Correct Location Research Articles

Translational Tomography with the Wide-field Imager for Parker Solar Probe (WISPR). II. Refinements to the Method

We present progress on the translational tomography technique for measuring the three-dimensional structure of the corona from near-perihelion Wide-field Imager for Parker Solar Probe (WISPR) image sequences. Translational tomography makes use of noncircular motion of a camera to extract three-dimensional information from an optically thin subject. Parker Solar Probe (PSP) presents a special case both because of the particular structure of the corona and because of the nonlinear motion of the vantage point. We show improvements to a previous direct analytic method (described in Paper I of this series) and an alternative inversion pathway using a synthetic sequence of WISPR images. The newer method successfully reconstructs the correct locations of modeled coronal rays in a synthetic WISPR image sequence, with curvilinear camera motion modeled on the PSP orbit. We present the refined methodology and validation study, and show that the technique is ready for application to actual WISPR data.

Investigation of Radiation Exposure of Medical Staff During Lateral Fluoroscopy for Posterior Spinal Fusion Surgery

Background/Objectives: In spinal surgery, it is especially crucial to insert implants in the correct location. Intraoperative fluoroscopy is often necessary to safely perform spinal surgery because of serious complications that can occur if the screw deviates. However, the use of intraoperative fluoroscopy comes at the cost of radiation exposure to the surgeons and operating room staff. Therefore, it is desirable for spinal surgeons to understand the characteristics of radiation in order to minimize patient and medical staff exposure. This study aimed to create an aerial radiation dose distribution map for lateral fluoroscopy, a commonly used technique for posterior spinal fusion. Methods: A human body-equivalent phantom was placed in a prone position on the Jackson Table. The measurement method used was a lateral fluoroscopic evaluation, assuming posterior spinal fusion. Measurements were taken at three levels: 80 (gonadal), 100 (thoracoabdominal), and 150 cm (lens and thyroid). Results: The highest radiation doses were received by primary surgeons. The scrub nurse was the next most exposed. Conclusions: We developed an aerial dose distribution map for lateral fluoroscopy in posterior spinal fusion. Radiation exposure was the highest among primary surgeons.

Infants Produce Optimally Informative Points to Satisfy the Epistemic Needs of Their Communicative Partner.

Pragmatic theories assume that during communicative exchanges humans strive to be optimally informative and spontaneously adjust their communicative signals to satisfy their addressee's inferred epistemic needs. For instance, when necessary, adults flexibly and appropriately modify their communicative gestures to provide their partner the relevant information she lacks about the situation. To investigate this ability in infants, we designed a cooperative task in which 18-month-olds were asked to point at the target object they wanted to receive. In Experiment 1, we found that when their desired object was placed behind a distractor object, infants appropriately modified their prototypical pointing to avoid mistakenly indicating the distractor to their partner. When the objects were covered, and their cooperative partner had no information (Experiment 2) or incorrect information (Experiment 3) about the target's location - as opposed to being knowledgeable about it - infants pointed differentially more often at the target and employed modified pointing gestures more frequently as a function of the amount of relevant information that their partner needed to retrieve their desired object from its correct location. These findings demonstrate that when responding to a verbal request in a cooperative task 18-month-old infants can take into account their communicative partner's epistemic states and when necessary provide her with the relevant information she lacks through sufficiently informative deictic gestures. Our results indicate that infants possess an early emerging, species-unique cognitive adaptation specialized for communicative mindreading and pragmatic inferential communication which enable the efficient exchange of relevant information between communicating social partners in cooperative contexts.

Striking the right note: balancing AVAS in tomorrow's soundscapes

Soundscapes of tomorrow are defined now. Not just a mobile sonic brand signature, the AVAS is also an attention grabber and an imposed alert. The method invoked for its design must be collaborative and involve the brand, designers, marketers, stakeholders, but also drivers, residents and question its position in the soundscape. Defining the aesthetic with a shared semantic, listening, testing, in simulation, on road, with people, with sensors; any sound design should be the result of a collaborative process because it talks to people, improve the perceived quality of products, and improve the quality of life. If well made. Also AVAS sound is also regulated by international standards that are defining boundaries in the selection of the right sound. The signal emitted by the AVAS loudspeaker should follow these rules, in terms of minimum level and spectrum content at specific pedestrians' locations around the car. The simulation of the propagation of the sound from the loudspeaker to these positions in early phase of the design is important to avoid big design mistake. 3D acoustic simulations using FE acoustic software Actran and dedicated post-processing for AVAS are performed to confirm the correct location of loudspeaker and spectral content.

Centromeres in cancer: Unraveling the link between chromosomal instability and tumorigenesis.

Centromeres are critical structures involved in chromosome segregation, maintaining genomic stability, and facilitating the accurate transmission of genetic information. They are key in coordinating the assembly and help keep the correct structure, location, and function of the kinetochore, a proteinaceous structure vital for ensuring proper chromosome segregation during cell division. Abnormalities in centromere structure can lead to aneuploidy or chromosomal instability, which have been implicated in various diseases, including cancer. Accordingly, abnormalities in centromeres, such as structural rearrangements and dysregulation of centromere-associated proteins, disrupt gene function, leading to uncontrolled cell growth and tumor progression. For instance, altered expression of CENP-A, CENP-E, and others such as BUB1, BUBR1, MAD1, and INCENP, have been shown to ascribe to centromere over-amplification, chromosome missegregation, aneuploidy, and chromosomal instability; this, in turn, can culminate in tumor progression. These centromere abnormalities also promoted tumor heterogeneity by generating genetically diverse cell populations within tumors. Advanced techniques like fluorescence in situ hybridization (FISH) and chromosomal microarray analysis are crucial for detecting centromere abnormalities, enabling accurate cancer classification and tailored treatment strategies. Researchers are exploring strategies to disrupt centromere-associated proteins for targeted cancer therapies. Thus, this review explores centromere abnormalities in cancer, their molecular mechanisms, diagnostic implications, and therapeutic targeting. It aims to advance our understanding of centromeres' role in cancer and develop advanced diagnostic tools and targeted therapies for improved cancer management and treatment.

Anatomical validation of needle placement for cervical paraspinal mapping of the multifidus.

The paraspinal muscles are an important component of electrodiagnostic testing for radiculopathy. In the cervical region, a protocol for cervical paraspinal mapping assumes accurate placement of the electromyography (EMG) needle into the cervical multifidus. However, there is scant information regarding the accuracy of needle placement in that muscle. This study examines the accuracy of this protocol in sampling the intended multifidus muscle of cadavers. An experienced electromyographer directed needles to multifidus at C5, C7, and T2 spinous processes of 19 embalmed cadavers, and injected color dyes. Separately another examiner dissected the cadavers, noting whether the dye was in the correct location and whether its trajectory approached any "danger zones" of nerve, artery, or joint. The dye was in the multifidus muscle 100% of the time and hit the intended bony target in 79%, 73%, and 79% of C5, C7, and T2 insertions. No insertion was found in a danger zone. The results indicate modest accuracy for EMG needle placement as proposed in the clinical protocol. Clinical utility of this method requires more work including the establishment of norms, sensitivities, specificities, and clinical impact.

MRNA localization and thylakoid protein biogenesis in the filamentous heterocyst-forming cyanobacterium Anabaena sp. PCC 7120.

Heterocyst-forming cyanobacteria such as Anabaena (Nostoc) sp. PCC 7120 exhibit extensive remodeling of their thylakoid membranes during heterocyst differentiation. Here we investigate the sites of translation of thylakoid membrane proteins in Anabaena vegetative cells and developing heterocysts, using mRNA fluorescent in situ hybridization (FISH) to detect the location of specific mRNA species. We probed mRNAs encoding reaction center core components and the heterocyst-specific terminal oxidases Cox2 and Cox3. As in unicellular cyanobacteria, the mRNAs encoding membrane-integral thylakoid proteins are concentrated in patches at the inner face of the thylakoid membrane system, adjacent to the central cytoplasm. These patches mark the putative sites of translation and membrane insertion of these proteins. Oxidase activity in mature heterocysts is concentrated in the specialized "honeycomb" regions of the thylakoid membranes close to the cell poles. However, cox2 and cox3 mRNAs remain evenly distributed over the inner face of the thylakoids, implying that oxidase proteins migrate extensively after translation to reach their destination in the honeycomb membranes. The RNA-binding protein RbpG is the closest Anabaena homolog of Rbp3 in the unicellular cyanobacterium Synechocystis sp. PCC 6803, which we previously showed to be crucial for the correct location of photosynthetic mRNAs. An rbpG null mutant shows decreased cellular levels of photosynthetic mRNAs and photosynthetic complexes, coupled with perturbations to thylakoid membrane organization and lower efficiency of the Photosystem II repair cycle. This suggests that the chaperoning of photosynthetic mRNAs by RbpG is important for the correct coordination of thylakoid protein translation and assembly.IMPORTANCECyanobacteria have a complex thylakoid membrane system which is the site of the photosynthetic light reactions as well as most of the respiratory activity in the cell. Protein targeting to the thylakoids and the spatial organization of thylakoid protein biogenesis remain poorly understood. Further complexity is found in some filamentous cyanobacteria that produce heterocysts, specialized nitrogen-fixing cells in which the thylakoid membranes undergo extensive remodeling. Here we probe mRNA locations to reveal thylakoid translation sites in a heterocyst-forming cyanobacterium. We identify an RNA-binding protein important for the correct co-ordination of thylakoid protein translation and assembly, and we demonstrate the effectiveness of mRNA fluorescent in situ hybridization (FISH) as a way to probe cell-specific gene expression in multicellular cyanobacteria.

Pulsatile Drug Delivery System: A Review

As modern technologies advance, new methods of drug delivery systems are constantly being developed. Pulsatile drug delivery system is becoming increasingly popular because it can deliver the drug at the correct location, time, and dosage, improving patient adherence. These technologies are designed to align with the body's inherent circadian rhythm. Pulsatile drug release is mainly preferred when continuous drug release is not needed. Understanding the circadian clock's design, illness rhythm pathophysiology, and chrono pharmacology’s medication knowledge helps create and utilize chronotherapeutic dosage forms for effective disease treatment, reducing side effects, improving targeted drug delivery, and maintaining consistent dosing. Proper design of pulsatile drug delivery enhances patient adherence, targets drug distribution, and decreases side effects. Like many other medical conditions, the outlook for chronotherapy using pulsatile drug delivery seems very optimistic. Pulsatile drug delivery systems can utilize either one or multiple mechanisms to administer medication at a specific time and location. Formulation of pulsatile flow is achieved by incorporating different polymers, with the thickness of the coating layer dictating the speed of release of the active medicinal ingredient.

Rational frequency range and criteria for diagnosing endogenous fire zones in coal massifs by using the georadiolocation method

Relevance. The necessity to improve the accuracy of analysis and prediction of potential fire hazard of rock-coal massifs by using electromagnetic methods of endogenous fire detection. Taking into consideration that the increase in coal temperature changes a number of its parameters, such as dielectric permittivity and electrical resistivity, it is reasonable to use the method of electromagnetic reconnaissance in locating the focus of fire. Aim. To analyze the theoretical and practical knowledge about the anomalies formed in the area of spontaneous combustion and to evaluate the effectiveness of electromagnetic methods for locating the spontaneous combustion zones of a coal massif. Objects. Physical parameters of the ignition zone of the coal massif, such as dielectric permittivity and electrical resistivity, as well as the range of the GPR central frequency, allowing clearly defining the boundaries of the ignited zone. Method. Reviewing the proposed methods of determining the parameters serving for correct location of the fire zone. For GPR it is necessary to determine the center frequency of the standard antenna unit and resolution, then to estimate the rational frequency range of GPR. Results. Allow us to draw conclusions about the methods used to determine the rational range of GPR center frequency – it can be calculated by solving the system of equations of the signal attenuation function and energy potential of GPR, by the experimental value of the target function, including the depth and detail of sounding as a function of frequency, or on the basis of a complex parameter of GPR, including the radiated power of the antenna, the number of accumulations and the reflection coefficient from the boundaries. Taking into account such physical features of the fire zone as drying the rock-angle massif and the shape of the anomalous zone, the rational range of the center frequency for the GPR "OKO-2" was determined.

Ants (Lasius niger) deposit more pheromone close to food sources and further from the nest but do not attempt to update erroneous pheromone trails

Many social insects use pheromone trails to recruit workers to resources. Pheromone trails have some limitations, however. Two major limitations are that they evaporate over time, meaning that more distant locations may be more difficult to recruit precisely to, and that they cannot be removed if laid erroneously, or if they become outdated. Here, we ask whether Lasius niger ants can adaptively modulate pheromone deposition to overcome these limitations. Specifically, we first ask whether ants which have followed a pheromone trail to a wrong (unrewarded) location upregulate pheromone deposition to the correct food location to compete with the erroneous trail. They do not. Then, we examine how food distance and proximity to food influence pheromone deposition. We find that ants deposit up to 22 times more pheromone within 10 cm of a food source compared to when they are about to reach the nest. Moreover, they deposit up to four times more pheromone next to a food source placed 100 cm away from the nest as compared to one placed 20 cm away from the nest. Lasius niger ants thus do not display a mechanism for overcoming outdated or erroneously-laid trails by strengthening correct alternatives in our experiment, but do strongly upregulate recruitment to more distant food sources, which are more difficult to locate and recruit to.

Validation of the implementation of phased-array heating systems in Plan2Heat.

Hyperthermia treatment planning can be supportive to ensure treatment quality, provided reliable prediction of the heating characteristics (i.e., focus size and effects of phase-amplitude and frequency steering) of the device concerned is possible. This study validates the predictions made by the treatment planning system Plan2Heat for various clinically used phased-array systems. The evaluated heating systems were AMC-2, AMC-4/ALBA-4D (Med-Logix srl, Rome, Italy), BSD Sigma-30, and Sigma-60 (Pyrexar Medical, Salt Lake City, UT, USA). Plan2Heat was used for specific absorption rate (SAR) simulations in phantoms representing measurement set-ups reported in the literature. SAR profiles from published measurement data based on E‑field or temperature rise were used to compare the device-specific heating characteristics predicted by Plan2Heat. Plan2Heat is able to predict the correct location and size of the SAR focus, as determined by phase-amplitude settings and operating frequency. Measured effects of phase-amplitude steering on focus shifts (i.e., local SAR minima or maxima) were also correctly reflected in treatment planning predictions. Deviations between measurements and simulations were typically < 10-20%, which is within the range of experimental uncertainty for such phased-array measurements. Plan2Heat is capable of adequately predicting the heating characteristics of the AMC‑2, AMC-4/ALBA-4D, BSD Sigma-30, and Sigma-60 phased-array systems routinely used in clinical hyperthermia.

Pure quasi-P-wave modeling and imaging using an approximated space-domain pseudo-differential operator in vertical transverse isotropy media

Incorporating anisotropy in seismic modeling and imaging is important to produce the correct locations of subsurface reflectors. Traditional wave equations for quasi-P-wave in transverse isotropic media either suffer from S-wave artifacts or require complicated and expensive computation strategies. To mitigate this issue, we develop a novel pure quasi-P-wave equation with an approximated space-domain pseudo-differential operator in the vertical transverse isotropic (VTI) medium. For the pure quasi-P-wave equation, we first simplify it to an elliptical anisotropy equation with an additional pseudo-differential correction term. Then, we directly approximate the pseudo-differential term with a space-domain convolution operator that is calculated by solving a nonlinear inverse problem. Phase-velocity analysis and numerical modeling show that the new space-domain pseudo-differential operator has good accuracy in describing wave propagation in the VTI medium. In addition, it is more suitable for parallel computation with domain-decomposition than the Fourier transform, which is necessary for solving traditional pseudo-differential operators. Finally, we apply our quasi-P-wave propagator to reverse time migration to correct the anisotropic effects in seismic imaging. Numerical experiments for the benchmark models and a land survey demonstrate the feasibility and adaptability of our method.

A survey for the use of torque-limiting devices among dental clinicians in Europe.

To assess how well torque-limiting devices (TLDs) are known and used by European dentists, and their adherence to screw tightening protocols and screw loosening occurrence through a survey, including the correlation between the dental specialty-of-interest and the recognition, the tightening protocol used, and between the calibration and the occurrence of screw loosening. A 10-question survey was distributed to dentists to collect data on their specialty-of-interest, TLD usage, knowledge on TLDs, calibration, the term "preload," tightening speed, tightening protocols used, and occurrence of screw loosening. Pearson test was used for correlation analysis between the specialty-of-interest and the recognition-based questions, the tightening protocol used, and between the calibration and the frequency of screw loosening. Of 422 respondents, 24% calibrated their TLDs, 27% knew the term "preload," 76% selected the correct location to read on TLDs, and 6% was aware of the effect of tightening speed. The correlation between the specialty-of-interest and the recognition-based questions was nonsignificant (p < .05) but was significant for used tightening protocol (p < .001). The correlation between the calibration and the occurrence of screw loosening was nonsignificant (p = 0.16). Tightening protocols' effect on screw loosening was similar, which was mostly observed less than once a year (p < .001). A lack in dentists' knowledge was found on calibration, the term preload, and the effect of tightening speed, which were not impacted by the dentists' specialty-of-interest, which affected the preferred tightening protocol. The tightening protocol and calibration did not impact the occurrence of screw loosening, which was mostly observed less than once a year.

Arterial Oxygen Desaturation Hinders Gamified Working Memory Performance.

Hypoxia presents a physiological challenge to the Warfighters during military aviation and subterranean warfare operations by decreasing the supply of oxygen to the brain, which results in a reduced cognitive function depending on the magnitude and duration of hypoxic exposure. Moderate hypoxic exposures, fractions of inspired oxygen (FiO2) of 0.11 to 0.14, show no effects on simple tasks, but complex tasks like working memory may be hindered. Unfortunately, people often cannot recognize their own symptoms of hypoxemia, which are individualistic at moderate hypoxic exposure. Thus, screening tools, like gamified cognitive assessments, during moderate hypoxia may provide personnel objective feedback to initiate safety protocols before a possible accident. However, whether gamified assessments of working memory are sensitive to moderate hypoxia is unknown. Therefore, we tested the hypothesis which moderate normobaric hypoxia decreases gamified working memory performance when accounting for the individualistic responses of arterial blood oxygen saturations. Following 3 consecutive days of 2 practice sessions per day, 30 healthy adults (25 ± 5 years, 10 women) completed three 1-min rounds of the tablet-based working memory game (Backtracker, Statespace Labs, Inc.) at baseline and 60 and 90 min after exposure to FiO2 (= 0.138 ± 0.002 [hypoxia] and 0.201± 0.004 [normoxia] oxygen). Both conditions were completed on the same day and administered in a single-blind, block randomized manner. Arterial oxyhemoglobin saturation was estimated via forehead pulse oximetry (SpO2). Data were analyzed using linear mixed effects modeling. Compared to normoxia (99 ± 1%), SpO2 was lower (P < .001) at 60 (90 ± 2%) and 90 (90 ± 2%) min of hypoxia. A decrease in SpO2 was associated with a statistically significant decrease in the proportion of both tiles with the correct location (P < .02; -0.016) and correct order of appearance recalled (P < .01; -0.016). A decrease in SpO2 was associated with a statistically significant decrease in median time to first tap (P < .01; -0.041s) and median time between taps (P<.01; -0.030s). A significant interaction effect between the SpO2 decrease and baseline performance was found for proportion of tiles with the correct location recalled (P < .05; -0.014), median time to first tap (P <.01; -0.070s), and median time between taps (P < .01; -0.037s). A significant interaction effect between the SpO2 decrease and the path length was found for the proportion of tiles with the correct location recalled (P < .01; +0.021), median time to first tap (P < .01; -0.036s), and median time between taps (P < .01; -0.043s). These findings indicate that greater decreases in SpO2 during moderate hypoxic exposure hinder performance on a gamified assessment of working memory as measured by the proportion of correctly identified order and location of tiles. Considering the statistically significant decrease in both median time to first tap and median time between taps associated with the decrease in SpO2, participants are taking less time to plan or execute movements, which may compound or independently contribute to spatial and temporal memory mistakes.

Determination of Suitable Beekeeping Places in Sinop Province (Türkiye) By Weighted Overlay Analysis

Bees and beekeeping activities are very important for the sustainability of natural life. Beekeeping has become one of the main sources of income of our country due to products such as pollen, royal jelly, honey and wax obtained from beekeeping activities. In addition, our country's rich geography, climate and topography are very suitable for beekeeping activities. Interest in beekeeping activities has increased because it does not require large areas and costs, requires less maintenance than other agricultural activities, and has high income. With the increasing interest, conscious beekeeping, increasing the efficiency obtained from beekeeping activities and therefore determining suitable beekeeping places have gained importance. For this purpose, a study was carried out to determine suitable places for beekeeping in Sinop province, which is suitable for beekeeping activities due to its flora, climate and location. ArcGIS 10.7.1 program was used to determine suitable areas and weighted overlay analysis was performed using criteria such as slope, aspect, elevation, precipitation, vegetation, and distance to roads, streams and settlements. As a result of the analysis, it was determined that 96.38% of Sinop province was suitable for beekeeping. Additionally, it was checked whether the existing beekeeping sites were in suitable locations, and as a result, it was observed that approximately half of the beekeepers were in the correct locations.

Approaches to supratentorial brain tumours in children.

The differential diagnosis of supratentorial brain tumours in children can be challenging, especially considering the recent changes to the WHO classification of CNS tumours published in 2021. Many new tumour types have been proposed which frequently present in children and young adults and their imaging features are currently being described by the neuroradiology community.The purpose of this article is to provide guidance to residents and fellows new to the field of paediatric neuroradiology on how to evaluate an MRI of a patient with a newly diagnosed supratentorial tumour. Six different approaches are discussed including: 1. Tumour types, briefly discussing the main changes to the recent WHO classification of CNS tumours, 2. Patient age and its influence on incidence rates of specific tumour types, 3. Growth patterns, 4. Tumour location and how defining the correct location helps in narrowing down the differential diagnoses and 5. Imaging features of the tumour on DWI, SWI, FLAIR and post contrast sequences.

Combination of Matrix and Genetic Algorithms for Fault Location of Active Distribution Network

Abstract Timely and effective location of faults in distribution networks is important for restoring power supply and dealing with faults. In this paper, a method combining matrix algorithm and genetic algorithm (GA) is proposed to determine the fault section. Firstly, the matrix algorithm is applied to locate the fault section initially by combining the alarm information uploaded from the feeder terminal unit (FTU). Secondly, in order to deal with the problem of outputting wrong location results, the switching function of the active distribution network is constructed to check the location results calculated by the matrix, and the results that do not meet the checking will be treated as a suspicious fault set, and the relevant evaluation function is constructed and optimized using the genetic algorithm, so as to arrive at the correct fault zone location results. The results of the example simulation show that the method used in this paper can achieve fast and fault-tolerant fault location in active distribution networks.

Subseasonal Forecast Skill of Evaporative Demand, Soil Moisture, and Flash Drought Onset from Two Dynamic Models over the Contiguous United States

Abstract Flash droughts are rapidly developing subseasonal climate extreme events that are manifested as suddenly decreased soil moisture, driven by increased evaporative demand and/or sustained precipitation deficits. Over each climate region in the contiguous United States (CONUS), we evaluated the forecast skill of weekly root-zone soil moisture (RZSM), evaporative demand (ETo), and relevant flash drought (FD) indices derived from two dynamic models [Goddard Earth Observing System model V2p1 (GEOS-V2p1) and Global Ensemble Forecast System version 12 (GEFSv12)] in the Subseasonal Experiment (SubX) project between years 2000 and 2019 against three reference datasets: Modern-Era Retrospective Analysis for Research and Applications version 2 (MERRA-2), North American Land Data Assimilation System, phase 2 (NLDAS-2), and GEFSv12 reanalysis. The ETo and its forcing variables at lead week 1 have moderate-to-high anomaly correlation coefficient (ACC) skill (∼0.70–0.95) except downwelling shortwave radiation, and by weeks 3–4, predictability was low for all forcing variables (ACC &lt; 0.5). RZSM (0–100 cm) for model GEFSv12 showed high skill at lead week 1 (∼0.7–0.85 ACC) in the High Plains, West, Midwest, and South CONUS regions when evaluated against GEFSv12 reanalysis but lower skill against MERRA-2 and NLDAS-2 and ACC skill are still close to 0.5 for lead weeks 3–4, better than ETo forecasts. GEFSv12 analysis has not been evaluated against in situ observations and has substantial RZSM anomaly differences when compared to NLDAS-2, and our analysis identified GEFSv12 reforecast prediction limit, which can maximally achieve ACC ∼0.6 for RZSM forecasts between lead weeks 3 and 4. Analysis of major FD events reveals that GEFSv12 reforecast inconsistently captured the correct location of atmospheric and RZSM anomalies contributing to FD onset, suggesting the needs for improving the dynamic models’ assimilation and initialization procedures to improve subseasonal FD predictability. Significance Statement Flash droughts are rapidly developing climate extremes which reduce soil moisture through enhanced evaporative demand and precipitation deficits, and these events can have large impacts on the ecosystem and crop health. We evaluated the subseasonal forecast skill of soil moisture and evaporative demand against three reanalysis datasets and found that evaporative demand skill was similar between forecasts and reanalyses while soil moisture skill is dependent on the reference dataset. Skill of evaporative demand decreases rapidly after week 1, while soil moisture skill declines more slowly after week 1. Case studies for the 2012, 2017, and 2019 United States flash droughts identified that forecasts could capture rapid decreases in soil moisture in some regions but not consistently, implying that long-lead forecasts still need improvements before being used in early warning systems. Improvements in flash drought predictability at longer lead times will require less biased initial conditions, better model parameterizations, and improved representations of large-scale teleconnections.

The micromechanics of fracture of zirconium hydrides

Zirconium alloys are susceptible to hydrogen embrittlement and hydride precipitation. The precipitation of hydrides is accompanied by a transformation strain, but the contribution of this strain to the fracture of hydrides is not well-understood. In this study, deformation mechanisms and the micromechanics of fracture of hydrides are investigated by conducting in-situ and interrupted ex-situ tensile experiments on hydrided zirconium specimens. Electron backscatter diffraction (EBSD) is used to measure the macro-EBSD maps that contain the grains located in the gauge section of the specimens’ surfaces. Further, high spatial resolution EBSD is used to determine orientation variations induced by the precipitation of hydrides and by the external mechanical load. The measured grain orientations are mapped into a crystal plasticity finite element (CPFE) model to examine the performance of eight different crack initiation criteria. It is shown that a multiscale approach is essential for studying the fracture of hydrides as the details of hydride morphology, orientation, local grain neighborhood, and hydride-hydride interactions are important in such analysis. It is shown that neglecting the effects of hydride-induced transformation strain leads to inaccuracies in predicting both the location and direction of microcracks within hydrides. Among the examined methods, the combination of resolved shear stress and resolved shear strain on slip systems, i.e., the highest shear energy density, consistently predicts the correct locations of hydride microcracks as well as their propagation direction. Further, it is shown that the significant deformation that takes place within hydrides is the main driving force for the fracture of hydrides.

Good practices on transit operation design: bus drivers’ perspective

Understanding which aspects can have the greatest influence on the performance, comfort and safety of a public transport system can be of great help in improving its operation and promoting more sustainable mobility. To find out more about these aspects, a survey was carried out among more than 180 drivers of urban bus transport systems in seven medium-sized cities in Spain. The drivers' perspective has been insufficiently taken into account in previous research, despite the fact that these workers have a high and direct knowledge of the operation and problems directly affecting the service. The data collected through this survey have been analysed using descriptive statistics and an Ordered Probit model. The results have allowed us to detect specific aspects to improve the performance and comfort of users and drivers such as the correct location and length of bus stops and enforcing regulation to ensure that buses have priority in traffic and that illegal parking does not interfere with their operations. In addition, bus lanes were seen as important by drivers to improve the comfort and safety of the service. Other factors related to safety were generally highly rated and there was little dispersion in the responses about their importance, although aspects such as proper visibility, avoiding illegal parking, and campaigns to encourage bus users to be aware of their surroundings stood out in the answers. Finally, the payment system was highlighted as very relevant to ensure the performance and comfort of users and drivers during the operation at bus stops. Improving this system was identified as the measure that could have the greatest impact on the performance of the service as a whole.