bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Ground State of the One-Dimensional Ising Chain
Authors: Jennings B. K. , Bhaduri R. K. 
Published: October 2017

We consider a linear spin 1/2 Ising chain with pair interactions extending up to the nth neighbor. The following general theorem is proved: 'The energy of any arbitrary spin sequence may be written as a linear sum of cluster energies, the upper limit of the number of Ising spins in a cluster being 2n'. The term cluster energy here is used to mean the energy of a group of spins in a certain configuration, evaluated as if the same configuration repeated itself throughout the chain. The structure of the ground state of the system is investigated using the above theorem. It is shown that the ground state is a repetition of a certain cluster, and that the upper limit of the cluster size is 2n, except for some specific combinations of the interaction strengths when the ground state may admit mixing of different clusters. The possible ground state configurations are worked out explicitly for n = 2, 3, and 4 in the absence of the magnetic field using the above theorem. Previous attempts were confined only up to n = 3.
L Subshell Fluorescence Yields and Coster–Kronig Transition Rates at Z = 88 and 94
Authors: Campbell J. L. , McNelles L. A. , Geiger J. S. , Graham R. L. , Merritt J. S. 
Published: October 2017

The L2 and L3 subshell fluorescence yields, ω2 and ω3, and the Coster–Kronig transition probability f23 in 88Ra and 94Pu have been deduced from conversion electron L X-ray coincidence measurements. The Chalk River [Formula: see text]-spectrometer was used to select the conversion electrons. X rays were detected in a Si(Li) counter which was calibrated for absolute X-ray detection efficiency. The results are as follows: [Formula: see text]
Some Thermodynamic Properties of Pure and Impure Nitrogen
Authors: Ancsin J. 
Published: October 2017

Boiling points, freezing points, and vapor pressures (from 56 K to the normal boiling point) for pure and various doped N2 samples have been measured. The normal boiling points for N2 and N2 doped with 100 v.p.p.m. of O2, Ar, Kr, and CO impurities were found to be 77.3439 K, 77.3458 K, 77.3452 K, 77.3454 K, and 77.3444 K respectively. The triple points of the same samples are 63.14635 K, 63.1445 K, 63.14575 K, 63.1487 K, and 63.14675 K respectively. The values obtained for the heats of sublimation, vaporization, and fusion at the triple point of pure N2 were 6773.8, 6049.6, and 724.3 J/mole respectively and the above impurities changed these quantities by the amounts given in Tables 5 and 6.
Transfer of Electronic Excitation between the 72P1/2 and 72P3/2 States of Cesium Induced by Collisions with Cesium Atoms
Authors: Pace Paul W. , Atkinson J. B. 
Published: October 2017

The method of sensitized fluorescence has been employed to investigate the [Formula: see text] excitation transfer processes in cesium induced in collisions with ground state cesium atoms. The cesium vapor density was kept sufficiently low to enable the cross sections for the mixing process to be determined under single collision conditions and to ensure that radiation trapping and quenching were negligible. A nitrogen laser pumped dye laser was used to excite the cesium atoms to each of the 72P levels in turn and measurements of the relative intensities of fluorescence yielded the following cross sections: [Formula: see text] These results are consistent with the empirical relationship between the magnitude of the cross sections and the fine structure splitting that has previously been determined for the alkalis.
Electron Precipitation at an Auroral Latitude – Saskatoon, L = 4.4. I. Photometer, Magnetometer, and Radiowave Data
Authors: Khan Z. M. , Manson A. H. 
Published: October 2017

A study of the quiet and disturbed lower ionosphere (60–100 km) near solar maximum years (1970–1971) has been carried out at Saskatoon (52 °N, 106 °W, L = 4.4) using a variety of techniques: a 5577 Å photometer, a magnetometer, a 'partial reflection radiowave system' (2.2 MHz), and an all-sky camera. Good correspondences between local and planetary magnetic disturbances and the green line intensity I(5577 Å) have been found. Radiowave data, ordered in terms of I(5577 Å), have been used in seasonal epoch analyses for the four seasons. It is shown that after the photometric maxima near geomagnetic midnight, ionospheric disturbances below 80 km continue to increase in magnitude towards sunrise. They are evident until at least noon the following day. For a given level of I(5577 Å), the ionospheric disturbance (< 90 km) is largest during the night hours in summer and winter; and after sunrise, largest in winter and fall months. There is good general correspondence between these results, and fluxes of precipitated electrons measured by satellite techniques.
Calcul et mesure des forces et couples appliqués à un cristal uniaxe traversé par l'onde extraordinaire
Authors: Roosen Gérald , Imbert Christian 
Published: October 2017

We derive from the Maxwell tensor the forces and torques applied to a uniaxial anisotropic crystal when an extraordinary wave passes through it, and we show that the momentum to be associated with the wave in the crystal is collinear with the Poynting vector. Next, we present experimental results of torque measurements using, successively, two uniaxial anisotropic crystals placed inside a variable pressure container. We finally compare our results with those obtained by other authors and show that, according to the types of experiments, either Abraham's or Minkowski's momentum density will appear. [Translated by the journal]
Absorption Spectrum of the SiC2 Radical in the Gaseous Phase
Authors: Verma R. D. , Nagaraj S. 
Published: October 2017

The stellar spectrum of certain N type stars in the blue–green region has been observed in the laboratory in absorption using the flash discharge technique. It has been interpreted as a 1Π ← 1Σ transition of the linear Si–C–C molecule. A new vibrational analysis has been proposed, which yields the following fundamental frequencies in cm−1. [Formula: see text] The 1Π state shows a small Renner splitting (εω2 = 3.3 cm−1). In addition, 001 and 040 levels are shown to perturb each other due to a Fermi resonance.
Saturation inhomogène des colorants dans le cas d'une excitation incohérente
Authors: Mourou G. , Denariez-Roberge M. M. 
Published: October 2017

A theoretical model is developed here which describes the evolution of hole burning in solutions when the pulse duration is assumed to be longer than the transverse relaxation time T2. The double influence of T2 on the width of the initial hole and also on the transient nature of this hole is observed. A comparison of these results with some experimental measurements is performed.
Thin Sample Time Domain Reflectometry for Nonideal Dielectrics
Authors: Springett B. E. , Bose T. K. 
Published: October 2017

The theoretical time response is derived for a pulse reflected from a thin sample of dielectric situated in a coaxial line. The dielectric is assumed to have a distribution of relaxation times. Specific account is taken of the finite rise time of the applied pulse. The equations developed are general and permit the interpretation of measurements without the necessity of transforming to the frequency domain. Explicit equations are developed for the Cole-Davidson and Cole-Cole representations of nonideal dielectrics. Some experimental examples are discussed to assess the utility of the technique.
Statistical Modeling of Extreme Precipitation with TRMM Data
Authors: Demirdjian Levon , Zhou Yaping , Huffman George J. 
Published: October 2017

AbstractThis paper improves upon an existing extreme precipitation monitoring system that is based on the Tropical Rainfall Measuring Mission (TRMM) daily product (3B42) using new statistical models. The proposed system utilizes a regional modeling approach in which data from similar locations are pooled to increase the quality of the resulting model parameter estimates to compensate for the short data record. The regional analysis is divided into two stages. First, the region defined by the TRMM measurements is partitioned into approximately 28 000 nonoverlapping clusters using a recursivek-means clustering scheme. Next, a statistical model is used characterize the extreme precipitation events occurring in each cluster. Instead of applying the block maxima approach used in the existing system, in which the generalized extreme value probability distribution is fit to the annual precipitation maxima at each site separately, the present work adopts the peak-over-threshold method of classifying points as extreme if they exceed a prespecified threshold. Theoretical considerations motivate using the point process framework for modeling extremes. The fitted parameters are used to estimate trends and to construct simple and intuitive average recurrence interval (ARI) maps that reveal how rare a particular precipitation event is. This information could be used by policy makers for disaster monitoring and prevention. The new method eliminates much of the noise that was produced by the existing models because of a short data record, producing more reasonable ARI maps when compared with NOAA’s long-term Climate Prediction Center ground-based observations. Furthermore, the proposed method can be applied to other extreme climate records.
Treatment of acute migraine attacks in children with analgesics on the World Health Organization Essential Medicines List: A systematic review and GRADE evidence synthesis
Authors: Jeric Milka , Surjan Nives , Jelicic Kadic Antonia , Riva Nicoletta , Puljak Livia 
Published: October 2017

Background The World Health Organization Essential Medicines List (WHO EML) contains two analgesics for treatment of acute migraine attacks in children, ibuprofen and paracetamol. Methods The Embase, CDSR, CENTRAL, DARE and MEDLINE databases were searched up to 18 April 2017. We analyzed randomized controlled trials (RCTs) and systematic reviews (SRs) that investigate the efficacy and safety of ibuprofen or paracetamol for treatment of acute migraine attacks in children. We conducted meta-analysis and assessments of evidence with GRADE, Cochrane risk of bias tool, and AMSTAR. Results Three RCTs (201 children) and 10 SRs on ibuprofen and/or paracetamol for acute migraine attacks in children were included. Meta-analysis indicated that ibuprofen was superior to placebo for pain-free at 2 h or pain relief at 2 h, without difference in adverse events. There were no differences between paracetamol and placebo, or ibuprofen and paracetamol. Ten SRs that analyzed various therapies for migraine in children were published between 2004 and 2016, with discordant conclusions. Conclusion Limited data from poor quality RCTs indicate that ibuprofen and paracetamol might be effective analgesics for treating migraine attacks in children. Inclusion of ibuprofen and paracetamol as antimigraine medicines for children in the WHO EML is supported by indirect evidence from studies in adults.
Association between insulin resistance and preeclampsia in obese non-diabetic women receiving metformin
Authors: Balani Jyoti , Hyer Steve , Syngelaki Argyro , Akolekar Ranjit , Nicolaides Kypros H , Johnson Antoinette , Shehata Hassan 
Published: October 2017

Objectives To examine whether the reduced incidence of preeclampsia in non-diabetic obese pregnant women treated with metformin is mediated by changes in insulin resistance. Methods This was a secondary analysis of obese pregnant women in a randomised trial (MOP trial). Fasting plasma glucose and insulin were measured in 384 of the 400 women who participated in the MOP trial. Homeostasis model assessment of insulin resistance (HOMA-IR) was compared in the metformin and placebo groups and in those that developed preeclampsia versus those that did not develop preeclampsia. Results At 28 weeks, median HOMA-IR was significantly lower in the metformin group. Logistic regression analysis demonstrated that there was a significant contribution in the prediction of preeclampsia from maternal history of chronic hypertension and gestational weight gain, but not HOMA-IR either at randomisation ( p = 0.514) or at 28 weeks ( p = 0.643). Conclusions Reduced incidence of preeclampsia in non-diabetic obese pregnant women treated with metformin is unlikely to be due to changes in insulin resistance.
Real-world monitoring of direct oral anticoagulants in clinic and hospitalization settings
Authors: Takatsuki Seiji , Kimura Takehiro , Sugimoto Kazutaka , Misaki Sadaya , Nakajima Kazuaki , Kashimura Shin , Kunitomi Akira , Katsumata Yoshinori , Nishiyama Takahiko , Nishiyama Nobuhiro , Aizawa Yoshiyasu , Fukuda Keiichi 
Published: October 2017

Background: The monitoring of the effects of direct oral anticoagulants may be beneficial during emergencies and adverse events. We aimed to explore direct oral anticoagulant monitoring in “real-world” settings, in which monitoring methods are limited and loading time can be estimated based on only patient reports. Methods: In 164 patients, plasma anti-Xa activity was assessed using a STA®-Liquid Anti-Xa reagent (Diagnostica Stago, Asnieres, France), and prothrombin time was measured using HemosIL® RecombiPlasTin 2G (Instrumentation Laboratory, Bedford, MA, USA). The loading time was calculated according to the previous dosing time reported by the patient. In the clinic setting, rivaroxaban and apixaban were administered to 103 patients with atrial fibrillation and a blood sample was tested once during a clinic visit. In the hospitalization setting, edoxaban was administered to 61 patients undergoing arthroplasty for prophylaxis of a venous thrombosis and blood samples were tested 3 and 18 h after the last intake. Results: Plasma Xa activity in the clinical setting ranged widely (rivaroxaban: 1.1–424.4 ng/mL, apixaban: 15.4–469.2 ng/mL) during the 11.7 ± 7.0 h following the previous dose. The values varied over a wide range (up to a factor of 2) at the same loading time, especially around the peak period. The plasma anti-Xa activity of rivaroxaban and apixaban showed linear correlations with prothrombin time (R2 = 0.828 and 0.717, respectively). Edoxaban administration prolonged the prothrombin time by only 1.6 ± 1.1 s from the trough to the peak, to a degree that was negatively correlated with age, but not with plasma creatinine level, creatinine clearance, or body mass index. Conclusion: In real-world settings, plasma anti-Xa monitoring should be interpreted considering the wide variations in data, reflecting the variability in patient-reported loading time and interpatient variability.
The reliability and minimal detectable change of the cardiovascular response and self-selected exercise intensity during forward and backward treadmill exercise in individuals with Parkinson disease
Authors: Nelson Reid , Petersen Cheryl 
Published: October 2017

Objective: This study examined test–retest relative (intraclass correlation coefficient) and absolute (minimum detectable change) reliabilities for heart rate, blood pressure, rate of perceived exertion, and the cerebral oxygen response during both forward and backward treadmill walking in clients with Parkinson disease. In addition, the intensity of exercise based on the individual’s heart rate response during forward and backward walking treadmill work was assessed. Design: Test–retest reliability study. Subjects: A total of 22 clients with Parkinson disease (Hoehn and Yahr stages 1–3). Main measures: Outcome measures of heart rate, blood pressure, and cerebral oxygen response were assessed during forward and backward walking on a treadmill for a total of 20 minutes up to an intensity based on the clients’ prior treadmill work and their rate of perceived exertion. Results: Good to excellent 6–8 day test–retest findings for both forward (intraclass correlation coefficient(2,1), 0.89–0.99) and backward (intraclass correlation coefficient(2,1), 0.82–0.99) treadmill walking were found for heart rate, blood pressure, cerebral oxygen response, and the participants’ rate of perceived exertion. Low minimum detectable change (MDC)95 values were found for heart rate (4.9 and 4.8), rate of perceived exertion (1.0 and 1.6), and cerebral oxygen response (1.2 and 0.92), during forward and backward walking, respectively. All treadmill exercise heart rates attained by participants were within an intensity of 54%–87% of the client’s predicted maximal heart rate. Conclusion: Treadmill exercise training can be included in Parkinson disease exercise programs with relative confidence in test–retest reliability of cardiovascular response. It was also demonstrated that individuals with Parkinson disease previously involved with exercise consistently self-select walking speeds which induce heart rates within recommended guidelines for positive cardiovascular adaptation.
Safety of intravenous tobramycin in combination with a variety of anti-pseudomonal antibiotics in children with cystic fibrosis
Authors: Deschamp Ashley R , Pettit Rebecca S , Donaldson Jennifer A , Slaven James E , Davis Stephanie D 
Published: October 2017

Objectives: Previous studies have examined renal safety of once daily intravenous tobramycin in individuals with cystic fibrosis. This has been mainly in combination with ceftazidime in an adolescent or adult population. In this report, we describe our institutional experience of once daily intravenous tobramycin in combination with a variety of second anti-pseudomonal antibiotics in children with cystic fibrosis. Methods: We present a retrospective review including children with cystic fibrosis, who were admitted for a pulmonary exacerbation from January 2009 to December 2011, and treated using intravenous tobramycin. A literature review of once daily intravenous aminoglycoside dosing in cystic fibrosis was performed to compare our results to existing literature. Results: A total of 35 subjects were divided into once daily dosing (n = 20) versus multiple daily dosing (n = 15) groups. Mean age was 11.3 years (± 5.7) for the once daily dosing group and 13.1 years (± 4.4) for the multiple daily dosing group (p = 0.34). All subjects had normal baseline serum creatinine at admission (once daily dosing 0.49 ± 0.14 mg/dL vs multiple daily dosing 0.62 ± 0.23 mg/dL, p = 0.07). All subjects received intravenous tobramycin, and most received piperacillin-tazobactam as their second anti-pseudomonal antibiotic (once daily dosing 45% and multiple daily dosing 40%). There was no significant change in serum creatinine in either group during antibiotic treatment (once daily dosing 0.08 ± 0.12 mg/dL vs. multiple daily dosing 0.06 ± 0.10 mg/dL, p = 0.43). All subjects had significant improvement in lung function following intravenous antibiotic therapy. Conclusion: We show that both once daily dosing and multiple daily dosing of intravenous tobramycin in combination with a variety of second anti-pseudomonal antibiotics were safe in terms of nephrotoxicity in children with cystic fibrosis. These findings are important given existing literature mainly examines once daily tobramycin in combination with ceftazidime, a cephalosporin, and the majority of our patients were on tobramycin with piperacillin-tazobactam, an extended spectrum penicillin plus beta-lactam. This contributes new information not previously examined in a pediatric cystic fibrosis population.
Racial and Ethnic Disparities in Cancer Survival: The Contribution of Tumor, Sociodemographic, Institutional, and Neighborhood Characteristics
Authors: Ellis Libby , Canchola Alison J. , Spiegel David , Ladabaum Uri , Haile Robert , Gomez Scarlett Lin 
Published: October 2017

Purpose Racial/ethnic disparities in cancer survival in the United States are well documented, but the underlying causes are not well understood. We quantified the contribution of tumor, treatment, hospital, sociodemographic, and neighborhood factors to racial/ethnic survival disparities in California. Materials and Methods California Cancer Registry data were used to estimate population-based cancer-specific survival for patients diagnosed with breast, prostate, colorectal, or lung cancer between 2000 and 2013 for each racial/ethnic group (non-Hispanic black, Hispanic, Asian American and Pacific Islander, and separately each for Chinese, Japanese, and Filipino) compared with non-Hispanic whites. The percentage contribution of factors to overall racial/ethnic survival disparities was estimated from a sequence of multivariable Cox proportional hazards models. Results In baseline models, black patients had the lowest survival for all cancer sites, and Asian American and Pacific Islander patients had the highest, compared with whites. Mediation analyses suggested that stage at diagnosis had the greatest influence on overall racial/ethnic survival disparities accounting for 24% of disparities in breast cancer, 24% in prostate cancer, and 16% to 30% in colorectal cancer. Neighborhood socioeconomic status was an important factor in all cancers, but only for black and Hispanic patients. The influence of marital status on racial/ethnic disparities was stronger in men than in women. Adjustment for all covariables explained approximately half of the overall survival disparities in breast, prostate, and colorectal cancer, but it explained only 15% to 40% of disparities in lung cancer. Conclusion Overall reductions in racial/ethnic survival disparities were driven largely by reductions for black compared with white patients. Stage at diagnosis had the largest effect on racial/ethnic survival disparities, but earlier detection would not entirely eliminate them. The influences of neighborhood socioeconomic status and marital status suggest that social determinants, support mechanisms, and access to health care are important contributing factors.
Impact of Intensity-Modulated Radiotherapy on Health Care Costs of Patients With Anal Squamous Cell Carcinoma
Authors: Chin Alexander L. , Pollom Erqi L. , Qian Yushen , Koong Albert C. , Chang Daniel T. 
Published: October 2017

Purpose: Drivers of variation in the cost of care after chemoradiotherapy for the management of anal squamous cell carcinoma (SCC) have not been fully elucidated. We sought to characterize the direct and indirect impact of radiotherapy modality on health care costs among patients with anal SCC. Patients and Methods: A retrospective cohort study was performed using the 2014 linkage of the SEER-Medicare database. We identified 1,025 patients with anal SCC diagnosed between 2001 and 2011 and treated with chemoradiotherapy. Propensity score matching was used to balance baseline differences between patients treated with intensity-modulated radiotherapy (IMRT) and those treated with three-dimensional conformal radiotherapy (3D-CRT). Differences in total, cancer-attributable, and procedure-specific costs between groups were measured. Results: Radiation-related, patient out-of-pocket, and total costs in the 1-year period after radiotherapy start were all higher for the IMRT group than the 3D-CRT group (median total cost, $35,890 v $27,262, respectively; P < .001). Patients who received IMRT had lower cumulative costs associated with urgent hospitalizations and emergency department visits at both 9 months and 1 year after treatment start compared with a matched cohort of patients who received 3D-CRT (median, $711 v $4,957 at 1 year, respectively; P = .021). Conclusion: Although total costs of care were higher for IMRT compared with 3D-CRT, primarily as a result of higher radiotherapy-specific costs, IMRT was associated with decreased unplanned health care utilization costs starting at 9 months after treatment start. Radiotherapy-centered episodes of care may need to encompass a longer time horizon to capture the full cost savings associated with more advanced radiation modalities.