bluuebunny/crossref_metadata_2025 huggingface dataset:
Limited Mantle Hydration by Bending Faults at the Middle America Trench
Authors: Miller Nathaniel C. , Lizarralde Daniel , Collins John A. , Holbrook W. Steven , Van Avendonk Harm J. A.
Published: December 2020

Seismic anisotropy measurements show that upper mantle hydration at the Middle America Trench (MAT) is limited to serpentinization and/or water in fault zones, rather than distributed uniformly. Subduction of hydrated oceanic lithosphere recycles water back into the deep mantle, drives arc volcanism, and affects seismicity at subduction zones. Constraining the extent of upper mantle hydration is an important part of understanding many fundamental processes on Earth. Substantially reduced seismic velocities in tomography suggest that outer rise plate‐bending faults provide a pathway for seawater to rehydrate the slab mantle just prior to subduction. Estimates of outer‐rise hydration based on tomograms vary significantly, with some large enough to imply that, globally, subduction has consumed more than two oceans worth of water during the Phanerozoic. We found that, while the mean upper mantle wavespeed is reduced at the MAT outer rise, the amplitude and orientation of inherited anisotropy are preserved at depths >1 km below the Moho. At shallower depths, relict anisotropy is replaced by slowing in the fault‐normal direction. These observations are incompatible with pervasive hydration but consistent with models of wave propagation through serpentinized fault zones that thin to <100‐m in width at depths >1 km below Moho. Confining hydration to fault zones reduces water storage estimates for the MAT upper mantle from ∼3.5 wt% to <0.9 wt% H20. Since the intermediate thermal structure in the ∼24 Myr‐old MAT slab favors serpentinization, limited hydration suggests that fault mechanics are the limiting factor, not temperatures. Subducting mantle may be similarly dry globally.
Eastward Dipping Style of the Underthrusting Indian Lithosphere Beneath the Tethyan Himalaya Illuminated by P and S Receiver Functions
Authors: Xu Qiang , Liu Hongbing , Yuan Xiaohui , Zhao Junmeng , Pei Shunping
Published: December 2020

To explore the west‐east variations in the underthrusting Indian lithosphere, we investigate the lithospheric structure using P and S receiver functions obtained from a west‐east linear array of 19 broadband stations spanning the Tethyan Himalaya at 85.5–88.5°E. Our observations of the Main Himalayan Thrust (MHT) and Moho serving as the top and bottom boundaries at depths of 42–54 km and 60–72 km, respectively, suggest that a thinning Indian lower crust with an eastward inclined geometry is underthrusting beneath the Tethyan Himalaya. An intra‐crustal low velocity zone (LVZ) immediately above the MTH at depths of 32–42 km is imaged, likely resulting from the presence of crustal dehydration partial melting. We propose that this LVZ induces the southward extrusion of melt‐weakened crustal material with itself as a channel and facilitates the development of duplexing structures, by which Indian lower crustal materials could be accreted into the Himalayan wedge along the north‐south mid‐crustal ramp in the MHT. The eastward dipping lithosphere‐asthenosphere boundary is clearly observed ranging from 90 to 126 km, which generally coincides with the changing trends of the MHT and Moho. These observations can be attributed to the eastward steepening subduction angle of the Indian lithosphere.
Complex Basal Conditions and Their Influence on Ice Flow at the Onset of the Northeast Greenland Ice Stream
Authors: Franke Steven , Jansen Daniela , Beyer Sebastian , Neckel Niklas , Binder Tobias , Paden John , Eisen Olaf
Published: December 2020

The ice stream geometry and large ice surface velocities at the onset region of the Northeast Greenland Ice Stream (NEGIS) are not yet well reproduced by ice sheet models. The quantification of basal sliding and a parametrization of basal conditions remains a major gap. In this study, we assess the basal conditions of the onset region of the NEGIS in a systematic analysis of airborne ultra‐wideband radar data. We evaluate basal roughness and basal return echoes in the context of the current ice stream geometry and ice surface velocity. We observe a change from a smooth to a rougher bed where the ice stream widens, and a distinct roughness anisotropy, indicating a preferred orientation of subglacial structures. In the upstream region, the excess ice mass flux through the shear margins is evacuated by ice flow acceleration and along‐flow stretching of the ice. At the downstream part, the generally rougher bed topography correlates with a decrease in flow acceleration and lateral variations in ice surface velocity. Together with basal water routing pathways, this hints to two different zones in this part of the NEGIS: the upstream region collecting water, with a reduced basal traction, and downstream, where the ice stream is slowing down and is widening on a rougher bed, with a distribution of basal water toward the shear margins. Our findings support the hypothesis that the NEGIS is strongly interconnected to the subglacial water system in its onset region, but also to the subglacial substrate and morphology.
Beyond Stationarity: Influence of Flow History and Sediment Supply on Coarse Bedload Transport
Authors: Downs P. W. , Soar P. J.
Published: December 2020

Understanding how river bedload responds to climate and land use changes and water resource management initiatives is critical in developing sustainable approaches to river management. Passive monitoring techniques permit investigation of interannual dependencies in bedload transport in high resolution, including sediment supply factors. Here, seismic impact plate records are processed using a probabilistic model BedLoad from Impact Plates model to derive a 5‐year bedload data set at 5‐min intervals for the lower River Avon, Devon, UK. For water years that range from very dry to very wet, annual coarse bedload yields are estimated to vary through two orders of magnitude with wide prediction intervals. The most effective discharge occurs consistently at about one‐third of bankfull flow, morphologically at “subbarfull” stage, the result of hysteretic trends and falling limb transport in this non‐threshold channel. A two‐phase sediment rating curve is revealed with a variable supply related “bulge” during in‐bank flows, giving way to a near‐linear trend during overbank flows. The supply related component is predicted well using a sensitivity style metric that combines the cumulative duration of competent flows with the magnitude‐duration product of near‐threshold flows, defining a field‐scale exemplar of “stress history.” Further, the relative proportion of supply related coarse bedload yield relates strongly to the relative wetness of the previous year. High resolution, multiyear data reveal that controls on bedload dynamics are unique to a site's hydrogeoclimatic context and position in the river basin. Passive monitoring holds promise for generating “type sites” of bedload behavior critical for use in improving aquatic biodiversity and the sustainability of river management.
Zigzag gas phases on holey adsorbed layers
Authors: Teshima Hideaki , Nakamura Naoto , Li Qin-Yi , Takata Yasuyuki , Takahashi Koji
Published: December 2020

Heating induces the formation of novel zigzag gas phases on the holey adsorbed air layers.
Fairness‐aware nonlinear joint transceiver design for energy‐harvesting‐powered CoMP systems
Authors: Hu Zhirui , Xu Fangmin , He Meilin , Lu Conghui , Zheng Changliang
Published: December 2020

This paper focuses on the fairness‐aware nonlinear joint transceiver design for the energy‐harvesting (EH)‐powered coordinated multi‐point (CoMP) systems. In the EH‐powered CoMP systems, each node harvests the energy independently first. Then, these nodes collaborate for joint signal transmission. Since there is no conventional grid to connect the nodes, the energy among nodes cannot be coordinated. Therefore, per‐node power constraints should be satisfied, which however has not been considered in existing schemes. In this paper, a fairness‐aware nonlinear transceiver scheme is developed under the per‐node power constraints. The nonlinear transceiver design is formulated as an optimization problem to maximize the minimum signal‐to‐interference noise ratio of data streams. A two‐step optimization algorithm is proposed to obtain the closed‐form solutions in the cases with perfect channel state information (CSI) and imperfect CSI, respectively. Simulation results verify the fairness of the proposed algorithm, and demonstrate its performance enhancement in sum‐rate and bit ratio error (BER). For sum‐rate, the proposed algorithm can achieve 12% gain over WS‐MSE and 40% gain over BD at SNR = 20 dB. For BER, it can achieve an approximately 4 dB gain over WS‐MSE and 8 dB gain over BD at BER = 10−3.
Adaptive stochastic model predictive control of linear systems using Gaussian process regression
Authors: Li Fei , Li Huiping , He Yuyao
Published: December 2020

This paper presents a stochastic model predictive control method for linear time‐invariant systems subject to state‐dependent additive uncertainties modelled by Gaussian process (GP). The new method is developed by re‐building the tube‐based model predictive control framework with chance constraints via adaptive constraint tightening. In particular, the tightened constraint set is constructed by forecasting the confidence region of uncertainty. Utilising this adaptive strategy, the Gaussian process based stochastic model predictive control (GP‐SMPC) algorithm is designed by applying the adaptive tightened constraints in all prediction horizons. To reduce the computation load, the one‐step GP‐SMPC algorithm is further developed by imposing the tightened constraints only to the first‐step nominal state and the worst‐case constraints to the remaining steps. Under the assumption that the state‐dependent uncertainties are bounded, the recursive feasibility of the designed optimisation problem is ensured, and the closed‐loop system stability is guaranteed. The effectiveness and advantage over existing methods are verified via simulation and comparison studies.
Measurements and channel modeling of low and medium voltage NB‐PLC networks for smart metering
Authors: Masood Bilal , Guobing Song , Naqvi Rizwan Ali , Rasheed Muhammad Babar , Hou Junjie , Rehman Ateeq Ur
Published: December 2020

This paper aims to investigate the feasibility of smart metering system based on narrowband power line communications (NB‐PLC) by using low‐voltage (LV) and medium‐voltage (MV) power line channels. The LV and MV networks of two different sites are selected to carry out comprehensive field measurements to investigate the characteristics of NB‐PLC channels for narrowband frequencies. The NB‐PLC channels of both sites are classified into two categories, that is, bad and good channels of LV and MV networks by considering their characteristics and performance. On the basis of measured results, the simulation models for the modeling of LV and MV NB‐PLC channels are developed and thus proposed. The measured and simulated results are compared to validate the efficiency of proposed methods. A state of the art mechanism for the modelling of capacitative coupling device and impedances of LV and MV networks is developed. It is proposed that simulation‐based NB‐PLC channel models and analyses can play a vital role in examining the residential and industrial types of channels. This research work will pave the way to standardize the future smart metering equipment and sensing devices of power system protection.
Uninterrupted power supply to BESS based microgrid system using adaptive reclosing approach
Authors: Ghore Shubham , Das Pinku , Biswal Monalisa
Published: December 2020

As more than 80% of faults on overhead lines are temporary (transient) in nature which is caused due to lightning strikes, momentary bird or tree limb contact, wind bringing conductors in contact, etc. These type of faults gets cleared by itself in a short duration. But the use of a conventional reclosing scheme results in an outage time which is much larger than the actual fault duration. This is due to the use of fixed dead times in conventional reclosing schemes. This unnecessary outage results in increased consumption of stored energy of energy storage system causing considerable losses. This paper proposes an empirical mode decomposition based adaptive reclosing technique which can sense the exact instant of fault clearance and modify the prefixed dead time to an adaptive value. Within half cycle time period after fault clearance reclosing command can be issued for the breaker. The performance of the proposed algorithm is verified in a modified IEEE 13 bus distribution network model considering a battery energy storage system and hybrid distributed generators. The simulation and modelling of the various fault cases in the microgrid structure are done using EMTDC/PSCAD software.
Tactics for improving computational performance of criticality analysis in state estimation
Authors: Braga Flôr Vinícius B. , Do Coutto Filho Milton B. , Stacchini de Souza Julio C. , Augusto Andre A.
Published: December 2020

Power system state estimation is a needful tool for providing reliable data on the system operating conditions. As such, state estimation requires adequate data redundancy levels, which can be expressed in terms of the degrees of criticalities associated with different groups of measurements. Criticality analysis allows the assessment of the potential risks that could impact state estimation results. The identification of criticalities is a computationally‐intensive process owing to the combinatorial nature of the problem. This paper proposes some Branch‐and‐Bound‐based tactics geared up for improving the computational efficiency of criticality analysis in state estimation. Throughout the paper, the authors sum up significant advances concerning their previous research, in terms of branching and bounding operations, choice of search strategies, data structures adopted, the proposition of a coefficient of criticality, uninformed and informed search schemes, different ways of objective function evaluation, and exploration of different objectives to be accomplished. Simulation results obtained on the IEEE 118‐bus test system evince the performance of the proposed algorithms.
GaiaEarly Data Release 3
Authors: Lindegren L. , Bastian U. , Biermann M. , Bombrun A. , de Torres A. , Gerlach E. , Geyer R. , Hernández J. , Hilger T. , Hobbs D. , Klioner S. A. , Lammers U. , McMillan P. J. , Ramos-Lerate M. , Steidelmüller H. , Stephenson C. A. , van Leeuwen F.
Published: December 2020

Context. GaiaEarly Data Release 3 (GaiaEDR3) gives trigonometric parallaxes for nearly 1.5 billion sources. Inspection of the EDR3 data for sources identified as quasars reveals that their parallaxes are biased, that is, they are systematically offset from the expected distribution around zero, by a few tens of microarcseconds.

Aims.We attempt to map the main dependences of the parallax bias in EDR3. In principle, this could provide a recipe for correcting the EDR3 parallaxes.

Methods.Quasars provide the most direct way for estimating the parallax bias for faint sources. In order to extend this to brighter sources and a broader range of colours, we used differential methods based on physical pairs (binaries) and sources in the Large Magellanic Cloud. The functional forms of the dependences were explored by mapping the systematic differences between EDR3 and DR2 parallaxes.

Results.The parallax bias is found to depend in a non-trivial way on (at least) the magnitude, colour, and ecliptic latitude of the source. Different dependences apply to the five- and six-parameter solutions in EDR3. While it is not possible to derive a definitive recipe for the parallax correction, we give tentative expressions to be used at the researcher’s discretion and point out some possible paths towards future improvements.
Hierarchical minimization of two maximum costs on a bounded serial-batching machine
Authors: He Cheng , Lin Hao , Li Li
Published: December 2020

This paper studies a hierarchical optimization problem of scheduling n jobs on a serial-batching machine, in which two objective functions are maximum costs. By a hierarchical optimization problem, we mean the problem of optimizing the secondary criterion under the constraint that the primary criterion is optimized. A serial-batching machine is a machine that can handle up to b jobs in a batch and jobs in a batch start and complete respectively at the same time and the processing time of a batch is equal to the sum of the processing times of jobs in the batch. When a new batch starts, a constant setup time s occurs. We confine ourselves to the bounded model, where b < n. We present an O(n4)-time algorithm for this hierarchical optimization problem. For the special case where two objective functions are maximum lateness, we give an O(n3 log n)-time algorithm.
Multiple Osteochondromas Comorbid With Enlarged Parietal Foramina, Elongated Styloid Processes, and Tibiofibular Synostosis
Authors: Baugher Elizabeth C , Batarseh Tamara R , Becker Ashley K , Cantu Austin J , Carr Evan W , Sakthi Velavan Sumathilatha
Published: December 2020

Objectives

This study investigates a unique case of multiple osteochondromas (MO) comorbid with enlarged parietal foramina and correlates the findings with the existing literature. The aim of this study is to provide a deeper understanding of anatomic variation for physicians.

Methods

A 66-year-old White male donor was examined during a routine cadaveric dissection performed by medical students in an anatomy laboratory. Detailed exploration of the skeleton and organs was performed, and photographs were taken. Tissue samples were obtained from multiple outgrowths, and histopathologic examination was done.

Results

Bilateral bony growths were noted rising from the long bones of the upper and lower extremities (femur, tibia, fibula, and radius). An accessory muscle was found to be associated with the left radial bony growth. Histopathologic examination was positive for osteochondroma. Inspection of the skull revealed enlarged parietal foramina. Other findings included tibiofibular synostosis, abnormally shaped vertebral bodies and ribs, and elongated styloid processes of the skull.

Conclusions

In combination with the histopathologic examination, the case report and literature review elucidate a more precise clinical picture for those affected with MO or similar disorders. This report also emphasizes the necessity of further investigation of the pathogenesis of MO and Potocki-Shaffer syndrome.
Maturation of Complex Synaptic Connections of Layer 5 Cortical Axons in the Posterior Thalamic Nucleus Requires SNAP25
Authors: Hayashi Shuichi , Hoerder-Suabedissen Anna , Kiyokage Emi , Maclachlan Catherine , Toida Kazunori , Knott Graham , Molnár Zoltán
Published: December 2020

Synapses are able to form in the absence of neuronal activity, but how is their subsequent maturation affected in the absence of regulated vesicular release? We explored this question using 3D electron microscopy and immunoelectron microscopy analyses in the large, complex synapses formed between cortical sensory efferent axons and dendrites in the posterior thalamic nucleus. Using a Synaptosome-associated protein 25 conditional knockout (Snap25 cKO), we found that during the first 2 postnatal weeks the axonal boutons emerge and increase in the size similar to the control animals. However, by P18, when an adult-like architecture should normally be established, axons were significantly smaller with 3D reconstructions, showing that each Snap25 cKO bouton only forms a single synapse with the connecting dendritic shaft. No excrescences from the dendrites were formed, and none of the normally large glomerular axon endings were seen. These results show that activity mediated through regulated vesicular release from the presynaptic terminal is not necessary for the formation of synapses, but it is required for the maturation of the specialized synaptic structures between layer 5 corticothalamic projections in the posterior thalamic nucleus.
Impact of aortic arch curvature in flow haemodynamics in patients with transposition of the great arteries after arterial switch operation
Authors: Sotelo Julio , Valverde Israel , Martins Duarte , Bonnet Damien , Boddaert Nathalie , Pushparajan Kuberan , Uribe Sergio , Raimondi Francesca
Published: December 2020

Aims 

In this study, we will describe a comprehensive haemodynamic analysis and its relationship to the dilation of the aorta in transposition of the great artery (TGA) patients post-arterial switch operation (ASO) and controls using 4D-flow magnetic resonance imaging (MRI) data.

Methods and results 

Using 4D-flow MRI data of 14 TGA young patients and 8 age-matched normal controls obtained with 1.5 T GE-MR scanner, we evaluate 3D maps of 15 different haemodynamics parameters in six regions; three of them in the aortic root and three of them in the ascending aorta (anterior-left, -right, and posterior for both cases) to find its relationship with the aortic arch curvature and root dilation. Differences between controls and patients were evaluated using Mann–Whitney U test, and the relationship with the curvature was accessed by unpaired t-test. For statistical significance, we consider a P-value of 0.05. The aortic arch curvature was significantly different between patients 46.238 ± 5.581 m−1 and controls 41.066 ± 5.323 m−1. Haemodynamic parameters as wall shear stress circumferential (WSS-C), and eccentricity (ECC), were significantly different between TGA patients and controls in both the root and ascending aorta regions. The distribution of forces along the ascending aorta is highly inhomogeneous in TGA patients. We found that the backward velocity (B-VEL), WSS-C, velocity angle (VEL-A), regurgitation fraction (RF), and ECC are highly correlated with the aortic arch curvature and root dilatation.

Conclusion 

We have identified six potential biomarkers (B-VEL, WSS-C, VEL-A, RF, and ECC), which may be helpful for follow-up evaluation and early prediction of aortic root dilatation in this patient population.
Case report: takotsubo cardiomyopathy after transcatheter aortic valve-in-valve replacement
Authors: Steinecker Matthieu , Benvenuti Christophe , Digne Franck , Nejjari Mohammed
Published: December 2020

Background 

Transcatheter aortic valve implantation (TAVI) has become a first-line therapeutic option in patients with severe, symptomatic aortic stenosis at increased surgical risk. Despite its success, the TAVI procedure has been associated with acute life-threatening complications as myocardial infarction secondary to periprocedural coronary occlusion, annular rupture, or vascular injury.

Case summary 

A 79-year-old woman with a dysfunctional bioprosthetic valve following previous surgical valve replacement was hospitalized in our institution to perform a Valve-in-Valve Transcatheter Aortic Valve Replacement (ViV TAVR). Shortly after the implantation of an Evolut R valve (without complication), left ventricle dysfunction with apical akinesia and basal hyperkinesia was identified during bedside transthoracic echocardiography, in spite of a good prosthesis implantation and function. A concomitant Troponin elevation was noted, and the day-after resting electrocardiogram showed a lateral T-wave inversion. Coronary computed tomography angiography showed no coronary stenosis or occlusion, cardiac magnetic resonance imaging showed no necrosis or fibrosis, and no argument for myocarditis. The patient remained asymptomatic during her hospital stay, and the aforementioned anomalies spontaneously regressed after an in-hospital 2-week surveillance. In the presence of these transient anomalies and after ruling out myocardial infarction and myocarditis, post-procedural stress cardiomyopathy (takotsubo) was diagnosed.

Discussion 

Post-TAVR stress-related cardiomyopathy seems to be an extremely rare entity. To our knowledge, this is the first case of a takotsubo cardiomyopathy after ViV TAVR. Though the association between the two seems likely to be causal, no clear physiopathological explanation can be formulated.
Delayed presentation of acute coronary syndrome with mechanical complication during COVID-19 pandemic: a case report
Authors: Tan Joo Hor , Tong Jieli , Ho Hee Hwa
Published: December 2020

Background

The World Health Organization declared coronavirus disease 2019 (COVID-19) a global pandemic on 11 March 2020. We report a patient with acute myocardial infarction (AMI) who presented late due to fears of contracting COVID-19.

Case summary

A 65-year-old man with a history of hypertension presented late to the emergency department (ED) with AMI. He gave a 2-month history of exertional angina but avoided seeking medical consult due to fears of contracting COVID-19. On the day of admission, he had 4 h of severe chest pain before presenting to the ED. He was hypotensive and tachycardic on arrival. Electrocardiogram showed inferolateral ST-elevation myocardial infarction. Chest radiograph revealed widened superior mediastinum and bedside echocardiogram revealed inferoseptal and inferolateral hypokinesia with features of cardiac tamponade. An urgent computed tomography aortogram showed possible left ventricular (LV) wall perforation with resulting haemopericardium and cardiac tamponade. Subsequent coronary angiogram showed 100% occlusion of mid left circumflex artery and a contained LV wall rupture was confirmed with LV ventriculogram. He was transferred to a tertiary centre and underwent successful emergency surgical repair.

Discussion

Our index case demonstrates the impact of the COVID-19 pandemic on health seeking behaviour due to fears of contracting COVID-19 and the ensuing impact of delayed medical intervention. Cardiologists worldwide are seeing an alarming rate of rare complications of AMI in patients who present late. Physicians need to be aware of this phenomenon and have an active role to play in public education.
Characterization of version in the dysplastic hip and the need for subsequent femoral derotational osteotomy after periacetabular osteotomy
Authors: Spiker Andrea M , Fields Kara G , Nguyen Joseph T , Wong Alexandra C , Sink Ernest L
Published: December 2020

Hip dysplasia is a three-dimensional pathomechanical condition that is often more complex than the standard method of measuring lateral center edge angle (CEA) can quantify. Yet there is a paucity of literature examining the differences in version seen between dysplastic and non-dysplastic femoroacetabular impingement (FAI) hips, the relationship of acetabular and femoral version (FV) within dysplastic hips and the contribution of each of these factors to symptoms and outcomes of dysplasia treatment. We sought to describe the acetabular version (AcetV) and FV in dysplastic hips and quantify how these measurements compared with non-dysplastic FAI hips. We also sought to analyze the association of these factors with patient-reported outcomes (PROs) after periacetabular osteotomy (PAO) and determine the need for subsequent femoral derotational osteotomy after PAO. A total of 113 dysplastic patients who underwent PAO (92% female, mean age 24) were compared with 1332 (45% female, mean age 25) non-dysplastic FAI (CEA > 25°) patients. We found that dysplastic hips had a statistically higher AcetV and FV than non-dysplastic FAI hips. There was a very weak correlation between AcetV and FV in dysplastic hips, suggesting that patients with higher AcetV did not necessarily have higher FV. There was no association with AcetV or FV and patient outcomes in our very limited analysis of PROs after PAO, and only 5% of patients with excessive FV (>20°) required subsequent femoral derotational osteotomy, suggesting that in a majority of patients with hip dysplasia, FV may not impact the post-operative clinical course.
Proplyds in the flame nebula NGC 2024
Authors: Haworth Thomas J , Kim Jinyoung S , Winter Andrew J , Hines Dean C , Clarke Cathie J , Sellek Andrew D , Ballabio Giulia , Stapelfeldt Karl R
Published: December 2020

A recent survey of the inner 0.35 × 0.35 pc of the NGC 2024 star-forming region revealed two distinct millimetre continuum disc populations that appear to be spatially segregated by the boundary of a dense cloud. The eastern (and more embedded) population is ∼0.2–0.5 Myr old, with an ALMA mm continuum disc detection rate of about $45\,$ per cent. However, this drops to only $\sim 15\,$ per cent in the 1-Myr western population. When these distinct populations were presented, it was suggested that the two main UV sources, IRS 1 (a B0.5V star in the western region) and IRS 2b (an O8V star in the eastern region, but embedded) have both been evaporating the discs in the depleted western population. In this paper, we report the firm discovery in archival HST data of four proplyds and four further candidate proplyds in NGC 2024, confirming that external photoevaporation of discs is occurring. However, the locations of these proplyds changes the picture. Only three of them are in the depleted western population and their evaporation is dominated by IRS 1, with no obvious impact from IRS 2b. The other five proplyds are in the younger eastern region and being evaporated by IRS 2b. We propose that both populations are subject to significant external photoevaporation, which happens throughout the region wherever discs are not sufficiently shielded by the interstellar medium. The external photoevaporation and severe depletion of mm grains in the 0.2–0.5 Myr eastern part of NGC 2024 would be in competition even with very early planet formation.
Prognostic relevance of clinical and molecular risk factors in children with high-risk medulloblastoma treated in the phase II trial PNET HR+5
Authors: Dufour Christelle , Foulon Stephanie , Geoffray Anne , Masliah-Planchon Julien , Figarella-Branger Dominique , Bernier-Chastagner Valerie , Padovani Laetitia , Guerrini-Rousseau Léa , Faure-Conter Cecile , Icher Celine , Bertozzi Anne-Isabelle , Leblond Pierre , Akbaraly Tasnime , Bourdeaut Franck , André Nicolas , Chappé Celine , Schneider Pascale , De Carli Emilie , Chastagner Pascal , Berger Claire , Lejeune Julien , Soler Christine , Entz-Werlé Natacha , Delisle Marie-Bernadette
Published: December 2020

Background

High-risk medulloblastoma is defined by the presence of metastatic disease and/or incomplete resection and/or unfavorable histopathology and/or tumors with MYC amplification. We aimed to assess the 3-year progression-free survival (PFS) and define the molecular characteristics associated with PFS in patients aged 5–19 years with newly diagnosed high-risk medulloblastoma treated according to the phase II trial PNET HR+5.

Methods

All children received postoperative induction chemotherapy (etoposide and carboplatin), followed by 2 high-dose thiotepa courses (600 mg/m2) with hematological stem cell support. At the latest 45 days after the last stem cell rescue, patients received risk-adapted craniospinal radiation therapy. Maintenance treatment with temozolomide was planned to start between 1–3 months after the end of radiotherapy. The primary endpoint was PFS. Outcome and safety analyses were per protocol (all patients who received at least one dose of induction chemotherapy).

Results

Fifty-one patients (median age, 8 y; range, 5–19) were enrolled. The median follow-up was 7.1 years (range: 3.4–9.0). The 3 and 5-year PFS with their 95% confidence intervals (95% CI) were 78% (65–88) and 76% (63–86), and the 3 and 5-year OS were 84% (72–92) and 76% (63–86), respectively. Medulloblastoma subtype was a statistically significant prognostic factor (P-value = 0.039) with large-cell/anaplastic being of worse prognosis, as well as a molecular subgroup (P-value = 0.012) with sonic hedgehog (SHH) and group 3 being of worse prognosis than wingless (WNT) and group 4. Therapy was well tolerated.

Conclusions

This treatment based on high-dose chemotherapy and conventional radiotherapy resulted in a high survival rate in children with newly diagnosed high-risk medulloblastoma.
Prognostic Factors Associated With Surviving Less Than 3 Months vs Greater Than 3 Years Specific to Spine Stereotactic Body Radiotherapy and Late Adverse Events
Authors: Zeng K Liang , Sahgal Arjun , Tseng Chia-Lin , Myrehaug Sten , Soliman Hany , Detsky Jay , Atenafu Eshetu G , Lee Young , Campbell Mikki , Maralani Pejman , Husain Zain A
Published: December 2020

BACKGROUND

Patient selection is critical for spine stereotactic body radiotherapy (SBRT) given potential for serious adverse effects and the associated costs.

OBJECTIVE

To identify prognostic factors associated with dying within 3 mo, or living greater than 3 yr, following spine SBRT, to better inform patient selection.

METHODS

Patients living ≤3 mo after spine SBRT and >3 yr after spine SBRT were identified, and multivariable regression analyses were performed. We report serious late toxicities observed, including vertebral compression fractures (VCF) and plexopathy.

RESULTS

A total of 605 patients (1406 spine segments) were treated from 2009 to 2018. A total of 51 patients (8.4%) lived ≤3 mo, and 79 patients (13%) survived >3 yr. Significant differences in baseline features were observed. On multivariable analysis, nonbreast/prostate primaries (odds ratio [ORs]: 28.8-104.2, P = .0004), eastern cooperative oncology group (ECOG) ≥2 (OR: 23.7, 95% CI: 3.2-177, P = .0020), polymetastatic disease (OR: 6.715, 95% CI: 1.89-23.85, P = .0032), painful lesions (OR: 3.833-8.898, P = .0118), and paraspinal disease (OR: 2.874, 95% CI: 1.118-7.393, P = .0288) were prognostic for ≤3 mo survival. The 3- and 5-yr rates of VCF were 10.4% and 14.4%, respectively, and 3- and 5-yr rates of plexopathy were 2.2% and 5.1%, respectively. A single duodenal perforation was observed, and there was no radiation myelopathy events.

CONCLUSION

Shorter survival after spine SBRT was seen in patients with less radiosensitive histologies (ie, not breast or prostate), ECOG ≥2, and polymetastatic disease. Pain and paraspinal disease were also associated with poor survival. Fractionated spine SBRT confers a low risk of late serious adverse events.
Longitudinal Dose Trajectory Among Patients Tapering Long-Term Opioids
Authors: Fenton Joshua J , Magnan Elizabeth M , Agnoli Alicia L , Henry Stephen G , Xing Guibo , Tancredi Daniel J
Published: December 2020

Objective

To evaluate the dose trajectory of new opioid tapers and estimate the percentage of patients with sustained tapers at long-term follow-up.

Design

Retrospective cohort study.

Setting

Data from the OptumLabs Data Warehouse® which includes de-identified medical and pharmacy claims and enrollment records for commercial and Medicare Advantage enrollees, representing a diverse mixture of ages, ethnicities, and geographical regions across the United States.

Subjects

Patients prescribed stable, higher-dose opioids for ≥12 months from 2008 to 2018.

Methods

Tapering was defined as ≥15% relative reduction in average MME/day during any of six overlapping 60-day periods in the initial 7 months of follow-up after the period of stable baseline dosing. Average monthly dose was ascertained during consecutive 60-day periods up to 16 months of follow-up. Linear regression estimated the geometric mean relative dose by tapering status and follow-up duration. Poisson regression estimated the percentage of tapered patients with sustained dose reductions at follow-up and patient-level predictors of failing to sustain tapers.

Results

The sample included 113,618 patients with 203,920 periods of stable baseline dosing (mean follow-up = 13.7 months). Tapering was initiated during 37,170 follow-up periods (18.2%). After taper initiation, patients had a substantial initial mean dose reduction (geometric mean relative dose .73 [95% CI: .72–.74]) that was sustained through 16 months of follow-up; at which point, 69.8% (95% CI: 69.1%–70.4%) of patients who initiated tapers had a relative dose reduction ≥15%, and 14.2% (95% CI: 13.7%–14.7%) had discontinued opioids. Failure to sustain tapers was significantly less likely among patients with overdose events during follow-up (adjusted incidence rate ratio [aIRR]: .56 [95% CI: .48–.67]) and during more recent years (aIRR: .93 per year after 2008 [95% CI: .92–.94]).

Conclusions

In an insured and Medicare Advantage population, over two-thirds of patients who initiated opioid dose tapering sustained long-term dose reductions, and the likelihood of sustaining tapers increased substantially from 2008 to 2018.
Bigger juveniles and smaller adults: Changes in fish size correlate with warming seas
Authors: Ikpewe Idongesit E. , Baudron Alan R. , Ponchon Aurore , Fernandes Paul G.
Published: December 2020

Increasing sea temperatures are predicted to decrease body size of marine ectotherms based on the temperature size rule. This will impact fisheries yields, but empirical evidence of the process is still limited.

We used fishery‐independent bottom trawl survey data from 1970 to 2017 to examine the trends of length‐at‐age of four commercially important demersal fish species (cod, haddock, whiting and saithe) in two study areas facing increasing sea temperatures: the West of Scotland and the North Sea. We then compared the trends of length‐at‐age with annual bottom sea temperatures.

The mean length‐at‐age of adults declined over the study period, in all species and in both areas, except for cod in the West of Scotland. A common trend of decline in adult length was inversely correlated with bottom sea temperatures. Correlations with temperature at seven yearly time‐lags were significant and negative in the North Sea. Correlations were only significant at lags of 1 and 2 years in the west of Scotland, where sea temperature warming was twice as slow.

The mean length‐at‐age of juveniles concurrently increased, which has not hitherto been reported. This trend, shared by all species and both regions, correlated positively with rising temperature, suggesting that our study species have a faster growth rate due to increased temperatures.

Synthesis and applications. We examined the body size of a range of commercially exploited fish species, at different age groups, from two management regions. We found that juvenile fish have been getting bigger and adults smaller in both regions. These changes were correlated with rising sea temperatures, providing empirical evidence that global warming is affecting the size of commercial fish species. The effects of these changes on productivity of fish populations and fisheries yield now require investigation. Temperature changes should, therefore, be included into forecasts used in fisheries science in order to mitigate the impact of global warming and maximise sustainable yields.
Student and supervisor experiences of the Systemic Practice Scale (SPS): a discourse analysis
Authors: Parker Claire , Smithson Janet , Limond Jennifer , Sherbersky Hannah , Butler Catherine
Published: December 2020

There has been recent emphasis on the assessment of competence in psychotherapy training courses to improve evidence‐based practice and outcomes for clients. The Systemic Practice Scale (SPS) was developed as a structured way of evaluating systemic practice. There is, however, little research on the impact and experience of competence measures, particularly in the context of systemic practice. Five focus groups conducted with sixteen students and seven supervisors from systemic family practice (SFP) programmes explored their views of the SPS as an appropriate measure of systemic competence. Data was analysed using a discourse analysis with three dominant discourses identified:feedback as valuable but uncomfortable;measuring competence; andbeing systemic. The SPS was viewed as a valuable and useful measure of systemic competence when reflexivity and collaboration is maintained between the student and supervisor.

Practitioner points

There is limited research exploring the use of competence measures in systemic practice

The SPS was perceived as broadening perspectives of students’ practice and competence, reiterating the importance of feedback in a collaborative supervisory relationship

Increasingly the SPS is being used across clinical psychotherapy training courses (including systemic IAPT course and Doctorate of Clinical Psychology)

It has the potential to be used more widely with wider implications for the development of systemic training standards in systemic practice
Suspicion and expertise: following the money in an offshore investigation
Authors: Fedirko Taras
Published: December 2020

This article explores the relation between suspicion and expertise in the context of activist investigations of offshore corruption. I reconstruct one investigation of alleged corruption in the Azerbaijani oil sector, conducted by a British organization called Global Witness, to explore how suspicion is learned and practised in the face of impenetrable offshore secrecy. For these detectives of global capital, suspicion is both a tool for arriving at an understanding of offshore corporate networks and an orientation that helps them overcome the limits of this understanding, allowing them to make political claims that go beyond what is strictly afforded by evidence and libel law. Extending recent anthropological scholarship that revises the disciplinary emphasis on truth and certainty as the mainstays of expert knowledge, I argue that investigative expertise provides imprecise and suspicious understandings of its objects that are useful despite, or even because of, the ambivalence and suspicion it entails.
Population Health Science: Fulfilling the Mission of Public Health
Authors: ZIMMERMAN FREDERICK J.
Published: December 2020

Policy Points

The historical mission of public health is to ensure the conditions in which people can be healthy, and yet the field of public health has been distracted from this mission by an excessive reliance on randomized‐control trials, a lack of formal theoretical models, and a fear of politics.

The field of population health science has emerged to rigorously address all of these constraints. It deserves ongoing and formal institutional support.
Pregnancy and phaeochromocytoma/paraganglioma: clinical clues affecting diagnosis and outcome – a systematic review
Authors: Langton K , Tufton N , Akker S , Deinum J , Eisenhofer G , Timmers HJLM , Spaanderman MEA , Lenders JWM
Published: December 2020

Background

Phaeochromocytoma and paraganglioma (PPGL) in pregnancy, if not diagnosed antepartum, pose a high risk for mother and child.

Objective

To examine the clinical clues of antepartum and postpartum/postmortem diagnosis of PPGL.

Search strategy

Case reports on PPGL in pregnancy published between 1 January 1988 and 30 June 2019 in English, German, Dutch or French.

Selection criteria

Case reports containing a predefined minimum of clinical data on PPGL and pregnancy.

Data collection and analysis

Two authors independently performed data extraction and assessed data quality. We calculated odds ratios (OR) (with 95% confidence intervals) and used uni‐ and multivariable logistic regression analysis.

Main results

Maternal and fetal/neonatal mortalities were 9.0% (18/200) and 14.2% (29/204), respectively. Maternal mortality was 42‐fold higher with PPGL diagnosed postpartum/postmortem (17/58; 29.3%) than antepartum (1/142; 0.7%) (adjusted OR 45.9, 95% CI 5.67–370, P = 0.0003). Offspring mortality was 2.6‐fold higher with PPGL diagnosed postpartum/postmortem than antepartum (OR 3.1, 95% CI 1.38–6.91, P = 0.0044). Hypertension at admission (OR 2.29, 95% CI 1.12–4.68, P = 0.022), sweating (OR 3.14, 95% CI 1.29–7.63, P = 0.014) and a history of PPGL, a known PPGL‐associated gene mutation or adrenal mass (OR 8.87, 95% CI 1.89–41.64, P = 0.0056) were independent factors of antepartum diagnosis. Acute onset of symptoms (OR 8.49, 95% CI 3.52–20.5, P < 0.0001), initial diagnosis of pre‐eclampsia (OR 6.34, 95% CI 2.60–15.5, P < 0.0001), admission for obstetric care (OR 10.71, 95% CI 2.70–42.45, P = 0.0007) and maternal tachycardia (OR 2.72, 95% CI 1.26–5.85, P = 0.011) were independent factors of postpartum diagnosis.

Conclusion

Several clinical clues can assist clinicians in considering an antenatal diagnosis of PPGL in pregnancy, thus potentially improving outcome.

Tweetable abstract

Systematic review of 204 pregnant patients with phaeochromocytoma identified clinical clues for a timely antepartum diagnosis.
We and herbivores eat endophytes
Authors: Martínez‐Romero Esperanza , Aguirre‐Noyola José Luis , Bustamante‐Brito Rafael , González‐Román Pilar , Hernández‐Oaxaca Diana , Higareda‐Alvear Víctor , Montes‐Carreto Leslie M. , Martínez‐Romero Julio César , Rosenblueth Mónica , Servín‐Garcidueñas Luis Eduardo
Published: December 2020

Health depends on the diet and a vegetal diet promotes health by providing fibres, vitamins and diverse metabolites. Remarkably, plants may also provide microbes. Fungi and bacteria that reside inside plant tissues (endophytes) seem better protected to survive digestion; thus, we investigated the reported evidence on the endophytic origin of some members of the gut microbiota in animals such as panda, koala, rabbits and tortoises and several herbivore insects. Data examined here showed that some members of the herbivore gut microbiota are common plant microbes, which derived to become stable microbiota in some cases. Endophytes may contribute to plant fibre or antimetabolite degradation and synthesis of metabolites with the plethora of enzymatic activities that they display; some may have practical applications, for example, Lactobacillus plantarum found in the intestinal tract, plants and in fermented food is used as a probiotic that may defend animals against bacterial and viral infections as other endophytic‐enteric bacteria do. Clostridium that is an endophyte and a gut bacterium has remarkable capabilities to degrade cellulose by having cellulosomes that may be considered the most efficient nanomachines. Cellulose degradation is a challenge in animal digestion and for biofuel production. Other endophytic‐enteric bacteria may have cellulases, pectinases, xylanases, tannases, proteases, nitrogenases and other enzymatic capabilities that may be attractive for biotechnological developments, indeed many endophytes are used to promote plant growth. Here, a cycle of endophytic‐enteric‐soil‐endophytic microbes is proposed which has relevance for health and comprises the fate of animal faeces as natural microbial inoculants for plants that constitute bacterial sources for animal guts.
Biocorrosion caused by microbial biofilms is ubiquitous around us
Authors: Dou Wenwen , Xu Dake , Gu Tingyue
Published: December 2020

Biocorrosion first surfaced in the scientific literature when Richard H. Gaines associated corrosion with bacterial activities in 1910. It is also known as microbiologically influenced corrosion (MIC). In general, it covers two scenarios. One is that microbes cause corrosion directly, which usually means microbes secrete corrosive metabolites or microbes harvest electrons from a metal for respiration to produce energy. In the second scenario, microbes are behind the initiation or acceleration of corrosion caused by a pre‐existing corrosive agent such as water and CO2, by compromising the passive film (often a metal oxide film on a metal). MIC is caused by microbial biofilms. It is everywhere around us. This work dissects some notable examples with perspectives.