bluuebunny/crossref_metadata_2025_split huggingface dataset:
Measurement and Simulation of the Counting Efficiency of a Whole-body Counter Using a BOMAB Phantom Inserted with Rod Sources Containing Mixed Radionuclides
Authors: Park MinSeok , Yoo Jaeryong , Ha Wi-Ho , Park Sunhoo , Jin Young Woo 
Published: January 2018

Abstract
The examination of internal contamination is important for providing an adequate medical response during a radiological emergency. A whole-body counting system can assess gamma-emitting radionuclides in a human body when monitoring internal contamination. It is necessary to calibrate whole-body counting systems by using a calibration phantom, such as a Bottle Manikin Absorption phantom, to properly assess internal contamination. However, the total weight of the Bottle Manikin Absorber phantom is high, and there can be leakage of radioactive sources, which are disadvantages of using such a phantom. This study proposes a calibration phantom that is designed to overcome these disadvantages. The proposed phantom consists of rod sources that are inserted in each part of the phantom. The counting efficiency of the rod-source-inserted calibration phantom was acquired using a Monte Carlo simulation method, but the results were evaluated by comparing the experimental efficiencies with those of a conventional Bottle Manikin Absorption phantom by using two commercial whole-body counting systems (stand-up type and bed type). The efficiency curve of the rod-source-inserted phantom matched well that of the conventional calibration phantom. The relative deviation between the efficiencies of the conventional Bottle Manikin Absorption phantom and the proposed calibration phantom in both whole-body counting systems was less than 11%, and the total weight of the phantom was also reduced. These results suggest that the proposed phantom can be manipulated more easily and replace the conventional Bottle Manikin Absorption calibration phantom for these two types of whole-body counting systems.
Application of the ICRP 67 and NCRP 156 Biokinetic Models to 241 Am Wound Data from Nonhuman Primates
Authors: Alomairy Nada A. , Brey Richard R. , Guilmette Raymond A. 
Published: January 2018

Abstract
Distribution, retention, and excretion of intramuscularly injected 241Am citrate have been investigated in cynomolgus and rhesus nonhuman primates (NHP). Bioassay and retention data, obtained from experiments done by Patricia Durbin and her colleagues at Lawrence Berkeley National Laboratory, were evaluated against the International Commission on Radiological Protection (ICRP 67) 241Am systemic model coupled with to the National Council on Radiation Protection and Measurement wound model (NCRP 156). The default transfer rates suggested in these models were used with the urine and feces excretion data to predict the intake as well as liver and skeleton tissue contents at the time of death. The default models adequately predict the animals’ urine bioassay data, but the injected activities were overpredicted by as much 4.41 times and underpredicted by as much as 0.99 times. Poor prediction has been observed in all cases using fecal excretion. The retained activity in the liver and skeleton were investigated using the same approach. It appears that the models predict the amount of the activity retention in the skeleton more accurately than in the liver. The fraction of predicted to measured activity at the time of death in the skeleton was over 1.0 in most cases, and accurate predictions were obtained in seven cases. The predicted activity in skeleton for these cases ranged from 2.7 to 17% overestimated activity and from 9 to 14% underestimated activity. NHPs’ urine data and organ retention were compared with data from previously modeled baboons and beagle dogs. About 6% of the injected activity in baboons and beagle dog was excreted in urine and approximately 0.1% in feces in the first 24 h. The results from NHP are not different from excreta analysis in these other species. Urinary excretion in the cynomolgus, rhesus, and baboon NHP is the dominant pathway of 241Am clearance; however, fecal excretion is considered dominant in beagle dogs. The comparison between NHPs and humans is difficult due to the differences in the number of activities translocated or deposited in the liver tissue and nonliver tissues (primarily skeleton), in addition to the physiological differences between the NHPs and humans.
Deterministic Effects to the Lens of the Eye Following Ionizing Radiation Exposure
Authors: Thome Christopher , Chambers Douglas B. , Hooker Antony M. , Thompson Jeroen W. , Boreham Douglas R. 
Published: January 2018

Abstract
Ionizing radiation exposure to the lens of the eye is a known cause of cataractogenesis. Historically, it was believed that the acute threshold dose for cataract formation was 5 Sv, and annual dose limits to the lens were set at 150 mSv. Recently, however, the International Commission on Radiological Protection has reduced their threshold dose estimate for deterministic effects to 0.5 Gy and is now recommending an occupational limit of 20 mSv per year on average. A number of organizations have questioned whether this new threshold and dose limit are justified based on the limited reliable data concerning radiation-induced cataracts. This review summarizes all of the published human epidemiological data on ionizing radiation exposure to the lens of the eye in order to evaluate the proposed threshold. Data from a variety of exposure cohorts are reviewed, including atomic bomb survivors, Chernobyl liquidators, medical workers, and radiotherapy patients. Overall, there is not conclusive evidence that the threshold dose for cataract formation should be reduced to 0.5 Gy. Many of the studies reviewed here are challenging to incorporate into an overall risk model due to inconsistencies with dosimetry, sample size, and scoring metrics. Additionally, risk levels in the studied cohorts may not relate to occupational scenarios due to differences in dose rate, radiation quality, age at exposure and latency period. New studies should be designed specifically focused on occupational exposures, with reliable dosimetry and grading methods for lens opacities, to determine an appropriate level for dose threshold and exposure limit.
Silicone Hydrogel and Rigid Gas-Permeable Scleral Lens Tear Exchange
Authors: Paugh Jerry R. , Chen Elaine , Heinrich Colton , Miller Heidi , Gates Tiffany , Nguyen Andrew Loc , Edrington Timothy , Weissman Barry A. 
Published: January 2018

Objectives:
To quantify tear elimination rate (ER) underneath silicone hydrogel (Si-Hy) and scleral gas permeable (GP) contact lenses (CLs).

Methods:
Subjects successfully using either well-fitting soft Si-Hy CLs or scleral GP CLs were recruited. Most scleral GP CL wearers had irregular corneas (e.g., keratoconus). An objective fluorometer measured decay of fluorescein isothiocyanate dextran dye signal (70 kD MW) from which the tear ER in %/min was calculated. For GP scleral lenses, the ER was determined for both the initial settling period and the 30- to 60-min period, and without lenses. All ERs were calculated from 5 to 30 min to avoid reflex tearing effects.

Results:
Fourteen soft Si-Hy CL and 12 scleral GP CL wearers completed the study. The ER for the scleral GP CL wearers averaged 0.57 (±0.6) %/min for the 0- to 30-min and 0.42 (±0.5) %/min for the 30- to 60-min period (P=0.515). Non-CL wear tear ER in these same subjects averaged 34.17 (±15.9) %/min and was significantly different versus both scleral GP wear periods (both P values <0.001). The ER for the soft Si-Hy CL wearers, 5 to 30 min, averaged 6.09 (±2.8) %/min.

Conclusions:
Our data demonstrate significantly less ER in well-fit scleral GP CL wearers compared with soft Si-Hy CL wearers for both the settling and longer wear periods (both P values <0.001). Moreover, slightly greater tear exchange was observed during the scleral GP CL settling period than later, which may reflect a change over time in tear vault thickness.
Consequences of Preservative Uptake and Release by Contact Lenses
Authors: Morris Carol A. , Maltseva Inna A. , Rogers Victoria A. , Ni Jing , Khong Kathleen T. , Derringer Charles B. , George Melanie D. , Luk Andrew S. 
Published: January 2018

Objectives:
To assess contact lens preservative uptake and release from multipurpose solutions (MPS) and subsequent acquisition of lens antibacterial activity.

Methods:
Kinetics of uptake and release of poly (hexamethylene biguanide hydrochloride) (PHMB) or polyquaternium-1 (PQ-1) from various contact lenses were studied initially with the pure compounds and then after soaking in MPS containing these compounds. Lenses soaked in MPS were tested for antibacterial activity.

Results:
Only lenses with a negatively charged component absorbed these preservatives. For lenses containing methacrylic acid (MA), uptake of PHMB from preservative-only solution was fast, yet little was released, in contrast to its rapid release from lenses containing other anionic groups. This trend persisted with PHMB-containing MPS. PQ-1 from preservative-only solution was only absorbed by lenses containing MA and was released from MA-containing hydrogels, but not significantly from an MA-containing silicone hydrogel. Lens uptake of PQ-1 was much lower from MPS and release was essentially undetectable from all lenses evaluated. Antibacterial lens activity was acquired by lenses containing MA after an overnight soak in MPS containing PQ-1, and for balafilcon A and omafilcon A after 5 exchanges in PHMB-containing MPS. Acquired activity was maintained during cycling between artificial tear protein solution and MPS.

Conclusions:
Lens preservative uptake and its subsequent release are dependent on lens chemistry, preservative nature, and other MPS components. A few lens/solution combinations acquired antibacterial activity after one or more overnight soaks in MPS, depending on the nature of the anionic lens component and the preservative. Uncharged lenses did not acquire antibacterial activity.
Long-term Prognosis of Acute-on-Chronic Liver Failure Survivors
Authors: Yoon Eileen L. , Kim Tae Yeob , Lee Chang Hyeong , Kim Tae Hun , Cho Hyun Chin , Lee Sang Soo , Kim Sung Eun , Kim Hee Yeon , Kim Chang Wook , Song Do Seon , Yang Jin Mo , Sinn Dong Hyun , Jung Young Kul , Yim Hyung Joon , Kim Hyoung Su , Sohn Joo Hyun , Kim Jeong Han , Choe Won Hyeok , Lee Byung Seok , Kim Moon Young , Jeong Soung Won , Choi Eunhee , Kim Dong Joon 
Published: January 2018

Goals:
We aimed to investigate significant factors influencing the long-term prognosis of patients who survived acute-on-chronic liver failure (ACLF).

Background:
The mortality of ACLF is predominantly affected by the organ failure severity. However, long-term outcomes of patients who survive ACLF are not known.

Study:
A cohort of 1084 cirrhotic patients who survived for more than 3 months following acute deterioration of liver function was prospectively followed. ACLF was defined by the European Association for the Study of the Liver Chronic Liver Failure Consortium definition.

Results:
The mean follow-up duration was 19.4±9.9 months. In the subgroup of patients without previous acute decompensation (AD), ACLF occurrence did not affect long-term outcomes. However, in patients with previous AD, ACLF negatively affected long-term transplant-free survival even after overcoming ACLF (hazard ratio, 2.00, P=0.012). Previous AD was the significant predictive factor of long-term mortality and was independent of the Model for End-stage Liver Disease score in these ACLF-surviving patients. Organ failure severity did not affect transplant-free survival in patients who survived an ACLF episode.

Conclusions:
A prior history of AD is the most important factor affecting long-term outcomes following an ACLF episode regardless of Model for End-stage Liver Disease score. Prevention of a first AD episode may improve the long-term transplant-free survival of liver cirrhosis patients.
Free flaps for head and neck cancer in paediatric and neonatal patients
Authors: Elledge Ross , Parmar Satyesh 
Published: January 2018

Purpose of review
To review recent literature on the subject of free tissue transfer options in paediatric head and neck surgery, with a particular emphasis on highlighting the advantages and disadvantages of different reconstructions in the paediatric patient.

Recent findings
Free tissue transfer in paediatric patients is predictable and applicable for a wide range of congenital and acquired defects in the head and neck. The free fibula flap is a mainstay of mandibular reconstruction and allows excellent implant-supported prosthodontic rehabilitation and growth potential at the recipient site with little or no donor site morbidity. Other less commonly explored options include the deep circumflex iliac artery flap, scapula flap and medial femoral condyle flap. The gracilis mucle remains the mainstay for facial reanimation with other options including pectoralis minor, rectus abdominis, extensor digitorum brevis and latissimus dorsi. There are compelling arguments for centralization of services and creative strategies in postoperative rehabilitation (e.g. play therapy).

Summary
Free flaps in paediatric patients are a viable option and may even have advantages relative to adults because of the absence of atherosclerosis, purported lower risk of vasospasm and proportionally larger vessel size. Transfer earlier in life maximizes functional potential and ‘normalizes’ treatment.
Applications of near infrared spectroscopy in the neonate
Authors: Garvey Aisling A. , Dempsey Eugene M. 
Published: January 2018

Purpose of review
There has been a significant increase in the utilization of NIRS in neonatal care over the last few years, with some centers now routinely utilizing this monitoring technique for direct intervention at the bedside. In this review, we provide a summary of the most up-to-date evidence on near infrared spectroscopy utilization, with particular emphasis on measurement of cerebral oxygenation in preterm infants.

Recent findings
There have been significant advances in the technology, leading to an increase in the number of available devices and in the use of this monitoring tool to reduce cerebral injury in preterm infants. The role of NIRS in assessing cerebral autoregulation in preterm and term infants, in evaluating somatic oxygenation, and in the management of newborns with hypoxic ischaemic encephalopathy is discussed.

Summary
Two recent pilot randomized controlled trials highlight the potential of cerebral oxygenation monitoring to direct management in the delivery room and the neonatal intensive care unit. However, we urge caution against routine use and await the results of further studies in this area before considering this type of monitoring as standard of care.
Preclinical Data Supporting Antitumor Activity of PD-1 Blockade
Authors: Curran Michael A. 
Published: January 2018

Abstract
Antibodies that block the PD-1 coinhibitory receptor on T cells or its primary ligand, PD-L1, have demonstrated unprecedented efficacy across a diverse array of both solid and hematologic malignancies in the clinic. These advances were built on a foundation of murine preclinical tumor model studies, which both demonstrated the therapeutic potential of PD-1/PD-L1 antibody blockade and also provided critical insights into the cellular and molecular processes underlying their capacity to elicit immune-mediated tumor regressions. As the field of immunotherapy moves toward higher-order combinations of agents, effective utilization of murine tumor models to optimize the composition of PD-1 antibody combination therapies, as well as their dosing and scheduling, will be essential for effective clinical translation. Novel murine models bearing human tumor xenografts and engrafted human immune systems may help close the gap between preclinical and clinical immunobiology.
Combination Strategies PD-1/PD-L1 Antagonists
Authors: Sznol Mario 
Published: January 2018

Abstract
Despite the broad clinical antitumor activity of PD-1/PD-L1 antagonists, many patients who are treated with these agents either do not respond or achieve suboptimal responses. Improving overall outcome will require combinations with other agents to address potential innate or acquired mechanisms of resistance. Many combination trials have been initiated in patients with or without prior exposure to the PD-1/PD-L1 antagonists. In addition to the challenge of identifying optimal dose, schedule, and sequence for the combinations, current biomarker efforts lack the precision to identify optimal combination partners for the PD-1/PD-L1 antagonists in individual patients. For each possible combination, careful consideration of clinical trial design, biomarker strategies, and endpoints for early clinical development will be necessary to move the most promising regimens forward and therefore to accelerate the rate of clinical progress.
The Influence of Environmental Enrichment on Cardiovascular and Behavioral Responses to Social Stress
Authors: Normann Marigny C. , McNeal Neal , Dagner Ashley , Ihm Elliott , Woodbury Matthew , Grippo Angela J. 
Published: January 2018

ABSTRACT

Objective
Stress is linked to negative cardiovascular consequences and increases in depressive behaviors. Environmental enrichment (EE) involves exposure to novel items that provide physical and cognitive stimulation. EE has behavioral, cognitive, and neurobiological effects that may improve stress responses in humans and animal models. This study investigated the potential protective effects of EE on behavior and cardiovascular function in female prairie voles after a social stressor.

Methods
Radiotelemetry transmitters were implanted into female prairie voles to measure heart rate (HR) and heart rate variability (HRV) throughout the study. All females were paired with a male partner for 5 days, followed by separation from their partner for 5 additional days, and a 10-day treatment period. Treatment consisted of continued isolation, isolation with EE, or re-pairing with the partner (n = 9 per group). After treatment, animals were observed in the forced swim test (FST) for measures of stress coping behaviors.

Results
Isolation elevated HR and reduced HRV relative to baseline for all groups (p < .001). HR and HRV returned to baseline in the EE and re-paired groups, but not in the continued isolation group (p < .001). Animals in the EE and re-paired groups displayed significantly lower immobility time (p < .001) and HR (p < .03) during the FST, with a shorter latency for HR to return to baseline levels after the FST, relative to the continued isolation group (p < .001).

Conclusions
EE and re-pairing reversed the negative behavioral and cardiovascular consequences associated with social isolation.
Vacuum stability in the early universe and the backreaction of classical gravity
Authors: Markkanen Tommi 
Published: January 2018

In the case of a metastable electroweak vacuum, the quantum corrected effective potential plays a crucial role in the potential instability of the standard model. In the early universe, in particular during inflation and reheating, this instability can be triggered leading to catastrophic vacuum decay. We discuss how the large space-time curvature of the early universe can be incorporated in the calculation and in many cases significantly modify the flat space prediction. The two key new elements are the unavoidable generation of the non-minimal coupling between the Higgs field and the scalar curvature of gravity and a curvature induced contribution to the running of the constants. For the minimal set up of the standard model and a decoupled inflation sector we show how a metastable vacuum can lead to very tight bounds for the non-minimal coupling. We also discuss a novel and very much related dark matter generation mechanism.
This article is part of the Theo Murphy meeting issue ‘Higgs cosmology’.
Synthetic stimuli reveal a predictive and switch-like activation of the songbird’s vocal motor program
Authors: Bush Alan , Döppler Juan F. , Goller Franz , Mindlin Gabriel B. 
Published: January 2018

AbstractAcquisition and maintenance of complex vocal behaviors like human speech and oscine birdsong require continuous auditory feedback. The exact way in which this feedback is integrated into the vocal motor programs is not completely understood. Here we show that in sleeping zebra finches (Taeniopygia guttata), the activity of the song system selectively evoked by playbacks of their own song can be detected in the syrinx. Measuring the electrical activity of syringeal muscles, we found playback-evoked patterns identical to those recorded during song execution. Using this global and continuous readout we studied the activation dynamics of the song system elicited by different auditory stimuli. We found that a synthetic version of the bird’s song, rendered by a physical model of the avian phonation apparatus, evoked exactly the same response, albeit with lower efficiency. Analysis of these responses reveal a predictive and switch-like activation of the motor program, with preferred activation instants within the song.SignificanceThe study of the integration between sensory inputs and motor commands has greatly benefited from the finding that in sleeping oscine birds, playback of their own song evokes highly specific firing patterns in neurons also involved in the production of that song. Nevertheless, the sparse spiking patterns that can be recorded from few single neurons gives limited information of the overall activity of the song system. Here we show that this response is not limited to the central nervous system, but reaches vocal muscles. Combining this integrated measure of the activity of the system with surrogate synthetic songs, we found an all-or-nothing and predictive activation of the system, suggesting the existence of a pre-programmed internal dynamics.
Anomalous Scaling of Gene Expression in Confined Cell-Free Reactions
Authors: Sakamoto Ryota , Noireaux Vincent , Maeda Yusuke T. 
Published: January 2018

ABSTRACTCellular surface breaks the symmetry of molecular diffusion across membrane. Here, we study how steric interactions between the surface and the bulk of cell-sized emulsion droplets alters gene expression emulated by a cell-free transcription/translation (TXTL) system. The concentration of synthesized reporter proteins in droplets of radiusRshows an anomalous geometric scaling ofR4different from the expected normal size-dependence ofR3. Given that TXTL becomes less efficient at thin surface layer, a mathematical model explains anomalous size-dependence found in experiment. The surface of cell-sized compartment thus plays a regulatory role for cell-free gene expression.
Challenging the point neuron dogma: FS basket cells as 2-stage nonlinear integrators
Authors: Tzilivaki Alexandra , Kastellakis George , Poirazi Panayiota 
Published: January 2018

ABSTRACTInterneurons are critical for the proper functioning of neural circuits. While often morphologically complex, their dendrites have been ignored for decades, treating them as linear point neurons. Exciting new findings reveal complex, non-linear dendritic computations that call for a new theory of interneuron arithmetic. Using detailed biophysical models, we predict that dendrites of FS basket cells in both hippocampus and prefrontal cortex come in two flavors: supralinear, supporting local sodium spikes within large-volume branches and sublinear, in small-volume branches. Synaptic activation of varying sets of these dendrites leads to somatic firing variability that cannot be explained by the point neuron reduction. Instead, a 2-stage Artificial Neural Network (ANN), with sub- and supralinear hidden nodes, captures most of the variance. Reduced neuronal circuit modeling suggest that this bi-modal, 2-stage integration in FS basket cells confers substantial resource savings in memory encoding as well as the linking of memories across time.