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Communication infrastructure is crucial during emergencies because it ensures reliable coordination and information dissemination for effective search and rescue missions. However, these systems rely on physical structures, making them vulnerable to failures caused by disasters like fires and flooding. To enhance resilience, redundant infrastructure is commonly practiced. For instance, redundant systems ensure continuous operation in space missions where repairs are not feasible. A major gap exists, however, as redundancy is not a viable solution for remote areas without existing communication infrastructure. Additionally, victims may need to evacuate to safety zones not covered by mainstream communication systems. In such cases, alternative infrastructure that is easy to deploy is required to address emergency communication challenges fully. This paper presents a framework to analyze the deployability of current satellite communication infrastructure for this purpose. The analysis focuses on deployability dynamics, elements, and applications. We start by discussing the evolution of satellite ground stations into mobile and software-defined systems. In the analysis, we find that, despite these advancements, current infrastructure fails to provide a single device that meets low power and low-cost rapid deployment requirements based on our deployability framework. The product that almost fulfils this is the satellite phone. However, satellite phones are prohibitively expensive for large-scale deployments, with a single device costing over 600 United States Dollars (USD), more than ten times the cost of Internet of Things (IoT) devices supporting similar technologies. Additionally, they are not power efficient. The high cost of satellite applications is associated with spectrum licensing and satellite infrastructural costs. We have analyzed satellite communication frequency bands and architectural design, such as antenna designs, communication protocols and standards, modulation techniques, and signal processing methods, to understand the important factors toward full deployability. Our comprehensive analysis reveals a gap in addressing interoperability issues caused by disparate communication standards, processing power and energy requirements. Further analysis reveals promising open-source initiatives that offer potential solutions, such as low-data rate modulation schemes, low-bitrate voice codecs, and low-power encryption techniques. Additionally, advancements in Artificial Intelligence(AI) and robust cybersecurity techniques provide a solid foundation for future developments of rapidly deployable satellite-based emergency communication infrastructure. Consequently, we have identified opportunities for developing low-power, frequency-agile architectures that integrate satellite and terrestrial network infrastructure. Specifically, the next-generation Cospas-Sarsat Search and Rescue system provides a pathway for eliminating spectrum licensing costs, making deployable systems affordable for mass adoption. Future work should leverage advancements in low-bitrate technologies to enhance emergency systems, ensuring secure and resilient two-way voice, messaging, and distress signalling capabilities for critical communications.

Abstract Background Scientific literature carries a wealth of information crucial for research, but only a fraction of it is present as structured information in databases and therefore can be analyzed using traditional data analysis tools. Natural language processing (NLP) is often and successfully employed to support humans by distilling relevant information from large corpora of free text and structuring it in a way that lends itself to further computational analyses. For this pilot, we developed a pipeline that uses NLP on biological literature to produce knowledge networks. We focused on the flesh color of potato, a well-studied trait with known associations, and we investigated whether these knowledge networks can assist us in formulating new hypotheses on the underlying biological processes. Results We trained an NLP model based on a manually annotated corpus of 34 full-text potato articles, to recognize relevant biological entities and relationships between them in text (genes, proteins, metabolites and traits). This model detected the number of biological entities with a precision of 97.65% and a recall of 88.91% on the training set. We conducted a time series analysis on 4023 PubMed abstract of plant genetics-based articles which focus on 4 major Solanaceous crops (tomato, potato, eggplant and capsicum), to determine that the networks contained both previously known and contemporaneously unknown leads to subsequently discovered biological phenomena relating to flesh color. A novel time-based analysis of these networks indicates a connection between our trait and a candidate gene (zeaxanthin epoxidase) already two years prior to explicit statements of that connection in the literature. Conclusions Our time-based analysis indicates that network-assisted hypothesis generation shows promise for knowledge discovery, data integration and hypothesis generation in scientific research.

Este artículo investiga los esfuerzos de los cusqueños para fomentar el turismo después del terremoto de 1950. Sobre todo, cómo los cusqueños usaron los fondos de restauración para desarrollar el turismo en una época cuando el gobierno nacional no respaldaba iniciativas estatales para lograr el desarrollo en el sur andino peruano. Los cusqueños usaron los recursos de instituciones dedicadas a la reconstrucción de la ciudad después del terremoto. Entidades como la Junta de Reconstrucción y Fomento Industrial del Cuzco, la Corporación de Reconstrucción y Fomento de Cuzco (CRYF), y la UNESCO. Esto para sostener el desarrollo del turismo en la región. Sin embargo, este artículo investiga las consecuencias negativas de estas políticas del turismo. Por ejemplo, se ejecutaron restauraciones controversiales en sitios arqueológicos, sobre todo en Machu Picchu. También, al priorizar el turismo, la élite cusqueña ignoró la crisis agraria que se desarrollaba en la región

Covert communication techniques play a crucial role in military and commercial applications to maintain the privacy and security of wireless transmissions from prying eyes. These techniques ensure that adversaries cannot detect or exploit the existence of such transmissions. Covert communications, also known as low probability of detection (LPD) communication, are instrumental in preventing attacks such as eavesdropping, jamming, or interference that could compromise the confidentiality, integrity, and availability of wireless communication. Direct-sequence spread-spectrum (DSSS) is a widely used covert communication scheme that expands the bandwidth to mitigate interference and hostile detection effects, reducing the signal power spectral density (PSD) to a low level. However, DSSS signals possess cyclostationary random properties that an adversary can exploit using cyclic spectral analysis to extract useful features from the transmitted signal. These features can then be used to detect and analyse the signal, making it more susceptible to electronic attacks such as jamming. To overcome this problem, a method to randomise the transmitted signal and reduce its cyclic features is proposed in this paper. This method produces a signal with a probability density function (PDF) similar to thermal noise, which masks the signal constellation to appear as thermal white noise to unintended receivers. This proposed scheme, called Gaussian distributed spread-spectrum (GDSS), is designed such that the receiver does not need to know any information about the thermal white noise used to mask the transmit signal to recover the message. The paper presents the details of the proposed scheme and investigates its performance in comparison to the standard DSSS system. This study used three detectors, namely, a high-order moments based detector, a modulation stripping detector, and a spectral correlation detector, to evaluate the detectability of the proposed scheme. The detectors were applied to noisy signals, and the results revealed that the moment-based detector failed to detect the GDSS signal with a spreading factor, N = 256 at all signal-to-noise ratios (SNRs), whereas it could detect the DSSS signals up to an SNR of −12 dB. The results obtained using the modulation stripping detector showed no significant phase distribution convergence for the GDSS signals, similar to the noise-only case, whereas the DSSS signals generated a phase distribution with a distinct shape, indicating the presence of a valid signal. Additionally, the spectral correlation detector applied to the GDSS signal at an SNR of −12 dB showed no identifiable peaks on the spectrum, providing further evidence of the effectiveness of the GDSS scheme and making it a favourable choice for covert communication applications. A semi-analytical calculation of the bit error rate is also presented for the uncoded system. The investigation results show that the GDSS scheme can generate a noise-like signal with reduced identifiable features, making it a superior solution for covert communication. However, achieving this comes at a cost of approximately 2 dB on the signal-to-noise ratio.

Excerpt from Dean Worcester’s Fantasy Islands: Photography, Film, and the Colonial Philippines (University of Michigan Press, 2014)

Gulf War Illness (GWI) is a chronic multi-symptom disorder affecting up to one-third of the 700,000 returning veterans of the 1991 Persian Gulf War and for which there is no known cure. GWI symptoms span several of the body's principal regulatory systems and include debilitating fatigue, severe musculoskeletal pain, cognitive and neurological problems. Using computational models, our group reported previously that GWI might be perpetuated at least in part by natural homeostatic regulation of the neuroendocrine-immune network. In this work, we attempt to harness these regulatory dynamics to identify treatment courses that might produce lasting remission. Towards this we apply a combinatorial optimization scheme to the Monte Carlo simulation of a discrete ternary logic model that represents combined hypothalamic-pituitary-adrenal (HPA), gonadal (HPG), and immune system regulation in males. In this work we found that no single intervention target allowed a robust return to normal homeostatic control. All combined interventions leading to a predicted remission involved an initial inhibition of Th1 inflammatory cytokines (Th1Cyt) followed by a subsequent inhibition of glucocorticoid receptor function (GR). These first two intervention events alone ended in stable and lasting return to the normal regulatory control in 40% of the simulated cases. Applying a second cycle of this combined treatment improved this predicted remission rate to 2 out of 3 simulated subjects (63%). These results suggest that in a complex illness such as GWI, a multi-tiered intervention strategy that formally accounts for regulatory dynamics may be required to reset neuroendocrine-immune homeostasis and support extended remission.

When the US acquired its colonies of Puerto Rico and the Philippines in the aftermath of the 1898 war with Spain, those colonies had to be made known to American citizens. Lanny Thompson has described what he calls the “principle narratives” of the different colonies, and the ways that those narratives helped shape political debates about those colonies. Thompson notes that photography played an instrumental role in developing and representing those narratives. “Colonial Photography Across Empires and Islands” discusses the specific uses of photography in the US colonial regimes in the Philippines and Puerto Rico, the two colonies most frequently deemed “unfit” for self-rule. It traces the contours of those themes and ideas that were shared across the different colonies, as well as the particular subject matter that photographers were attracted to in each colony. It also finds points of connection and continuity between US colonial photography, and photography in the Philippines in the Spanish colonial era. The triangulation of these three colonial contexts helps clarify both the generalized nature of colonial photography and the specific uses of photography in particular colonial contexts.

A cada dia surgem mais provas da importância da inovação radical ou revolucionária na determinação do sucesso das empresas, em longo prazo, no mercado competitivo atual. Embora esse reconhecimento tenha estado presente em muitas empresas sólidas, existem dúvidas no que diz respeito à maneira segundo a qual a inovação deve ser implementada. O presente artigo baseia-se em um estudo longitudinal de 12 projetos de inovação radical em 10 empresas maduras de grande porte, no período de seis anos. O ciclo de vida dos projetos de inovação radical é diferente daquele de projetos incrementais, devido ao grande número de incertezas e descontinuidades. Tais características exigem que os projetos de inovação radical sejam gerenciados de forma diversa daquela aplicada aos projetos incrementais. Demonstramos sete fatores estratégicos decisivos para realizar-se a implementação bem-sucedida da inovação radical.