bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cerebrospinal fluid levels of catecholamines and its metabolites in Parkinson's disease: effect of l‐DOPA treatment and changes in levodopa‐induced dyskinesia
Authors: Andersen Andreas Dammann , Blaabjerg Morten , Binzer Michael , Kamal Akram , Thagesen Helle , Kjaer Troels Wesenberg , Stenager Egon , Gramsbergen Jan Bert Paul 
Published: February 2017

AbstractLevodopa (l‐DOPA, l‐3,4‐dihydroxyphenylalanine) is the most effective drug in the symptomatic treatment of Parkinson's disease (PD), but chronic use initiates a maladaptive process leading to l‐DOPA‐induced dyskinesia (LID). Risk factors for early onset LID include younger age, more severe disease at baseline and higher daily l‐DOPA dose, but biomarkers to predict the risk of motor complications are not yet available. Here, we investigated whether CSF levels of catecholamines and its metabolites are altered in PD patients with LID [PD‐LID, n = 8)] as compared to non‐dyskinetic PD patients receiving l‐DOPA (PD‐L, n = 6), or not receiving l‐DOPA (PD‐N, n = 7) as well as non‐PD controls (n = 16). PD patients were clinically assessed using the Unified Parkinson's Disease Rating Scale and Unified Dyskinesia Rating Scale and CSF was collected after overnight fasting and 1–2 h after oral intake of l‐DOPA or other anti‐Parkinson medication. CSF catecholamines and its metabolites were analyzed by HPLC with electrochemical detection. We observed (i) decreased levels of dihydroxyphenylacetic acid (DOPAC) and homovanillic acid in PD patients not receiving l‐DOPA (ii) higher dopamine (DA) levels in PD‐LID as compared to controls (iii) higher DA/l‐DOPA and lower DOPAC/DA ratio's in PD‐LID as compared to PD‐L and (iv) an age‐dependent increase of DA and decrease of DOPAC/DA ratio in controls. These results suggest increased DA release from non‐DA cells and deficient DA re‐uptake in PD‐LID. Monitoring DA and DOPAC in CSF of l‐DOPA‐treated PD patients may help identify patients at risk of developing LID.
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Influence of culture on pain comorbidity in women with and without temporomandibular disorder‐pain
Authors: Al‐Harthy M. , Michelotti A. , List T. , Ohrbach R. 
Published: February 2017

SummaryEvidence on cultural differences in prevalence and impact of common chronic pain conditions, comparing individuals with temporomandibular disorders (TMD) versus individuals without TMD, is limited. The aim was to assess cross‐cultural comorbid pain conditions in women with chronic TMD pain. Consecutive women patients (n = 122) with the index condition of chronic TMD pain diagnosed per the research diagnostic criteria for TMD and TMD‐free controls (n = 121) matched for age were recruited in Saudi Arabia, Italy and Sweden. Self‐report questionnaires assessed back, chest, stomach and head pain for prevalence, pain intensity and interference with daily activities. Logistic regression was used for binary variables, and ancova was used for parametric data analysis, adjusting for age and education. Back pain was the only comorbid condition with a different prevalence across cultures; Swedes reported a lower prevalence compared to Saudis (P < 0·01). Saudis reported higher prevalence of work reduced >50% due to back pain compared to Italians or Swedes (P < 0·01). Headache was the most common comorbid condition in all three cultures. The total number of comorbid conditions did not differ cross‐culturally but were reported more by TMD‐pain cases than TMD‐free controls (P < 0·01). For both back and head pain, higher average pain intensities (P < 0·01) and interference with daily activities (P < 0·01) were reported by TMD‐pain cases, compared to TMD‐free controls. Among TMD‐pain cases, Italians reported the highest pain‐related disability (P < 0·01). Culture influences the associated comorbidity of common pain conditions. The cultural influence on pain expression is reflected in different patterns of physical representation.
Algal light sensing and photoacclimation in aquatic environments
Authors: Duanmu Deqiang , Rockwell Nathan C. , Lagarias J. Clark 
Published: February 2017

AbstractAnoxygenic photosynthetic prokaryotes arose in ancient oceans ~3.5 billion years ago. The evolution of oxygenic photosynthesis by cyanobacteria followed soon after, enabling eukaryogenesis and the evolution of complex life. The Archaeplastida lineage dates back ~1.5 billion years to the domestication of a cyanobacterium. Eukaryotic algae have subsequently radiated throughout oceanic/freshwater/terrestrial environments, adopting distinctive morphological and developmental strategies for adaptation to diverse light environments. Descendants of the ancestral photosynthetic alga remain challenged by a typical diurnally fluctuating light supply ranging from ~0 to ~2000 μE m−2 s−1. Such extreme changes in light intensity and variations in light quality have driven the evolution of novel photoreceptors, light‐harvesting complexes and photoprotective mechanisms in photosynthetic eukaryotes. This minireview focuses on algal light sensors, highlighting the unexpected roles for linear tetrapyrroles (bilins) in the maintenance of functional chloroplasts in chlorophytes, sister species to streptophyte algae and land plants.
The Role of Affect in Attitude Formation toward New Technologies: The Case of Stratospheric Aerosol Injection
Authors: Merk Christine , Pönitzsch Gert 
Published: February 2017

AbstractThis article analyzes determinants of technology acceptance and their interdependence. It highlights the role of affect in attitude formation toward new technologies and examines how it mediates the influence of stable psychological variables on the technology's acceptability. Based on theory and previous empirical evidence, we develop an analytical framework of attitude formation. We test this framework using survey data on attitudes toward stratospheric aerosol injection (SAI), a technology that could be used to counteract global warming. We show that affect is more important than risk and benefit perception in forming judgment about SAI. Negative and positive affect directly alter the perception of risks and benefits of SAI and its acceptability. Furthermore, affect is an important mediator between stable psychological variables—such as trust in governmental institutions, values, and attitudes—and acceptability. A person's affective response is thus guided by her general attitudes and values.
Joint Non-Parametric Correction Estimator for Excess Relative Risk Regression in Survival Analysis with Exposure Measurement Error
Authors: Wang Ching-Yun , Cullings Harry , Song Xiao , Kopecky Kenneth J. 
Published: February 2017

Summary
Observational epidemiological studies often confront the problem of estimating exposure–disease relationships when the exposure is not measured exactly. We investigate exposure measurement error in excess relative risk regression, which is a widely used model in radiation exposure effect research. In the study cohort, a surrogate variable is available for the true unobserved exposure variable. The surrogate variable satisfies a generalized version of the classical additive measurement error model, but it may or may not have repeated measurements. In addition, an instrumental variable is available for individuals in a subset of the whole cohort. We develop a non-parametric correction estimator by using data from the subcohort and further propose a joint non-parametric correction estimator using all observed data to adjust for exposure measurement error. An optimal linear combination estimator of the joint non-parametric correction and non-parametric correction is further developed. The estimators proposed are non-parametric, which are consistent without imposing a covariate or error distribution, and are robust to heteroscedastic errors. Finite sample performance is examined via a simulation study. We apply the developed methods to data from the Radiation Effects Research Foundation, in which chromosome aberration is used to adjust for the effects of radiation dose measurement error on the estimation of radiation dose responses.
Spectral Stability for Classical Periodic Waves of the Ostrovsky and Short Pulse Models
Authors: Hakkaev S. , Stanislavova M. , Stefanov A. 
Published: February 2017

AbstractWe consider the Ostrovsky and short pulse models in a symmetric spatial interval, subject to periodic boundary conditions. For the Ostrovsky case, we rederive the formulas for the classical periodic traveling waves, while for the short pulse model, we explicitly construct traveling waves in terms of Jacobi elliptic functions. In both cases, we show spectral stability, for all values of the parameters. This is achieved by studying the nonstandard eigenvalue problems in the form , where is a Hill operator.
Effects of eIFiso4G1 mutation on seed oil biosynthesis
Authors: Li Qiang , Shen Wenyun , Zheng Qian , Tan Yifang , Gao Jie , Shen Jinxiong , Wei Yangdou , Kunst Ljerka , Zou Jitao 
Published: February 2017

SummaryFatty acid biosynthesis is a primary metabolic pathway that occurs in plastids, whereas the formation of glycerolipid molecules for the majority of cellular membrane systems and the deposition of storage lipid in seeds takes place in the cytosolic compartment. In this report, we present a study of an Arabidopsis mutant, ar21, with a novel seed fatty acid phenotype showing higher contents of eicosanoic acid (20:1) and oleic acid (18:1) and a reduced level of α‐linolenic acid (18:3). A combination of map‐based cloning and whole‐genome sequencing identified the genetic basis underlying the fatty acid phenotype as a lesion in the plant‐specific eukaryotic translation initiation factor eIFiso4G1. Transcriptome analysis on developing seeds revealed a reduced level of plastid‐encoded genes. Specifically, decreases in both transcript and protein levels of an enzyme involved in fatty acid biosynthesis, the β‐subunit of the plastidic heteromeric acetyl‐CoA carboxylase (htACCase) encoded by accD, were evident in the mutant. Biochemical assays showed that the developing seeds of the mutant possessed a decreased htACCase activity in the plastid but an elevated activity of homomeric acetyl‐CoA carboxylase (hmACCase). These results suggested that the increased 20:1 was attributable at least in part to the enhanced cytosolic hmACCase activity. We also detected a significant repression of FATTY ACID DESATURASE 3 (FAD3) during seed development, which correlated with a decreased 18:3 level in seed oil. Together, our study on a mutant of eIFiso4G1 uncovered multifaceted interactions between the cytosolic and plastidic compartments in seed lipid biosynthesis that impact major seed oil traits.
Cascade of chromosomal rearrangements caused by a heterogeneous T‐DNA integration supports the double‐stranded break repair model for T‐DNA integration
Authors: Hu Yufei , Chen Zhiyu , Zhuang Chuxiong , Huang Jilei 
Published: February 2017

SummaryTransferred DNA (T‐DNA) from Agrobacterium tumefaciens can be integrated into the plant genome. The double‐stranded break repair (DSBR) pathway is a major model for T‐DNA integration. From this model, we expect that two ends of a T‐DNA molecule would invade into a single DNA double‐stranded break (DSB) or independent DSBs in the plant genome. We call the later phenomenon a heterogeneous T‐DNA integration, which has never been observed. In this work, we demonstrated it in an Arabidopsis T‐DNA insertion mutant seb19. To resolve the chromosomal structural changes caused by T‐DNA integration at both the nucleotide and chromosome levels, we performed inverse PCR, genome resequencing, fluorescence in situ hybridization and linkage analysis. We found, in seb19, a single T‐DNA connected two different chromosomal loci and caused complex chromosomal rearrangements. The specific break‐junction pattern in seb19 is consistent with the result of heterogeneous T‐DNA integration but not of recombination between two T‐DNA insertions. We demonstrated that, in seb19, heterogeneous T‐DNA integration evoked a cascade of incorrect repair of seven DSBs on chromosomes 4 and 5, and then produced translocation, inversion, duplication and deletion. Heterogeneous T‐DNA integration supports the DSBR model and suggests that two ends of a T‐DNA molecule could be integrated into the plant genome independently. Our results also show a new origin of chromosomal abnormalities.
Dosimetric evaluation of the Acuros XB algorithm for a 4 MV photon beam in head and neck intensity‐modulated radiation therapy
Authors: Hirata Kimiko , Nakamura Mitsuhiro , Yoshimura Michio , Mukumoto Nobutaka , Nakata Manabu , Ito Hitoshi , Inokuchi Haruo , Matsuo Yukinori , Mizowaki Takashi , Hiraoka Masahiro 
Published: February 2017

In this study, we assessed the differences in the dose distribution of a 4 MV photon beam among different calculation algorithms: the Acuros XB (AXB) algorithm, the analytic anisotropic algorithm (AAA), and the pencil beam convolution (PBC) algorithm (ver. 11.0.31), in phantoms and in clinical intensity‐modulated radiation therapy (IMRT) plans. Homogeneous and heterogeneous, including middle‐, low‐, and high‐density, phantoms were combined to assess the percentage depth dose and lateral dose profiles among AXB, AAA, and PBC. For the phantom containing the low‐density area, AXB was in agreement with measurement within 0.5%, while the greatest differences between the AAA and PBC calculations and measurement were 2.7% and 3.6%, respectively. AXB showed agreement with measurement within 2.5% at the high‐density area, while AAA and PBC overestimated the dose by more than 4.5% and 4.0%, respectively. Furthermore, 15 IMRT plans, calculated using AXB, for oropharyngeal, hypopharyngeal, and laryngeal carcinomas were analyzed. The dose prescription was 70 Gy to 50% of the planning target volume (). Subsequently, each plan was recalculated using AAA and PBC while maintaining the AXB‐calculated monitor units, leaf motion, and beam arrangement. Additionally, nine hypopharyngeal and laryngeal cancer patients were analyzed in terms of for cartilaginous structures (). The doses covering 50% to calculated by AAA and PBC were and significantly higher than those using AXB, respectively (). The increases in doses to calculated by AAA and PBC relative to AXB were 3.9% and 5.3% on average, respectively, and were relatively greater than those in the entire . AXB was found to be in better agreement with measurement in phantoms in heterogeneous areas for the 4 MV photon beam. Considering AXB as the standard, AAA and PBC overestimated the IMRT dose for head and neck cancer. The dosimetric differences should not be ignored, particularly with cartilaginous structures in PTV.PACS number: 87.55.‐x, 87.55.dk, 87.55.kd
Robotic radiosurgery system patient‐specific QA for extracranial treatments using the planar ion chamber array and the cylindrical diode array
Authors: Lin Mu‐Han , Veltchev Iavor , Koren Sion , Ma Charlie , Li Jinsgeng 
Published: February 2017

Robotic radiosurgery system has been increasingly employed for extracranial treatments. This work is aimed to study the feasibility of a cylindrical diode array and a planar ion chamber array for patient‐specific QA with this robotic radiosurgery system and compare their performance. Fiducial markers were implanted in both systems to enable image‐based setup. An in‐house program was developed to postprocess the movie file of the measurements and apply the beam‐by‐beam angular corrections for both systems. The impact of noncoplanar delivery was then assessed by evaluating the angles created by the incident beams with respect to the two detector arrangements and cross‐comparing the planned dose distribution to the measured ones with/without the angular corrections. The sensitivity of detecting the translational (1–3 mm) and the rotational (1°–3°) delivery errors were also evaluated for both systems. Six extracranial patient plans (PTV 7–137 cm3) were measured with these two systems and compared with the calculated doses. The plan dose distributions were calculated with ray‐tracing and the Monte Carlo (MC) method, respectively. With 0.8 by 0.8 mm2 diodes, the output factors measured with the cylindrical diode array agree better with the commissioning data. The maximum angular correction for a given beam is 8.2% for the planar ion chamber array and 2.4% for the cylindrical diode array. The two systems demonstrate a comparable sensitivity of detecting the translational targeting errors, while the cylindrical diode array is more sensitive to the rotational targeting error. The MC method is necessary for dose calculations in the cylindrical diode array phantom because the ray‐tracing algorithm fails to handle the high‐Z diodes and the acrylic phantom. For all the patient plans, the cylindrical diode array/ planar ion chamber array demonstrate passing rates. The feasibility of using both systems for robotic radiosurgery system patient‐specific QA has been demonstrated. For gamma evaluation, criteria for cylindrical diode array and criteria for planar ion chamber array are suggested. The customized angular correction is necessary as proven by the improved passing rate, especially with the planar ion chamber array system.PACS number: 29.40.‐n
Utilization of optical tracking to assess efficacy of intracranial immobilization techniques in proton therapy
Authors: His Wen C. , Schreuder Andries N. , Zeidan Omar 
Published: February 2017

We present a quantitative methodology to measure head interfraction movements within intracranial masks of commercial immobilization devices used for proton radiotherapy. A three‐points tracking (3PtTrack) method was developed to measure the mask location for each treatment field over an average of 10 fractions for seven patients. Five patients were treated in supine with the Qfix Base‐of‐Skull (BoS) headframe, and two patients were treated in prone with the CIVCO Uni‐frame baseplate. Patients were first localized by an in‐room, image‐guidance (IG) system, and then the mask location was measured using the 3PtTrack method. Measured mask displacements from initial location at the first fraction are considered equivalent to the head interfraction movement within the mask. The trends of head movements and couch displacements and rotation were analyzed in three major directions. The accuracy of 3PtTrack method was shown to be within 1.0 mm based on daily measurements of a QA device after localization by the IG system for a period of three months. For seven patients, mean values of standard deviation (SD) in anterior–posterior, lateral, and superior–inferior directions were 1.1 mm, 1.4 mm, and 1.6 mm for head movements, and were 1.4 mm, 1.8 mm, and 3.4 mm for couch displacements. The mean SD values of couch rotations were 1.1°, 0.9°, and 1.1° for yaw, pitch, and roll, respectively. The overall patterns of head movements and couch displacements were similar for patients treated in either supine or prone, with larger deviations in the superior–inferior (SI) direction. A suboptimal mask fixation to the frame of the mask to the H&N frame is likely the cause for the observed larger head movements and couch displacements in the SI direction compared to other directions. The optical‐tracking methodology provided a quantitative assessment of the magnitude of head motion.PACS number: 87.55.km
Optimum radiation source for radiation therapy of skin cancer
Authors: Safigholi Habib , Song William Y. , Meigooni Ali S. 
Published: February 2017

Several different applicators have been designed for treatment of skin cancers, such as scalp, hand, and legs using Ir‐192 HDR brachytherapy sources (IR‐HDRS), miniature electronic brachytherapy sources (eBT), and external electron beam radiation therapy (EEBRT). Although, all of these methodologies may deliver the desired radiation dose to the skin, but the dose to the underlying bone may become the limiting factor for selection of the optimum treatment technique. In this project, dose to the underlying bone has been evaluated as a function of the radiation type, thickness of the bone, and thickness of the soft tissue on top of bone, assuming the same radiation dose delivery to the skin. These evaluations are performed using Monte Carlo (MC) simulation technique with MCNP5 code. The results of these investigations indicate that, for delivery of the same skin dose with a 50 keV eBT, 4 MeV or 6 MeV EEBRT techniques, the average doses received by the underlying bones are 5.31, 2, or 1.75 times the dose received from IR‐HDRS technique, respectively. These investigations indicate that, for the treatment of skin cancer condition with bone immediately beneath skin, the eBT technique may not be the most suitable technique, as it may lead to excessive bone dose relative to IR‐HDRS and 6 MeV or 4 MeV electron beams.PACS number: 87.53.Jw, 87.55.K‐
AAPM Medical Physics Practice Guideline 5.a.: Commissioning and QA of Treatment Planning Dose Calculations — Megavoltage Photon and Electron Beams
Authors: Smilowitz Jennifer B. , Das Indra J. , Feygelman Vladimir , Fraass Benedick A. , Kry Stephen F. , Marshall Ingrid R. , Mihailidis Dimitris N. , Ouhib Zoubir , Ritter Timothy , Snyder Michael G. , Fairobent Lynne 
Published: February 2017

The American Association of Physicists in Medicine (AAPM) is a nonprofit professional society whose primary purposes are to advance the science, education and professional practice of medical physics. The AAPM has more than 8,000 members and is the principal organization of medical physicists in the United States.The AAPM will periodically define new practice guidelines for medical physics practice to help advance the science of medical physics and to improve the quality of service to patients throughout the United States. Existing medical physics practice guidelines will be reviewed for the purpose of revision or renewal, as appropriate, on their fifth anniversary or sooner.Each medical physics practice guideline represents a policy statement by the AAPM, has undergone a thorough consensus process in which it has been subjected to extensive review, and requires the approval of the Professional Council. The medical physics practice guidelines recognize that the safe and effective use of diagnostic and therapeutic radiology requires specific training, skills, and techniques, as described in each document. Reproduction or modification of the published practice guidelines and technical standards by those entities not providing these services is not authorized.The following terms are used in the AAPM practice guidelines:

Must and Must Not: Used to indicate that adherence to the recommendation is considered necessary to conform to this practice guideline.
Should and Should Not: Used to indicate a prudent practice to which exceptions may occasionally be made in appropriate circumstances.