cssi/SciSciGPT-SciSciNet huggingface dataset:
MUC1 is a substrate for γ-secretase

Understanding the underlying mechanisms by which a normal cell avoids the oncogenic potential of MUC1 signaling requires further definition of the pathways by which the MUC1 cytoplasmic tail is processed in both normal and tumor-derived cells. In the present study we describe the processing pathway initiated by TACE/ADAM17 cleavage of MUC1. Utilizing the human uterine epithelial cell line, HES, derived from normal endometrium, we show that endogenous full length MUC1 undergoes regulated intramembranous proteolysis mediated by presenillin-dependent gamma-secretase. Cytokine-stimulated HES cells exposed to gamma-secretase inhibitors accumulated a membrane-associated 15 kDa fragment of the MUC1 C-terminal subunit (CTF15). Inhibitors of TACE/ADAM17-mediated shedding inhibited accumulation of MUC1-CTF15 and MUC1 ectodomain release to a similar extent consistent with MUC1-CTF15 being a product of TACE/ADAM17 action. Reduction of catalytically active gamma-secretase complex by nicastrin siRNA treatment also resulted in CTF15 accumulation. Furthermore, mature nicastrin, the substrate receptor for gamma-secretase, co-immunoprecipitated with CTF15 in the presence of gamma-secretase inhibitors indicating the formation of CTF15: nicastrin complexes. MUC1-CTF15 accumulation in response to gamma-secretase inhibition was demonstrated in both normal and tumor-derived cells from humans and mice indicating that this processing pathway exists in many cell contexts. We did not detect products of MUC1 cleavage by gamma-secretase in the presence of various proteasomal inhibitors indicating that subsequent degradation is either non-proteasomal or extremely efficient. We suggest that this efficient pathway attenuates potential signaling mediated by cytoplasmic tail fragments.
The relative role of vaccines and drugs in control of human virus diseases

Abstract At present there are too few virus control agents of any kind to pose serious problems of choice between alternative methods of treatment; but, even when the ranges of both vaccines and drugs have been expanded to their full foreseeable scope, the occasions will be rare when vaccines and drugs will offer reasonable alternatives to each other. These is litte overlap between the two kinds of control agent either in the stage of infection when the agent may be effective or in the kind of agent which may be responsive. The reader of this series will have available to him other detailed descriptions of each class of antiviral drug, but it may be helpful to outline here the different classes of immunizing agents before we attempt to compare their roles with those of the drugs. A third distinct of virus control agent is interferon and interferon inducers. This is the subject of other papers in the seriesand will not be covered here.
Generalized Adjoint for Physical Processes with Parameterized Discontinuities. Part IV: Problems in Time Discretization.

Abstract It is shown analytically and graphically that when parameterized on/off switches are triggered at discrete time levels by a threshold condition in a numerical model, the model solution is not continuously dependent on the initial state. Consequently, the response function and costfunction contain small zigzag discontinuities; their gradients contain delta functions and thus are not good approximations of the original continuous gradients. The problem is caused by the traditional time discretization and cannot be solved by the conventional treatment of on/off switches. To solve the problem, the traditional time discretization is modified with the switch time determined by interpolation as a continuous function of the initial state. With this modification, the response function and costfunction become continuous in the space of the initial state and their gradients can be accurately computed by the generalized adjoint.
Giant pools of DNA precursors in sea urchin eggs

Abstract Pools of deoxyribonucleoside 5′ triphosphates were measured in eggs of the sea urchin, Strongylocentrotus purpuratus , both before and early after fertilization. The pools in unfertilized eggs are very large, amounting to between one and seven diploid nuclear equivalent units/egg. These high levels are maintained, with some fluctuations, for more than 2 h after fertilization, even in the presence of inhibitors of deoxynucleotide synthesis. This points to the existence of a large reservoir of dNTP precursors in the egg, as had been inferred from earlier studies. Exogenous radiolabeled DNA precursors, notably 3 H-thymidine, are routinely used to monitor DNA synthesis in sea urchins and other organisms. Because of the giant endogenous precursor pools and their fluctuations, plus previously described changes in deoxynucleoside transport and phosphorylation after fertilization, the relationship between thymidine labeling and DNA synthesis requires clarification. At high thymidine concentrations, as shown herein, nearly all of the DNA thymine residues appear to be derived from exogenous thymidine during the first S phase. The mechanism of this preferential utilization is not known.
Chinese Migration and Settlement in a Thai Village

This paper uses data from a 1-year field study of demographic history and behavior in a Thai village (Baan Naku) in the Central Plains to illustrate the considerable impact Chinese migrants had on even rural remote villages. The 1976 field study of Baan Naku used participant/observation cultural informants in depth interviews case histories and reconstruction of family genealogies. Nearly 1/3 of previous and present inhabitants of the village were wholly or partly Chinese. For some Chinese immigrants residence in Baan Naku was a stepping stone on the way to greater success; for others it was a final destination after previous failures. The author illustrates this with 2 case histories. The most remarkable aspect of Chinese migration to Thailand is the apparent degree to which Chinese migrants and their descendants have been assimilated in to Thai culture; however significant differences remain. While Thai villages often refer to Chinese-Thai neighbors derogatorily they generally admire Thai-Chinese offspring. To a limited extent some characteristics of the extended family structure have survived among Naku villagers of Chinese descent; for example the Thai-Chinese keep in better contact among each other than the purely Thai villagers. Many Thai-Chinese villagers believed that marriages occurred at significantly younger ages in their Chinese homeland than in Thailand. In fact in 1929-1931 the singulate mean age for marriage for South China was 17.78. Comparable data from Baan Naku shows that mean age of marriage for surviving women in the 70 years and over cohort was 23.7. Chinese-Thai villagers differed from Thai villagers in 2 ways: 1) they had greater financial acumen and 2) they controlled their children more strictly especially with regard to marriage. Because of brideprice payment requirements Thai-Chinese villagers delayed marriage during the economic difficulties of World War II. Thus despite rapid assimilation into Thai culture differences remain between the Chinese and Thais.
Multiple subfailures characterize blunt aortic injury.

BACKGROUND: Blunt aortic injuries result from rapid deceleration of the thorax as may occur during automotive impacts and falls from extreme heights. Pathological findings can range from failure of specific vessel layers to immediate vessel wall rupture. The purpose of this investigation was to determine the sequence of local structural events that may lead to aortic wall disruption. METHODS: Fourteen porcine aorta specimens were opened to expose the intima and longitudinally distracted until rupture. Longitudinal mechanics were quantified and subfailures were identified. Histology was used to examine internal layer subfailure. RESULTS: Videography demonstrated that subfailures propagated into complete vessel wall rupture. Subfailures occurred before complete vessel rupture in 93% of specimens. Intimal and medial subfailures were present at 74% of the stress and 82% of the strain to rupture. Multiple subfailures were evident in 79% of specimens. CONCLUSION: Present results supported the clinical theory that nonimmediate death as a result of blunt aortic injury is commonly caused by propagation of lesser lesions, initiating on the intimal layer, into complete vessel rupture including the adventitial layer. This finding, along with histologic evidence of subfailure pathological findings, confirms the presence of an acute window during which recognition and initiation of permissive hypotension may be lifesaving. Language: en
Clathrin-mediated endocytosis of the beta-adrenergic receptor is regulated by phosphorylation/dephosphorylation of beta-arrestin1.

β-Arrestins serve a dual regulatory role in the life cycle of G protein-coupled receptors such as the β2-adrenergic receptor. First, they mediate rapid desensitization by binding to G protein-coupled receptor kinase-phosphorylated receptors. Second, they target the receptors for internalization into endosomal vesicles, wherein receptor dephosphorylation and resensitization occur. Here we report that phosphorylation of a carboxyl-terminal serine (Ser-412) in β-arrestin1 regulates its endocytotic but not its desensitization function. Cytoplasmic β-arrestin1 is constitutively phosphorylated and is recruited to the plasma membrane by agonist stimulation of the receptors. At the plasma membrane, β-arrestin1 is rapidly dephosphorylated, a process that is required for its clathrin binding and receptor endocytosis but not for its receptor binding and desensitization. Once internalized, β-arrestin1 is rephosphorylated. Thus, as with the classical endocytic adaptor protein complex AP2, β-arrestin1 functions as a clathrin adaptor in receptor endocytosis which is regulated by dephosphorylation at the plasma membrane.
Pathogenesis, clinic, and treatment of ganglion.

In clarification of various theories on the pathogenesis of the ganglion, histopathologic examinations indicate that the ganglion develops from connective tissue by myxoid degeneration and disintegration of collagen fibers. Increasing amounts of mucinous fluid accumulate by the progressive liquefaction of collagen fibers and are surrounded by densifying collagen bundles which form a delimiting capsule. In view of the inadequacy of conservative treatment and the shortcomings of excision, the subcutaneous (s.c.) discission of the ganglion with a tenotome is recommended. Of 184 patients treated this way, 151 displayed full healing, six underwent a successful repetition of the procedure, nine underwent an excision of the recurrent ganglion, and 18 rejected further treatment.
Asymptotic analysis of the effect of arrival model uncertainties in some optimal routing problems

We study the effect of arrival model uncertainties on the optimal routing in a system of parallel queues. For exponential service time distributions and Bernoulli routing, the optimal mean system delay generally depends on the interarrival time distribution. Any error in modeling the arriving process will cause a model-based optimal routing algorithm to produce a mean system delay higher than the true optimum. In this paper, we present an asymptotic analysis of the behavior of this error under heavy traffic conditions for a general renewal arrival process. An asymptotic analysis of the error in optimal mean delay due to uncertainties in the service time distribution for Poisson arrivals was reported in Ref. 6, where it was shown that, when the first moment of the service time distribution is known, this error in performance vanishes asymptotically as the traffic load approaches the system capacity. In contrast, this paper establishes the somewhat surprising result that, when only the first moment of the arrival distribution is known, the error in optimal mean delay due to uncertainties in the arrival model is unbounded as the traffic approaches the system capacity. However, when both first and second moments are known, the error vanishes asymptotically. Numerical examples corroborating the theoretical results are also presented.
An Electronic Circuit for Trickle Charge Harvesting From Littoral Microbial Fuel Cells

In this paper, the design of an electronic circuit for harvesting energy trickling from benthic sources and the long-term performance in powering sensors and devices in a littoral tidal basin are considered. The process has to contend with the randomness, diurnal variations, and low levels and voltages in available energy compared to what is required by oceanographic sensors. The system has two components: a circuit for conditioning the power and a large area electrode array in a littoral basin. The circuit has two stages and is able to overcome the leaks in capacitors used to store the power; the energy is stored first in a small capacitor and then in a large one so that voltages compatible with sensors are produced. The footprint of the anode is 10 m2 and is inserted into the sediment and the cathode resides in the salt water above the sediment. Several different sensors and actuators have been autonomously powered by the stored energy (4.2 kJ at 12 V). A beacon and an underwater acoustic sensor (5 h of activation of combined hydrophone and three-axis accelerometer sensors, every 40 h; duty cycle has been doubled with recent improvements) have been powered over one to two months. Also, in-water propulsion (for 165 s at a time) of a 25-W biorobotic flapping fin propulsor has been achieved. The system is suitable primarily for powering sensors. It has been operated for more than three years at useful duty cycles, indicating sustainability for autonomous usage.
A Collaborative Workflow for the Digitization of Unique Materials

This paper examines the experience of one institution, the University of Maryland Libraries, as it made organizational efforts to harness existing workflows and to capture digitization done in the course of responding to patron requests. By examining the way this organization adjusted its existing workflows to put in place more systematic methods for digital capture of unique collections, the authors hope to provide insight into the benefits and pitfalls of one model for scaling up digitization.
Reflections on Scientific and Religious Metaphor

The importance of scientific conflicts for theology and philosophy is difficult to judge. In many disputes of significance, prominent scientists can be found on both sides. Profound philosophical and religious implications are sometimes said to be implied by the new theory as well. This article examines the dispute over natural selection between Richard Dawkins and Stephen Jay Gould as a contemporary instance of such a conflict. While both claim that profoundphilosophical conclusions flow from their own alternative account of evolution, I suggest that the implication is not as great as is claimed and that the alleged implications have as much to do with their own perceptions of theology as with the actual theories themselves. Nevertheless, evolutionary theory is not irrelevant for theology. Theologians should be aware of the possible implications of evolutionary theory and at the same time the extent and limits of such implications.
The effect of medetomidine and its antagonism with atipamezole on stress-related hormones, metabolites, physiologic responses, sedation, and analgesia in goats.

Six 3-year-old goats (three males and three females) weighing 60.0 ± 18 kg (mean ± SD) were used to investigate the effect of medetomidine (MED; 20 µg kg−1 IV) and its antagonism with atipamezole (ATI; 100 µg kg−1 IV) on physiologic responses (heart rate (HR; beats minute−1), respiratory rate (RR; breaths minute−1), electrocardiogram (ECG), rectal temperature (T; °C), blood pressure (oscillometric; mm Hg), sedation (SED), posture (REC), analgesia (ALG), and stress-related hormonal and metabolic responses (epinephrine and norepinephrine (high performance liquid chromatography with electrochemical detection), cortisol (COR; µg dL−1; radioimmunoassay), glucose (GLU; mg mL−1; enzymatic colorimetric assay), and free fatty acids (modified enzymatic colorimetric assay)); each goat received ATI or SAL in random order separated by 1 week. Jugular catheters were placed for drug administration and blood sampling (10–12 mL sample−1) using a lidocaine skin block (20 mg) 2 hours prior to beginning of each trial; during this trial, goats breathed room air. Physiologic parameters were measured, SED, REC, and ALG were scored, and blood samples were collected from jugular catheters at baseline (time = −30 minutes), 5 minutes post-MED administration (time = −25 minutes), 25 minute post-MED administration and immediately prior to antagonism (time = 0 minute), and at 5, 30, 60, and 120 minutes after administering ATI or SAL. ALG was tested by clamping the withers and metacarpus with hoof testers fitted with a force transducer to measure applied isometric force (lb) (a technique used previously in goats to evaluate analgesia). Continuous variables were analyzed by Repeated Measures analysis of variance (anova); categorical data were analyzed using a Friedman Repeated Measures anova on ranks. A p-value of <0.05 was considered significant. If a significant difference was found, a Dunnett's pair-wise comparison of means was conducted. Differences between ATI and SAL were examined at 5, 30, 60, and 120 minutes using a paired t-test with a Bonferroni correction. Administration of MED resulted in a decrease in T (38.7 ± 0.3 to 34.5 ± 0.4 °C), HR (78 ± 19 to 55 ± 9), and RR (31 ± 12 to 14 ± 5) over time; an increase in mean arterial blood pressure (90 ± 19 to 132 ± 23), COR (0.254 ± 0.125 to 4.327 ± 1.233), and GLU (82.0 ± 13.2 to 255.9 ± 38.9); and changes in SED (alert to marked sedation), REC (standing to recumbent), and ALG (metacarpus = 5 ± 2 to 14 ± 0; withers = 3 ± 2 to 14 ± 0). GLU was 62–70% higher at 60 and 120 minutes and COR was 336% higher after SAL than after ATI at 120 minutes; at 30, 60, and 120 minutes, T was 4–10% higher after ATI than SAL. There were no other significant differences. REC, SED, and ALG were antagonized after ATI. ATI did not antagonize the effect of MED on HR, RR, or MAP, but stabilized T and antagonized the increase in GLU and COR.
Unconventional superspeed computer systems

As machine systems grow in complexity to provide ever higher quality and quantity of service, increasing attention has to be paid to aspects of computing which are not the requirements for problem solving, but rather demands imposed by the handling technique prescribed for earlier machines!
Luteinizing hormone and testosterone concentrations in plasma of bull calves treated with gonadotropin releasing hormone.

Twelve bull calves, 2 to 24 days of age, were assigned to two groups of six calves and administered a single 50 μg intramuscular injection of gonadotropin releasing hormone. Bull calves in group 1 were 2 to 5 days of age (mean 3.0 days), and bull calves in group 2 were 10 to 24 days of age (mean 17.1 days). Blood plasma for radioimmunoassay of luteinizing hormone and testosterone was collected at .5-h intervals for 3-h and at 4- and 6-h following treatment. With increasing age, preinjection luteinizing hormone concentrations in plasma decreased while preinjection testosterone concentrations increased. Mean preinjection luteinizing hormone concentrations for group 1 (1.01 ± .07 ng/ml; mean ± standard error) were higher than for group 2 (.61 ± .12 ng/ml). Preinjection luteinizing hormone and testosterone concentrations were correlated −.63. Following treatment, luteinizing hormone increased with mean peak concentrations of 7.28 ± .74 and 6.95 ± 1.79 ng/ml for groups 1 and 2. Peak testosterone response following gonadotropin releasing hormone was higher for group 2 than 1 (1077 ± 253 versus 436 ± 116pg/ml).
Developmentally-induced Mll1 loss reveals defects in postnatal haematopoiesis

The mixed lineage leukemia (MLL) gene is disrupted by chromosomal translocations in acute leukemia, producing a fusion oncogene with altered properties relative to the wild-type gene. Murine loss-of-function studies have shown an essential role for Mll in developing the haematopoietic system, yet studies using different conditional knockout models have yielded conflicting results regarding the requirement for Mll during adult steady-state haematopoiesis. In this study, we used a loxP-flanked Mll allele (Mll(F)) and a developmentally regulated, haematopoietic-specific VavCre transgene to reassess the consequences of Mll loss in the haematopoietic lineage, without the need for inducers of Cre recombinase. We show that VavCre;Mll mutants exhibit phenotypically normal fetal haematopoiesis, but rarely survive past 3 weeks of age. Surviving animals are anemic, thrombocytopenic and exhibit a significant reduction in bone marrow haematopoietic stem/progenitor populations, consistent with our previous findings using the inducible Mx1Cre transgene. Furthermore, the analysis of VavCre mutants revealed additional defects in B-lymphopoiesis that could not be assessed using Mx1Cre-mediated Mll deletion. Collectively, these data support the conclusion that Mll has an essential role in sustaining postnatal haematopoiesis.
Lack of induction of substance P gene expression by hypoxia and absence of neurokinin 1-receptor mRNAs in the rat carotid body

Peripheral chemoreceptors are commonly thought to respond to hypoxia by releasing neurotransmitters from the type 1 cells of the carotid body; these molecules then bind to post-synaptic receptors on the carotid sinus nerve. The tachykinin substance P (SP) may act as an important neurotransmitter/neuromodulator in hypoxic chemotransmission in peripheral arterial chemoreceptors. In order to elucidate the role of SP in modulating hypoxic chemotransmission, we have used quantitative in situ hybridization histochemistry, to determine the effect of hypoxia on SP gene induction, and the localization of neurokinin 1 (NK-1) receptor mRNA in the carotid body and petrosal ganglia complex in rats at 21 days post-natal age. For comparison, we also determined: (1) the effect of hypoxia on tyrosine hydroxylase (TH) gene induction and (2) the localization of the mRNA encoding the D2-dopamine receptor. SP mRNA was not detected in the rat carotid body during normoxia and its expression was not induced after a 1 h of exposure to hypoxia (10% O2/90% N2), a stimulus that was sufficient to cause a significant increase (P<0.01) in TH mRNA levels in the carotid body. Both SP and TH mRNAs were abundantly expressed in multiple cells in the petrosal and the jugular ganglia. However, these mRNAs were not co-localized and SP and TH mRNA levels were not affected by hypoxia in these ganglia. Although D2-dopamine receptor mRNA was abundantly expressed in the rat carotid body, we found no evidence of NK-1 receptor mRNA in the carotid body. In contrast, both NK-1 receptor mRNA and D2-dopamine receptor mRNA were present in petrosal ganglion cells. In the rat, SP does not appear to modulate hypoxic chemotransmission by being made in and released from type 1 cells in the carotid body, and neither does SP modulate the activity of type 1 cells by binding to NK-1 receptors on these cells.
Angular distribution of the photoelectron spectrum of CO2, COS, CS2, N2O, H2O, and H2S

Abstract The photoelectron spectra of the triatomic molecules CO 2 , COS, CS 2 , N 2 O, H 2 O, and H 2 S have been measured as a function of the angle θ between the direction of the incoming photon and outgoing photoelectron. The photoelectron spectra have been measured with a double-focusing electrostatic electron spectrometer to which has been attached a chamber containing a gas discharge lamp that can be freely rotated. (The photon source used was the 21.22 eV He I resonance line). From the dependence of intensity as a function of θ the angular parameter β was determined for each ionization band observed in the photoelectron spectra. A correlation was noted between the values of β and the molecular orbitals relative to the contributions of oxygen and sulfur atomic orbitals. Individual β values were also obtained for most of the vibrational bands seen in the photoelectron spectra. In most cases the vibrational structure showed little or no change in the angular parameter for a given electronic state. In certain cases, however, such as the fourth ionization band in CS 2 , CO 2 , and COS, rather sizeable changes in β were observed for the different vibrational bands.
Purification of leaf nucleotides and nucleosides on insoluble polyvinylpyrrolidone.

Abstract Of the 19 nucleotides and nucleosides tested, all were eluted by 1 m M HCl in less than 60 ml from 2 × 6-cm columns of Polyclar AT (an insoluble polyvinylpyrrolidone). Recoveries were good and, with the possible exceptions of ADPG and UDPG, the presence of cotton leaf extract did not decrease recovery of known nucleotides and nucleosides. Passing leaf extracts through Polyclar AT removed most, but not all, of the uv-absorbing impurities that interfere with quantitation of nucleotides and nucleosides. The optimum pH for purification of HClO 4 extracts from leaves of alfalfa, cotton, grape, and orange appeared to be between 2.0 and 3.0. In this pH range Polyclar AT removed from 59 to 91% of the substances in leaf extracts that absorbed at 230 nm and from 93 to 97% of the substances that absorbed at 320 nm. Extraction of leaf extract with isoamyl alcohol was relatively ineffective and extraction with ether was almost completely ineffective in removing uv-absorbing impurities. Because nucleotides and nucleosides quickly pass through a short column of Polyclar AT at pH 3.0 while plant phenols are retained, this procedure provides a simple and rapid method for bulk purification of leaf extracts prior to chromatography and assay of nucleotides and nucleosides.
17 Clinical and Experimental Considerations in Facial Bone Biology: Growth, Remodeling and Repair

Prenatal and postnatal environmental factors influence the growth of bone, which is a dynamic, sensitive, everchanging tissue. Whereas growth is active only during early life, remodeling and repair remain active throughout life. In this paper, the biology of facial bones in terms of growth, remodeling, and repair is correlated with the development of facial deformities, and some principles are outlined which could aid in the surgical approach to malocclusion problems.
Recovery of spores of Bacillus stearothermophilus from thermal injury.

Bacillus stearothermophilus grown in nutrient broth produced a product which promoted recovery from thermal injury of its spores. This phenomenon was observed with nutrient agar as the plating medium but not with a medium composed of Trypticase, Phytone, dextrose and phosphate (TPDP). Recovery of injured spores was greatest in such a medium if it contained starch or charcoal. Trypticase soy agar and dextrose tryptone agar were markedly inferior to TPDP medium.
Parallel Computation of Microscale Heat Conduction in Thin Films

Results are presented from the numerical simulation of 2-D heat conduction in homogeneous as well as multi-layered thin lms of rectangular geometry. The Boltzmann Transport equation, in both its frequency integrated form as well as the frequency inclusive form with spatially and frequency dependent relaxation time, is considered for the numerical solution. Parallelization issues associated with the two approaches are discussed and an appropriate strategy with optimal parallel architecture parameters are suggested for each case. The numerical solution results address the eects of the lm thickness, grain boundary scattering and interfacial boundary conditions on the internal temperature distribution of multi- layered thin lms comprised of various materials. Background
Polymer model of cancer cell adhesion to glycosaminoglycan substrates using the radius of gyration

The hypothesis that the adhesion of whole cancer cells to glycosaminoglycan (GAG) substrates is a function of polysaccharide radius of gyration is presented. We use a worm-like chain (WLC) polymer model describing the global structure of the GAGs that will take into account the charge distribution and contour length of the polysaccharide implicitly in its radius of gyration to relate these parameters to cell adhesion. Specifically, we present measurements of the in vitro adhesion of cancer cells to isolated and individualized GAG substrates. We find that adhesion of the cells has a linear response with the radius of gyration and is essentially controlled by the charge per dimer. This dominating mechanism is not eliminated when the cells are subjected to resuspension in media with heparin. We then propose how these physical properties could be used to predict the preferred molecular structures of compounds for use as antimetastatic or antiinflammatory agents by comparing our results with known effective molecules. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Haptic externalization in a backwardly placed anterior chamber intraocular lens

Abstract A patient who had been asymptomatic following extracapsular cataract extraction with posterior capsule rupture and anterior chamber lens implantation presented is months postoperatively with iritis and erosion of the superior haptic through the site of the cataract wound. At the time of explantation, it was seen that the anterior chamber lens had been inserted in a backward manner with the anterior face of the lens placed posteriorly. The resultant leas vaulting placed the superior haptic in the same plane as the cataract wound. Whether the superior haptic had initially been incorporated in the surgical wound or had eroded through the eye wall from the anterior chamber, the backward placement of the anterior chamber lens likely played a role in the development of haptic externalization.
Chemical alteration of poly(vinyl fluoride) Tedlar® induced by exposure to vacuum ultraviolet radiation

Abstract In this study the chemical alteration of poly(vinyl fluoride) Tedlar® by vacuum ultraviolet radiation (VUV) (115–400 nm) has been examined using X-ray photoelectron spectroscopy (XPS). The initial F/C atom ratio of 0.34 decreases to 0.17 after a 2-h exposure. The F/C atom ratio is further reduced to a steady-state value of approximately 0.04 after a 24-h exposure. Similarly, the O/C atom ratio is reduced from 0.08 to 0.05 and then to 0.02 during these two exposures. As the F and O are removed by VUV exposure, the C concentration increases from 70.5 to 82.0 and then to 94.6 at.% thus forming a graphitic or amorphous carbon-like layer which erodes more slowly than the virgin Tedlar surface. Exposure of the VUV-damaged surface to O2 results in chemisorption of O, indicating that reactive sites are formed during the chemical erosion by VUV. Further exposure to VUV removes this chemisorbed oxygen but a subsequent exposure to air at atmospheric conditions causes a three-fold increase in O chemisorbed at the surface. Comparison of XPS data indicates that the mechanisms of chemical alteration by VUV radiation and hyperthermal (∼5 eV) atomic oxygen (AO) are similar.
Flexible manufacturing systems and the internal structure of the firm

Abstract We investigate the relationship between the internal structure of the firm and the extent of flexibility of its technology. We demonstrate that increased vertical separation within the firm as implied, for instance, by subcontracting or by additional vertical layers of management yields investment in a more flexible technology. In contrast, increased horizontal separation as implied by lack of cooperation among different (horizontal) divisions within the firm has ambiguous implications on flexibility. When divisions of the organization confront significantly different levels of uncertainty, horizontal separation enhances technological flexibility. Otherwise, when the extent of uncertainty confronting different divisions is comparable it is cooperation that yields greater flexibility of the technology. We show that the attributes of the technology selected by a given firm may depend upon the internal structure of its competitor if those attributes can be observed by the competing firm. In particular, the firm chooses a less flexible technology if its competitor is vertically separated rather than integrated.
Exploring structural effects of ketone catalysts on asymmetric epoxidation of olefins

Abstract Several ketone catalysts containing spiro ethers and lactones have been investigated for the asymmetric epoxidation of olefins. The results showed that substituents on the spiro ring of the ketone catalysts have profound effects on enantioselectivity. Results also suggested that the high enantioselectivities previously observed for conjugated cis-olefins with oxazolidinone containing ketones could be partially due to attractive interactions between the Rπ group of the olefin and the carbonyl group of the oxazolidinone. In addition, nonbonding interactions such as van der Waals forces and/or hydrophobic interactions between the olefin substituents and the nitrogen substituents of the oxazolidinone may also be involved in stereodifferentiation. The information gained provides additional understanding of factors important for ketone catalyzed epoxidations.
Third grade African American students' views of the nature of science

This study examined the nature of science (NOS) views of lower elementary grade level students, including their views of scientists. Participants were 23 third-grade African American students from two Midwest urban settings. A multiple instrument approach using an open-ended questionnaire, semi-structured interviews, a modified version of the traditional Draw-A-Scientist Test (DAST), and a simple photo eliciting activity, was employed. The study sought to capture not only the students' views of science and scientists, but also their views of themselves as users and producers of science. The findings suggest that the young African American children in this study hold very distinct and often unique views of what science is and how it operates. Included are traditional stereotypical views of scientists consistent with previous research. Additionally, participants expressed excitement and self-efficacy in describing their own relationship with science, in and outside of their formal classrooms. Implications for teaching and learning NOS as it relates to young children and children of color are discussed. © 2011 Wiley Periodicals, Inc. J Res Sci Teach 49: 1–37, 2012
Iris recognition using histogram analysis

Iris recognition is perhaps the most accurate means of personnel identification due to the uniqueness of the patterns contained in each iris. Most commercial iris recognition systems use a patented algorithm based on two-dimensional Gabor wavelets developed by Daugman. This paper describes an alternate means to identify individuals using images of their iris. Here, we simplify the process by using preprocessed one-dimensional histograms. The methodology in forming these histograms, how they are used in enrollment and identification and performance in terms of false positives and false negatives are presented.
Nanosecond optical parametric oscillator with 90° image rotation: design and performance

According to numerical models of nanosecond optical parametric oscillators, cavities with 90° image rotation can produce high-quality beams even if the Fresnel number of the cavity is large. We review the properties of such image-rotating cavities and present a method for designing them. The laboratory performance of one promising design is characterized, demonstrating its ability to produce high-quality beams with good efficiency.
Isoleucine needs of thirty- to forty-two-day-old female chickens: growth and carcass responses

Two experiments were conducted to evaluate Ile responses in female broilers. In experiment 1, dietary Ile was 0.42 or 0.72% total of diet. Diets were fed to 3 broiler strains: multipurpose Arbor Acres+, high-yield Ross 508, and high-yield Ross 708. In experiment 2, dietary Ile dose responses (0.42 to 0.82% total of diet in 0.08% increments) were evaluated. A corn-soybean meal control (0.70%) diet was used in experiment 2 (6 replications). No Ile x strain interactions occurred. Feeding broilers 0.42% Ile suppressed (P < 0.05) BW gain, feed intake, feed conversion, and breast and thigh yields. Arbor Acres+ strain had a higher BW gain and feed intake (P < 0.05) than the Ross 508 and 708 strains. Differences (P < 0.05) among strains were observed in breast and drumstick yields; Ross 708 broilers had increased breast and drumstick yields in comparison to birds from the Arbor Acres+ and Ross 508 strains. Birds fed surfeit Ile in the titration diets grew as well as (P < 0.05) the birds fed the control diet. Quadratic responses (P < 0.05; 95% of response) were obtained for BW gain (0.67%), feed intake (0.66%), feed conversion (0.68%), and breast meat yield (0.63%). The 30- to 42-d Ile need for female broilers is between 0.63 and 0.68% of total diet (0.59 to 0.64% digestible Ile).
ECOHYDROLOGICAL CONTROL OF DEEP DRAINAGE IN ARID AND SEMIARID REGIONS

The amount and spatial distribution of deep drainage (downward movement of water across the bottom of the root zone) and groundwater recharge affect the quantity and quality of increasingly limited groundwater in arid and semiarid regions. We synthesize research from the fields of ecology and hydrology to address the issue of deep drainage in arid and semiarid regions. We start with a recently developed hydrological model that accurately simulates soil water potential and geochemical profiles measured in thick (.50 m), unconsolidated vadose zones. Model results indicate that, since the climate change that marked the onset of the Holocene period 10 000-15 000 years ago, there has been no deep drainage in vegetated interdrainage areas and that continuous, relatively low ( ,21 MPa) soil water potentials have been maintained at depths of 2-3 m. A conceptual model con- sistent with these results proposes that the native, xeric-shrub-dominated, plant communities that gained dominance during the Holocene generated and maintained these conditions. We present three lines of ecological evidence that support the conceptual model. First, xeric shrubs have sufficiently deep rooting systems with low extraction limits to generate the modeled conditions. Second, the characteristic deep-rooted soil-plant systems store suffi- cient water to effectively buffer deep soil from climatic fluctuations in these dry environ- ments, allowing stable conditions to persist for long periods of time. And third, adaptations resulting in deep, low-extraction-limit rooting systems confer significant advantages to xeric shrubs in arid and semiarid environments. We then consider conditions in arid and semiarid regions in which the conceptual model may not apply, leading to the expectation that portions of many arid and semiarid watersheds supply some deep drainage. Further ecohy- drologic research is required to elucidate critical climatic and edaphic thresholds, evaluate the role of important physiological processes (such as hydraulic redistribution), and evaluate the role of deep roots in terms of carbon costs, nutrient uptake, and whole-plant devel-
NONLINEAR COUPLED SEISMIC SLIDING ANALYSIS OF EARTH STRUCTURES

Earthquake-induced sliding displacements of earth structures are generally evaluated using simplified sliding block analyses that do not accurately model the seismic response of the sliding mass nor the seismic forces along the slide plane. The decoupled approximation introduced to capture each of these effects separately is generally believed to be conservative. However, recent studies using linear viscoelastic sliding mass models have revealed instances where the decoupled approximation is unconservative. In this paper, a coupled analytical model that captures simultaneously the fully nonlinear response of the sliding mass (necessary for intense motions) and the nonlinear stick-slip sliding response along the slide plane is presented. The proposed sliding model is validated against shaking table experiments of deformable soil columns sliding down an inclined plane. The effect of sliding on the response of earth structures is evaluated, and comparisons are made between sliding displacements calculated us...
Coupled consolidation model for negative skin friction on piles in clay layers

Expansive soils swell on absorbing water and shrink on evaporation thereof. Because of this alternate swelling and shrinkage, civil engineering structures founded in them are severely damaged. For counteracting the problems of expansive soils, different innovative techniques were suggested. Stabilization of expansive clays with various additives has also met with considerable success. This paper presents, by comparison, the effect of lime and fly ash on free swell index (FSI), swell potential, swelling pressure, coefficient of consolidation, compression index, secondary consolidation characteristics and shear strength. Lime content was varied as 0%, 2%, 4% and 6% and fly ash content as 0%, 10% and 20%. A fly ash content of 20% showed significant reduction in swell potential, swelling pressure, compression index and secondary consolidation characteristics and resulted in increase in maximum dry density and shear strength. Swell potential and swelling pressure decreased with increase in lime content also. F...
Mellin transform solution for the static line-source excitation of a dielectric wedge

An integral transform analysis of the static scattering of the two-dimensional potential radiated by a line source in the vicinity of a penetrable wedge is presented. The Mellin transform is used to derive the exact static solution to Laplace's equation for the dielectric wedge, in the form of a modal series. The important dielectric edge condition behavior is explicitly contained in this analytic solution. >
Electrical parameters of projectile stun guns

Projectile stun guns have been developed as less-lethal devices that law enforcement officers can use to control potentially violent subjects, as an alternative to using firearms. These devices apply high voltage, low amperage, pulsatile electric shocks to the subject, which causes involuntary skeletal muscle contraction and renders the subject unable to further resist. In field use of these devices, the electric shock is often applied to the thorax, which raises the issue of cardiac safety of these devices. An important determinant of the cardiac safety of these devices is their electrical output. Here the outputs of three commercially available projectile stun guns were evaluated with a resistive load and in a human-sized animal model (a 72 kg pig).
A composite reference section for terminal proterozoic strata of southern Namibia.

Integrated sequence stratigraphic and chemostratigraphic data yield a framework for correlations of stratigraphic units in the terminal Proterozoic to Cambrian Witvlei and Nama Groups of Namibia. Coupled with precise U-Pb zircon age constraints, these correlations make it possible to construct a composite reference section for use in calibrating terminal Proterozoic chronostratigraphy. The Namibian reference section starts with two distinct glacial horizons and extends up to within 1 million years of the Proterozoic-Cambrian boundary. The two glacial horizons may represent each of two distinct Varanger-age glaciations better known from the North Atlantic region. From the higher of the two glacial horizons up, the composite stratigraphy preserves one of the thickest and most complete available records of carbon-isotope variability in post-Varanger terminal Proterozoic seawater. Four carbon-isotope chemostratigraphic intervals are recognized: (1) a postglacial negative δ^(13)C excursion (Npg interval); (2) a rising interval (Pr interval) of increasing positive delta 13 C values; (3) a falling interval (Pf interval) characterized by decreasing positive δ^(13)C and culminating in near zero or negative values; and (4) an interval of moderately positive, relatively invariant δ^(13)C values (I interval) that extends up to the unconformity that contains the Proterozoic-Cambrian boundary. Each of these chemostratigraphic intervals can be recognized in widely separated correlative sections around the world. By comparing sediment accumulation rate in the radiometrically calibrated Namibian stratigraphy with sediment accumulation rates in correlative sections in Arctic Canada and Oman, a maximum age of 564 Ma is estimated for the end of the younger Varanger glaciation, 25 m.y. younger than previous estimates.
Color display systems: The state of the art

This paper presents the basic dimensions and characteristics of the nine currently marketed self-contained color display systems that could conceivably be employed by psychologists for instruction and research in psychology. The systems all cost less than $10,000, with the least expensive systems costing less than $2,000. The systems are compared on several significant variables to aid in the process of selection. The uses of this type of color display system for research and instruction in psychology are described.
United States–India Collaborative Research Directions in Urban Housing and Supporting Infrastructure

By the year 2006, almost half of the world’s population is expected to live in urban settlements, and it is estimated that the global urbanization level will exceed 60% by the year 2030. Providing housing and supporting infrastructure such as water supply, sewerage, electricity, and accessibility to rapidly increasing urban populations worldwide is one of the key challenges for respective governments, industry, and international agencies. Urban housing and supporting infrastructure development is a major aspect of development policy for most developed as well as developing countries Global Trends 2004 . The United States and India represent most of the urban development characteristics associated with a typical developed and developing country, respectively. These two nations are actively working on developing strategies for dealing with urban housing and supporting infrastructure needs, and are facing tremendous challenges in these terms Kosambi 1994; Syal et al. 2002 . Presently, the U.S. construction industry spending is around $1 trillion and approximately 40% is spent on single and multi-family housing and about 25% is spent on the infrastructure Syal 2004 . In the case of India, current annual investment in construction is around $70 billion with an identified need for an additional $50 billion and a projected annual growth rate of 15%. It is estimated that supporting infrastructure will need an investment of around $163 billion over the next 10 years CIDC 2004 . Developing countries like India are experiencing a huge exodus of rural population into urban areas. These in-migrants are settling in the urban centers and peripheries. This trend is creating an urban crisis characterized by highly increased demand for
A Pathological Problem with NCEP Reanalyses in the Stratosphere.

A pathological problem has been discovered in the NCEP reanalyses in the stratosphere. It is manifested most strongly as a two-delta vertical wave in the divergence of the wind field above steep topography especially where the wind increases with altitude in the stratosphere. It is present primarily above 50 mb at the topmost four levels in the NCEP model used for data assimilation and appears to be directly related to the use of the sigma (terrain following) coordinate system and the upper boundary condition in the assimilating model. Recommendations suggested for addressing the problem include switching to a hybrid coordinate system that transitions to a pressure coordinate in the stratosphere, and with a damping upper boundary condition. Certain climate diagnostics are greatly impacted by these pathologies.