Search

Purpose: Dizziness and imbalance are common symptoms during the acute phase of traumatic brain injury (TBI). However, there is evidence to suggest that these symptoms persist into the chronic phase of injury. Few prospective studies have examined the frequency and type of dizziness and imbalance in adults with chronic moderate--severe TBI. The aim of this preliminary analysis was to investigate the prevalence of these symptoms in adults with chronic moderate--severe TBI. Method: Twenty-four adults with chronic moderate--severe TBI and a group of 19 age-, sex-, and education-matched noninjured comparison participants were recruited. Self-reported dizziness and imbalance were measured using a modified version of a standard case history form. Significant associations between group (TBI group or noninjured comparison [NC] participants) and self-reports of dizziness, imbalance, and related symptoms (endorsed "yes" or "no") were explored. Results: The TBI group most reported lightheadedness (75%), vertigo (38%), and imbalance and/or falling (46%). The most common related symptom reported by the TBI group was headache (63%) and nausea (46%). Significant associations revealed that the TBI group responded "yes" in higher percentages than the NC group across all categories (dizziness, imbalance, and related symptoms). There were no statistically significant relationships among dizziness, imbalance, or headache symptoms within the TBI group. Conclusions: These preliminary findings suggest that dizziness and imbalance are prevalent in adults with chronic moderate--severe TBI. Persistent vertiginous symptoms may point to an underlying vestibular impairment. However, further research is needed to characterize vestibular function in chronic moderate--severe TBI. [ABSTRACT FROM AUTHOR]

The contractile vacuole complex (CVC) is a dynamic and morphologically complex membrane organelle, comprising a large vesicle (bladder) linked with a tubular reticulum (spongiome). CVCs provide key osmoregulatory roles across diverse eukaryotic lineages, but probing the mechanisms underlying their structure and function is hampered by the limited tools available for in vivo analysis. In the experimentally tractable ciliate Tetrahymena thermophila, we describe four proteins that, as endogenously tagged constructs, localize specifically to distinct CVC zones. The DOPEY homolog Dop1p and the CORVET subunit Vps8Dp localize both to the bladder and spongiome but with different local distributions that are sensitive to osmotic perturbation, whereas the lipid scramblase Scr7p colocalizes with Vps8Dp. The H+-ATPase subunit Vma4 is spongiome specific. The live imaging permitted by these probes revealed dynamics at multiple scales including rapid exchange of CVC-localized and soluble protein pools versus lateral diffusion in the spongiome, spongiome extension and branching, and CVC formation during mitosis. Although the association with DOP1 and VPS8D implicate the CVC in endosomal trafficking, both the bladder and spongiome might be isolated from bulk endocytic input. [ABSTRACT FROM AUTHOR]

Dasyhelea bifida Zilahi-Sebess is fully redescribed, photographed and drawn from adults collected in Mexico City by Alfonso Dampf in 1944. This species is compared with the American congeners D. crassiseta Borkent and Forster, D. furva Remm and D. pollex Borkent and Forster. This is a new record of this species from Mexico. [ABSTRACT FROM AUTHOR]

In this study, we propose a model-based tool for the detection of obstructive apnea episodes by using ECG features from a single lead channel. Several sequences of recurrent apnea were provoked in separate 15-min periods in anesthetized rats during an experimental model of obstructive sleep apnea (OSA). Morphology-based ECG markers and the beat-to-beat interval ( R R ) were assessed in each sequence. These markers were used to train dynamic Bayesian networks (DBN) with different orders and feature combinations to find a good tradeoff between network complexity and apnea-detection performance. By using a filtering approach, the resulting DBNs were used to infer the apnea probability signal for subsequent episodes in the same rat. These signals were then processed using by 15-s epochs to determine whether epochs were classified as apneic or nonapneic. Our results showed that fifth-order models provided suitable RMSE values, since higher order models become significantly more complex and present worse generalization. A global threshold of 0.2 gave the best overall performance for all combinations tested, with A c c = 81.3%, S e = 69.8% and S p = 81.5%, using only two parameters including the RR and D s (R-wave downslope) markers. We concluded that multivariate models using DBNs represent a powerful tool for detecting obstructive apnea episodes in short segments, which may also serve to estimate the number of total events in a given time period. [ABSTRACT FROM AUTHOR]

Iris-fixated intraocular lens (IOL) is considered a safe and effective option for the correction of aphakia in patients with insufficient capsular support. This systematic review aims to summarize the existing evidence about the Artisan/Verisyse IOLs and to assess the influence of the IOL position on the postoperative outcomes. Three different databases were used for this systematic review and metaanalysis (PubMED, Scopus, and Embase). We searched for case series or clinical trials comparing the prepupillary versus retropupillary Artisan/Verisyse implantation. The statistical analysis was performed with the programming language R (version 3.6.1 2019-07-05). The number of articles included in the meta-analysis was six, with 506 eyes included in total. We found no significant differences in postoperative corrected distance visual acuity (CDVA) (0.309 [0.089–0.528] vs. 0.32 [0.2–0.44]), spherical equivalent (SE) (0.0153 D [−0.362 to 0.393] vs. −0.329 D [−0.62 to − 0.038]), and central corneal cell density (CECD) (1669.85 cells [1605.949–2150.937] vs. 1635.99 cells [1413.64–1858.363]) between the prepupillary and the retropupillary implantation, respectively. There were no significant differences in the rates of cystoid macular edema (CME; 7.70% vs. 9.8%), pupil deformation (4.5% vs. 5.4% retropupillary), or IOL luxation (2.3% and 2.2%). We found little influence of the IOL position in the postoperative analyzed outcomes. Thus, the implant position should be based on the surgeon's technical experience. Double-blind randomized prospective studies would improve the available evidence on the best implant position for the Artisan/Verisyse IOL. [ABSTRACT FROM AUTHOR]

Retracted papers often circulate widely on social media, digital news, and other websites before their official retraction. The spread of potentially inaccurate or misleading results from retracted papers can harm the scientific community and the public. Here, we quantify the amount and type of attention 3,851 retracted papers received over time in different online platforms. Comparingwith a set of nonretracted control papers fromthe same journals with similar publication year, number of coauthors, and author impact, we show that retracted papers receive more attention after publication not only on social media but also, on heavily curated platforms, such as news outlets and knowledge repositories, amplifying the negative impact on the public. At the same time, we find that posts on Twitter tend to express more criticism about retracted than about control papers, suggesting that criticism-expressing tweets could contain factual information about problematic papers. Most importantly, around the time they are retracted, papers generate discussions that are primarily about the retraction incident rather than about research findings, showing that by this point, papers have exhausted attention to their results and highlighting the limited effect of retractions. Our findings reveal the extent to which retracted papers are discussed on different online platforms and identify at scale audience criticism toward them. In this context, we show that retraction is not an effective tool to reduce online attention to problematic papers. [ABSTRACT FROM AUTHOR]

The deployment of aerial base stations (ABSs) mounted onboard unmanned aerial vehicles is emerging as a promising technology to provide connectivity in areas where terrestrial infrastructure is insufficient or absent. This may occur, for example, in remote areas, large events, emergency situations, or areas affected by natural disasters such as wildfires or tsunamis. To successfully materialize this goal, it is required that ABSs are placed at locations in 3D space that ensure a high quality of service to the ground terminals. This article provides a tutorial introduction to this ABS placement problem where the fundamental challenges and trade-offs are first investigated by means of a toy application example. Next, the different approaches in the literature to address the aforementioned challenges in both 2D or 3D space are introduced, and a discussion on adaptive placement is provided. The article is concluded by discussing future research directions. [ABSTRACT FROM AUTHOR]

Identification of asymptomatic patients at higher risk for suffering cardiac events remains controversial and challenging in Brugada syndrome (BS). In this work, we proposed an ECG-based classifier to predict BS-related symptoms, by merging the most predictive electrophysiological features derived from the ventricular depolarization and repolarization periods, along with autonomic-related markers. The initial feature space included local and dynamic ECG markers, assessed during a physical exercise test performed in 110 BS patients (25 symptomatic). Morphological, temporal and spatial properties quantifying the ECG dynamic response to exercise and recovery were considered. Our model was obtained by proposing a two-stage feature selection process that combined a resampled-based regularization approach with a wrapper model assessment for balancing, simplicity and performance. For the classification step, an ensemble was constructed by several logistic regression base classifiers, whose outputs were fused using a performance-based weighted average. The most relevant predictors corresponded to the repolarization interval, followed by two autonomic markers and two other makers of depolarization dynamics. Our classifier allowed for the identification of novel symptom-related markers from autonomic and dynamic ECG responses during exercise testing, suggesting the need for multifactorial risk stratification approaches in order to predict future cardiac events in asymptomatic BS patients. [ABSTRACT FROM AUTHOR]

Social media sites like Twitter (now X) are increasingly used to create health behavior metrics for public health surveillance. Yet little is known about social norms that may bias the content of posts about health behaviors. Social norms for posts about four health behaviors (smoking tobacco, drinking alcohol, physical activity, eating food) on Twitter/X were evaluated. This was a randomized experiment delivered via web-based survey to adult, English-speaking Twitter/X users in three Michigan, USA, counties from 2020 to 2022 (n =559). Each participant viewed 24 posts presenting experimental manipulations regarding four health behaviors and answered questions about each post's social acceptability. Principal component analysis was used to combine survey responses into one perceived social acceptability measure. Linear mixed models with the Benjamini–Hochberg correction were implemented to test seven study hypotheses in 2023. Supporting six hypotheses, posts presenting healthier (CI: 0.028, 0.454), less stigmatized behaviors (CI: 0.552, 0.157) were more socially acceptable than posts regarding unhealthier, stigmatized behaviors. Unhealthy (CI: −0.268, −0.109) and stigmatized behavior (CI: −0.261, −0.103) posts were less acceptable for more educated participants. Posts about collocated activities (CI: 0.410, 0.573) and accompanied by expressions of liking (CI: 0.906, 1.11) were more acceptable than activities undertaken alone or disliked. Contrary to one hypothesis, posts reporting unusual activities were less acceptable than usual ones (CI: −0.472, 0.312). Perceived social acceptability may be associated with the frequency and content of health behavior posts. Users of Twitter/X and other social media platform posts to estimate health behavior prevalence should account for potential estimation biases from perceived social acceptability of posts. [ABSTRACT FROM AUTHOR]

A number of inference problems with sensor networks involve projecting a measured signal onto a given subspace. In existing decentralized approaches, sensors communicate with their local neighbors to obtain a sequence of iterates that asymptotically converges to the desired projection. In contrast, the present paper develops methods that produce these projections in a finite and approximately minimal number of iterations. Building upon tools from graph signal processing, the problem is cast as the design of a graph filter which, in turn, is reduced to the design of a suitable graph shift operator. Exploiting the eigenstructure of the projection and shift matrices leads to an objective whose minimization yields approximately minimum-order graph filters. To cope with the fact that this problem is not convex, the present work introduces a novel convex relaxation of the number of distinct eigenvalues of a matrix based on the nuclear norm of a Kronecker difference. To tackle the case where there exists no graph filter capable of implementing a certain subspace projection with a given network topology, a second optimization criterion is presented to approximate the desired projection while trading the number of iterations for approximation error. Two algorithms are proposed to optimize the aforementioned criteria based on the alternating-direction method of multipliers. An exhaustive simulation study demonstrates that the obtained filters can effectively obtain subspace projections markedly faster than existing algorithms. [ABSTRACT FROM AUTHOR]

Bees (Apoidea) are the main pollinator group in Mediterranean ecosystems, having a dominant role as connectors of modules (groups of species tightly linked in pollination networks), but little is known about the role of particular species. Here, we analyse data from four Iberian networks, and we pay special attention to the role played by the solitary snail-shell bee Rhodanthidium sticticum (Fabricius, 1787) in shaping network modularity. Our results show that R. sticticum is a pollination generalist that acts as an important connector of modules, strongly influencing the topology of its networks. We also examined 51 networks from all over the world to determine the modular role of other Anthidiini species. Anthidiini were present in 14 of these networks and another Rhodanthidium species, but also two Anthidium species, played a role as connectors in their respective networks. [ABSTRACT FROM AUTHOR]

Species distribution patterns are widely studied through species distribution models (SDMs), focusing mostly on climatic variables. Joint species distribution models (JSDMs) allow inferring if other factors (biotic interactions, shared phylogenetic history or other unmeasured variables) can also have an influence on species distribution. We identified current distributional areas and optimal suitability areas of three species of the solitary snail-shell bee Rhodanthidium (Hymenoptera: Megachilidae), and their host gastropod species in the Iberian Peninsula. We undertook SDMs using Maxent software, based on presence points and climatic variables. We also undertook JSDMs for the bees and the snails to infer if co-occurrence could be a result of biotic interactions. We found that the three bee species: (1) use at least five different species of Mediterranean snails; (2) use empty shells not only for nesting but also for sheltering when there is adverse weather and during the night; (3) have their most suitable areas in the eastern and southern Iberian Peninsula, mostly on limestone areas; and (4) have their optimal range under Mediterranean climatic values for the studied variables. There is positive co-occurrence of Rhodanthidium with the gastropod species, especially with the snail Sphincterochila candidissima. The contribution of the environmental component to the co-occurrence is less than that of the residual component in those cases, suggesting that: (i) the use of biotic resources (between Rhodanthidium and the gastropod species); (ii) shared phylogenetic history (between R. septemdentatum and R. sticticum); or (iii) unmeasured variables are largely responsible for cooccurrence. [ABSTRACT FROM AUTHOR]

Background and Objectives: Military service is a stressful occupation, including increased risk for psychological distress. In order to provide the best care for service members and veterans (SMVs), it is important to understand personality and behavioral patterns associated with negative outcomes. This study examined links between attachment processes, coping styles, problematic alcohol use and psychological distress.Design: Using a cross-sectional, correlational design, a multi-instrument survey was administered to participants either online or in-person.Methods: Veterans and active duty service members (N = 268) completed measures of adult attachment, coping styles, alcohol use, and psychological symptoms.Results: Attachment avoidance was positively associated with avoidant coping, alcohol use, depression, and PTSD symptoms, but negatively related to problem-focused coping. Attachment anxiety was associated with avoidant coping, depression, GAD, and PTSD symptoms. Avoidant coping, but not problem-focused coping, was associated with psychological symptoms, and significant indirect relationships were noted between insecure attachment processes, avoidant coping, and psychological symptoms.Conclusion: Findings highlight personality and behavioral factors that may be important treatment foci when working with SMVs. Future studies should evaluate this model using longitudinal designs. [ABSTRACT FROM AUTHOR]

Brugada syndrome (BS) is a genetic pathological condition associated with a high risk for sudden cardiac death (SCD). Ventricular depolarization disorders have been suggested as a potential electrophysiological mechanism associated with high SCD risk on patients with BS. This paper aims to characterize the dynamic changes of ventricular depolarization observed during physical exercise in symptomatic and asymptomatic BS patients. To this end, cardiac ventricular depolarization features were automatically extracted from 12-lead ECG recordings acquired during standardized exercise stress test in 110 BS patients, of whom 25 were symptomatic. Conventional parameters were evaluated, including QRS duration, R and S wave amplitudes (AR , AS), as well as QRS morphological features, such as up-stroke and down-stroke slopes of the R and S waves (UR , DR and US). The effects of physical exercise and recovery on the dynamics of these markers were assessed in both BS populations. Features showing significantly different dynamics between the studied groups were used alone and in combination with the clinical characteristics of the patients in a logistic regression analysis. Results show larger changes in the second half of the QRS complex through AS and US measured in the right precordial leads for asymptomatic patients, especially during recovery, when the vagal tone is more pronounced. Multivariate analysis involving both types of features resulted in a reduced model of three relevant features (ΔAS in lead V2, Sex and heart rate recovery, HRR), which achieved a suitable discrimination performance between groups; sensitivity = 80% and specificity = 75% (AUC = 83%). However, after controlling the model for possible confounding factors, only one feature (ΔAS) remained meaningful. This adjusted model significantly improved the overall discrimination performance by up to: sensitivity = 84% and specificity = 100% (AUC = 94%). The study highlights the importance of physical exercise test to unmask differentiated behaviors between symptomatic and asymptomatic BS patients through depolarization dynamic analysis. This analysis together with the obtained model may help to identify asymptomatic patients at low or high risk of future cardiac events, but it should be confirmed by further prospective studies. [ABSTRACT FROM AUTHOR]

Background: Personality traits have been associated with a series of dysfunctional behaviors, ranging from violence to drug abuse and other risky behaviors. However, few studies have investigated motorcycle riders' personality traits, and no research using the psychobiological model of personality was found. Thus, we investigated the association between temperament and character traits and the occurrence of Motorcycle Accidents (MAs). Methods: This cross-sectional study was conducted with a randomly selected of 153 Brazilian motorcycle riders (116 male and 37 female) with a mean age of 31.8randomly selected from the driver's license register, between 2015 and 2018. A sociodemographic questionnaire and the Temperament and Character Inventory (TCI) were used. Results: Of the 153 participants, 146 (95.4%) reported having been involved in previous accidents, with the main causes as follows: "other drivers' careless behavior" (34.9%); "personal disrespect of traffic rules" (18.5%) and "personal careless behavior" (20.6%). Motorcyclists exhibited higher scores for the temperament factors of novelty seeking and persistence and lower scores for harm avoidance and reward dependence in comparison to the Brazilian population). Considering the reason for motorcycle use, the group of riders that used their motorcycles for work exhibited more temperament factors associated with risk behaviors than those who did not. It was observed that 68.9% of them had low Harm Avoidance (HA) factor scores, whereas 72.1% had high Novelty Seeking (NS) factor scores. Discussion: The present study highlighted the influences of different personality traits on behaviors, decision-making and risk attitudes that can be potentially harmful to an individual and others. The results provided evidence that a lack of knowledge and experience in riding a motorcycle or any other vehicle, combined with personality traits, contribute to the adoption of risky behaviors that may act as triggers for most causes of Motorcycle Accidents. [ABSTRACT FROM AUTHOR]

Falls are among the most injurious, costly, and feared conditions affecting older adults. Patients with diabetes have a significantly greater risk for falling due to complications affecting the sensory systems required for balance: vision, proprioception, and vestibular. The effects of diabetes mellitus on the vestibular system are perhaps the least understood of these systems. The vestibular system is complex, includes multiple structures, and is difficult and expensive to thoroughly assess. There is pathophysiologic evidence suggesting a direct effect of diabetes mellitus complications on the vestibular system, but there is limited clinical evidence regarding which specific vestibular structures are most adversely affected. Nevertheless, large population-based studies show that patients with diabetes are more likely to have vestibular loss, have a high prevalence of a specific vestibular disorder called benign paroxysmal positional vertigo, and are at a greater risk for falling. Based on the available evidence, a balance screening and an evaluation of benign paroxysmal positional vertigo, a common but easy to treat pathology, in patients with diabetes is recommended as well as counseling on falls risk and home modifications. [ABSTRACT FROM AUTHOR]

Human beings have the habit of labeling everything and everyone. this is something that the recent emergence of social networks has taken to its fullest extent. If the established standards are not fulfilled, it will rain attacks on those who have dared to do or to say something that does not suit them. In this work we approach the queer into the field of contemporary Latin America comics, as a modern reflection of everything that is differentent and, therefore marginal, at a bodily, sexual and gender level. [ABSTRACT FROM AUTHOR]

Spectrum cartography constructs maps of metrics such as channel gain or received signal power across a geographic area of interest using spatially distributed sensor measurements. Applications of these maps include network planning, interference coordination, power control, localization, and cognitive radios to name a few. Since existing spectrum cartography techniques require accurate estimates of the sensor locations, their performance is drastically impaired by multipath affecting the positioning pilot signals. This phenomenon occurs especially in indoor or dense urban scenarios. To overcome such a limitation, this paper introduces a novel paradigm for spectrum cartography, where estimation of spectral maps relies on features of these positioning signals rather than on location estimates. Specific learning algorithms are built on this approach and offer a markedly improved estimation performance than those of the existing approaches relying on localization, as demonstrated by simulation studies in indoor scenarios. [ABSTRACT FROM AUTHOR]

Powder samples (P) of TiO 2 and Pt/TiO 2 were prepared using conventional methods. Then, thin films (TF) incorporating these powders onto SiO 2 films were prepared via dip coating. The powder and thin film samples were characterized by Raman spectroscopy, FESEM, elemental mapping, ICP-OES, HRTEM, UV–vis DRS, and XPS. The samples were then tested in a water-splitting reaction to generate hydrogen, using a water/methanol mixture with a 1:1 volume ratio, and two purple lamps as the radiation sources. The results suggest that incorporating the powder photocatalyst into the thin film resulted in a significant improvement in photocatalytic performance. Furthermore, the thin film samples were more stable during three consecutive runs. [Display omitted] • Thin film photocatalysts were prepared by dip-coating and their performance was compared to the corresponding powder ones. • The incorporation of powder photocatalysts in thin film led to an enhancement of their photocatalytic performance. • Thin film photocatalysts showed higher stability compared to the powder analogs compared to three consecutive runs. • The close interparticle connectivity in the thin film seems to contribute to their superior photocatalytic performance. [ABSTRACT FROM AUTHOR]

Background: One stimulus parameter not well established with respect to the ocular vestibular evoked myogenic potential (oVEMP) is stimulus polarity. Many research studies traditionally record oVEMPs using alternating polarity primarily. Purpose: The purpose of this study was to evaluate the effects of stimulus polarity on the oVEMP response under three different conditions (condensation, rarefaction, and alternating) with updated but established recording procedures-the belly-tendon electrode montage. Research Design: oVEMPs were assessed with changes in stimulus polarity in the seated upright position. Study Sample: Thirty otologically normal participants (60 ears) with no history of hearing or balance disorders and normal middle ear function. Data Collection and Analysis: Five hundred-hertz air-conducted tone bursts at 95-dB nHL were used to evoke the oVEMP response while recordings were made from the contralateral eye to acoustical stimulation using the belly-tendon electrode montage. Measurements were made using three polarities: alternating, condensation, and rarefaction. Natus Bio-logic AEP hardware and software was used for all data collection and analysis. Results: Condensation stimulus phase provided the largest response amplitude compared with alternating and/or rarefaction. Rarefaction provided the earliest latency among stimulus polarities. Conclusions: Condensation is a more effective stimulus polarity regarding response amplitude when recording the oVEMP. This study further supports the use of the belly-tendon electrode montage for recording the oVEMP response. [ABSTRACT FROM AUTHOR]

Abstract Buffelgrass is an African grass commonly established in pastures in arid and semiarid regions as forage for livestock. However, once established in pastures, this grass spreads and invades adjacent habitats. We evaluated buffelgrass cover along invaded roadsides and adjacent lands in the state of Sonora, Mexico to explore how land use affect invasion. Additionally, we evaluated the abundance and influence of buffelgrass in five invaded plant communities. We recorded buffelgrass in 63.6% of the sampled sites along roadsides and in 17.5% of adjacent lands in the state of Sonora. Land use has a significant effect on adjacent roadside buffelgrass cover, probably through propagule pressure. Buffelgrass abundance ranged from 1633 to 10,399 adult plants per hectare and from 0 to 1811 seeds/m2 in invaded plant communities. Our analysis of five invaded sites revealed a significant effect of buffelgrass invasion through a reduction on species diversity. Overall, our data from five sites suggest that buffelgrass invasion in rangelands is having an impact of native plant communities in the state of Sonora. Highlights • In this study we found that buffelgrass has invaded 63% of roadsides and 17.5% of adjacent lands with different land uses in the state of Sonora. • In this region, land use influence buffelgrass cover along roadsides. • Our data suggest that buffelgrass invasion is having an impact of native plant communities in the state of Sonora. [ABSTRACT FROM AUTHOR]

It is crucial for large-scale communication networks such as the internet to be resilient against attacks such as censorship and surveillance, which pose a threat to free expression and free association. Self-organized networks such as the internet’s router network typically have heavy-tailed degree distributions, making them highly vulnerable to targeted attacks against central nodes. While cryptographic solutions exist, they fail to address the underlying topological problem, and remain vulnerable to man-in-the-middle attacks and coercion. Coercion-resistant, topological approaches to attack tolerance are needed to address the current vulnerability of communications infrastructure to censorship and surveillance. We present a novel concurrent multipath routing (CMR) algorithm for the wraparound butterfly network topology, as well as a highly attack-tolerant Structured Multipath Fault Tolerance (SMFT) architecture which incorporates the butterfly CMR algorithm. We also identify a previously unexplored relationship between network topology, trust transitivity, and attack-tolerance, and provide a framework for further exploration of this relationship. Our work is the first theoretical demonstration of a point-to-point communication network architecture that can resist coercion and other non-technical attacks, without requiring infinitely transitive trust. To address cases where the network structure cannot be fully controlled, we demonstrate how a snapshot of the internet’s router network can be partially rewired for greater attack-tolerance. More broadly, we hope that this work will serve as a starting point for the evelopment of additional topology-based attack-tolerant communication architectures to guard against the dangers of censorship and surveillance. [ABSTRACT FROM AUTHOR]

This paper studies the existence of optimal invariant detectors for determining whether $P$ multivariate processes have the same power spectral density. This problem finds application in multiple fields, including physical layer security and cognitive radio. For Gaussian observations, we prove that the optimal invariant detector, i.e., the uniformly most powerful invariant test, does not exist. Additionally, we consider the challenging case of close hypotheses, where we study the existence of the locally most powerful invariant test (LMPIT). The LMPIT is obtained in the closed form only for univariate signals. In the multivariate case, it is shown that the LMPIT does not exist. However, the corresponding proof naturally suggests an LMPIT-inspired detector that outperforms previously proposed detectors. [ABSTRACT FROM AUTHOR]

Identifying rainfall regions associated with specific modes of variability is of practical interest for water resources management, seasonal forecasting, and mitigation of weather‐related risks. This study aims to identify homogeneous rainfall regions within the ~1 million km2 Upper Madeira River basin—southwestern Amazon—by their interannual and decadal variability and relates this variability to ocean indices. An observed dataset of 146 ground‐based rainfall stations, distributed throughout the Andes and the Amazon, and homogenized at the monthly time‐step for the period 1980–2016, was used for the analysis. With no spatial constraints, hierarchical cluster analysis and principal component analysis (PCA) optimally grouped stations into 10 rainfall homogenous regions. The value of the regionalization for interpreting the rainfall variability was evaluated by relating the seasonal rainfall time series of the regions with ocean indices. Then, by applying PCA to seasonal rainfall series and linking the principal components to sea surface temperature and ocean indices, an insight into the main large‐scale drivers of the rainfall spatio‐temporal variability in this basin at interannual and decadal scales is provided. This analysis identified differences in the year‐round influences of the tropical Pacific and/or Atlantic oceans on the 10 homogenous regions. [ABSTRACT FROM AUTHOR]

Inference of space-time varying signals on graphs emerges naturally in a plethora of network science related applications. A frequently encountered challenge pertains to reconstructing such dynamic processes, given their values over a subset of vertices and time instants. The present paper develops a graph-aware kernel-based kriged Kalman filter that accounts for the spatio-temporal variations, and offers efficient online reconstruction, even for dynamically evolving network topologies. The kernel-based learning framework bypasses the need for statistical information by capitalizing on the smoothness that graph signals exhibit with respect to the underlying graph. To address the challenge of selecting the appropriate kernel, the proposed filter is combined with a multikernel selection module. Such a data-driven method selects a kernel attuned to the signal dynamics on-the-fly within the linear span of a preselected dictionary. The novel multikernel learning algorithm exploits the eigenstructure of Laplacian kernel matrices to reduce computational complexity. Numerical tests with synthetic and real data demonstrate the superior reconstruction performance of the novel approach relative to state-of-the-art alternatives. [ABSTRACT FROM AUTHOR]

Ventricular arrhythmias in Brugada syndrome (BS) typically occur at rest and especially during sleep, suggesting that changes in the autonomic modulation may play an important role in arrhythmogenesis. The autonomic response to exercise and subsequent recovery was evaluated on 105 patients diagnosed with BS (twenty-four were symptomatic), by means of a time-frequency heart rate variability (HRV) analysis, so as to propose a novel predictive model capable of distinguishing symptomatic and asymptomatic BS populations. During incremental exercise, symptomatic patients showed higher HFnu values, probably related to an increased parasympathetic modulation, with respect to asymptomatic subjects. In addition, those extracted HRV features best distinguishing between populations were selected using a two-step feature selection approach, so as to build a linear discriminant analysis (LDA) classifier. The final features subset included one third of the total amount of extracted autonomic markers, mostly acquired during incremental exercise and active recovery, thus evidencing the relevance of these test segments in BS patients classification. The derived predictive model showed an improved performance with respect to previous works in the field (AUC = 0.92 ± 0.01; Se = 0.91 ± 0.06; Sp = 0.90 ± 0.05). Therefore, based on these findings, some of the analyzed HRV markers and the proposed model could be useful for risk stratification in Brugada syndrome. [ABSTRACT FROM AUTHOR]

From the attenuation measurements collected by a network of spatially distributed sensors, radio tomography constructs spatial loss fields (SLFs) that quantify absorption of radiofrequency waves at each location. These SLFs can be used for interference prediction in (possibly cognitive) wireless communication networks, for environmental monitoring or intrusion detection in surveillance applications, for through-the-wall imaging, for survivor localization after earthquakes or fires, etc. The cornerstone of radio tomography is to model attenuation as the bidimensional integral of the SLF of interest scaled by a weight function. Unfortunately, existing approaches (i) rely on heuristic assumptions to select the weight function and (ii) are limited to imaging changes in the propagation medium or they require a separate calibration step with measurements in free space. The first major contribution in this paper addresses (i) by means of a blind radio tomographic approach that learns the SLF together with the aforementioned weight function from the attenuation measurements. This challenging problem is tackled by capitalizing on contemporary kernel-based learning tools together with various forms of regularization that leverage prior knowledge. The second contribution addresses (ii) by means of a novel calibration technique capable of imaging static structures without separate calibration steps. Numerical tests with real and synthetic measurements validate the efficacy of the proposed algorithms. [ABSTRACT FROM AUTHOR]

Power spectral density (PSD) maps providing the distribution of RF power across space and frequency are constructed using power measurements collected by a network of low-cost sensors. By introducing linear compression and quantization to a small number of bits, sensor measurements can be communicated to the fusion center with minimal bandwidth requirements. Strengths of data- and model-driven approaches are combined to develop estimators capable of incorporating multiple forms of spectral and propagation prior information while fitting the rapid variations of shadow fading across space. To this end, novel nonparametric and semiparametric formulations are investigated. It is shown that PSD maps can be obtained using support vector machine-type solvers. In addition to batch approaches, an online algorithm attuned to real-time operation is developed. Numerical tests assess the performance of the novel algorithms. [ABSTRACT FROM PUBLISHER]

One advantage of crowds over traditional teams is that crowds enable the assembling of a large number of individuals to address problems. The literature is unclear, however, about when crowd size leads to better outcomes. To better understand the effects of crowd size we conducted a study on the retention and performance of 4,317 articles in the WikiProject Film community. Results indicate that crowd composition, specifically diversity and experience, is vital to understanding when size leads to better retention and performance. Crowd size was positively related to retention and performance when crowds were high in diversity and experience. Retention was important to determining when crowd size led to better performance. Crowd size was positively related to performance when retention was low. Our results suggest that crowds benefit from their size when they are diverse, experienced, and have low retention rates. [ABSTRACT FROM AUTHOR]

The specialised conducting tissues present in the ventricles are responsible for the fast distribution of the electrical impulse from the atrio-ventricular node to regions in the subendocardial myocardium. Characterisation of anatomical features of the specialised conducting tissues in the ventricles is highly challenging, in particular its most distal section, which is connected to the working myocardium via Purkinje-myocardial junctions. The goal of this work is to characterise the architecture of the distal section of the Purkinje network by differentiating Purkinje cells from surrounding tissue, performing a segmentation of Purkinje fibres at cellular scale, and mathematically describing its morphology and interconnections. Purkinje cells from rabbit hearts were visualised by confocal microscopy using wheat germ agglutinin labelling. A total of 16 3D stacks including labeled Purkinje cells were collected, and semi-automatically segmented. State-of-the-art graph metrics were applied to estimate regional and global features of the Purkinje network complexity. Two types of cell types, tubular and star-like, were characterised from 3D segmentations. The analysis of 3D imaging data confirms the previously suggested presence of two types of Purkinje-myocardium connections, a 2D interconnection sheet and a funnel one, in which the narrow side of a Purkinje fibre connect progressively to muscle fibres. The complex network analysis of interconnected Purkinje cells showed no small-world connectivity or assortativity properties. These results might help building more realistic computational PK systems at high resolution levels including different cell configurations and shapes. Better knowledge on the organisation of the network might help in understanding the effects that several treatments such as radio-frequency ablation might have when the PK system is disrupted locally. [ABSTRACT FROM AUTHOR]

• Adding cardiopulmonary markers to physical parameters improve classical 6MWD models in COPD. • No walking exercise is needed to estimate 6MWT outcomes using Bayesian networks. • Disease severity in COPD can be inferred based on actual patient's 6MWT outcomes. • Personalized models of disease progression may help to reduce hospitalization and mortality in COPD. Chronic obstructive pulmonary disease (COPD) requires a multifactorial assessment, evaluating the airflow limitation and symptoms of the patients. The 6-min walk test (6MWT) is commonly used to evaluate the functional exercise capacity in these patients. This study aims to propose a novel predictive model of the major 6MWT outcomes for COPD assessment, without physical performance measurements. Cardiopulmonary and clinical parameters were obtained from fifty COPD patients. These parameters were used as inputs of a Bayesian network (BN), which integrated three multivariate models including the 6-min walking distance (6MWD), the maximum HR (HR max) after the walking, and the HR decay 3 min after (HRR 3). The use of BN allows the assessment of the patients' status by predicting the 6MWT outcomes, but also inferring disease severity parameters based on actual patient's 6MWT outcomes. Firstly, the correlation obtained between the estimated and actual 6MWT measures was strong (R = 0.84, MAPE = 8.10% for HR max) and moderate (R = 0.58, MAPE = 15.43% for 6MWD and R = 0.58, MAPE = 32.49% for HRR 3), improving the classical methods to estimate 6MWD. Secondly, the classification of disease severity showed an accuracy of 78.3% using three severity groups, which increased up to 84.4% for two defined severity groups. We propose a powerful two-way assessment tool for COPD patients, capable of predicting 6MWT outcomes without the need for an actual walking exercise. This model-based tool opens the way to implement a continuous monitoring system for COPD patients at home and to provide more personalized care. [ABSTRACT FROM AUTHOR]

As part of the technology research engaged in the EU Clean Sky 1 project, we present in this paper an electrical structure network (ESN) designed to prevent the impact on an electronic equipment of unwanted voltage drops appearing when nonmetal composite materials are used for grounding. An iterative process has been followed to reach an optimal tradeoff solution meeting all the aircraft requirements: structural, safety, low weight, electrical, etc. Guidelines on the design of a low-impedance metal ESN, to minimize the inductive behavior of the power distribution network, are outlined in this paper. To this end, we employ the UGRFDTD simulation tool, combining finite-difference time domain to analyze the general EM problem, and a multiconductor transmission-line network to handle internal coupling between cables running along coinciding routes. The capability of this tool to create time-domain snapshots of surface currents is shown to provide a useful way to optimize the ESN, thanks to the insight gained on the physics of the problem. [ABSTRACT FROM PUBLISHER]

Buffelgrass ( Pennisetum ciliare ) have been planted in large areas of northwestern Mexico for cattle grazing. Previous studies have documented how buffelgrass conversion affects several ecological processes; however, very few studies have documented how conversion affects local microclimate. We used data on soil temperature and moisture to document seasonal changes in microclimate as a consequence of land conversion. We describe soil and air temperature and soil moisture content in a thornscrub and an adjacent buffelgrass pasture, in open spaces and under trees, during one year. Air temperature in the pasture exceeded ∼1 °C the value in the thornscrub during the colder months. Mean soil temperatures were slightly greater in the thornscrub during the dry season but during the wet season, mean temperatures were greater in the pasture reaching differences of ∼2 °C. Maximum monthly soil temperatures were greater in the pasture after the wet season with values that reached 6 °C above the thornscrub. Soil moisture showed significant greater values in the thornscrub than in the pasture. Our data suggest that conversion of thornscrub to buffelgrass pasture modify the local microclimate, which in turn could influence the process of regeneration of native species persisting in pastures. [ABSTRACT FROM AUTHOR]

The measurement invariance of the Modern Homonegativity Scale (MHS) was examined among heterosexual female (n = 449) and male (n = 329) university students who were predominantly Mexican American. The MHS demonstrated full invariance of factor loadings and partial invariance of latent intercepts. At the latent mean level, heterosexual men compared to heterosexual women held more negative attitudes toward both gay men and lesbian women. There were no latent mean differences in attitudes toward gay men and lesbian women when rated by either heterosexual men or heterosexual women. The MHS can be used by heterosexual men and heterosexual women to assess their homonegativity. [ABSTRACT FROM PUBLISHER]

In this paper, two problems that show great similarities are examined. The first problem is the reconstruction of the angular-domain periodogram from spatial-domain signals received at different time indices. The second one is the reconstruction of the frequency-domain periodogram from time-domain signals received at different wireless sensors. We split the entire angular or frequency band into uniform bins. The bin size is set such that the received spectra at two frequencies or angles, whose distance is equal to or larger than the size of a bin, are uncorrelated. These problems in the two different domains lead to a similar circulant structure in the so-called coset correlation matrix. This circulant structure allows for a strong compression and a simple least-squares reconstruction method. The latter is possible under the full column rank condition of the system matrix, which can be achieved by designing the spatial or temporal sampling patterns based on a circular sparse ruler. We analyze the statistical performance of the compressively reconstructed periodogram, including bias and variance. We further consider the case when the bins are so small that the received spectra at two frequencies or angles, with a spacing between them larger than the size of the bin, can still be correlated. In this case, the resulting coset correlation matrix is generally not circulant and thus a special approach is required. [ABSTRACT FROM PUBLISHER]

An editorial is presented on severe acute respiratory syndrome coronavirus (SARS-CoV-2) declaring a pandemic by the World Health Organization (WHO). Topics include data suggesting the strain leading to a more serious illness than previous mutations; and having fever, chills, cough, shortness of breath, fatigue, muscle or body aches, headache, and loss of taste or smell.

An introduction is presented in which the editor discusses articles in the issue on topics including PostInfection Hearing; COVID-19 infection; and Audiological Tests.

Mexico participates in initiatives and agreements on climate change. Studies have been carried out and legislation produced to address this phenomenon. In the Guadalajara Metropolitan Area (ZMG in Spanish), the second-largest urban area in Mexico, meteorological and geographical vulnerability studies of the territory have been done that offer an overview of the situation, which depends on the physical characteristics of the area at risk, as well as the structural vulnerability of the infrastructure and equipment. As a result of catastrophic events, social and organizational spheres become Involved, public and private connect; and their intersection creates vulnerability interdependence, due to proximity, interactions and Interfaces in the occupation of spaces, land use and activities In the territory. Urban resilience Is understood here as the resistance of a system that absorbs disruptions, and adapts and organizes itself to regain a balance similar to that experienced prior to the extreme event. [ABSTRACT FROM AUTHOR]

With rising numbers of student veterans on today's college campuses, multicultural competence in college counseling centers increasingly includes an understanding of military culture and its relation to the psychological health and functioning of student veterans. Research on interpersonal and intrapersonal factors associated with college student veterans' mental health is scarce. The current study examines the contributions of coping style and family social support on symptoms of anxiety, depression, and posttraumatic stress in a student veteran sample. We also tested the moderating role of family social support in the relationship between coping style and psychological symptoms. Data from 136 student veterans were analyzed by using path analysis. Results revealed that avoidant coping and family social support significantly predicted depressive and anxiety symptoms. Avoidant coping also significantly predicted posttraumatic stress symptoms. In addition, findings indicated that family social support moderated the relationship between problem-focused coping and depression, as well as between avoidant coping and symptoms of anxiety and depression but not posttraumatic stress. Implications of results for college and university counselors are discussed. [ABSTRACT FROM AUTHOR]

The class of complex random vectors whose covariance matrix is linearly parameterized by a basis of Hermitian Toeplitz (HT) matrices is considered, and the maximum compression ratios that preserve all second-order information are derived—the statistics of the uncompressed vector must be recoverable from a set of linearly compressed observations. This kind of vectors arises naturally when sampling wide-sense stationary random processes and features a number of applications in signal and array processing. Explicit guidelines to design optimal and nearly optimal schemes operating both in a periodic and nonperiodic fashion are provided by considering two of the most common linear compression schemes, which we classify as dense or sparse. It is seen that the maximum compression ratios depend on the structure of the HT subspace containing the covariance matrix of the uncompressed observations. Compression patterns attaining these maximum ratios are found for the case without structure as well as for the cases with circulant or banded structure. Universal samplers are also proposed to compress unknown HT subspaces. [ABSTRACT FROM PUBLISHER]

In many regions of the world, land conversion of native plant communities to non-native pastures is usually associated with significant changes in soil nutrient contents. In Mexico, more than one million hectares of drylands have been converted to non-native pastures, with little knowledge on the biogeochemical consequences. We investigated the effects of non-native buffelgrass ( Pennisetum ciliare ) pasture conversion on soil carbon (C), nitrogen (N) and phosphorus (P) dynamics to understand the effects of disturbance on soil nutrient in a region of the state of Sonora. Eleven sites that formed a gradient (1–44 years) of buffelgrass establishment history where buffelgrass establishment has been practiced for at least 50 years, were studied. Soil organic C, total N and P, microbial biomass C, extractable P, and mineral N contents and basal soil respiration, were measured in samples collected during the dry and rainy seasons in buffelgrass pastures and undisturbed thornscrub. Conversion to buffelgrass pastures decreased mineral N content and basal soil respiration. Extractable P decreased in older pastures (>10 years), suggesting a potential P-limitation for the permanence of long-term buffelgrass pastures in Sonora. In contrast, we did not detect a significant reduction of soil organic C, total N and P in older pastures. This study suggests that P limitation may serve as important controls on ecosystem nutrient cycling in natural vegetation and recovery of these thornscrubs after buffelgrass pasture establishment for cattle ranching. [ABSTRACT FROM AUTHOR]

Spectrum sensors for cognitive radio are expected to deploy multiple antennas to overcome the noise uncertainty problem and to minimize the effects of small-scale fading. Despite the requirement that these sensors must detect wireless microphone (WM) signals, several studies have focused either on general-purpose multiantenna detectors or on single-antenna WM detectors. We exploit the spatial structure and particular properties of WM waveforms to derive four multiantenna detectors for WM signals with different performance/complexity tradeoffs. These detectors are based on the generalized likelihood ratio (GLR) test, which is derived under several signal models exploiting either that the bandwidth of a WM signal never exceeds 200 kHz, that these signals have a constant magnitude (CM), or both. The proposed detectors do not require synchronization with the WM signal and are robust to the noise uncertainty problem and to small-scale fading. Using the simulation guidelines from the IEEE 802.22 standard, the novel multiantenna WM detectors are shown to outperform previous schemes, thus demonstrating the advantages of exploiting spatial correlation along with the WM signal structure. [ABSTRACT FROM AUTHOR]

This document shows the details of the implementation of a fuzzy inference system, for the identification of four over-the-counter drugs (Naproxen, Calcium Carbonate, Muvett and Winadol), by using a Raman Spectroscopy, which output is the characterization of the substance. Data obtained from Raman Spectroscopy are modeled with Matlab®- Fuzzy Logic Toolbox. [ABSTRACT FROM AUTHOR]

In this study, several electrocardiogram (ECG)-derived indices corresponding to both ventricular depolarization and repolarization were evaluated during acute myocardial ischemia in an experimental model of myocardial infarction produced by 40 min coronary balloon inflation in 13 pigs. Significant changes were rapidly observed from minute 4 after the start of coronary occlusion, achieving their maximum values between 11 and 22 min for depolarization and between 9 and 12 min for repolarization indices, respectively. Subsequently, these maximum changes started to decrease during the latter part of the occlusion. Depolarization changes associated with the second half of the QRS complex showed a significant but inverse correlation with the myocardium at risk (MaR) estimated by scintigraphic images. The correlation between MaR and changes of the downward slope of the QRS complex, IDS, evaluated at the two more relevant peaks observed during the occlusion, was r = -0.75, p ﹤ 0.01 and r = -0.79, p ﹤ 0.01 for the positive and negative deflections observed in IDS temporal evolution, respectively. Repolarization changes, analyzed by evaluation of ST segment elevation at the main observed positive peak, also showed negative, however non-significant correlation with MaR: r = -0.34, p = 0.28. Our results suggest that changes evaluated in the latter part of the depolarization, such as those described by IDS, which are influenced by R-wave amplitude, QRS width and ST level variations simultaneously, correlate better with the amount of ischemia than other indices evaluated in the earlier part of depolarization or during the ST segment. [ABSTRACT FROM AUTHOR]

In this paper, we present a modeling methodology to couple the cardiac conduction system to cardiac myocytes through a model of Purkinje-ventricular junctions to yield fast and realistic electrical activation of the ventricles. A patient-specific biventricular geometry is obtained from processing computed tomography scan data. A one-manifold implementation of the fast marching method based on Eikonal-type equations is used for modeling heart electrophysiology, which facilitates the multiscale 1-D–3-D coupling at very low computational costs. The method is illustrated in in-silico experiments where we analyze and compare alternative pacing strategies on the same patient-specific anatomy. We also show very good agreement between the results from the proposed approach and more detailed and comprehensive biophysical models for modeling cardiac electrophysiology. The effect of atrioventricular delay on the distribution of activation time in myocardium is studied with two experiments. Given the reasonable computational times and realistic activation sequences provided by our method, it can have an important clinical impact on the selection of optimal implantation sites of pacing leads or placement of ablation catheter’s tip in the context of cardiac rhythm management therapies. [ABSTRACT FROM AUTHOR]

Diagnosis and risk stratification of patients with acute coronary syndromes can be improved by adding information from the depolarization phase (QRS complex) to the conventionally used ST-T segment changes. In this study, ischemia-induced changes in the main three slopes of the QRS complex, upward (\cal I{US}) and downward (\cal I{DS}) slopes of the R wave as well as the upward (\cal I{TS}) slope of the terminal S wave, were evaluated as to represent a robust measure of pathological changes within the depolarization phase. From ECG recordings both in a resting state (control recordings) and during percutaneous coronary intervention (PCI)-induced transmural ischemia, we developed a method for quantification of \cal I{US}, \cal I{DS}, and \cal I{TS} that incorporates dynamic ECG normalization so as to improve the sensitivity in the detection of ischemia-induced changes. The same method was also applied on leads obtained by projection of QRS loops onto their dominant directions. We show that \cal I{US}, \cal I{DS}, and \cal I{TS} present high stability in the resting state, thus providing a stable reference for ischemia characterization. Maximum relative factors of change (\cal R{\cal I}) during PCI were found in leads derived from the QRS loop, reaching 10.5 and 13.7 times their normal variations in the control for \cal I{US} and \cal I{DS}, respectively. For standard leads, the relative factors of change were 6.01 and 9.31. The \cal I{TS} index presented a similar behavior to that of \cal I{DS}. The timing for the occurrence of significant changes in \cal I{US} and \cal I{DS} varied with lead, ranging from 30 s to 2 min after initiation of coronary occlusion. In the present ischemia model, relative \cal I{DS} changes were smaller than ST changes in most leads, however with only modest correlation between the two indices, suggesting they present different information about the ischemic process. We conclude that QRS slopes offer a robust tool for evaluating depolarization changes during myocardial ischemia. [ABSTRACT FROM AUTHOR]

The papers of Leonetti (2001, 2004) and Escandell Vidal and Leonetti (1997) hypothesized that the functional categories (FFCC) proposed in the Minimalist Program of Chomsky (1995, 1998, 1999, 2005) are the procedural categories proposed by Relevance Theory (Sperber and Wilson, [1986] 1995). This is demonstrated convincingly for some of the FFCC, the Determinant and the Complementizer, for example, but there is no mention of the FC light verb (v̲). This paper will attempt to show that v̲ can also be considered a procedural category. [ABSTRACT FROM AUTHOR]

We show through an analysis of a massive data set from YouTube that the productivity exhibited in crowdsourcing exhibits a strong positive dependence on attention, measured by the number of downloads. Conversely, a lack of attention leads to a decrease in the number of videos uploaded and the consequent drop in productivity, which in many cases asymptotes to no uploads whatsoever. Moreover, short-term contributors compare their performance to the average contributor's performance while long-term contributors compare it to their own media. [ABSTRACT FROM AUTHOR]