bluuebunny/crossref_metadata_2025 huggingface dataset:
Mirrored continuum and molecular scale simulations of the ignition of high-pressure phases of RDX
Authors: Lee Kibaek , Joshi Kaushik , Chaudhuri Santanu , Stewart D. Scott
Published: May 2016

We present a mirrored atomistic and continuum framework that is used to describe the ignition of energetic materials, and a high-pressure phase of RDX in particular. The continuum formulation uses meaningful averages of thermodynamic properties obtained from the atomistic simulation and a simplification of enormously complex reaction kinetics. In particular, components are identified based on molecular weight bin averages and our methodology assumes that both the averaged atomistic and continuum simulations are represented on the same time and length scales. The atomistic simulations of thermally initiated ignition of RDX are performed using reactive molecular dynamics (RMD). The continuum model is based on multi-component thermodynamics and uses a kinetics scheme that describes observed chemical changes of the averaged atomistic simulations. Thus the mirrored continuum simulations mimic the rapid change in pressure, temperature, and average molecular weight of species in the reactive mixture. This mirroring enables a new technique to simplify the chemistry obtained from reactive MD simulations while retaining the observed features and spatial and temporal scales from both the RMD and continuum model. The primary benefit of this approach is a potentially powerful, but familiar way to interpret the atomistic simulations and understand the chemical events and reaction rates. The approach is quite general and thus can provide a way to model chemistry based on atomistic simulations and extend the reach of those simulations.
Heterogeneous and hyperfine interactions between valence states of molecular iodine correlating with the I(2P1/2) + I(2P1/2) dissociation limit
Authors: Baturo Vera V. , Cherepanov Igor N. , Lukashov Sergey S. , Poretsky Sergey A. , Pravilov Anatoly M. , Zhironkin Anatoly I.
Published: May 2016

Detailed analysis of interactions between all 0g+, 1u, and 0u− weakly bound states of iodine molecule correlating with the I(2P1/2) + I(2P1/2) (bb) dissociation limit has been performed. For this purpose, the 0u− (bb) state has been described using analysis of rotationally resolved excitation spectra of luminescence from the g0g− state populated in a three-step three-color perturbation facilitated excitation scheme via the 0u− state. Energies of 41 rovibrational levels, molecular constants, and potential energy curve have been determined. Energy gaps between closest rovibrational levels of the 0u− and 0g+, 1u (bb) states are found to be large, ∼6 cm−1. However, interaction of all three 0g+, 1u, and 0u− (bb) states has been observed. It has been found that the 0u− and 1u electronic states are mixed by heterogeneous interactions, while their mixing with the 0g+ one is due to hyperfine interactions predominantly. Admixture coefficients and electronic matrix elements of the coupling between the 0g+ ∼1u, 0g+∼0u−, and 0u− ∼1u states have been estimated.
Femtosecond stimulated Raman spectroscopy as a tool to detect molecular vibrations in ground and excited electronic states
Authors: Gelin Maxim F. , Domcke Wolfgang , Rao B. Jayachander
Published: May 2016

We give a detailed theoretical analysis of the simplest variant of femtosecond stimulated Raman spectroscopy, where a picosecond Raman pump pulse and a femtosecond Raman probe pulse are applied resonantly to a chromophore in thermal equilibrium in the ground electronic state. We demonstrate that this technique is capable of the detection of dephasing-free Raman-like lines revealing vibrational modes not only in the electronic ground state but also in the excited electronic state of the chromophore. The analytical results obtained with simplifying assumptions for the shape of the laser pulses are substantiated by numerical simulations with realistic laser pulses, employing the equation-of-motion phase-matching approach.
Quantitative velocity modulation spectroscopy
Authors: Hodges James N. , McCall Benjamin J.
Published: May 2016

Velocity Modulation Spectroscopy (VMS) is arguably the most important development in the 20th century for spectroscopic study of molecular ions. For decades, interpretation of VMS lineshapes has presented challenges due to the intrinsic covariance of fit parameters including velocity modulation amplitude, linewidth, and intensity. This limitation has stifled the growth of this technique into the quantitative realm. In this work, we show that subtle changes in the lineshape can be used to help address this complexity. This allows for determination of the linewidth, intensity relative to other transitions, velocity modulation amplitude, and electric field strength in the positive column of a glow discharge. Additionally, we explain the large homogeneous component of the linewidth that has been previously described. Using this component, the ion mobility can be determined.
Perspective: Role of structure prediction in materials discovery and design
Authors: Needs Richard J. , Pickard Chris J.
Published: May 2016

Materials informatics owes much to bioinformatics and the Materials Genome Initiative has been inspired by the Human Genome Project. But there is more to bioinformatics than genomes, and the same is true for materials informatics. Here we describe the rapidly expanding role of searching for structures of materials using first-principles electronic-structure methods. Structure searching has played an important part in unraveling structures of dense hydrogen and in identifying the record-high-temperature superconducting component in hydrogen sulfide at high pressures. We suggest that first-principles structure searching has already demonstrated its ability to determine structures of a wide range of materials and that it will play a central and increasing part in materials discovery and design.
Faster in-plane switching and reduced rotational viscosity characteristics in a graphene-nematic suspension
Authors: Basu Rajratan , Kinnamon Daniel , Skaggs Nicole , Womack James
Published: May 2016

The in-plane switching (IPS) for a nematic liquid crystal (LC) was found to be considerably faster when the LC was doped with dilute concentrations of monolayer graphene flakes. Additional studies revealed that the presence of graphene reduced the rotational viscosity of the LC, permitting the nematic director to respond quicker in IPS mode on turning the electric field on. The studies were carried out with several graphene concentrations in the LC, and the experimental results coherently suggest that there exists an optimal concentration of graphene, allowing a reduction in the IPS response time and rotational viscosity in the LC. Above this optimal graphene concentration, the rotational viscosity was found to increase, and consequently, the LC no longer switched faster in IPS mode. The presence of graphene suspension was also found to decrease the LC's pretilt angle significantly due to the π-π electron stacking between the LC molecules and graphene flakes. To understand the π-π stacking interaction, the anchoring mechanism of the LC on a CVD grown monolayer graphene film on copper substrate was studied by reflected crossed polarized microscopy. Optical microphotographs revealed that the LC alignment direction depended on monolayer graphene's hexagonal crystal structure and its orientation.
Influence of edge conditions on material ejection from periodic grooves in laser shock-loaded tin
Authors: de Rességuier T. , Roland C. , Prudhomme G. , Lescoute E. , Loison D. , Mercier P.
Published: May 2016

In a material subjected to high dynamic compression, the breakout of a shock wave at a rough free surface can lead to the ejection of high velocity debris. Anticipating the ballistic properties of such debris is a key safety issue in many applications involving shock loading, including pyrotechnics and inertial confinement fusion experiments. In this paper, we use laser driven shocks to investigate particle ejection from calibrated grooves of micrometric dimensions and approximately sinusoidal profile in tin samples, with various boundary conditions at the groove edges, including single groove and periodic patterns. Fast transverse shadowgraphy provides ejection velocities after shock breakout. They are found to depend not only on the groove depth and wavelength, as predicted theoretically and already observed in the past, but also, unexpectedly, on the edge conditions, with a jet tip velocity significantly lower in the case of a single groove than behind a periodic pattern.
Laser-generated shock wave attenuation aimed at microscale pyrotechnic device design
Authors: Yu Hyeonju , Yoh Jack J.
Published: May 2016

To meet the rising demand for miniaturizing the pyrotechnic device that consists of donor/acceptor pair separated by a bulkhead or a thin gap, the shock initiation sensitivity in the microscale gap test configuration is investigated. For understanding the shock attenuation within a gap sample (304 stainless steel) thickness of 10∼800 μm, the laser-generated shock wave in water confinement is adopted. The shock properties are obtained from the free surface velocity by making use of a velocity interferometer system for any reflector (VISAR). Analytical models for plasma generation in a confined geometry and for evolution and decay of shock waves during the propagation are considered. The shape and amplitude of the laser-driven initial pressure load and its attenuation pattern in the gap are effectively controlled for targeting the microscale propagation distance and subsequent triggering pressure for the acceptor charge. The reported results are important in the precise controlling of the shock strength during the laser initiation of microscale pyrotechnic devices.
Collection of low-grade waste heat for enhanced energy harvesting
Authors: Dede Ercan M. , Schmalenberg Paul , Wang Chi-Ming , Zhou Feng , Nomura Tsuyoshi
Published: May 2016

Enhanced energy harvesting through the collection of low-grade waste heat is experimentally demonstrated. A structural optimization technique is exploited in the design of a thermal-composite substrate to guide and gather the heat emanating from multiple sources to a predetermined location. A thermoelectric generator is then applied at the selected focusing region to convert the resulting low-grade waste heat to electrical power. The thermal characteristics of the device are experimentally verified by direct temperature measurements of the system and numerically validated via heat conduction simulations. Electrical performance under natural and forced convection is measured, and in both cases, the device with optimized heat flow control plus energy harvesting demonstrates increased power generation when compared with a baseline waste heat recovery system. Electronics applications include energy scavenging for autonomously powered sensor networks or self-actuated devices.
Understanding change in the ecological character of Ramsar wetlands: perspectives from a deeper time – synthesis
Authors: Gell P. A. , Finlayson C. M. , Davidson N. C.
Published: May 2016

The Convention for Wetlands was signed in 1971 as part of a global measure to mitigate the loss and degradation of the world’s wetlands. Signatory nations nominate wetlands as internationally important and commit to maintaining their ‘ecological character’. In many cases the character that has been maintained was that occurring at the time of nomination with scant attention to the variability and change that occurs over longer periods. Palaeoclimate and palaeoecological research now reveals a diverse array of conditions in wetlands in the past and attests that any recently identified condition may be transient. The research further reveals the considerable magnitude and antiquity of the impact of people on wetlands. Hence the site description used by wetland managers would benefit from the provision of a longer-term perspective of change. The changing state of wetlands provides a dilemma for wetland managers. In response, a workshop on understanding change in wetlands was held in Queenscliff, Australia, in November 2013 to draw together perspectives of change from neo- and palaeoecological sources to enable the formulation of new pathways of assessment to better accommodate the dynamic nature of wetlands. A synthesis of the information provided at the workshop is provided in this paper.
Selectivity and tolerance for visual texture in macaque V2
Authors: Ziemba Corey M. , Freeman Jeremy , Movshon J. Anthony , Simoncelli Eero P.
Published: May 2016

Significance

The brain generates increasingly complex representations of the visual world to recognize objects, to form new memories, and to organize visual behavior. Relatively simple signals in the retina are transformed through a cascade of neural computations into highly complex responses in visual cortical areas deep in the temporal lobe. The representations of visual signals in areas that lie in the middle of this cascade remain poorly understood, yet they are critical to understanding how the cascade operates. Here, we demonstrate changes in the representation of visual information from area V1 to V2, and show how these changes extract and represent information about the local statistical features of visual images.
“Forward to David the Builder!” Georgia's (re)turn to language-centered nationalism
Authors: Berglund Christofer
Published: May 2016

After the Rose Revolution, President Saakashvili tried to move away from the exclusionary nationalism of the past, which had poisoned relations between Georgians and their Armenian and Azerbaijani compatriots. His government instead sought to foster an inclusionary nationalism, wherein belonging was contingent upon speaking the state language and all Georgian speakers, irrespective of origin, were to be equals. This article examines this nation-building project from a top-down and bottom-up lens. I first argue that state officials took rigorous steps to signal that Georgian-speaking minorities were part of the national fabric, but failed to abolish religious and historical barriers to their inclusion. I next utilize a large-scale, matched-guise experiment (n= 792) to explore if adolescent Georgians ostracize Georgian-speaking minorities or embrace them as their peers. I find that the upcoming generation of Georgians harbor attitudes in line with Saakashvili's language-centered nationalism, and that current Georgian nationalism therefore is more inclusionary than previous research, or Georgia's tumultuous past, would lead us to believe.
Large‐scale curriculum reform in Finland – exploring the interrelation between implementation strategy, the function of the reform, and curriculum coherence
Authors: Pietarinen Janne , Pyhältö Kirsi , Soini Tiina
Published: May 2016

The study aims to gain a better understanding of the national large‐scale curriculum process in terms of the used implementation strategies, the function of the reform, and the curriculum coherence perceived by the stakeholders accountable in constructing the national core curriculum in Finland. A large body of school reform literature has shown that a central determinant for the effectiveness of curriculum reform is the way in which the reform is implemented. Accordingly, implementing curriculum reform always entails translation of the new ideas into new educational practices, which involves complex sense‐making processes from those involved. Altogether, 117 stakeholders accountable in constructing the national core curriculum in Finland completed a survey. The results showed that the effect of the implementation strategy for the perceived curriculum coherence was mediated by the perceived educational impact of the reform both for the school and society. The mediated interrelation between the top‐down–bottom‐up implementation strategy in the curriculum process, and the estimated coherence in the written core curriculum implies that the objects of the activities, namely elaborating and focusing on the educational impact of the decisions, is a crucial determinant for achieving curriculum coherence, and further, facilitating sustainable school development at the local level.
Novel predator recognition by Allenby's gerbil (Gerbillus andersoni allenbyi): do gerbils learn to respond to a snake that can “see” in the dark?
Authors: Bleicher Sonny S. , Brown Joel S. , Embar Keren , Kotler Burt P.
Published: May 2016

Unlike desert rodents from North America, Allenby's gerbil (Gerbillus andersoni allenbyi) from the Negev Desert, Israel has evolved with snakes that do not have heat-sensitive sensory pits that enhance night vision. Does this history affect their ability to assess and respond to a snake that has this ability? As a test, we exposed gerbils to risk of predation from various predators, including snakes, owls, and foxes. The snakes included the Saharan horned viper (Cerastes cerastes) and the sidewinder rattlesnake (Crotalus cerastes). The former snake lacks sensory pits and shares a common evolutionary history with the gerbil. The latter snake, while convergent evolutionarily on the horned viper, has sensory pits and no prior history with the gerbil. The gerbils exploited depletable resource patches similarly, regardless of snake species and moon phase. While the gerbils did not respond to the novel snake as a greater threat than their familiar horned viper, the gerbils were cognizant that the novel predator was a threat. In response to both snakes, giving-up densities (GUDs; the amount of food left in a resource patch following exploitation) of the gerbils were higher in the bush than open microhabitat. In response to moonlight, GUDs were higher on full than on the new moon. Based on GUDs, the gerbils responded most to the risk of predation from the red fox, least from the two snake species, and intermediate for the barn owl.
Individual differences in working memory capacity and resistance to belief bias in syllogistic reasoning
Authors: Robison Matthew K. , Unsworth Nash
Published: May 2016

In two experiments, we investigated the possibility that individual differences in working memory capacity (WMC) would provide resistance to belief bias in syllogistic reasoning. In Experiment 1 ( N = 157), participants showed a belief bias effect in that they had longer response times and decreased accuracy on syllogisms with conflict between the validity and believability of the conclusion than on syllogisms with no such conflict. However, this effect did not differ as a function of individual differences in WMC. Experiment 2 ( N = 122) replicated this effect with the addition of decontextualized (i.e., nonsense) syllogisms as a different means of measuring the magnitude of the belief bias effect. Although individual differences in WMC and fluid intelligence were related to better reasoning overall, the magnitude of the belief bias effect was not smaller for participants with greater WMC. The present study offers two novel findings: (a) The belief bias effect is independent of individual differences in WMC and fluid intelligence, and (b) resolving conflict in verbal reasoning is not a type of conflict resolution that correlates with individual differences in WMC, further establishing boundary conditions for the role of WMC in human cognitive processes.
Food for thought: pretty good multispecies yield
Authors: Rindorf Anna , Dichmont Catherine Mary , Levin Phillip S. , Mace Pamela , Pascoe Sean , Prellezo Raul , Punt André E. , Reid David G. , Stephenson Robert , Ulrich Clara , Vinther Morten , Clausen Lotte Worsøe
Published: May 2016

MSY principles for marine fisheries management reflect a focus on obtaining continued high catches to provide food and livelihoods for humanity, while not compromising ecosystems. However, maintaining healthy stocks to provide the maximum sustainable yield on a single-species basis does not ensure that broader ecosystem, economic, and social objectives are addressed. We investigate how the principles of a “pretty good yield” range of fishing mortalities assumed to provide >95% of the average yield for a single stock can be expanded to a pretty good multispecies yield (PGMY) space and further to pretty good multidimensional yield to accommodate situations where the yield from a stock affects the ecosystem, economic and social benefits, or sustainability. We demonstrate in a European example that PGMY is a practical concept. As PGMY provides a safe operating space for management that adheres to the principles of MSY, it allows the consideration of other aspects to be included in operational management advice in both data-rich and data-limited situations. PGMY furthermore provides a way to integrate advice across stocks, avoiding clearly infeasible management combinations, and thereby hopefully increasing confidence in scientific advice.
Implementation of Xpert MTB/RIF in Uganda: Missed Opportunities to Improve Diagnosis of Tuberculosis
Authors: Hanrahan Colleen F. , Haguma Priscilla , Ochom Emmanuel , Kinera Irene , Cobelens Frank , Cattamanchi Adithya , Davis Luke , Katamba Achilles , Dowdy David
Published: May 2016

Background.  The effect of Xpert MTB/RIF (Xpert) scale-up on patient outcomes in low-income settings with a high tuberculosis (TB) burden has not been established. We sought to characterize the effectiveness of Xpert as implemented across different levels of the healthcare system in Uganda.

Methods.  We reviewed laboratory records from 2012 to 2014 at 18 health facilities throughout Uganda. In 8 facilities, Xpert had been implemented onsite since 2012, and in 10 sites Xpert was available as an offsite referral test from another facility. We describe Xpert testing volumes by facility, Xpert and smear microscopy results, and downtime due to malfunction and cartridge stockouts. We compare TB treatment initiation as well as time to treatment between facilities implementing Xpert and those that did not.

Results.  The median number of Xpert assays run at implementing facilities was 25/month (interquartile range [IQR], 10–63), amounting to 8% of total capacity. Among 1251 assays run for a new TB diagnosis, 19% were positive. Among 1899 patients with smear-negative presumptive TB, the proportion starting TB treatment was similar between Xpert facilities (11%; 95% confidence interval [CI], 9%–13%) and non-Xpert facilities (9%; 95% CI, 8%–11%; P = .325). In Xpert facilities, a positive Xpert preceded TB treatment initiation in only 12 of 70 (17%) smear-negative patients initiated on treatment.

Conclusions.  Xpert was underutilized in Uganda and did not significantly increase the number of patients starting treatment for TB. Greater attention must be paid to appropriate implementation of novel diagnostic tests for TB if these new tools are to impact patient important outcomes.
First Case of Lyme Arthritis Involving a Prosthetic Knee Joint
Authors: Wright William F. , Oliverio James A.
Published: May 2016

Borrelia burgdorferi sensu stricto is the most common tick-borne illness in the United States. Arthritis is usually a mani­festation of late dis­ease but has not been associated with cases of periprosthetic joint infections. We report on a patient who was first diagnosed with periprosthetic joint infection and subsequently Lyme arthritis.
Human Immunodeficiency Virus as a Chronic Disease: Evaluation and Management of Nonacquired Immune Deficiency Syndrome-Defining Conditions
Authors: Serrano-Villar Sergio , Gutiérrez Félix , Miralles Celia , Berenguer Juan , Rivero Antonio , Martínez Esteban , Moreno Santiago
Published: May 2016

In the modern antiretroviral therapy (ART) era, motivated people living with human immunodeficiency virus (HIV) who have access to therapy are expected to maintain viral suppression indefinitely and to receive treatment for decades. Hence, the current clinical scenario has dramatically shifted since the early 1980s, from treatment and prevention of opportunistic infections and palliative care to a new scenario in which most HIV specialists focus on HIV primary care, ie, the follow up of stable patients, surveillance of long-term toxicities, and screening and prevention of age-related conditions. The median age of HIV-infected adults on ART is progressively increasing. By 2030, 3 of every 4 patients are expected to be aged 50 years or older in many countries, more than 80% will have at least 1 age-related disease, and approximately one third will have at least 3 age-related diseases. Contemporary care of HIV-infected patients is evolving, and questions about how we might monitor and perhaps even treat HIV-infected adults have emerged. Through key published works, this review briefly describes the most prevalent comorbidities and age-associated conditions and highlights the differential features in the HIV-infected population. We also discuss the most critical aspects to be considered in the care of patients with HIV for the management and prevention of age-associated disease.
Systemic QX-314 Reduces Bone Cancer Pain through Selective Inhibition of Transient Receptor Potential Vanilloid Subfamily 1–expressing Primary Afferents in Mice
Authors: Fuseya Satoshi , Yamamoto Katsumi , Minemura Hitoshi , Yamaori Satoshi , Kawamata Tomoyuki , Kawamata Mikito
Published: May 2016

AbstractAbstract

In mice with behavioral evidence of pain and dysfunction after injection of cancer cells in bone, systemic QX-314, but not lidocaine, produced a long-lasting reduction in spontaneous flinching behavior by inhibiting transient receptor potential vanilloid subfamily 1–expressing nerves, but did not reduce activity-dependent disruption of behaviors.

Supplemental Digital Content is available in the text.

Background

The aim of this study was to determine whether systemic administration of QX-314 reduces bone cancer pain through selective inhibition of transient receptor potential vanilloid subfamily 1 (TRPV1)–expressing afferents.

Methods

A mouse model of bone cancer pain was used. The authors examined the effects of bolus (0.01 to 3 mg/kg, n = 6 to 10) and continuous (5 mg kg−1 h−1, n = 5) administration of QX-314 on both bone cancer pain–related behaviors and phosphorylated cyclic adenosine monophosphate response element–binding protein expression in dorsal root ganglion neurons (n = 3 or 6) and the effects of ablation of TRPV1-expressing afferents on bone cancer pain–related behaviors (n = 10).

Results

The numbers of flinches indicative of ongoing pain in QX-314–treated mice were smaller than those in vehicle-treated mice at 10 min (3 mg/kg, 4 ± 3; 1 mg/kg, 5 ± 3 vs. 12 ± 3; P < 0.001; n = 8 to 9), 24 h (3 ± 2 vs. 13 ± 3, P < 0.001), and 48 h (4 ± 1 vs. 12 ± 2, P < 0.001; n = 5 in each group) after QX-314 administration, but impaired limb use, weight-bearing including that examined by the CatWalk system, and rotarod performance indicative of movement-evoked pain were comparable. QX-314 selectively inhibited the increase in phosphorylated cyclic adenosine monophosphate response element–binding protein expression in TRPV1-positive, but not in TRPV1-negative, dorsal root ganglion neurons compared to that in the case of vehicle administration (32.2 ± 3.0% vs. 52.6 ± 5.9%, P < 0.001; n = 6 in each group). Ablation of TRPV1-expressing afferents mimicked the effects of QX-314.

Conclusion

This study showed that systemic administration of QX-314 in mice inhibits some behavioral aspects of bone cancer pain through selective inhibition of TRPV1-expressing afferents without coadministration of TRPV1 agonists.
Cutaneous Mitochondrial Po 2, but Not Tissue Oxygen Saturation, Is an Early Indicator of the Physiologic Limit of Hemodilution in the Pig
Authors: Römers Luuk H. L. , Bakker Charlotte , Dollée Nathalie , Hoeks Sanne E. , Lima Alexandre , Raat Nicolaas J. H. , Johannes Tanja , Stolker Robert J. , Mik Egbert G.
Published: May 2016

AbstractAbstract

The authors have developed a sophisticated technology to measure cutaneous mitochondrial oxygen tension, and hereby investigate the influence of hemodilution on the measurements in a porcine model. The authors show that the measurement of cutaneous mitochondrial oxygen tension is feasible and that it may be a promising physiologic trigger to guide transfusion therapy and patient management.

Background

Hemodilution is a consequence of fluid replacement during blood loss and is limited by the individual ability to compensate for decreasing hemoglobin level. We tested the ability of a novel noninvasive method for measuring cutaneous mitochondrial Po
2 (mitoPo
2) to detect this threshold early.

Methods

Anesthetized and ventilated pigs were hemodynamically monitored and randomized into a hemodilution (n = 12) or a time control (TC) group (n = 14). MitoPo
2 measurements were done by oxygen-dependent delayed fluorescence of protoporphyrin IX after preparation of the skin with 20% 5-aminolevulinic acid cream. Tissue oxygen saturation (StO2) was measured with near infrared spectroscopy on the thoracic wall. After baseline measurements, progressive normovolemic hemodilution was performed in the hemodilution group in equal steps (500 ml blood replaced by 500 ml Voluven®; Fresenius Kabi AG, Germany). Consecutive measurements were performed after 20-min stabilization periods and repeated 8 times or until the animal died.

Results

The TC animals remained stable with regard to hemodynamics and mitoPo
2. In the hemodilution group, mitoPo
2 became hemoglobin-dependent after reaching a threshold of 2.6 ± 0.2 g/dl. During hemodilution, hemoglobin and mitoPo
2 decreased (7.9 ± 0.2 to 2.1 ± 0.2 g/dl; 23.6 ± 2 to 9.9 ± 0.8 mmHg), but StO2 did not. Notably, mitoPo
2 dropped quite abruptly (about 39%) at the individual threshold. We observed that this decrease in mitoPo
2 occurred at least one hemodilution step before changes in other conventional parameters.

Conclusions

Cutaneous mitoPo
2 decreased typically one hemodilution step before occurrence of significant alterations in systemic oxygen consumption and lactate levels. This makes mitoPo
2 a potential early indicator of the physiologic limit of hemodilution and possibly a physiologic trigger for blood transfusion.
Concurrent Meniscal and Chondral Injuries in Pediatric and Adolescent Patients Undergoing ACL Reconstruction
Authors: Vavken Patrick , Tepolt Frances A. , Kocher Mininder S.
Published: May 2016

Background/Purpose:

The aim of this study is to assess the prevalence of and risk factors for concurrent meniscal and articular cartilage injury in children and adolescents undergoing anterior cruciate ligament (ACL) reconstruction.

Methods:

Medical records of pediatric patients (below 18 y old) undergoing ACL surgery during the 2013 to 2014 academic year at a tertiary care children’s hospital were reviewed for clinical or radiographic documentation of meniscal or chondral injury. Prevalence of concurrent injury was regressed on the basis of age, sex, body mass index (BMI), and time between injury and surgery. Skeletally immature patients were analyzed as a separate subgroup.

Results:

Medical records of 208 patients with a mean age of 15±2 years were reviewed. Overall, 117 patients (56%) were found to have had at least 1 concurrent injury; 66 patients (32%) had a medial meniscus tear, 72 patients (35%) had a lateral meniscus tear, and 10 patients (5%) had a chondral lesion. Both BMI and time duration between injury and ACL reconstruction surgery were significant predictors for meniscal or chondral injury, with increase in injury prevalence of approximately 10% per point BMI and 6% per month delay to surgery.

Conclusions:

More than half of the children and the adolescents treated for ACL tear have concurrent meniscal or chondral injury. Risk factors for concurrent injury are BMI and time duration between injury and surgery. The prevalence of concurrent injury and associated risk factors should be considered when counseling a pediatric patient and family regarding operative versus nonoperative management in the setting of an ACL tear.

Level of Evidence:

Level IV—case series.
SPONTANEOUS BILATERAL HEMORRHAGIC CHOROIDAL DETACHMENTS ASSOCIATED WITH MALIGNANT HYPERTENSION
Authors: Cheung Albert Y. , David James A. , Ober Michael D.
Published: May 2016

Purpose:

To report the details of a patient with bilateral spontaneous suprachoroidal hemorrhages related to malignant hypertension.

Methods:

Observational case report with review of relevant literature.

Results:

A 62-year-old man with a history of hypertension was referred secondary to bilateral temporal scotomas and persistent headache for 3 days. Symptoms began during an inpatient admission for malignant hypertension. Examination revealed bilateral 360° hemorrhagic choroidal detachments without retinal hemorrhage or detachment. Choroidal hemorrhages underwent prompt resolution with blood pressure control.

Conclusion:

Spontaneous suprachoroidal hemorrhage is a rare event and should prompt a focused systemic workup including the evaluation of blood pressure.
Idarucizumab for Reversing Dabigatran-Induced Anticoagulation: A Systematic Review
Authors: Thibault Nathan , Morrill Amanda M. , Willett Kristine C.
Published: May 2016

Background:

The approval of the oral direct thrombin inhibitor, dabigatran etexilate, gave patients an alternative to oral anticoagulation with warfarin. Like all anticoagulants, the primary adverse event (AE) associated with dabigatran is bleeding. Until the FDA approval of idarucizumab, there had been no reversal agent for dabigatran-induced anticoagulation in patients with life-threatening or uncontrollable bleeding, or those requiring emergent procedures.

Areas of Uncertainty:

The primary purpose of this review is to summarize the safety and efficacy of idarucizumab, a monoclonal antibody fragment, and its use as a reversal agent for dabigatran.

Data Sources:

A literature search was conducted through MEDLINE (1946 to November week 1 2015) and Embase (1980–2015 week 46) using the search term idarucizumab. Clinicaltrials.gov was consulted for a comprehensive list of ongoing and completed studies. Additional studies were identified through bibliographical citations. Clinical trials in animals and humans published in English evaluating the safety and efficacy of idarucizumab for reversal of anticoagulant treatment with dabigatran were included for review.

Results:

Idarucizumab has been shown to significantly reverse the anticoagulant effects of dabigatran in both healthy volunteers and patients requiring a reversal agent because of either overt bleeding or an emergency surgery or invasive procedure. The most common AEs were headache, nasopharyngitis, back pain, skin irritation, hypokalemia, delirium, constipation, pyrexia, and pneumonia. Deaths reported in idarucizumab studies were attributed to either the index event or a preexisting comorbidity. Most adverse effects were minor, but 21 serious AEs have been reported in the published data including thrombotic events.

Conclusions:

Given the increased use of direct oral anticoagulants, such as dabigatran, a need for specific reversal agents exists. Idarucizumab has been shown to be safe and effective in the reversal of dabigatran-induced anticoagulation in patients requiring emergent or urgent surgery or in patients with severe bleeding.
Treatment of Metastatic, Refractory Alveolar Soft Part Sarcoma: Case Reports and Literature Review of Treatment Options in the Era of Targeted Therapy
Authors: Kuo Dennis J. , Menell Jill S. , Glade Bender Julia L.
Published: May 2016

Background:

Alveolar soft part sarcoma is a rare soft tissue sarcoma that is characterized by a pattern of slow growth with metastases to the lung, bone, and brain that is not responsive to conventional cytotoxic chemotherapy.

Observations:

We describe 2 patients, with a combined 19 years of treatment experience including multiple different chemotherapeutic and targeted therapy regimens, surgery, and radiotherapy. We also present a review of the literature regarding treatment options to highlight recent findings.

Conclusions:

Alveolar soft part sarcoma is an indolent, but persistently progressive disease. Novel therapeutic agents hold promise in its management.
Prevalence of Endocrinopathies in Turkish Children With β-Thalassemia Major: A Single-Center Study
Authors: Altincik Ayça , Akin Mehmet
Published: May 2016

Present chelation protocols have increased the life quality and survival of the patients with β-thalassemia major (BTM). However, endocrine complications are still mostly experienced. The aim of this study was to determine the prevalence of endocrine complications in children with BTM, and to study the relationship between serum ferritin levels and complications. Forty-five children (female: 23/male: 22, mean age: 12.39±3.72 y) with BTM were enrolled into the study. Blood samples were taken after an overnight fasting, early in the morning from entire study group. Median (range) serum ferritin of the patients was 1365 ng/mL (362 to 5996 ng/mL). The most prevalent endocrine complications were vitamin D insufficiency (54.5%), short stature (42%), pubertal impairment (25% for each sex), and osteopenia (13%), respectively. Ferritin levels were not correlated with anthropometric or laboratory data. Monitoring of growth, vitamin D status, and endocrine functions are essential to achieve a good quality of life in BTM patients.
Results of Therapy for Wilms Tumor and Other Malignant Kidney Tumors: A Report From the Chilean Pediatric National Cancer Program (PINDA)
Authors: Joannon Pilar , Becker Ana , Kabalan Paola , Concha Emma , Beresi Victoria , Salgado Carmen , Martínez Pilar , Olate Paola , Arriagada Mónica , Espinoza Felipe , Varas Mónica , Benavides Pablo , Valero Miguel , Reyes Mauricio
Published: May 2016

Objective:

The aim of this study was to analyze the survival of children with Wilms tumor and other malignant renal tumors treated with the TWPINDA-99 protocol.

Materials and Methods:

Between January 1999 and December 2013, 226 patients were registered on this trial, based on National Wilms Tumor Study-5. Patient characteristics and survival were evaluated.

Results:

Two hundred seven patients were diagnosed with Wilms tumor, which represented 91.6% of renal tumors. The male to female ratio was 0.7:1. The median age at diagnosis was 3.3 years. Stage III was the most frequent (39.2%). Metastatic disease was present in 16.7% of the cases. Synchronous bilateral disease was observed in 9.3% of the cases. Favorable histology was diagnosed in 93.6% and anaplastic histology in 6.4% of the patients. Median follow-up was 7.5 years. Ten-year event-free survival and overall survival (OS) for assessable patients with Wilms tumor (n=192) were 82.0% and 89.9%, respectively. OS for patients with stage I was 100% (n=36), stage II: 97.1% (n=35), stage III: 88.6% (n=71), stage IV: 77.9% (n=32), and stage V: 80.8% (n=18). OS for favorable histology (n=180) and anaplastic histology tumors (n=12) were 91.0% and 72.9%, respectively. Other malignant renal tumors had a poorer survival.

Conclusion:

Prognosis for patients with Wilms tumor treated on TWPINDA-99 seems to be better than previous national trials and is similar to developed countries.
Phase I and Phase II Objective Response Rates are Correlated in Pediatric Cancer Trials: An Argument for Better Clinical Trial Efficiency
Authors: Yeh Jonathan C. , Huang Peng , Cohen Kenneth J.
Published: May 2016

Although many phase I trials report tumor response, formal analysis of efficacy is deferred to phase II. We reviewed paired phase I and II pediatric oncology trials to ascertain the relationship between phase I and II objective response rate (OR%). Single-agent phase I trials were paired with corresponding phase II trials (comparable study drug, dosing schedule, and population). Phase I trials without efficacy data or a matching phase II trial were excluded. OR% was tabulated for all trials, and phase II authors’ subjective conclusions regarding efficacy were documented; 35 pairs of trials were analyzed. The correlation between phase I and II OR% was 0.93. Between phase II studies with a “positive” conclusion versus a “negative” one, there was a statistically significant difference in mean phase I OR% (32.0% vs. 4.5%, P<0.001). Thirteen phase II studies were undertaken despite phase I OR% of 0%; only 1 had a “positive” conclusion, and none exceeded OR% of 15%. OR% are highly correlated between phase I and II pediatric oncology trials. Although not a formal measure of drug efficacy, phase I OR% may provide an estimate of phase II response, inform phase II study design, and should be given greater consideration.
Safety and Effectiveness of Intravenous Pentamidine for Prophylaxis of Pneumocystis jirovecii Pneumonia in Pediatric Hematology/Oncology Patients
Authors: Solodokin Loriel J. , Klejmont Liana M. , Scipione Marco R. , Dubrovskaya Yanina , Lighter-Fisher Jennifer , Papadopoulos John
Published: May 2016

Background:

Pneumocystis jirovecii pneumonia (PCP) is an opportunistic infection that can lead to significant morbidity and mortality in immunocompromised pediatric hematology/oncology patients. Trimethoprim/sulfamethoxazole is the gold standard for prophylaxis. Intravenous (IV) pentamidine is the preferred second-line agent for PCP prophylaxis at our institution and is used first-line under certain circumstances. The purpose of this study is to evaluate the effectiveness and safety of IV pentamidine for PCP prophylaxis in pediatric hematology/oncology patients.

Materials and Methods:

A retrospective analysis of pediatric hematology/oncology patients (N=121) who received ≥1 dose of IV pentamidine between January 2009 and July 2014 was conducted. Electronic health records were reviewed to determine baseline characteristics, rate of breakthrough PCP infection, characteristics of IV pentamidine use, and adverse events. The follow-up period was 6 months after the last reported IV pentamidine dose or the last recorded clinic visit/hospital admission.

Results:

No patients developed PCP during the entirety of their IV pentamidine course or during the follow-up period. Nineteen patients (16%) experienced adverse events and 5 of the 19 patients required discontinuation of IV pentamidine.

Conclusions:

IV pentamidine is a safe, tolerable, and effective agent for PCP prophylaxis in pediatric hematology/oncology patients and may be considered a reasonable therapeutic alternative when trimethoprim/sulfamethoxazole cannot be used for PCP prophylaxis.
Assessment of Body Composition in a Group of Pediatric Patients With Cancer: A Single Romanian Center Experience
Authors: Chinceşan Mihaela Ioana , Mărginean Cristina Oana , Voidăzan Septimiu
Published: May 2016

Cancer patients are particularly susceptible to nutritional depletion. From March 2014 to December 2015, we assessed 146 patients consecutively hospitalized in a tertiary emergency pediatric hospital. The patients were divided into 2 groups: group I, patients with cancer (43 patients), and group II, the control group consisting of 103 age-matched and sex-matched healthy patients. The anthropometric parameters (weight-W, height-H, body mass index [BMI], middle upper arm circumference [MUAC], tricipital skinfold thickness [TST]) and biochemical parameters (proteins, albumin) were comparatively evaluated. Fat mass (FM, kg and %), fat-free mass (FFM, kg), muscle mass (MM, kg), and total body water (TBW, %) were measured in both groups using Tanita BC 420 S MA Analyzer. Anthropometric and biochemical parameters in group I were significantly different from those in group II for weight, height, BMI, MUAC, TST, protein, and albumin (P<0.05). In the study group, FM was much lower compared with controls 16.9% (3.4% to 33.3%) versus 20.3% (6.6% to 38.4%); (P=0.001), and TBW was much higher 60.8% (48.8% to 70.6%) versus 58.5% (45.2% to 68.6%) (P=0.004). FFM and MM were not statistically different in the 2 groups. The results highlight the complex changes of nutritional status in pediatric patients with cancer.
Effects of Race/Ethnicity and Socioeconomic Status on Outcome in Childhood Acute Lymphoblastic Leukemia
Authors: Acharya Sahaja , Hsieh Samantha , Shinohara Eric T. , DeWees Todd , Frangoul Haydar , Perkins Stephanie M.
Published: May 2016

With modern therapy, overall survival (OS) for children with acute lymphoblastic leukemia approaches 90%. However, inferior outcomes for minority children have been reported. Data on the effects of ethnicity/race as it relates to socioeconomic status are limited. Using state cancer registry data from Texas and Florida, we evaluated the impact of neighborhood-level poverty rate and race/ethnicity on OS for 4719 children with acute lymphoblastic leukemia. On multivariable analysis, patients residing in neighborhoods with the highest poverty rate had a 1.8-fold increase in mortality compared with patients residing in neighborhoods with the lowest poverty rate (hazard ratio [HR], 1.8; 95% confidence interval [CI], 1.41-2.30). Hispanic and non-Hispanic black patients also had increased risk of mortality compared with non-Hispanic white patients (Hispanic: HR, 1.18; 95% CI, 1.01-1.39; non-Hispanic black: HR, 1.31; 95% CI, 1.03-1.66). On subgroup analysis, there was a 21.7% difference in 5-year OS when comparing non-Hispanic white children living in the lowest poverty neighborhoods (5-year OS, 91.2%; 95% CI, 88.6-93.2) to non-Hispanic black children living in the highest poverty neighborhoods (5-year OS, 69.5%; 95% CI, 61.5-76.1). To address such disparities in survival, further work is needed to identify barriers to cancer care in this pediatric population.
Improving Communication During Cardiac ICU Multidisciplinary Rounds Through Visual Display of Patient Daily Goals*
Authors: Justice Lindsey B. , Cooper David S. , Henderson Carla , Brown James , Simon Katherine , Clark Lindsey , Fleckenstein Elizabeth , Benscoter Alexis , Nelson David P.
Published: May 2016

Objectives:

To improve communication during daily cardiac ICU multidisciplinary rounds.

Design:

Quality improvement methodology.

Setting:

Twenty-five–bed cardiac ICUs in an academic free-standing pediatric hospital.

Patients:

All patients admitted to the cardiac ICU.

Interventions:

Implementation of visual display of patient daily goals through a write-down and read-back process.

Measurements and Main Results:

The Rounds Effectiveness Assessment and Communication Tool was developed based on the previously validated Patient Knowledge Assessment Tool to evaluate comprehension of patient daily goals. Rounds were assessed for each patient by the bedside nurse, nurse practitioner or fellow, and attending physician, and answers were compared to determine percent agreement per day. At baseline, percent agreement for patient goals was only 62%. After initial implementation of the daily goal write-down/read-back process, which was written on paper by the bedside nurse, the Rounds Effectiveness Assessment and Communication Tool survey revealed no improvement. With adaptation of the intervention so goals were written on whiteboards for visual display during rounds, the percent agreement improved to 85%. Families were also asked to complete a survey (1–6 Likert scale) of their satisfaction with rounds and understanding of daily goals before and after the intervention. Family survey results improved from a mean of 4.6–5.7. Parent selection of the best possible score for each question was 19% at baseline and 75% after the intervention.

Conclusions:

Visual display of patient daily goals via a write-down/read-back process improves comprehension of goals by all team members and improves parent satisfaction. The daily goal whiteboard facilitates consistent development of a comprehensive plan of care for each patient, fosters goal-directed care, and provides a checklist for providers and parents to review throughout the day.