cssi/SciSciGPT-SciSciNet huggingface dataset:
Efficient Formation of Iron Nanoparticle Catalysts on Silicon Oxide by Hydroxylamine for Carbon Nanotube Synthesis and Electronics

Iron containing nanoparticles are found to spontaneously form on hydroxylated SiO2 substrates when immersed in a freshly mixed aqueous solution of FeCl3 and hydroxylamine. Upon calcination, a submonolayer of uniformly distributed iron oxide nanoparticles can be derived and used to catalyze the growth of single-walled carbon nanotubes by chemical vapor deposition. This simple method affords clean single-walled nanotube films on SiO2. The solution phase catalyst deposition approach allows for submicron scale catalyst patterning. Patterned growth of nanotubes with this catalyst retains high degrees of surface cleanliness and leads to arrays of nanotube electronic devices including field effect transistors. The population of hydroxyl groups on SiO2, reaction time, and pH of the solutions are found to be important to the deposition of nanoparticles through a surface-mediated hydroxylamine/FeCl3 chemistry.
A note on the discovery of technetium

Abstract A careful study of the history of the element 43 covering a period of 63 years since 1925 reveals that there is no reason for believing that the Noddacks and Berg have discovered element 43.
Performance of PCR-Based Assays Targeting Bacteroidales Genetic Markers of Human Fecal Pollution in Sewage and Fecal Samples

There are numerous PCR-based assays available to characterize human fecal pollution in ambient waters. Each assay employs distinct oligonucleotides and many target different genes and microorganisms leading to potential variations in assay performance. Performance comparisons utilizing feces and raw sewage samples are needed to determine which assays are best suited for expensive and time-consuming field validation, fate, transport, and epidemiology studies. We report the assessment of five end-point PCR and 10 real-time quantitative PCR (qPCR) assays that target genes from presumptive Bacteroidales microorganisms reported to be associated with human feces. Each assay was tested against a reference collection of 54 primary influent sewage samples collected from different geographical locations across the United States and 174 fecal DNA extracts from 23 different animal sources. Experiments indicate that human-associated genetic markers are distributed across a broad range of human populations but show substantial differences in specificity for human feces suggesting that particular assays may be more suitable than others depending on the abundance of genetic marker required for detection and the animal sources impacting a particular watershed or beach of interest.
Acid Ceramidase Promotes Nuclear Export of PTEN through Sphingosine 1-Phosphate Mediated Akt Signaling

The tumor suppressor PTEN is now understood to regulate cellular processes at the cytoplasmic membrane, where it classically regulates PI3K signaling, as well as in the nucleus where multiple roles in controlling cell cycle and genome stability have been elucidated. Mechanisms that dictate nuclear import and, less extensively, nuclear export of PTEN have been described, however the relevance of these processes in disease states, particularly cancer, remain largely unknown. We investigated the impact of acid ceramidase on the nuclear-cytoplasmic trafficking of PTEN. Immunohistochemical analysis of a human prostate tissue microarray revealed that nuclear PTEN was lost in patients whose tumors had elevated acid ceramidase. We found that acid ceramidase promotes a reduction in nuclear PTEN that is dependent upon sphingosine 1-phosphate-mediated activation of Akt. We were further able to show that sphingosine 1-phosphate promotes formation of a complex between Crm1 and PTEN, and that leptomycin B prevents acid ceramidase and sphingosine 1-phosphate mediated loss of nuclear PTEN, suggesting an active exportin-mediated event. To investigate whether the tumor promoting aspects of acid ceramidase in prostate cancer depend upon its ability to export PTEN from the nucleus, we used enforced nuclear expression of PTEN to study docetaxel-induced apoptosis and cell killing, proliferation, and xenoengraftment. Interestingly, while acid ceramidase was able to protect cells expressing wild type PTEN from docetaxel, promote proliferation and xenoengraftment, acid ceramidase had no impact in cells expressing PTEN-NLS. These findings suggest that acid ceramidase, through sphingosine 1-phosphate, promotes nuclear export of PTEN as a means of promoting tumor formation, cell proliferation, and resistance to therapy.
Working-Class Jobs and New Parents' Mental Health.

Little research has explored linkages between work conditions and mental health in working-class employed parents. The current study aims to address this gap, employing hierarchical linear modeling techniques to examine how levels of and changes in job autonomy, job urgency, supervisor support, and coworker support predicted parents' depressive symptoms in a sample of 113 dual-earner couples interviewed five times across the transition to parenthood. Increases in job autonomy and decreases in job urgency predicted fewer depressive symptoms in fathers at 1 year postpartum. For mothers, coworker support predicted fewer depressive symptoms, and supervisor support mitigated the negative effects of job urgency on depressive symptoms. Higher work hours coupled with low job urgency predicted declines in mothers' depressive symptoms across the first year of parenthood. Our findings suggest that interventions that lead to greater autonomy, less job urgency, and more supportive work relations may enhance employee well-being among working-class families.
Strength and fracture of amorphous and partially crystallized selenium

The role of spherulitic crystallization on strength and fracture of the elemental glass-former selenium was investigated. Partially crystallized selenium samples having various sizes and volume fractions of spherulites were obtained by heat-treating amorphous selenium at 62, 82 and 100° C for different lengths of time. The flexure strength of partially crystallized selenium decreases with increasing size of spherulites. Scanning electron microscopy of fractured specimens showed that fracture nucleated in the peripheral regions of the spherulites.
Striving for Mutual Collaboration The Case of Mountain University and the Westside

The ability to navigate complex challenges that arise when universities, schools, and communities collaborate with each other is an increasingly important characteristic for effective educational leaders to possess. This case focuses on the planning process that occurred when Mountain University and its neighboring schools and communities attempted to work together for reciprocal benefit. With its use of the work of Paulo Freire, this case can be used to develop discussion on the role of educational leaders in the development of university-school-community partnerships that are mutually dependent on the input of all participants.
Electron Localization in Metallic Quasicrystals

Bulk icosahedral-quasicrystalline aluminum-palladium-rhenium alloys of high structural quality and thermal stability are found to exhibit low-temperature electrical resistivities that are four orders of magnitude larger than those found in disordered metals and metallic glasses. Experiments suggest that these quasiperiodic alloys, which have a semimetallic electron density, are insulators at low temperature. The findings are discussed in light of theories on electron localization and band-gap formation in ordered metallic systems.
Tunneling in the C2HH2 reaction at low temperature

Abstract Low-temperature experiments on the ion—molecule reaction between HN+3 and H2 show that this reaction can occur with an appreciable rate at very low temperature ( ⪡ 100 K) despite the existence of an activation energy barrier. Theoretical calculations have confirmed the mechanism for the process at low temperature to involve tunneling. Although very-low-temperature neutral—neutral reactions between radicals and H2 have yet to be studied in the laboratory, it is possible that such reactions can also proceed via tunneling under activation energy barriers. We estimate a non-negligible rate for the reaction between the radical CCH and H2 at very low temperatures.
Dispersed fluorescence spectroscopy and fluorescence lifetime measurements of excited vibrational levels of CdCH3

Abstract Laser-induced excitation and dispersed fluorescence spectra (originating from the 0 0 , 2 1 and 3 1 vibrational levels of the A electronic state) of jet-cooled CdCH 3 are presented and assigned. The observation of emission from these levels is a result having important implications for the dynamics of photodissociation of Cd(CH 3 ) 2 . Fluorescence lifetimes for emission from the 0 0 , 2 1 and 3 1 vibrational levels are also presented.
A Parallel Non-Alignment Based Approach to Efficient Sequence Comparison using Longest Common Subsequences

Biological sequence comparison programs have revolutionized the practice of biochemistry, and molecular and evolutionary biology. Pairwise comparison of genomic sequences is a popular method of choice for analyzing genetic sequence data. However the quality of results from most sequence comparison methods are significantly affected by small perturbations in the data and furthermore, there is a dearth of computational tools to compare sequences beyond a certain length. In this paper, we describe a parallel algorithm for comparing genetic sequences using an alignment free-method based on computing the Longest Common Subsequence (LCS) between genetic sequences. We validate the quality of our results by comparing the phylogenetic tress obtained from ClustalW and LCS. We also show through complexity analysis of the isoefficiency and by empirical measurement of the running time that our algorithm is very scalable.
Magnetic Moments of the Baryons

The anomalous magnetic moments of the baryon octet are calculated in broken $\mathrm{SU}(3)$ symmetry using low-energy pole dominance as a dynamical model and keeping only the lowest lying intermediate states, the psuedoscalar-meson---baryon states. By using dispersion theory, the anomalous moments are related to an energy integral over the ${S}_{\frac{1}{2}}$ and ${P}_{\frac{1}{2}}$ photomeson production amplitudes, which at low energy and for vanishing meson mass are exactly given by the pole terms. From this exact information we calculate the low-energy contribution to the anomalous moments, keeping all orders in baryon and meson mass splittings and using the $\mathrm{SU}(3)$-symmetric strong-coupling constants. We are able to account for the dominant contribution to the proton and neutron magnetic moment and find in addition, for an $\frac{F}{D}$ ratio\ensuremath{\sim}0.6, that $K(\ensuremath{\Lambda})\ensuremath{\sim}0.4K(n)$, in agreement with the observed value. The $\mathrm{SU}(3)$ predictions for the other moments and the ${\ensuremath{\Sigma}}^{0}\ensuremath{\rightarrow}\ensuremath{\Lambda}+\ensuremath{\gamma}$ transition moment are found to be more badly violated.
The use of spinal angiography in the management of posterior mediastinal tumors: case series and review of the literature.

Abstract Introduction Resection of inferiorly located posterior mediastinal tumors can be complicated by their proximity to the artery of Adamkiewicz (AKA). Although uncommon, intraoperative injury to the AKA may result in paraparesis or paralysis secondary to spinal cord ischemia. The use of preoperative spinal angiography may serve as a useful adjunct to the surgeon in guiding extent of resection of the tumor to avoid injury to this critical artery. Methods After IRB approval (H-31712), three patients, from 2008 to 2011, with lower posterior mediastinal tumors were identified. Their charts were reviewed for information concerning preoperative imaging, operative details, and postoperative neurologic complications. The literature regarding imaging of the AKA, cases of injury in pediatric patients, and recommendations for treatment after its injury were reviewed. Results One patient, who did not have preoperative spinal angiography, developed transient paresis lasting 6weeks after posterior mediastinal tumor resection. Two patients underwent preoperative spinal angiography with successful localization of the AKA. In both cases, the patients subsequently underwent posterior mediastinal tumor resection without injury to the artery and without postoperative neurologic sequelae. Conclusions Preoperative spinal angiography may serve as a useful adjunct in the evaluation of children with inferior posterior mediastinal tumors in order to delineate the relationship of the artery of Adamkiewicz to the tumor for the purpose of guiding surgical resection.
Transient power system analysis with measurement-based gray box and hybrid dynamic equivalents

The paper addresses practical capabilities of artificial neural networks (ANNs) in developing measurement-based continuous-time dynamic equivalents for power systems. Our method is based on a set of measurements at boundary nodes between a subsystem that is to be modeled in detail ("retained" portion of the system) and the part that is to be replaced by a simplified ("equivalent") model. We are particularly interested in combining standard physics-based models with signal-based models derived from measurements. We utilize a color-coding scheme to distinguish between physics-based models (clear or white box) at one end, the signal-based models (opaque or black box) at the opposite end, and mixed (gray box) models in the middle. The paper also proposes a way for combining classical and ANN-based equivalents in a hybrid model implemented in a standard software environment for transient analysis (in this case, ETMSP). Our conclusions are based on simulations performed on a model of a benchmark multimachine power system derived from the WSCC system.
Selection against chromosome aberrations in human lymphocytes

THE frequency of chromosome aberrations in the lymphocytes of people who have been exposed to ionizing radiation decreases for many years, beginning some 2–3 weeks after irradiation, at a rate that depends on the type of aberration1,2. Differences in the rates at which the various types of aberration are eliminated are probably caused by differences in the selection against these aberrations at cell division. No data, however, have been reported on the probability that a given aberration in a human lymphocyte will survive cell division. In this communication we present such data obtained in vitro, together with some new data on the elimination of aberrations in vivo. The two sets of data suggest that the lymphocyte, when stimulated to divide in vivo, will undergo several successive divisions.
A high performance computing framework for physics-based modeling and simulation of military ground vehicles

This paper describes a software infrastructure made up of tools and libraries designed to assist developers in implementing computational dynamics applications running on heterogeneous and distributed computing environments. Together, these tools and libraries compose a so called Heterogeneous Computing Template (HCT). The heterogeneous and distributed computing hardware infrastructure is assumed herein to be made up of a combination of CPUs and Graphics Processing Units (GPUs). The computational dynamics applications targeted to execute on such a hardware topology include many-body dynamics, smoothed-particle hydrodynamics (SPH) fluid simulation, and fluid-solid interaction analysis. The underlying theme of the solution approach embraced by HCT is that of partitioning the domain of interest into a number of subdomains that are each managed by a separate core/accelerator (CPU/GPU) pair. Five components at the core of HCT enable the envisioned distributed computing approach to large-scale dynamical system simulation: (a) the ability to partition the problem according to the one-to-one mapping; i.e., spatial subdivision, discussed above (pre-processing); (b) a protocol for passing data between any two co-processors; (c) algorithms for element proximity computation; and (d) the ability to carry out post-processing in a distributed fashion. In this contribution the components (a) and (b) of the HCT are demonstrated via the example of the Discrete Element Method (DEM) for rigid body dynamics with friction and contact. The collision detection task required in frictional-contact dynamics (task (c) above), is shown to benefit on the GPU of a two order of magnitude gain in efficiency when compared to traditional sequential implementations. Note: Reference herein to any specific commercial products, process, or service by trade name, trademark, manufacturer, or otherwise, does not imply its endorsement, recommendation, or favoring by the United States Army. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Army, and shall not be used for advertising or product endorsement purposes.
The Needs and Concerns of Students during the Sport Management Internship Experience

(2004). The Needs and Concerns of Students during the Sport Management Internship Experience. Journal of Physical Education, Recreation & Dance: Vol. 75, No. 2, pp. 25-29.
A finite newton method for classification

A fundamental classification problem of data mining and machine learning is that of minimizing a strongly convex, piecewise quadratic function on the n -dimensional real space R n . We show finite termination of a Newton method to the unique global solution starting from any point in R n . If the function is well conditioned, then no stepsize is required from the start and if not, an Armijo stepsize is used. In either case, the algorithm finds the unique global minimum solution in a finite number of iterations.
Development of synapses between chick retinal neurons in dispersed culture.

Morphological criteria allow several kinds of synapse to be recognized in the vertebrate retina. It is, however, not presently known if, or how, these morphological differences reflect physiological distinctions. Since a proper investigation of synaptic physiology in the intact retina is compromised by technical difficulties, we have examined dispersed cultures to discover if they are likely to provide a more tractable physiological preparation. The chief question addressed here concerns the extent to which normal synaptic development takes place in the impoverished conditions of dispersed cell culture. Cultures were established from embryonic day 8 chick retina and fixed for microscopy on embryonic equivalent (E.E.) days 12, 14, 16, and 18. Neuronal processes appeared shortly after plating and continued to increase in number and extent through E.E. 16. Cone cells were recognizable by virtue of their distinctive oil droplets. Two classes of cone could be distinguished on the basis of the density of their cytoplasmic staining. Presynaptic ribbons could be observed in cone cells on E.E. 12, but characteristic dyad and triad postsynaptic organization was seldom present at this stage nor was it often observed at subsequent times. An increase in the number of ribbon synapses in culture was seen on E.E. 18. These synapses may represent those of bipolar cells. Conventional synapses were found at all times examined but the number of these increased greatly between E.E. 14 and 16. Of these conventional synapses, we found some whose anatomy was characteristic of synapses made by amacrine cells as well as some whose anatomy was characteristic of synapses made by bipolar cells.
G.P.110 The DUX4 promoter is preferentially expressed in FSHD-affected tissues

Abstract Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal dominant disorder with a one in 7500 incidence. Symptoms typically arise in young adulthood and most patients show clinical features before age 30. FSHD is most commonly characterized by progressive wasting and weakness of facial and shoulder-girdle muscles, although no consistent pattern of penetrance or severity exists, even within affected families. The hallmark characteristic of FSHD is asymmetrical muscle weakness. There are also non-muscular features including retinal vasculopathy and high frequency hearing loss. The pathogenic mechanisms underlying FSHD have been difficult to discern, and scientists in the field have spent most of the last two decades attempting to decipher FSHD pathogenesis. Several recent breakthroughs now support a model in which mis-expression of the myotoxic DUX4 gene is a primary pathogenic event underlying FSHD. We recently showed that DUX4 is generally toxic to muscles, and we therefore hypothesized that there was a direct correlation between DUX4 expression patterns and the involvement of only selected muscles (and ear and retinal pathologies) in FSHD. In short, we proposed that if DUX4 over-expression is indeed the underlying pathogenic event in FSHD, it must be preferentially expressed in FSHD-affected regions. To test this hypothesis, we developed transgenic reporter mice containing a putative DUX4 promoter cloned upstream of GFP. We generated three separate lines of DUX4 promoter-GFP mice. We found the DUX4 promoter directed GFP expression in the face and limbs of newborn and adult mice, as well as the retina and inner ear. Essentially all other organs were GFP negative. Strikingly, all lines showed asymmetrical expression and variable penetrance, even within individual litters. We conclude that our mice faithfully recapitulate expected DUX4 expression patterns in regions of FSHD pathology, and further support the role of DUX4 as pathogenic insult in FSHD.
Fluctuations and transport in a reversed field pinch edge plasma

Edge fluctuations are characterized and their associated transport is determined from Langmuir probe measurements in the ZT-40M reversed field pinch. It is found that the fluctuations have high normalized amplitudes and |n|/n = 0.4). There are significant contributions from magnetic perturbations acting on the equilibrium gradients. Compared to the global estimates, the fluctuation driven particle flux is large, whereas the corresponding electron energy flux is not. In the limiter shadow, the equilibrium density and electron temperature scale lengths are shorter and the fluctuation levels are higher. The fluctuation driven particle flux in the limiter shadow is 60% less than that in the plasma edge; most of the reduction is in the low frequency spectral region, which is where global MHD magnetic fluctuations are strongest.
Effect of pin depth on the dislodgement of pin-retained composite resin crown bases

Abstract A laboratory study was carried out to evaluate the effect of pin depth into dentin on the retention of composite resin crown bases. The crown bases were subjected to laterally applied dislodging forces. The results showed no statistically significant difference at the 95% confidence level in the retention of crown bases retained with pins embedded at 1, 1.5, 2, and 3 mm depth in dentin.
Monohydride and dihydride formation at Si(100) 2x1: A high resolution electron energy loss spectroscopy study

Abstract Results from EELS and LEED investigations on the interaction of atomic hydrogen with the Si(100) 2x1 surface give direct evidence for the formation of two distinct surface phases: a monohydride Si(100) 2x1:H and a dihydride Si(100) 1x1::2H phase. Temperature and exposure time determine which of the two phases appears. An analysis of normal vibrational modes leads to an identification of hydrogen adsorption complexes in both phases.
Collection development in library and information science at ARL libraries

Purpose – This paper seeks to discuss the results of a 2010 survey of LIS selectors at ARL institutions/libraries that do not support an ALA‐accredited program to learn how and why LIS materials are collected at these institutions.Design/methodology/approach – Collection development librarians completed a survey that asked them to describe their institution's selection policies, practices, and budgets for LIS materials, along with their roles as LIS selectors/subject specialists.Findings – LIS collections primarily support librarians and staff in their daily work and ongoing professional development. However, most libraries' LIS collections budgets are comparatively small, selectors receive few requests for new materials, and collecting parameters vary by institution, but are limited in terms of subject, publisher, and audience. The majority of LIS selectors are also responsible for collection development in multiple subject areas and most engage in work outside collection development.Originality/value – ...
Rationality-based beliefs affecting individual's attitude and intention to use privacy controls on Facebook: An empirical investigation

Online social networking sites like Facebook provides a fast and easy way to connect with friends and family. Users need to post and share their personal information in order to get the best possible experiences on Facebook. However, the spreading of private information can also lead to serious and harmful issues. Therefore, privacy becomes an important component in the use of Facebook and it is the user's responsibility to protect his or her profile. This study draws upon the theory of planned behavior and the rational choice theory to investigate the rationality-based beliefs affecting individual's attitude and intention to use privacy controls on Facebook. The results show that individual's attitude toward using privacy controls is influenced by benefit of using privacy controls, cost of using privacy controls, and cost of not using privacy controls. Further, benefits of using privacy controls is shaped by beliefs regarding intrinsic benefit and resource safety; cost of not using privacy controls is shaped by beliefs regarding resource vulnerability, threat severity, privacy risk and privacy intrusion; and cost of using privacy controls is shaped by beliefs about intrinsic cost and work impediment. Theoretical and practical implications of the findings are discussed in the paper.
To What Degree Can Potable Water Foster International Economic Development and Sustainability? What Role Does Health Play?

Governments, international organizations, and practitioners have long proclaimed that investments in potable water supply and sanitation and improvements in public health lead to economic development in the developing world. Unfortunately, scholars have not been able to quantify these relationships for a plethora of reasons. This study found significant, positive relationships between investments in integrated projects of potable water supply combined with sanitation and public health and economic development. The study also moderately supported the hypothesis that the relationship between investments in such projects and economic development is stronger in the presence of better health. The article concludes with hopes that the strength of the findings could encourage greater international investment to promote rural sustainability. In particular, the findings buoy calls for supporting indigenous organizations based in rural areas with integrated methodologies that encourage consciousness-level raising i...
CVP under uncertainty and the manager's utility function

Cost-volume-profit analysis has focused on the firm's short-run output decision assuming that the manager maximizes the firm's objective function rather than his or her own. This study argues that the decision problem facing the manager is to determine not only the level of output, but also the level of investment in risky assets in such a way that the expected utility of the manager's own end-of-period wealth can be maximized when the manager's wealth function is dependent on vested interests both within and outside of the firm, possibly in competition with the firm. Through analytical work, it is demonstrated that a change in fixed costs of the firm affects not only the production decision of a manager, but also his orher decision to invest in risky assets. The direction of this fixed cost effect depends on the particular type of risk aversion displayed by the manager. From the analytical work, five propositions are developed for empirical investigation in the future.
Computational studies of turbulent merger of corotational vortices

A computational study has been conducted to gain a better understanding of the criteria governing the merger of corotating vortices. The zero-equation and one-equation turbulent-flow models are used to model the interaction of two rolled-up, corotational vortices. A model appropriate for the swirling flow under consideration has been proposed to prescribe the algebraic variation of mixing-length in the flow field. The unsteady, two-dimensional equations in a cross-plane are solved for primitive variables using an implicit finite-difference code. The computed downstream merging distances are in good agreement with available wind tunnel data.
Restoring eelgrass, Zostera marina L., habitat using a new transplanting technique: the horizontal rhizome method

Abstract Using a technique we call the ‘horizontal rhizome method’, we recently transplanted 2.52 ha of eelgrass in the Great Bay Estuary, New Hampshire, to mitigate for port expansion impacts to an existing eelgrass population. The project represents the largest, most northerly eelgrass transplanting ever attempted on the east coast of the United States. For our revised method, we created a planting unit (PU) by overlapping the rhizomes of two eelgrass shoots in opposite directions and securing them horizontally into the sediment with a bamboo staple. A variation of the bare-root technique, the horizontal rhizome method reduces the number of plants required by up to 80%, has less impact on the donor site, and provides survival rates that equal or exceed that of other methods. One-year survival rates at three subtidal transplant sites were 75–95% for 1993 transplants, and were 98–99% at four of the five subtidal sites planted in 1994. One-year survival rates varied tremendously; low percent survivals resulted from ice damage at all intertidal sites and animal disturbance at some subtidal sites. We found that intertidal transplanting in this tidally dynamic estuary was not successful (sites had 0–15% survival). Sea ice damage, in conjunction with tidal action, caused this lack of success, although natural intertidal eelgrass beds occur both up- and down-estuary of our transplant sites. At the less successful subtidal sites, low survival rates of 1–5% resulted from disturbance of newly transplanted shoots by crabs and clam worms. Overall survival rates for subtidally transplanted eelgrass using the horizontal rhizome method equalled or exceeded those reported for other methods. Shoot density at one transplant site (234 shoots m−2 ± SE 52.0) exceeded that of the control site (162 shoots m−2 ± 20.6) within 1 yr of transplanting. Shoot density at all subtidal transplant sites surpassed that of the control site (100 shoots m−2 ± 11.6) within 2 yr. The horizontal rhizome method is a successful, minimum-impact technique for large scale eelgrass transplanting efforts in a northern New England cold water environment.
Ventricular tachycardia due to sustained bundle branch reentry: Diagnostic and therapeutic considerations

We have identified bundle-branch reentry (BBR) as the mechanism of ventricular tachycardia (VT) during electrophysiologic studies in 48 patients at our institution. All but three patients had significant structural heart disease, that is, dilated ischemic or idiopathic cardiomyopathy, the most common of anatomic substrates. Syncope and sudden death were the modes of presentation in up to 70% of these patients. The critical prerequisite for the development of this arrhythmia is conduction delay in the His-Purkinje system, which was present in all patients and manifests as a nonspecific conduction delay or a left bundle-branch block (LBBB) in the surface electrocardiogram (ECG) and a prolonged HV interval in the intracardiac recordings. VT with an LBBB morphology is the most common form of BBR, present in 98% of patients. Transcatheter ablation of the right bundle branch (RBB) with the use of radiofrequency current is the treatment of choice, as it effectively eliminates BBR. During long-term follow-up, recurrent tachycardia due to BBR was not documented in any patient; however, congestive heart failure was a common cause of death in this population.
A Bayesian approach to the transmission/disequilibrium test for binary traits

The transmission/disequilibrium test (TDT) for binary traits is a powerful method for detecting linkage between a marker locus and a trait locus in the presence of allelic association. The TDT uses information on the parent-to-offspring transmission status of the associated allele at the marker locus to assess linkage or association in the presence of the other, using one affected offspring from each set of parents. For testing for linkage in the presence of association, more than one offspring per family can be used. However, without incorporating the correlation structure among offspring, it is not possible to correctly assess the association in the presence of linkage. In this presentation, we propose a Bayesian TDT method as a complementary alternative to the classical approach. In the hypothesis testing setup, given two competing hypotheses, the Bayes factor can be used to weigh the evidence in favor of one of them, thus allowing us to decide between the two hypotheses using established criteria. We compare the proposed Bayesian TDT with a competing frequentist-testing method with respect to power and type I error validity. If we know the mode of inheritance of the disease, then the joint and marginal posterior distributions for the recombination fraction (θ) and disequilibrium coefficient (δ) can be obtained via standard MCMC methods, which lead naturally to Bayesian credible intervals for both parameters. Genet. Epidemiol. 22:41–51, 2002. © 2002 Wiley-Liss, Inc.
Braid groups, infinite Lie algebras of Cartan type and rings of invariants

Abstract In this paper we show that each element α of the pure braid group Pn or the pure symmetric automorphism group H(n) of the free group Fn of rank n can be represented as α= exp (D)= id +D+(D 2 /2!)+(D 3 /3!)+⋯ , where D=D(α) is an element of an infinite-dimensional Lie algebra h (n) . Each such D is a derivation of the power series ring C [[a 1 ,…,a r ]] , r=n2−n, which fixes the volume form a1∧⋯∧ar and so h (n) is a subalgebra of Sn2−n, the special Lie algebra of Cartan type. There is a corresponding action of these groups on C [[a 1 ,…,a r ]] and C [a 1 ,…,a r ] . We use the representation α=exp(D) to prove results about the ring of invariants for this action of the pure braid group. The Lie algebra h (n) is a subalgebra of a graded Lie algebra h (n) ; we also calculate the Poincare series of the Lie algebra l (n) and of certain of its subalgebras, and show that these Poincare series are rational.
Chronic Granulomatous Disease of Childhood : Surgical Considerations

Abstract Experience with 25 cases of chronic granulomatous disease of childhood seen at the University of Minnesota Hospitals is reviewed. A unique combination of granulomatous, suppurative disease is commonly encountered in lymph nodes, lung, liver, bones, skin, and other parenchymatous organs. Early definitive excisional drainage or extirpation of the involved organ has proved successful in the control of infection in these patients and the concept of en bloc resection of all infected tissue is presented. The unique combination of granuloma formation and suppuration that coexists in areas of infection in these children seems to justify this approach to therapy that is unresponsive to conventional antibiotics.
Combined analyses of O2 and CO2 for studying the coupling of photosynthesis and respiration in aquatic systems

To simultaneously elucidate patterns of photosynthesis and respiration in aquatic systems, we developed a new gas-switching system for coupled measurements of dissolved metabolic gases. The methodology involves two gas chromatography columns to perform multiple gas separations. The first example using 24 h bottle incubations in estuarine waters showed a 1:1 molar relationship for the coupling between CO2 and O2 in closed systems during photosynthesis and respiration. In a second, open system application using depth-stratified sampling on the Louisiana continental shelf, deviations from this 1:1 relationship between CO2 and O2 were common. In surface waters, depletion of CO2 exceeded excess O2, likely owing to different gas-exchange rates with the atmosphere. In bottom waters, CO2 accumulation could surpass O2 losses, indicating anaerobic respiration. At intermediate depths, CO2 and O2 dynamics followed the 1:1 relationship that was observed in the closed incubations. This approach clearly showed that CO2 ...
Preserved left ventricular twist and circumferential deformation, but depressed longitudinal and radial deformation in patients with diastolic heart failure

Aims To examine myocardial deformation and rotation in patients with heart failure, and elucidate the underlying mechanisms that account for normal ejection fraction (EF) in patients with diastolic heart failure (DHF). Methods and results Fifty consecutive patients presenting with congestive heart failure (age: 58 ± 16 years) underwent simultaneous right heart catheterization and transthoracic echocardiography. Left ventricular (LV) volumes, mass, EF, meridional, and circumferential wall stress were measured in addition to haemodynamic measurements. 2-D speckle tracking was applied to measure longitudinal, radial, and circumferential strain and twist. Twist was reduced only in patients with systolic heart failure (SHF: 5 ± 2°, DHF: 13 ± 6°, control: 14 ± 5°, P 0.05), though it was significantly lower in patients with SHF (−7 ± 3%, P < 0.05). Importantly, longitudinal (DHF:−12%, SHF: −4%, control: −19%, P < 0.001) and radial (DHF: 28 ± 9%, SHF: 14 ± 8%, control: 47 ± 7%, P < 0.001) strains were significantly lower in both heart failure groups than in controls, and were depressed to a larger extent in SHF patients than in those with DHF (both P < 0.05). Conclusion LV longitudinal and radial strains are reduced, but circumferential deformation and twist are normal in DHF patients. On the other hand, in patients with SHF, longitudinal, radial, and circumferential deformation, and twist are all reduced. Multivariable regression analysis suggests that preserved LV twist and circumferential strain may contribute to normal EF in patients with DHF.
Ensemble Coordination for Discrete Event Control

An ensemble is a collection of independent processes, each tasked with drawing potentially differing conclusions about the same data. Using Petri nets, this paper formally describes how ensembles are organized and their behavior coordinated to effect distributed discrete event control of an ocean turbine prototype. Compositions, duals, reverses, and cliques formed over known Petri net graphs comprise the building blocks of the proposed ensemble coordination strategy. The behavior of an ensemble of controllers tasked with fault triage are subject to constraints formulated herein. The controller tasked with prognosis and health management (PHM) itself uses an ensemble of classifiers to detect faults. This ensemble is subject to constraints imposed by stream processing, which require a non-blocking form of rendezvous synchronization. Furthermore, results from each classifier must be fused in a manner that rewards that classifier's ability to predict faults. We identify two competing merit schemes -- one based on individual classifier performance and the other on performance of the sub-ensembles to which that classifier participates. Finally, we model check these Petri nets and report their results.
An X-band Luneburg Lens antenna fabricated by rapid prototyping technology

In this paper, a 3-D Luneburg Lens has been designed, fabricated and characterized. Refractive index control of the lens is based on the mixing ratio of air voids and a polymer. The 12 cm (4λ 0 at 10 GHz) diameter lens is designed to work at X-band. The effective permittivity of the unit cell is estimated by effective medium theory and calculated by the finite-element simulation software Ansoft HFSS. Fabrication is implemented by a polymer jetting rapid prototyping method. In the measurement, the lens antenna is fed by an X-band waveguide. The half-power beam width of the antenna is 14 degrees and no obvious side lobe is found in the measurement above the noise floor.
In vitro organogenesis and plant regeneration from leaves of Solanum candidum Lindl., S. quitoense Lam. (Naranjilla) and S. sessiliflorum Dunal

Adventitious shoots and roots were regenerated from leaf segments of 3 Solanum species: S. candidum Lindl., S. quitoense Lam. and S. sessiliflorum Dunal. Leaf explants differentiated shoots on modified MS medium supplemented with 23-163 µm kinetin and 0-5.7 µm indoleacetic acid (IAA). Excised shoots were induced to form roots by transfer to media with benzyladenine (BA) and naphthaleneacetic acid (NAA) at 0.09 and 0.11/2 µM respectively for S. qultoense and 0.01 µm NAA for S. candidum and S. sessiliflorum. Adventitious roots were produced directly from leaf explants with 0-140 µm kinetin and 0-5.7µm IAA in combination. Rooted plants were successfully established in the greenhouse.
The safety of nanosized particles in titanium dioxide– and zinc oxide–based sunscreens

Given the increasing incidence and prevalence of skin cancer, dermatologists are more frequently recommending sunscreens to their patients. However, the safety of titanium dioxide and zinc oxide nanosized particles in the majority of sunscreens has come under scrutiny from governments and the general public. We sought to characterize the use, safety, and regulatory state of nanosized particles in titanium dioxide and zinc oxide in sunscreens based on studies and position statements from 1980 to 2008. Although we found no evidence of significant penetration of titanium dioxide and zinc oxide nanosized particles beyond the stratum corneum, further studies must be done to simulate real-world conditions particularly in sunburned skin and under ultraviolet exposure.
β-d-Phosphogalactoside Galactohydrolase from Streptococcus cremoris HP: Purification and Enzyme Properties

beta-d-phosphogalactoside galactohydrolase (beta-PGal) was isolated and purified from cell-free extracts of Streptococcus cremoris HP to apparent homogeneity to gel electrophoresis. Using the chromogenic o-nitrophenol-beta-d-galactopyranoside-6-phosphate as substrate, the purified enzyme exhibited a specific activity of 18.71 U/mg of protein and K(m) and V(max) values of 5.88 x 10(-4) M and 23.8 mumol of o-nitrophenol liberated per min per mg of protein, respectively. d-Galactose-6-phosphate was a weak competitive inhibitor of beta-PGal. Activity was relatively heat resistant and was maximal from pH 5.0 to 8.0 and over a temperature range of 45 to 52 C. Dithiothreitol, ethylenediaminetetraacetic acid, and citrate stimulated beta-PGal activity, whereas Mg(2+), Li(1+), and p-hydroxymercuribenzoate were inhibitory. Molecular weight of the enzyme was estimated at 6.76 x 10(4). Amino acid composition was similar to other beta-phosphogalactosidases previously investigated, with the exception that the S. cremoris enzyme contains a small amount of half cystine.
Molecular dynamics studies of nanoconfined water in clinoptilolite and heulandite zeolites

The complete periodic series of alkali and alkaline earth cation variants (Li+, Na+, K+, Rb+, Cs+, Mg2+, Ca2+, Sr2+, and Ba2+) of clinoptilolite (Si : Al = 5) and heulandite (Si : Al = 3.5) aluminosilicate zeolites are examined by large-scale molecular dynamics utilizing a flexible SPC water and aluminosilicate force field. Calculated hydration enthalpies, radial distribution functions, and ion coordination environments are used to describe the energetic and structural components of extra-framework species while power spectra are used to examine the intermolecular dynamics. These data are correlated to evaluate the impact of ion–zeolite, ion–water, and water–zeolite interactions on the behavior of nanoconfined water. Analysis of the correlated data clearly indicates that the charge density of extra-framework cations appears to have the greatest influence on librational motions, while the anionic charge of the framework (i.e.Si : Al ratios) has a lesser impact.
The future of learning and teaching

One of the reasons that providing instructional leadership will be so difficult in the future is that our concepts of schooling and teaching must change fundamentally. Just a few observations serve to give substance to this generalization. First, what the school does in educating the young appears to be less or, at best, no more potent than other factors determining what the child learns and becomes. What the child brings to school from his own home and what he encounters there from other homes seem to add more to learning than what the school itself puts in. Second, the incidence of nonpromotion, dropouts, alienation, and minimal learning in school is such that one is led to conclude that today's schools are obsolescent. They were designed for a different culture, a different conception of learners and of learning, and a different clientele. We do not plan for and deal with our clientele nearly as well as the Cadillac agent plans for and deals with his. Third, success in school, as measured by grades, appears to bear little relationship to good citizenship, good work habits, compassion, happiness, or other significant values in the larger human sphere. Fourth, a relatively new medium--television--has entered into the business of transmitting a major segment of our culture to the young. If the years before beginning school are taken into account, television occupies more hours than schooling during the eighteen years from birth to completion of high school. There are few signs that school and
Complexes acyclic up to integral closure

In [R] D. Rees introduced the notions of reduction and integral closure for modules over a commutative Noetherian ring and proved the following remarkable result. Let R be a locally quasi-unmixed Noetherian ring and I an ideal generated by n elements. Suppose that height (I) = h. Then the ith module of cycles in the Koszul complex on a set of n generators for I is contained in the integral closure of the ith module of boundaries for i > n − h. This result should be considered a dimension-theoretic analogue of the famous depth sensitivity property of the Koszul complex demonstrated by Serre and Auslander-Buschsbaum in the 1950s. At roughly the same time, Hoschster and Huneke introduced the notion of tight closure and thereafter gave a number of theorems in the same (though considerably broader) vein for tight closure. In particular, in [HH] they showed that if R is an equidimensional local ring of characteristic p > 0, which is a homomorphic image of a Gorenstein ring, then for all i > 0, the ith module of cycles is contained in the tight closure of the ith module of boundaries for any complex satisfying the so-called standard rank and height conditions (see the definitions below). Since the tight closure is contained in the integral closure for such rings, the result of Hochster and Huneke extends (in characteristic p) considerably the result of Rees. In fact, their result could be considered a dimension-theoretic analogue of the Buchsbaum-Eisenbud exactness theorem ([BE]), which in a certain sense is the ultimate depth sensitivity theorem. Moreover, using the technique of reduction to characteristic p, Hochster and Huneke have shown that their results hold in equicharacteristic zero as well, whenever the tight closure is defined.