cssi/SciSciGPT-SciSciNet huggingface dataset:
Direct QR factorizations for tall-and-skinny matrices in MapReduce architectures

The QR factorization and the SVD are two fundamental matrix decompositions with applications throughout scientific computing and data analysis. For matrices with many more rows than columns, so-called “tall-and-skinny matrices,” there is a numerically stable, efficient, communication-avoiding algorithm for computing the QR factorization. It has been used in traditional high performance computing and grid computing environments. For MapReduce environments, existing methods to compute the QR decomposition use a numerically unstable approach that relies on indirectly computing the Q factor. In the best case, these methods require only two passes over the data. In this paper, we describe how to compute a stable tall-and-skinny QR factorization on a MapReduce architecture in only slightly more than 2 passes over the data. We can compute the SVD with only a small change and no difference in performance. We present a performance comparison between our new direct TSQR method, indirect TSQR methods that use the communication-avoiding TSQR algorithm, and a standard unstable implementation for MapReduce (Cholesky QR). We find that our new stable method is competitive with unstable methods for matrices with a modest number of columns. This holds both in a theoretical performance model as well as in an actual implementation.
Angioplasty and stenting of transplant renal arteries: a single-center experience

Purpose A single-center retrospective review was conducted to examine the long-term effects of stenting in renal transplant patients diagnosed with acute, acute on chronic, or chronic kidney dysfunction. Materials and Methods A single center retrospective review was conducted to examine the long-term effects of stenting in patients diagnosed with TRAS resulting in acute, acute on chronic, or chronic kidney disease. Angiography was performed when there was either a clinical suspicion of TRAS or after MRA confirmed moderate to severe stenosis. The clinical diagnosis of TRAS was based on uncontrolled refractory or new-onset hypertension or azotemia and unexplained graft dysfunction in the absence of another diagnosis, such as rejection, obstruction, or infection. Between 12/2003 and 7/2012, 38 patients underwent stenting for TRAS. 24 males and 14 females, average age at stent placement was 56.2 years. Mean change in estimated glomerular filtration rate (eGFR) following intervention was used to determine the clinical success of transplant renal artery angiography and stenting. Results The mean eGFR level in 38 patients with kidney dysfunction was 27.8 ± 12.9 mL/min/1.73 m 2 at the time of diagnosis of TRAS. After all patients were successfully treated with angiography and stent placement, the patients were evaluated six months later. The mean eGFR level increased to 38.0 ± 12.0 mL/min/1.73 m 2 (P = 0.0004), making the mean reduction of 10.2 mL/min/1.73 m 2 within six months statistically significant. Only one of the 38 patients required reintervention. No patient required re-transplantation. Conclusion Transplant renal artery stenosis is a recognized complication of a transplanted kidney resulting in renal insufficiency. Transplant renal artery angioplasty and stenting demonstrates high clinical success with improvement in overall transplant renal function. Further studies are warranted to demonstrate long-term outcomes.
Response to hormones of cells cultured from human giant cell tumors of bone.

Giant cell tumors of bone obtained from 7 patients were dispersed with clostridial collagenase and trypsin and adherent cells were maintained in culture. Early cultures contained both mononucleated and multinucleated cells presumably derived from the stromal and giant cells of the original tumor. The original multinucleated cells did not survive for >7-10 days whereas the mononucleated cells persisted and could be passaged by trypsinization. In 5 of 7 early cultures exposed to parathyroid hormone (PTH) there was a rise in cAMP within 5-10 min in both cellsand medium which averaged # 12-fold. None of the cells responded to calcitonin and a variable rise in cAMP was seen after incubation with prostaglandin E2. In cells cultured from 3 tumors the PTH response disappeared with passage of the cells, but in the remaining 2, PTH response persisted through multiple passages. The presence as well as the magnitude of the PTH-induced cAMP response in these cells is consistent with a skeletal origin.
Direct measurement of H-atom sticking coefficient during diamond film growth

In previous work it has been demonstrated that diamond thin films can be grown in a heated quartz flowtube by adding organic molecules to a stream of atomic hydrogen. In this system, the pattern of diamond film growth may be used to obtain information about the growth kinetics. In the present work, a thin, moveable catalytic probe that detects hydrogen atoms has been added. Since the flowtube is at a uniform temperature and has a high flowspeed, the rate of decay of H-atoms down the tube may be converted to a sticking coefficient, after making a small correction for diffusive mass transfer. The data were taken at a tube temperature of 800 Celsius and a pressure of 3.7 torr, with 1 SCCM of methane injected into a flow of 150 SCCM of 90% argon, 10% hydrogen. Calibration of the H-atom probe indicates that all the hydrogen is initially nearly dissociated. The probe measurements give a sticking coefficient at 800 Celsius of about 3 X 10-4 for the silicon/diamond substrates. During diamond deposition, i.e., when methane is flowing, the apparent sticking coefficient rises to 2.5 X 10-3, although this includes the effect of gas phase reaction as well as wall loss. We will discuss how these numbers shed light on proposed mechanisms for diamond formation.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
The Taxonomy of Diaporthe Cubensis

SUMMARY The taxonomy of Diaporthe cubensis, causal agent of a canker disease of Eucalyptus spp., is discussed in relation to its conspecificity with Endothia havanensis and correct generic affinity. It was concluded that the fungus should be transferred to Cryphonectria.
Modification and characterization of the permanent sympathectomy produced by the administration of guanethidine to newborn rats

The administration of guanethidine to newborn rats has been shown to produce a permanent sympathectomy with potential advantages over immunosympathectomy and 6-hydroxydopamine-induced chemical sympathectomy. In this paper, we report on a revised treatment regimen involving initiation of treatment (50 mg/kg/day) on day 7 after birth and continuing for 3 weeks. Animals treated by this protocol have a low mortality rate (approx. 10% above saline-treated controls) and no permanent growth deficit. Analysis of tyrosine hydroxylase activity in and light microscopic examination of superior cervical ganglia of the guanethidine-treated animals indicate complete destruction of sympathetic neurons by the end of the second week of treatment. During and after treatment there are no decreases in norepinephrine in whole brain of the treated animals. Norepinephrine levels in peripheral tissues are markedly reduced at both 9 and 16 weeks of age. Stimulation of vasomotor outflow produces no increase in blood pressure in guanethidine-treated rats at 9 or 26 weeks of age, indicating a complete and permanent functional denervation of the vasculature. The adrenal glands of the guanethidine-treated animals are not destroyed, but rather respond, apparently by transsynaptic induction, with increases in tyrosine hydroxylase and epinephrine content. Interestingly, despite the continued deprivation of a peripheral sympathetic nervous system in these animals. adrenal tyrosine hydroxylase and epinephrine levels return to control levels by 10 weeks of age. These data indicate that administration of guanethidine to newborn rats produces a very complete and permanent sympathectomy with significant advantages over immunosympathectomy and 6-hydroxydopamine-induced chemical sympathectomy.
CP and P determination and other applications of tau -lepton and t-quark polarimetry.

At an {ital e}{sup +}{ital e}{sup {minus}} collider when the decay {ital X}{r arrow}{ital f{bar f}} occurs, the {ital X} rest frame is often known. We assume here that this is the case and work out symmetry tests in this frame. In this paper the {ital P} and {ital CP} symmetry tests for the decay of integer-spin systems into a pair of vector bosons {ital V}{sub 1}{ital V}{sub 2} are generalized to the {ital X}{r arrow}{bar {tau}}{tau} and {r arrow}{ital t{bar t}} decay modes where the {tau}'s and {ital t}'s decay weakly. Polarization effects are present in {tau} decays and are expected to be in top-quark decays provided {ital m}{sub {ital t}} is not {similar to} {radical}2 {ital m}{sub {ital W}} (113 GeV). They also are expected to occur if other new charged fermions should be discovered. In spite of missing neutrino and antineutrinos in the final state, we find that powerful {ital P} and {ital CP} symmetry tests can be obtained. At hadron colliders the {ital X} rest frame is normally not known. However, these tests may assist or stimulate similar symmetry-test investigations, for example, via Monte Carlo simulations that include the angular momentum properties of the decay process.more » These {tau} and/or {ital t} polarimetry results for {ital P} and {ital CP} determination, for determination of the chiral or helicity structure of {ital f} or {ital X} decay amplitudes, for testing for {ital CP} violation, etc., are of current interest. For example, they should be useful in {ital Z} and {ital Z}{prime} physics and in searches for the top quark and for Higgs bosons.« less
Direct Measurements of an Increased Threshold for Stimulated Brillouin Scattering with Polarization Smoothing in Ignition Hohlraum Plasmas

We demonstrate a significant reduction of stimulated Brillouin scattering by polarization smoothing in large-scale high-temperature hohlraum plasma conditions where filamentation is measured to be negligible. The stimulated Brillouin scattering experimental threshold (defined as the intensity at which 5% of the incident light is backscattered) is measured to increase by a factor of $1.7\ifmmode\pm\else\textpm\fi{}0.2$ when polarization smoothing is applied. An analytical model relevant to inertial confinement fusion plasma conditions shows that the measured reduction in backscatter with polarization smoothing results from the random spatial variation in polarization of the laser beam, not from the reduction in beam contrast.
Delayed degradation of bioabsorbable meniscal fixators

Abstract A greater understanding of the functional importance of the meniscus has prompted a more aggressive approach to conserving meniscal tissue. Multiple treatment options exist when dealing with a tear of the meniscus. As the popularity of bioabsorbable implants in the orthopaedic armamentarium grows, concern exists as to the potential associated complications. We describe a case of the failure of a bioabsorbable meniscal fixator appropriately applied to a posterior medial meniscal tear with an associated injury of the anterior cruciate ligament. Moreover, the concern of implant retention secondary to delayed degradation and resultant potential for articular cartilage damage was present. Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 17, No 3 (March), 2001: pp E11–E11
A new analysis of the effects of the Asian crisis of 1997 on emergent markets

Abstract This work is devoted to the study of the Asian crisis of 1997, and its consequences on emerging markets. We have done so by means of a phase transition model. We have analyzed the crashes on leading indices of Hong Kong (HSI), Turkey (XU100), Mexico (MMX), Brazil (BOVESPA) and Argentina (MERVAL). We were able to obtain optimum values for the critical date, corresponding to the most probable date of the crash. The estimation of the critical date was excellent except for the MERVAL index; this improvement is due to a previous analysis of the parameters involved. We only used data from before the true crash date in order to obtain the predicted critical date. This article's conclusions are largely obtained via ad hoc empirical methods.
On Inhomogeneous Diophantine Approximation

Abstract A new approach to inhomogeneous Diophantine approximation is given and a method for the computation of inhomogeneous minima of binary quadratic forms is derived. The new method is simpler than earlier ones of Barnes and Swinnerton-Dyer. As an application, a new proof of a theorem of Davenport, which gives the complete sequence of inhomogeneous minima for the form x 2 − xy − y 2 , is given.
Penile squamous cell carcinoma (SCC) presenting as inguinal abscess

Introduction: Cancer can rarely present as an abscess. We present a rare case of sterile groin abscess originating from a metastatic cancer.
TopCAT-Topographical Compartment Analysis Tool to analyze seacliff and beach change in GIS

This paper discusses the development of a new GIS extension named the Topographic Compartment Analysis Tool (TopCAT), which compares sequential digital elevation models (DEMs) and provides a quantitative and statistical analysis of the alongshore topographical change. TopCAT was specifically designed for the morphological analysis of seacliffs and beaches but may be applied to other elongated features which experience topographical change, such as stream beds, river banks, coastal dunes, etc. To demonstrate the capabilities of TopCAT two case studies are presented herein. The first case examines coastal cliff retreat for a 500m section in Del Mar, California and shows that large failures comprised a large portion of the total eroded volume and the average retreat rate does not provide a good estimate of local maximum cliff retreat. The second case investigates the alongshore volumetric beach sand change caused by hurricane Bonnie (1998) for an 85km section in the Cape Hatteras National Seashore, North Carolina. The results compare well (generally within 6%) with previous investigations. These case studies highlight additional information gained through performing a detailed, discretized analysis using TopCAT.
Metabolic energy of intact honey bee colonies

Abstract 1. 1. In late winter, oxygen consumption of honey bee ( Apis mellifera L.) clusters showed marked 24-hr periodicity, even when held under constant temperature conditions. 2. 2. Minimal rates of metabolism (as low as 3.4 w kg −1 ) were usually reached at night ( ca . 0500 hr), and maximum rates (as high as 33.5 w kg −1 ) in midday ( ca . 1400 hr). 3. 3. Colonies with brood showed less excursion in daily metabolic rate, by maintaining higher night-time levels. 4. 4. There is a pronounced decrease in metabolic rate for the intact cluster of 9480–23,394 bees from the rates reported for individuals or small groups of bees.
Point:Counterpoint: Supraspinal locomotor centers do/do not contribute significantly to the hyperpnea of dynamic exercise

This series of debates was initiated for the Journal of Applied Physiology because we believe an important means of searching for truth is through debate where contradictory viewpoints are put forward. This dialectic process whereby a thesis is advanced, then opposed by an antithesis, with a
IHI s Amine-Based CO2 Capture Technology for Coal Fired Power Plant

Abstract Amine-based CO 2 capture technology is being developed in order to further reinforce and widen the applications of IHI's CO 2 capture technology. The 20 ton-CO 2 /d pilot plant located at IHI's Aioi Works in Japan is based on the design knowledge acquired from fundamental technology research related to operational evaluation, material evaluation, and plant simulator technology. The pilot plant was constructed and the tests started in June 2012. We have been investigating advanced solvent, process and packing system for reducing consumption energy. We achieved the regeneration energy of the advanced solvent and process to be less than 2.7 GJ/t-CO 2 by using the bench-scale test facility. Although these advanced technologies have been evaluated in laboratory and bench scale, we are planning to evaluate them by using the pilot plant in 2013.
Efficacy and safety of prolonged amlodipine treatment in hypertensive children

To examine the long-term efficacy and safety of amlodipine in hypertensive children, data on prolonged use (≥6 months) of amlodipine in 33 children were reviewed. All children received amlodipine as sole therapy for their hypertension. Causes of hypertension included solid organ transplant (n=19), renal disease (n=7) primary hypertension (n=6), and drug-induced hypertension (n=1). Mean patient age at the start of amlodipine treatment was 9.8±4.8 years (range 1.3–16.9); there were 19 boys and 14 girls. Mean duration of amlodipine treatment was 20.4±11.5 months (range 6–48). Analysis of blood pressure and dosing data revealed that blood pressure reduction was sustained throughout the period of amlodipine treatment, while amlodipine dose remained stable (mean effective daily dose 0.17±0.12 mg/kg). No patient required discontinuation of amlodipine because of adverse effects. This small study suggests that prolonged amlodipine treatment is well tolerated in hypertensive children and provides sustained blood pressure control. Further studies are necessary to determine what effects if any long-term calcium channel blocker treatment has on the growth and development of children with hypertension.
Attachment of Trypanosomacruzi to host cells: A monoclonal antibody recognizes a trypomastigote stage-specific epitope on the gp 83 required for parasite attachment

A set of monoclonal antibodies against the purified surface gp 83 of T. cruzi trypomastigotes was produced and the ability of these monoclonals to inhibit the attachment of trypomastigotes to heart myoblasts was investigated. Western blots of solubilized trypomastigotes, epimastigotes or amastigotes probed with this set of monoclonal antibodies show that the gp 83 is present in invasive trypomastigotes, but not in non-invasive epimastigotes or amastigotes. One monoclonal antibody (Mab 4A4) from this set inhibits the attachment of trypomastigotes to heart myoblasts, whereas the others (MAbs 2H6, 4B9, 2D11) do not. These results show that the Mab 4A4 recognizes an epitope on the gp 83 of invasive trypomastigotes required for parasite binding to host cells.
Hypothalamic-pituitary corticotroph function after shunting of magnocellular vasopressin and oxytocin to the hypophyseal portal circulation

Surgical pituitary stalk compression (PSC) causes neural lobe denervation and development of ectopic magnocellular terminals in the external zone of the median eminence, resulting in shunting of magnocellular vasopressin (VP) and oxytocin (OT) to the pituitary portal circulation. To determine the effects of PSC on hypothalamic and pituitary function, VP and CRH receptors and POMC messenger RNA (mRNA) in the pituitary, and CRH, VP, and OT mRNA levels in the PVN were examined in 7-day PSC and sham-operated rats. Immunohistochemical staining revealed marked accumulation of immunoreactive VP in the swollen pituitary stalk and the external zone of the distal median eminence of PSC rats. Plasma ACTH and corticosterone levels were significantly increased by PSC, an effect that was attenuated by minipump infusion of desamino-[D-Arg8]-vasopressin (DDAVP) given to correct the diabetes insipidus. [3H]VP binding to anterior pituitary membranes from PSC rats was reduced by 50% compared to that in sham-operated controls, but VP V1b receptor mRNA levels measured by in situ hybridization were unchanged. Pituitary CRH receptors measured by binding autoradiography and CRH receptor mRNA levels did not change after PSC. POMC mRNA was unchanged in the anterior pituitary lobe, but markedly increased in the intermediate lobe of PSC rats, with or without DDAVP infusion. In the hypothalamic supraoptic and paraventricular nuclei, PSC resulted in reduction of VP mRNA (-83%) and OT mRNA (-38%) levels, probably reflecting retrograde degeneration of magnocellular neurons. This decrease was more pronounced for VP mRNA than for OT mRNA CRH mRNA levels in parvicellular cells of the paraventricular nuclei of PSC rats were reduced by 55%. Correction of the diabetes insipidus by DDAVP treatment further decreased hypothalamic VP mRNA levels, but restored CRH mRNA to control levels. The data show that continuous exposure of the pituitary to high VP levels from ectopic magnocellular fibers in the median eminence results in VP, but not CRH, receptor loss. Pituitary VP receptor down-regulation and decreased hypothalamic CRH expression are likely to contribute to the reduced corticotroph responsiveness to VP reported in this experimental model.
Comparison of chain (Co) and plane (Zn) dopants on charge transport in YBa2Cu3O7−δ

We report the penetration depth, A, and infrared reflectance of a YBa 2 (Cu 0.97 Co 0.03 ) 3 O 7-δ film from 35 cm -1 to 600 cm -1 and from 10 K to 300 K. Co is a chain dopant in contrast to previous work on Zn which is a plane dopant. The effects of the chain dopants and the plane dopants are similar in the normal state. For example, the reflectance of the 3% Co sample is very similar to 4% Zn sample at 100 K and 300 K. However, in the superconducting state, 3% Co has a high reflectance similar to pure YBa 2 Cu 3 O 7-δ while 4% Zn has a gapless reflectance. The penetration depth of the Co doped sample is close to that of pure YBa 2 Cu 3 O 7-δ while that of the Zn doped film is a factor of five larger.
Popliteal Aneurysm Presenting as Thrombophlebitis of the Lower Extremity: A Case Report

A case of a popliteal aneurysm presenting as a deep vein thrombosis of the lower extremity is reported. Venous insufficiency symptoms, like presenting symptoms of a popliteal artery aneurysm, are an uncommon occurrence but often cause a wrong or delayed diagnosis with severe consequences for limb salvage. The importance of an accurate diagnostic study in any patient with a suspected deep vein thrombosis is emphasized in this report.
Nanosensors: design and application to site-specific cellular analyses

ABSTRACTWe report the development and application of an antibody-based nanoprobe for in situ measurements within a single cell.The nanoprobe has an antibody-based probe targeted to benzopyrene tetrol (BPT), a metabolite of the carcinogenbenzo[a]pyrene (BaP) and the BaP-DNA adduct. Detection of BPT is of biomedical interest since this species canpotentially serve as a biomarker for the monitoring of DNA damage due to BaP exposure and for possible pre-cancerdiagnoses. The measurements were performed on the rat liver epithelial Clone 9 cell line, which was used as the modelcell system. Nanoprobes were inserted into individual cells, incubated five minutes to allow antigen-antibody binding,and then removed for fluorescence detection. Prior to measurements, the cells had been treated with BPT. A concentrationof 9.6 ± 0.2 x 10 -11 M has been determined for BPT in the individual cells investigated. The results demonstrate thepossibility of in situ measurements inside a single cell using an antibody-based nanoprobes.Keywords : nanoprobe, nanosensor, nanotechnology, bioprobe, antibody, benzo[a]pyrene, benzopyrene tetrol,carcinogen, cancer, intracellular measurement
A Hybrid QM−MM Potential Employing Hartree−Fock or Density Functional Methods in the Quantum Region

A hybrid quantum mechanical−molecular mechanical (QM−MM) potential energy function with ab initio and density functional capabilities has been implemented in the CHARMM program. It makes use of the quantum mechanical program CADPAC and the CHARMM molecular mechanics energy function; a GAMESS(US) interface to the CHARMM program was already available. To test the methodology, a series of relatively small systems are studied and comparisons are made of full QM calculations with those from various QM−MM partitions. Both density functional and Hartree−Fock calculations for the quantum region are presented and, where possible, compared with results from previous AM1−MM calculations. For the density functional based QM−MM calculations, the LDA and BLYP functionals were used. The performances of both the density functional and Hartree−Fock based QM−MM calculations compare well with pure quantum calculations. The link atom method was tested by performing a number of QM−MM simulations on the complexes of metal cati...
Associations between minimum wage policy and access to health care: evidence from the Behavioral Risk Factor Surveillance System, 1996-2007.

Objectives. We examined whether minimum wage policy is associated with access to medical care among low-skilled workers in the United States.Methods. We used multilevel logistic regression to analyze a data set consisting of individual-level indicators of uninsurance and unmet medical need from the Behavioral Risk Factor Surveillance System and state-level ecological controls from the US Census, Bureau of Labor Statistics, and several other sources in all 50 states and the District of Columbia between 1996 and 2007.Results. Higher state-level minimum wage rates were associated with significantly reduced odds of reporting unmet medical need after control for the ecological covariates, substate region fixed effects, and individual demographic and health characteristics (odds ratio = 0.853; 95% confidence interval = 0.750, 0.971). Minimum wage rates were not significantly associated with being uninsured.Conclusions. Higher minimum wages may be associated with a reduced likelihood of experiencing unmet medica...
The Matrix of Oppression and Privilege: Theory and Practice for the New Millennium

This article discusses a creative, collaborative model the authors have developed between the Ethnic Studies and Women's Studies programs on their campus that provides a paradigm that other universities around the country might learn from. After situating the program within a historical and national context, this article examines the specific challenges faced within the university setting and offers a range of institutional strategies that have proven successful. The authors examine their collaboration, which consciously mirrors and attempts to implement the growing movement in teaching and research toward an intersectional approach to teaching about privilege and oppression. Within the university context, this framework has been institutionalized within the curriculum as well as the structure of the program. In the new millennium, this framework can serve as a model for other campuses.
An antireflux procedure should not routinely be added to a Heller myotomy

Achalasia is a disease that can only be palliated, not corrected, by surgery. The philosophy at Vanderbilt has been to maximize the relief of dysphagia through myotomy that is measured using intraoperative endoscopy while minimizing the mechanical factors that may increase gastroesophageal reflux. Only a few of our patients (3 [ 13 %] of 24) have developed pathologic reflex after Heller myotomy without an antireflux procedure, and all have been treated medically with excellent results. The addition of an antireflux procedure would inappropriately treat the 87% of patients who have no objective measurement of gastroesophageal reflux. Because gastroesophageal reflux does occur in patients who have undergone Heller myotomy and Dor fundoplication, we have chosen not to add a procedure that may increase dysphagia. Our argument against the routine use of fundoplication rests on the concept that a fundoplication, either total or partial, increases resistance to flow across the LES and therefore decreases symptom relief. Our studies, as well as others, indicate that esophageal clearance is an important aspect of reflux after Heller myotomy, and postoperatively patients with achalasia are more prone to long periods of acid exposure caused by inadequate clearance. Symptoms of GERD in patients with achalasia do not correlate with objective measurements of acid exposure in the esophagus; therefore they cannot be used to follow up patients after Heller myotomy. Gastroesophageal reflux can be a significant problem in patients whether they have undergone Heller myotomy alone or Heller myotomy plus fundoplication. We recommend 24-hour pH studies to monitor acid exposure in the distal esophagus postoperatively to identify pathologic GERD after Heller myotomy. Patients found to have pathologic reflux after Heller myotomy with or without fundoplication should be treated medically. In short, acid reflux after a myotomy can be controlled simply with medication, but dysphagia requires more drastic and potentially hazardous treatment such as pneumatic dilatation or reoperation.
PHYTOREMEDIATION OF METALS: USING PLANTS TO REMOVE POLLUTANTS FROM THE ENVIRONMENT

Phytoremediation uses plants to remove pollutants from the environment. The use of metal-accumulating plants to clean soil and water contaminated with toxic metals is the most rapidly developing component of this environmentally friendly and cost-effective technology. The recent discovery that certain chelating agents greatly facilitate metal uptake by soil-grown plants can make this technology a commercial reality in the near future.
Mechanistic Studies of Electrode-Assisted Catalytic Oxidation by Flavinium and Acridinium Cations

Electrochemical behavior of flavinium (Et-Fl+) and acridinium (Acr+) cations is presented, in order to investigate their activity toward catalytic water oxidation. Cyclic voltammograms of Acr+ and Et-Fl+ in acetonitrile are qualitatively similar, with oxidation peaks at highly positive potentials, and these oxidation peaks depend strongly on the type of the working electrode being used. However, the two model compounds exhibit different behaviors in the presence of water: while Et-Fl+ facilitates electrocatalytic water oxidation through an electrode-assisted mechanism, water oxidation is not accelerated in the presence of Acr+. A comparative study of variable scan-rate cyclic voltammetry, concentration dependence, and spectroelectrochemical behavior of two model compounds suggest that Et-Fl+ and Acr+ exhibit different reaction pathways with the electrode surface. On the basis of the experimental results, a mechanism is proposed to account for the observed differences in electrocatalysis.
Queue-rationed equilibria with fixed costs of waiting

The welfare impact of price controls is examined here in an exchange economy where agents may need to queue in order to make a transaction. Time spent in the queue is an endogenously-determined transaction cost, which agents take as given and which adjusts so as to clear markets when prices are prevented from performing this function. When queuing is required, it enters the household’s decision as a fixed cost, rather than increasing in proportion to the amount of good exchanged, as is far more common in the previous literature. Existence of competitive equilibrium is established for this general equilibrium model. Price controls are shown to cause notable inefficiencies, which differ from those of a proportional cost model. Moreover, in certain environments, price controls will unambiguously harm all individuals relative to a Walrasian equilibrium.
Changes in chemical permeation of disposable latex, nitrile, and vinyl gloves exposed to simulated movement.

Glove movement can affect chemical permeation of organic compounds through polymer glove products. However, conflicting reports make it difficult to compare the effects of movement on chemical permeation through commonly available glove types. The aim of this study was to evaluate the effect of movement on chemical permeation of an organic solvent through disposable latex, nitrile, and vinyl gloves. Simulated whole-glove permeation testing was conducted using ethyl alcohol and a previously designed permeation test system. With exposure to movement, a significant decrease (p ≤ 0.001) in breakthrough time (BT) was observed for the latex (−23%) and nitrile gloves (−31%). With exposure to movement, only the nitrile glove exhibited a significant increase (p ≤ 0.001) in steady-state permeation rate (+47%) and cumulative permeation at 30 min (+111%). Even though the nitrile glove provided optimum chemical resistance against ethyl alcohol, it was most affected by movement. With exposure to movement, the latex glo...
In vitro dissolution of gallstones with MTBE: correlation with characteristics at CT and MR imaging.

The authors undertook a study to determine whether in vitro computed tomography (CT) or magnetic resonance (MR) imaging could enable the prediction of the outcome of gallstone dissolution with methyl tert-butyl ether (MTBE). In vitro CT and MR images were obtained of gallstones removed at surgery from 40 and 30 patients, respectively. The patterns of the gallstones seen on CT scans were categorized as dense, moderately dense, faint, isodense, rimmed, and laminated. Gallstones were categorized by maximal signal intensities seen on T1-weighted MR images. After imaging, gallstones underwent in vitro MTBE dissolution. CT appearances correlated well with dissolution rates. Greatest weight change was noted in gallstones with homogeneously faint and isodense patterns, and least weight change was seen in stones with a homogeneously dense pattern. Rimmed and laminated stones with foci of high attenuation dissolved significantly to 5% or less of the original weight, a finding indicating that such foci do not preclu...
Ultrasonic focusing through inhomogeneous media by application of the inverse scattering problem

A new approach is introduced for self-focusing phased arrays through inhomogeneous media for therapeutic and imaging applications. This algorithm utilizes solutions to the inverse scattering problem to estimate the impulse response (Green’s function) of the desired focal point(s) at the elements of the array. This approach is a two-stage procedure, where in the first stage the Green’s functions is estimated from measurements of the scattered field taken outside the region of interest. In the second stage, these estimates are used in the pseudoinverse method to compute excitation weights satisfying predefined set of constraints on the structure of the field at the focus points. These scalar, complex valued excitation weights are used to modulate the incident field for retransmission. The pseudoinverse pattern synthesis method requires knowing the Green’s function between the focus points and the array, which is difficult to attain for an unknown inhomogeneous medium. However, the solution to the inverse scattering problem, the scattering function, can be used directly to compute the required inhomogeneous Green’s function. This inverse scattering based self-focusing is noninvasive and does not require a strong point scatterer at or near the desired focus point. It simply requires measurements of the scattered field outside the region of interest. It can be used for high resolution imaging and enhanced therapeutic effects through inhomogeneous media without making any assumptions on the shape, size, or location of the inhomogeneity. This technique is outlined and numerical simulations are shown which validate this technique for single and multiple focusing using a circular array.
The Underutilization of Health Services in the Black Community: An Examination of Causes and Effects

This article examines the effects of the institutional legacy of African slavery on the utilization of health services among Blacks. Religiosity, spirituality, and apprehension of Eurocentric insti...
Electric field measurements above thunderstorms

Abstract The electric field and conductivity of the atmosphere were measured above thunderstorms in the central Florida area in a series of twenty-five balloon flights made at altitudes ranging from 70,000 to 90,000 ft above sea level. These tests indicate that at these altitudes and for the storms investigated there is a positive current of approximately 1.3 A, on the average, flowing upward from the top of the thunderstorm toward the ionosphere and confirm Wilson's hypothesis that thunderstorms are the generators which supply the electric current necessary for maintaining the earth's negative charge.
5-2-1-0 goes to school: a pilot project testing the feasibility of schools adopting and delivering healthy messages during the school day.

OBJECTIVE. Our goal was to determine the feasibility of school staff voluntarily adopting strategies to deliver health-promotion messages to primary and middle school students during the school day. METHODS. During the 2006–2007 school year, we provided a resource kit with strategies for promoting physical activity and healthy eating through use of the 5-2-1-0 message (encouraging ≥5 servings of fruits and vegetables daily, limiting screen time to ≤2 hours per day, promoting ≥1 hour of physical activity daily, and avoiding sugar-sweetened beverages) to 7 primary schools and 2 middle schools in southern Maine. Teachers and administrators voluntarily implemented resource-kit strategies in classrooms and schools. The resource kit included educational handouts that could be sent home to parents. Administrators, teachers, and parents were surveyed at the end of the school year to ascertain their level of awareness of the project, ease of implementation, and perceived usefulness of the resource kit. In small discussion groups with students, we assessed their level of awareness of and attitude toward the 5-2-1-0 message. RESULTS. Most administrators and teachers and half of the parents reported being more aware of the 5-2-1-0 message as a result of the project. Eighty percent of the teachers who reported using the resource kit found it easy or extremely easy to use. Ninety percent of the teachers reported that they would be willing to continue implementing strategies in the future; of those who would not, a lack of time was cited as the reason. All administrators reported that the project had been worthwhile for their district. Parents were less aware of the message than teachers and administrators; 2 in 5 parents reported receiving educational handouts. Most students responded positively to the messages. CONCLUSIONS. It is feasible for primary and middle schools to voluntarily deliver health-promotion messages during the school day through implementing strategies from the 5-2-1-0 resource kit. For school staff to fully implement the strategies, time constraints, both real and perceived, need to be addressed.
Course-Integrated Information Literacy Instruction in Introduction to Accounting

Two groups of students, enrolled in Introduction to Accounting, volunteered to participate in a pedagogical study to assess course-integrated information literacy instruction. Only one group had received information literacy instruction in an earlier business course. Academic librarians provided three instruction sessions, and students completed a semester-long case to evaluate a company as a potential investment. The results suggest that information literacy skills can be learned for application in subsequent coursework. This research also provides some evidence of significantly greater improvement in information literacy and significantly higher perceptions of course-integrated instruction benefits by students who had not received the previous instruction.
The relative biological effectiveness of I-125 and Pd-103

Purpose : To determine the relative biological effectiveness (RBE) of I-125 and Pd-103 relative to Co-60. Methods and Materials : A cell line REC :ras, derived from rat embryo cells, was used. Cells in exponential or plateau phase were irradiated at dose rates of about 0.07 Gy/h and 0.14 Gy/h. To circumvent the interface effect, cells were grown and irradiated on membranes made of cellulose acetate, which has an effective Z of 7.5. I-125 and Pd-103 seeds were placed in a custom designed template that yielded a homogeneous dose distribution in the plane of the cell culture. The dose rates of irradiation were measured by calibrated thermoluminescence dosimetry (TLD) chips. Results and Conclusions : Our measurements yielded an RBE of about 1.4 for I-125 at dose rates of about 0.07 Gy/h, and an RBE of about 1.9 for Pd-103 at dose rates of about 0.07 Gy/h and 0.14 Gy/h. The RBE of I-125 is similar to those measured by other investigators, the RBE for Pd-103 is being reported for the first time.
Potential Habitat of Acropora spp. on Florida Reefs

Abstract Elkhorn and staghorn corals ( Acropora palmata, Acropora cervicornis ) were listed as threatened species under the Endangered Species Act in 2005. The decline of these species beginning in the late 1970s is unprecedented given the vital role they historically played as major builders of western Atlantic and Caribbean coral reefs. The goal of this study was to create potential-habitat maps for A. palmata and A. cervicornis that would show areas in which these species currently exist, as well as areas that would be suitable for their (re)establishment, using a database of reported in situ observations and existing mapped data. Using the mapped coral reef and hardbottom classifications throughout the Florida reef tract, potential-habitat maps were generated using buffers that incorporated 95% and 99% of reported observations of colonies of Acropora spp. The potential-habitat maps were produced based on benthic substrates throughout the Florida reef tract using GIS software. Locations of 99% of A. palmata observations and 84% of A. cervicornis observations coincided with previously mapped coral reef or hardbottom habitat. These results indicate that potential habitat for A. palmata is currently well defined and that potential habitat for A. cervicornis is more variable and has a wider range than that for A. palmata . This study provides a novel method of combining datasets at various geographic spatial scales and may be used to inform the current NOAA critical habitat map. One of the most important differences between the current NOAA critical habitat map and the new potential-habitat map is observed in the southeast Florida region, where A. cervicornis appears to be thriving outside of mapped reef areas and at latitudes considered marginal for hermatypic corals. Thus, the potential habitat extends further north than the previous critical habitat - and encompasses additional habitat for A. cervicornis and potentially for A. palmata .
Integration of CFD and condensation polymerization chemistry for a commercial multi-jet tubular reactor

Abstract This paper discusses a reactor model for simulating single-phase turbulent reacting flows in a commercial multi-jet tubular condensation polymerization reactor. The model integrates momentum, mass and energy balance equations using commercial computational fluid dynamics (CFD) software with a built-in finite-rate/eddy-dissipation formulation to describe turbulence–chemistry interactions. The turbulence fields are obtained using the standard k– e model. Sensitivity analysis is used to identify the key reactions of importance in the poorly micromixed region. Results include visualization of velocity, pressure, concentration (with and without chemical reactions), and temperature distributions in the reactor. The propensity to form high polymer mass and foul near the reactor inlet is studied for a range of operating conditions. In contrast to the non-reacting CFD conclusion that lower operating rates improve mixing efficiency, the present analysis illustrates how fouling problems can limit operation at lower rates. This analysis may also be used to design reactor internals that maximize performance and operating flexibility.
125I-ligand for progesterone receptor: 17α-(6'-iodohex-1'-ynyl)-19-nortestosterone

Progesterone receptor (PgR) is known to be a significant indicator of hormone dependency of a breast tumor and also an important prognostic factor for recurrence and survival. Relatively low specific activity of tritium-labeled ligands makes it difficult to detect the presence of PgR in very small specimens and in specimens with low PgR content. We therefore undertook the synthesis of a radioiodinated progestin. We have synthesized unlabeled 17 alpha-(omega-haloalk-1'-ynyl)-19-nortestosterones with 4, 6, and 8 carbon side chains; these have high affinity for PgR and clear potential for conversion to a 125I form. Since the six-carbon side chain analogue had the highest relative PgR affinity (38% of the affinity of R5020, using PgR from T47D human breast cancer cells), it was selected for preparation of the 125I form by radiohalogen exchange of a omega-bromoalkynyl precursor with carrier-free Na125I. This new ligand was found by Scatchard analysis to have a Kd of 0.47 nM, as compared with [3H]R5020 at 0.22 nM and [3H]progesterone at 2.0 nM. (For affinity studies, all ligands were diluted in dimethylformamide and added to PgR-containing T47D cytosol to give a final DMF concentration of 4%, in order to prevent R5020 and the test compounds from binding nonspecifically to proteins and glass/plasticware.) The new 125I-ligand showed very little instability when stored in ethanol at approximately 10 degrees C even for several months. Thus, 17 alpha-(6'-[125I]iodohex-1'-ynyl)-19-nortestosterone should prove to be a useful ligand for high sensitivity PgR assays.
N-terminal amino acid sequences of Azotobacter vinelandii and Rhodospirillum rubrum flavodoxins†

Summary The amino-terminal sequences of A. vinelandii and R. rubrum flavodoxins have been determined. These proteins have larger molecular weights (mw≅23,000) than do other flavodoxins for which sequences have previously been reported (mw≅14,000). A comparison of these results with those obtained in other laboratories for P. elsdenii, C. pasteurianum, C. MP and D. vulgaris flavodoxins shows that significant homology exists in the FMN phosphate binding site region in all of these flavoproteins. Furthermore, the sequences reveal relationships among these various proteins which correlate with properties such as riboflavin binding ability and visible circular dichroism spectra.
Selected anthropometric measurements of Akwesasne Mohawk youth: skinfolds, circumferences, and breadths.

Nationally, Native American youth have been shown to be at risk for overweight, and an increased prevalence of obesity among Native American children has been consistently reported. We describe skinfolds, circumferences, and body breadths to assess body size and shape of Akwesasne Mohawk youth (n = 271) between the ages of 10.0 and 16.99. Akwesasne is a sovereign nation with territory in New York state and Canada. Sex- and age-specific comparisons were made to reference values published from the Advance Data from Vital and Health Statistics and from the Third National Health and Examination Survey (NHANES III). Akwesasne youth have thicker skinfolds and larger circumferences than youth in the national surveys. Additionally, these cross-sectional data indicate that body fat is more centrally distributed in Akwesasne Mohawk boys and girls. Given the numerous studies emphasizing the importance of body fat distribution as a risk factor for chronic, obesity-related diseases prevalent within Native American communities, and the high level of fatness presented in this study, more concerted efforts need to be applied to help reduce the development of overweight in children from an early age. Am. J. Hum. Biol. 19:525–536, 2007. © 2007 Wiley-Liss, Inc.