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Carbon fiber composite cylinders were fabricated using the filament winding technique, and the cylinders were loaded internally with a high-energy explosive material. As the high-energy explosive material detonated, the transient deformation and failure of the composite cylinder were investigated both experimentally and numerically. For the experimental study, a high-speed video camera running at 5 million frames per second was used to capture the deformation and failure of the composite cylinder. A Photonic Doppler Velocimetry (PDV) system was also used to measure the radial velocity of the outer wall of the cylinder while the internal detonation progressed. Separately, Split Hopkinson Pressure Bar (SHPB) tests were conducted to check the strain-rate effect on the failure strength of the carbon fiber material. Finally, a multiscale approach was used to model the dynamic deformation and failure of the composite cylinder. The multiscale technique considers the failure of composites in terms of the constituent materials like fiber and matrix materials. The numerically predicted deformation and failure agreed well with the experimentally observed and measured results.

After 2 decades of limited growth, living donor liver transplant (LDLT) has been increasingly accepted as a promising solution to the growing organ shortage in the US. With experience, LDLT offers superior graft and patient survival with low rates of rejection. However, not all waitlisted patients have equal access to LDLT, with financial toxicity representing a substantial barrier. Potential living liver donors face indirect, direct, and opportunity costs associated with donation as well as insurance-based discrimination and variable employer leave policies. There are multiple potential national, local, and patient-centered solutions to address some of the cost-related issues associated with living LDLT. These include standardization of employer leave policies, creation of federal and state-led tax relief programs, optimization of National Living Donor Assistance Center use, engagement of independent living donor advocates, creation of financial toolkits, and encouragement of recipient or donor-led fundraising. In this piece, members of the North American Living Liver Donation Group, a consortium of 37 LDLT programs, explore these financial challenges and discuss solutions to achieve financial neutrality, where individuals can donate free from financial constraints or gains. As a community, it is imperative that we confront factors driving financial toxicity to improve equity and access to LDLT.

Many metals used in engineering applications are exposed to aging conditions such as ultraviolet radiation and moisture. Aged metals are expected to lose their designed mechanical properties, and it was desired to relate a degraded local property to other homogenous properties. To study the aging effect, steel and aluminum were tested with reproduced variables in an accelerated weather testing chamber. Multiple tensile specimens of steel and aluminum were created to undergo accelerated Q-Lab Ultraviolet testing in the presence of radiation, heat and moisture. Accelerated aging resulted in decreasing surface hardness correlating with the tensile strength and elastic modulus for both steel and aluminum. The study also investigated the change in hardness through the depth of specimens resulting from aging, exhibited more consistently in steels. The overall strongest correlations existed in steels, between surface hardness and tensile strength, analogous to other studies. Modeling linear relationships for metal lifetime forecasts from hardness has been supported by this study. Outcomes can be expanded upon with more elaborate finite element analysis if desired in future experimentation.

An analytical model was developed to predict the cyclic fatigue failure of laminated fibrous composites which may have any layup orientations with or without notches like perforated holes. The cyclic failure of laminated fibrous composites was predicted by tracking the progressive failure of fibers embedded in the composites at critical locations. The analytical model consists of multiple techniques. First, a multiscale technique is used to determine the stresses in the fibers in composite structural members subjected to cyclic loading. The unified failure criterion is used to determine the maximum fiber stresses at critical locations when the composite structural members fail under static loading. Then, a progressive fiber failure model is used to track the fatigue damage in the composite structural members. The proposed cyclic fatigue failure model was validated against various cases such as dry fiber bundles, and laminated composites with or without a notch subjected to uniform or non-uniform magnitudes of cyclic loading.

The failure criterion based on both stress and stress-gradient failure conditions was used to understand and predict the failures of two different scenarios. The first scenario was to understand why a very small hole, compared to the specimen’s dimension, does not affect the failure load even though it still has a high stress concentration at the hole's edge. Both the failure criterion and an experimental study using a high-speed camera consistently showed that failure initiated a small distance away from the hole so that the stress concentration does not affect the failure if the hole is much smaller than the specimen width. The second case of study was perforated specimens loaded by an inserted pin through the holes because the failure characteristics are quite different depending on the loading conditions. Six different types of test specimens were used in the study. The failure stress, failure locations, and initial failure orientations were measured and were also predicted using the failure criterion. Both predicted and measured results agreed well, in general, for all the test specimens even though the failure characteristics of the tested specimens demonstrated pronounced sensitivity to specimen width and hole location.

Fluid–structure interaction (FSI) induced by undulated flows was investigated using a channel driven cavity flow (CDCF) system. The bottom of the cavity section has a flexible plate made of either an aluminum alloy or carbon fiber composite, which interacts with flows in the cavity. Undulating flows were generated by controlling a series of solenoid valves programmed to interrupt the flow at various different frequencies from 0.5  to 1.25 Hz. Mean flow velocity was also varied for each given undulation frequency. The dynamic motion of the flexible test panel, made of aluminum alloy or carbon fiber composite, was measured for transverse deflections using laser displacement sensors. The study showed that the structural response was very dependent on the input flow. The plate vibrational modes had three to five dominant frequencies ranging from the undulated flow frequencies to about 5.0 Hz. Those frequencies were either at or very close to the multiples of the flow frequencies. The most dominant frequency was not always the same as the flow frequency, but it varied depending on the applied flow frequency.

During combat, naval vessels may be subjected to underwater explosions that impart shock loading onto the ship structure, its subsystems, equipment, and crew. This violent shock loading can cause considerable damage and even failure of critical components, potentially rendering vital systems inoperable and the ship unable to perform its mission. To prevent unwanted failure, shipboard equipment must be assessed for shock hardness to ensure survivability. To this end, a set of failure criteria were developed related to functional failure. These criteria are based on the dynamic response of the equipment such that they can be applied to any loading condition regardless of the support structure configuration or location within the ship system. To evaluate the developed functional failure criteria, a series of computer simulations were performed using standard shock platform and ship models with a proposed simple equipment model representing the functional failure. The developed failure criteria were based on the threshold values for the peak velocity response and the critical change in displacement. The numerical study provided good validation of the proposed failure criteria. Additionally, simplified equipment models were presented as options for increasing the computational efficiency of modeling equipment installed in large complex structures such as ships.

This paper investigated the characteristics of fiber bundles which are used for fibrous composite materials. Unembedded or dry fiber bundles were tested under monotonically increasing tensile loading. A statistical model was developed based on the slack fibers to explain the test results of the unembedded fiber bundles. Then, the behavior of the unembedded fiber bundles was compared to the fiber bundles embedded in composite materials, i.e., fiber bundles present in a matrix material. Next, unembedded fibers under tensile cyclic loadings with the displacement control mode were examined. The cyclic test results were also predicted using the statistical slack model. Finally, the residual strength and stiffness of fiber bundles were determined after undergoing different numbers of cyclic loads. Tensile tests were conducted for the same fiber bundles until failure after they were subjected to the specified cyclic loading. These tests provided data for the reduction in strength and stiffness of the fiber bundles resulting from the cyclic loading. These results would then be used in generating a cyclic fatigue failure model based on the multiscale approach that uses the cyclic test data of fibers and matrix materials instead of those of composite specimens.

This paper investigated energy harvesting from ocean waves using an oscillating column (OC) and a triboelectric nanogenerator (TENG). First, preliminary tests were conducted for a TENG fabricated using copper alloy or pure copper and polytetrafluoroethylene (PTFE) tape. Then, an OC was designed and built with the pure copper TENG, which was tested previously. The final design was tested in a tow tank with a wave maker to demonstrate the OC–TENG system under simulated ocean waves. The study examined different parameters that influenced the power generation, i.e., the voltage of alternative currents, in order to determine what parameters are critical to higher power generation.

Recently, a set of failure criteria based on a multiscale model was developed for fibrous composites. Those criteria used stresses and strains occurring in the fiber and matrix material level. The failure criteria consisted of three failure modes such as fiber failure, matrix failure, and fiber/matrix interface failure. Those criteria were developed for quasi-static loading such that the effect of the strain rate was not under consideration. To model and predict failure of composite materials and structures subjected to dynamic loading, the effect of strain rate needs to be included in the failure criteria. The present work is to revise the former criteria to be applicable to the strain rate dependent composite materials, especially polymer composites. To validate the revised failure criteria, Charpy impact testing as well as quasi-static uniaxial testing were conducted. The test results agreed well with predicted failure loads using the new failure criteria.

Dynamic response of a round aluminum tube supported at both ends was investigated when impacted at its center by an external mechanical loading. The tube was subjected to different conditions. First, the empty tube was tested. Then the tube was filled with different amounts of stationary water (i.e., 25, 50, 75, and 100% full), based on the inner volume of the tube. Finally, flowing water through the tube was considered. Different magnitudes of impact loading were also applied. The study was primarily conducted experimentally with some additional numerical studies completed to further understand the results. The impact force as well as strain along the tube were measured for all described test conditions. Their results were compared. Additionally, the vibrational frequency and damping of the system were examined using strain–time histories. The results showed that the dynamic behavior of the tube was significantly dependent on the amount of internal water as well as its flow condition.

[11C]-PBR28 is a positron emission tomography (PET) radioligand targeting the 18-kDa translocator protein (TSPO). The expression of this protein is highly upregulated in the central nervous system (CNS) during neuroinflammatory responses (mostly glial cells). TSPO PET radioligands are also expressed outside of the CNS in the peripheral/circulating immune cells. As a result, TSPO has been used as a marker of peripheral (in addition to central) inflammation. For instance, elevated uptake of [11C]-PBR28 signal has been reported in ipsilateral lumbar neuroforamen, among patients with lumbar radiculopathy. Furthermore, a recent study among patients with rheumatoid arthritis showed significantly higher [11C]-PBR28 signal in affected knees compared with healthy knee joints. The highest TSPO expression was reported on activated fibroblast-like synoviocytes as well as undifferentiated and reparative macrophages. However, no study has yet imaged [11C]-PBR28 PET uptake in a group of knee osteoarthritis (OA) patients.

Dynamic response of two concentric horizontal composite cylinders containing water in the annulus was investigated under impact loading so as to examine the load transfer from the outer cylinder to the inner through a fluid medium. Different water filling levels in the annulus were considered along with different magnitudes of impact loading. Both of the composite cylinders were 254 mm long, had a diameter of 76.2 mm and 88.9 mm, respectively, and were assembled concentrically. Both experimental and numerical studies were conducted to supplement each other. The experimental set-up was designed and constructed. Both cylinders were constrained at both ends, and the water level was varied in the annulus of the two cylinders. The experimental set-up used strain gages at certain locations. For each experiment, the strain data were collected and examined. Then, the fast Fourier transform was applied to the strain data to identify major vibrational frequencies and to examine the effect of the added mass. The numerical study provided additional results which were not measured by the experiment, such as the fluid pressure in the annulus and the dynamic motion of the cylinders. The fluid–structure interaction resulted in significant coupling of the outer and inner composite cylinders.

Material surfaces can be modified to become superhydrophobic using different techniques. Test equipment is necessary to assess the effectiveness of a superhydrophobic surface against frictional drag force. Because the frictional drag force is very small, especially for a sample size to be tested at a laboratory level, a traditional water channel system is not suitable. As a result, a new test setup was designed and fabricated to measure the reduction in the skin frictional drag force on such a superhydrophobic metallic surface. Two different types of sensors were considered. The first one was a spring-based displacement sensor and the other was a spring-less displacement sensor. The developed test setup can have the flow speed with a range of Reynolds numbers up to 70,000 with respect to the test specimen. In this range, the change in the frictional drag force was measured for superhydrophobic surfaces. A microscope was also used to check any change in the air film on the superhydrophobic surface as the flow speed was increased.

AimsThe aim of this study was to investigate the effects of preoperative bisphosphonate treatment on the intra- and postoperative outcomes of arthroplasty of the shoulder. The hypothesis was that previous bisphosphonate treatment would adversely affect both intra- and postoperative outcomes.Patients and MethodsA retrospective cohort study was conducted involving patients undergoing arthroplasty of the shoulder, at a single institution. Two patients with no previous bisphosphonate treatment were matched to each patient who had received this treatment preoperatively by gender, age, race, ethnicity, body mass index (BMI), and type of arthroplasty. Previous bisphosphonate treatment was defined as treatment occurring during the three-year period before the arthroplasty. The primary outcome measure was the incidence of intraoperative complications and those occurring at one and two years postoperatively. A total of 87 patients were included: 29 in the bisphosphonates-exposed (BP+) group and 58 in the non-exposed (BP-) group. In the BP+group, there were 26 female and three male patients, with a mean age of 71.4 years (51 to 87). In the BP-group, there were 52 female and six male patients, with a mean age of 72.1 years (53 to 88).ResultsPrevious treatment with bisphosphonates was positively associated with intraoperative complications (fracture; odds ratio (OR) 39.40, 95% confidence interval (CI) 2.42 to 6305.70) and one-year postoperative complications (OR 7.83, 95% CI 1.11 to 128.82), but did not achieve statistical significance for complications two years postoperatively (OR 3.45, 95% CI 0.65 to 25.28). The power was 63% for complications at one year.ConclusionPatients who are treated with bisphosphonates during the three-year period before shoulder arthroplasty have a greater risk of intraoperative and one-year postoperative complications compared with those without this previous treatment.

In this study, the role of shallow convection and its links with planetary boundary layer (PBL) mixing is analyzed using a global atmospheric model. All of the simulations are conducted with the Korean Integrated Model (KIM), which is a next‐generation operational global model for Korea Meteorological Administration. The simulation results show that the direct effect of shallow convection enhances additional vertical mixing inside the shallow convective layer, whereas its indirect effect reduces vertical mixing inside the PBL by changing the PBL height, thus vertical mixing strength. It is also found that the impact of shallow convection on low‐level clouds is tightly related to the overlapping between PBL and shallowing convection. When the PBL height is located in the higher (lower) part of the shallow convective layer, the mixing across the top of the PBL becomes smaller (larger). Therefore, the diffusivity profile of KIM shallow convection scheme is modified according to the overlapping pattern of PBL mixing and shallow convection. The systematic bias of downward solar radiation at the surface of KIM is improved with the revised diffusivity profile of the shallow convection scheme proposed in this study. PBL mixing and shallow convection are tightly linked in modelIntensity of diffusivity profile in shallow convection scheme can modulate cloud amount and radiation budgetNWP performance can conventionally be improved via a modification of shallow convection scheme

Recently, a new set of failure criteria was proposed by the authors (Kwon and Darcy in Multiscale Multidiscip Model Exp Des 1(1):3–17, 2018), which was based on a multiscale modeling technique. The failure criteria used stress and strain values at the constituent material levels. This paper presented the failure criteria in terms of a general framework for any reinforced composite material. The paper also discussed progressive failure modeling of laminated composite structures as local materials fail based on the failure criteria until the ultimate failure of the structure. To further validate the proposed failure modeling technique, experiments were conducted to obtain the failure data of filament-wound composite cylinders subjected to internal pressure loading. The test data were also compared to the numerical predictions.

Record‐breaking melt over Greenland in recent decades is linked not only to climate change but also to natural variability, including persistent atmospheric high‐pressure conditions in the negative phase of the North Atlantic Oscillation and warm North Atlantic Ocean temperatures during the positive phase of the Atlantic Multidecadal Oscillation. However, the relative importance of natural variability for Greenland melt under varying degrees of greenhouse forcing is still unclear. Using reanalysis data and a large ensemble of climate model simulations, we find that a negative North Atlantic Oscillation and positive Atlantic Multidecadal Oscillation consistently promote heightened summer melt under various forcing conditions. Moreover, timing of widespread 21st century Greenland melt varies considerably between ensemble members due to different phasing of these modes of natural variability. These results indicate the importance of natural modes of variability across a range of external forcing conditions for interannual melt variability and the emergence of widespread Greenland melt. Extreme Greenland Ice Sheet melt is partly driven by climate change, as rising greenhouse gas concentrations promote warmer temperatures, especially for the Arctic region. However, natural fluctuations in the climate system can also promote Greenland melt. In particular, persistent high‐pressure systems in the atmosphere over the region and warm North Atlantic Ocean temperatures have been linked to enhanced Greenland melt in recent decades. Yet the importance of these natural oscillations for melt in the past and future remains unclear. We use a series of climate model simulations to show that high‐pressure conditions and a warm North Atlantic Ocean consistently promote heightened summer melt under various warming scenarios for the past and future. Additionally, the timing of widespread Greenland melt in the 21st century depends on the timing of these modes of natural variability. Links between natural variability and Greenland melt are studied under various greenhouse forcings in the Community Earth System ModelA negative summer North Atlantic Oscillation and positive Atlantic Multidecadal Oscillation promote extreme melt in all forcing scenariosThe timing of emergence of widespread 21st century Greenland melt is dependent on the phasing of these modes of natural variability

An experimental study was conducted for the fluid–structure interaction (FSI) of the vibration of a flexible structure inside the channel driven cavity flow (CDCF). The structure was a thin flat plate whose one edge was clamped at the bottom of the three-dimensional CDCF system. Both aluminum and composite plates were examined. Initially the vibrational characteristics of the structures were measured without fluid flow. Subsequently, each structural vibration was measured under various flow rates through the CDCF system. The structural vibration was measured using strain gages attached to the structures as well as non-contact displacement sensors. Time histories of the strains and displacements were obtained, and their time averages and the vibrational magnitudes were computed as a function of the nominal flow rate through the channel cross-section. This set of test data is expected to be useful for validation of a computer program for analyzing a FSI problem.

Dynamic loading can be transferred from one structure to another via fluid media with fluid–structure interaction (FSI). Previous studies demonstrated that FSI played a critical role for polymer composite structures in contact with water because their material densities are very comparable to that of water. This paper studied the structural coupling effect through a fluid medium contained among the structures. This study was an extension of the previous experimental work reported in Kwon and Bowling (Multiscale Multidiscip Model Exp Des 1(1):69–82, 2018). Composite structural stiffness, spacing and the number of coupled structures were varied in the experiments to determine their effects. The experimental results showed that the effects of different parameters on the structural responses of couple structures were quite complex, and they have to be well understood for proper design of coupled structures via a fluid medium.

Bursts of gamma ray showers have been observed in coincidence with downward propagating negative leaders in lightning flashes by the Telescope Array Surface Detector (TASD). The TASD is a 700‐km2cosmic ray observatory located in southwestern Utah, USA. In data collected between 2014 and 2016, correlated observations showing the structure and temporal development of three shower‐producing flashes were obtained with a 3‐D lightning mapping array, and electric field change measurements were obtained for an additional seven flashes, in both cases colocated with the TASD. National Lightning Detection Network information was also used throughout. The showers arrived in a sequence of 2–5 short‐duration (≤10 μs) bursts over time intervals of several hundred microseconds and originated at an altitude of ≃3–5 km above ground level during the first 1–2 ms of downward negative leader breakdown at the beginning of cloud‐to‐ground lightning flashes. The shower footprints, associated waveforms and the effect of atmospheric propagation indicate that the showers consist primarily of downward‐beamed gamma radiation. This has been supported by GEANT simulation studies, which indicate primary source fluxes of ≃1012–1014photons for 16° half‐angle beams. We conclude that the showers are terrestrial gamma ray flashes, similar to those observed by satellites, but that the ground‐based observations are more representative of the temporal source activity and are also more sensitive than satellite observations, which detect only the most powerful terrestrial gamma ray flashes. Gamma ray showers have been detected in a surface scintillator array coincident with lightning observed by a lightning mapping array or Delta EantennaThe showers were produced less than 4–5 km above ground in the first 1–2 ms of downward negative breakdown during cloud‐to‐ground flashesThe source durations are better resolved than for satellite observations and are consistent with being produced by stepping of the initial leader breakdown

A multiscale modeling technique was developed to predict mechanical properties of human bone, which utilizes the hierarchies of human bone in different length scales from nanoscale to macroscale. Bone has a unique structure displaying high stiffness with minimal weight. This is achieved through a hierarchy of complex geometries composed of three major materials: hydroxyapatite, collagen and water. The identifiable hierarchical structures of bone are hydroxyapatite, tropocollagen, fibril, fiber, lamellar layer, trabecular bone, cancellous bone and cortical bone. A helical spring model was used to represent the stiffness of collagen. A unit cell-based micromechanics model computed both the normal and shear stiffness of fibrils, fibers, and lamellar layers. A laminated composite model was applied to cortical and trabecular bone, while a simplified finite element model for the tetrakaidecahedral shape was used to evaluate cancellous bone. Modeling bone from nanoscale components to macroscale structures allows the influence of each structure to be assessed. It was found that the distribution of hydroxyapatite within the tropocollagen matrix at the fibril level influences the macroscale properties significantly. Additionally, the multiscale analysis model can vary any parameter of any hierarchical level to determine its effect on the bone property. With so little known about the detailed structure of nanoscale and microscale bone, a model encompassing the complete hierarchy of bone can be used to help validate assumptions or hypotheses about those structures.

Dynamic analysis was conducted for two flexible composite structures coupled by a fluid medium. As the dynamic loading is applied to one structure, the other structure responds to the dynamic loading resulting from the load transfer through the fluid medium. To investigate such a coupled interaction between two structures, both experimental and numerical studies were conducted to supplement each other. First, a series of experiments were undertaken for two separate composite plates. In the designed test setup, water was filled between two composite plates. The water level between the two plates was varied and strain gages were attached to the composite plates. An impact load was applied to the front composite plate, and the dynamic responses of the both plates were measured using the strain gages. The cellular automata (CA) technique was also used for the numerical study. The results showed that the fluid–structure interaction (FSI) played an important role for the structural coupling depending on the water level between the plates.

AimsThe factors that predispose to recurrent instability and revision stabilization procedures after arthroscopic Bankart repair for anterior glenohumeral instability remain unclear. We sought to determine the rate and risk factors associated with ongoing instability in patients undergoing arthroscopic Bankart repair for instability of the shoulder.Materials and MethodsWe used the Statewide Planning and Research Cooperative System (SPARCS) database to identify patients with a diagnosis of anterior instability of the shoulder undergoing arthroscopic Bankart repair between 2003 and 2011. Patients were followed for a minimum of three years. Baseline demographics and subsequent further surgery to the ipsilateral shoulder were analyzed. Multivariate analysis was used to identify independent risk factors for recurrent instability.ResultsA total of 5719 patients were analyzed. Their mean age was 24.9 years (sd9.3); 4013 (70.2%) were male. A total of 461 (8.1%) underwent a further procedure involving the ipsilateral shoulder at a mean of 31.5 months (sd23.8) postoperatively; 117 (2.1%) had a closed reduction and 344 (6.0%) had further surgery. Revision arthroscopic Bankart repair was the most common subsequent surgical procedure (223; 65.4%). Independent risk factors for recurrent instability were: age < 19 years (odds ratio 1.86), Caucasian ethnicity (hazard ratio 1.42), bilateral instability of the shoulder (hazard ratio 2.17), and a history of closed reduction(s) prior to the initial repair (hazard ratio 2.45). Revision arthroscopic Bankart repair was associated with significantly higher rates of ongoing persistent instability than revision open stabilization (12.4% vs5.1%, p = 0.041).ConclusionThe incidence of a further procedure being required in patients undergoing arthroscopic Bankart repair for anterior glenohumeral instability was 8.1%. Younger age, Caucasian race, bilateral instability, and closed reduction prior to the initial repair were independent risk factors for recurrent instability, while subsequent revision arthroscopic Bankart repair had significantly higher rates of persistent instability than subsequent open revision procedures.Cite this article: Bone Joint J2018;100-B:324–30.

Failure criteria were proposed to describe physics-based failure modes of the fibrous composite at its micro-scale level. The criteria consist of four failure modes at the constituent material level, and they are: fiber breakage, fiber buckling, matrix cracking, and fiber/matrix interface debonding. The failure criteria for these failure modes were expressed in terms of stresses and strains at the micro-scale, i.e., those occurring within the fiber and matrix materials. To determine the micro-scale stresses and strains and to apply the failure criteria to the macro-scale composite material, a multiscale analysis was employed. The multiscale analysis links the micro-scale and macro-scale using the unit cell approach. The unit cell can compute the macro-scale (i.e., effective) material properties from the micro-scale (i.e., constituents) material properties. In addition, the unit cell can also compute micro-scale stresses and strains from macro-scale stresses and strains. The proposed failure criteria can be used for composite structures such as laminated fibrous composites, woven fabric composites, etc., The criteria were applied to multiple example cases under combined loading, which had available experimental data, to assess their reliability. The prediction using the proposed failure criteria agreed well with the experimental data.

In this paper, we present the first high‐speed video observation of a cloud‐to‐ground lightning flash and its associated downward‐directed Terrestrial Gamma‐ray Flash (TGF). The optical emission of the event was observed by a high‐speed video camera running at 40,000 frames per second in conjunction with the Telescope Array Surface Detector, Lightning Mapping Array, interferometer, electric‐field fast antenna, and the National Lightning Detection Network. The cloud‐to‐ground flash associated with the observed TGF was formed by a fast downward leader followed by a very intense return stroke peak current of −154 kA. The TGF occurred while the downward leader was below cloud base, and even when it was halfway in its propagation to ground. The suite of gamma‐ray and lightning instruments, timing resolution, and source proximity offer us detailed information and therefore a unique look at the TGF phenomena. This study provides the very first simultaneous observations of a downward‐directed terrestrial gamma‐ray flash (TGF) together with its associated cloud‐to‐ground lightning flash using a high‐speed camera in addition to gamma‐ray and radio measurements. The camera, running at 40,000 frames per second, allowed us to check the characteristics of the downward leader, the development stage of the lightning flash, and the luminosity variations in coincidence with TGF production. Simultaneous recordings of a downward‐directed terrestrial gamma‐ray flash (TGF), high‐speed video images, and radio emissionsTGF events occurred while the leader was already branching below cloud base and even when it was halfway in its propagation to groundEnergetic downward‐directed TGFs were associated with fast downward leaders that produced high return stroke peak currents Simultaneous recordings of a downward‐directed terrestrial gamma‐ray flash (TGF), high‐speed video images, and radio emissions TGF events occurred while the leader was already branching below cloud base and even when it was halfway in its propagation to ground Energetic downward‐directed TGFs were associated with fast downward leaders that produced high return stroke peak currents

Nod-like receptor family, CARD domain-containing 4 (NLRC4) inflammasome activation is required for efficient clearance of intracellular pathogens through caspsase-1-dependent pyroptosis in macrophages. Although neutrophils have a critical role in protection from Pseudomonas aeruginosainfection, the mechanisms regulating inflammasome-mediated pyroptosis in neutrophils and its physiological role are largely unknown. We sought to determine the specific mechanisms regulating neutrophil pyroptosis in P. aeruginosastrain PAO1 (PAO1) lung infection and to identify the pathological role of this process. Nox2−/−models with reduced neutrophil antibacterial activity exhibited increased neutrophil pyroptosis, which was mediated by flagellin, a pathogenic PAO1 component. We also demonstrate that PAO1-induced pyroptosis depended on NLRC4 and Toll-like receptor 5 (TLR5) in neutrophils generated from Nlrc4−/−or Tlr5−/−mice. Our study reveals previously unknown mechanisms and physiological role of neutrophil pyroptosis during P. aeruginosalung infection. Furthermore, our findings regarding neutrophil pyroptosis in the context of neutrophil dysfunction may explain the causes of acute and/or chronic infectious diseases discovered in immune-compromised patients.

Nod-like receptor family, CARD domain-containing 4 (NLRC4) inflammasome activation is required for efficient clearance of intracellular pathogens through caspsase-1-dependent pyroptosis in macrophages. Although neutrophils have a critical role in protection from Pseudomonas aeruginosa infection, the mechanisms regulating inflammasome-mediated pyroptosis in neutrophils and its physiological role are largely unknown. We sought to determine the specific mechanisms regulating neutrophil pyroptosis in P. aeruginosa strain PAO1 (PAO1) lung infection and to identify the pathological role of this process. Nox2−/−models with reduced neutrophil antibacterial activity exhibited increased neutrophil pyroptosis, which was mediated by flagellin, a pathogenic PAO1 component. We also demonstrate that PAO1-induced pyroptosis depended on NLRC4 and Toll-like receptor 5 (TLR5) in neutrophils generated from Nlrc4−/−or Tlr5−/−mice. Our study reveals previously unknown mechanisms and physiological role of neutrophil pyroptosis during P. aeruginosa lung infection. Furthermore, our findings regarding neutrophil pyroptosis in the context of neutrophil dysfunction may explain the causes of acute and/or chronic infectious diseases discovered in immune-compromised patients.

The electronic structures of the layered rare-earth chalcogenide compounds of CeTe2, PrTe2, and PrTe3, which have the charge-density wave (CDW) transition and possibly the chiral transition, have been investigated by employing soft X-ray absorption spectroscopy (XAS) and angle-resolved photoemission spectroscopy (ARPES). R 3dXAS measurements show that the valence states of Ce and Pr ions are nearly trivalent in all the compounds. Similar band dispersions are observed in their measured ARPES data, but with the band positions in PrTe3being shifted up in energy compared to those in CeTe2and PrTe2. These findings suggest that their Te 5pband structures are determined mainly by the 2D interactions in the Te(2)/Te(3) sheets, but with a larger number of holes in the Te 5pbands in PrTe3than in CeTe2and PrTe2. The measured constant energy maps of CeTe2, PrTe2, and PrTe3for high binding energies are similar to one another, reflecting the Te 5pband structures of the Te(2)/Te(3) square nets. In contrast, the Fermi surfaces (FSs) of CeTe2and PrTe3 exhibit extra features, different from the FS of the ideal Te(2)/Te(3) square nets, which arise from the CDW-induced FS reconstruction in the Te(2)/Te(3) sheets.

The strong sea‐surface temperature (SST) gradient associated with the Gulf Stream (GS) is widely acknowledged to play an important role in shaping mid‐latitude weather and climate. Despite this, an index for the GS SST gradient has not yet been standardized in the literature. This paper introduces a monthly index for the large‐scale SST gradient across the separated GS based on the time‐varying GS position detected from sea‐surface height. Analysis suggests that the variations in the monthly average SST gradient throughout the year result primarily from SST variability to the north of the GS, with little contribution from SST to the south. The index exhibits a weak periodicity at ∼2 years. Sea level pressure and turbulent heat flux patterns suggest that variability in the large‐scale SST gradient is related to atmospheric (rather than oceanic) forcing. Ocean‐to‐atmosphere feedback does not persist throughout the year, but there is some evidence of wintertime feedback. The Gulf Stream is a narrow and fast‐flowing oceanic boundary current that transports warm tropical water north along the coast of Florida and out into the North Atlantic past Cape Hatteras. It is a region where sea‐surface temperatures (SSTs) change dramatically over very short distances with much cooler temperatures on one side of the Gulf Stream (GS) (to the north) and warmer temperatures on the other side (to the south). This strong change in SST across the GS is important for weather systems that propagate in the Euro‐Atlantic sector. Here, an index that measures how much the SSTs change with distance from month‐to‐month across the GS once it separates past Cape Hatteras is developed for the first time. It is found that variability in the index primarily results from SST variations to the north of the separated GS, which themselves are influenced by the atmosphere. There is evidence however that the SST variability represented by the index can also exert an influence on the atmosphere in wintertime. Additionally, the value of the index at any given time seemingly provides some information about the state of the index several years into the future. A monthly index for the large‐scale sea‐surface temperature gradient of the separated Gulf Stream is presentedVariations in the index throughout the year are related to atmospheric forcingEvidence of ocean‐atmosphere feedback in the index is only apparent in wintertime A monthly index for the large‐scale sea‐surface temperature gradient of the separated Gulf Stream is presented Variations in the index throughout the year are related to atmospheric forcing Evidence of ocean‐atmosphere feedback in the index is only apparent in wintertime

The multifunctional enzyme transglutaminase 2 (TG2) primarily catalyzes cross-linking reactions of proteins via (?-glutamyl) lysine bonds. Several recent findings indicate that altered regulation of intracellular TG2 levels affects renal cancer. Elevated TG2 expression is observed in renal cancer. However, the molecular mechanism underlying TG2 degradation is not completely understood. Carboxyl-terminus of Hsp70-interacting protein (CHIP) functions as an ubiquitin E3 ligase. Previous studies reveal that CHIP deficiency mice displayed a reduced life span with accelerated aging in kidney tissues. Here we show that CHIP promotes polyubiquitination of TG2 and its subsequent proteasomal degradation. In addition, TG2 upregulation contributes to enhanced kidney tumorigenesis. Furthermore, CHIP-mediated TG2 downregulation is critical for the suppression of kidney tumor growth and angiogenesis. Notably, our findings are further supported by decreased CHIP expression in human renal cancer tissues and renal cancer cells. The present work reveals that CHIP-mediated TG2 ubiquitination and proteasomal degradation represent a novel regulatory mechanism that controls intracellular TG2 levels. Alterations in this pathway result in TG2 hyperexpression and consequently contribute to renal cancer.

Estrogen receptor alpha (ERa) has a pivotal role in breast carcinogenesis by associating with various cellular factors. Selective expression of additional sex comb-like 2 (ASXL2) in ERa-positive breast cancer cells prompted us to investigate its role in chromatin modification required for ERa activation and breast carcinogenesis. Here, we observed that ASXL2 interacts with ligand E2-bound ERa and mediates ERa activation. Chromatin immunoprecipitation-sequencing analysis supports a positive role of ASXL2 at ERa target gene promoters. ASXL2 forms a complex with histone methylation modifiers including LSD1, UTX and MLL2, which all are recruited to the E2-responsive genes via ASXL2 and regulate methylations at histone H3 lysine 4, 9 and 27. The preferential binding of the PHD finger of ASXL2 to the dimethylated H3 lysine 4 may account for its requirement for ERa activation. On ASXL2 depletion, the proliferative potential of MCF7 cells and tumor size of xenograft mice decreased. Together with our finding on the higher ASXL2 expression in ERa-positive patients, we propose that ASXL2 could be a novel prognostic marker in breast cancer.

ABSTRACTSmall, dark brown leaf spots consistent with symptoms caused by Phomasp. were observed on kiwifruit (Actinidia deliciosacv. Hayward) at an orchard in Sacheon, South Korea. The causal agent was isolated from the spots and identified by morphological and molecular characteristics by sequencing the internal transcribed spacer region. To establish Koch’s postulates, the pathogen was inoculated on to leaves in a pathogenicity test and reisolated from the developed lesions. Phomasp. has been reported as a causal agent of kiwifruit leaf spot disease in New Zealand and Italy. However, this is the first report of leaf spot disease caused by Phomasp. in Korea.

AimsDepression can significantly affect quality of life and is associated with higher rates of medical comorbidities and increased mortality following surgery. Although depression has been linked to poorer outcomes following orthopaedic trauma, total joint arthroplasty and spinal surgery, we wished to examine the impact of depression in elective total shoulder arthroplasty (TSA) as this has not been previously explored. Patients and MethodsThe United States Nationwide Inpatient Sample (NIS) was used to identify patients undergoing elective TSA over a ten-year period. Between 2002 and 2012, 224 060 patients underwent elective TSA.ResultsAmong the identified patients who had undergone TSA, 12.4% had a diagnosis of a history of depression. A diagnosis of depression was twice as common in women compared with men (16.0% vs 8.0%, p < 0.001), and more frequent in those with low income and Medicaid insurance (p < 0.001). A diagnosis of depression was an independent risk factor for post-operative delirium (odds ratio (OR) 2.29, p < 0.001), anaemia (OR 1.65, p < 0.001), infection (2.09, p = 0.045) and hospital discharge to a placement other than home (OR 1.52, p < 0.001) ConclusionA history of clinical depression is present in 12.4% of patients undergoing elective TSA and the disease burden is projected to increase further in the future. Depression is often underdiagnosed and pre-operative screening and appropriate peri-operative management of patients is encouraged.Take home message: The awareness that clinical depression is associated with increased complications following total shoulder arthroplasty provides physicians an opportunity for early intervention in this at-risk population.Cite this article: Bone Joint J2016;98-B:818–24.

AimsThere are many guidelines that help direct the management of patients with metal-on-metal (MOM) hip arthroplasties. We have undertaken a study to compare the management of patients with MOM hip arthroplasties in different countries. MethodsSix international tertiary referral orthopaedic centres were invited to participate by organising a multi-disciplinary team (MDT) meeting, consisting of two or more revision hip arthroplasty surgeons and a musculoskeletal radiologist. A full clinical dataset including history, blood tests and imaging for ten patients was sent to each unit, for discussion and treatment planning. Differences in the interpretation of findings, management decisions and rationale for decisions were compared using quantitative and qualitative methods.ResultsOverall agreement between the orthopaedic centres and the recommended treatment plans for the ten patients with MOM hip implants was moderate (kappa = 0.6). Full agreement was seen in a third of cases, however split decisions were also seen in a third of cases. Units differed in their interpretation of the significance of the investigation findings and put varying emphasis on serial changes, in the presence of symptoms.DiscussionIn conclusion, the management of raised or rising blood metal ions, cystic pseudotumours and peri-acetabular osteolysis led to inconsistency in the agreement between centres. Coordinated international guidance and MDT panel discussions are recommended to improve consensus in decision making.Take home message: A lack of evidence and the subsequent variation in regulator guidance leads to differences in opinions, the clinical impact of which can be reduced through a multi-disciplinary team approach to managing patients with MOM hip implants.Cite this article: Bone Joint J2016;98-B:179–86.

Udenafil is a selective phosphodiesterase type 5 inhibitor made available in recent years for the treatment of erectile dysfunction. Herein, we evaluated independent predictors of potency recovery in radical prostatectomy (RP) patients who underwent penile rehabilitation with udenafil 50?mg. One hundred and forty-three men who underwent RP were enrolled in a penile rehabilitation program using udenafil 50?mg every other day. The rate of regained potency in the study group was significantly higher compared with the recovery rate seen in patients who were not part of the penile rehabilitation program (41.3% vs 13.0%; P<0.001). On the multivariate Cox analyses, preoperative International Index of Erectile Function-5 scores (hazard ratio (HR), 1.049; P=0.040), alcohol consumption (HR, 2.043; P=0.020) and Gleason biopsy score (HR, 0.368; P=0.024) were independent preoperative predictors for potency recovery. Among post-RP variables, the use of robotic procedures (HR, 2.287; P=0.030) and pathologic stage (HR, 0.506; P=0.038) were significantly associated with potency recovery. This study identified predictive factors for the recovery of potency in patients undergoing penile rehabilitation with udenafil following RP. Our results could provide physicians with useful information for counseling RP patients and selecting optimal candidates for penile rehabilitation.

Recently, new failure criteria were proposed for brittle materials to predict their failure loads regardless of the shapes of a notch or a crack in the material. This paper is to further evaluate the failure criteria for different shapes of notches and different materials. A circular hole, elliptical hole, or crack-like slit with a different angle with respect to the loading direction were considered. Double circular holes were also studied. The materials studied were an isotropic material such as polymethyl methacrylate (PMMA) as well as laminated carbon fiber composites. Both cross-ply and quasi-isotropic layup orientations were examined. The lamination theory was used for the composite materials so that they can be modeled as an anisotropic and homogeneous material. The test results were compared to the theoretical predictions using the finite element analysis with two-dimensional plane stress models. Both theoretical failure stresses agreed well with the experimental data for the materials and notch geometries studied herein.

We present a search for the rare leptonic decays B+ → e+νe and B+ → µ+νµ, using the full ϒ(4S) data sample of 772 × 106 BB pairs collected with the Belle detector at the KEKB asymmetric-energy e+e- collider. One of the B mesons from the ϒ(4S) → BB decay is fully reconstructed in a hadronic mode, while the recoiling side is analyzed for the signal decay. We find no evidence of a signal in any of the decay modes. Upper limits of the corresponding branching fractions are determined as B(B+ → e+νe)< 3.5 × 10-6 and B(B+ → µ+νµ)<2.7×10-6 at 90% confidence level. [ABSTRACT FROM AUTHOR]

Polyplexes, complexed nucleic acids by cationic polymers, are the most common forms of nonviral gene delivery vectors. In contrast to a great deal of efforts in synthesizing novel cationic polymers and exploring their extracellular and intracellular delivery pathways, polyplex preparation methods of mixing nucleic acids and cationic polymers are often overlooked. In this study, the mixing sequence, that is adding nucleic acids to polymers or vice versa, was found to greatly affect complexation of both plasmid DNA and siRNA, polyplexes’ size, and polyplexes’ surface charge, which all collaboratively affected the transfection efficiency and cytotoxicity. Adding polyethylenimine (PEI), the most conventionally used standard in nonviral gene delivery, to plasmid DNA and siRNA resulted in larger polyplexes, higher gene expression and silencing, but higher cytotoxicity than polyplexes prepared in the reverse order. Based on the experimental results, the authors developed a model that gradual addition of cationic polymers (e.g., PEI) to nucleic acids (e.g., plasmid DNA and siRNA) incorporates more copies of nucleic acids in larger polyplexes in a smaller number, results in higher gene expression and silencing levels in transfected cells, and generates higher cytotoxicity by leaving more free polymers upon complete mixing than the other mixing sequence. The proposed model can be explored using a broad range of cationic polymers and nucleic acids, and provide insightful information about how to prepare polyplexed nonviral vectors for efficient and safe gene delivery.

The PHENIX MPC-EX is an W/Si pre-shower detector operating at small angles with respect to the beam in the Relativistic Heavy Ion Collider (RHIC). The Si Mini-Pad sensors are the active element of the detector. The expected hadron flux to the Si Mini-Pad sensors will generate significant non-ionizing energy loss in the sensors, which may damage the crystalline structure of the sensor’s bulk material. We investigated the nature of the hadron flux to the Si Mini-Pad sensors through a full simulation and determined its effect on the sensor’s characteristics based on a beam test. The investigation showed key issues in designing a preshower detector using silicon sensors and operating under a large neutron fluence and offered valuable information on the operation of the MPC-EX detector.

The Si Mini-Pad sensor is an essential component of the MPC-EX preshower detector. This detector will be integrated into the PHENIX experiment at Brookhaven National Laboratory’s Relativistic Heavy Ion Collider. We describe the development of the surface pattern and the fabrication process of the Si Mini-Pad sensor and present a test by the low energy γ irradiation that is sensitive to the surface design.

Thermal diffusivity measurements have been used to study the magnetic phase transitions in ZnO doped with Mn. The temperature dependencies of the thermal diffusivity in the wide temperature range from 70 to 300 K reveal an inverted-lambda-shaped peak at a temperature of 75 K for Zn0.95Mn0.05O doped with nitrogen and additional peaks at 117 K and 122 K for the nitrogen-doped and the undoped Zn0.95Mn0.05O samples, respectively. The lambda-shaped peak demonstrates the existence of a second order phase transition in these samples. The thermal diffusivity peak at 75 K was attributed to a ferromagnetic-paramagnetic phase transition in the Zn0.95Mn0.05O doped with nitrogen, and the peaks at 117 K and 122 K were attributed to an antiferromagnetic-paramagnetic phase transition in the MnO nanoclusters.