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Task-specific focal dystonia (TSFD), characterized by the loss of fine motor control and coordination, affects drummers' lower-limb movements. This study explores lower-limb dystonia's impact on drumming performance and underlying muscle activity in a professional rock drummer. The drummer executed an eight-beat pattern on a drum kit. The participant reported the occurrence of symptoms when he felt the abnormality such as the loss of control related to involuntary aspects of movement. We measured the peak amplitude of the bass drumhead vibration, synchronization errors as the time elapsed between the metronome onset and the bass drum onset, and amplitude of electromyographic (EMG) recordings centered on metronome beat. Dystonia symptoms primarily manifested in the initial beat, with fewer symptoms on syncopation of the third beat. Analysis revealed decreased bass-drum peak amplitude and earlier synchronization error during the initial beat. EMG measurements of 10 muscles in the affected right lower limb showed significant changes in the Biceps Femoris (BF), Tibialis Anterior (TA), Extensor Digitorum Longus (EDL), and Extensor Digitorum Brevis (EDB) muscles during symptom onset. We observed (1) earlier overactivation of the TA and EDL muscles during the leg lift-up motion or preparatory phase of pedaling, (2) reduced activation of the EDB muscle, and (3) increased activation of the BF muscle during the final pedaling movement when symptoms occurred. These findings suggest that lower-limb dystonia symptoms are characterized by a reduction in amplitude of the bass drumhead vibration and an increase in synchronization error, potentially due to premature overactivation of the ankle dorsiflexor muscles. [ABSTRACT FROM AUTHOR]

There is limited information available on wolverine (Gulo gulo) population density and trends in the boreal forest of North America. We estimated wolverine density using spatial capture‐recapture methods across 2 boreal forest study areas in Red Lake, Ontario (26,568 km2) and Rainbow Lake, Alberta (19,084 km2), Canada. We also used radio‐telemetry data to estimate annual survival of adult and sub‐adult wolverines and evaluated population trends with a stage‐based matrix model. We used an array of run poles and live traps to detect wolverines. In Red Lake over 3 winter field seasons (2019–2022), we detected 56 individual wolverines (17 females, 32 males, and 7 unknown sex), and in Rainbow Lake over 2 field seasons (2014–2016), we detected 48 individuals (19 females, 18 males, and 11 of unknown sex). Average densities in Red Lake and Rainbow Lake were 3.64 and 6.74 wolverines/1,000 km2, respectively. Adults and sub‐adults occurred at equal abundance. Spring snow cover, roads, and industrial developments were not associated with spatial patterns of wolverine density. Most deaths occurred near roads; wolverines were killed in fur traps set along roads, by wolves using roads to travel, and by vehicles. The largest source of death was from incidental (n = 6 in Red Lake) or licensed fur trapping (n = 8 in Rainbow Lake) and we report 8 injuries from fur trapping sets. Red Lake survival estimates for adults (0.87) and sub‐adults (0.86) contributed to a stable population trend. Rainbow Lake survival estimates for adults (0.66) and sub‐adults (0.50) contributed to a declining population trend based on a relatively low sample of radio‐days. Red Lake and Rainbow Lake combined survival estimates for adults (0.77) and sub‐adults (0.73) also contributed to a declining population trend. Our survival and population modeling suggests that human‐caused mortality is a significant risk to these populations. Our results can be applied to wolverine status assessments and used as benchmarks for future monitoring. Wolverine population stability or growth might be achieved by reducing incidental trapping deaths or injury and hindering human access to wolverine habitats through decommissioning or limiting development of industrial roads or other anthropogenic linear features. [ABSTRACT FROM AUTHOR]

In the past, the field of drum source separation faced significant challenges due to limited data availability, hindering the adoption of cutting-edge deep learning methods that have found success in other related audio applications. In this letter, we introduce StemGMD, a large-scale audio dataset of isolated single-instrument drum stems. Each audio clip is synthesized from MIDI recordings of expressive drum performances using ten real-sounding acoustic drum kits. Totaling 1224 h, StemGMD is the largest audio dataset of drums to date and the first to comprise isolated audio clips for every instrument in a canonical nine-piece drum kit. We leverage StemGMD to develop LarsNet, a novel deep drum source separation model. Through a bank of dedicated U-Nets, LarsNet can separate five stems from a stereo drum mixture faster than real-time and is shown to considerably outperform state-of-the-art nonnegative spectro-temporal factorization methods. • The present work is the first to leverage deep learning for drum source separation. • We introduce the largest dataset of isolated drum stems to date (1224 hours). • We introduce the first real-time deep drum source separation model. • We introduce musically-motivated data augmentation methods tailored to drums. • Our model is shown to substantially outperform state-of-the-art methods based on NMF and NMFD. [ABSTRACT FROM AUTHOR]

Precision agriculture has long struggled with the surveillance and control of pests. Traditional methods for estimating pest density and distribution through manual reconnaissance are often time-consuming and labor-intensive. To address these challenges, this study proposes a novel farmland detection system utilizing UAVs, yellow sticky traps, and deep learning techniques. The system includes a UAV based on UWB communication and positioning technology to collect picture information of sticky traps arranged in farmland. Moreover, a faster and more accurate Qpest-RCNN model is used to count the number of insects in the collected sticky traps. The bivariate kernel density estimation establishes the pest density distribution map. Regarding the dynamic monitoring of pest density in agricultural fields, it primarily involves four components: reaching the designated area, flight learning, image acquisition, and visual counting of insects and calculation of insect density. Experimental results demonstrate that UAVs require less time to adjust flight posture during image acquisition after undergoing flight learning, resulting in more concise flight trajectories. The Qpest-RCNN model introduces a variety of mechanisms based on the characteristics of the collected sticky trap data set to improve the faster-R-CNN model. We used two data sets separately to train the model, which were collected by sticky traps placed in greenhouses and open-air experimental fields. The data set from the greenhouse is an open-source dataset provided by M. Deserno et. al, map, precision, and recall of model are 0.923, 0.989, and 0.919, respectively. When the data set collected in the experimental farmland is used to train the model, map, precision, and recall of model are 0.781, 0.851, and 0.789, respectively. In the meantime, we explored the effects of species interference on visual insect statistics and the optimization effect of species hypothesis on statistics in two environments. At the same time, the inference speed of the improved model is about a quarter faster than the FPS of the original Faster-RCNN during inference. Through Qpest-RCNN, the number of insects captured on sticky traps can be counted quickly and accurately and the bivariate kernel density estimation is used to draw the pest density distribution map to observe the pest distribution of the whole farmland visually. This pest-density farmland detection system is valuable for agriculture by helping farmers control pests, reduce crop damage, and increase yield and quality. [ABSTRACT FROM AUTHOR]

A column‐weight k$k$ LDPC code with the parity‐check matrix H$H$ is called decomposable if there exists a permutation π$\pi$ on the rows of H$H$, such that π(H)${\pi }(H)$ can be decomposed into k$k$ column‐weight one matrix. In this paper, some variations of edge coloring of graphs are used to construct some column‐weight three decomposable LDPC codes with girths at least six and eight. Applying the presented method on several known classes of bipartite graphs, some classes of column‐weight three decomposable LDPC codes are derived having flexibility in length and rate. Interestingly, the constructed parity‐check matrices based on the proper edge coloring of graphs can be considered as the base matrix of some high rate column‐weight three quasi‐cyclic (QC) LDPC codes with maximum‐achievable girth 20. The paper also leads to a simple characterization of elementary trapping sets of the decomposable codes based on the chromatic index of the corresponding normal graphs. This characterization corresponds to a simple search algorithm finds all possible existing elementary trapping sets in a girth‐6 or girth‐8 column‐weight 3 LDPC code which are layered super set of a short cycle in the Tanner graph of the code. Simulation results indicate that the QC‐LDPC codes with large girths lifted from the constructed base matrices have good performances over AWGN channel. [ABSTRACT FROM AUTHOR]

Copyright of ISTEM is the property of ISTEM and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• Silverfish are more abundant on lower floors. • Overall insect catch is proportional to the number of traps set. • Catch may be a function of the room perimeter. • Infestations change catch rate, maximum catch on traps and proportion of active traps. Insects can damage museum collections. Heritage organisations are increasingly alert to such risk, so have moved towards integrated pest management which sees monitoring as important to conservation strategies. Museum insects are usually monitored using sticky traps, although the records these provide are not always easy to interpret or analyse, so scoring methods, pest occurrence indices and zone systems have been used to use the observations to manage pests. A six-year trapping programme at almost 700 sites (i.e. traps) across six floors of a large museum in Austria provided a total catch of ∼30 000 arthropods. Catch rate (catch per trap) was higher on lower floors although there was a substantial year-to-year variation. In addition to blunder traps, a proportion using pheromones as an attractant were effective at catching T. bisselliella. The pheromone is not attractive to silverfish (Zygentoma) yet the shy insects appear to take cover in the pheromone traps. In contrast Attagenus spp. were caught at equal rates on both pheromone and blunder traps. The study examined what factors influence the catch of insects in traps. The overall catch in a room is proportional to the number of traps set out. Catch increases with the size of the room, but this may arise because the number of traps is also related to room size. More specifically catch seems proportional to square root of room area, suggesting it relates to its perimeter. Infestations are revealed by high catch rate, maximum catches on a set of traps and the proportion of traps that are active in catching insects. The study aims to assess which parameters that might assist in identifying infested locations in museums. [ABSTRACT FROM AUTHOR]

The Indian Pangolin Manis crassicaudata and the Indian Crested Porcupine Hystrix indica are subject to extensive poaching in Purulia District (West Bengal, India), diminishing their populations, and making the study difficult. Applying methodologies that include local sightings, field observations, camera trapping, and quadrate analysis, these species were observed to co-occur in rocky cavities in Ajodhya hills at several locations. Evidence for this included fresh pangolin tail drag marks, claw prints, footprints, scales, porcupine quills, teeth marks, and faecal matter in the same locations within the study area. Quadrate analysis showed that the trees housing the target prey species of the Indian Pangolin as well as the trees bearing fruits favoured by the Indian Crested Porcupine, occurred at maximum frequency within the Quadrate area. We hypothesise that pangolins and porcupines co-occupy rocky cavities for protection from poachers, who can easily break into more typical burrows and set traps in front of them. This may be an example of adaption to poaching, which demonstrates the necessity of conservation measures to alleviate severe anthropogenic pressure. [ABSTRACT FROM AUTHOR]

Copyright of Therya is the property of Asociacion Mexicana de Mastozoologia, A. C. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The powder spreading process is usually performed at preheating temperature in powder-bed-based additive manufacturing (AM). Thus, the powder flowability characterisation at preheating temperature is important for powder spreading processes. However, devices for traditional powder flowability characterising methods are mainly designed for specific conditions at room temperature and cannot consider the effect of temperature on powder flowability. In this work, an experimental platform with a heated rotating drum was set up and a high-speed camera was used to record powder avalanche processes in a heated rotating drum for the powder flowability characterisation at preheating temperature. Nylon and stainless steel powder flowability at different temperatures was assessed by the statistical analysis of avalanche angle, avalanche time, arithmetic mean deviation and surface linearity of powder surface profile. Four parameters provide a good characterisation of powder flowability. The results can provide guidance for the powder flowability characterisation method at preheating temperature in AM. [ABSTRACT FROM AUTHOR]

In the Internet of Things, sensor nodes collect environmental information and utilize lossy compression for saving storage space. To achieve this objective, high-efficiency compression of the continuous source should be studied. Different from existing schemes, lossy source coding is implemented based on the duality principle in this work. Referring to the duality principle between the lossy source coding and the channel decoding, the belief propagation (BP) algorithm is introduced to realize lossy compression based on a Gaussian source. In the BP algorithm, the log-likelihood ratios (LLRs) are iterated, and their iteration paths follow the connecting relation between the check nodes and the variable nodes in the protograph low-density parity-check (P-LDPC) code. During LLR iterations, the trapping set is the main factor that influences compression performance. We propose the optimized BP algorithms to weaken the impact of trapping sets. The simulation results indicate that the optimized BP algorithms obtain better distortion–rate performance. [ABSTRACT FROM AUTHOR]

Geo-localization has been widely applied as an important technique to get the longitude and latitude for unmanned aerial vehicle (UAV) navigation in outdoor flight. Due to the possible interference and blocking of GPS signals, the method based on image retrieval, which is less likely to be interfered with, has received extensive attention in recent years. The geo-localization of UAVs and satellites can be achieved by querying pre-obtained satellite images with GPS-tagged and drone images from different perspectives. In this paper, an image transformation technique is used to extract cross-view geo-localization information from UAVs and satellites. A single-stage training method in UAV and satellite geo-localization is first proposed, which simultaneously realizes cross-view feature extraction and image retrieval, and achieves higher accuracy than existing multi-stage training techniques. A novel piecewise soft-margin triplet loss function is designed to avoid model parameters being trapped in suboptimal sets caused by the lack of constraint on positive and negative samples. The results illustrate that the proposed loss function enhances image retrieval accuracy and realizes a better convergence. Moreover, a data augmentation method for satellite images is proposed to overcome the disproportionate numbers of image samples. On the benchmark University-1652, the proposed method achieves the state-of-the-art result with a 6.67% improvement in recall rate (R@1) and 6.13% in average precision (AP). All codes will be publicized to promote reproducibility. [ABSTRACT FROM AUTHOR]

Copyright of Biotechnologie, Agronomie, Societe et Environnement is the property of Les Presses Agronomiques de Gembloux and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Birefringent microspheres, trapped in vacuum and set into rotation by circularly polarised light, demonstrate remarkably stable translational motion. This is in marked contrast to isotropic particles in similar conditions. Here we demonstrate that this stability is obtained because the fast rotation of these birefringent spheres reduces the effect of azimuthal spin forces created by the inhomogeneous optical spin of circularly polarised light. At reduced pressures, the unique profile of these rotationally averaged, effective azimuthal forces results in the formation of nano-scale limit cycles. We demonstrate feedback cooling of these non-equilibrium oscillators, resulting in effective temperatures on the order of a milliKelvin. The principles we elaborate here can inform the design of high-stability rotors carrying enhanced centripetal loads or result in more efficient cooling schemes for autonomous limit cycle oscillations. Ultimately, this latter development could provide experimental access to non-equilibrium quantum effects within the mesoscopic regime. By studying levitated optomechanics with birefringent vaterite microspheres in the focus of a circularly polarised light beam, the authors explain the unexpected stability of the trap against azimuthal forces and demonstrate feedback cooling of the residual particle revolutions (limit cycles) in the 2D plane. These findings are a first step towards designing high-stability rotors carrying greater centripetal loads and cooling to the quantum level. [ABSTRACT FROM AUTHOR]

Feral cats (Felis catus) are a significant predator of native birds in Australia, and a recognised predator for the endangered night parrot (Pezoporus occidentalis). We examined camera trapping data from 2014 to 2020 collected at the Pullen Pullen (night parrot) reserve in south-western Queensland to investigate the spatial and temporal patterns of feral cat activity. These data were collected from two discrete periods, with slightly different foci, and we undertook careful data exploration and refinement to identify a consistent data set. We modelled the relationship between the camera detections and a range of environmental, spatial, and temporal parameters, using logistic regression and two selection criteria (Akaike's and Bayesian). The final parsimonious model identified that feral cat detection probability decreased with increasing ruggedness and increased as distance to creek lines decreased. Feral cat detection probability also declined over time from camera deployment. In each model the variance component estimates suggested that some influences on cat detection probability remain unexplained. Regardless, our results provide further data on feral cat activity, and therefore information to focus and improve the management of this threat to the night parrot and other significant species on this conservation reserve. Feral cats are a potential threat to the endangered night parrot. We examined camera trapping data from 2014 to 2020 collected at the night parrot reserve in south-western Queensland to investigate the spatial and temporal patterns of feral cat activity. The final parsimonious model identified that feral cat detection decreased with increasing ruggedness and increased with distance to creek lines. Feral cat detection probability also declined over time from camera deployment. These data will help focus management of feral cats on this important conservation reserve. [ABSTRACT FROM AUTHOR]

It is well known that some harmful objects in the Tanner graph of low-density parity-check (LDPC) codes have a negative impact on their error correction performance under iterative message-passing decoding. Depending on the channel and the decoding algorithm, these harmful objects are different in nature and can be stopping sets, trapping sets, absorbing sets, or pseudocodewords. Differently from LDPC block codes, the design of spatially coupled LDPC codes must take into account the semi-infinite nature of the code, while still reducing the number of harmful objects as much as possible. We propose a general procedure, based on edge spreading, enabling the design of good quasi-cyclic spatially coupled LDPC (QC-SC-LDPC) codes. These codes are derived from quasi-cyclic LDPC (QC-LDPC) block codes and contain a considerably reduced number of harmful objects with respect to the original QC-LDPC block codes. We use an efficient way of enumerating harmful objects in QC-SC-LDPCCs to obtain a fast algorithm that spans the search space of potential candidates to select those minimizing the multiplicity of the target harmful objects. We validate the effectiveness of our method via numerical simulations, showing that the newly designed codes achieve better error rate performance than codes presented in previous literature. [ABSTRACT FROM AUTHOR]

Traditional small mammal survey methods (e.g., Sherman traps) are beneficial in certain conditions but tend to require substantial effort and funds and can introduce various biases. The recently described adapted-Hunt drift fence technique (AHDriFT) camera trap system (i.e., camera traps combined with drift fences) can survey small terrestrial vertebrates and does not require much time in the field. Our objective was to compare the efficiency and effectiveness of AHDriFT systems and traditional Sherman traps for surveying small mammal communities. We conducted surveys with both methods in four sites of varying habitat types at the Eagle Marsh Nature Preserve (Fort Wayne, Indiana) from February to July in 2020 and May to August in 2021. We conducted 640 trap nights (one trap set on one calendar night) of Sherman trap surveys and 551 trap nights of AHDriFT system surveys. We captured 192 small mammals of three species with Sherman traps and obtained 532 images of unique small mammal individuals of seven species with AHDriFT systems. Our AHDriFT systems resulted in two times greater species richness (Z = −6.21, P < 0.01), 16 times greater species evenness (Z = −4.83, P < 0.01), and 23 times greater Shannon's diversity values (Z = −4.87, P < 0.01) than Sherman traps. The AHDriFT systems also documented the presence of four species that the Sherman traps did not (northern short-tailed shrew Blarina brevicauda, common shrew Sorex cinereus, long-tailed weasel Neogale frenata, eastern chipmunk Tamias striatus). Overall, AHDriFT system surveys provided 1.5–5 times more observations per dollar spent and required 90% less time in the field than Sherman trap surveys. These results suggest that AHDriFT systems may be a more efficient and effective method of surveying small mammal communities. [ABSTRACT FROM AUTHOR]

We investigate a quasi-2D suspension of Brownian particles in an optical speckle field produced by holographic manipulation of a laser wavefront. This system was developed to study, in a systematic and controllable way, a distinctive instance of diffusion, called Fickian yet Non Gaussian diffusion (FnGD), observed, during the last decade, for colloidal particles in a variety of complex and biological fluids. Our setup generates an optical speckle field that behaves like a disordered set of optical traps. First, we describe the experimental setup and the dynamics of the particles, focusing on mean square displacements, displacement distributions and kurtosis. Then, we present Brownian Dynamics simulations of point-like particles in a complex energy landscape, mimicking that generated by the optical speckle field. We show that our simulations can capture the salient features of the experimental results, including the emergence of FnGD, also covering times longer than the ones so far achieved in experiments. Some deviations are observed at long time only, with the Gaussian restoring being slower in simulations than in experiments. Overall, the introduced numerical model might be exploited to guide the design of upcoming experiments targeted, for example, to fully monitor the recovery of Gaussianity. [ABSTRACT FROM AUTHOR]