventional liquid-state NMR, resulting in broad-line spectra and destruction of the tissue. High-resolution MAS (HRMAS) NMR permits intact tissue analysis where high-resolution proton NMR measurements of tissue samples can be acquired while preserving architectural structures, thus allowing subsequent histopathological analysis on the same tissue. Since this discovery, the methodology has provided the driving force for many studies designed to investigate human physiology and pathology, animal models of human diseases, and intact cells through the evaluation of tissue specimens. Specifically in the study of human malignancy, the application of metabolomics has become an especially active area of research. After further developments in both imaging technology and the characterization of metabolic profiles, it seems likely that clinical implementation will occur, either in the identification of metabolomic pathology or for in vivo disease characterization. Keywords: proton NMR; high-resolution magic angle spinning (HRMAS); magnetic resonance spectroscopy (MRS); magnetic resonance imaging (MRI); tissue histopathology; human malignancy; disease diagnosis; metabolomics
Beowulf’S Boast Words

This paper focuses on two types of “boast words” as they are used in Beowulf. The first type to be considered is the act of speaking we commonly associate with bragging, while the second, more important kind of boast, functions as a promise that the speaker will perform specific acts of courage. Close examination of Beowulf’s speeches in their narrative contexts shows that type one boasts, as they are defined here, help to establish Beowulf’s credibility as a man who can be trusted to do what he says he will do, while type two boasts show the degree to which he commits himself to follow through on his promises. Attention is also given to the boast words Wiglaf utters as he comes to the aid of his king, and to words spoken by J.R.R. Tolkien’s Lord of the Rings heroes that also function, in their much later contexts, as type two, heroic promise boasts.
LA ÉTICA DEL DEFAULT: POR QUÉ ALGUNAS DEUDAS NO SON OBLIGATORIAS PARA LAS GENERACIONES ACTUALES

In this article I argue that many debtor countries are morally entitled to default on a big portion of their sovereign debts. I will do this by showing that exceptions to the general claim that governments have the obligation to repay debts incurred by past governments should be made.
Genethics: “Planned Parenthood”

This case is another in a series intended to highlight the new questions emerging from advances in mapping the human genome and the application of genetic findings to clinical practice. The National Human Genome Research Institute, a component of the National Institutes of Health, by law is directed to designate a portion of its annual budget to furthering understanding of the ethical, legal, and social questions emerging from research on the human genome. As part of the effort, the Institute supports research by scientists and scholars around the nation with the aim of clarifying and resolving the tough ethical and research choices facing this endeavor. But recently it has launched an intramural program, which is expected to take a catalytic role in grappling with the array of issues the researchers face in carrying out investigations in human genetics.
Modification of Schwann cell gene expression by electroporation in vivo

Clinical outcomes of nerve grafting are often inferior to those of end-to-end nerve repair. This may be due, in part, to the routine use of cutaneous nerve to support motor axon regeneration. In previous work, we have demonstrated that Schwann cells express distinct sensory and motor phenotypes, and that these promote regeneration in a modality-specific fashion. Intra-operative modification of graft Schwann cell phenotype might therefore improve clinical outcomes. This paper demonstrates the feasibility of electroporating genes into intact nerve to modify Schwann cell gene expression. Initial trials established 70 V, 5 ms as optimum electroporation parameters. Intact, denervated, and reinnervated rat tibial nerves were electroporated with the YFP gene and evaluated serially by counting S-100 positive cells that expressed YFP. In intact nerve, a mean of 28% of Schwann cells expressed the gene at 3 days, falling to 20% at 7 days with little expression at later times. There were no significant differences among the three groups at each time period. Electronmicroscopic evaluation of treated, intact nerve revealed only occasional demyelination and axon degeneration. Intra-operative electroporation of nerve graft is thus a practical means of altering Schwann cell gene expression without the risks inherent in viral transfection.
A Photorefractive Integrated Optical Vector Matrix Multiplier

A method for implementing general linear transformations on one dimensional optical field distributions in integrated optics is described. This method uses the Bragg selectivity of volume holograms to replace one dimension of the bulk optical vector matrix multiplier. A means of writing appropriate matrices optically using unguided light is also described. Experimental results are presented which demonstrate the diffraction of guided light by holograms written with unguided beams.
Recent advances in the management of early onset scoliosis.

KEY POINTS Current literature supports the use of serial casting for most progressive early onset spinal deformities as either a definitive or a surgical delay treatment. If and when surgery is required for early onset scoliosis treatment, the most commonly used system is growing rods, but this may change in the future with other viable options undergoing research, including magnetically controlled growing rods, nitinol staples, tethering, and the Shilla procedure. Expansion thoracoplasty is generally recommended for patients with thoracic insufficiency syndrome. Future goals include scoliosis treatment methods that involve less complications and to successfully treat patients with “fusionless” methods.
609 Echocardiography and Its Role in the Diagnosis and Prognosis of Congenital Heart Disease in Children

609 Echocardiography and Its Role in the Diagnosis and Prognosis of Congenital Heart Disease in Children
Change in women's diet and body mass following intensive intervention for early-stage breast cancer

Abstract Objective To determine the effectiveness of an intensive dietary intervention on diet and body mass in women with breast cancer. Design Randomized clinical trial. Subjects 172 women aged 20 to 65 years with stage I or II breast cancer. Intervention A 15-session, mainly group-based and dietitian-led nutrition education program (NEP) was compared to a mindfulness-based stress reduction clinic program (SRC); or usual supportive care (UC). Main outcome measures Dietary fat, complex carbohydrates, fiber, and body mass were measured. Statistical analysis In addition to descriptive statistics, analysis of variance was conducted to test for differences according to intervention group. Results Of the 157 women with complete dietary data at baseline, 149 had complete data immediately postintervention (at 4 months) and 146 had complete data at 1 year. Women randomized to NEP (n=50) experienced a large reduction in fat consumption (5.8% of energy as fat) at 4 months and much of this reduction was preserved at 1 year (4.1% of energy) (both P .0002) vs no change in either SRC (n=51) or UC (n=56). A 1.3-kg reduction in body mass was evident at 4 months in the NEP group ( P =.003) vs no change in the SRC and UC groups. Women who had higher-than-average expectations of a beneficial effect of the intervention experienced larger changes. Applications Dietitians' use of group nutrition interventions appear to be warranted. Increasing their effectiveness and maintaining high levels of adherence may require additional support, including the involvement of significant others, periodic individual meetings, or group booster sessions. J Am Diet Assoc. 2001; 101:421–428, 431.
Exchange across a sediment–water interface with ambient groundwater discharge

Summary We investigate the interaction between turbulent water-column flow, current-topography-driven flow in underlying permeable sediments, and ambient groundwater discharge (AGD) from/to deep groundwater. Turbulent flow in the water column is simulated using a k–ω model and linked to a Darcian model of pore-water flow. AGD reduces the spatial extent of the current-topography driven interfacial exchange zone (IEZ) within the sediments and prevents its development when turbulent flow cannot induce sufficient pressure gradients along the sediment–water interface (SWI) to overcome AGD. A Morgan–Mercer–Flodin-type model describes how the presence and size of the IEZ depends on water-column Reynolds number (Re) and AGD, while the IEZ flux dependence is described by a power model. The mean residence time of water flowing through the IEZ is large at low Re, when the IEZ is of limited spatial extent, decreases at higher Re when the IEZ is more extensive, and decreases with the presence of AGD. Although metrics for interfacial exchange (size, flux and mean residence time) look similar for both upward and downward AGD, the geometry of the IEZ is different. For upward AGD, the IEZ is centered on the bottom-pressure maximum along the stoss face of dunes, near where the water-column eddy reattaches. Deep groundwater upwells near the bottom-pressure minimum which is located at the crest. Under downward AGD, the IEZ forms around the pressure minimum at the crest. The water column downwells near the bottom-pressure maximum along the stoss face, some water downwelling deep into the sediments and not returning to the SWI.
Modeling to evaluate the response of savanna-derived cropland to warming–drying stress and nitrogen fertilizers

Many savannas in West Africa have been converted to croplands and are among the world’s regions most vulnerable to climate change due to deteriorating soil quality. We focused on the savanna-derived cropland in northern Ghana to simulate its sensitivity to projected climate change and nitrogen fertilization scenarios. Here we show that progressive warming–drying stress over the twenty-first century will enhance soil carbon emissions from all kinds of lands of which the natural ecosystems will be more vulnerable to variation in climate variables, particularly in annual precipitation. The carbon emissions from all croplands, however, could be mitigated by applying nitrogen fertilizer at 30–60 kg N ha − 1 year − 1. The uncertainties of soil organic carbon budgets and crop yields depend mainly on the nitrogen fertilization rate during the first 40 years and then are dominated by climate drying stress. The replenishment of soil nutrients, especially of nitrogen through fertilization, could be one of the priority options for policy makers and farm managers as they evaluate mitigation and adaptation strategies of cropping systems and management practices to sustain agriculture and ensure food security under a changing climate.
The elaboration of technology of preparation of adsorption ion exchange materials in the basis of rice waste

The results of investigations of agricultural waste (rice husk) processing are presented. The kinetics of processing of cellulose and cation-exchange material, having high exchange capacity is determined, and the technology of its production is proposed. The influence of the temperature, esterification time, and the volume of phosphorus acid on exchange capacities of produced sorption materials are determined.
Collar options to manage revenue risks in real toll public‐private partnership transportation projects

The revenue risk is of great importance to ensure the success of a real toll public–private partnership (PPP) transportation project. Past research has proposed a revenue guarantee put option as an alternative way to quantify and potentially manage this risk. A practical, or commercial, limitation of this type of option is its requirement for an upfront premium payment, and a concessionaire is likely to shy away from additional monetary requirements. A collar option, which is a combination of a put and call option, not only overcomes this barrier but it also provides other benefits. Modifications to the basic collar’s structure can redistribute downside losses and upside profits to fulfil stakeholders’ needs and thus improve the effectiveness of risk management. The terms, applicability and limitations of a collar option are discussed, and a numerical example is developed to illustrate how to determine the strike prices of a collar option.
Geochronology and eruptive history of the Katmai volcanic cluster, Alaska Peninsula

Abstract In the Katmai district of the Alaska Peninsula, K–Ar and 40Ar/39Ar ages have been determined for a dozen andesite–dacite stratocones on the arc front and for 11 rear-arc volcanoes, 10 of which are monogenetic. Tied to mapping and stratigraphic studies, our dating emphasized proximal basal lavas that rest on basement rocks, in order to estimate ages of inception of each polygenetic cone. Oldest among arc-front cones is Alagogshak Volcano (690–43 ka), succeeded in the Holocene by the active Mount Martin cone. Mount Mageik consists of four overlapping subedifices, basal lavas of which give ages of 93, 71, and 59 ka, and Holocene. The three small prehistoric cones of Trident Volcano yield ages of 143, 101–58, and 44 ka. Falling Mountain and Mount Cerberus, dacite domes near the 1912 Novarupta vent, are related compositionally to the Trident group and give ages of 70 ka and 114 ka. Mount Katmai, which underwent caldera collapse in 1912, consists of two subedifices that overlapped in space and time, and is the only arc-front center here to include basalt and rhyolite; one cone began by 90 ka, the other by 47 ka. Snowy Mountain also consists of two contiguous cones, which started around 200 and 171 ka, respectively, the younger remaining active into the Holocene. Devils Desk, the only mafic cone on the arc front, was short-lived at about 245 ka. In the rear-arc, (1) Mount Griggs produced mafic-to-silicic andesite in several episodes between 292 ka and the Holocene; (2) the Savonoski River cluster includes a Pliocene dacite dome and five small mafic cones (390–88 ka); (3) Gertrude Creek cone (49.8% SiO2) yields an age of 500 ka; and (4) the Saddlehorn Creek cluster includes five Pliocene basalt-to-andesite remnants. Eruptive volumes were reconstructed, permitting estimates of average eruption rates for edifice lifetimes. Since the mid Pleistocene, total volume erupted along the arc front here is 210±47 km3 and in the rear-arc 39±6 km3, of which Mount Griggs alone accounts for 35±5 km3. Most productive has been Mount Katmai at 70±18 km3, yielding a rate of ∼1 km3/kyr, followed by Mount Mageik (0.33 km3/kyr) and Mount Griggs (0.3 km3/kyr since 50 ka).
Instabilities and bifurcations in a rotating shaft

Abstract Flexural vibrations of a slender, balanced rotating shaft are considered. The shaft is of circular cross-section, it rotates at a constant rate about its longitudinal axis of symmetry, and is made of a viscoelastic material. The effects of large transverse displacements and external sources of dissipation are also included. The resulting non-linear model is analyzed for stability and bifurcations of the trivial shaft configuration (the undeformed, straight position). The instabilities are predicted by using the linearized shaft model and the post-critical behaviors are determined by applying center manifold theory to the full non-linear equations of motion. The bifurcations encountered are simple Hopf, double Hopf, and double zero eigenvalues. It is determined that synchronous whirl, non-synchronous whirl, and competing-mode types of behavior are possible for various ranges of the parameter values. The results obtained prove that the modal truncations typically used when analyzing continuous shaft instabilities are mathematically justifiable.
Fyn and JAK2 mediate Ras activation by reactive oxygen species.

Reactive oxygen species (ROS) activate Ras and the extracellular signal-regulated kinase (ERK) cascade. Because JAK2 is a critical mediator for Ras/Raf/ERK activation by several hormones, we examined the role of JAK2 in ROS signal events. H2O2 stimulated JAK2 activity in fibroblasts with peak at 2–5 min. To determine the specific role of Src and Fyn as mediators of JAK2 activation and its downstream events, we used fibroblasts derived from transgenic mice deficient in Src (Src−/−) or Fyn (Fyn−/−). H2O2-stimulated JAK2 activity was completely inhibited in Fyn−/− cells. Shc tyrosine phosphorylation and Ras activation by H2O2 were also significantly reduced in Fyn−/− cells, but not altered in Src−/− cells. Activation of JAK2 was restored when Fyn−/− cells were transfected with B-Fyn but not with Src. Inhibiting JAK2 activity with the specific inhibitor AG-490 prevented H2O2 stimulated Shc and Ras activation. H2O2-mediated ERK1/2 activation in Fyn−/− cells and AG-490 treated cells was completely inhibited at an early time (5 min), but not at late times (20–40 min) after stimulation. These results define a new redox-sensitive pathway for Ras activation and rapid ERK1/2 activation, which is mediated by Fyn and JAK2.
Stretching and breaking duplex DNA by chemical force microscopy

Abstract Background: Specific interactions between complementary strands of DNA and other molecules are central to the storage, retrieval and modification of information in biological systems. Although in many cases the basic structures of duplex DNA and the binding energetics have been well characterized, little information is available about the forces in these systems. These forces are of critical importance because they must be overcome, for example, by protein machines during transcription and repair. Recent developments in atomic force microscopy make possible direct measurements of such forces between the individual oligonucleotide strands that form DNA duplexes. Results: We used the chemical force microscopy technique, in which oligonucleotides are covalently linked to the force microscope probe tip and the sample surface, to measure the elongation and binding forces of individual DNA duplexes. The separation forces between complementary oligonucleotide strands were found to be significantly larger than the forces measured between noncomplementary strands, and to be consistent with the unbinding of a single DNA duplex. With increasing applied force, the separation of complementary strands proceeded in a stepwise manner: B-form DNA was stretched, then structurally transformed to a stable form of DNA approximately twice the length of the B form, and finally separated into single-stranded oligonucleotides. These data provide a direct measurement of the forces required to elastically deform and separate double-stranded DNA into single strands. Conclusions: Force microscopy provides a direct and quantitative measurement of the forces and energetics required to stretch and unbind DNA duplexes. Because the measurements can be carried out readily on synthetic oligonucleotides and in the presence of exogenous molecules, this method affords an opportunity for directly assessing the energetics of distorting and unbinding specific DNA sequences and DNA complexes. Such data could provide unique insights into the mechanistic steps following sequence-specific recognition by, for example, DNA repair and transcription factors.
Prenatal Diagnosis, Birth Location, Surgical Center, and Neonatal Mortality in Infants With Hypoplastic Left Heart Syndrome

Background—Most studies have not demonstrated improved survival after prenatal diagnosis of critical congenital heart disease, including hypoplastic left heart syndrome (HLHS). However, the effect of delivery near a cardiac surgical center (CSC), the recommended action after prenatal diagnosis, on HLHS mortality has been poorly investigated. Methods and Results—Using Texas Birth Defects Registry data, 1999 through 2007, which monitored >3.4 million births, we investigated the association between distance (calculated driving time) from birth center to CSC and neonatal mortality in 463 infants with HLHS. Infants with extracardiac birth defects or genetic disorders were excluded. The associations between prenatal diagnosis, CSC HLHS volume, and mortality were also examined. Neonatal mortality in infants born 90 minutes 39.6% (P for trend <0.001). Prenatal diagnosis alone was not associated with improved survival (P=0.14). In multivariable analysi...
Molecular cloning of cDNA for human von Willebrand factor: authentication by a new method.

Abstract We have identified a 2.4 kb partial cDNA clone (pDL34) for human von Willebrand factor (vWf) mRNA. pDL34 was selected by screening an endothelial cell cDNA library with a radiolabeled reverse transcript of mRNA obtained by specific immunoisolation of vWf polysomes from endothelial cells. pDL34 selectively hybridized to an endothelial cell-associated 9.5 kb mRNA. To confirm its identity, SP6 RNA polymerase was used to generate in vitro transcripts of the cDNA. This synthetic RNA, truncated at its 5′ end, directed the synthesis of several unique polypeptides in rabbit reticulocyte lysates. These polypeptides were immunoprecipitated by polyclonal and monoclonal anti-vWf antibodies. These results indicate that pDL34 contains an authentic partial copy of vWf mRNA. In vitro transcription of partial cDNA clones and translation of the resulting RNAs may be a useful general method of verifying the identity of various cDNA clones in circumstances where antibodies are available and protein sequence is not.
Improved coordination in nonhierarchic system optimization

An improved coordination procedure for the optimization of nonhierarchic systems by decomposition into reduced subspaces is presented. A subspace coordination procedure based on sequential global approximation is extended to include second-order information. This second-order global approximation is formed using information obtained during subspace optimizations. The use of second-order information in the coordination procedure results in improved convergence for nonhierarchic system optimization as compared with the authors' earlier studies using a first-order coordination procedure