Physical Isolation Research Articles

Live in new normal. Space envision under post-pandemic

The arrival of the pandemic changed the peaceful lives of human beings, with many things that were taken for granted becoming difficult to do or prohibited. It redefined the relationship between safety and danger, private and public, and changed people's daily lives and habits. But while the pandemic brought negative aspects such as illness, panic, injury, and isolation, it also prompted more communication and understanding among people, pushing people to use a variety of approaches to integrate into this new public environment with protection for each individual and to find appropriate modes of getting along to explore the boundaries and transformations of the space. Under the rules and policies of segregation, a new consensus is gradually emerging in society. Distance is becoming a non-two-dimensional label, but a two-way transformation between psychological separation and physical isolation which are opposite but inter-flowing. How to define private and public space in the new living model, to realize communication and balance is the main topic of this project.

Physical Isolation of Single Protein Molecules within Well‐Defined Coordination Cages to Enhance Their Stability

Encapsulation of a single protein within a confined space can lead to distinct properties compared to bulk solutions, but controlling the number of encapsulated proteins and their environment remains challenging. This study demonstrates the encapsulation of single proteins within well‐defined, tunable cavities of self‐assembled coordination cages, thereby enhancing protein stability. Within uniform cavities of size‐tunable coordination cages, 15 different proteins of varying sizes (3‐6 nm in diameter) and properties (e.g., isoelectric points and hydrophobicity) were successfully confined. Various analytical techniques confirmed that the proteins maintained their secondary structures and enzymatic activities under denaturing conditions such as exposure to organic solvents, heat, and buffers. These findings suggest that such coordination cages have the potential to serve as synthetic hosts for precisely controlling protein functions within their customizable cavities.

Physical Isolation of Single Protein Molecules within Well-Defined Coordination Cages to Enhance Their Stability.

Encapsulation of a single protein within a confined space can lead to distinct properties compared to bulk solutions, but controlling the number of encapsulated proteins and their environment remains challenging. This study demonstrates the encapsulation of single proteins within well-defined, tunable cavities of self-assembled coordination cages, thereby enhancing protein stability. Within uniform cavities of size-tunable coordination cages, 15 different proteins of varying sizes (3-6 nm in diameter) and properties (e.g., isoelectric points and hydrophobicity) were successfully confined. Various analytical techniques confirmed that the proteins maintained their secondary structures and enzymatic activities under denaturing conditions such as exposure to organic solvents, heat, and buffers. These findings suggest that such coordination cages have the potential to serve as synthetic hosts for precisely controlling protein functions within their customizable cavities.

Commodity risk assessment of Petunia spp. and Calibrachoa spp. unrooted cuttings from Costa Rica.

The European Commission requested the EFSA Panel on Plant Health to evaluate the probability of entry of pests (likelihood of pest freedom at entry), including both regulated and non-regulated pests, associated with unrooted cuttings of the genera Petunia and Calibrachoa produced under physical isolation in Costa Rica. The relevance of any pest for this opinion was based on evidence collected according to specific criteria, following the methodology used for high-risk plants adapted for the specificity of this assessment. Twenty-two EU regulated pests (beet curly top virus, Bemisia tabaci, Chloridea virescens, Eotetranychus lewisi, Epitrix cucumeris, Epitrix tuberis, euphorbia mosaic virus, Helicoverpa zea, Liriomyza huidobrensis, Liriomyza sativae, Liriomyza trifolii, pepper golden mosaic virus, potato spindle tuber viroid, Ralstonia pseudosolanacearum, Ralstonia solanacearum, Spodoptera ornithogalli, squash leaf curl virus, Thrips palmi, tomato golden mosaic virus, tomato leaf curl Sinaloa virus, tomato spotted wilt virus, tomato yellow leaf curl virus) and one pest that is not regulated in the EU (Aleurodicus dispersus) fulfilled all relevant criteria and were selected for further evaluation. For these pests, the risk mitigation measures proposed in the technical dossier from Costa Rica were evaluated taking into account possible factors limiting their efficacies. Additionally, an expert judgement is given on the likelihood of pest freedom taking into consideration the risk mitigation measures acting on the pest, including uncertainties associated with the assessment. The estimated degree of pest freedom varies among the pests evaluated, with tomato spotted wilt virus being the pest most frequently expected on the imported cuttings. The expert knowledge elicitation indicated, with 95% certainty that between 9927 and 10,000 bags containing unrooted cuttings of Petunia spp. and Calibrachoa spp. per 10,000 would be free of tomato spotted wilt virus.

Resilience Practices in Health Science and Medical Libraries During the Early Stages of the COVID-19 Pandemic

This paper uses the concept of resilience engineering as an organizing principle to discuss best practices that evolved within health science/medical libraries in the United States during COVID-19 crisis, focusing on the period March – August 2020. Protection of library staff, assistance to medical staff, reducing the circulation of misinformation and public health consumerism all required substantial changes to standard processes. These process changes had to arise in the context of both physical isolation and information overload. Some practices became widespread due to their utility, and these are the focus of this report.

Evaluation of physical and chemical isolation methods to extract and purify Campylobacter jejuni extracellular polymeric substances.

The pathogenic bacterium Campylobacter jejuni is a major food safety concern as it can form biofilms that increase its survival and infective potential. Biofilms consist of microbial cells and extracellular matrix (ECM), which is made of water and extracellular polymeric substances (EPS), which are critical for structural integrity and pathogenicity. The aim of this study was to optimize a protocol for the isolation of C. jejuni ECM. We employed eight physical and chemical isolation methods to extract and purify ECM, followed by different qualitative and quantitative analyses using gel electrophoresis and spectroscopy. This comprehensive approach enabled the evaluation of ECM composition in terms of polysaccharides, proteins, and extracellular DNA. The isolation methods resulted in different yields and purities of the extracted ECM components. Centrifugation in combination with chemical treatments proved to be most effective, isolating higher concentrations of polysaccharides and proteins. Additionally, extraction with ether solution facilitated the recovery of high-molecular-weight extracellular DNA. Overall, we provide a refined methodology for ECM extraction from C. jejuni. As polysaccharides and proteins participate in biofilm stability and microbial communication, and extracellular DNA participates in genetic exchange and virulence, our study contributes towards a better understanding of the persistence of this pathogen in the food industry.

Distributional justice and climate risk assessment: An analysis of disparities within direct and indirect risk.

Climate change and natural hazard risk assessments often overlook indirect impacts, leading to a limited understanding of the full extent of risk and the disparities in its distribution across populations. This study investigates distributional justice in natural hazard impacts, exploring its critical implications for environmental justice, equity, and resilience in adaptation planning. We employ high-resolution spatial risk assessment and origin-destination routing to analyze coastal flooding and sea-level rise scenarios in Aotearoa New Zealand. This approach allows the assessment of both direct impacts (property exposure) and indirect impacts (physical isolation from key amenities) on residents. Indirect impacts, such as isolation and reduced access to resources, have significant adverse effects on well-being, social cohesion, and community resilience. Including indirect impacts in risk assessments dramatically increases the overall population burden, while revealing complex effects on existing inequalities. Our analysis reveals that including indirect impacts increases the overall population burden, but the effect on inequalities varies. These inequalities can be exacerbated or attenuated depending on scale and location, underscoring the need for decision-makers to identify these nuanced distributions and apply context-specific frameworks when determining equitable outcomes. Our findings uncover a substantial number of previously invisible at-risk residents-from 61,000 to 217,000 nationally in a present-day event-and expose a shift in impact distribution toward underserved communities. As indirect risks exacerbate disparities and impede climate adaptation efforts, adopting an inclusive approach that accounts for both direct and indirect risks and their [un]equal distribution is imperative for effective and equitabledecision-making.

Navigating integration challenges: Insights from migrant dairy farm workers in New Zealand

As the global demand for milk products continues to increase and dairy sectors become more concentrated, a pressing question arises: who will milk the cows and where will they come from? Mirroring global trends, the New Zealand dairy industry has experienced significant structural changes, with a shift from family-run dairy farms to larger commercially orientated operations. At the same time, domestic socio-economic and demographic changes have resulted in rural to urban migration. These factors have contributed to a shortage of skilled labour in some regions. To meet its labour demands, the New Zealand dairy sector has relied increasingly heavily on temporary migrant workers, who face significant challenges integrating into their new communities. This study uses data from in-depth interviews with 25 migrant dairy farm workers in Canterbury, New Zealand, and a modified conceptual framework for integration developed by Ager and Strang to enhance our understanding of how skilled migrants in the dairy sector adapt to unfamiliar host communities. Through thematic analysis we identify the factors that either facilitate or hinder the successful integration of this important but vulnerable group. Key themes include motivations for moving to New Zealand, pathways to obtaining their positions, and the primary challenges that they experience in attempting to integrate. Challenges include physical and social isolation, discrimination, and a lack of access to key services. As the agricultural sector continues to grow, it is essential to provide migrant farm workers with adequate support to ensure their successful social, cultural, and economic integration.

Digital voluntourism and sense of place: volunteers’ responsibility towards an ‘imaginary locality’

Digital volunteer tourism (DVT) has emerged as a viable alternative to positively impact destinations when travel is impossible during times of crisis. This leaves volunteers, the ‘agents’ in volunteer projects and development work, who might often identify with a destination or specific cause, without a tangible link to the locality. Raising the important question of what role being physically connected to the locality plays in voluntourism; this study focuses on volunteers’ perception of their own impact in an out-of-reach destination. Through online fieldwork during an eight-week internship with a volunteer organisation in Fiji, this paper offers first insights into the phenomenon of digital voluntourism by discussing the role that a link to the destination and a sense of place play in still feeling to be making a difference. Furthermore, this debate reveals whether and how DVT intends to stimulate a sense of belonging of those volunteers to foster their sense of responsibility, while juxtaposing these digital programmes to in-situ voluntourism. This paper, therefore, constitutes one of the first contributions conceptualising the geography of digital voluntourism, arguing that while DVT has its merits in contributing to the sustainable development agenda, the physical distance and isolation from the place where this impact should be felt compromise their feelings of achievement and understanding of the locality even more than in usual voluntourism projects.

Stigma relating to tuberculosis infection prevention and control implementation in rural health facilities in South Africa — a qualitative study outlining opportunities for mitigation

BackgroundTuberculosis (TB) is a stigmatised disease with intersectional associations with poverty, HIV, transmission risk and mortality. The use of visible TB infection prevention and control (IPC) measures, such as masks or isolation, can contribute to stigma.MethodsTo explore stigma in this condition, we conducted in-depth individual interviews with 18 health workers and 15 patients in the rural Eastern Cape of South Africa using a semi-structured interview guide and narrative approach. We used reflexive thematic analysis guided by line-by-line coding. We then interpreted these key findings using Link and Phelan’s theoretical model of stigma, related this to stigma mitigation recommendations from participants and identified levels of intervention with the Health Stigma and Discrimination Framework.ResultsParticipants shared narratives of how TB IPC measures can contribute to stigma, with some describing feeling ‘less than human’. We found TB IPC measures sometimes exacerbated stigma, for example through introducing physical isolation that became prolonged or through a mask marking the person out as being ill with TB. In this context, stigma emerged from the narrow definition of what mask-wearing symbolises, in contrast with broader uses of masks as a preventative measure. Patient and health workers had contrasting perspectives on the implications of TB IPC-related stigma, with patients focussing on communal benefit, while health workers focussed on the negative impact on the health worker-patient relationship. Participant recommendations to mitigate TB IPC-related stigma included comprehensive information on TB IPC measures, respectful communication between health workers and patients, shifting the focus of TB IPC messages to communal safety (which could draw on ubuntu, a humanist framework) and using universal IPC precautions instead of measures targeted at someone with infectious TB.ConclusionsHealth facilities may unwittingly perpetuate stigma through TB IPC implementation, but they also have the potential to reduce it. Evoking ‘ubuntu’ as an African humanist conceptual framework could provide a novel perspective to guide future TB IPC stigma mitigation interventions, including policy changes to universal IPC precautions.

Online Formative Assessments in Medical Education During COVID-19.

This study aimed to evaluate perception of medical students regarding online mode of assessments and to compare the academic outcomes of various methodologies adopted for online formative assessments. This was a descriptive cross-sectional study. This study was conducted in the department of biochemistry at the constituent medical college of Health University in India and included 150 first year medical undergraduates of either gender. The institutional ethical clearance and written informed consent was taken prior to the study from all the enrolled participants. A series of online formative assessments were designed in the form of multiple choice, short answer questions, case-based learning, and viva-voce to satisfy each learning outcome. Google platform was used for conducting online formative assessment. The participants were asked to fill questionnaire based on 5-point Likert scale to obtain information on challenges and perceptions related to OFA. Academic performance was evaluated and compared for various modes of assessments. The mean age of the participants was 19.34±0.947 years. Most of the students were from urban areas and majority (73.33%) preferred MCQs. 60.67% respondents favored conduction of e-assessments. 80.67% of students agreed that solving clinical cases in the online assessments contributed to clinical learning. Formative online assessment can be used as an intervention to reshape medical education sector during times when infection controls and physical isolation measures are crucial to avoid spread of disease.

Effects of essential caregiver policies on COVID-19 and non-COVID-19 deaths in nursing homes.

Federal authorities banned nursing home visitation in the early days of the coronavirus disease 2019 (COVID-19) pandemic. However, there was growing concern that physical isolation may have unintended harms on nursing home residents. Thus, nursing homes and policymakers faced a tradeoff between minimizing COVID-19 outbreaks and limiting the unintended harms. Between June 2020 and January 2021, 17 states implemented Essential Caregiver policies (ECPs) allowing nursing home visitation by designated family members or friends under controlled circumstances. Using the Nursing Home COVID-19 Public File and other relevant data, we analyze the effects of ECPs on deaths among nursing home residents. We exploit variation in the existence of ECPs across states and over time, finding that these policies effectively reduce both non-COVID-19 and COVID-19 deaths, resulting in a decrease in total deaths. These effects are larger for states that implemented policies mandatorily or without restrictions, indicating a dose-response relationship. These policies reduce non-COVID-19 deaths in facilities with higher quality or staffing levels, while reducing COVID-19 deaths in facilities with lower quality or staffing levels. Our findings support the use and expansion of ECPs to balance resident safety and the need for social interaction and informal care during future pandemics.

Investigating the Unexpected Effect of Bulkheads in a Dementia Model of Mice Through Molecular Analysis of the Hippocampus.

This study aimed to evaluate the impact of long-term exposure to physical barriers used as preventive measures during the coronavirus disease 2019 (COVID-19) pandemic on cognitive function and behavior in an apolipoprotein E-/- (ApoE-/-) mouse dementia model. ApoE-/- mice were divided into co-housed, partitioned by a transparent bulkhead (partitioned), and isolated groups. To assess anxiety, cognitive recognition, and spatial learning, behavioral tests, including the open-field test, novel object recognition test, and Morris water maze test, were conducted at three and six months after the start of the 33-week rearing period. RNA-sequencing analysis of hippocampal tissues was performed to investigate gene expression changes. The partitioned group exhibited reduced exploratory behavior, lower recognition index, and impaired spatial learning compared with the co-housed group. However, the differences were not significant. Based on morphological analysis, the partitioned and isolated groups presented a significant reduction in neuronal density in the hippocampal CA1 region. RNA-sequencing analysis showed significant changes in the expression of genes related to neurotransmitter transport, neurite outgrowth, and neuropeptide signaling pathways. Prolonged physical isolation, even with visual contact, can adversely affect cognitive function and hippocampal structure in dementia models. Changes in gene expression indicate that neurotransmitter imbalances and neuroinflammatory responses may contribute to these effects. These findings emphasize the need to develop new infection-prevention measures for patients with dementia during the COVID-19 pandemic.

Key Synchronization Method Based on Negative Databases and Physical Channel State Characteristics of Wireless Sensor Network.

Due to their inherent openness, wireless sensor networks (WSNs) are vulnerable to eavesdropping attacks. Addressing the issue of secure Internet Key Exchange (IKE) in the absence of reliable third parties like CA/PKI (Certificate Authority/Public Key Infrastructure) in WSNs, a novel key synchronization method named NDPCS-KS is proposed in the paper. Firstly, through an initial negotiation process, both ends of the main channels generate the same initial key seeds using the Channel State Information (CSI). Subsequently, negotiation keys and a negative database (NDB) are synchronously generated at the two ends based on the initial key seeds. Then, in a second-negotiation process, the NDB is employed to filter the negotiation keys to obtain the keys for encryption. NDPCS-KS reduced the risk of information leakage, since the keys are not directly transmitted over the network, and the eavesdroppers cannot acquire the initial key seeds because of the physical isolation of their eavesdropping channels and the main channels. Furthermore, due to the NP-hard problem of reversing the NDB, even if an attacker obtains the NDB, deducing the initial key seeds is computationally infeasible. Therefore, it becomes exceedingly difficult for attackers to generate legitimate encryption keys without the NDB or initial key seeds. Moreover, a lightweight anti-replay and identity verification mechanism is designed to deal with replay attacks or forgery attacks. Experimental results show that NDPCS-KS has less time overhead and stronger randomness in key generation compared with other methods, and it can effectively counter replay, forgery, and tampering attacks.

Supporting students’ wellbeing through a virtual resilience application during COVID-19 pandemic

The coronavirus disease of 2019 (COVID-19) impacted learning experiences of students around the world. To limit the spread of the infectious virus, public health officials had to implement various measures that included lockdowns and physical isolation. Such measures also impacted students’ access to support systems and negatively impacted their overall wellbeing. Through this project, students at a community college were offered access to a virtual resilience training through the Headversity application. The Headversity application provides training in six skills namely, mental health, mindfulness, self-expertise, energy management, hardness and mental fitness. Students completed a pre and post survey designed to gather their experiences. The Headversity service provider shared the performance indicators every 3 months. The performance indicators showed the skills that was accessed more frequently and the skills that needed more attention. A total of 346 students enrolled to use the application. Of these, 163 enrolled to complete the survey. It was evident from students’ feedback that the virtual application was easy to navigate, helped them to train on relevant skills and was timely given the COVID-19 pandemic. However, a few students indicated that they would have preferred contact with a trainer rather than getting generic support system through the application.

Dual-species proteomics and targeted intervention of animal-pathogen interactions

IntroductionHost-microbe interactions are important to human health and ecosystems globally, so elucidating the complex host-microbe interactions and associated protein expressions drives the need to develop sensitive and accurate biochemical techniques. Current proteomics techniques reveal information from the point of view of either the host or microbe, but do not provide data on the corresponding partner. Moreover, it remains challenging to simultaneously study host-microbe proteomes that reflect the direct competition between host and microbe. This raises the need to develop a dual-species proteomics method for host-microbe interactions. ObjectivesWe aim to establish a forward + reverse Stable Isotope Labeling with Amino acids in Cell culture (SILAC) proteomics approach to simultaneously label and quantify newly-expressed proteins of host and microbe without physical isolation, for investigating mechanisms in direct host-microbe interactions. MethodsUsing Caenorhabditis elegans-Pseudomonas aeruginosa infection model as proof-of-concept, we employed SILAC proteomics and molecular pathway analysis to characterize the differentially-expressed microbial and host proteins. We then used molecular docking and chemical characterization to identify chemical inhibitors that intercept host-microbe interactions and eliminate microbial infection. ResultsBased on our proteomics results, we studied the iron competition between pathogen iron scavenger and host iron uptake protein, where P. aeruginosa upregulated pyoverdine synthesis protein (PvdA) (fold-change of 5.2313) and secreted pyoverdine, and C. elegans expressed ferritin (FTN-2) (fold-change of 3.4057). Targeted intervention of iron competition was achieved using Galangin, a ginger-derived phytochemical that inhibited pyoverdine production and biofilm formation in P. aeruginosa. The Galangin-ciprofloxacin combinatorial therapy could eliminate P. aeruginosa biofilms in a fish wound infection model, and enabled animal survival. ConclusionOur work provides a novel SILAC-based proteomics method that can simultaneously evaluate host and microbe proteomes, with future applications in higher host organisms and other microbial species. It also provides insights into the mechanisms dictating host-microbe interactions, offering novel strategies for anti-infective therapy.

Assessment of Web Security Vulnerabilities for Common Open Source Virtualization Software

Open-source hypervisors have emerged as an integral technology for virtualizing server resources in cloud and data center computing. Hypervisor security efficiency is determined by virtual machine isolation, which is a de facto adoption factor in the selection process, as well as its ability to respond to web attacks. This paper assesses the security performance of Proxmox VE and XenServer for type 1 hypervisors, and Kernel Virtual Machine and Oracle Virtual Box for type 2 hypervisors. Security analysis was conducted using common exposures extracted from vulnerability databases and mapped against the OWASP 2013 and 2017 projects. For clarity, experiments were carried out on a testbed with prebuilt virtual machines, each hosting one hypervisor installed as an attack target. Kali Linux was configured in one virtual machine to run recursive penetration testing for information gathering, vulnerability detection, penetration attempts, and exploitation of weak spots. The infrastructure was set in both homogeneous and heterogeneous execution environments, with a series of tests nested with each other. All four hypervisors are vulnerable to physical kernel isolation, as unprivileged users can gain root access and launch guest-to-guest and host-to-guest attacks. Among the two, guest-to-guest attacks were found to be more common than host-to-guest attacks, indicating that virtual machine isolation is weaker than the underlying host. Type 1 hypervisors have a lower rate of host-to-guest attacks than guest to-guest attacks, implying that XenServer and Proxmox VE provide better isolation than KVM and OVB due to the near-native speed, security, and efficiency of their virtual machines. All four hypervisors were found to be vulnerable to buffer overflow exploits and error-triggering sensitive information leaks, which were primarily caused by adopter default misconfigurations in the deployment process rather than software design flaws. This implies that greater efforts are required by open-source adopters when shifting from physical to virtual computing.

Stable Interlayer Zinc Plating/Stripping in the Maxwell-Wagner Effect-Enhanced Interface.

Zinc metal batteries have recently emerged as a promising stable and reversible anode aqueous battery. However, due to the serious dendrite problem and hydrogen evolution problem of the zinc metal anode, the practical application of the zinc metal battery is limited. Here, we propose Y2O3 as an effective coating, which inhibits hydrogen evolution and side reactions by physical isolation and simultaneously prevents dendrite growth by ensuring a uniform Zn-ion flux and fast transport channels generated by Maxwell-Wagner polarization, thus improving the stability of batteries. Meanwhile, in situ/ex situ characterizations and different simulations are conducted to investigate in detail the effect of Maxwell-Wagner polarization on the performance of Zn metal batteries. The symmetric Y2O3@Zn anode system exhibits a stable electroplating/stripping performance over 780 h and enables the Zn battery to achieve a Coulombic efficiency of up to 99.81% over 1000 cycles by reducing side reactions. The Y2O3@Zn||MnO2 full cell delivers a high energy density of 301.42 Wh kg-1 at a power density of 205.04 W kg-1. The work provides insights into the reversibility and stability of zinc anodes and provides a promising way to promote the practical application of Zn metal batteries.

Across a phylogeographic break in the Qinling Mountains-Huaihe River Line: Quaternary evolutionary history of a medicinal and edible homologous plant (Allium macrostemon) in China

Biogeographic barriers to gene flow are central to studies of plant phylogeography. There are many physical and geographic barriers in China, but few studies have used molecular ecological evidence to investigate the natural geographic isolation barrier of the Qinling Mountains-Huaihe River Line (QHL). Allium macrostemon is a precious Chinese perennial herb belonging to the Amaryllidaceae family. It is used as a food and medicine, with a variety of health and healing properties. Five SSR markers, three chloroplast DNA (cpDNA) markers (psbA-trnH, rps16 and trnL-F), one nuclear ribosomal DNA (nrDNA) marker (ITS), and simplified genome GBS sequencing were used to analyse the genetic diversity and structure of A. macrostemon. Combining SSR, cpDNA, nrDNA ITS data and GBS analysis results, we divided A. macrostemon populations into northern and southern groups, with the southern group further divided into southwestern and central-southeastern groups. Niche simulation results reveal that the distribution area of A. macrostemon will reach its maximum in the future. These data indicate that the regional separation of A. macrostemon has been maintained by the combined influence of a geographical barrier and Quaternary climate, and that the back-and-forth fluctuations of QHL and Quaternary climate have played an important role in this process. QHL acts as a north-south dividing line in phylogeography and population genetic structure, promoting physical geographic isolation. This study provides a theoretical basis for the conservation, development, and utilization of A. macrostemon resources. It further provides a reference for understanding the systematic geographical pattern of the large-scale spatial distribution of plants in China and enriches our understanding of Quaternary plant evolution in areas with complex terrain.

HydraulicBridge: Covert Signaling Channel between Air-Gapped Systems Using Hydraulic-Pressure Fluctuations

To protect critical computing systems from network attacks, modern enterprises typically employ physical isolation measures to disconnect them from open networks such as the Internet. However, attackers can still infiltrate these closed networks through internal employees or supply chain vulnerabilities. This presents the primary challenge that attackers face: how to effectively manage and manipulate infected devices that are isolated from the external network. In this paper, we propose a new covert communication technology called HydraulicBridge, which demonstrates how air gap networks can communicate through covert water pressure-fluctuation channels. Specifically, we demonstrate how water pressure from water pipes can be used to communicate with infected hosts within an air gap network. Additionally, we provide experimental results demonstrating the feasibility of covert channels and test the communication speed in the experimental environment. Finally, we offer a forensic analysis and propose various methods for detecting and blocking this channel. We believe that this study provides a comprehensive introduction to previously unseen attack vectors that security experts should be aware of.