Hasil untuk "Miscellaneous systems and treatments"

Jung Hwa Lim, Hyun Mi Kang, Cho-Rok Jung

Rho-associated coiled-coil containing protein kinase (ROCK) signaling is a primary regulator of cell behavior in stem cell biology and organoid systems. This review examines the diverse roles of Rho/ROCK signaling in cytoskeletal remodeling, cell adhesion, differentiation, and mechanotransduction. Special emphasis is placed on its role in organoid formation, patterning, and functional maturation. An understanding of how this pathway integrates with other signaling networks, such as Ras, Hippo, and PI3K-AKT, is crucial for optimizing organoid fidelity. We propose future research directions that enhance organoid models through targeted modulation of ROCK activity, thereby opening new opportunities for regenerative medicine and disease modeling.

Luca Ballotta, Nicola Bastianello, Riccardo M. G. Ferrari et al.

In this paper, we address two practical challenges of distributed learning in multi-agent network systems, namely personalization and resilience. Personalization is the need of heterogeneous agents to learn local models tailored to their own data and tasks, while still generalizing well; on the other hand, the learning process must be resilient to cyberattacks or anomalous training data to avoid disruption. Motivated by a conceptual affinity between these two requirements, we devise a distributed learning algorithm that combines distributed gradient descent and the Friedkin-Johnsen model of opinion dynamics to fulfill both of them. We quantify its convergence speed and the neighborhood that contains the final learned models, which can be easily controlled by tuning the algorithm parameters to enforce a more personalized/resilient behavior. We numerically showcase the effectiveness of our algorithm on synthetic and real-world distributed learning tasks, where it achieves high global accuracy both for personalized models and with malicious agents compared to standard strategies.

Jinwei Hu, Zezhi Tang, Xin Jin et al.

This paper presents HERO (Hierarchical Testing with Rabbit Optimization), a novel black-box adversarial testing framework for evaluating the robustness of deep learning-based Prognostics and Health Management systems in Industrial Cyber-Physical Systems. Leveraging Artificial Rabbit Optimization, HERO generates physically constrained adversarial examples that align with real-world data distributions via global and local perspective. Its generalizability ensures applicability across diverse ICPS scenarios. This study specifically focuses on the Proton Exchange Membrane Fuel Cell system, chosen for its highly dynamic operational conditions, complex degradation mechanisms, and increasing integration into ICPS as a sustainable and efficient energy solution. Experimental results highlight HERO's ability to uncover vulnerabilities in even state-of-the-art PHM models, underscoring the critical need for enhanced robustness in real-world applications. By addressing these challenges, HERO demonstrates its potential to advance more resilient PHM systems across a wide range of ICPS domains.

Gabriela Gomes da Rocha, Karine Anusca Martins

Introdução: A obrigatoriedade da compra de, no mínimo, 30% do repasse do Fundo Nacional de Desenvolvimento da Educação (FNDE) em gêneros alimentícios provenientes da agricultura familiar para o Programa Nacional de Alimentação Escolar (PNAE), representou uma boa estratégia de incentivo a melhores hábitos alimentares na escola e melhoria na renda de pequenos agricultores. Objetivo: Analisar a relação entre o número de Declarações de Aptidão (DAP) ativas ao Programa Nacional de Fortalecimento da Agricultura Familiar (PRONAF) e a comercialização para o PNAE em municípios goianos. Metodologia: Trata-se de estudo transversal descritivo com análise de dados secundários disponíveis no Portal Brasileiro de Dados Abertos e do Sistema de Gestão de Prestação de Contas (SiGPC). Os dados foram coletados no período de março a outubro de 2021 e referem-se ao ano de 2019. Foram realizadas análises estatísticas descritivas. Resultados: Os resultados demonstraram que 74,1% das cidades goianas realizaram a compra da agricultura familiar e, destes, 54,3% adquiriram, pelo menos, 30% de gêneros alimentícios diretamente da agricultura familiar para o PNAE. Quanto ao número de DAP ativas do estado, obteve-se um total de 31.044, sendo 99,7% (n=30.941) do agricultor (pessoa física). A distribuição de DAP pessoa física se mostrou relativamente homogênea (acima de 80%) entre as mesorregiões do estado, sendo maior na Leste. Conclusão: Apesar da maior parte dos municípios de Goiás realizar, em 2019, a compra da alimentação escolar pela agricultura familiar, por meio de DAF pessoa física, o percentual mínimo exigido nesse processo de comercialização pela Lei no 11.947/2009 foi cumprido por 54,3% destes municípios. Ações de educação permanente com todos os atores sociais envolvidos na execução do PNAE e uma maior integração com os agricultores familiares, promovendo estratégias de capacitação técnica em parcerias intersetoriais, são recomendadas. Pesquisas complementares devem ser estimuladas pelas universidades regionais.  

Mengyuan Hu, Xiaowen Zhang, Xuya Zhang et al.

Objective: To evaluate the effectiveness and safety of modified Xiaoyao powder for postpartum depression (PPD) by conducting a systematic review of randomized controlled trials (RCTs). Methods: The Chinese National Knowledge Infrastructure Databases (CNKI), the Chinese Scientific Journals Database (VIP), Wanfang, Google Scholar, the SinoMed, Embase, Cochrane Library, and PubMed databases were searched from their inception to April 25, 2023. The Cochrane Risk of Bias tool was used to assess the quality of the trials. We applied the risk ratio to present dichotomous data and the mean difference to present continuous data. Data with similar characteristics were pooled for meta-analysis and heterogeneity was assessed using I2. Results: This review included 35 trials involving 2848 participants. The quality of the included studies was low (unclear randomization processes and insufficient reporting of blinding). Participants treated with modified Xiaoyao powder plus Western medicine showed lower Hamilton Depression Scale (HAMD) depression score than those who used Western medicine alone (mean difference = −2.15; 95% confidence interval:−2.52 to 1.78; P < .00001), and higher effective rate (relative risk = 1.19; 95% confidence interval: 1.15 to 1.24; P < .00001), When comparing modified Xiaoyao alone with Western medicine, the HAMD depression score remained low, however, the efficacy rate was higher in the modified Xiaoyao group. Regarding adverse events, the modified Xiaoyao group reported weight gain, nausea, and diarrhea, but no severe adverse events were reported. Conclusion: Modified Xiaoyao may help relieve depression in PPD when used alone or in combination with Western medicine, with minor side effects. Therefore, future high-quality, large-sample size RCTs are warranted.

Christine P Lee

My research centers on the development of context-adaptive AI systems to improve end-user adoption through the integration of technical methods. I deploy these AI systems across various interaction modalities, including user interfaces and embodied agents like robots, to expand their practical applicability. My research unfolds in three key stages: design, development, and deployment. In the design phase, user-centered approaches were used to understand user experiences with AI systems and create design tools for user participation in crafting AI explanations. In the ongoing development stage, a safety-guaranteed AI system for a robot agent was created to automatically provide adaptive solutions and explanations for unforeseen scenarios. The next steps will involve the implementation and evaluation of context-adaptive AI systems in various interaction forms. I seek to prioritize human needs in technology development, creating AI systems that tangibly benefit end-users in real-world applications and enhance interaction experiences.

Thach Ngoc Dinh, Gia Quoc Bao Tran

This work proposes an interval observer design for nonlinear discrete-time systems based on the Kazantzis-Kravaris/Luenberger (KKL) paradigm. Our design extends to generic nonlinear systems without any assumption on the structure of its dynamics and output maps. Relying on a transformation putting the system into a target form where an interval observer can be directly designed, we then propose a method to reconstruct the bounds in the original coordinates using the bounds in the target coordinates, thanks to the Lipschitz injectivity of this transformation achieved under Lipschitz distinguishability when the target dynamics have a high enough dimension and are pushed sufficiently fast. An academic example serves to illustrate our methods.

Arthur N. Montanari, Chao Duan, Adilson E. Motter

The duality between controllability and observability enables methods developed for full-state control to be applied to full-state estimation, and vice versa. In applications in which control or estimation of all state variables is unfeasible, the generalized notions of output controllability and functional observability establish the minimal conditions for the control and estimation of a target subset of state variables, respectively. Given the seemly unrelated nature of these properties, thus far methods for target control and target estimation have been developed independently in the literature. Here, we characterize the graph-theoretic conditions for target controllability and target observability (which are, respectively, special cases of output controllability and functional observability for structured systems). This allow us to rigorously establish a weak and strong duality between these generalized properties. When both properties are equivalent (strongly dual), we show that efficient algorithms developed for target controllability can be used for target observability, and vice versa, for the optimal placement of sensors and drivers. These results are applicable to large-scale networks, in which control and monitoring are often sought for small subsets of nodes.

Guglielmo Frigo, Paolo Attilio Pegoraro, Sergio Toscani

Fast dynamics and transient events are becoming more and more frequent in power systems, due to the high penetration of renewable energy sources and the consequent lack of inertia. In this scenario, Phasor Measurement Units (PMUs) are expected to track the monitored quantities. Such functionality is related not only to the PMU accuracy (as per the IEC/IEEE 60255-118-1 standard) but also to the PMU reporting rate (RR). High RRs allow tracking fast dynamics, but produce many redundant measurement data in normal conditions. In view of an effective tradeoff, the present paper proposes an adaptive RR mechanism based on a real-time selection of the measurements, with the target of preserving the information content while reducing the data rate. The proposed method has been tested considering real-world datasets and applied to four different PMU algorithms. The results prove the method effectiveness in reducing the average data throughput as well as its scalability at PMU concentrator or storage level.

Mahshid Ghanbari, Mohammad Shokrzadeh Lamuki, Emran Habibi et al.

Objectives: Insulin resistance (IR) is major cause of type 2 diabetes (T2D), and adipokines (e.g., adiponectin, leptin, and resistin) play an important role in insulin sensitivity. Medicinal plants are frequently used for T2D treatment. This study investigates the effect of Artemisia annua L. (AA) extracts on adipokines in mice with high-fat-diet (HFD)/streptozotocin (STZ)-induced T2D.Methods : : We divided 60 mice into 12 groups (n = 5 per group): control, untreated T2D, treated T2D, and 9 other groups. T2D was induced in all groups, except controls, by 8 weeks of HFD and STZ injection. The treated T2D group was administered 250 mg/kg of metformin (MTF), while the nine other groups were treated with 100, 200, and 400 mg/kg of hot-water extract (HWE), cold-water extract (CWE), and alcoholic extract (ALE) of AA (daily oral gavage) along with 250 mg/kg of MTF for 4 weeks. The intraperitoneal glucose tolerance test (IPGTT) was performed, and the homeostasis model assessment of adiponectin (HOMA-AD) index and blood glucose and serum insulin, leptin, adiponectin, and resistin levels were measured.Results : : Similar to MTF, all three types of AA extracts (HWEs, CWEs, and ALEs) significantly (p < 0.0001) decreased the area under the curve (AUC) of glucose during the IPGTT, the HOMA-AD index, blood glucose levels, and serum insulin, leptin, and resistin levels and increased serum adiponectin levels in the MTF group compared to the T2D group (p < 0.0001). The HWEs affected adipokine release, while the CWEs and ALEs decreased leptin and resistin production.Conclusion : : Water and alcoholic AA extracts have an antihyperglycemic and antihyperinsulinemic effect on HFD/STZ diabetic mice. In addition, they decrease IR by reducing leptin and resistin production and increasing adiponectin secretion from adipocytes.

Marim Ibrahim, Joseph Therriault, Vasavan P Nair et al.

Background: Among a rapidly aging population, there is increased need for neuroprotective interventions promoting healthy neurological aging. Mind-body interventions, such as Kundalini yoga, are actively being explored as accessible means to encourage healthy aging. However, little remains known about the neurobiological effects of Kundalini yoga. Aims: This pilot randomized-controlled trial (RCT) examined the potential neuroprotective effects of Kundalini yoga in older adults. Methods: We conducted an RCT with 11 healthy meditation-naïve older adults. Participants were randomized to a Kundalini yoga or psychoeducation intervention. Structural magnetic resonance imaging data were obtained at baseline and 12-week follow-up. The primary outcome measure was gray matter volume of the bilateral hippocampi and bilateral posterior cingulate cortex. Results: We found significant right hippocampal volume increases specific to the Kundalini yoga group (P = 0.034, ηp2 = 0.408). Conclusions: These findings provide initial neurobiological support for the neuroprotective effects of Kundalini yoga.

Su Yeon Seo, Soo Phil Kim, Se Kyun Bang et al.

Background: Most ETOH addiction preclinical studies have focused on the rewards of chronic ETOH self-administration or the ETOH reinstatement model. Acute ETOH administration studies are scarce despite the potential of ETOH to cause sedation, intoxication and reduced acute functional tolerance. Here, we established a rat model of acute ETOH administration induced by an intraperitoneal injection of 1 g/kg ethanol and assessed the similarities in physiological and behavioral effects between acupuncture and Sigma1 R antagonists. Methods: Male Wistar rats (300−330 g) received pretreatment with (1) saline injection, (2) saline + mechanical stimulation using a mechanical acupuncture instrument (MAI) for acupuncture at the Shenmen (HT7), (3) ETOH (1 g/kg) injection, (4) ETOH + HT7, or (5) the selective σ1 R antagonist BD 1047 (3, 10, or 30 mg/kg, intraperitoneal (IP) injection). ETOH (1 g/kg) or saline was IP injected after 10 min. Then, ETOH-induced immobility was evaluated in an open field arena, ultrasonic vocalizations (USVs) indicating ethanol-induced emotional changes were recorded in a recording chamber, and the rats were sacrificed for the analysis of protein levels of σ1 R in several regions of the brain. Results: Acute ethanol exposure increased the immobile time, 22-kHz USVs, and protein levels of σ1 R in the ventral tegmental area (VTA). However, pretreatment with acupuncture at HT7 induced recovery of immobile time, reduced 22-kHz USVs, and regulated the protein levels of σ1 R in the VTA. These effects have similarities with IP injection of BD 1047 (10 mg/kg). Conclusion: This study showed that acupuncture at HT7 regulates immobility and 22-kHz USVs via Sigma1 R in the VTA upon acute ETOH exposure.

Zahra Bagheri, Azim Azizi, Khodayar Oshvandi et al.

Objectives: Bruising is an important side effect of enoxaparin injection. Comfrey (Symphytum officinale) is used to treat different types of wounds, bone fractures, and bruising in traditional medicine in many countries for centuries. This study aimed to determine the effects of the Comfrey ointment on the bruise size and color following enoxaparin injection. Methods : This double-blind randomized clinical trial was conducted on 80 patients with acute coronary syndrome (ACS). The participants were randomly divided into two groups of 40, namely Comfrey and Placebo. Changes in bruise size and color in both groups were assessed daily before and after the intervention. Results : The Comfrey and Placebo groups were homogeneous in demographic and clinical variables. A downward trend was observed in the bruise size in both groups throughout the study. However, the bruise size was smaller in the Comfrey group than the Placebo group on day 2-5 of the intervention. Moreover, there was a significant difference in bruise color between the groups, with a shorter healing course in the Comfrey group. Conclusion : The Comfrey ointment accelerated the healing process of enoxaparin injection-induced bruising in patients with ACS. It is recommended as a safe and simple approach for these patients.

Seul Woo Leem, Min Kyeong Kim, Seo Lim Ko et al.

This study aimed to analyze the use of Korean medicine treatments for alopecia in among clinical studies. We identified and analyzed 22 studies from Korean databases; Oriental Medicine Advanced Searching Integrated System (OASIS), Science ON, Korean Studies Information Service System (KISS), and Research Information Sharing Service (RISS) and international database; PubMed. We analyzed the Korean medical treatment in each case and determined the tendency to use each intervention. We analyzed 1,464 patients from 22 selected studies. Herbal medicine, acupuncture, external medicine or products, pharmacopuncture, and phototherapy were used for alopecia treatment. The herbal medicines mainly used to treat alopecia were Gagam Cheongyoung-tang, Gagam Hwajung-hwan, and Yukmijihwang-tang·hwan. The acupoints primarily used were GV20, EX-HN1, GB5, KI3, PC6, ST36, GV22, and A-shi. The most commonly used pharmacopuncture therapies were Hwangryunhaedoktang (HH), Carthami Fructus (CF), Bee Venom (BV), and Hominis placenta (HP). The Korean medical treatment for alopecia improved the condition of patients. However, seven studies reported the occurrence of side effects such as pruritus, dazed, drowsiness, headache, pain, and diarrhea. This study shows the potential of Korean medicine for the treatment of alopecia. Further studies with a large sample size and long-term follow-up are warranted to establish the primary treatment guidelines and objective out-come measures for alopecia.

Yong Kiam Tan, André Platzer

Real world systems of interest often feature interactions between discrete and continuous dynamics. Various hybrid system formalisms have been used to model and analyze this combination of dynamics, ranging from mathematical descriptions, e.g., using impulsive differential equations and switching, to automata-theoretic and language-based approaches. This paper bridges two such formalisms by showing how various classes of switched systems can be modeled using the language of hybrid programs from differential dynamic logic (dL). The resulting models enable the formal specification and verification of switched systems using dL and its existing deductive verification tools such as KeYmaera X. Switched systems also provide a natural avenue for the generalization of dL's deductive proof theory for differential equations. The completeness results for switched system invariants proved in this paper enable effective safety verification of those systems in dL.

Jun Hong Park, Sueun Lee, Jin Mi Chun

Brendan Patch, Bert Zwart

We propose a method for determining the most likely cause, in terms of conventional generator outages and renewable fluctuations, of power system frequency reaching a predetermined level that is deemed unacceptable to the system operator. Our parsimonious model of system frequency incorporates primary and secondary control mechanisms, and supposes that conventional outages occur according to a Poisson process and renewable fluctuations follow a diffusion process. We utilize a large deviations theory based approach that outputs the most likely cause of a large excursion of frequency from its desired level. These results yield the insight that current levels of renewable power generation do not significantly increase system vulnerability in terms of frequency deviations relative to conventional failures. However, for a large range of model parameters it is possible that such vulnerabilities may arise as renewable penetration increases.

Jian Wang, Yongxin Liu, Houbing Song

Unmanned aircraft systems (UAS), or unmanned aerial vehicles (UAVs), often referred to as drones, have been experiencing healthy growth in the United States and around the world. The positive uses of UAS have the potential to save lives, increase safety and efficiency, and enable more effective science and engineering research. However, UAS are subject to threats stemming from increasing reliance on computer and communication technologies, which place public safety, national security, and individual privacy at risk. To promote safe, secure and privacy-respecting UAS operations, there is an urgent need for innovative technologies for detecting, tracking, identifying and mitigating UAS. A Counter-UAS (C-UAS) system is defined as a system or device capable of lawfully and safely disabling, disrupting, or seizing control of an unmanned aircraft or unmanned aircraft system. Over the past 5 years, significant research efforts have been made to detect, and mitigate UAS: detection technologies are based on acoustic, vision, passive radio frequency, radar, and data fusion; and mitigation technologies include physical capture or jamming. In this paper, we provide a comprehensive survey of existing literature in the area of C-UAS, identify the challenges in countering unauthorized or unsafe UAS, and evaluate the trends of detection and mitigation for protecting against UAS-based threats. The objective of this survey paper is to present a systematic introduction of C-UAS technologies, thus fostering a research community committed to the safe integration of UAS into the airspace system.

Colin Shea-Blymyer, Houssam Abbas

We consider the pressing question of how to model, verify, and ensure that autonomous systems meet certain \textit{obligations} (like the obligation to respect traffic laws), and refrain from impermissible behavior (like recklessly changing lanes). Temporal logics are heavily used in autonomous system design; however, as we illustrate here, temporal (alethic) logics alone are inappropriate for reasoning about obligations of autonomous systems. This paper proposes the use of Dominance Act Utilitarianism (DAU), a deontic logic of agency, to encode and reason about obligations of autonomous systems. We use DAU to analyze Intel's Responsibility-Sensitive Safety (RSS) proposal as a real-world case study. We demonstrate that DAU can express well-posed RSS rules, formally derive undesirable consequences of these rules, illustrate how DAU could help design systems that have specific obligations, and how to model-check DAU obligations.

Nicola Viafora, Stefanos Delikaraoglou, Pierre Pinson et al.

The large shares of wind power generation in electricity markets motivate higher levels of operating reserves. However, current reserve sizing practices fail to account for important topological aspects that might hinder their deployment, thus resulting in high operating costs. Zonal reserve procurement mitigates such inefficiencies, however, the way the zones are defined is still open to interpretation. This paper challenges the efficiency of predetermined zonal setups that neglect the location of stochastic power production in the system, as well as the availability, cost and accessibility of flexible generating units. To this end, we propose a novel reserve procurement approach, formulated as a two-stage stochastic bilevel model, in which the upper level identifies a number of contiguous reserve zones using dynamic grid partitioning and sets zonal requirements based on the total expected operating costs. Using two standard IEEE reliability test cases, we show how the efficient partitioning of reserve zones can reduce expected system cost and promote the integration of stochastic renewables.