On predicting sociodemographics from mobility signals

Objective The aim of this study was to conduct a detailed geospatial analysis of mobile phone signal coverage in the northwest macro-region of Paraná State, Brazil, seeking to identify areas where limitations in coverage may be related to lengthy travel times of the helicopter emergency medical service (HEMS) for the assistance of victims of road traffic injuries (RTIs). Methods An observational study was conducted to examine mobile phone signal coverage and HEMS travel times from 2017 to 2021. HEMS travel times were categorized into four groups: T1 (0–15 min), T2 (16–30 min), T3 (31–45 min), and T4 (over 45 min). Empirical Bayesian Kriging was used to map areas with low mobile signal coverage. The Kruskal–Wallis test and Dwass–Steel–Critchlow–Fligner comparative analyses were performed to explore how mobile signal coverage relates to HEMS travel times to RTI locations. Results There were 470 occurrences of RTIs attended by HEMS, of which 108 (23%) resulted in on-site fatalities. Among these deaths, 47 (26.85%) occurred in areas with low mobile phone signal coverage (“shadow areas”). Low mobile phone signal coverage identified at 175 (37.24%) RTIs locations, was unevenly distributed across the macro-region. The lowest medians of mobile signal quality were predominantly found in areas with HEMS travel times exceeding 30 min, corresponding to signal strength values of −98.44 (T3) and −100.75 (T4) dBm. This scenario represents a challenge for effective communication to activate HEMS. In the multiple comparison analysis among travel time groups, significant differences were observed between T1 and T2 (p < 0.001), T1 and T3 (p < 0.001), T1 and T4 (p < 0.001), and T2 and T3 (p < 0.001), indicating a potential association between lower mobile phone signal coverage and longer HEMS travel times. Conclusion It can be concluded that poor mobile phone signals in remote areas can hinder HEMS activation, potentially delaying the start of treatment for RTIs. Identification of the shadow areas can help communication and health managers in designing and implementing the necessary changes to improve mobile phone signal coverage and consequently reduce delays in the initial response to RTIs.

Post-transcriptional gene silencing (PTGS) is a sequence-specific RNA degradation mechanism that is widespread in eukaryotic organisms. It is often associated with methylation of the transcribed region of the silenced gene and with accumulation of small RNAs (21 to 25 nucleotides) homologous to the silenced gene. In plants, PTGS can be triggered locally and then spread throughout the organism via a mobile signal that can cross a graft junction. Previously, we showed that the helper component-proteinase (HC-Pro) of plant potyviruses suppresses PTGS. Here, we report that plants in which PTGS has been suppressed by HC-Pro fail to accumulate the small RNAs associated with silencing. However, the transgene locus of these plants remains methylated. Grafting experiments indicate that HC-Pro prevents the plant from responding to the mobile silencing signal but does not eliminate its ability to produce or send the signal. These results demonstrate that HC-Pro functions downstream of transgene methylation and the mobile signal at a step preceding accumulation of the small RNAs.

An Intact Cuticle in Distal Tissues Is Essential for the Induction of Systemic Acquired Resistance in Plants

This paper addresses the problem of non-ETC (Electronic Toll Collection) vehicles lacking real-time notification channels by proposing a method based on mobile signaling. This approach leverages time and spatial data contained in mobile signals to match vehicle license plates with phone numbers, establishing an effective mechanism to reach non-ETC vehicle users. By integrating license plate recognition systems, mobile phone signaling data, and advanced positioning algorithms, a comprehensive system architecture is designed in this paper. The data processing flow, positioning algorithms, and experimental verification processes are elaborated, demonstrating the feasibility and effectiveness of this technology within closed tunnels. The experimental results demonstrate that the method has high accuracy and stability, providing a solution to the problem of notifying non-ETC vehicle users.

Jasmonic Acid Transport in Wound-Induced Systemic Immunity

Testing the mobile network signal strength is essential for evaluating actual user experience. This procedure is done by measurement campaign, where a person or a group of people walk or drive through the target area holding a measuring equipment. However, this is not suitable to do in hard-to-reach areas. In order to minimize human involvement and to reduce resources, labour, and time consumed, an alternative approach for physical assessment of cellular coverage and quality evaluating is needed. In this work, we used a drone to measure mobile network signal strength to generate a two-dimensional coverage map for difficult-to-reach areas. A machine learning algorithm is used to estimate the signal strength in other locations within the area to generate a dense 2D coverage map. The measurements were done on Sultan Qaboos University Campus, Muscat, Oman. Our finding shows that a drone equipped with a low-cost signal strength measuring device and an artificial neural network (ANN) algorithm are able to generate an accurate dense map of mobile signal strength in a flexible and cost-effective manner. The ANN was capable of predicting the signal strength at the ground from measurement at higher altitudes with an accuracy of 97%.

Jasmonates (JAs)-mediated pathways are central signaling hubs in plant defense responses. However, the identification of mobile and nonmobile signals involved in downstream systemic signaling is still less studied. Here, we investigate the role of the jasmonic acid-isoleucine (JA-Ile) conjugating enzyme, JAR1, in shifting wound-induced local and systemic metabolic profiles using liquid chromatography mass spectrometry (LC-MS/MS) for untargeted metabolomics, and the mobility of JA-Ile in wound-induced local and systemic defense using LC-MS/MS for targeted JAs analysis in Arabidopsis thaliana leaves. The use of jarin-1, a specific inhibitor of JA-Ile biosynthesis, suggested that JA-Ile was synthesized de novo in the particular tissues, rather than being a mobile signal. In addition, inhibition of JAR1 enzyme activity affected an array of downstream metabolic pathways, locally and systemically, such as amino acids and carbohydrate metabolism. This study suggests that the occurrence and spread of local and systemic downstream signals very likely depend on JAR1 activity, and this enzyme exclusively regulates a series of metabolic pathways under both wounding and nonwounding conditions.

Importers Drive Leaf-to-Leaf Jasmonic Acid Transmission in Wound-Induced Systemic Immunity

Florigen, the mobile signal that moves from an induced leaf to the shoot apex and causes flowering, has eluded identification since it was first proposed 70 years ago. Understanding the nature of the mobile flowering signal would provide a key insight into the molecular mechanism of floral induction. Recent studies suggest that the Arabidopsis FLOWERING LOCUS T (FT) gene is a candidate for encoding florigen. We show that the protein encoded by Hd3a, a rice ortholog of FT, moves from the leaf to the shoot apical meristem and induces flowering in rice. These results suggest that the Hd3a protein may be the rice florigen.

This paper presents a comparative analysis of traffic speed data on two-lane rural road segments using three different methods: radar technology measuring spot speeds, Google Maps API, and License Plate Recognition (LPR) providing space-mean speed estimates. The study employs a two-stage validation approach with LPR as the reference method, followed by direct comparison between Google Maps and radar speed data. Analysis of five road segments with varying geometry, traffic volumes, mobile signal quality, and radar placement reveals that no single method is universally superior. The findings show that Google Maps API offers a scalable, cost-effective solution with reasonable performance (MAE 5.5-8.8 km/h) under optimal conditions, but becomes unreliable in areas with weak mobile signal coverage and tends to smooth speed variations. When properly positioned, radar measurements provide high-resolution speed data with sensitivity to traffic changes (MAE 3.7-9.8 km/h against LPR), but their point-based nature creates significant dependency on sensor placement. Both methods exhibit reduced accuracy during low-speed conditions, as indicated by elevated MAPE values. Mobile network signal quality emerges as critical for Google Maps reliability, while road segment geometry and sensor positioning are paramount for radar reliability.

Multicellular organisms use mobile intercellular signals to generate spatiotemporal patterns of growth and differentiation. These signals, termed morphogens, arise from localized sources and move by diffusion or directional transport to be interpreted at target cells. The classical model for a morphogen is where a substance diffuses from a source to generate a concentration gradient that provides positional information across a field. This concept, presented by Wolpert and popularized as the "French Flag Model," remains highly influential, but other patterning models, which do not rely on morphogen gradients, also exist. Here, we review current evidence for mobile morphogenetic signals in plant root development and how they fit within existing conceptual frameworks for pattern formation. We discuss how the signals are formed, distributed, and interpreted in space and time, emphasizing the regulation of movement on the ability of morphogens to specify patterns. While significant advances have been made in the field since the first identification of mobile morphogenetic factors in plants, key questions remain to be answered, such as how morphogen movement is regulated, how these mechanisms allow scaling in different species, and how morphogens act to enable plant regeneration in response to damage.

Plants produce diverse small molecules rapidly in response to localized pathogenic attack. Some of the molecules are able to migrate systemically as mobile signals, leading to the immune priming that protects the distal tissues against future infections by a broad-spectrum of invaders. Such form of defense is unique in plants and is known as systemic acquired resistance (SAR). There are many small molecules identified so far with important roles in the systemic immune signaling, some may have the potential to act as the mobile systemic signal in SAR establishment. Here, we summarize the recent advances in SAR research, with a focus on the role and mechanisms of different small molecules in systemic immune signaling.

Plant survival to a potential plethora of diverse environmental insults is underpinned by coordinated communication amongst organs to help shape effective responses to these environmental challenges at the whole plant level. This interorgan communication is supported by a complex signal network that regulates growth, development and environmental responses. Nitric oxide (NO) has emerged as a key signalling molecule in plants. However, its potential role in interorgan communication has only recently started to come into view. Direct and indirect evidence has emerged supporting that NO and related species (S-nitrosoglutathione, nitro-linolenic acid) are mobile interorgan signals transmitting responses to stresses such as hypoxia and heat. Beyond their role as mobile signals, NO and related species are involved in mediating xylem development, thus contributing to efficient root-shoot communication. Moreover, NO and related species are regulators in intraorgan systemic defence responses aiming an effective, coordinated defence against pathogens. Beyond its in planta signalling role, NO and related species may act as ex planta signals coordinating external leaf-to-leaf, root-to-leaf but also plant-to-plant communication. Here, we discuss these exciting developments and emphasise how their manipulation may provide novel strategies for crop improvement.

The Arabidopsis BYPASS1 (BPS1) gene is required for normal root and shoot development. In bps1 mutants, grafting and root excision experiments have shown that mutant roots produce a transmissible signal that is capable of arresting shoot development. In addition, we previously showed that growth of bps1 mutants on the carotenoid biosynthesis inhibitor fluridone resulted in partial rescue of both leaf and root defects. These observations suggest that a single mobile carotenoid-derived signal affects both root and shoot development. Here, we describe further characterization of the bps1 root-derived signal using genetic and biosynthetic inhibitor approaches. We characterized leaf and root development in double mutants that combined the bps1 mutant with mutants that have known defects in genes encoding carotenoid processing enzymes or defects in responses to carotenoid-derived abscisic acid. Our studies indicate that the mobile signal is neither abscisic acid nor the MAX-dependent hormone that regulates shoot branching, and that production of the signal does not require the activity of any single carotenoid cleavage dioxygenase. In addition, our studies with CPTA, a lycopene cyclase inhibitor, show that signal production requires synthesis of beta-carotene and its derivatives. Furthermore, we show a direct requirement for carotenoids as signal precursors, as the GUN plastid-to-nucleus signaling pathway is not required for phenotypic rescue. Together, our results suggest that bps1 roots produce a novel mobile carotenoid-derived signaling compound.

The growing demand for land mobile communication systems has opened new requirements for digital modulations with high spectral efficiency. Although efficient modulation types, namely higher ordered m-ary QAMs, have found use in terrestrial applications, the land mobile environment is considered too arduous for their use. The mobile signal at UHF is subject to multipath that results in a channel characterized by rapid variations of received amplitude and phase. We review the dynamic measures that characterize the effects of multipath on a land mobile communication signal and introduce a new measure, fractional power change rate. This is the rate at which multipath causes a change to the received power level. Just as the phase change rate defines the low-end modulation frequency response supportable by the channel, fractional power change rate defines the low-end rate at which the channel will support level changes in PAM or QAM. Characterization of these measures will provide the basic rates at which adaptive carrier recovery techniques compensate for effects of the varying channel. A model based directly on the multipath and receiver architecture is used to derive the distribution of the fractional power change rate, power change rate, and phase change rate. The model statistics are then compared to actual measurements to verify their applicability to the environment.