cssi/SciSciGPT-SciSciNet huggingface dataset:
Comparative diagnostic performance of ultrasound shear wave elastography and magnetic resonance elastography for classifying fibrosis stage in adults with biopsy-proven nonalcoholic fatty liver disease.

OBJECTIVES To compare the diagnostic accuracy of US shear wave elastography (SWE) and magnetic resonance elastography (MRE) for classifying fibrosis stage in patients with nonalcoholic fatty liver disease (NAFLD). METHODS Patients from a prospective single-center cohort with clinical liver biopsy for known or suspected NAFLD underwent contemporaneous SWE and MRE. AUCs for classifying biopsy-determined liver fibrosis stages ≥ 1, ≥ 2, ≥ 3, and = 4, and their respective performance parameters at cutoffs providing ≥ 90% sensitivity or specificity were compared between SWE and MRE. RESULTS In total, 100 patients (mean age, 51.8 ± 12.9 years; 46% males; mean BMI 31.6 ± 4.7 kg/m2) with fibrosis stage distribution (stage 0/1/2/3/4) of 43, 36, 5, 10, and 6%, respectively, were included. AUCs (and 95% CIs) for SWE and MRE were 0.65 (0.54-0.76) and 0.81 (0.72-0.89), 0.81 (0.71-0.91) and 0.94 (0.89-1.00), 0.85 (0.74-0.96) and 0.95 (0.89-1.00), and 0.91 (0.79-1.00) and 0.92 (0.83-1.00), for detecting fibrosis stage ≥ 1, ≥ 2, ≥ 3, and = 4, respectively. The differences were significant for detecting fibrosis stage ≥ 1 and ≥ 2 (p < 0.01) but not otherwise. At ≥ 90% sensitivity cutoff, MRE yielded higher specificity than SWE at diagnosing fibrosis stage ≥ 1, ≥ 2, and ≥ 3. At ≥ 90% specificity cutoff, MRE yielded higher sensitivity than SWE at diagnosing fibrosis stage ≥ 1 and ≥ 2. CONCLUSIONS In adults with NAFLD, MRE was more accurate than SWE in diagnosing stage ≥ 1 and ≥ 2 fibrosis, but not stage ≥ 3 or 4 fibrosis. KEY POINTS • For detecting any fibrosis or mild fibrosis, MR elastography was significantly more accurate than shear wave elastography. • For detecting advanced fibrosis and cirrhosis, MRE and SWE did not differ significantly in accuracy. • For excluding advanced fibrosis and potentially ruling out the need for biopsy, SWE and MRE did not differ significantly in negative predictive value. • Neither SWE nor MRE had sufficiently high positive predictive value to rule in advanced fibrosis.
Hallucinations: A Functional Network Model of How Sensory Representations Become Selected for Conscious Awareness in Schizophrenia

Hallucinations are conscious perception-like experiences that are a common symptom of schizophrenia spectrum disorders (SSD). Current neuroscience evidence suggests several brain areas are involved in the generation of hallucinations including the sensory cortex, insula, putamen, and hippocampus. But how does activity in these regions give rise to aberrant conscious perceptions that seemingly invade ongoing conscious experience? Most existing models assume that sensory representations are sometimes spontaneously activated in the brain, and that these spontaneous activations somehow play a causal role in the generation of hallucinations. Yet, it remains unclear how these representations become selected for conscious processing. No existing theory of hallucinations has specified such a “selection mechanism.” Global Workspace (GW) theorists argue that the brain’s interconnected processors select relevant piece(s) of information for broadcasting to other brain processors, rendering the information accessible to consciousness; this process known as “ignition” is associated with synchronized activity across distributed cortical and subcortical brain regions. Yet, it remains unclear how certain information and representations become selected for conscious processing. While GW theorists maintain that attention plays an important role, they have not delineated a formal “selection mechanism.” This paper specifies a selection mechanism based upon two central hypotheses: (1) a functional network called the “salience network” plays a critical role in selecting sensory representations for conscious broadcast to the GW in normal (healthy) perception; (2) sensory representations become abnormally selected for conscious broadcast to the GW (instead of being filtered out of consciousness) in individuals with SSD that experience hallucinations.
Optical Stabilization of Semiconductor Lasers

The method of using resonant optical feedback to stabilize the frequency of semiconductor lasers has proved valuable for a number of applications [1–3]. It is one of a number of possible optical stabilization methods, as opposed to electronic stabilization methods, and contrasts from other optical methods in that the optical feedback comes from a high Q (quality factor) optical resonator. This technique for frequency stabilization uses commercially available lasers and Fabry-Perot cavities and can reduce diode laser linewidths to as low as 3 kHz. The resonance of the Fabry-Perot cavity serves as the frequency reference which stabilizes the lasers oscillation frequency and narrows its linewidth.
Scientific Research, Ethics, Scientific Misconduct

Introduction Scientific Misconduct Incidence and Types of Scientific Misconduct Defining Misconduct Plight of the Whistleblower, Plight of the Scientist Ethics and Science History, Sociology, and Philosophy of Science: Looking for Causes of Misconduct History of Scientific Misconduct Governmental Roles in Science and Misconduct Office of Research Integrity Academic and Institutional Roles in Scientific Misconduct Keywords: scientific research; ethics; law
An electrically pumped liquid helium transfer system.

A liquid helium transfer system is described which is capable of maintaining continuous flow at rates as low as one liter per hour for periods up to several days. A superconducting liquid helium pump [1] and a liquid-level sensing system were also developed for use with this line to automatically maintain a fixed helium level in a cryostat. This system was designed for a cryogenic gyro application in which batch transfer of liquid helium could not be used due to resulting large thermal gradients which cause gyro Instrumentation difficulties.
Evaluating Perioperative Outcomes and Efficiency Following Total Joint Arthroplasty in the United States and Canada.

49. Hart A, Khalil JA, Carli A, Huk O, Zukor D, Antoniou J. Blood transfusion in primary total hip and knee arthroplasty: incidence, risk factors, and thirty-day complication rates. J Bone Joint Surg Am. 2014;96(23):1945-1951. 50. McIntyre L, Hebert PC, Wells G, et al; Canadian Critical Care Trials Group. Is a restrictive transfusion strategy safe for resuscitated and critically ill trauma patients? J Trauma. 2004;57(3):563-568.
Vehicle speed control algorithms for data delivery and eco-driving

Recently, V2V/V2I and connected vehicle (CV) technologies have received considerable research interest due to its potential breakthrough applications in eco-driving, road safety, surveillance, infotainment, and many more. In this paper, for the first time in literature, we address the problem of data-aware eco-driving. Specifically, we harnessed the latest V2V/V2I technologies to propose vehicle speed advisory system based on microscopic fuel model that simultaneously minimize fuel consumption and maximize probability of data delivery, thereby making the system flexible in handling sustainability and data dependent applications. Preliminary numerical studies are carried out demonstrating the significance of the problem and the proposed algorithms in terms of fuel and data downloading efficiencies.
The relative lability of floral vs. non-floral characters and a morphological phylogenetic analysis of Cobaea (Polemoniaceae)☆

The relative levels of lability in floral vs. vegetative characters have been suggested to give insight into the mechanisms of adaptation and speciation. Cobaea (Polemoniaceae) exhibits a remarkable diversity in floral form. A morphology-based phylogeny was constructed and is congruent in most regards with a previously published molecular phylogeny, but significant incongruence was found in the placement of two taxa. A combined analysis was performed, excluding C. aquatoriensis and C. lutea, and was nearly identical to the molecular analysis. The phylogenies are compatible with a recently published classification. Incongruencies between the phylogenies within section Rosenbergia may have profound implications for floral evolution. A simple method for testing the levels of homoplasy, as an indicator of lability between two classes of data, is developed and used to test for differences between floral and non-floral classes of characters. The method is based on repeated randomization of the data into partitions and recalculation of a test statistic defined as the difference between consistency index (CI) values of the data in each partition over a given tree. The null hypothesis that the floral characters are no more homoplasious than the non-floral characters cannot be rejected (P=0.09).
Protein kinase Cδ-mediated CREB activation regulates ghrelin-induced cyclooxygenase-2 expression and prostaglandin E2 production in human colonic epithelial cells

Ghrelin, a newly identified gastric peptide, is known for its potent activity in growth hormone release and appetite. Our recent study showed that ghrelin could stimulate protein kinase C-mediated activation of nuclear factor-κB (NF-κB) and interleukin-8 secretion in human colonic epithelial cells transfected with a functional ghrelin receptor. In the present study, the effect of ghrelin stimulation on cyclooxygenese-2 expression and prostaglandin E2 production was examined. The data indicate that ghrelin significantly increased the levels of cyclooxygenase-2 (COX-2) protein as well as its promoter activity, which leaded to profound increase in prostaglandin E2 secretion. In order to examine the involvement of NF-κB and cAMP responsive element-binding protein (CREB) in this response, the NF-κB inhibitory protein IκBα or a dominant negative mutant of CREB was co-transfected into cells and the data show that transfection of either IκBα or DN-CREB significantly attenuated ghrelin-induced COX-2 expression. Moreover ghrelin stimulated phosphorylation of CREB, which was mediated primarily via protein kinase Cδ activation. Furthermore, inhibition of PKCδ function significantly attenuated ghrelin-induced COX-2 expression. In addition, ghrelin stimulates phosphorylation of PKCδ. Together, these results indicate that in addition to NF-κB, protein kinase Cδ-mediated CREB activation plays an important role in the cellular responses of ghrelin. J. Cell. Biochem. 102: 1245–1255, 2007. © 2007 Wiley-Liss, Inc.
Positron Emission Tomography Imaging of the Serotonin Transporter and 5-HT1A Receptor in Alcohol Dependence

Background Rodent models as well as studies in humans have suggested alterations in serotonin (5-HT) innervation and transmission in early-onset genetically determined or type II alcoholism. This study examines two indices of serotonergic transmission, 5-HT transporter levels and 5-HT 1A availability, in vivo, in type II alcoholism. This is the first report of combined tracers for pre- and postsynaptic serotonergic transmission in the same alcoholic subjects and the first study of 5-HT 1A receptors in alcoholism. Methods Fourteen alcohol-dependent subjects were scanned (11 with both tracers, 1 with [ 11 C]DASB only, and two with [ 11 C]WAY100635 only). Twelve healthy control subjects (HC) subjects were scanned with [ 11 C]DASB, and another 13 were scanned with [ 11 C]WAY100635. Binding potential (BP p , mL/cm 3 ) and the specific to nonspecific partition coefficient (BP ND , unitless) were derived for both tracers using a two-tissue compartment model and compared with control subjects across different brain regions. Relationships to severity of alcoholism were assessed. Results No significant differences were observed in regional BP p or BP ND between patients and control subjects in any of the regions examined. No significant relationships were observed between regional 5-HT transporter availability, 5-HT 1A availability, and disease severity, with the exception of a significant negative correlation between 5-HT transporters and years of dependence in amygdala and insula. Conclusion This study did not find alterations in measures of 5-HT 1A or 5-HT transporter levels in patients with type II alcoholism.
Detection of Additional Members of the 2003 EL61 Collisional Family via Near-Infrared Spectroscopy

We have acquired near-infrared spectra of Kuiper Belt objects 2003 UZ117, 2005 CB79, and 2004 SB60 with NIRC on the Keck I telescope. These objects are dynamically close to the core of the 2003 EL61 collisional family and were suggested to be potential fragments of this collision by Ragozzine and Brown. We find that the spectra of 2003 UZ117 and 2005 CB79 both show the characteristic strong water ice absorption features seen exclusively on 2003 EL61, its largest satellite, and the six other known collisional fragments. In contrast, we find that the near-infrared spectrum of 2004 SB60 is essentially featureless with a fraction of water ice of less than 5%. We discuss the implications of the discovery of these additional family members for understanding the formation and evolution of this collisional family in the outer solar system.
Personality pathology and outcome in recurrently depressed women over 2 years of maintenance interpersonal psychotherapy.

Background. Empirical data on the impact of personality pathology on acute treatment outcome for depression are mixed, in part because of challenges posed by assessing trait-like personality patterns while patients are in an active mood episode. To our knowledge, no previous study has examined the effect of personality pathology on maintenance treatment outcome. By maintenance treatment we refer to long-term treatment provided to prevent depression recurrence among remitted patients. Method. Structured Clinical Interviews for the DSM-III-R Personality Disorders (SCID-II) were obtained on a sample of 125 recurrently depressed women following sustained remission of the acute mood episode and prior to entering maintenance treatment. SCID-II interviews were then repeated following 1 and 2 years of maintenance interpersonal psychotherapy. Results. At the pre-maintenance assessment, 21.6% of the sample met SCID-II personality disorder criteria. Co-morbid personality pathology was related to an earlier age of onset, more previous depressive episodes, and a greater need for adjunctive pharmacotherapy to achieve remission of the acute mood episode. Co-morbid personality pathology predicted both higher rates of depression recurrence and a shorter time to recurrence over the 2-year course of maintenance treatment. Notably, among those patients who remained depression-free, continuous levels of personality pathology steadily declined over the 2-year course of maintenance therapy. Conclusions. Results highlight the need for early and effective intervention of both episodic mood disorder and inter-episode interpersonal dysfunction inherent to the personality disorders. Future maintenance treatment trials are needed to clarify the relationship between episodic mood disorder and personality function over time.
The comparative submicroscopic cytology of the corpus allatum-corpus cardiacum complex of wild type and fes adult female Drosophila melanogaster

The submicroscopic morphology of the corpus allatum-corpus cardiacum complex of wild type adult female Drosophila melanogaster is described. These endocrine organs are compared with those of females homozygous for the recessive, female sterile gene, fes. The corpus allatum is known to produce a hormone influencing vitellogenesis. The ultrastructure of the gland suggests that this hormone is synthesized by a smooth surfaced, membranous system organized into a reticulum of filaments and tubules from which vesicles are derived by abscission of terminal and lateral blebs. The allatum cells of genetically ovatectomized, fes females are inhibited from releasing the hormone they synthesize. They swell and undergo characteristic, degenerative changes. The corpus cardiacum consists of a central bundle of axons surrounded by cortical cells. Many of the axons are thought to originate as projections from specialized, secretory neurons residing in the pars intercerebralis. Neurosecretory spheres are carried posteriorly in these axons by traveling bulges. The cortical cells contain myriads of neurosecretory spheres suspended in their cytoplasm, and most of these are believed to have been donated by contiguous axons. Cortical cells are also characterized by an extensive, rough surfaced, endoplasmic reticulum consisting of interconnected bloated cisternae which arise from localized, blister-like proliferations of the outer membranes of the nuclei. The cortical cells of fes females also swell, and their nuclear blisters reach immense sizes. Vitellogenesis within a wild type ovary previously implanted into the abdomen of fes females is accompanied by release of products from the host allatum and cardiacum cells and the return of these cells to their normal morphologies.
Endonucleolytic processing of covalent protein-linked DNA double-strand breaks

DNA double-strand breaks (DSBs) with protein covalently attached to 5' strand termini are formed by Spo11 to initiate meiotic recombination. The Spo11 protein must be removed for the DSB to be repaired, but the mechanism for removal is unclear. Here we show that meiotic DSBs in budding yeast are processed by endonucleolytic cleavage that releases Spo11 attached to an oligonucleotide with a free 3'-OH. Two discrete Spo11-oligonucleotide complexes were found in equal amounts, differing with respect to the length of the bound DNA. We propose that these forms arise from different spacings of strand cleavages flanking the DSB, with every DSB processed asymmetrically. Thus, the ends of a single DSB may be biochemically distinct at or before the initial processing step-much earlier than previously thought. SPO11-oligonucleotide complexes were identified in extracts of mouse testis, indicating that this mechanism is evolutionarily conserved. Oligonucleotide-topoisomerase II complexes were also present in extracts of vegetative yeast, although not subject to the same genetic control as for generating Spo11-oligonucleotide complexes. Our findings suggest a general mechanism for repair of protein-linked DSBs.
Summation of Large Corrections to Short Distance Hadronic Cross-Sections

Abstract The large soft gluon corrections to short-distance hadronic cross sections are summed to all orders in perturbation theory. The arguments apply to any cross section whose Born contribution is initiated by quarks, including Drell-Yan and heavy vector boson cross sections. The exponentiation of leading and non-leading ln(n) terms in moments of these cross sections is verified. In particular, the ln3(n) terms computed by van Neervan at two loops are rederived on the basis of one-loop calculations.
Postnatal Maturation of the Human Endolymphatic Sac

Objective/Hypothesis The objective of this study was to trace the postnatal development of the human endolymphatic sac. The endolymphatic sac starts as a pouch-like structure during the fetal period in the human but later develops into a complex network of tubules in its mature form. Study Design Observational study. Methods Light microscopic examination of the morphology of the endolymphatic sac in a population of temporal bones. Results Examination of 28 temporal bones from 19 infants and children reveals that endolymphatic sac morphological maturation is usually completed in the first year of life, although it may occur as late as 4 years of age. There was good correlation of maturation levels between sides when pairs of temporal bones were evaluated. Immature pouch-like endolymphatic sacs may appear as late as 4 years of age. Conclusions Endolymphatic sac maturation to its adult tubular form is usually completed by the first year. This finding contrasts with other studies examining the growth of the endolymphatic sac to adult size after birth. Histological evidence suggests that the endolymphatic sac, although not morphologically mature by appearance, may still be participating at some level of functioning.
Recognition and judgment of facial stimuli in schizotypal subjects

Affect recognition abilities, an important component of successful social functioning, were examined in two groups of schizotypal subjects who were identified by the Perceptual Aberration/Magical Ideation and Physical Anhedonia Scales (PABS, MIS, PAS). Prior research has demonstrated social impairments in subjects identified by these scales and in schizophrenics. Although research has shown schizophrenic subjects to have facial affect recognition deficits, the present results did not support the hypothesis that such impairments would appear in subjects exhibiting similar symptoms, but to a less severe degree, when compared with controls. The results suggest that deficits in emotional decoding may appear at a relatively late stage in the developmental course of mental disorder, or may only be associated with more severe levels of schizophrenia-spectrum symptomatology. The paper discusses theoretical and methodological implications for research on the components and development of social deficits in the schizophrenia-spectrum disorders.
Glucocorticoid receptor antagonism in the basolateral amygdala and ventral hippocampus interferes with long-term memory of contextual fear.

Abstract The binding of glucocorticoids to the type II or glucocorticoid receptor (GR) is known to play a role in memory consolidation and long-term memory. The present series of studies investigated the locus for GR effects on learning and memory of contextual fear conditioning. The GR antagonist RU 38486 was administered peripherally (10, 20, or 30 mg/kg/ml), as well as centrally into the lateral ventricle (75 or 150 ng/2 μL), basolateral amygdala (BLA; 0.3, 3, or 30 ng/0.2 μL), dorsal hippocampus (DH; 30 ng/μL) or ventral hippocampus (VH; 30 ng/μL) prior to contextual fear conditioning. Peripheral administration of RU 38486 did not affect fear-related levels of freezing immediately following a footshock or in a long-term memory test 24 h later. However, administration into the lateral ventricle, BLA, or VH decreased freezing in a 24 h retention test, while leaving post-shock levels of freezing intact. Both post-shock and retention levels of freezing were unaffected in rats that received RU 38486 in the DH compared to vehicle controls; however, vehicle rats also displayed low levels of freezing during retention. The data indicate that GR activation within the BLA and VH is important for the establishment of long-term memory for contextual fear conditioning.
Human neuroblastoma: Glial induced morphological differentiation

Rat C-6 glioma cells release a factor into culture medium which induces morphological differentiation in the IMR-32 human neuroblastoma cell line. The time course of differentiation and the effects on cell growth differ from those observed in mouse neuroblastoma cells. The effects of other cell lines and the relationship of differentiation to cell growth are discussed.
Post-translational processing reactions involved in the biosynthesis of lysosomal α-N-acetylgalactosaminidase in cultured human fibroblasts☆

Abstract The synthesis and processing of α- N -acetylgalactosaminidase and its oligosaccharides were studied by metabolic labeling of human skin fibroblasts with [2- 3 H]mannose or 32 P i , immunoprecipitation of the enzyme, gel electrophoresis of the immunoprecipitates, and examination of the radioactive oligosaccharides recovered from protein bands excised from the gels. The data suggest that the enzyme was first synthesized as a M r = 65,000 precursor which was then processed to a mature M r = 48,000 enzyme; only the M r = 65,000 precursor was immunoprecipitated from the culture medium. The oligosaccharides were separated into two chromatographic species by Bio-Gel P-4 fractionation. The more retained species were determined to be high-mannose oligosaccharides containing 7 to 9 mannose residues. A portion of the more highly excluded oligosaccharides from the M r = 65,000 band was hydrolyzed by alkaline phosphatase, and the resulting oligosaccharides migrated with the same mobility as Man 8–9 GlcNAc. This alkaline phosphatase-sensitive peak could also be labeled with 32 P i . These observations indicate that α- N -acetylgalactosaminidase was synthesized as a higher molecular weight precursor which contained phosphorylated high-mannose oligosaccharides.
Perithecial development by Gibberella zeae: a light microscopy study

Gibberella zeae (anamorph Fusarium graminearum) is the causal agent of head blight, and foot and crown rots of wheat, corn, oats and barley. The developmental sequence of perithecia from homothalli...
The Therapeutic Use of Journaling With Adolescents

In this article, we discuss and provide an example of journaling in the context of counseling, focusing on its application with adolescents. A script to be read by the therapist is included with prompts for self-reflection and journaling by the client. The excerpts presented are the actual journal reflections taken from a teenager's journal. The proposed technique has been used with positive results with adolescents in a clinical setting. Additionally, we provide suggestions for expanding the concept of journaling to expressive artwork.
Geomorphic controls and transition zones in the lower Sabine River

Instream flow science and management requires identification of characteristic hydrological, ecological, and geomorphological attributes of stream reaches. This study approaches this problem by identifying geomorphic transition zones along the lower Sabine River, Texas and Louisiana. Boundaries were delineated along the lower Sabine River valley based on surficial geology, valley width, valley confinement, network characteristics (divergent versus convergent), sinuousity, slope, paleomeanders, and point bars. The coincidence of multiple boundaries reveals five key transition zones separating six reaches of distinct hydrological and geomorphological characteristics. Geologic controls and gross valley morphology play a major role as geomorphic controls, as does an upstream-to-downstream gradient in the importance of pulsed dam releases, and a down-to-upstream gradient in coastal backwater effects. Geomorphic history, both in the sense of the legacy of Quaternary sea level changes, and the effects of specific events such as avulsions and captures, are also critical. The transition zones delineate reaches with distinct hydrological characteristics in terms of the relative importance of dam releases and coastal backwater effects, single versus multi-channel flow patterns, frequency of overbank flow, and channel-floodplain connectivity. The transitional areas also represent sensitive zones which can be expected to be bellwethers in terms of responses to future environmental changes. Copyright © 2007 John Wiley & Sons, Ltd.
Simple method for the estimation of absorption rate constant(ka) after oral administration.

This article describes a simple method for the estimation of absorption rate constant (ka ) after oral administration and compares the proposed method with some of the existing methods. The proposed method is based on a previous work of Urso and Aarons known as the regression method of truncated areas for the estimation of absolute bioavailability for drugs with a long elimination half-life. The following equation was used to estimate ka : Y(t) = ka. F - ka. X(t). Simple linear regression of Y(t) on X(t) results in a straight line with a slope of -ka, intercept on y-axis of ka F, and abscissa intercept F (absolute bioavailability). Different sets of plasma concentration versus time data for a hypothetical drug were generated by simulation. The estimated ka from the proposed method was compared with the Wagner-Nelson, Loo-Riegelman, and statistical moments methods. The results of this study indicated that the proposed regression method performed satisfactorily for a hypothetical drug that follows a one-compartment or two-compartment model with short or long half-life when tested under variable conditions (different absorption and elimination rate constants). The regression method of truncated areas can be used for the accurate estimation of ka for both short and long half-life drugs.
A Rapidly Evolving Homeobox at the Site of a Hybrid Sterility Gene

The homeodomain is a DNA binding motif that is usually conserved among diverse taxa. Rapidly evolving homeodomains are thus of interest because their divergence may be associated with speciation. The exact site of the Odysseus (Ods) locus of hybrid male sterility in Drosophila contains such a homeobox gene. In the past half million years, this homeodomain has experienced more amino acid substitutions than it did in the preceding 700 million years; during this period, it has also evolved faster than other parts of the protein or even the introns. Such rapid sequence divergence is driven by positive selection and may contribute to reproductive isolation.
Heat flux concentration through polymeric thermal lenses

A significant contributor to energy inefficiency is the generation as well as the uneven dissipation of heat. Practical methods to adeptly channel heat flux (Q) would then have widespread applications to improved energy utilization and thermal energy management. It would be beneficial to engineer lens-like composite materials (graded in terms of length or thermal conductivity) with augmented attributes for heat control. Here, we propose and demonstrate polymeric composite based Q focusing lenses, architected through geometrical considerations. We indicate a five-fold enhancement of the Q, at the level of ∼2500 W/m2, enabled through such thermal lenses.
Registration of lung nodules using a semi-rigid model: method and preliminary results.

The tracking of lung nodules across computed tomography(CT) scans acquired at different times for the same patient is helpful for the determination of malignancy. We are developing a nodule registration system to facilitate this process. We propose to use a semi-rigid method that considers principal structures surrounding the nodule and allows relative movements among the structures. The proposed similarity metric, which evaluates both the image correlation and the degree of elastic deformation amongst the structures, is maximized by a two-layered optimization method, employing a simulated annealing framework. We tested our method by simulating five cases that represent physiological deformation as well as different nodule shape/size changes with time. Each case is made up of a source and target scan, where the source scan consists of a nodule-free patient CT volume into which we inserted ten simulated lung nodules, and the target scan is the result of applying a known, physiologically based nonrigid transformation to the nodule-free source scan, into which we inserted modified versions of the corresponding nodules at the same, known locations. Five different modification strategies were used, one for each of the five cases: (1) nodules maintain size and shape, (2) nodules disappear, (3) nodules shrink uniformly by a factor of 2, (4) nodules grow uniformly by a factor of 2, and (5) nodules grow nonuniformly. We also matched 97 real nodules in pairs of scans (acquired at different times) from 12 patients and compared our registration to a radiologist’s visual determination. In the simulation experiments, the mean absolute registration errors were 1.0 ± 0.8 mm (s.d.), 1.1 ± 0.7 mm (s.d.), 1.0 ± 0.7 mm (s.d.), 1.0 ± 0.6 mm (s.d.), and 1.1 ± 0.9 mm (s.d.) for the five cases, respectively. For the 97 nodule pairs in 12 patient scans, the mean absolute registration error was 1.4 ± 0.8 mm (s.d.).
Design of a Robotic Mobility System with a Modular Haptic Feedback Approach to Promote Socialization in Children

Self-initiated mobility is a causal factor in children’s development. Previous studies have demonstrated the effectiveness of our training methods in learning directional driving and navigation. The ultimate goal of mobility training is to enable children to be social, that is, to interact with their peers. A powered mobility device was developed that can localize itself, map the environment, plan an obstacle-free path to a goal, and ensure safety of a human driver. Combined with a positioning system, this system is able to apply a force field using a modular haptic feedback approach to train subjects to drive towards an object, a caregiver, a peer, or a group of peers. System feasibility was tested by designing a ‘ball chasing’ game. Results show that the system is promising in promoting socialization in children.
Correlation of Electronic Structure with Catalytic Activity: H2–D2 Exchange across CuxPd1–x Composition Space

The relationship between alloy catalyst activity and valence band electronic structure has been investigated experimentally across a broad, continuous span of CuxPd1–x composition space. CuxPd1–x composition spread alloy films (CSAFs) were used as catalyst libraries with a 100 channel microreactor to measure the H2–D2 exchange kinetics over a temperature range of 333–593 K at 100 discrete CuxPd1–x compositions spanning the range x = 0.30–0.97. The H2–D2 exchange activity exhibits a monotonic decrease over the composition range x = 0.30–0.97. A steady state, microkinetic model was used to estimate the energy barriers to dissociative H2 adsorption, ΔEads‡, and recombinative H2 desorption, ΔEdes‡, as functions of alloy composition, x. Their values fall in the ranges ΔEads‡(x) = 0.15 to 0.45 eV and ΔEdes‡(x) = 0.55–0.65 eV. Spatially resolved UV photoemission spectra were obtained from the CuxPd1–x CSAF and used to estimate the average energy of the filled states of the valence band as a function of alloy com...
UV photoelectron and quantum mechanical characterization of DNA and RNA bases: valence electronic structures of adenine, 1,9-dimethyl-guanine, 1-methylcytosine, thymine and uracil

Abstract HeI UV photoelectron spectra of adenine, 1,9-dimethylguanine, 1-methylcytosine, thymine and uracil have been interpreted with the aid of results from ab initio SCF-MO calculations employing a double zeta 4–31G basis set, and HAM/3 semiempirical calculations. Ionization potentials from results of the SCF-MO calculations have been obtained through the application of Koopmans' theorem. For cytosine and guanine, problems associated with the occurrence of more than one tautomeric form in the gas phase have been circumvented by examining methyl substituted derivatives of these bases. For adenine, 1,9-dimethylguanine, thymine and uracil the current assignments, based on the results of the 4–31G SCF and HAM/3 calculations, are essentially the same as those provided in earlier studies. For 1-methylcytosine, the results of the current calculations and recent findings concerning the tautomerism of cytosine in nonpolar environments has led to new assignments. The vertical ionization potentials of the first (π 1 ), second (π 2 ), third (π 3 ) and fourth (π 4 ) highest occupied π orbitals in adenine are 8.48, ≈9.6, ≈10.5, and 12.10 eV, respectively. The ionization potentials of the first through third (n 1 -n 3 ) lone-pair orbitals are ≈9.6, ≈10.5, and 11.39 eV. In 1,9-dimethylguanine, the π 1 , π 4 and π 5 orbitals have ionization potentials of 8.09, ≈11.0, and 12.31 eV, while the π 2 and π 3 orbitals have ionization potentials in the range between 9.3 and 10.2 eV. Values for the ionization potentials of the n 1 and n 2 orbitals lie in the range between 9.3 and 10.2 eV, and the value for the n 3 orbital is ≈11.0 eV. In 1-methylcytosine, the ionization potentials of the π 1 through π 4 orbitals are 8.65, ≈9.7, 11.53, and 12.40 eV; the values for the n 1 and n 2 orbitals lie in the range 9.5 to 10.0 eV. For uracil, the ordering of the ionization potentials is π 1 (9.59 eV), n 1 (10.11 eV), π 2 (10.56 eV), n 2 (11.16 eV), and π 3 (12.63 eV). In thymine, the energetic ordering of orbitals is the same as in uracil and the corresponding ionization potentials have values of 9.18, 10.03, 10.39, 10.82 and 12.27 eV. An examination of DNA and RNA alkylation patterns occurring in reactions with dimethyl-sulfate, methylmethanesulfonate and N -methyl- N -nitrosourea indicates that the reactivity of nucleotide bases towards methylating reagents increases as the base ionization potentials decrease.
A finite analog to the löwenheim-skolem theorem

The traditional model theory of first-order logic assumes that the interpretation of a formula can be given without reference to its deductive context. This paper investigates an interpretation which depends on a formula's location within a derivation. The key step is to drop the assumption that all quantified variables must have the same range and to require only that the ranges of variables in a derivation must be related in such way as to preserve the soundness of the inference rules. With each (consistent) derivation there is associated a “Buridan-Volpin (orBV) structure” [M, {r(x)}] which is simply a Tarski structureM for the language and a map giving the ranger(x) of each variablex in the derivation. IfLK* is (approximately) the classical sequent calculusLK of Gentzen from which the structural contraction rules have been dropped, then our main result reads: If a set of first-ordered formulas Γ has a Tarski modelM, then from any normal derivationD inLK* of Γ ⇒ Δ can be constructed aBV modelMD=[M, {r(x)}] of Γ where each ranger(x) is finite.
Co-factor specificity of plant alcohol dehydrogenase

Abstract Extracts of seventeen plant tissues show alcohol dehydrogenase activity in the presence of both NADH and NADPH. Using extracts of melon fruits, attempts have been made to separate these two activities by applying a range of chromatographic and electrophoretic techniques but these proved unsuccessful. Evidence from kinetic measurements involving assays of equimolar concentrations of the two co-factors suggests that in the enzyme from the melon there is but a single catalytic site which will accept either co-factor.
Bivalves of Lower Cretaceous Alisitos Formation, Baja California, Mexico: ABSTRACT

More than one hundred bivalve species are recognized in the thick, predominantly pyroclastic, northwestern Baja California section which includes rocks and fossil localities cited in the original description of the Alisitos formation. A majority of the species is new. Bivalves and associated fossils suggest an Aptian age for most and possibly for all of the section investigated. The environments of deposition were generally sublittoral, including widely distributed reefs of corals and pachydont pelecypods. Highest parts of the Alisitos formation in the type area were deposited in fresh water. End_of_Article - Last_Page 1768------------
Enzyme fractionation and simultaneous nucleic acid removal from crude cellular extracts by preformed gradient ion exchange gel filtration.

Abstract A crude cellular lysate (S30) can be fractionated on DEAE Sephadex A-25 gel into major classes including an excluded protein class. The protein class itself can be fractionated simultaneously by applying a salt gradient to the A-25 gel before applying sample. The procedure is rapid, that is, complete in one column liquid volume (or less) of column development. In addition, the fractionating conditions are very mild permitting very high recovery of input enzyme activity in a volume representing minimal dilution of the original sample.
Optimizing robust limit cycles for legged locomotion on unknown terrain

While legged animals are adept at traversing rough landscapes, it remains a very challenging task for a legged robot to negotiate unknown terrain. Control systems for legged robots are plagued by dynamic constraints from underactuation, actuator power limits, and frictional ground contact; rather than relying purely on disturbance rejection, considerable advantage can be obtained by planning nominal trajectories which are more easily stabilized. In this paper, we present an approach for designing nominal periodic trajectories for legged robots that maximize a measure of robustness against uncertainty in the geometry of the terrain. We propose a direct collocation method which solves simultaneously for a nominal periodic control input, for many possible one-step solution trajectories (using ground profiles drawn from a distribution over terrain), and for the periodic solution to a jump Riccati equation which provides an expected infinite-horizon cost-to-go for each of these samples. We demonstrate that this trajectory optimization scheme can recover the known deadbeat open-loop control solution for the Spring Loaded Inverted Pendulum (SLIP) on unknown terrain. Moreover, we demonstrate that it generalizes to other models like the bipedal compass gait walker, resulting in a dramatic increase in the number of steps taken over moderate terrain when compared against a limit cycle optimized for efficiency only.
Exploring Alternative Individualized Treatment Strategies in Colorectal Cancer

Colorectal cancer (CRC) is the third most commonly diagnosed cancer in men and women in the United States, with a predicted 154,000 new cases this year. For > 40 years, 5-fluorouracil (5-FU) has remained the central agent in therapeutic regimens used in the treatment of CRC, with single-agent response rates (RRs) of 20%-25% in advancedstage disease. The past decade has witnessed the introduction of newer agents, such as the DNA-damaging agents oxaliplatin and irinotecan, which when used in combination with 5-FU, have dramatically increased RRs to 40%-50% in advanced disease and improved overall survival. The development of monoclonal antibodies targeting the epidermal growth factor receptor or vascular endothelial growth factor have now demonstrated additional clinical benefit for patients with metastatic disease, and the clinical development of these agents continues to progress. However, many patients will die, and a significant proportion will experience severe chemotherapy-induced toxicities, while deriving little or no benefit. Global efforts are currently under way to identify reliable and validated cassettes of markers with the ability to predict response and toxicity from a chemotherapeutic regimen. In addition, the ability to accurately predict patients with early-stage disease at high risk of recurrence will enable the appropriate administration of adjuvant therapy. The emerging cancer stem cell hypothesis continues to gain momentum with ongoing research, suggesting this might become one of the prime targets for future therapy. Together, these approaches are spearheading a paradigm shift toward individualized treatment strategies in CRC treatment.
GROWTH AND DEVELOPMENT OF SPECIES AND HYBRIDS OF POA UNDER CONTROLLED TEMPERATURES

A PROGRAM WAS INITIATED in 1943 by the Department of Plant Biology of the C,arnegie Institution for the study of various species and ecologic races of Poa and Poa hybrids in connection with their possible use as range grasses. One sector of this program is concerned with the problem of determining which factors are responsible for the successful growth -and survival of these plants in different kinds of environment. Genetic differences among species, clim,atic races, and individuals of the same species are strikingly evident in Poa. Moreover, the genus has a complex chromosomal structure based on several levels of polyploidy, and many of its species reproduce primarily by apomixis (cf. Akerberg, 1942; Clausen et al., 1947; Nygren, 1950). Although the genetic and cytologic framework of Poa is complex, reasonably well-defined taxonomic species have evolved. Some of these contrast markedly from each other in morphology, in natural distribution, and in their ability to grow in different kinds of environment. By testing species, strains, and interspecific hybrids of Poa in field plantings in contrasting climates in North America -and in Europe, it has been found that their relative performance varies widely. Very little is known concerning the genetically-controlled physiological characteristics that determine growth and development in various environments. A logical step in analyzing these char,acteristics is to study the comparative growth of selected forms under controlled conditions with but a single known external variable. With the completion of the Earhart Laboratory at the California Institute of Technology -at Pasadena in June, 1949, the opportunity to study the growth of plants under controlled environmental conditions on a fairly large scale was for the first time made possible. Through the invitation of its director, Dr. F. W. Went, the writer was privileged during 1950 to conduct the present study in this laboratory. The experiments here reported were limited to the investigation of the effects of various combinations of day and night temperatures on the growth and development of clones of key individuals of Poa which were also at the same time being grown under many contrasting field conditions. For a brief description of the Earhart Laboratory, the reader is referred to Went (1950).
SU-E-T-583: Optimizing the MLC Model Parameters for IMRT in the RayStation Treatment Planning System

Purpose: To optimize the MLC model parameters for IMRT in the RayStation v.4.0 planning system and for a Varian C-series Linac with a 120-leaf Millennium MLC. Methods: The RayStation treatment planning system models rounded leaf-end MLC with the following parameters: average transmission, leaf-tip width, tongue-and-groove, and position offset. The position offset was provided by Varian. The leaf-tip width was iteratively evaluated by comparing computed and measured transverse dose profiles of MLC-defined fields at dmax in water. The profile comparison was also used to verify the MLC position offset. The transmission factor and leaf tongue width were derived iteratively by optimizing five clinical patient IMRT QA Results: brain, lung, pancreas, head-and-neck (HN), and prostate. The HN and prostate cases involved splitting fields. Verifications were performed with Mapcheck2 measurements and Monte Carlo calculations. Finally, the MLC model was validated using five test IMRT cases from the AAPM TG119 report. Absolute gamma analyses (3mm/3% and 2mm/2%) were applied. In addition, computed output factors for MLC-defined small fields (2×2, 3×3, 4×4, 6×6cm) of both 6MV and 18MV were compared to those measured by the Radiological Physics Center (RPC). Results: Both 6MV and 18MV models were determined to have the same MLC parameters: 2.5% transmission,more » tongue-and-groove 0.05cm, and leaftip 0.3cm. IMRT QA analysis for five cases in TG119 resulted in a 100% passing rate with 3mm/3% gamma analysis for 6MV, and >97.5% for 18MV. With 2mm/2% gamma analysis, the passing rate was >94.6% for 6MV and >90.9% for 18MV. The difference between computed output factors in RayStation and RPC measurements was less than 2% for all MLCdefined fields, which meets the RPC's acceptance criterion. Conclusion: The rounded leaf-end MLC model in RayStation 4.0 planning system was verified and IMRT commissioning was clinically acceptable. The IMRT commissioning was well validated using guidance from the AAPMTG119 protocol.« less