cssi/SciSciGPT-SciSciNet huggingface dataset:
Some examples of singular compact analytic surfaces which are homotopy equivalent to the complex projective plane

IN THEIR fundamental work[S] on analytic structures on the complex projective spaces Hirzebruch and Kodaira show in particular the following result in dimension two: If X is a compact complex Klhler manifold homeomorphic to the complex projective plane p = p(C) and with negative canonical line bundle, then X is analytically isomorphic to p. Indeed, it is easy to check that more is true (Proposition 4, Corollary 5 below): If X is a 2-(complex)-dimensional compact complex manifold with H,(X, Z) = 0 and second Betti number b*(X) = 1, then X is projective algebraic and II*(X, Z) is generated (over Z) by the Chern class of a positive (ample) line bundle L. If L admits a non-trivial section (which will be the case if the canonical bundle KX is negatiue) then X is biholomotphic to p. The purpose of this paper is to show by example that nevertheless there exist singular compact 2-dimensional complex spaces X which are homotopy equivalent with p, with H*(X, Z) = H*(p, Z) generated by the Chern class of the bundle of a positively embedded divisor P, and even with negative “canonical” bundle; and secondly, to give a uniqueness result in the form of an algorithm for constructing such spaces. In particular we show (Theorem 6 below): Let X be a 2-dimensional compact complex analytic space each of whose singular points is an isolated rational double point. Suppose that II*(X, Z) is isomorphic to Z[t]/(t3) and is generated by the Chem class of the line bundle of a holomorphic divisor T. Then X is biholomorphic either to p or to a singular rational projective algebraic surface obtained from p by the successive application of precisely 8 monoidal transformations followed by the collapsing of a curve with precisely 8 analytic components, each a non-singular rational curve with self-intersection 2, to 1 or more singular points. Every such space X is homotopy equivalent to p, and the generator T may always be taken to be the divisor of a non-singular elliptic curve contained in the regular points of X.
Current recommendations for initial therapy in hypertension: are they still valid? Introduction.

Abstract This symposium will address questions regarding current recommendations for initial therapy in the management of hypertension: Are we treating too many hypertensive patients or too few? When do we start treatment with medications and what medications should we use? Professor Lawrence Ramsay from England will discuss the concept of absolute versus relative risk and review the long-term hypertension treatment trials and what they have and have not told us. Dr. Michael Weber of New York will discuss some newer data on angiotensin converting enzyme inhibitors, angiotensin II receptor antagonists, and calcium channel blockers and attempt to answer the question: are these data sufficient to warrant recommending these agents as initial therapy? Finally, Dr. Henry Black of Chicago and I will update a new-old concept: is it time to consider low-dose fixed combination therapy as initial treatment in hypertension?
Immune Response to Sheep Red Blood Cells in Two Smyth Line Populations Homozygous for Different Major Histocompatibility Complex Haplotypes

The Smyth line (SL) chicken is characterized by a high incidence of spontaneous, posthatch, selective destruction of melanocytes, caused by an autoimmune phenomenon. It has been shown that the MHC is associated with the development and severity of the disease. To clarify further the role of MHC haplotypes and other factors leading to an autoimmune response, mean antibody titers to SRBC were determined for 37-wk-old females from 2 SL sublines (SL101 and SL102), each homozygous for a different MHC haplotype, their MHC-matched parental control sublines (BL101 and BL102), and a normally pigmented control, LBL. Although total incidence of amelanosis is approximately the same for both SL sublines, amelanosis occurs earlier and is more severe in SL101 birds. Within sublines, chickens were further classified as to the extent of the feather amelanosis. Neither SL MHC subline had a mean SRBC titer that differed significantly from unrelated LBL controls. Although the secondary response of the two sublines differed from each other (P < .05), neither differed from its MHC-matched parental control; therefore, the differences in immune response appear to be largely MHC-related and not closely related to melanocyte destruction. When SRBC titers were related to amelanotic severity, no differences were found within the SL101 subline, although, SL102 birds that became amelanotic at a later age had a lower primary response to SRBC (P < .05) than the more severely affected group. Birds simultaneously producing both pigmented and amelanotic feather tissue had higher (P < .05) primary and secondary anti-SRBC titers than did the complete amelanotics.
Representations of Reggeon Green's Functions-Their Scaling Form and the Approach to Scaling

We derive representations for Green's functions in the Reggeon calculus. Our renormalization-group integration method gives the $t$ dependence of the asymptotic scaling functions, as well as the correction terms which are present at nonasymptotic energies. The approach to the scaling form is governed by a critical exponent. The method can be used to calculate the scaling form and the approach to scaling of any $n\ensuremath{-}\mathrm{to}\ensuremath{-}m$ Reggeon Green's function. We discuss mainly the Pomeron propagator and the three-point function in the one-loop approximation.
Genetic and biochemical characterization of mutants at an RNA polymerase II locus in D. melanogaster

We previously described an alpha-amanitin-resistant mutant of D. melanogaster (AmaC4 or simply C4) with an altered, amanitin-resistant RNA polymerase II. We have now more fully characterized this mutant genetically and biochemically. We genetically mapped C4 to position 35.66 on the X chromosome and cytogenetically localized it to the polytene chromosome band interval 10C2-10D4. We then demonstrated that C4 is allelic to a previously known lethal-mutable locus I(1)L5 in this chromosomal region. Several known lethal alleles of L5 in fact affected the properties of RNA polymerase II in vitro. Following EMS mutagenesis of the C4-bearing chromosome we recovered new lethal L5 alleles, some of which were shown biochemically to have an altered amanitin-resistance polymerase II component. Furthermore, we induced mutants of C4 that had lost amanitin-resistance and showed that these mutants were also lethal alleles of L5. All the lethal alleles of L5 failed to completely complement each other genetically, and when analyzed biochemically their polymerase II displayed altered enzymatic properties. We conclude that C4 is an allele of the L5 locus and that this locus is most probably a structural gene for a subunit of RNA polymerase II. Some of the mutants at this locus display developmental abnormalities.
Overcoming the Bacteriostatic Activity of Onion in Making Standard Plate Counts

SUMMARY— The bacteriostatic activity of onion homogenates in making standard plate counts as reported in the literature was confirmed. It was found that potassium sulfite counteracts this activity. The sulfite must be added to the blending solution instead of to the petri plate. Five-tenths percent sulfite is sufficient and the concentration may be as high as 1.6%. Variety of onion did not appear to be a factor. This treatment was of value with both laboratory and commercially dehydrated onions. Coliform organisms were not inhibited by sulfite. It is recommended that all standard plate counts of onion be made with 0.5% K2SO8, in the blending solution.
Psychotherapy with dual diagnosis patients: Working with denial

The author discusses a strategy of working with chronically impaired dual diagnosis patients who are in denial of their substance abuse problems. It is argued that due to a number of unique features among such patients, directly confronting denial and insisting on abstinence will not be effective for many of these patients. Instead, it is suggested that patients' continued substance use should be tolerated although at the same time be made a focus of treatment. Techniques are offered which can be utilized to broach the denial of this challenging patient population. Types of patients not suitable for this approach are also discussed.
Predicting circuit aging using ring oscillators

This paper presents a method for inferring circuit delay shifts due to bias temperature instability using ring oscillator (ROSC) sensors. This procedure is based on presilicon analysis, postsilicon ROSC measurements, a new aging analysis model called the Upperbound on fMax (UofM), and a look-up table that stores a precomputed degradation ratio that translates delay shifts in the ROSC to those in the circuits. This method not only yields delay estimates within 0.2% of the true values with very low runtime, but is also independent of temperature and supply voltage variations.
Two-Color Imaging Radiometry For Pyrotechnic Diagnostics

Two-color radiometry is a well-known technique for temperature measurement and is routinely used in such applications as astronomy and photography. We have applied the technique in some new ways for determination of the ensemble graybody temperature and the matter distribution in plumes of solid products of pyrotechnic reactions in vacuum. Each resolution element of interest is measured simultaneously in time and space at two different wavelengths and the desired results derived. A commercially available two-color imaging radiometer provides sufficient resolution in the temporal, spectral, and spatial domains for our application. We measure to useful accuracy temperature in the 400°C to 1200°C range and ensemble emissivities ranging from 10-1 to 10-4 in plumes produced pyrotechnically. Optical bandpass changes in the sensor, special calibrations, and special computer codes to achieve these results are described.
Supporting random access on real-time retrieval of digital continuous media

In addition to the large data size requirement and real-time constraint in continuous media, future video applications such as video editing demand a random access capability at the video-frame level. This paper introduces our study on effective buffering control for the real-time retrieval of jitter-free digital video medium. We adopt a video-frame level approach to maintaining the flexibility on placement and analysing the efficiency of the buffering schemes. An integrated solution which offers efficient buffering schemes and flexible storage placement to support random access is our goal. We present two buffering schemes: the two-buffer scheme and the k-buffer compensation scheme. The two-buffer scheme requires that all the frames in a block are stored consecutively, while providing random access between blocks. However, this intuitive buffering scheme potentially requires a large block size and buffer space. The k-buffer compensation scheme is proposed to resolve this large buffer space requirement, by using more than two buffers and requiring a minimal number of blocks randomly placed in each cylinder. This scheme differs from the contiguous placement scheme because individual blocks can be stored anywhere in each cylinder. Compared to the two-buffer scheme, the k-buffer compensation scheme requires less buffer space, has higher disk utilization and finer granularity on disk data transfer. The placement requirements are more flexible and implementable than the contiguous and storage pattern placement schemes. Experimental measurement results reveal the significant improvements on the buffer-size reduction and placement flexibility by using the k-buffer compensation scheme. Extensions of the k-buffer compensation scheme to support multiple streams are also addressed.
Retinoids directly activate the collagen X promoter in prehypertrophic chondrocytes through a distal retinoic acid response element

Retinoids are essential for the terminal differentiation of chondrocytes during endochondral bone formation. This maturation process is characterized by increased cell size, expression of a unique extracellular matrix protein, collagen X, and eventually by mineralization of the matrix. Retinoids stimulate chondrocyte maturation in cultured cells and experimental animals, as well as in clinical studies of synthetic retinoids; furthermore, retinoid antagonists prevent chondrocyte maturation in vivo. However, the mechanisms by which retinoids regulate this process are poorly understood. We and others showed previously that retinoic acid (RA) stimulates expression of genes encoding bone morphogenetic proteins (BMPs), suggesting that retinoid effects on chondrocyte maturation may be indirect. However, we now show that RA also directly stimulates transcription of the collagen X gene promoter. We have identified three RA response element (RARE) half-sites in the promoter, located 2,600 nucleotides upstream from the transcription start site. These three half-sites function as two overlapping RAREs that share the middle half-site. Ablation of the middle half-site destroys both elements, abolishing RA receptor (RAR) binding and drastically decreasing RA stimulation of transcription. Ablation of each of the other two half-sites destroys only one RARE, resulting in an intermediate level of RAR binding and transcriptional stimulation. These results, together with our previously published data, indicate that retinoids stimulate collagen X transcription both directly, through activation of RARs, and indirectly, through increased BMP production.
New techniques in the measurement of multifactor productivity

This article outlines procedures for adjustment for characteristics of the production structure which are typically ignored in productivity growth computations but affect the correct valuation of inputs and outputs. There are many such characteristics, including changes in the terms of trade and fixity of factors, but only one appears to have much impact on productivity fluctuations: imperfect competition in output and input markets. To illustrate this, traditional and adjusted productivity growth indexes based on assumed markups are constructed for the U.S., Canadian and Japanese business sectors for comparison with each other and with other adjustments done in previous studies. The methodology is based on finding shadow values of all domestic and traded outputs and inputs to use to evaluate the contribution of each to profits. We find that evidence of markups suggests adjustments in traditional measures that are quite significant and which tend to smooth both cyclical and time trends in productivity growth.
Building Trust Between Consumers and Corporations: The Role of Consumer Perceptions of Transparency and Social Responsibility

Developing trust in a company is a significant part of building the company-consumer relationship. Previous studies have sought to identify the positive consequences of trust such as loyalty and repurchase, but the question of what builds trust remains largely unanswered. To answer the question, we developed a model that depicts the relationships among transparency, social responsibility, trust, attitude, word-of-mouth (WOM) intention, and purchase intention. An online survey was conducted with a US nationwide sample of 303 consumers, and the data were analyzed using the structural equation modeling method. The results indicated that consumers’ perceptions of a corporation’s efforts to be transparent in the production and labor conditions and to be socially responsible by giving back to the local community directly affected these consumers’ trust and attitudes toward the corporation, and indirectly affected their intentions to purchase from and spread positive WOM about the corporation. Theoretical and practical implications are discussed.
Analysis of Free Vibration of STRUCTURAL ACOUSTIC Coupled Systems, Part i: Development and Verification of the Procedure

Abstract A new procedure to formulate and analyze the free vibration problem of structural-acoustic coupled systems is suggested. The system equations are formulated utilizing the concept of the equivalent mass source. The modal expansion method and a matrix transformation technique are used to solve the system equations to obtain the natural frequencies and modes of system. The procedure is verified by comparing its result with the exact solution of a one-dimensional coupled system. Parameters dictating coupling effects are also identified and discussed.
Nd-YAG laser as a palliative treatment for malignant dysphagia.

Two hundred and twenty-four patients with histologically-confirmed carcinoma of the oesophagus received palliative Nd-YAG laser therapy for malignant dysphagia between January 1986 and December 1994. The results are appraised in terms of the degree of relief obtained, its relation to the macroscopic type and the size of the tumour, peri-operative complications, duration of hospitalization and survival after treatment. Recannulation of the oesophageal lumen was obtained in 98.2% of the patients, after which 93.7% were able to ingest at least semi-solids. Although the lumen was permeable for a 9.8 mm endoscope, the remainder could only ingest liquids. The only complication was a perforation in six cases (2.7%). After treatment, 14.8% survived more than I year and 3.4% more than 2 years. After discussing the role of lasers in the palliative treatment of malignant dysphagia, the authors conclude that it can be considered effective in that it relieves the dysphagia and improves the patients' quality of life.
Adventures with ARIMA software

Abstract Many software packages are available for fitting autoregressive inegrated moving average models to time-series data. The practitioner is faced with a wide choice of programs for fitting these models. As we illustrate in this paper, the results obtained can depend substantially in important respects on the particular choice that is made. Our examples serve as a basis for exploring the causes of this phenomenon.
Probing the interplay between electrostatic and dispersion interactions in the solvation of nonpolar nonaromatic solute molecules in ionic liquids: An OKE spectroscopic study of CS2/[CnC1im][NTf2] mixtures (n = 1–4)

The intermolecular dynamics of dilute solutions of CS2 in 1-alkyl-3-methylimidazolium bis[(trifluoromethane)sulfonyl]amide ([CnC1im][NTf2] for n = 1–4) were studied at 295 K using femtosecond optical Kerr effect (OKE) spectroscopy. The OKE spectra of the CS2/ionic liquid (IL) mixtures were analyzed using an additivity model to obtain the CS2 contribution to the OKE spectrum from which information about the intermolecular modes of CS2 in these mixtures was gleaned. The intermolecular spectrum of CS2 in these mixtures is lower in frequency and narrower than that of neat CS2, as found previously for CS2 in [C5C1im][NTf2]. Moreover, a dependence of the spectra on alkyl chain length is observed that is attributed to the interplay between electrostatic and dispersion interactions. The surprising result in this study is the solubility of CS2 in [C1C1im][NTf2], which involves the interaction of a nonpolar nonaromatic molecular solute and only the charged groups of the IL. We propose that the solubility of CS2 in [C1C1im][NTf2] is determined by three favorable factors – (1) large polarizability of the solute molecule; (2) small size of the solute molecule; and (3) low cohesive energy in the high-charge density regions of the IL.
Performance limitations of the self-filtering unstable resonator

Abstract The self-filtering unstable resonator (SFUR) can provide excellent mode properties for high-gain lasers having active-medium Fresnel numbers up to a few times unity or perhaps a few tens. This note is merely to point out that the SFUR design is generally not suitable for much larger Fresnel number devices, because the output coupling that results for single-mode operation with full energy extraction then becomes unacceptably large.
Occurrence and Distribution of Triticum mosaic virus in the Central Great Plains

Abstract Wheat curl mite (WCM)-transmitted viruses—namely, Wheat streak mosaic virus (WSMV), Triticum mosaic virus (TriMV), and the High Plains virus (HPV)—are three of the wheat-infecting viruses in the central Great Plains of the United States. TriMV is newly discovered and its prevalence and incidence are largely unknown. Field surveys were carried out in Colorado, Kansas, Nebraska, and South Dakota in spring and fall 2010 and 2011 to determine TriMV prevalence and incidence and the frequency of TriMV co-infection with WSMV or HPV in winter wheat. WSMV was the most prevalent and was detected in 83% of 185 season–counties (= s-counties), 73% of 420 season–fields (= s-fields), and 35% of 12,973 samples. TriMV was detected in 32, 6, and 6% of s-counties, s-fields, and samples, respectively. HPV was detected in 34, 15, and 4% of s-counties, s-fields, and samples, respectively. TriMV was detected in all four states. In all, 91% of TriMV-positive samples were co-infected with WSMV, whereas WSMV and HPV were ...
Determination of primary and secondary solvation numbers and binding constants based on the shift of a proton-transfer equilibrium resulting from hydrogen bonding solvation

We show how the shift in the equilibrium constant K PT for formation of a proton-transfer adduct in a non-interactive solvent, upon addition of a second, hydrogen-bonding solvent S reveals the nature of the hydrogen bonding solvation process. Data are analyzed for the pentachlorophenoltriethylamine proton-transfer equilibrium in cyclohexane solvent, under-going solvation by the acidic alcohols, 2,2,2-trichloroethanol and 1,1,1,3,3,3-hexafluoro-2-propanol. K PT vs. [S] data are fitted to a binding isotherm corresponding to two-stage solvation of both the adduct and the free amine. Stoichiometries and binding constants for both primary and secondary solvation of both solvated species are determined as adjustable parameters. Best fits correspond to both the adduct and free amine under-going primary solvation by one alcohol molecule (presumably at the oxygen and nitrogen lone-pairs, respectively) followed by secondary solvation by one to nine additional alcohol molecules, with binding constants ranging from 2100 M−1, for primary solvation of the adduct by hexafluoro-2-propanol, down to 7 M−1, for secondary solvation of the amine by trichloroethanol. We speculate that the secondary solvation numbers represent average sizes of hydrogen-bonded alcohol chains, nucleated by the enhanced basicity of the primary-solvation alcohol.
TEST REVIEW: Dean C. Delis, Edith Kaplan & Joel H. Kramer, Delis Kaplan Executive Function System (D-KEFS), The Psychological Corporation, San Antonio, TX, 2001. $415.00 (complete kit)

(2006). TEST REVIEW: Dean C. Delis, Edith Kaplan & Joel H. Kramer, Delis Kaplan Executive Function System (D-KEFS), The Psychological Corporation, San Antonio, TX, 2001. $415.00 (complete kit) Applied Neuropsychology: Vol. 13, No. 4, pp. 275-27.
Modules semicocritical with respect to a torsion theory and their applications

The concepts of primitive ideal and semicocritical module with respect to a torsion theory are studied and related to the structure of torsionfree injective modules. Applications are made to the study of (1) composition series with respect to a torsion theory and (2) the structure of endomorphism rings of torsionfree modules. These results are natural generalizations of the properties of certain modules over (noetherian) rings with Krull dimension.
How much surface water can gilgai microtopography capture

Summary Gilgai microtopography is associated with landscapes of strongly shrinking–swelling soils (Vertisols) and affects spatial and temporal variability of runoff, and thus the generation of stream flow and plant-available water. However, no report is available on the amount of surface water that a landscape with gilgai depressions can retain. Our objective was to assess water capturing capacity of a typical Vertisol landscape with gilgai depressions in the Blackland Prairie Major Land Resource Area of Texas. The 45 by 40 m study site was located on a Vertisol with circular gilgai covered by improved pasture on a summit with slope of less than 3%. A digital elevation model (DEM) with 0.25 m2 cell size was created from elevation data acquired by using GPS. Water capturing capacity of gilgai depressions was estimated at 10 randomly selected local gilgai basins by analyzing spatial distribution of Topographic Wetness Index (TWI). Our findings indicate that the average circular gilgai depression can hold 0.78 m3 of water leading to an estimate of 0.024 m3 m−2 water capturing capacity in a circular gilgai landscape, assuming no infiltration. The gilgai could capture a maximum of 43.74 m3 of rain and runoff water at the 1800 m2 study site. Consequently, if the soil were saturated and not infiltrating any water, no runoff would be expected following a 24.3 mm m−2, 1 h precipitation, affecting estimates of streamflow (runoff) and plant available water (redistribution and infiltration) at the m to km scale.
X-ray FEL: an experimenter's dilemma

The specifications of presently proposed x-ray free electron lasers (FELs) are for machines that will provide x-ray pulses as short as 100 fs with a photon energy as high as 12.3keV. Since the pulse will contain as much as 13 mJ of energy, these devices will present the experimenter with an opportunity to expose matter to an unprecedented x-ray energy density. This high concentration of energetic x-rays presents both a promising frontier in energy-matter interaction, as well as a technological crevasse to be crossed by the experimenter attempting to use the FEL beam. We shall look at three possible problems confronting the experimenter: (1) synchronization of a detector, laser pulse, etc., to the FEL pulse; (2) radiation damage to the target sample; and (3) the presence of an electromagnetic pulse that could damage sensitive electronics located in the experimental area.
Magnetic anisotropy of single crystal HoFe3

The magnetization of single crystal HoFe3 has been measured as a function of applied field direction and temperature for H⩽100 kOe and 20K⩽T⩽300K. The compound exhibits essentially easy‐basal plane anisotropy with anisotropy fields in excess of 150 kOe. The easy magnetization direction remains b‐axis throughout the temperature range but a significant spontaneous magnetization persists along the hard c‐axis. Two alternative models for the magnetic structure are proposed which fit the observed field direction dependence of the net moment. Both require the Ho moments to depart the basal plane for field directions other than b.
A microtechnique for determining the surface tension of a liquid

When a small liquid bridge is placed between a sphere and a flat surface, an attractive force is generated that opposes the separation of the two solid surfaces. Our detailed theoretical analysis of the phenomenon leads to a general relationship that predicts how this force depends on the surface tension and other factors. Earlier investigators have offered a simplified relationship, force = 4πRγ (where R is the sphere radius), as a possible basis for measuring the surface tension γ, which has the advantage of being independent of the amount of liquid in the bridge. This simplification will always underestimate γ, but the potential error becomes almost trivial if the amount of liquid is reduced below a critical level that will usually be in the submicroliter range. A simple procedure for obtaining reliable data with very small liquid volumes is described, and some typical results are presented.
Electronic Density of States of Atomically Resolved Single-Walled Carbon Nanotubes: Van Hove Singularities and End States

The electronic densities of states of atomically resolved single-walled carbon nanotubes have been investigated using scanning tunneling microscopy. Peaks in the density of states due to the one-dimensional nanotube band structure have been characterized and compared with tight-binding calculations. In addition, tunneling spectroscopy measurements recorded along the axis of an atomically resolved nanotube were found to exhibit new, low-energy peaks in the density of states near the tube end. Calculations suggest that these features arise from the specific arrangement of carbon atoms that close the nanotube end.
N-STRING TANGLES

An n-string tangle (B, T) is a 3-ball B containing n properly embedded arcs T={ti}. An n-string tangle (B, T) is called rational if it is a homeo-morphism of pairs from (B, T) to (D, P)×I where D is the unit disk, P is any set of n points in the interior of D and I is the unit interval on the real line. In this article we begin to generalize the well known classification of 2-string rational tangles to rational tangles with three or more strings. A symbol describing an n-string rational tangle and an algebraic topological invariant is developed.
Biodegradable Multiblock Poly[N-(2-hydroxypropyl)methacrylamide] via Reversible Addition−Fragmentation Chain Transfer Polymerization and Click Chemistry

A new bifunctional chain transfer agent (CTA) containing alkyne end groups was designed, synthesized, and used for direct synthesis of clickable telechelic polymers. Good control of reversible addition−fragmentation chain transfer (RAFT) polymerization of N-(2-hydroxypropyl)methacrylamide (HPMA) was achieved by using the new CTA, as indicated by a linear increase of number-average molecular weight (Mn) with conversion and low polydispersity (PDI) (<1.1). In particular, enzymatically degradable multiblock HPMA polymers were readily prepared by subsequent reaction with α,ω-diazido-oligopeptide (GFLG) sequence via CuI-catalyzed alkyne−azide cycloaddition. Upon exposure of high molecular weight fractions of multiblock polyHPMA to papain or cathepsin B, the polymer was degraded into segments of molecular weight and narrow polydispersity similar to those of the initial telechelic polyHPMA.
Gene Ontology analysis in multiple gene clusters under multiple hypothesis testing framework

Objective: Gene Ontology (GO) has become a routine resource for functional analysis of gene lists. Although a number of tools have been provided to identify enriched GO terms in one or two gene lists, two technical challenges remain. First, how to handle multiple hypothesis testing in the analysis given that the tests are heavily correlated; second, how to identify GO terms that are enriched in a gene cluster, as compared to multiple other gene clusters. We provide a statistical procedure to rigorously treat these problems and offer a software tool for applying GO to the analysis of gene clusters. Methods: We previously introduced a statistical procedure that handles hypothesis testing in a two-group comparison scenario. In this paper we extend the two-group comparison procedure into a general procedure that enables the analysis of any number of gene lists/clusters. This new procedure enables identification of GO terms enriched in any gene cluster, while it controls for multiple hypothesis testing. This procedure is implemented into a user-friendly analysis tool: GoSurfer. The current version of GoSurfer takes one or several gene lists as input, and it identifies the GO terms that are enriched in any of the input gene lists. GoSurfer estimates a conservative false discovery rate (FDR) for every GO term. The FDR estimation procedure in GoSurfer has two advantages: it does not rely on independence assumption, and it does not assume all the hypotheses are null hypothesis (complete null). Thus GoSurfer's FDR estimates are mildly conservative rather than overly conservative. Results: We implemented the new procedure for GO analysis in multiple gene clusters into the GoSurfer software. We provide three examples on using GoSurfer to analyze time course gene expression data sets on the differentiation of embryonic stem cells. In the example of analysis of multiple gene clusters, we first used a typical clustering algorithm and identified five gene clusters, representing up-regulation, down-regulation and other patterns in the differentiation time course. Taking all the five gene clusters as input data, GoSurfer reports ''cell adhesion'' and ''muscle contraction'' as significant GO terms for the up-regulated cluster, ''amino acids metabolism'' as a significant GO term for the down-regulated gene cluster, and GoSurfer reports a number of GO terms related to RNA processing and RNA transport as significant terms to a cluster that is up-regulated in both early and late time points. This may suggest that genes for RNA processing and genes for RNA transport are coregulated in the differentiation process of embryonic stem cells. Conclusion: The GoSurfer software is provided to analyze multiple gene clusters and identify GO terms that are enriched in any gene cluster. Gosurfer is available at: www.gosurfer.org.
Santa Cruz mountains (Loma Prieta) earthquake

At 5:04 P.M. on Tuesday, October 17, 1989 local time (10/18/89 00:04:15.23 UT) a large earthquake ruptured a 40-km segment of the San Andreas fault in the Santa Cruz Mountains in northern California. The magnitude Ms was calculated at 7.1 by the National Earthquake Information Service using data from 18 stations. This report is based on information made available to geophysicists at the C. F. Richter Seismological Laboratory at the University of California at Santa Cruz (UCSC), as of 10 days following the main shock. The Santa Cruz Mountains (Loma Prieta) earthquake was the most severe in the continental U.S. since 1952, when a very large earthquake (Ms = 7.7) broke along the White Wolf fault near Bakersfield, Calif. It was the largest event on the San Andreas since the 1906 (M = 8.3) San Francisco event.
Mechanistic Investigation of Iridium-Catalyzed Hydrovinylation of Olefins

C_2H_3-Ir(III)(acac-O,O)2(Py) dimerizes olefins through a C−H activation mechanism. The starting catalyst first isomerizes to the cis conformer through a dissociative process, where pyridine is lost, and then adds the olefin substrate to the cis conformer. [1,2]-Insertion of the vinyl moiety into the coordinating olefin generates a Ir−CH_2−CH_2−CH ═ CH_2 complex, which then isomerizes to an Ir(η^3-allyl) complex through a series of β-hydride transfer reactions. The η^3-allyl complex is significantly more stable than any other part of the surface and is expected to be the resting state of the catalyst. Addition of a second olefin to the η^3-allyl complex leads to an Ir−(CH_2−CH ═ CH−CH_3) complex with a coordinating olefin, which can transfer a hydrogen to the product, 2-butene, via a C−H activation transition state. This transition step is the rate-determining step, with a calculated ΔH^⧧ = 31.6 kcal/mol and ΔG^⧧ = 32.1 kcal/mol. Other pathways were found to have reasonable barriers, but are not competitive due to very facile barriers leading to the η^3-allyl complex. From the allyl complex, neither 1-butene or butadiene are feasible products. The presence of 1-butene in the product mixture is attributed to isomerization of 2-butene; that is, it is not a kinetic product.
Chemical and isotopic composition of high-molecular-weight dissolved organic matter from the Mississippi River plume

article In order to examine the source and transformation of high-molecular-weight dissolved organic matter (HMW-DOM) in the mixing zone of the Mississippi River plume, HMW-DOM with sizes between 1 kDa and 0.2 μm was collected along a salinity gradient using cross-flow ultrafiltration. Isolated OM samples were desalted, freeze-dried and characterized for elemental (C and N) and biochemical composition (proteins, carbohydrates and uronic acids), stable isotopic (δ 13 C and δ 15 N) and radiocarbon (Δ 14 C) signatures, and relative molecular composition using pyrolysis-gas chromatography/mass spectrometry. The organic carbon content of HMW-DOM samples ranged from 31 to 36 wt.%, indicating that isolated colloids are mostly organic in nature. Contents of N ranged from 1.9% to 3.3%, resulting in a C/N ratio of 19-20 at lower salinity stations with a strong influence by terrestrial DOM and 12-15 at higher salinity stations with more freshly photosynthesized marine DOM. While OC-normalized protein contents decreased with increasing salinity, both carbohydrate and uronic acid contents increased with increasing salinity. Variations of pyrograms demonstrated that the proportion of furfural (an indicator of polysaccharides) in HMW-DOM also increased with increasing salinity, while the proportion of phenols decreased with increasing salinity. Changes in carbohydrate, (acid) polysaccharide and phenol contents of HMW-DOM samples reflect the variation in DOM sources along the salinity gradient, with higher phenol and low polysaccharide contents in lower salinity areas but higher polysaccharide and low phenol contents in coastal waters. Values of δ 13 C increased from
Developmental influences on medically unexplained symptoms.

Background: Medically unexplained (or ‘functional’) symptoms (MUS) are physical symptoms that prompt the sufferer to seek healthcare but remain unexplained after an appropriate medical evaluation. Examples of MUS also occur in veterinary medicine. For example, domestic cats suffer a syndrome comparable to interstitial cystitis, a chronic pelvic pain syndrome of humans. Method: Review of current evidence suggests the hypothesis that developmental factors may play a role in some cases of MUS. Maternal perception of a threatening environment may be transmitted to the fetus when hormones cross the placenta and affect fetal physiology, effectively ‘programming’ the fetal stress response system and associated behaviors toward enhanced vigilance. After birth, intense stress responses in the individual may result in similar vulnerability, which may be unmasked by subsequent stressors. Results: Epigenetic modulation of gene expression (EMGEX) appears to play a central role in creation of this ‘survival phenotype’. The recent development of techniques to identify the presence of EMGEX provides new tools to investigate these questions, and drugs and other interventions that may reverse EMGEX are also under active investigation. Conclusion: Viewing MUS from the perspective of underlying developmental influences involving EMGEX that affect function of a variety of organs based on familial (genetic and environmental) predispositions rather than from the traditional viewpoint of isolated organ-originating diseases has at least two important implications: it provides a parsimonious explanation for findings heretofore difficult to reconcile, and it opens whole new areas of investigation into causes and treatments for this class of disorders.
Exact Forwarding Table Partitioning for Efficient TCAM Power Savings

Excessive power consumption is deemed one of the major drawbacks of TCAM-based IP search engines. This paper proposes a simple and yet efficient forwarding table partitioning algorithm aiming to achieve significant TCAM power savings. Our algorithm partitions the IP address space into a set of adjoining but non-overlapping search ranges comprising an exactly identical number of prefixes to be accommodated in a TCAM segment, dubbed exact table partitioning (ETAP). During a search operation, only one single range is examined to reduce overall TCAM power consumption substantially.
Optimal discrete bit loading for multicarrier modulation systems

In this work the problem of discrete bit allocation for multicarrier modulation systems is considered. Necessary and sufficient conditions for optimality are introduced along with algorithms for solving the discrete bit allocation problems for a general class of channels. These results can be used to construct efficient loading algorithms in practice.
Design and Precision Control of an MR-Compatible Flexible Fluidic Actuator

Magnetic resonance imaging (MRI) offers many benefits to image-guided interventions, including excellent soft tissue distinction, little to no repositioning of the patient, and zero radiation exposure. The closed, narrow bore of a high field MRI scanner limits clinician access to the patient, such that an MR-compatible robot is essentially required for many potential interventions. A robotic system of this kind could additionally provide the clinician increased accuracy and more degrees of freedom within the minimally invasive context. Fluid power is an excellent type of actuation to use inside the MRI scanner, as such actuators can be designed free of magnetic and electrical components. However, there are no fluid power actuators readily available that are suitable for use in the operating room. This paper reports a compact, intrinsically safe, sterilizable fluid power actuator. Using additive manufacturing processes, the actuator was printed in a single build. Thus, it is composed of several integrated parts in a compact design. Employing an inchworm-like behavior, the linear actuator can advance or retract a needle or mechanism rod in discrete steps; thus the device is intrinsically safe. The actuator is fluid agnostic, but a pneumatic prototype is presented here with initial testing results. For the pneumatic case, sub-step positioning control has been tested using a nonlinear, modelbased controller, and the mean steady-state error was 0.025 mm. Thus this type of actuator appears to be promising solution for use in MRI-guided interventions.
Plant community feedbacks and long-term ecosystem responses to multi-factored global change

While short-term plant responses to global change are driven by physiological mechanisms, which are represented relatively well by models, long-term ecosystem responses to global change may be determined by shifts in plant community structure resulting from other ecological phenomena such as interspecific interactions, which are represented poorly by models. In single-factor scenarios, plant communities often adjust to increase ecosystem response to that factor. For instance, some early global change experiments showed that elevated CO2 favours plants that respond strongly to elevated CO2, generally amplifying the response of ecosystem productivity to elevated CO2, a positive community feedback. However, most ecosystems are subject to multiple drivers of change, which can complicate the community feedback effect in ways that are more difficult to generalize. Recent studies have shown that (i) shifts in plant community structure cannot be reliably predicted from short-term plant physiological response to global change and (ii) that the ecosystem response to multi-factored change is commonly less than the sum of its parts. Here, we survey results from long-term field manipulations to examine the role community shifts may play in explaining these common findings. We use a simple model to examine the potential importance of community shifts in governing ecosystem response. Empirical evidence and the model demonstrate that with multi-factored change, the ecosystem response depends on community feedbacks, and that the magnitude of ecosystem response will depend on the relationship between plant response to one factor and plant response to another factor. Tradeoffs in the ability of plants to respond positively to, or to tolerate, different global change drivers may underlie generalizable patterns of covariance in responses to different drivers of change across plant taxa. Mechanistic understanding of these patterns will help predict the community feedbacks that determine long-term ecosystem responses.
A Large Terrestrial Carbon Sink in North America Implied by Atmospheric and Oceanic Carbon Dioxide Data and Models

Atmospheric carbon dioxide increased at a rate of 2.8 petagrams of carbon per year (Pg C year 21 ) during 1988 to 1992 (1 Pg 5 10 15 grams). Given estimates of fossil carbon dioxide emissions, and net oceanic uptake, this implies a global terrestrial uptake of 1.0 to 2.2 Pg C year 21 . The spatial distribution of the terrestrial carbon dioxide uptake is estimated by means of the observed spatial patterns of the greatly increased atmospheric carbon dioxide data set available from 1988 onward, together with two atmospheric transport models, two estimates of the sea-air flux, and an estimate of the spatial distribution of fossil carbon dioxide emissions. North America is the best constrained continent, with a mean uptake of 1.7 6 0.5 Pg C year 21 , mostly south of 51 degrees north. Eurasia—North Africa is relatively weakly constrained, with a mean uptake of 0.1 6 0.6 Pg C year 21 . The rest of the world’s land surface is poorly constrained, with a mean source of 0.2 6 0.9 Pg C year 21 .
Parental care in the long-tailed skink, Mabuya longicaudata on a tropical Asian island

Parental care has been reported in more than 140 species of reptiles (about 3%), but few records unambiguously demonstrate the selective value of that care. I experimentally investigated the influence of maternal attendance on survival of eggs in the long-tailed skink, Mabuya longicaudata, on Orchid Island, Taiwan, by placing sympatric reptiles, both predators and nonpredators, into nests. Without maternal care, most lizard eggs were eaten by the egg-eating snake, Oligodon formosanus. Female lizards with eggs attacked snakes more often and escaped from snakes less often than did females without eggs. Survival of eggs was lower when females were removed from clutches than when they were left in attendance. All egg loss in unprotected nests on Orchid Island was due to predation by O. formosanus. Size of snakes did not determine whether lizards abandoned egg-free nests or nests with eggs when attacked. Females that attacked egg predators had larger clutches than those that did not attack. Females recognized sympatric lizards and did not attack species that do not prey on eggs or on M. longicaudata, but recognized the predatory snake Elaphe carinata and escaped when that species entered the nest. These findings emphasize the ecological importance of an increased understanding of the function of parental care in reptiles.
Lingual muscle activity across sleep-wake States in rats with surgically altered upper airway.

Obstructive sleep apnea (OSA) patients have increased upper airway muscle activity, including such lingual muscles as the genioglossus (GG), geniohyoid (GH) and hyoglossus (HG). This adaptation partially protects their upper airway against obstructions. Rodents are used to study the central neural control of sleep and breathing but they do not naturally exhibit OSA. We investigated whether, in chronically instrumented, behaving rats, disconnecting the GH and HG muscles from the hyoid (H) apparatus would result in a compensatory increase of other upper airway muscle activity (EMG) and/or other signs of upper airway instability. We first determined that, in intact rats, lingual (GG and intrinsic) muscles maintained stable activity levels when quantified based on 2 h-long recordings conducted on days 6 through 22 after instrumentation. We then studied 5 rats in which the tendons connecting the GH and HG muscles to the H apparatus were experimentally severed. When quantified across all recording days, lingual EMG during SWS was modestly but significantly increased in rats with surgically altered upper airway (8.6% ±0.7(SE) vs. 6.2% ±0.7 of the mean during wakefulness; p=0.012). Respiratory modulation of lingual EMG occurred mainly during SWS and was similarly infrequent in both groups, and the incidence of sighs and central apneas also was similar. Thus, a weakened action of selected lingual muscles did not produce sleep-disordered breathing but resulted in a relatively elevated activity in other lingual muscles during SWS. These results encourage more extensive surgical manipulations with the aim to obtain a rodent model with collapsible upper airway.