cssi/SciSciGPT-SciSciNet huggingface dataset:
Antioxidant actions of beta-carotene in liposomal and microsomal membranes: role of carotenoid-membrane incorporation and alpha-tocopherol.

Abstract β-Carotene and other carotenoids are widely regarded as biological antioxidants. However, recent clinical trials indicate that β-carotene supplements are not effective in disease prevention and raise questions about the biological significance of carotenoid antioxidant actions. To further explore this issue, we have reevaluated the antioxidant actions of β-carotene in liposomal and biological membrane systems. In dilinoleoylphosphatidylcholine liposomes in which 0.35 mol % β-carotene was incorporated into the bilayer during liposome preparation, the carotenoid inhibited lipid peroxidation initiated by 10 m m azobis[amidinopropane HCl] (AAPH). In carotenoid-free liposome suspensions to which the same amount of β-carotene was added, no antioxidant effect was observed. Supplementation of rat liver microsomes with β-carotenein vitroyielded microsomes containing 1.7 nmol β-carotene mg−1and 0.16 nmol α-tocopherol mg−1microsomal protein. In β-carotene supplemented microsomes incubated with 10 m m AAPH under an air atmosphere, lipid peroxidation did not occur until α-tocopherol was depleted by approximately 60%. β-Carotene exerted no apparent antioxidant effect and was not significantly depleted in the incubations. Similar results were obtained when the incubation was done at 3.8 torr O2. In liver microsomes from Mongolian gerbils fed β-carotene-supplemented diets, β-carotene levels were 16–37% of α-tocopherol levels. The kinetics of AAPH-induced lipid peroxidation were no different in β-carotene-supplemented microsomes than in microsomes from unsupplemented animals, although the kinetics of β-carotene and α-tocopherol depletion were similar. The results indicate that β-carotene is ineffective as an antioxidant when added to preformed lipid bilayer membranes and that α-tocopherol is a much more effective membrane antioxidant than β-carotene, regardless of the method of carotenoid-membrane incorporation. These results support a reevaluation of the proposed antioxidant role for β-carotene in biological membranes.
Poly-(R)-3-Hydroxybutyrate-Modified Proteins

Poly-(R)-3-hydroxybutyrate (PHB), a linear polymer of R-3-hydroxybutyrate (R-3HB), is a universal constituent of biological cells. Short-polymers of PHB (<15 residues) are covalently attached to certain prokaryotic and eukaryotic proteins (PHBylation) - primarily proteins of membranes and organelles. PHB is an amphiphilic, water-insoluble, lipid-soluble molecule that may form hydrophobic, hydrogen and coordinate bonds. The PHB backbone is highly flexible at physiological temperatures but becomes increasingly more rigid as temperatures are lowered. These physical properties indicate that PHBylation plays important roles in the targeting, folding, structure and function of PHB-modified proteins, and also promotes interactions between proteins and polyanions such as RNA, DNA and inorganic polyphosphate (polyP).
Reproducing Kernel Hilbert Spaces for Penalized Regression: A Tutorial

Penalized regression procedures have become very popular ways to estimate complicated functions. The smoothing spline, for example, is the solution of a minimization problem in a functional space. If such a minimization problem is posed on a reproducing kernel Hilbert space (RKHS), the solution is guaranteed to exist, is unique, and has a very simple form. There are excellent books and articles about RKHS and their applications in statistics; however, this existing literature is very dense. This article provides a friendly reference for a reader approaching this subject for the first time. It begins with a simple problem, a system of linear equations, and then gives an intuitive motivation for reproducing kernels. Armed with the intuition gained from our first examples, we take the reader from vector spaces to Banach spaces and to RKHS. Finally, we present some statistical estimation problems that can be solved using the mathematical machinery discussed. After reading this tutorial, the reader will be rea...
Epidural Anesthesia for Obstetric Patients

The use of epidural anesthesia for the obstetric patient is increasing in many areas of the country. The maternity nurse needs to have a basic understanding of the technique used by the physician to initiate this type of anesthesia, and also has a responsibility to know the contraindications, possible complications, and disadvantages and advantages of epidural anesthesia. This information is presented below. Skilled nursing and medical management will reduce the potential risks of epidural anesthesia for both the mother and fetus.
3kV 4H-SiC Thyristors for Pulsed Power Applications

Due to the Silicon Carbide (SiC) material’s high electric field strength, wide bandgap, and good thermal conductivity, 4H-SiC thyristors are attractive candidates for pulsed power applications. With a thinner blocking layer almost an order of magnitude smaller than its Silicon (Si) counterpart, these devices promise very fast turn-on capabilities as full conductivity modulation occurs >10 times faster than comparable silicon thyristors, low leakage currents at high junction temperatures and at high voltage, and much lower forward voltage drop at high pulse currents. Our progress on the development of large area (4mm x 4mm) SiC thyristors is presented in this paper.
Anti-CD2 (T, p50) intact ricin immunotoxins for GVHD-prophylaxis in allogeneic bone marrow transplantation.

Abstract We evaluated the inhibitory effects of two immunotoxins (IT) synthesized by linking two different anti-CD2 (T, p50) murine monoclonal antibodies (MoAb) to intact ricin (R). Pretreatment with 1000 ng ml −1 35.1-R or OKT 11 a R inhibited PHA-induced T-cell proliferation by 93% and 86%, respectively. At this IT concentration generation of alloreactive cytotoxic T-cells (CTL) was inhibited by more than 99% by either IT. 35.1-R and OKT 11 a were minimally toxic to natural killer (NK) effectors or pluripotent bone marrow progenitor cells (CFU-GEMM). Blocking experiments suggested that 35.1-R and OKT 11 a -R might recognize different epitopes of the CD2 (T, p50) surface determinant. Our findings show that anti-CD2 IT may be useful for T-cell depletion in allogeneic bone marrow transplantation. We compared TU3, an equimolar mixture of T101 [anti-CD5]-R, UCHT-1 [anti-CD3]-R and 35.1 [anti-CD2]-R with the TUT-cocktail (a mixture of T101-R, UCHT-1-R and TA-1 [antiCDwl8]-R. TUT is currently under evaluation in Phase 1 clinical trials as a T-cell depletion regimen for GVHD prophylaxis. TU3 was as effective as TUT-cocktail in inhibition of PHA response and CTL generation but unlike TUT spared NK effectors. Cocktails of immunotoxins directed against subpopulations of lymphocytes may be useful (a) for more effective anti-GVHD strategies, and (b) to circumvent problems of graft failure/rejection associated with current purgation regimens.
Misfit Dislocations in Epitaxial Ni/Cu Bilayer and Cu/Ni/Cu Trilayer Thin Films

Misfit dislocations at the interfaces of bilayer (Ni/Cu) and trilayer (Cu/Ni/Cu) thin films were examined by plan-view transmission electron microscopy (TEM). In the bilayers, the spacing of misfit dislocations was measured as a function of Ni layer thickness. The critical thickness, at which misfit dislocations start to appear with the loss of coherency, was found to be between 2 and 5 nm. The spacing of the misfit dislocations decreased with increasing Ni layer thickness and reached a plateau at the thickness of 30 nm. The minimum spacing is observed to be about 20 nm. A g·b analysis of the cross-grid of misfit dislocations revealed 90° Lomer dislocations of the {001} type lying in the (001) interface plane at a relatively large thickness of the Ni layer, but 60° glide dislocations of the {111} type at a relatively small thickness of the Ni layer. In the trilayers, misfit dislocations formed at both interfaces. The spacing of the misfit dislocation is in agreement with that of the bilayers with a similar Ni layer thickness. The misfit dislocation arrays at the two interfaces, having the same line directions, are 60° dislocations with edge components with opposite signs but are displaced with respect to each other in the two different interface planes. This suggests that interactions of the strain fields of the dislocations have a strong influence on their positions at the interface.
Influence of Hypertonic Saline Solution Infusion on Defibrillation Efficacy

Hypertonic saline solution may enhance cardiac conduction via the fast inward sodium channel and alter transmembrane Ca ++ conductance via the sodium-calcium exchanger. Evidence suggests that both Ca ++ conductance and myocardial conduction velocity may affect ventricular defibrillation. Since hypertonic saline solution solutions (ie, sodium bicarbonate) may be administered to patients who have conditions that often require ventricular defibrillation (ie, cardiac arrest or hypovolemic shock), we studied the effect of hypertonic saline solution on the defibrillation threshold (DFT) in 16 pentobarbital-anesthetized domestic farm swine (20 to 30 kg). Defibrillation was performed using two interfaced epicardial electrode patches. DFTs were determined at baseline and during treatment phase. Pigs were randomly assigned to treatment consisting of either hypertonic saline solution (6 mmol/kg load, 2.0 to 3.0 mmol/kg infusion) to maintain serum sodium concentrations 10 to 15 mmol/L above baseline or control (D5W given in equal volume). DFT values (joules) that predicted 50% success were modeled from a best-fit histogram. Hypertonic saline solution did not change DFT values from baseline values (10.2±4.3 vs 10.8±7.0, respectively). Likewise, placebo (D5W) did not change DFT values from baseline values (10.1±4.5 vs 11.3±4.3). During treatment phase, DFT values were 99±28% of baseline values in the hypertonic saline solution group and 116±23% of baseline values in the D5W groups (p=0.21). The administration of hypertonic saline solution also did not affect ventricular conduction velocity, right ventricular action potential duration, or right ventricular effective refractory period. These data indicate that hypertonic saline solution does not appreciably affect defibrillation efficacy or electrical treatment of ventricular fibrillation.
Sensitivity of ozone concentrations to VOC and NOx emissions in the Canadian Lower Fraser Valley

Abstract The SAPRC90 chemical mechanism module implemented in CALGRID is updated for the specific emissions and applications of the Lower Fraser Valley (LFV) of British Columbia, Canada. The kinetic and mechanistic parameters of lumped VOC reactions recalculated using the LFV emissions profiles are noticeably different from those based on default emissions profiles, indicating the importance of tailoring the parameters to specific regions. The sensitivities of ozone concentrations to total and speciated VOC and NOx emissions as well as to the NO 2 NO x ratios are determined. Significant VOC model species are identified based on the impact of their emissions on ozone formation in the LFV. Of note is the importance of the emissions of a lumped class of aromatics, ARO2, which contains mostly isomers of xylene and trimethylbenzene and is derived chiefly from the use and distribution of gasoline fuels. The ARO2 emissions make the largest contribution of all model VOC species to the ozone levels in the urban plume. The results indicate that reduction of AR02 emissions alone could achieve significant reduction of ozone levels in the LFV. Base case emissions of NOx(NO or NO2) in the LFV contribute negatively to the ozone formation. Any overestimation of NOx or underestimation of VOC in the emissions inventory could cause underestimations of ozone levels by photochemical models.
Initial stages of the interaction of a shock wave with a dust deposit

Abstract The trajectories of solid particles which are raised from a dust deposit after the passage of a weak shock wave are explored by computations and compared with available experiments. A dust particle experiences a lift force on account of the velocity gradient within the boundary layer behind the shock front. An analytical expression by Saffman for this lift force is used in the equation of motion for the particle. The computations show that a particle lifted beyond the shock boundary layer loses lift force, reenters the growing boundary layer, and moves toward the floor. By applying these computations to particles originated from various locations of the floor, an envelope formed by the instantaneous particle positions may simulate the dust profile in the entrainment processes of a dust deposit by a gas stream. The present model shows general good agreement with laboratory experiments under various test conditions.
Usage analysis of a public website reconstruction tool

The Web is increasingly the medium by which information is published today, but due to its ephemeral nature, web pages and sometimes entire websites are often "lost" due to server crashes, viruses, hackers, run-ins with the law, bankruptcy and loss of interest. When a website is lost and backups are unavailable, an individual or third party can use Warrick to recover the website from several search engine caches and web archives (the Web Infrastructure). In this short paper, we present Warrick usage data obtained from Brass, a queueing system for Warrick hosted at Old Dominion University and made available to the public for free. Over the last six months, 520 individuals have reconstructed more than 700 websites with 800K resources from the Web Infrastructure. Sixty-two percent of the static web pages were recovered, and 41% of all website resources were recovered. The Internet Archive was the largest contributor of recovered resources (78%).
Prevention of the organophosphorus neuropathy by glucocorticoids

Abstract The effects of an intensive glucocorticoid regimen on the delayed organophosphorus neuropathy were investigated in the hind limb of cats injected intraarterially with 2 mg/kg diisopropylfluorophosphate (DFP). In this model of a delayed peripheral neuropathy, the animals develop a peculiar high-step gait. This sign initially appears in 14 days and is maximal 21 to 28 days after DFP administration. Concommitantly, the capacity of soleus α-motor nerve terminals to generate repetitive discharges after high-frequency conditioning is severely attenuated. In cats that received an i.v. injection of methylprednisolone (90 mg/kg) 5 to 10 min after DFP administration and seven doses of triamcinolone (8 mg/kg, i.m.) once every 3 days starting on the 2nd day after DFP, no clinical signs of a neuropathy were observed for 70-day intervals. Furthermore, in these glucocorticoid-treated cats administered DFP, the incidence of high-frequency conditioned repetitive discharges was normal. Electromicroscopy showed that the ultrastructure of the neuromuscular junction was normal. Thus, the glucocorticoid regimen protected cats against the delayed neurotoxic effect of organophosphorus poisoning.
Increasing the Robustness of Boosting Algorithms within the Linear-programming Framework

AdaBoost has been successfully used in many signal classification systems. However, it has been observed that on highly noisy data AdaBoost easily leads to overfitting, which seriously constrains its applicability. In this paper, we address this problem by proposing a new regularized boosting algorithm LPnorm2-AdaBoost (LPNA). This algorithm arises from a close connection between AdaBoost and linear programming. In the algorithm, skewness of the data distribution is controlled during the training to prevent outliers from spoiling decision boundaries. To this end, a smooth convex penalty function (l 2 norm) is introduced in the objective function of a minimax problem. A stabilized column generation technique is used to transform the optimization problem into a simple linear programming problem. The effectiveness of the proposed algorithm is demonstrated through experiments on many diverse datasets.
Symmetry relations among pionization cross sections

From Mueller's Regge analysis of the pionization region, symmetry relations to order ${s}^{\ensuremath{-}\frac{1}{4}}$ among invariant cross sections at $x=0$, in which a final pion is observed, are derived. SU(3) and quark universality are assumed to relate the Regge residues at the projectile-Reggeon vertex. There is good agreement with experiment to 10-50% indicating that the approximate symmetry pattern at nonasymptotic energies is that of total cross sections. The rising of the invariant cross sections to their asymptotic forms as $c\ensuremath{-}b{s}^{\ensuremath{-}\frac{1}{4}}$ can be understood in terms of known $j$-plane singularities if the $f$-Pomeron central vertex ${g}_{\mathrm{fP}}^{{\ensuremath{\pi}}^{+}}({{q}_{\ensuremath{\perp}}}^{2})l0$. Symmetry relations valid for final kaons and nucleons and for both the pionization and the target-fragmentation regions are also given.
GrpE, a nucleotide exchange factor for DnaK

The cochaperone GrpE functions as a nucleotide exchange factor to promote dissociation of adenosine 5'-diphosphate (ADP) from the nucleotide-binding cleft of DnaK. GrpE and the DnaJ cochaperone act in concert to control the flux of unfolded polypeptides into and out of the substrate-binding domain of DnaK by regulating the nucleotide-bound state of DnaK. DnaJ stimulates nucleotide hydrolysis, and GrpE promotes the exchange of ADP for adenosine triphosphate (ATP) and also augments peptide release from the DnaK substrate-binding domain in an ATP-independent manner. The eukaryotic cytosol does not contain GrpE per se because GrpE-like function is provided by the BAG1 protein, which acts as a nucleotide exchange factor for cytosolic Hsp70s. GrpE, which plays a prominent role in mitochondria, chloroplasts, and bacterial cytoplasms, is a fascinating molecule with an unusual quaternary structure. The long alpha-helices of GrpE have been hypothesized to act as a thermosensor and to be involved in the decrease in GrpE-dependent nucleotide exchange that is observed in vitro at temperatures relevant to heat shock. This review describes the molecular biology of GrpE and focuses on the structural and kinetic aspects of nucleotide exchange, peptide release, and the thermosensor hypothesis.
Structural and magnetic properties of the novel Nd3Fe29−xTix compound from powder neutron diffraction

Abstract The structure and stoichiometry of a new rare-earth iron-based intermetallic compound Nd 3 Fe 29− x Ti x , has been determined using powder neutron diffraction on a sample with x = 1.24. The structure consists of fifteen unique transition metal sites and two rare-earth sites, in a monoclinic cell of symmetry p 21/ c . The magnetic moments are aligned along the a -axis and the Ti occupies sites with low rare-earth coordination. The structure shows a distinct stacking along the b -direction, consisting of rare-earth-Fe(Ti) layers and layers containing only Fe(Ti).
The neglected role of positive emotion in adolescent psychopathology

Adolescence is a developmental period characterized by elevated stress, heightened risky behaviors, and increases in psychopathology. Emotion dysregulation is a hypothesized contributor to negative outcomes and to the onset of psychopathology during adolescence. However, the dysregulation of negative emotion has been the focus of research while the literature on positive emotion in adolescent psychopathology is limited. This review highlights both the development of normative and dysregulated positive emotion during adolescence. First, the literature on normative adolescent emotional development and on negative emotional regulation is briefly reviewed, followed by a discussion of current theories of positive emotion, which are grounded in the adult literature. From a developmental perspective, the dimension of approach motivation within positive emotion is emphasized throughout and frames the review. This conceptualization guides organization of literatures on normative experiences of positive emotion in adolescence and the role of dysregulated positive emotion in adolescent psychopathology, specifically adolescent depression, anxiety, bipolar disorder, externalizing disorders and eating disorders. Last, future directions in the study of adolescent positive emotion and its regulation and the implications of highlighting approach motivation in normative and dysregulated positive emotion in adolescence are detailed.
Sodium-proton exchange in crayfish.

Abstract Recently, three proton pump inhibitors were shown to have no effect on proton excretion and little on Na uptake in tapwater-adapted (TW) crayfish, while all three reduced Na–H exchange in salt-depleted (SD) animals. It appeared that the exchange was mediated by the Na channel–H pump in SD crayfish but not in TW animals. An alternative, a 2Na–1H exchanger, might function in the latter. To test this, the effects of amiloride (AM) and ethylisopropyl AM (EIPA) on Na fluxes were observed. AM inhibits the Na channel but is a much weaker blocker of Na–H exchangers. In contrast, EIPA inhibits exchangers but acts weakly on the Na channel. If an exchanger functions in TW crayfish, we should expect EIPA to block Na influx in them with AM having a weaker action. The reverse should be true in SD animals. Experimental data showed that EIPA was a potent inhibitor of Na influx in TW crayfish with half-maximal inhibition at about 0.2 μM. However, AM proved to be equipotent. In SD crayfish, EIPA was as effective as in TW animals, and again AM was equally potent. The data fail to show the expected differential action. Therefore, AM and its analogues cannot be used to distinguish between the two models of Na–H exchange in crayfish.
Pentylenetetrazole-induced seizures stimulate transcription of early and late response genes.

Abstract Cellular immediate early gene and neuropeptide gene expression have each been demonstrated to be modulated in hippocampus in response to a variety of seizure-inducing stimuli. In this study, gene transcription for three immediate early genes, c- fos , c- jun and NGFI-A, and three neuropeptide genes, enkephalin, dynorphin and neuropeptide Y, was investigated using nuclear run-on assays following a single injection of the convulsant pentylenetetrazole (PTZ). At 15 min following PTZ injection, only transcription for c- fos was increased. By 6 h following PTZ treatment, transcription for all immediate early genes and for dynorphin and neuropeptide Y was increased; however, this increase was transient in that transcription of all genes returned to control values by 48 h following PTZ treatment. Thus, regulation of immediate early and neuropeptide gene mRNA levels and immunoreactivity occurs, at least in part, at the level of transcription for the genes encoding neuropeptide Y, dynorphin, c- fos , c- jun , and NGFI-A. Moreover, the difference between increased transcription rates reported here and increased mRNA levels reported here and elsewhere suggests that additional post-transcriptional regulation of gene expression occurs in hippocampal neurons.
Hadamard products for generalized Rogers--Ramanujan series

The purpose of this paper is to derive product representations for generalizations of the Rogers-Ramanujan series. Special cases of the results presented here were first stated by Ramanujan in the ''Lost Notebook'' and proved by George Andrews. The analysis used in this paper is based upon the work of Andrews and the broad contributions made by Mourad Ismail and Walter Hayman. Each series considered is related to an extension of the Rogers-Ramanujan continued fraction and corresponds to an orthogonal polynomial sequence generalizing classical orthogonal sequences. Using Ramanujan's differential equations for Eisenstein series and corresponding analogues derived by V. Ramamani, the coefficients in the series representations of each zero are expressed in terms of certain Eisenstein series.
Signal correlation in isotope ratio measurements with mass spectrometry: Effects on uncertainty propagation

Abstract Here the authors argue that the traditional approaches to uncertainty propagation of isotope ratios in mass spectrometry neglect the statistical dependence (correlation) of isotopic signals. It is shown that, in general, mass spectrometric signals of isotopes are correlated. Hence, the uncertainty of isotope ratios can be accurately propagated from their intensities only if signal correlation (covariance) is considered. The discrepancy between the conventionally propagated (with no correlation included) and observed isotope ratio uncertainties is demonstrated using MC–ICP–MS, ICP–TOF–MS and ICP–Q–MS data. This manuscript describes the uncertainty propagation of isotope abundance ratios and ratios of isotope measurements.
Supraclavicular artery island flap (SCAIF) vs free fasciocutaneous flaps for head and neck reconstruction.

ObjectiveAt our institution, the supraclavicular artery island flap (SCAIF) has become a reliable option for fasciocutaneous coverage of complex head and neck (H&N) defects. We directly compare the outcomes of reconstructions performed with SCAIFs and free fasciocutaneous flaps (FFFs), which have not been reported previously.Study DesignRetrospective chart review.SettingTertiary academic medical center.Subjects and MethodsRetrospective review of consecutive single-surgeon H&N reconstructions using fasciocutaneous flaps over 5 years. Reconstructions were divided into 2 groups: SCAIFs and FFFs. Patient demographics, surgical parameters, and outcomes were compared statistically between groups.ResultsThirty-four flaps were used in H&N reconstruction (18 SCAIFs and 16 FFFs). There was no difference in patient demographics, distribution of defects, or follow-up (SCAIF 9.2 vs FFF 15.13 months, P = .65) between the 2 groups. The SCAIFs were larger than the FFFs (164.6 ± 60 vs 111 ± 68 cm2, P < .05) and had shorte...
Biopsy of the Pigmented Lesions

Although new technologies are becoming available to aid in diagnosis, the skin biopsy continues to be the fundamental tool of the dermatologist to evaluate the nature of a pigmented lesion. There are 3 major techniques for the biopsy of a pigmented lesion: shave biopsy, punch/incisional biopsy, and excisional biopsy. This article discusses when to biopsy a pigmented lesion and reviews the different biopsy techniques, with reference to specific clinical scenarios.
17 Watts continuous wave Rubidium laser

A laser diode array pumped continuous wave rubidium laser with slope efficiency of 53%, total optical efficiency of 46% and output power of 17 Watts has been demonstrated.
DANTE GABRIEL ROSSETTI AND THE BURDENS OF NINEVEH

I N HIS LATE PLAY , Sardanapalus (1821), Byron repeatedly presents questions of legacy, as the Assyrian monarch struggles to determine what his reign will mean to future eras. The drama ends with Sardanapalus and his beloved slave, Myrrha, atop a suicidal pyre meant to destroy the palace as the rebellious satraps close in–the pyre also to be the king's final monument, the act by which posterity will remember him. Indeed, he imagines his flaming destruction will produce “a light/To lesson ages, rebel nations, and/Voluptuous princes,” even though “Time shall quench full many/A people's records, and a hero's acts;/Sweep empire after empire, like this first/Of empires, into nothing” (V.i.440–45). In the event, Sardanapalus's last words on the matter come in the form of a satire on the Egyptian pyramids, those proud Ozymandian monuments which time has turned into sites of confusion: [I]n this blazing palace,And its enormous walls of reeking ruin,We leave a nobler monument than EgyptHath piled in her brick mountains, o'er dead kings,Or kine , for none know whether those proud pilesBe for their monarch, or their ox-god Apis:So much for monuments that have forgottenTheir very record! (V.i.480–87)
Bilinear classifiers for visual recognition

We describe an algorithm for learning bilinear SVMs. Bilinear classifiers are a discriminative variant of bilinear models, which capture the dependence of data on multiple factors. Such models are particularly appropriate for visual data that is better represented as a matrix or tensor, rather than a vector. Matrix encodings allow for more natural regularization through rank restriction. For example, a rank-one scanning-window classifier yields a separable filter. Low-rank models have fewer parameters and so are easier to regularize and faster to score at run-time. We learn low-rank models with bilinear classifiers. We also use bilinear classifiers for transfer learning by sharing linear factors between different classification tasks. Bilinear classifiers are trained with biconvex programs. Such programs are optimized with coordinate descent, where each coordinate step requires solving a convex program - in our case, we use a standard off-the-shelf SVM solver. We demonstrate bilinear SVMs on difficult problems of people detection in video sequences and action classification of video sequences, achieving state-of-the-art results in both.
Big genes and little genes and deadlines for transcription

Some deadlines come and go, and the tardy are merely late. But some deadlines have a more exacting consequence, in which all tardy effort is futile. Transcription faces such a deadline — if a cell arrives at mitosis before RNA polymerase completes its sometimes lengthy task of transcribing a gene, then the nascent transcript is aborted. Like the mythical Sisyphus, RNA polymerase begins its task again, all to no avail, unless it meets the next mitotic deadline. From work reported last month by Rothe et al.1, it now seems that the rapid mitotic cycles of an early Drosophila embryo impose deadlines that cannot be met by larger genes. The timing of these cell cycles is thus a biological ‘gene screen’ that precludes expression of large genes at early stages. The synthesis of a transcript is a substantial task. The mammalian RNA polymerase working at its rate of about 3 kilobases (kb) per minute (37 °C) requires roughly 11 hours to traverse the gargantuan (2,000-kb) dystrophin gene. Measurements2,3 of the lag between initiation at a promoter and transcription of downstream sequences have shown that the Drosophila polymerase progresses at about 1.4 kb per minute (25 °C). At this rate, 55 minutes are required for transcription of the Ultrabithorax gene, whereas only 2 are needed for the shorter knirps gene. Are these times of any significance to the function of the genes in the control of early development?
Extensive Tissue Necrosis Following High‐Concentration Sclerotherapy for Varicose Veins

Background.Tissue necrosis after sclerotherapy has been observed, but is unexplained.Objective.To present the complication of extensive tissue necrosis following high-concentration sclerotherapy for varicose veins.Methods.Cases coming to the attention of the authors are presented briefly with commen
Growth dynamics and associated mycorrhizal fungi of little bluestem grass [Schizachyrium scoparium (Michx.) Nash] on burned and unburned sand prairies

SUMMARY WP examined the influence of burning on little bluestem grass productivity and its vesicular-arbuscular mycorrhizal (VAM) fungal associates in a sand prairie community over (bar growing seasons (1586-4). Above-and below-ground productivity was higher on the burned sites than on the unhurried sites. Percent VAM funga1 colonization levels were significantly burned sites than on the unburned sites. In contrast, early in the growing season, colonized and specific rout lengths were longer on the burned site than on the unburned sites but differences were not always significant. Roots of plants on the burned sites supported more fungal biomass than roots on the unburned sites especially during the early growing season. However, colonization d:it;i suggest that the fungi were unable to keep up with the greater below-ground production of plants on the burned prairies. Mycorrhizal inoculum potential levels of little bluestem rooi zone and randomly collected soil and VAM fungal spore densities were lower on the burned sites than the unburned sites during the year of the burn. Above- and below-ground tissue samples showed significantly higher concentrations and accumulations of several inorganic, nutrients on the burned site early and later in the growing season.However, in contrast, plants on the unburned sites had greater nutrient-use efficiencies for several nutrients than plants on the burned sites. Lower nutrient-use efficiencies of plants on burned sites may in pan be due to the onset of harsher environmental conditions during the growing season and/or to associated VAM fungi- VAM fungi associated with plants on the burned sites are likely a carbon drain on these plants, supporting greater fungal biomass, and hence, plants on burned sand prairie sites may not benefit from their VAM fungal association especially early in the growing season.
The neurodevelopmental hypothesis of schizophrenia: Following a trail of evidence from cradle to grave

This is a critical review of the literature related to the neurodevelopmental hypothesis of schizophrenia which posits that the illness is related to abnormal brain development. The review focuses on data deriving from clinical studies, and it is organized according to the life phase from which the data were collected: conception and birth, infancy and childhood up to the onset of the illness, after illness onset, and postmortem. The neurodevelopmental hypothesis is supported by several pieces of evidence, including increased frequency of obstetric complications in patients with schizophrenia: the presence of minor physical anomalies; the presence of neurological, cognitive, and behavioral dysfunction long before illness onset; a course and outcome of the illness itself that is incompatible in most cases with a degenerative illness; the stability of brain structural measures over time; and the absence of postmortem evidence of neurodegeneration. A historical perspective on how this research accumulated and a section addressing important areas of future investigation are also provided. We conclude that schizophrenia is certainly not a degenerative brain disorder, and that it is likely that a brain insult in utero or at birth plays a role in its expression. Current evidence cannot completely exclude the role of environmental variables after birth. In addition, it is possible that other psychiatric disorders may also have a neurodevelopmental component.
Looking back on cocaine dependence: reasons for recovery.

Factors that contributed to long-term recovery from cocaine dependence were examined as part of a 5-year national follow-up study of 708 patients from 45 treatment programs in eight U.S. cities. Outcomes from 33% of the sample were highly favorable at follow-up, including no drugs detected in urine or hair specimens, no self-reported use of any drugs, less than daily alcohol use, and no illegal activity or arrests during the past year. Major reasons cited for these improvements were motivations to change, positive influences of family, strength from religion and spirituality, and help from drug treatment. "Recovery" was viewed as a continuous process and one that benefits from lessons learned in treatment. These retrospective attributions affirm many of the same findings from prospective outcome studies and contribute to a conceptual framework for treatment process and recovery.
Checkpointing for peta-scale systems: a look into the future of practical rollback-recovery

Over the past two decades, rollback-recovery via checkpoint-restart has been used with reasonable success for long-running applications, such as scientific workloads that take from few hours to few months to complete. Currently, several commercial systems and publicly available libraries exist to support various flavors of checkpointing. Programmers typically use these systems if they are satisfactory or otherwise embed checkpointing support themselves within the application. In this paper, we project the performance and functionality of checkpointing algorithms and systems as we know them today into the future. We start by surveying the current technology roadmap and particularly how Peta-Flop capable systems may be plausibly constructed in the next few years. We consider how rollback-recovery as practiced today will fare when systems may have to be constructed out of thousands of nodes. Our projections predict that, unlike current practice, the effect of rollback-recovery may play a more prominent role in how systems may be configured to reach the desired performance level. System planners may have to devote additional resources to enable rollback-recovery and the current practice of using "cheap commodity" systems to form large-scale clusters may face serious obstacles. We suggest new avenues for research to react to these trends.
A physics-based analytical model of a GaN/AlGaN HEMT incorporating spontaneous and piezoelectric polarization

A physics-based charge control model of an AlGaN/GaN high electron mobility transistor (HEMT) has been used to predict large- and small-signal characteristics. The 2DEG concentration in the channel is calculated using the Schrodinger equation in conjunction with the triangular quantum well approximation. Spontaneous and piezoelectric polarizations at the heterointerface and finite effective width of the 2DEG have been incorporated in the analysis. The calculated results are compared with experimental data from an Al/sub 0.15/Ga/sub 0.85/N/GaN HEMT structure to show the agreement. The model predicted a maximum drain current of 523 mA/mm and transconductance of 138 mS/mm for a device of length 1 /spl mu/m and width 75 /spl mu/m. The calculated data is compared against experimental values.
On batch means in the simulation and statistics communities

Batching is a well known technique for estimating the variance of point estimators computed from simulation experiments. The batch statistic variance estimator is simply the (appropriately scaled) sample variance of the estimator computed on subsets of data. The simulation and statistics communities seem to be largely unaware of each other's results in this area. Some empirical and theoretical results from the simulation and statistics literature will be discussed and compared. In particular, we discuss the important issue of selecting batch size and present a new data based method for determining it. The basic idea is to empirically estimate the optimal batch size for a smaller simulation length, and then extrapolate using knowledge of the optimal order of magnitude of batch length for the original simulation length. We provide a small simulation showing the effectiveness of the proposed method.
A scatter and randoms weighted (SRW) iterative PET reconstruction.

Purpose: In positron emission tomography(PET)imaging, the main function of scatter and randoms corrections is to improve contrast and quantitative accuracy. Both corrections are essential and critically important. Several iterative reconstruction schemes incorporating scatter and randoms corrections have been developed over the years. In this work, the authors propose a new method to incorporate the scatter and randoms corrections into the iterative image reconstruction, which has shown promising results in regards to improving reconstruction performance and image quality as compared to the standard methods. Methods: The authors describe a scatter and randoms weighted (SRW) iterative PETreconstruction algorithm. The SRW method is based on the estimation of the trues fraction (TF) within theprompts. Once the TF is estimated, it is then incorporated into the weighting component of the system matrix, and the net result is a scatter and randoms weighting in the sensitivity image similar to the attenuation correction weighting. Although using the measured prompts in the TF estimation was demonstrated to achieve the fastest convergence at high statistics, it is not reliable in low counts situations due to the sparse and noisy nature of the measured prompts. Therefore, a mean estimation of the prompts derived from the forward projection of the reconstructedpromptsimage was introduced into the TF estimation. A contrast phantom was scanned, and the data were reconstructed using the standard and the SRW methods. Results: The contrast vs noise, precision vs accuracy in contrast, absolute error vs number of iterations comparisons, and standard deviation image over different realizations of the same object were evaluated at low counts situations, and it was observed that the SRW method outperforms the standard approaches such as the scatter and randoms data precorrection and the ordinary Poisson methods. The image intensity (activity) outside the object can also be minimized using the SRW method. In addition, further improvement in accuracy, precision, convergence, and noise properties can be achieved by further improving the TF and theprompts estimate. Conclusions: The authors have developed a practical scatter and randoms weighting scheme in the sensitivity image for iterative PETreconstructions. Our proposed SRW method has a number of advantages over the conventional methods, and it has shown promising results with additional optimization for various applications to be further investigated.
Blind identification of FIR channels via antenna arrays

Proposes a new method for blind identification of possibly nonminimum phase FIR channels using antenna arrays. Based on a frequency domain formulation, the authors show that even a nonminimum phase channel driven by stationary sequences can be identified from the second-order statistics. Although in the single antenna case it is necessary to use cyclostationary signals or higher order statistics to identify the magnitude and phase of the channel, the authors circumvent such a requirement by exploiting multichannel properties of the array. They also present necessary and sufficient conditions for channel identifiability, and develop an identification algorithm. >
Psychosine, Cytokinesis, and Orphan Receptors: Unexpected Connections

One of the most exciting aspects of modern cell biology is the potential to make connections between disparate areas of research, and thus open up new lines of enquiry. Two recent papers have done just this ([Kanazawa et al. 2000][1]; [Im et al. 2001][2], this issue). Building on the biochemical
Oscillation in Tuned Radio-Frequency Amplifiers

The wide use of screen-grid tubes renders an understanding of the conditions for stability of tuned radio-frequency amplifiers important. In this paper the relation between the feed-back capacity and the other circuit and tube parameters at the threshold of instability is computed for one, two, three, and four stages. The form of the relation is found to be Ag2 CO = w) gm where g is the conductance of the load circuit and plate resistance in parallel, assuming that all circuits are similar. The values of A are 2.0, 1.0, 0.764, and 0.667, respectively, for one, two, three, and four stages. It is found that the circuits are tuned so that the phase angle of each is approximately 45 deg. lagging, still including the plate resistance of the tube in the tuned circuit. An experimental verification of the conditions for stability of a one-stage amplifier is described. The experimental value checks the theoretical value within the accuracy of the measurements.
Computational method for ranking task-specific exposures using multi-task time-weighted average samples

A method is presented for ranking task-specific exposures using time-weighted average samples collected during the performance of multiple tasks. The task ranking can be used for purposes such as prioritizing further assessment or control. No a priori estimates of the individual task concentration distributions are required. Sample concentrations and task-specific concentrations are assumed to be log-normally distributed, and each known sample concentration is modeled as the geometric time-weighted average of the unknown task concentrations. Since the task durations are usually not known, the task time-weights are estimated as a crude fraction of sampling period. Log transformed sample concentrations are aggregated based on the non-occurrence of each task during some samples, resulting in a set of linear equations which are solved to yield estimates of the log-transformed task median concentrations. The performance of the method was tested under a variety of conditions using simulated sample data. The method was found to yield remarkably reliable ranking of task median concentrations, especially for the high exposure tasks, provided that the number of samples was adequate and the task concentration distributions were not highly overlapped. The performance of the method can be easily modeled using simulated data over the range of plausible task concentration distributions for any number of samples and any job scenario. Even under the conservative assumption that some task concentration distributions are highly overlapped, the assigned ranking can be usefully interpreted in the light of the modeling to determine whether a task is relatively high exposure or low exposure.
LiDAR assisted emergency response: Detection of transport network obstructions caused by major disasters

This article explores whether the use of LiDAR data in detecting transport network obstructions shortens the time required to reach disaster sites. It presents a method for doing this using LiDAR data collected in New Orleans, Louisiana (USA) before and after Hurricane Katrina. It involves identifying all the LiDAR data points that lie within transport links (e.g., highways or streets) and performing blockage detection analysis with the Quick Terrain Modeler (QT Modeler) software. After performing this blockage detection, routing analysis was performed to determine the effect of these obstructions on the time needed to reach 30 randomly chosen locations in the study area from the centrally located City of New Orleans Fire Station. The results show that the use of LiDAR data in emergency response situations can significantly reduce the response times for first responders to reach disaster sites.
Radiation-induced mutation rate and DNA content in Schizosaccharomyces pombe.

Abstract : Data from experiments using a forward mutation system in Schizosaccharomyces pombe following exposure to gamma-rays are reported. When these data were analyzed for mutation rates per locus per rad and normalized for the DNA content of S. pombe, the values obtained were very similar to those predicted by the correlations suggested by Abrahamson et al. This forward mutation system in S. pombe has been extensively used and well characterized.
Another Way of Dealing With Disputes: A Mossi Case

All societies have formal means of settling disputes. An individual may, however, astutely manipulate conflicting institutional rules, especially in the context of rapid culture change and successfully circumvent all jural procedures. In this article a traditional Mossi woman formally changes her social status to that of “Christian” and in so doing enlists the norms of the church to assist her in disposing of an unwanted common-law husband of 5 years in a socially acceptable manner. The rules of the church defined her sexual union as illicit and required that it be terminated if she were to receive baptism. This was precisely the end she had in view, though Mossi custom would have made such a move more difficult and embarrassing.