bluuebunny/crossref_metadata_2025_split huggingface dataset:
ABOVEGROUND BIOMASS AND CARBON STOCK ESTIMATION USING DOUBLE SAMPLING APPROACH AND REMOTELY-SENSED DATA
Authors: Mohd Zaki Nurul Ain , Abd Latif Zulkiflee , Zainal Mohd Zainee 
Published: May 2016

Tropical forest embraces a large stock of carbon and contributes to the enormous amount of aboveground biomass (AGB) in the global carbon cycle. In order to quantify the carbon inventory, field data is vital for accurately determining the forest parameter such as diameter at the breast height (DBH), height of the tree (h) ,crown diameter (CD) and tree species. The merging of the multi-sensory remote sensing which is LiDAR (Light Detection and Ranging) and very high resolution satellite imagery can reduce the labor intensive of field sampling for a large area of carbon inventory data. Double sampling approach which is combination of the field sampling plot measurement with ancillary remote sensing data used to improve the precision of AGB estimation compared by using field data alone. Hence, this study aims: (1) to describe the use of field data plots in a statistical way, and (2) to determine the potential of LiDAR data in a double sampling forest aboveground biomass and carbon stock inventories and (3) to compare the used of field data plot itself or combination with LiDAR data to quantify the aboveground biomass and carbon stock for upcoming inventories.
CORROSION PROCESSES ON WEATHERING STEEL RAILWAY BRIDGE IN PRAGUE
Authors: Urban Viktor , Krivy Vit , Buchta Vojtech 
Published: May 2016

This contribution deals with experimental corrosion tests carried out on the weathering steel railway bridge in Prague. The basic specific property of the weathering steel is an ability to create in favourable environment a protective patina layer on its surface. Since 1968 weathering steel is used under the name “Atmofix” in the Czech Republic and can be used as a standard structural material without any corrosion protection. The weathering steel Atmofix is mostly used for bridge structures and lattice transmission towers. Some of these constructions built in the Czech Republic have been assessed and inspected in the last few years. Authors of this paper developed a new methodology of non-destructive experimental testing of corrosion processes. Testing specimens are installed on typical surfaces of steel bridges in such a way to simulate real conditions of the examined surface. This paper describes results of corrosion tests (thickness of corrosion products, corrosion losses and X-Ray analysis) after one-year exposure, correlation factor and dependence of location.
A novel approach to assess pulmonary function in patients with chronic obstructive pulmonary disease using tissue velocity imaging.
Authors: Zheng Xiao-Zhi , Wu Jing , Tan Xu-Yan 
Published: May 2016

Aims: To explore the feasibility of quantitative evaluation of pulmonary function in patients with chronic obstructive pulmonary disease (COPD) using tissue velocity imaging (TVI) and strain rate imaging (SRI) via transthoracic lung ultrasonography. Material and methods: Eighty inpatients with clinically diagnosed COPD underwent pulmonary function test and transthoracic lung ultrasound on the same day. Lung ultrasound variables and pulmonary function parameters were analyzed. Results: All patients with COPD had faster breathing and significant reduced lung function compared with healthy participants (p<0.05). The lung ultrasound parameters, velocity (max-min, cm/s), displacement (max-min, mm), strain (max-min, %) and strain rate (max-min, 1/s) were significantly higher in patients with COPD (p<0.05). A good negative correlation was found between lung ultrasound variables and pulmonary function parameters in patients with COPD. Stepwise multiple regression analysis indicated that the velocity (max-min, cm/s) was the only independent determinant of FEV1/FVC (%). With the use of FEV1/FVC<70% as the criteria of irreversible pulmonary function impairment to distinguish an abnormal pulmonary function, the area under the ROC was 0.99 for the velocity (max-min, cm/s) of the lung tissue in the process of breathing. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of the cut off value (1.19 cm/s) was 97.63%, 100%, 100%, 80%, and 98%, respectively (p<0.001). Conclusions: Tissue velocity imaging via transthoracic lung ultrasound is a useful modality in the assessment of pulmonary function in patients with COPD.
A Monte Carlo study on 223Ra imaging for unsealed radionuclide therapy
Authors: Takahashi Akihiko , Miwa Kenta , Sasaki Masayuki , Baba Shingo 
Published: May 2016

Purpose:Radium‐223 (223Ra), an α‐emitting radionuclide, is used in unsealed radionuclide therapy for metastatic bone tumors. The demand for qualitative 223Ra imaging is growing to optimize dosimetry. The authors simulated 223Ra imaging using an in‐house Monte Carlo simulation code and investigated the feasibility and utility of 223Ra imaging.Methods:The Monte Carlo code comprises two modules, hexagon and nai. The hexagon code simulates the photon and electron interactions in the tissues and collimator, and the nai code simulates the response of the NaI detector system. A 3D numeric phantom created using computed tomography images of a chest phantom was installed in the hexagon code. 223Ra accumulated in a part of the spine, and three x‐rays and 19 γ rays between 80 and 450 keV were selected as the emitted photons. To evaluate the quality of the 223Ra imaging, the authors also simulated technetium‐99m (99mTc) imaging under the same conditions and compared the results.Results:The sensitivities of the three photopeaks were 147 counts per unit of source activity (cps MBq−1; photopeak: 84 keV, full width of energy window: 20%), 166 cps MBq−1 (154 keV, 15%), and 158 cps MBq−1 (270 keV, 10%) for a low‐energy general‐purpose (LEGP) collimator, and those for the medium‐energy general‐purpose (MEGP) collimator were 33, 13, and 8.0 cps MBq−1, respectively. In the case of 99mTc, the sensitivity was 55 cps MBq−1 (141 keV, 20%) for LEGP and 52 cps MBq−1 for MEGP. The fractions of unscattered photons of the total photons reflecting the image quality were 0.09 (84 keV), 0.03 (154 keV), and 0.02 (270 keV) for the LEGP collimator and 0.41, 0.25, and 0.50 for the MEGP collimator, respectively. Conversely, this fraction was approximately 0.65 for the simulated 99mTc imaging. The sensitivity with the LEGP collimator appeared very high. However, almost all of the counts were because of photons that penetrated or were scattered in the collimator; therefore, the proportions of unscattered photons were small.Conclusions:Their simulation study revealed that the most promising scheme for 223Ra imaging is an 84‐keV window using an MEGP collimator. The sensitivity of the photopeaks above 100 keV is too low for 223Ra imaging. A comparison of the fractions of unscattered photons reveals that the sensitivity and image quality are approximately two‐thirds of those for 99mTc imaging.
Minimizing treatment planning errors in proton therapy using failure mode and effects analysis
Authors: Zheng Yuanshui , Johnson Randall , Larson Gary 
Published: May 2016

Purpose:Failure mode and effects analysis (FMEA) is a widely used tool to evaluate safety or reliability in conventional photon radiation therapy. However, reports about FMEA application in proton therapy are scarce. The purpose of this study is to apply FMEA in safety improvement of proton treatment planning at their center.Methods:The authors performed an FMEA analysis of their proton therapy treatment planning process using uniform scanning proton beams. The authors identified possible failure modes in various planning processes, including image fusion, contouring, beam arrangement, dose calculation, plan export, documents, billing, and so on. For each error, the authors estimated the frequency of occurrence, the likelihood of being undetected, and the severity of the error if it went undetected and calculated the risk priority number (RPN). The FMEA results were used to design their quality management program. In addition, the authors created a database to track the identified dosimetric errors. Periodically, the authors reevaluated the risk of errors by reviewing the internal error database and improved their quality assurance program as needed.Results:In total, the authors identified over 36 possible treatment planning related failure modes and estimated the associated occurrence, detectability, and severity to calculate the overall risk priority number. Based on the FMEA, the authors implemented various safety improvement procedures into their practice, such as education, peer review, and automatic check tools. The ongoing error tracking database provided realistic data on the frequency of occurrence with which to reevaluate the RPNs for various failure modes.Conclusions:The FMEA technique provides a systematic method for identifying and evaluating potential errors in proton treatment planning before they result in an error in patient dose delivery. The application of FMEA framework and the implementation of an ongoing error tracking system at their clinic have proven to be useful in error reduction in proton treatment planning, thus improving the effectiveness and safety of proton therapy.
In Vivo
Rectal Mucosal Barrier Function Imaging in a Large-Animal Model by Using Confocal Endomicroscopy: Implications for Injury Assessment and Use in HIV Prevention Studies
Authors: Vargas Gracie , Vincent Kathleen Listiak , Zhu Yong , Szafron David , Brown Tyra Caitlin , Villarreal Paula Patricia , Bourne Nigel , Milligan Gregg N. , Motamedi Massoud 
Published: May 2016

ABSTRACT

Injury occurring on the surface of the rectal mucosal lining that causes defects in barrier function may result in increased risk for transmission of infection by HIV and other pathogens. Such injury could occur from microbicidal or other topical agents, mechanical trauma during consensual or nonconsensual intercourse, or inflammatory conditions. Tools for evaluation of rectal mucosal barrier function for assessing the mucosa under these conditions are lacking, particularly those that can provide
in vivo
structural and functional barrier integrity assessment and are adaptable to longitudinal imaging. We investigated confocal endomicroscopy (CE) as a means for
in vivo
imaging of the rectal epithelial barrier in the ovine model following spatially confined injury to the surface at a controlled site using a topical application of the microbicide test agent benzalkonium chloride. Topical and intravenous (i.v.) fluorescent probes were used with CE to provide subcellular resolution imaging of the mucosal surface and assessment of barrier function loss. A 3-point CE grading system based on cellular structure integrity and leakage of dye through the mucosa showed significant differences in score between untreated (1.19 ± 0.53) and treated (2.55 ± 0.75) tissue (
P
< 0.0001). Histological grading confirmed findings of barrier compromise. The results indicate that CE is an effective means for detecting epithelial injury and barrier loss following localized trauma in a large-animal model. CE is promising for real-time rectal mucosal evaluation after injury or trauma or topical application of emerging biomedical prevention strategies designed to combat HIV.
Prospective Study of Plasmodium vivax Malaria Recurrence after Radical Treatment with a Chloroquine-Primaquine Standard Regimen in Turbo, Colombia
Authors: Zuluaga-Idárraga Lina , Blair Silvia , Akinyi Okoth Sheila , Udhayakumar Venkatachalam , Marcet Paula L. , Escalante Ananias A. , Alexander Neal , Rojas Carlos 
Published: May 2016

ABSTRACT

Plasmodium vivax
recurrences help maintain malaria transmission. They are caused by recrudescence, reinfection, or relapse, which are not easily differentiated. A longitudinal observational study took place in Turbo municipality, Colombia. Participants with uncomplicated
P. vivax
infection received supervised treatment concomitantly with 25 mg/kg chloroquine and 0.25 mg/kg/day primaquine for 14 days. Incidence of recurrence was assessed over 180 days. Samples were genotyped, and origins of recurrences were established. A total of 134 participants were enrolled between February 2012 and July 2013, and 87 were followed for 180 days, during which 29 recurrences were detected. The cumulative incidence of first recurrence was 24.1% (21/87) (95% confidence interval [CI], 14.6 to 33.7%), and 86% (18/21) of these events occurred between days 51 and 110. High genetic diversity of
P. vivax
strains was found, and 12.5% (16/128) of the infections were polyclonal. Among detected recurrences, 93.1% (27/29) of strains were genotyped as genetically identical to the strain from the previous infection episode, and 65.5% (19/29) of infections were classified as relapses. Our results indicate that there is a high incidence of
P. vivax
malaria recurrence after treatment in Turbo municipality, Colombia, and that a large majority of these episodes are likely relapses from the previous infection. We attribute this to the primaquine regimen currently used in Colombia, which may be insufficient to eliminate hypnozoites.
Discovery of a Broad-Spectrum Antiviral Compound That Inhibits Pyrimidine Biosynthesis and Establishes a Type 1 Interferon-Independent Antiviral State
Authors: Chung Dong-Hoon , Golden Jennifer E. , Adcock Robert S. , Schroeder Chad E. , Chu Yong-Kyu , Sotsky Julie B. , Cramer Daniel E. , Chilton Paula M. , Song Chisu , Anantpadma Manu , Davey Robert A. , Prodhan Aminul I. , Yin Xinmin , Zhang Xiang 
Published: May 2016

ABSTRACT
Viral emergence and reemergence underscore the importance of developing efficacious, broad-spectrum antivirals. Here, we report the discovery of tetrahydrobenzothiazole-based compound 1, a novel, broad-spectrum antiviral lead that was optimized from a hit compound derived from a cytopathic effect (CPE)-based antiviral screen using Venezuelan equine encephalitis virus. Compound 1 showed antiviral activity against a broad range of RNA viruses, including alphaviruses, flaviviruses, influenza virus, and ebolavirus. Mechanism-of-action studies with metabolomics and molecular approaches revealed that the compound inhibits host pyrimidine synthesis and establishes an antiviral state by inducing a variety of interferon-stimulated genes (ISGs). Notably, the induction of the ISGs by compound 1 was independent of the production of type 1 interferons. The antiviral activity of compound 1 was cell type dependent with a robust effect observed in human cell lines and no observed antiviral effect in mouse cell lines. Herein, we disclose tetrahydrobenzothiazole compound 1 as a novel lead for the development of a broad-spectrum, antiviral therapeutic and as a molecular probe to study the mechanism of the induction of ISGs that are independent of type 1 interferons.
Pharmacokinetics of Vancomycin in Elderly Patients Aged over 80 Years
Authors: Bourguignon Laurent , Cazaubon Yoann , Debeurme Guillaume , Loue Constance , Ducher Michel , Goutelle Sylvain 
Published: May 2016

ABSTRACT

Since the 1950s, vancomycin has remained a reference treatment for severe infections caused by Gram-positive bacteria, including methicillin-resistant
Staphylococcus aureus
. Vancomycin is a nephrotoxic and ototoxic drug mainly eliminated through the kidneys. It has a large interindividual pharmacokinetic variability, which justifies monitoring its plasma concentrations in patients. This is especially important in patients aged over 80 years, who frequently have renal impairment. However, the pharmacokinetics of vancomycin in this population is very poorly described in the literature. The objective of this work was to propose a model able to predict the pharmacokinetics of vancomycin in very elderly people. First, a population pharmacokinetic model was carried out using the algorithm NPAG (nonparametric adaptive grid) on a database of 70 hospitalized patients aged over 80 years and treated with vancomycin. An external validation then was performed on 41 patients, and the predictive capabilities of the model were assessed. The model had two compartments and six parameters. Body weight and creatinine clearance significantly influenced vancomycin volume of distribution and body clearance, respectively. The means (± standard deviations) of vancomycin volume of distribution and clearance were 36.3 ± 15.2 liter and 2.0 ± 0.9 liter/h, respectively. In the validation group, the bias and precision were −0.75 mg/liter and 8.76 mg/liter for population predictions and −0.39 mg/liter and 2.68 mg/liter for individual predictions. In conclusion, a pharmacokinetic model of vancomycin in a very elderly population has been created and validated for predicting plasma concentrations of vancomycin.
Isolation and Characterization of Escherichia coli Sequence Type 131 and Other Antimicrobial-Resistant Gram-Negative Bacilli from Clinical Stool Samples from Veterans
Authors: Mohamed Muhanad , Clabots Connie , Porter Stephen B. , Thuras Paul , Johnson James R. 
Published: May 2016

ABSTRACT

Emerging multidrug-resistant (MDR) Gram-negative bacilli (GNB), including
Escherichia coli
sequence type 131 (ST131) and its resistance-associated
H
30 subclone, constitute an ever-growing public health threat. Their reservoirs and transmission pathways are incompletely defined. To assess diarrheal stools as a potential reservoir for ST131-
H
30 and other MDR GNB, we cultured 100 clinical stool samples from a Veterans Affairs Medical Center clinical laboratory (October to December 2011) for fluoroquinolone- and extended-spectrum cephalosporin (ESC)-resistant
E. coli
and other GNB, plus total
E. coli
. We then characterized selected resistant and susceptible
E. coli
isolates by clonal group, phylogenetic group, virulence genotype, and pulsotype and screened all isolates for antimicrobial resistance. Overall, 79 of 100 stool samples yielded GNB (52
E. coli
; 48 other GNB). Fifteen samples yielded fluoroquinolone-resistant
E. coli
(10 were ST131, of which 9 were
H
30), 6 yielded ESC-resistant
E. coli
(2 were ST131, both non-
H
30), and 31 yielded susceptible
E. coli
(1 was ST131, non-
H
30), for 13 total ST131-positive samples. Fourteen non-
E. coli
GNB were ESC resistant, and three were fluoroquinolone resistant. Regardless of species, almost half (46%) of the fluoroquinolone-resistant and/or ESC-resistant non-
E. coli
GNB were resistant to at least three drug classes. Fecal ST131 isolates closely resembled reference clinical ST131 isolates according to virulence genotypes and pulsed-field gel electrophoresis (PFGE) profiles. Thus, a substantial minority (30%) of veterans with diarrhea who undergo stool testing excrete antibiotic-resistant GNB, including
E. coli
ST131. Consequently, diarrhea may pose transmission risks for more than just diarrheal pathogens and may help disseminate clinically relevant ST131 strains and other MDR GNB within hospitals and the community.
Isavuconazole Population Pharmacokinetic Analysis Using Nonparametric Estimation in Patients with Invasive Fungal Disease (Results from the VITAL Study)
Authors: Kovanda Laura L. , Desai Amit V. , Lu Qiaoyang , Townsend Robert W. , Akhtar Shahzad , Bonate Peter , Hope William W. 
Published: May 2016

ABSTRACT

Isavuconazonium sulfate (Cresemba; Astellas Pharma Inc.), a water-soluble prodrug of the triazole antifungal agent isavuconazole, is available for the treatment of invasive aspergillosis (IA) and invasive mucormycosis. A population pharmacokinetic (PPK) model was constructed using nonparametric estimation to compare the pharmacokinetic (PK) behaviors of isavuconazole in patients treated in the phase 3 VITAL open-label clinical trial, which evaluated the efficacy and safety of the drug for treatment of renally impaired IA patients and patients with invasive fungal disease (IFD) caused by emerging molds, yeasts, and dimorphic fungi. Covariates examined were body mass index (BMI), weight, race, impact of estimated glomerular filtration rate (eGFR) on clearance (CL), and impact of weight on volume. PK parameters were compared based on IFD type and other patient characteristics. Simulations were performed to describe the MICs covered by the clinical dosing regimen. Concentrations (
n
= 458) from 136 patients were used to construct a 2-compartment model (first-order absorption compartment and central compartment). Weight-related covariates affected clearance, but eGFR did not. PK parameters and intersubject variability of CL were similar across different IFD groups and populations. Target attainment analyses demonstrated that the clinical dosing regimen would be sufficient for total drug area under the concentration-time curve (AUC)/MIC targets ranging from 50.5 for
Aspergillus
spp. (up to the CLSI MIC of 0.5 mg/liter) to 270 and 5,053 for
Candida albicans
(up to MICs of 0.125 and 0.004 mg/liter, respectively) and 312 for non-
albicans Candida
spp. (up to a MIC of 0.125 mg/liter). The estimations for
Candida
spp. were exploratory considering that no patients with
Candida
infections were included in the current analyses. (The VITAL trial is registered at ClinicalTrials.gov under number NCT00634049.)
Effect of Obesity on the Population Pharmacokinetics of Meropenem in Critically Ill Patients
Authors: Alobaid Abdulaziz S. , Wallis Steven C. , Jarrett Paul , Starr Therese , Stuart Janine , Lassig-Smith Melissa , Ordóñez Mejia Jenny Lisette , Roberts Michael S. , Lipman Jeffrey , Roberts Jason A. 
Published: May 2016

ABSTRACTSevere pathophysiological changes in critical illness can lead to dramatically altered antimicrobial pharmacokinetics (PK). The additional effect of obesity on PK potentially increases the challenge for effective dosing. The aim of this prospective study was to describe the population PK of meropenem for a cohort of critically ill patients, including obese and morbidly obese patients. Critically ill patients prescribed meropenem were recruited into the following three body mass index (BMI) groups: nonobese (18.5 to 29.9 kg/m2), obese (30.0 to 39.9 kg/m2), and morbidly obese (≥40 kg/m2). Serial plasma samples were taken, and meropenem concentrations were determined using a validated chromatographic method. Population PK analysis and Monte Carlo dosing simulations were undertaken with Pmetrics. Nineteen critically ill patients with different BMI categories were enrolled. The patients' mean ± standard deviation (SD) age, weight, and BMI were 49 ± 15.9 years, 95 ± 22.0 kg, and 33 ± 7.0 kg/m2, respectively. A two-compartment model described the data adequately. The mean ± SD parameter estimates for the final covariate model were as follows: clearance (CL), 15.5 ± 6.0 liters/h; volume of distribution in the central compartment (V1), 11.7 ± 5.8 liters; intercompartmental clearance from the central compartment to the peripheral compartment, 25.6 ± 35.1 liters h−1; and intercompartmental clearance from the peripheral compartment to the central compartment, 8.32 ± 12.24 liters h−1. Higher creatinine clearance (CLCR) was associated with a lower probability of target attainment, with BMI having little effect. Although obesity was found to be associated with an increasedV1, dose adjustment based on CLCRappears to be more important than patient BMI.