bluuebunny/crossref_metadata_2025_split huggingface dataset:
To Integrate or…? Agricultural Development in Sierra Leone
Authors: Airey A. , Binns J. A. , Mitchell P. K. 
Published: August 2010

SUMMARY Semi‐subsistence peasant farming in the forest regions of Sierra Leone does not lend itself to ready understanding by western‐trained fieldworkers. But that understanding is essential if development objectives and procedures are to be successful. Some progress has been achieved through the application of systems‐based modes of analysis of detailed empirical material. Although growth in the agricultural sector has long been part of government policies, achievement has fallen short – partly at least through errors in basic philosophy. The Integrated Agricultural Development Project Eastern Area (IADPEA) may prove to be a more realistic and successful vehicle for developing, rather than replacing, traditional farm production.RÉSUMÉ Intégrer ou …? Le développement agricole de la Sierra LeoneL'agriculture de semi‐subsistance des régions forestières de la Sierra Leone ne se prête pas facilement à l'interprétation pour des enquêteurs formés dans les pays occidentaux. Mais il est indispensable de la comprendre pour assurer le succès des procédures et objectifs de développement. Certains progrès ont pu être accomplis grâce au recours à la systématisation des modes d'analyse des données empiriques détaillés. Bien que la croissance du secteur agricole fasse depuis longtemps partie des buts du gouvernement, les résultats laissent à désirer, en partie du moins à cause d'erreurs d'orientation fondamentales. Le Projet de développement agricole intégré de la zone est (IADPEA) pourrait devenir un instrument plus réaliste, et ayant plus de chances de succès, pour développer, plutôt que pour remplacer la production agricole traditionnelle.RESUMEN ¿ Integrar o …? Desarrollo agrícola en Sierra LeonaLas condiciones campesinas de semisubsistencia en las regiones forestales de Sierra Leona no se prestan a una fácil comprensión por parte de los expertos agrícolas entrenados en Occidente. No obstante, este entendimiento es esencial si han de llevarse a cabo de manera fructífera los objetivos y procedimientos del desarrollo. Se ha logrado cierto progreso mediante la aplicación de los análisis de materiales empíricos detallados basados en sistemas. Aunque el crecimiento en el sector agrícola ha formado parte desde hace mucho tiempo de las políticas gubernamentales, los logros han sido escasos – en parte a causa de los errores que se cometieron en la filosofía empleada. El proyecto de desarrollo agrícola integrado para la zona oriental puede que sea un vehículo para el desarrollo con bases más realistas y mayores posibilidades de triunfar, en lugar de reemplazar los sistemas tradicionales de producción agrícola.
Hierarchical Modeling of Heat Transfer in Silicon-Based Electronic Devices
Authors: Goicochea Javier V. , Madrid Marcela , Amon Cristina 
Published: August 2010

AbstractA hierarchical model of heat transfer for the thermal analysis of electronic devices is presented. The integration of participating scales (from nanoscale to macroscales) is achieved by (i) estimating the input parameters and thermal properties to solve the Boltzmann transport equation (BTE) for phonons using molecular dynamics (MD), including phonon relaxation times, dispersion relations, group velocities, and specific heat, (ii) applying quantum corrections to the MD results to make them suitable for the solution of BTE, and (iii) numerically solving the BTE in space and time subject to different boundary and initial conditions. We apply our hierarchical model to estimate the silicon out-of-plane thermal conductivity and the thermal response of an silicon on insulator (SOI) device subject to Joule heating. We have found that relative phonon contribution to the overall conductivity changes as the dimension of the domain is reduced as a result of phonon confinement. The observed reduction in the thermal conductivity is produced by the progressive transition of modes in the diffusive regime (as in the bulk) to transitional and ballistic regimes as the film thickness is decreased. In addition, we have found that relaxation time expressions for optical phonons are important to describe the transient response of SOI devices and that the characteristic transport regimes, determined with Holland and Klemens phonon models, differ significantly.
TU‐D‐BRA‐01: Treating a Moving Target under the Guidance of Hybrid kV and MV Imaging
Authors: Wiersma R 
Published: August 2010

In recent years, MV and kV electronic flat panel imaging devices have become commonplace equipment installed on the gantry of many newer medical LINACs. Such imaging devices are now routinely used in the clinic for verification of correct initial patient setup before start of a treatment fraction. This is done through MV portal images, 2D kV fluoroscopic images, or cone‐beam CT. However, these amorphous‐silicon detectors have not been used to their full potential. With high resolution imaging capture rates of ∼ 10 frames per second, the role of these MV and kV detectors can be additionally expanded to include real‐time target tracking during the actual radiation treatment delivery process.This lecture will provide an overview of recent research in the use of MV and kV imagers for real‐time tracking purposes. In addition, an explanation of the basic theory and methods necessary to perform real‐time tracking will be discussed.Learning Objectives:1. Fundamentals of MV and kV flat panel detectors.2. Image processing and prediction methods used for real‐time MV and kV intheclinic.3. Issues involved in implementing hybrid MV and kV in the clinic.
WE‐A‐204B‐01: Possible Causes for the Reduced Efficacy of US Based Image Guided Treatment of Prostate Cancer with External Beam Radiation Therapy
Authors: Van den Heuvel F 
Published: August 2010

Ultrasound systems have been in use to provide image guided radiation therapy for more than a decade. They have been instrumental in changing the treatment paradigm in which it became accepted to take a longer time to visualize the internal organs in order to facilitate more precise treatments. Indeed the first results led to the generation of on‐line correction protocols and the notion that it was possible to treat tumors using smaller margins. Prostate treatments were the most popular to be used with this approach, although other organs could be targeted too.After its introduction questions arose regarding the reliability of this approach. A number of groups reported discrepancies independently of each other as well as providing different explanations. Unfortunately, a consensus as to why exactly these problems occur is lacking.This paper investigates the causes for the variations observed by:1. Revisiting the original data and conclusions,2. Re‐interpret the data in view of the current state of knowledge regarding intra‐fractional motion,3. Observe how the current updates in technology affect the efficacy, and4. Introduce newer developments in ultrasound technology pertaining to its use in radiation oncology.It is the goal of this presentation to elucidate a number of techniques used in the analysis:1. How to compare sets of positioning data and perform robust statistical data‐analysis2. Interpret organ motion to yield margin sizes to compensate for setup and patient motion3. Learn about the main modes of motion of different organs during treatments4. Learn the different parameters affecting the measurement using ultrasound to perform absolute positioning5. Learn about comparing images stemming from different modalities.
WE‐A‐204B‐03: Image Guidance of Focused Ultrasound
Authors: Pauly K Butts 
Published: August 2010

Ultrasound can be focused to interact with tissues and deliver drugs deep within the body, without damage to overlying tissues. Image guidance is important for targeting therapy, ensuring treatment and safety, and for assessing therapy. Ultrasound imaging, magnetic resonance imaging, optical imaging, and PET are all being developed and evaluated for these tasks. This presentation will describe some current research areas in the image guidance of focused ultrasound.For tissue ablation, it is critically important to monitor tissue temperature. This is possible with both ultrasound imaging and MRI. A current research area concerns thermal ablations of moving organs, such as the liver and kidneys. We have developed a method for FUS ablation of abdominal organs including real‐time MR thermometry, organ and transducer tracking, and beam steering.There are a number of methods under investigation for the visualization of ablated tissue. Both ultrasound‐based and MR‐based acoustic radiation force imaging (ARFI) methods are potential candidates. ARFI relies on tissue displacement by the ultrasound beam, which is related to the tissue stiffness. Evaluating the change in tissue stiffness provides the spatial extent of the thermal ablation. Other evaluative imaging includes contrast enhanced MRI, which visualizes disruption of perfusion, and diffusion‐weighted MRI, which demonstrates a 30% decrease in ADC in the ablated tissue.The displacement visualized with ARFI is also proportional to the ultrasound intensity. Therefore, visualization of the focal spot can be done without a significant temperature rise. In the MR‐guided neurosurgical applications of focused ultrasound, this could allow the focal spot to be visualized more safely than with a small temperature rise required for MR thermometry visualization. In addition, it provides a means for image feedback when correcting phase aberrations from the skull.For drug delivery, image monitoring of delivery is being developed with MRI, PET, and optical imaging. Blood‐brain barrier opening can be detected with uptake of a gadolinium contrast agent on MR‐images. Investigators at UC Davis have shown that the drug shell can be visualized with PET, while the contents are visualized with optical imaging, to enable visualization of the drug release.Learning Objectives:1. Understand the basis for acoustic radiation force imaging and its applications2. Understand the current research in the image guidance of focused ultrasound
WE‐D‐BRA‐01: Stereotactic Body Radiotherapy (SBRT): Technical and Clinical Considerations
Authors: Kavanagh B , Chetty IJ , Balter JM , Solberg TD 
Published: August 2010

Stereotactic Body Radiotherapy (SBRT) has now been applied clinically for more than a decade. The accumulation of published technical and clinical studies currently available has offered insights into both the efficacy and special concerns associated with the delivery of SBRT to different sites. The safe and effective delivery of SBRT requires careful attention to tumor motion management, special dosimetric and planning challenges, and commissioning of dedicated equipment and quality assurance. This session will provide an overview of these important technical considerations as well as a survey of clinical outcomes reported based on the use of SBRT in the treatment of different tumor sites.Learning Objectives:1. Describe available methods for motion management and the rational selection of planning margins2. Discuss techniques for SBRT treatment planning and the impact of dose calculation algorithm3. Describe key elements of commissioning, patient‐specific QA, and routine periodic machine performance QA4. Review clinical observations reported after SBRT for lung, liver, pancreas, spine, head & neck, and prostate
WE‐D‐204C‐01: Opportunities and Considerations for Multi‐institutional Clinical Trials Research
Authors: Deye J , Ibbott G , Michalski J , Tucker S , Xiao Y , Deasy J 
Published: August 2010

The physicist role in clinical trials is sometimes confined to participation in filling out questionnaires, reviewing treatment plans, performing phantom studies, and verifying export of the correct information to the clinical trial group. However, participation in clinical trials research can be a rewarding and productive endeavor. The focus of this session is to highlight for investigators the potential and rewards of such research.In this session, experts will present on different roles in supporting and conducting clinical trials research and secondary analyses. First, the role of the National Institute of Health in supporting clinical trials research will be described. Then, the richness of the data collected by the Radiological Physics Center (RPC) to support quality in clinical trials since its inception in 1968 will be described. The RPC has provided quality independent audits of delivered dose, design of phantoms, and other clinical trials support. More recently, the Advanced Technology Consortium (ATC) has been collecting digital 3D data to support clinical trials research for prospective and retrospective trials. Considerations with respect to the quality of data needed for retrospective analyses will then be discussed. Finally, individual investigators will share their experiences in 1) conducting research as a member of a clinical trials group and 2) furthering that research as an independent investigator supported by an NIH R‐01 grant.The panel discussion will provide an opportunity for investigators to ask questions about the nuts and bolts of becoming active in clinical trials support ‐ and ultimately in clinical trials research.Learning Objectives:1. NIH mechanisms for funding clinical trials research2. Examples of the RPC's database in support of clinical trials3. Potential opportunities to conduct clinical trials research through the ATC4. Ways to improve the quality of data acquired during clinical trials5. Examples of research in the RTOG utilizing multi‐modality imaging6. Examples of improved biological models utilizing multi‐institutional data
TH‐C‐BRB‐03: On the Suitability of Using NanoDot for Measuring Dose Distributions Resulting from KV‐CBCT Acquisitions
Authors: Ding G , Coffey C 
Published: August 2010

Purpose: There is a growing need to determine radiation exposure and dose distributions resulting from an image‐guidance procedure. Although Monte Carlo simulations are capable to calculate the dose distributions experimental measurements remain the gold standards to validate the accuracy of calculations. This study investigated the suitability of nanoDot dosimeters for measuring accumulative dose at several locations simultaneously to determine 3D dose distributions resulting from a kilovoltage cone‐beam CT (kV‐CBCT) scan. Method and Materials: The nanoDot dosimeters read with a microStar reader by Landauer were used in the study. The system can be calibrated to measure dose from kilovoltage to megavoltage energy beams. The manufacturer provides a set of calibration dosimeters for 80 kVp x‐rays. The accuracy of the nanoDot dosimeters for absorbed dose measurements for kV‐CBCT scans was validated by using an ionization chamber in which the air‐kerma calibration factors were traceable to National Standards Laboratory. The relative dose distributions measured with nanoDot were compared with Monte Carlo calculated dose distributions in a PLASTIC WATER® LR phantom. Results: Seven nanoDot dosimeters were placed at different locations to determine dose distributions resulting from each kV‐CBCT scan protocol. There are five different kV‐CBCT scan protocols in the Varian OBI 1.4 system including Head Low‐dose Thorax Pelvis and Pelvis Spot Light with two different Bow‐tie filters. Both absolute and relative dose distributions were investigated. The dose values measured from 35 points generally agree with that of Monte Carlo calculations within 2–4%. Conclusion: The nanoDot dosimeters have been shown to be very suitable detectors for measuring 3D dose distributions resulting from kV‐CBCT scans due to its small size the ease of use good reproducibility and manageable photon energy dependence.Conflict of Interest: The microStar reader used in the research was provided by Landauer Inc. Glenwood IL
Genetic Determinants Involved in the Susceptibility of
Pseudomonas aeruginosa
to β-Lactam Antibiotics
Authors: Alvarez-Ortega Carolina , Wiegand Irith , Olivares Jorge , Hancock Robert E. W. , Martínez José Luis 
Published: August 2010

ABSTRACT

The resistome of
P. aeruginosa
for three β-lactam antibiotics, namely, ceftazidime, imipenem, and meropenem, was deciphered by screening a comprehensive PA14 mutant library for mutants with increased or reduced susceptibility to these antimicrobials. Confirmation of the phenotypes of all selected mutants was performed by Etest. Of the total of 78 confirmed mutants, 41 demonstrated a reduced susceptibility phenotype and 37 a supersusceptibility (i.e., altered intrinsic resistance) phenotype, with 6 mutants demonstrating a mixed phenotype, depending on the antibiotic. Only three mutants demonstrated reduced (PA0908) or increased (
glnK
and
ftsK
) susceptibility to all three antibiotics. Overall, the mutant profiles of susceptibility suggested distinct mechanisms of action and resistance for the three antibiotics despite their similar structures. More detailed analysis indicated important roles for novel and known β-lactamase regulatory genes, for genes with likely involvement in barrier function, and for a range of regulators of alginate biosynthesis.
Increased Temperature Enhances the Antimicrobial Effects of Daptomycin, Vancomycin, Tigecycline, Fosfomycin, and Cefamandole on Staphylococcal Biofilms
Authors: Hajdu Stefan , Holinka Johannes , Reichmann Sonja , Hirschl Alexander M. , Graninger Wolfgang , Presterl Elisabeth 
Published: August 2010

ABSTRACT

Implant-related infections are serious complications of trauma and orthopedic surgery and are most difficult to treat. The bacterial biofilms of 34 clinical
Staphylococcus
sp. isolates (
Staphylococcus aureus
,
n
= 14; coagulase-negative staphylococci,
n
= 19) were incubated with daptomycin (DAP; 5, 25, or 100 mg/liter), vancomycin (VAN; 5, 25, or 100 mg/liter), tigecycline (TGC; 1, 5, or 25 mg/liter), fosfomycin (FOM; 100, 250, or 1,000 mg/liter), and cefamandole (FAM; 50, 100, or 500 mg/liter) for 24 h at three different ambient temperatures: 35°C, 40°C, and 45°C. To quantify the reduction of the biomass, the optical density ratio (ODr) of stained biofilms and the number of growing bacteria were determined. Increasing the temperature to 45°C or to 40°C during incubation with FAM, FOM, TGC, VAN, or DAP led to a significant but differential reduction of the thickness of the staphylococcal biofilms compared to that at 35°C (
P
< 0.05). Growth reduction was enhanced for DAP at 100 mg/liter at 35°C, 40°C, and 45°C (log count reductions, 4, 3.6, and 3.3, respectively;
P
< 0.05). A growth reduction by 2 log counts was detected for FAM at a concentration of 500 mg/liter at 40°C and 45°C (
P
= 0.01). FOM at 1,000 mg/liter reduced the bacterial growth by 1.2 log counts (not significant). The antibacterial activity of antimicrobial agents is significantly but differentially enhanced by increasing the ambient temperature and using high concentrations. Adjuvant hyperthermia may be of value in the treatment of biofilm-associated implant-related infections.
Bioavailability and Population Pharmacokinetics of Voriconazole in Lung Transplant Recipients
Authors: Han Kelong , Capitano B. , Bies R. , Potoski B. A. , Husain S. , Gilbert S. , Paterson D. L. , McCurry K. , Venkataramanan R. 
Published: August 2010

ABSTRACT

This study was undertaken to characterize the pharmacokinetics and bioavailability of voriconazole in adult lung transplant patients during the early postoperative period, identify factors significantly associated with various pharmacokinetic parameters, and make recommendations for adequate dosing regimens. Thirteen lung transplant patients received two intravenous infusions (6 mg/kg, twice daily [b.i.d.]) immediately posttransplant followed by oral doses (200 mg, b.i.d.) for prophylaxis. Blood samples (9/interval) were collected during one intravenous and one oral dosing interval from each patient. Voriconazole plasma concentrations were measured by high-pressure liquid chromatography (HPLC). NONMEM was used to develop pharmacokinetic models, evaluate covariate relationships, and perform Monte Carlo simulations. There was a good correlation (
R
2
= 0.98) between the area under the concentration-time curve specific for the dose evaluated (AUC
0-∞
) and trough concentrations. A two-compartment model adequately described the data. Population estimates of bioavailability, clearance,

V
c

, and

V
p

were 45.9%, 3.45 liters/h, 54.7 liters, and 143 liters. Patients with cystic fibrosis (CF) exhibited a significantly lower bioavailability (23.7%,
n
= 3) than non-CF patients (63.3%,
n
= 10). Bioavailability increased with postoperative time and reached steady levels in about 1 week.

V
p

increased with body weight. Bioavailability of voriconazole is substantially lower in lung transplant patients than non-transplant subjects but significantly increases with postoperative time. CF patients exhibit significantly lower bioavailability and exposure of voriconazole and therefore need higher doses. Intravenous administration of voriconazole during the first postoperative day followed by oral doses of 200 mg or 400 mg appeared to be the optimal dosing regimen. However, voriconazole levels should be monitored, and the dose should be individualized based on trough concentrations as a good measure of drug exposure.
Limited Role of Secreted Aspartyl Proteinases Sap1 to Sap6 in
Candida albicans
Virulence and Host Immune Response in Murine Hematogenously Disseminated Candidiasis
Authors: Correia Alexandra , Lermann Ulrich , Teixeira Luzia , Cerca Filipe , Botelho Sofia , Gil da Costa Rui M. , Sampaio Paula , Gärtner Fátima , Morschhäuser Joachim , Vilanova Manuel , Pais Célia 
Published: August 2010

ABSTRACT

Candida albicans
secreted aspartyl proteinases (Saps) are considered virulence-associated factors. Several members of the Sap family were claimed to play a significant role in the progression of candidiasis established by the hematogenous route. This assumption was based on the observed attenuated virulence of
sap
-null mutant strains. However, the exclusive contribution of
SAP
genes to their attenuated phenotype was not unequivocally confirmed, as the Ura status of these mutant strains could also have contributed to the attenuation. In this study, we have reassessed the importance of
SAP1
to
SAP6
in a murine model of hematogenously disseminated candidiasis using
sap
-null mutant strains not affected in their
URA3
gene expression and compared their virulence phenotypes with those of Ura-blaster
sap
mutants. The median survival time of BALB/c mice intravenously infected with a mutant strain lacking
SAP1
to
SAP3
was equivalent to that of mice infected with wild-type strain SC5314, while those infected with mutant strains lacking
SAP5
showed slightly extended survival times. Nevertheless, no differences could be observed between the wild type and a Δ
sap456
mutant in their abilities to invade mouse kidneys. Likewise, a deficiency in
SAP4
to
SAP6
had no noticeable impact on the immune response elicited in the spleens and kidneys of
C. albicans
-infected mice. These results contrast with the behavior of equivalent Ura-blaster mutants, which presented a significant reduction in virulence. Our results suggest that Sap1 to Sap6 do not play a significant role in
C. albicans
virulence in a murine model of hematogenously disseminated candidiasis and that, in this model, Sap1 to Sap3 are not necessary for successful
C. albicans
infection.