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Gukov–Pei–Putrov–Vafa conjectured the existence of q-series whose radial limits are Witten–Reshetikhin–Turaev invariants and called them homological blocks. For weakly negative definite plumbed 3-manifolds, Gukov–Pei–Putrov–Vafa and Gukov–Manolescu constructed homological blocks. In this paper, we construct indefinite false theta functions which are candidates of homological blocks for some plumbed 3-manifolds which are not weakly negative definite. Moreover we prove that, for the Poincaré homology sphere, our indefinite false theta function coincides with the original homological block. [ABSTRACT FROM AUTHOR]

We performed chlorine inactivation experiments for Elizabethkingia anophelis and E. meningoseptica bacterial strains from clinical and environmental sources. Free chlorine concentration × contact time values <0.04 mg·min/L achieved 99.9% inactivation of Elizabethkingia species, indicating chlorine susceptibility. Measures to control biofilm producing pathogens in plumbing are needed to prevent Elizabethkingia bacterial infections. [ABSTRACT FROM AUTHOR]

Indoor construction environments, with their high density and detailed components, are complex areas for progress monitoring and reporting. Traditional manual monitoring systems, often constrained by poor lighting and accessibility, are inaccurate and time-consuming. With recent technological advancements, deep learning-based object recognition models have achieved considerable attention in construction. This paper introduces a novel method for progress monitoring and reporting of construction operations, employing digital imaging and the You Only Look At CoefficienTs (YOLACT++) deep learning algorithm to automatically recognize mechanical, electrical, and plumbing (MEP) components in challenging indoor settings. Data augmentation techniques and transfer learning were applied to improve the model's generalization and adaptability. The study distinctively focuses on complex components in complicated indoor environments, a less explored area in current research that mainly centered on outdoor or simpler indoor settings. To achieve this, the study enhanced the dataset quality by generating synthetic images that closely represent actual indoor conditions including different lighting, object complexity and scale, occlusion, clutter, and viewpoints. This study also evaluated different mixes of synthetic and real images to determine the optimum combination for effective training. Moving beyond commonly used algorithms such as Mask R-CNN and You Only Look Once (YOLO), the method applied in this work is the YOLACT++ with deformable convolutional neural networks v2 (DCNv2), enhancing the model's ability to handle objects with different scales, postures, rotations, and viewpoints in the images that are essential in indoor environments. The model is validated on a large test dataset, including real images from construction sites, to cover different indoor scenarios. The model achieved a precision of 84.80% and a recall of 85.58% for HVAC duct detection and a precision of 86.87% and a recall of 73.93% for pipe detection, demonstrating its effectiveness under challenging conditions. This method contributes to more accurate automated progress monitoring in indoor environments by reducing manual and error prone inspections. [ABSTRACT FROM AUTHOR]

Lead (Pb) in drinking water is a serious concern due to its adverse health impacts. Aiming to identify sources and contributing factors of waterborne Pb, this study tracked Pb at different locations in Addis Ababa's (capital of Ethiopia) water distribution system, successively from 3 water sources, 15 storage reservoirs and 88 taps. The mean Pb concentration at sources was 2.6 µg/L, significantly varying from the concentration at taps, 15.9 µg/L (ANOVA Post Hoc, P = 0.02). A significant variation of Pb was also observed among the city's water distribution sub-systems and source waters (ANOVA Post Hoc, P = 0.006). Surface waters exhibited a negative Langelier saturation index (LSI) and higher corrosivity. Analysis from first-drop and flushed water samples showed that water stagnation for 6–8 hours would increase Pb leaching by 11.5 Points (95% CI [6.23, 16.78]). Metal plumbing releases more Pb compared to plastics (t30 = −4.358, P < 0.001), where the leaching is higher from new faucets than the old (r = −0.368, P < 0.05). A multiple linear regression (R2 = 0.61, F5, 80 = 24.617, P < 0.001) predicted that a 1% increase of Fe in the water can raise the Pb concentration by 0.35% (t80 = 7.033, P < 0.001), while 1% increment of Zn can raise Pb by 0.21% (t80 = 4.45, P < 0.001). The analysis suggests that leaded-brass and galvanised-steel could be important Pb sources. In conclusion, Pb contamination in Addis Ababa's drinking water system chiefly arises from the plumbing and pipelines, where the main portal of entry lies between storage reservoirs and taps. Water properties (hardness, tendency to scale formation and corrosivity), water stagnation time in pipelines, and material types and age of premise plumbing were significant contributing factors. [ABSTRACT FROM AUTHOR]

Disasters can prompt hydrocarbon contaminants to reach building water systems, and ultimately customer fixtures. Here, seven water supply connectors (e.g., ice‐maker lines, faucet connectors, washing machine hoses) were exposed to contaminated water, and were subsequently decontaminated by water flushing. After a 24 h contamination period, water samples were collected after three consecutive 72 h exposure periods. Samples were characterized for volatile organic compound, semi‐volatile organic compound, and total organic carbon concentrations. New, uncontaminated, PVC tubing leached phenol at concentrations that exceeded the health advisory. All materials sorbed more than 90% of hydrocarbon contaminants during the initial exposure period. All materials then released the contaminants into the water during decontamination, at times above health‐based limits. The majority of sorbed mass remained in the plastics at the end of the decontamination effort, indicating the products posed continued leaching risks. Public health guidance considerations and research needs were identified. [ABSTRACT FROM AUTHOR]

The surface gap of tephriphonolite compositions in the Passa Quatro alkaline complex, in SE Brazil, is attributed to non-buoyancy of these high viscosity intermediate compositions during magmatic fractional crystallization at different depths. Thermodynamic and Rayleigh models for three alkaline suites of a strongly silica-undersaturated series were integrated to demonstrate that parental (basanite, nephelinite and alkaline basalt) and residual (phonolites) magmas are cogenetic by fractional crystallization at pressures of 10 kbar and 5 kbar, i.e. at magma chambers located above and below the Conrad discontinuity within the Upper Cretaceous-Palaeogene 40 km-thick continental crust in SE Brazil. The fractional crystallization of the parental magmas produced an ultramafic residual solid (wehrlite, olivine-bearing clinopyroxenite and clinopyroxenite) and residual liquids (evolved basanite and alkaline basalt, and phonotephrite). The latter moved up and built magma chambers at lower depths in the continental crust where those magmas initially crystallized clinopyroxenite extracts and high viscosity residual liquid that was entrapped and prevented to ascent towards the surface. Then, an abrupt change in the extract mineralogy produced a feldspathic-rich extract (leucocratic leucite monzosyenite, mesocratic syenite or leucocratic monzodiorite) and a residual phonolitic liquid with low viscosity. Following the feldspar crystallization, the magma viscosity decreased, acquiring adequate buoyancy that resulted in shallow-crust magma chambers in which phonolite diversification took place. These processes occurred due to the existence of a transcrustal, plumbing architecture where the high viscosity intermediate tephriphonolites were prevented to reach shallower depths, resulting in the Daly gap observed in the Passa Quatro Alkaline Complex. [ABSTRACT FROM AUTHOR]

For active volcanoes, knowledge of the architecture of the plumbing system and the conditions of magma storage prior to an eruption are highly important, given their influence on the eruptive style and, thus, the management of future volcanic crises. Here, chlorine is used as a geobarometer for potassic alkaline magmas at the Campi Flegrei volcanic complex, revealing the shallowest depth of fluid-melt equilibration with respect to Cl. The results for representative fallout deposits of selected explosive eruptions show the existence of a multi-depth equilibration zone through time, including shallow magma storage. We describe evidence for the shallowest zone located at a depth equivalent to 65 MPa for the Agnano Monte Spina eruption (4482–4625 cal. yrs BP), at ~100 MPa for the Pomici Principali (11 915–12 158 cal. yrs BP), and the Astroni 6 (4098–4297 cal. yrs BP) eruptions, and close to 115 MPa for the last explosive eruption of Monte Nuovo (AD 1538). For comparison, the pressure estimated for a possible reservoir feeding the Cretaio eruption of Ischia island (AD 430), the only studied eruption on Ischia, is ~140 MPa. The pressure estimates for the two largest magnitude eruptions, the Campanian Ignimbrite (40 ka) and the Neapolitan Yellow Tuff (14.9 ka), are also discussed with respect to available magma withdrawal models. The pressures estimated using the Cl geobarometer for the magma leading to the fallout phases of these two eruptions provide evidence for a low-volume, shallow domain (~40 MPa) for the Plinian phase of the Campanian Ignimbrite eruption and a main, deeper reservoir (~130–165 MPa) for the Neapolitan Yellow Tuff eruption. The inferred shallowest equilibration pressures are interpreted here as corresponding to transitory, short-lived magma apophyses, whose eruption may have been facilitated by optimum tectonic stresses, rheological behavior of the crust, and efficiency of volatile exsolution. Alternatively, these magma apophyses may represent an evolved, crystal-rich ponded magma into which a volatile-rich magma ascending from depth was injected. The transient nature of such very shallow reservoirs is suggested by the short timescales inferred from diffusion modeling on crystals available in the literature for the studied Campi Flegrei eruptions. The influence of sulfur (S) on Cl solubility is assessed through Cl solubility modeling and applied to different eruptions. In addition, the pressure at which magmatic fluids and melts equilibrated with respect to Cl is shallower for the Campi Flegrei volcanic complex than the Somma-Vesuvio volcanic complex, erupting more homogeneous differentiated magma, of trachytic or phonolitic composition. This approach of using Cl to investigate the architecture of the plumbing system can be extended to all alkali-rich magma systems. [ABSTRACT FROM AUTHOR]

Increasing regulatory and market changes that decouple fossil fuels from the built environment will require existing trade practitioners to upskill. However, the structure of the construction sector, which includes short-term contracts, tight deadlines, high reliance on contingent labor, and a large proportion of small-business contractors who are responsible for their own training makes upskilling challenging. Consideration of the industry's structure and the characteristics of small trade business learning practices is necessary for any upskilling program. Plumbing is a key example of a trade requiring upskilling for a low-carbon economy. The gas fitting component of plumbing work will change dramatically with the phasing out of carbon-producing natural gas and substitution with alternatives such as hydrogen. This study used a survey of 1,001 Australian plumbers, informed by the theory of planned behavior (TPB), to understand the learning contexts and needs of plumbers in upskilling and ascertain attitudinal, social, and structural enablers for training behavior. The results show that attitudes to training, including the perceived benefits of training for skills development and end-user safety, are the key motivator for plumbers' training behavior, whereas social norms and behavioral controls such as time and cost are somewhat influential. The findings provide insight into training behavior enablers that can be leveraged to support the roll-out of upskilling for low-carbon technologies and ongoing trades training programs more broadly. [ABSTRACT FROM AUTHOR]

A global transition to low-carbon, resource-efficient economies is occurring in response to risks posed by climate change and environmental degradation. Hydrogen is proposed as a zero-carbon substitute for natural gas with the potential to reduce carbon emissions in homes and businesses. Trades, including gasfitting, will be affected by the transition to a low-carbon economy and require upskilling to develop competencies to work with hydrogen to ensure safety and support domestic uptake. Understanding the training needs of trades practitioners is essential to the successful transition to a zero-carbon economy. This paper presents findings from a qualitative study of Australian gasfitters, exploring what motivates gasfitters to participate in training, what informs their ongoing learning and what their preferences are for hydrogen training. Most gasfitters are either self-employed or work in small businesses, and, as such, this context presents both challenges and opportunities to consider in upskilling strategies. Drawing on interview findings and literature on small business learning, the paper presents considerations to inform training approaches and policies in the transition to hydrogen and also, more broadly, for upskilling other small trade businesses similarly affected by a shift to low-carbon and green technologies. [ABSTRACT FROM AUTHOR]

Lamprophyres are spatially and temporally widespread in continental belts, but their magmatic differentiation process and melting dynamic mechanisms remain subjects of debate. In this study, we report mineral chemistry, bulk-rock compositions, and Sr-Nd-O isotopes of the alkaline lamprophyres (including monchiquite and camptonite) from the Tuoyun Basin of the southwestern Central Asian Orogenic Belt. Based on the P-T estimates, transcrustal magmatic reservoirs from the lower crust to upper crust are revealed for monchiquite and camptonite. These magmatic reservoirs were potentially connected, and the magmatic recharge and mixing processes that occurred were recorded by zoned clinopyroxene and amphibole. The diverse crystal populations are suggested to have originated from multiple batches of magmas, which were then involved in forming the subsequent magmas. The Sr-Nd isotopic compositions are relatively depleted, with (87Sr/86Sr)i = 0.70390-0.70452 and εNd(t) = 5.46-6.49 for the monchiquite, while the values for camptonite are 0.70391-0.70463 and 4.71-5.02. Moreover, the olivine in situ O isotopes in the monchiquite show Î'18OV-SMOW values of 4.81‰-5.40‰, which are comparable to those of the mantle peridotite. Compared with the experimental melts, a hybridized mantle source of hydrous peridotite + silica-depleted pyroxenite is proposed, and partial melting of this component was induced by the upwelling asthenosphere. Ultimately, our study highlights the critical role of the magmatic plumbing system and hydrous mantle source in the formation of Tuoyun lamprophyres. [ABSTRACT FROM AUTHOR]

The Pleiades Volcanic Field (PVF) of northern Victoria Land (Antarctica) is made up of a dozen scoria cones whose erupted products present an unusually complete evolutionary trend from alkali-basalt to trachyte. With the aim of reconstructing the evolution of the PVF plumbing system, we have investigated the petrography and chemistry of main mineral phases using scanning electron microscopy (SEM-EDS) coupled with major element analyses using an electron probe microanalyser (EPMA-WDS). We further focussed on clinopyroxene phenocrysts obtaining a more detailed characterization by means of trace laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) element analyses coupled with machine learning thermobarometry. The results indicate that fractional crystallization and magma mixing are the major processes determining the development of the complete evolution trend. While fractional crystallization is a persistently active process in all parts of the plumbing system, mixing among differently evolved magma batches pertaining to the same association is responsible for the formation of intermediate compositions in the differentiation lineage at a specific pressure range (0.4–0.5 GPa). These processes are compatible with significant residence time of magmas at depth, resulting in multiple episodes of magma mixing, as testified by resorption and overgrowth textures in phenocryst assemblage occurring under isobaric conditions. The prolonged residence time likely increased the efficiency of the mixing process, leading to the formation of magmas with intermediate composition. In turn, the build-up of volatiles during the magma differentiation at depth could have favoured the eruption of these (variably differentiated) magmas. Considering that the PVF is situated in a glacial region, a process forcing long magma residence time can be envisaged associated with increased ice loading during glacial stages. This study specifically considers the ice fluctuations in the last 100 ka, theorizing the possibility of a climate-controlled volcano plumbing system. [ABSTRACT FROM AUTHOR]

Volcanoes produce a variety of seismic signals and, therefore, continuous seismograms provide crucial information for monitoring the state of a volcano. According to their source mechanism and signal properties, seismo‐volcanic signals can be categorized into distinct classes, which works particularly well for short transients. Applying classification approaches to long‐duration continuous signals containing volcanic tremors, characterized by varying signal characteristics, proves challenging due to the complex nature of these signals. That makes it difficult to attribute them to a single volcanic process and questions the feasibility of classification. In the present study, we consider the whole seismic time series as valuable information about the plumbing system (the combination of plumbing structure and activity distribution). The considered data are year‐long seismograms recorded at individual stations near the Klyuchevskoy Volcanic Group (Kamchatka, Russia). With a scattering network and a Uniform Manifold Approximation and Projection (UMAP), we transform the continuous data into a two‐dimensional representation (a seismogram atlas), which helps us to identify sudden and continuous changes in the signal properties. We observe an ever‐changing seismic wavefield that we relate to a continuously evolving plumbing system. Through additional data, we can relate signal variations to various state changes of the volcano including transitions from deep to shallow activity, deep reactivation, weak signals during quiet times, and eruptive activity. The atlases serve as a visual tool for analyzing extensive seismic time series, allowing us to associate specific atlas areas, indicative of similar signal characteristics, with distinct volcanic activities and variations in the volcanic plumbing system. Plain Language Summary: Volcanoes generate diverse seismic signals, and analyzing continuous seismograms can offer valuable insights into a volcano's behavior. However, classifying and cataloging these signals is challenging, particularly for long‐period signals such as volcanic tremors with varying signal characteristics. In this study, we utilize seismic time series data from the Klyuchevskoy Volcanic Group in Russia, employing machine learning and signal processing methods to transform and represent the time series data. The resulting "seismogram atlas" helps identify changes in signal properties, revealing a dynamic seismic wavefield linked to the evolving plumbing system of the volcano. This approach provides a comprehensive understanding of the volcanic behavior in time by connecting signal variations to different volcanic states, such as shifts in activity depth, reactivation, and eruptive periods. These findings highlight the unique characteristics of continuous seismograms near the volcano, suggesting that there is valuable information in the complete seismic time series that conventional methods and event catalogs may miss. Key Points: With machine learning, we analyze 1 year long seismic time series at individual stations at Klyuchevskoy volcanoContinuous evolution of the signal characteristics over time reflects dynamic changes occurring in the volcano plumbing systemDifferent episodes of volcanic activity are well distinguished on UMAP‐based seismogram atlases [ABSTRACT FROM AUTHOR]

The application of whole-rock compositions to trace magma evolution or crystal-melt equilibrium may be called into question when foreign crystals are incorporated into host magmas. To address this challenge, establishing the origins (orthocrysts, antecrysts, xenocrysts, etc.) of minerals with variable textures in magmatic plumbing systems is necessary. In this paper, we describe complex oscillatory zoning patterns of clinopyroxenes (Cpx) from the Miocene Majuangou (MJG) alkali basalts from West Qinling, China. Our detailed petrographic, mineralogical, and geochemical analyses unravel the origins of various Cpx crystals with distinct textural patterns, thereby providing information about magma storage, recharging and/or mixing, and transportation, as well as the reactions between crystals and melts/fluids. Based on textural patterns, Cpx may be divided into four types: normal (Type-1 Cpx), simple oscillatory (Type-2 Cpx), complex oscillatory (Type-3 Cpx), and grains that lack zoning (Type-4 Cpx, suggested to be orthocrysts). Through the textural characterization of Cpx, the comparison between different types of Cpx, and the relationships between Cpx major compositions from different lithologies, we concluded that Type-1–3 Cpx cores are antecrysts or xenocrysts with diverse origins: primitive magma (Type-1 Cpx cores), magma mush (Type-2 Cpx cores), and crustal granulite (Type-3 Cpx cores). The zoning patterns and the compositions of these Cpx crystals indicate at least three batches of magmatic activity, i.e., the Batch-1 low-Mg# magma (Mg#: 47.4–53.3), the Batch-2 primitive magma (Mg#: 57.2–64.5), and the Batch-3 low-Mg# host alkali magma (Mg#: 47.2–54.6). Cpx-melt thermobarometry demonstrates that at least two crustal magma reservoirs existed in the magma plumbing system at depths of 30.1 and 40.9 km. The antecrystic/xenocrystic Cpx cores were captured by, continued to grow in, and subsequently reacted with ascending K-rich melt/fluid. The spongy textures in Cpx cores/mantles are attributed to this reaction, which may be expressed as: Melt 1 (primitive or evolved) + K-rich melts/fluids + Cpx (CaMgSi2O6) = K-feldspar (KAlSi3O8) + ilmenite (FeTiO3) + Melt 2 (derivative). The products of this reaction (K-feldspar and ilmenite) filled the sieves in the spongy zones of Type-1–3 Cpx. This detailed investigation of compositional and textural features of Cpx antecrysts/xenocrysts suggests that the interactions between various interconnected magma reservoirs are widespread beneath the magmatic plumbing system. Our study emphasizes the importance of the incorporation of foreign crystals and the Cpx-melt/fluid reaction in magmatic plumbing system, which can significantly modify the whole-rock compositions and lead to the formation of spongy textures without the need for fractures and cracks in minerals. [ABSTRACT FROM AUTHOR]

Disasters such as the Ahr Valley flood in 2021 make us aware of the importance of functioning healthcare facilities. Their functionality depends on the availability of drinking water. Water safety planning is a long-established method to increase the safety of water utilities. Our work supports the implementation of water safety planning in healthcare facilities during normal operations and emergency situations concerning the water supply. The authors conducted a stakeholder mapping exercise and problem awareness analysis. Based on these results, it was identified what is needed to overcome barriers to water safety planning (WSP). Building on existing procedures, the WSP concept, and latest scientific findings, an event-specific risk assessment method for healthcare facilities was developed and applied in a case study. Based on an analysis of water demand, water-related processes, and infrastructure, potentially necessary components for establishing an emergency supply were identified. For these, based on technical and legal requirements, planning principles were developed, and prototypes of components for emergency water supply were built. They were tested in pilot trials, particularly regarding hygienic safety. For the management of crises in hospitals, a survey was carried out on the command structures used in practice. Finally, recommendations were drawn based on the German Hospital Incident Command System. [ABSTRACT FROM AUTHOR]

The Nyiragongo volcano is one of the most alkali-rich volcanic centres on the planet (Na2O + K2O generally >10 wt.%, agpaitic index up to 1.34), characterized by a semi-permanently active lava lake which hosts silica-undersaturated (SiO2 < 40 wt.%), low viscosity lavas. To improve our understanding of this unique magmatic system, we present a set of 291 samples, acquired during new field excursions between 2017 and 2021. The major and trace element composition of all samples was measured, revealing a lithological range extending from primitive picrites (Mg# 82) erupted from parasitic cones to a variety of highly evolved nephelinites, leucitites, and melilitites erupted from the main edifice as recently as 2002, 2016, and 2021. We measured major and trace element compositions from the full spectrum of minerals present in all sampled lithologies. From these we calculated that the main magma reservoirs feeding Nyiragongo are at approximately 9–15 and 21–33 km depth, in agreement with recent seismic observations. Fractional crystallization modelling using observed mineral compositions and proportions was performed to quantitatively link the lithologies to specific residual liquid fractions assuming evolution from an olivine-melilite parental melt. Our modelling indicates that fractionation and cumulate formation in deep chambers reduces the remaining melt fraction to ~60%, after which melts are injected into upper, liquid dominated magma chambers where fractionation and accumulation of clinopyroxene, melilite, and feldspathoids dominates. Characterisation of mineral textures and geochemistry reveals high crystal mobility in a repeatedly recharging plumbing system split between liquid-dominated, evolved magma chambers and more solid-dominated, primitive mushes, decreasing in liquid fraction with depth. [ABSTRACT FROM AUTHOR]

Starting from a resilience assessment of Harare's water supply, the system interactions of the city's water management arrangements are explored through a series of causal loop diagrams. These are based on economic, physical, commercial, environmental, and social subsystems and the reinforcing and balancing loops that influence key variables of interest in each are identified. The analysis identifies a series of shortcomings including a weak provider-customer relationship, limited governance capacity, inadequate coordination and integration between key players, shortfalls in physical supply and critical infrastructure, environmental degradation, and a lack of disaster response and recovery measures. A series of strategies are proposed as intervention actions that target the areas of potential leverage identified in the causal loop analysis, including improving customer-provider relationships; increasing coordination, collaboration, and integration; developing physical and informational infrastructure and enhancing environmental protection and rehabilitation. The impacts of these strategies are highlighted as strengthening key elements of the causal loop diagrams and addressing the resilience gaps identified. The systems mapping approach reveals that key issues are large-scale, cross-sectoral, and compounding. Remediation strategies must therefore also be multi-faceted and holistic in scope. [ABSTRACT FROM AUTHOR]

Geophysical data provide the chance to investigate a volcano's dynamics; considerable information can especially be gleaned on the stress and strain patterns accompanying the internal processes and the effect of magma ascent on the main structures triggering earthquakes. Here, we analysed in detail the seismicity recorded over the last two decades on Etna volcano (southern Italy), focusing on earthquakes distribution and focal mechanism clustering; the ground deformation pattern affecting the volcanic edifice with the inflation and deflation phases was also examined. Analysed data were compared in order to shed light on possible relationships with the volcanic activity and to better understand the internal dynamics of the volcano over time. Significant steps during or shortly before major eruptions in the seismic strain release and ground deformation temporal series highlight a straightforward relationship between seismicity occurring at shallow level, inflation/deflation and volcanism. Furthermore, at depths greater than 5–7 km, down to about 20 km, the orientation of the P- and T-axes clearly indicate the existence of a pressure source in the central part of the volcano. All the results underline that the stress field related to the volcano plumbing system interferes with the regional field, partly overriding it. [ABSTRACT FROM AUTHOR]

Some recent studies have used actual water end-use data to inform the peak demand design of plumbing systems in residential buildings, addressing the problem of overestimation in many long-standing plumbing codes and standards. Vast amounts of fixture-specific data from each household are required to determine the frequency each fixture is used during peak water consumption periods (fixture-use probability). However, obtaining such data can be difficult, and the processing is costly and time-consuming. The current study presents a new approach for determining the fixture-use probability for peak water demand design of premise plumbing systems. A stochastic water demand model is developed using only the high-level statistical information from water end-use studies presented in the public domain, offsetting the need for the original water end-use data sets. The stochastic model is then used to form easy-to-use formulas for determining the probability of use for various fixture groups, which consider both the number of apartments and building occupancy. The approach is validated by comparing the estimated peak demand values with the corresponding values determined from actual water consumption observations in three Australian residential apartment buildings and one mixed-use building. The new approach enables a much more accurate estimation of the peak demand compared with the conventional approach suggested in the current Australian plumbing standard. The proposed approach can be used by researchers and practitioners in other countries to determine their region-specific fixture-use probability values for more accurate peak demand estimation, contributing to improved premise plumbing system design. [ABSTRACT FROM AUTHOR]

Per- and polyfluoroalkyl substances (PFAS) from aqueous film forming foam (AFFF) can be accidentally backflushed into drinking water systems during firefighting operations or at industrial facilities. If this contaminated water enters household plumbing systems, homeowners may need to decontaminate their plumbing. This study examines the persistence of PFAS from AFFF on home plumbing, along with the effects of flushing and stagnation. Two sources of AFFF were investigated, representing older formulations (that contain longer chain PFAS) and newer formulations (that contain shorter chain PFAS). Experiments were conducted in copper, polyvinyl chloride (PVC), and cross-linked polyethylene (PEX) pipes with flushing after contamination followed by intermittent flow and periods of stagnation meant to mimic typical household use. Flushing immediately reduced the PFAS concentration in water leaving the pipe by 99.95% to 99.99%. However, PFAS concentration increased after periods of stagnation, corresponding to slow release of adhered PFAS. Flushing may be a valuable part of the decontamination process, but flushing parameters and duration need to be optimized for local conditions. [ABSTRACT FROM AUTHOR]

Geophysical data provide the chance to investigate a volcano's dynamics; considerable information can especially be gleaned on the stress and strain patterns accompanying the internal processes and the effect of magma ascent on the main structures triggering earthquakes. Here, we analysed in detail the seismicity recorded over the last two decades on Etna volcano (southern Italy), focusing on earthquakes distribution and focal mechanism clustering; the ground deformation pattern affecting the volcanic edifice with the inflation and deflation phases was also examined. Analysed data were compared in order to shed light on possible relationships with the volcanic activity and to better understand the internal dynamics of the volcano over time. Significant steps during or shortly before major eruptions in the seismic strain release and ground deformation temporal series highlight a straightforward relationship between seismicity occurring at shallow level, inflation/deflation and volcanism. Furthermore, at depths greater than 5–7 km, down to about 20 km, the orientation of the P- and T-axes clearly indicate the existence of a pressure source in the central part of the volcano. All the results underline that the stress field related to the volcano plumbing system interferes with the regional field, partly overriding it. [ABSTRACT FROM AUTHOR]

Water quality degrades with time as water travels to users through pipes. Water age (as a surrogate quality indicator) is not limited to distribution networks but carries through the residential premise plumbing system to the tap. Poorly designed premise plumbing layouts and intermittent usage patterns can lead to high residence times. This work aims to numerically quantify water age in residential premise plumbing systems using a stochastic demand simulator and a hydraulic solver. Plumbing layouts based on real houses are assessed and modified to determine design practices that lower water age. Results suggest that best practices are to loop the plumbing system or connect water closets at the end of the premise distribution branches to ensure periodic flushing. However, none of these approaches impacts the "last foot" of pipe connecting plumbing fixtures with the premise distribution pipes. The effect of fixture use intensity and water heater types on residence times is also assessed. The introduction of more efficient fixtures with their lower flows over the last several decades has increased residence times. On-demand heaters reduce water ages across all layouts at the outlet and the point of connection of the fixture. Autoflushers, installed in the hot water system, further decrease water age. [ABSTRACT FROM AUTHOR]

The study of individual volcanoes in northwest Java has been largely overlooked. In this study, an investigation of the magma evolution and plumbing system of Gede-Salak Volcano was conducted. A geological survey determined the lava unit and volcanism. The whole-rock geochemistry is utilized to determine the magma type and evolution. Mineral chemistry based on microprobe analysis revealed the magmatic process and phenocryst origin. Geothermobarometry is employed to estimate the temperature and pressure. The volcanism comprised the eruption of lava flows, sector collapse, and the eruption of lava domes. The magma evolution consists of two magma types: type A (lava flow and peripheral dome) and type B (summit dome). The processes identified are amphibole fractionation, magma mixing, and crust assimilation. Phenocryst textures and chemistry implied open-system processes in the plumbing system involving three magma series, namely the felsic, intermediate, and mafic series. Magma type A resulted from multiple mafic recharges on the felsic series, while type B resulted from the mixing of intermediate and mafic series. The felsic and intermediate phenocryst crystallization occurred at 933-948°C and 1010-1011°C in the mid-crust at 14 km to 17 km depth. Meanwhile, the mafic series reside in the lower crust at 21 km depth and of 1065-1087°C temperature. [ABSTRACT FROM AUTHOR]

Background: Accumulating evidence shows a role of the hospital wastewater system in the spread of multidrug-resistant organisms, such as carbapenemase producing Enterobacterales (CPE). Several sequential outbreaks of CPE on the geriatric ward of the Ghent University hospital have led to an outbreak investigation. Focusing on OXA-48 producing Citrobacter freundii, the most prevalent species, we aimed to track clonal relatedness using whole genome sequencing (WGS). By exploring transmission routes we wanted to improve understanding and (re)introduce targeted preventive measures. Methods: Environmental screening (toilet water, sink and shower drains) was performed between 2017 and 2021. A retrospective selection was made of 53 Citrobacter freundii screening isolates (30 patients and 23 environmental samples). DNA from frozen bacterial isolates was extracted and prepped for shotgun WGS. Core genome multilocus sequence typing was performed with an in-house developed scheme using 3,004 loci. Results: The CPE positivity rate of environmental screening samples was 19.0% (73/385). Highest percentages were found in the shower drain samples (38.2%) and the toilet water samples (25.0%). Sink drain samples showed least CPE positivity (3.3%). The WGS data revealed long-term co-existence of three patient sample derived C. freundii clusters. The biggest cluster (ST22) connects 12 patients and 8 environmental isolates taken between 2018 and 2021 spread across the ward. In an overlapping period, another cluster (ST170) links eight patients and four toilet water isolates connected to the same room. The third C. freundii cluster (ST421) connects two patients hospitalised in the same room but over a period of one and a half year. Additional sampling in 2022 revealed clonal isolates linked to the two largest clusters (ST22, ST170) in the wastewater collection pipes connecting the rooms. Conclusions: Our findings suggest long-term circulation and transmission of carbapenemase producing C. freundii clones in hospital sanitary installations despite surveillance, daily cleaning and intermittent disinfection protocols. We propose a role for the wastewater drainage system in the spread within and between rooms and for the sanitary installations in the indirect transmission via bioaerosol plumes. To tackle this problem, a multidisciplinary approach is necessary including careful design and maintenance of the plumbing system. [ABSTRACT FROM AUTHOR]

The Hunga Tonga Hunga Ha'apai submarine volcano has experienced repeated eruptions in the latest decades. The recent one, in January 2022, released an enormous amount of energy inducing global perturbations, as tsunamis and atmospheric waves. The structure of the volcano is poorly understood, especially its internal structure. Deep-seated magmatic connections are difficult to define or visualize. We use a high-resolution gravity data set obtained via satellite to calculate the Bouguer anomaly over its structure, to perform a preliminary exploration of its interior. Executing 3D gravity inversions, we find a complex plumbing system with various exhaust trajectories and multiple surface pockets of low-density material within the volcanic edifice; some appear to be associated with ring fractures. This is in line with the report of the 2009 eruption, described as beginning from multiple vents. We found no signs of a magma chamber within 6 km depth, although several volcanic conduits are identified from such depth to the surface. Density variations occur within a plumbing conduit or may vary from one conduit to another in the same volcano. These models yield quantitative estimates for areas of magma-water interaction, constituting a baseline to compare with structural changes to be induced in future eruptions. [ABSTRACT FROM AUTHOR]

We introduce a type of surgery decomposition of Weinstein manifolds that we call simplicial decompositions. The main result of this paper is that the Chekanov–Eliashberg dg‐algebra of the attaching spheres of a Weinstein manifold satisfies a descent (cosheaf) property with respect to a simplicial decomposition. Simplicial decompositions generalize the notion of Weinstein connected sum and we show that there is a one‐to‐one correspondence (up to Weinstein homotopy) between simplicial decompositions and so‐called good sectorial covers. As an application, we explicitly compute the Chekanov–Eliashberg dg‐algebra of the Legendrian attaching spheres of a plumbing of copies of cotangent bundles of spheres of dimension at least three according to any plumbing quiver. We show by explicit computation that this Chekanov–Eliashberg dg‐algebra is quasi‐isomorphic to the Ginzburg dg‐algebra of the plumbing quiver. [ABSTRACT FROM AUTHOR]

Let T be a tree with vertices 2 m -dimensional oriented vector bundles over S 2 m and M (T) be the boundary of the oriented manifold obtained by plumbing according to T. In this paper, we calculate linking numbers between the fiber spheres, provided M (T) is a rational homology sphere, and thereby provides a correction and completion of a work of tom Dieck. [ABSTRACT FROM AUTHOR]

The residence time of water in residential building water systems is a critical factor regarding water quality at end use. Published literature has highlighted the importance of water age in these systems and its relationship with pathogenic bacteria such as Legionella pneumophila. However, tools to measure water age in such plumbing systems are typically repurposed from other applications and include limitations that make them inappropriate for some plumbing systems. This work presents a novel means of estimating water age by assuming these systems operate without mixing. Data for this study was collected from a full-scale home equipped with an extensive array of flow meters to monitor water use. Further, 408 individual water quality samples were collected to ascertain water quality changes that take place in the plumbing. Model results show weak correlation with EPANET 2.2 (ρ = 0.666), a commonly used hydraulic modeling software. The results of the water age model were also evaluated with several variable selection tools. These analyses indicate that this method's water age results are a statistically significant (p < .05) predictor of Legionella concentrations. Model results from this approach could be used in plumbing design and/or operation to assist in managing Legionella risks. [ABSTRACT FROM AUTHOR]

Modeling premise plumbing systems requires accurate treatment of fixture specific pressure and flow rate relationships. Each fixture in a building may experience different flow rates based on variable service pressure, its unique pressure-flow behavior, and demands throughout the building. Unique experimentally derived pressure-flow parameters for four faucets, a shower/tub fixture, and toilet were developed. The Water Network Tool for Resilience (WNTR) was also used to explore the impact of premise plumbing systems on water distribution systems through two simple skeletonization cases. Minimum pressures for nodes in water distribution system models that represent demand aggregated premise plumbing systems will likely be non-zero and must capture additional pressure drop or elevation differences at the building scale and associated components, such as water meters or backflow preventers. Results showed that flow rates are impacted by pressure in these systems in complex ways, and usage and system characteristics must be considered to be modeled accurately. [ABSTRACT FROM AUTHOR]

We used the Delphi method to identify areas of consensus and disagreement in managing building water systems. One hundred and six experts were invited, 25 of whom completed both rounds. More than 95% of experts agreed that current plumbing codes are not adequate and return loop temperature should be monitored. A notably low percentage of experts agreed on the required level of chloramine (i.e., 32%) and flushing frequency (22%), despite these being common control strategies. Consensus was not achieved for temperature and disinfectant residuals, but a plurality of respondents indicated that a temperature of 55(C was appropriate and that low but detectable levels of disinfectant residuals are appropriate. After Round 2, a majority of the experts agreed that the knowledge syntheses provided were helpful and unbiased. Findings from this study will help stakeholders by providing helpful insights on plumbing code, design factors, operational factors, and water quality monitoring practices. [ABSTRACT FROM AUTHOR]

In vocational education, the learning content is often considered as concrete and specific, and the vocational learning involves physical work and interactions between participants and artefacts. Furthermore, one teacher has the overall responsibility for several students during classes in the vocational workshop at school, which means that the teacher has limited time for every single student and that the few minutes they meet become very important. However, the documented knowledge about how vocational learning is constituted in the vocational classroom and what learning content is focused on in the interaction between teachers and students is very sparse. In this study, we focus on how the enacted object of learning and its critical aspects are made relevant, when a student and teacher in a plumbing workshop session negotiate the conducting of a task in Swedish vocational education. This will be done by using CAVTA (Conversation Analysis and Variation Theory Approach) to make a close and detailed analysis of video recordings of the interaction between the student and teacher when a task is introduced in the workshop session. The results show a complex process, where the teacher alternates between parts and wholeness, using several semiotic resources at hand when highlighting the learning content. [ABSTRACT FROM AUTHOR]

The surgery theorem of Wraith states that positive Ricci curvature is preserved under surgery if certain metric and dimensional conditions are satisfied. We generalize this theorem as follows: instead of attaching a product of a sphere and a disc, we glue a sphere bundle over a manifold with a so-called core metric , a type of metric which was recently introduced by Burdick to construct metrics of positive Ricci curvature on connected sums. As applications we extend a result of Burdick on the existence of core metrics on certain sphere bundles and obtain new examples of 6-manifolds with metrics of positive Ricci curvature. [ABSTRACT FROM AUTHOR]

Tools used to predict hydraulics and water quality within premise plumbing systems have gained recent interest. An open-source Python-based tool—PPMtools—for modeling and analyzing premise plumbing systems with WNTR or EPANET is presented. A relative water age—the time water has spent in a home—study using three real-world single-family homes was used to demonstrate PPMtools. Results showed that increased use—more people or higher flow fixtures—led to a general decrease in relative water ages. However, even with more use, one user could still experience water for a drinking activity with a relative water age equal to, or longer than, the duration of the longest stagnant period (sleeping or absence from home). Simulations also showed that the general relative water ages increased if the homes were plumbed with larger diameter piping [19.1 mm (3/4 in.) versus 12.7 mm (1/2 in.)]. Hot water heaters were found to have the largest impact on relative water age. Smaller volume uses generally had more variability in relative water ages, while larger volume uses (e.g., showering) resulted in generally low relative water ages with less variability because larger uses fully replaced water in the home with water from the main. This study highlights the potential for using PPMtools to explore more complex water quality modeling within premise plumbing systems. The time water spends (its relative age) in a premise plumbing system (home or building) provides a simple metric for estimating water quality. PPMtools was developed as a framework for simulating premise plumbing systems and was demonstrated using a water age study. PPMtools provides a tool for using EPANET to model these systems and handles fixture, activity, and agent (person or device) level information for model generation and analyzing results. This work demonstrates preliminary findings for three single-family homes with their EPANET input files and discusses their general implications. PPMtools can be used to study other premise plumbing water topics with additional work, where this work demonstrates the foundational work on PPMtools' development. These results highlight some general trends associated with occupancy level, plumbing sizing, and the impact of low-flow fixtures, and they are discussed in terms of their impact on relative water ages. Results highlight that simplified metrics may fail to capture the full complexity of estimating water age or interuse stagnation periods. [ABSTRACT FROM AUTHOR]

The Late Aptian Rajmahal Traps originated through Kerguelen-Plume-related volcanism at the eastern margin of the Indian Shield. Clinopyroxene and whole-rock thermobarometry reveals that the Rajmahal magmas crystallized at P-T conditions of ≤~5 kbar/~1100–1200 °C. These pressures correspond to upper crustal depths (≤~19 km). Modeling shows that the Rajmahal primary magmas were last in equilibrium with mantle at P-T conditions of ~9 kbar/~1280 °C. The corresponding depths (~33 km) are consistent with gravity data that indicate a high-density layer at lower crustal depths below an upwarped Moho. Thus, the high-density layer probably represents anomalous mantle. It is likely that the mantle-derived magmas accumulated below the upwarped Moho and were subsequently transported via trans-crustal faults/fractures to the upper crust where they evolved by fractional crystallization in small staging chambers before eruption. In the lower part of the Rajmahal plumbing system, buoyant melts from the Kerguelen Plume may have moved laterally and upward along the base of the lithosphere to accumulate and erode the eastern Indian lithospheric root. The Rajmahal plumbing system was probably shaped by tectonic forces related to the breakup of Gondwana. [ABSTRACT FROM AUTHOR]

Federal and local campaigns to reform "distressed" high-rise public housing in the late twentieth century resulted in the elimination of thousands of public housing units from cities like Baltimore. Those reform campaigns often defined "distress" in cultural terms, imagining Black women residents as imperiled actors, public housing as an impediment to building normative family life, and housing demolition and privatization as a necessary and normalizing corrective. Oral histories with residents living in these disinvested spaces offer counternarratives and demonstrate how Black women residents theorized their own conditions, fashioned material political demands independent of policy makers and housing reformers, and worked to put these demands into practice. This piece reflects on the mutual aid organizing of two former residents of Baltimore's George B. Murphy Homes. Specifically, it analyzes the practical work they did to address the conditions that disinvestment produced, and the intellectual work they did to fashion a materialist vision for housing reform that pushed back against the drive toward demolition and privatization. [ABSTRACT FROM AUTHOR]

We review pre-eruptive dynamics and evidence of open-system behavior in the volcanic plumbing system beneath Campi Flegrei Caldera, together with estimates of magma residence time, magma ascent, and mixing-to-eruption timescales. In detail, we compile pre- and syn-eruptive dynamics reported in the literature for (a) the Campanian Ignimbrite ~ 40 ka, (b) the Neapolitan Yellow Tuff (~ 15 ka), and (c) the recent activity within the Phlegrean area. We first summarize geochemical and textural evidence (e.g., magma mixing, crystal disequilibria, vertical zonings, and isotopic records) of open-system behavior for the pyroclasts erupted in the last 40 ky at Campi Flegrei Caldera. We show that the fingerprint of open-system dynamics is ubiquitous in the deposits associated with the volcanic activity at the Campi Flegrei Caldera in the last 40 ky. Then, we describe the results of geophysical and petrological investigations that allow us to hypothesize the structure of the magma feeding system. We point to a trans-crustal magmatic feeding system characterized by a main storage reservoir hosted at ~ 9 km that feeds and interacts with shallow reservoirs, mainly placed at 2–4 km. Finally, we define a scenario depicting pre-eruptive dynamics of a possible future eruption and provide new constraints on timescales of magma ascent with a physical model based on magma-driven ascending dyke theory. Results show that considerably fast ascent velocities (i.e., of the order of m/s) can be easily achieved for eruptions fed by both shallow (i.e., 3–4 km) and deep (i.e., ~ 9 km) reservoirs. Comparing the results from experimental and numerical methods, it emerges that mixing-to-eruption timescales occurring at shallow reservoirs could be on the order of minutes to hours. Finally, we highlight the volcanological implications of our timescale estimates for magma ascent and mixing to eruption. In particular, explosive eruptions could begin with little physical 'warning', of the order of days to months. In this case, the onset of volatile saturation might provide pre-eruptive indicators. [ABSTRACT FROM AUTHOR]

The paper presents Fuzzy Inference System (FIS) -based approach to estimating probable flows for sizing building water supply pipes. Instead of calculating the design flow by estimating the number of fixtures operating simultaneously using probabilistic or deterministic approach utilizing a large amount of high-resolution field data, the proposed methodology uses Fuzzy logic to estimate demand characteristics of fixtures, unlike conventional fixture unit method. The developed methodology is based on FISs derived from users' socio-demographic characteristics, their diurnal activities and water use habits. A MATLAB program was developed to estimate the probable flows through the pipe using inputs-type of accommodation, connected fixture types and fixture flow rates. An imaginary 7-storey residential building with a gravity tank system was considered for pipe sizing. The design flows obtained by the proposed methodology were 50–70% of the those produced by the fixture unit approach leading to smaller pipe sizes. [ABSTRACT FROM AUTHOR]

The article discusses a research study on the geophysical community where global seismic tomography has provided evidence for the presence of broad plume-like conduits rooted at the core-mantle boundary within the two large low–shear velocity provinces beneath the Pacific and Africa. It is noted that several lowermantle plumes appear to feed the same low–seismic velocity ponding zone in the lower-mantle extension of the transition zone in the depth range of 660 to 1000 km.

Nishiyama volcano on Hachijojima Island is an active basaltic volcano located in the Izu–Bonin arc. In this study, petrological and geochemical analyses were conducted on mafic lavas and pyroclastics to understand the magma plumbing system and pre-eruption magmatic processes. Whole-rock major element compositions show significant variations (49.4–54.9 wt.% SiO2), and the samples contain variable amounts of plagioclase phenocrysts (1–40 vol.%). The whole-rock Sr, Nd, and Pb isotopic compositions of samples from the youngest volcanic stage (< 0.7 ka) are homogeneous, whereas some samples from the older stage (3–1 ka) have relatively low Pb isotopic ratios. This observation suggests that the younger magmas were derived from a single parental magma, but another parental magma with distinct geochemical features was involved in the magmatic system before 1 ka. The temporal variation in the FeO*/MgO ratios of the volcanic products is complex and is considered to reflect the intermittent injection of primitive magmas into the main magma chamber in which fractional crystallization occurred. Two-pyroxene geobarometry suggests that the main magma chamber was located at a depth of 9–12 km. The core region of some plagioclase phenocrysts consists of a glass inclusion-free inner core and an inclusion-rich outer mantle, suggesting that some plagioclase crystallized in the main magma chamber, which was followed by overgrowth during magma ascent because of increasing liquidus temperatures due to decompression-induced water exsolution from the melt. The whole-rock compositions of some eruption units with different Al2O3/MgO ratios exhibit distinct plagioclase-controlled trends, which negates the possibility that plagioclase accumulation occurred in a stable magma chamber. In addition, the density of plagioclase was higher than that of the melt during the magma ascent to the surface. From these observations, it is suggested that the accumulation of plagioclase phenocrysts occurred in ascending magmas as the plagioclase settled relative to the surrounding melt. The estimated depth of 9–12 km for the main magma chamber coincides with the depth range over which earthquake swarms occurred in 2002, suggesting that the magma chamber is still active, and that the earthquake swarms may reflect the injection of primitive magma into the magma chamber. [ABSTRACT FROM AUTHOR]

Following the 2021 Marshall Fire in Colorado, this study was conducted to better understand private well and plumbing damage and to develop public health guidance. More than 20 post‐fire drinking water well guidance documents with varied recommendations were found. Approximately 227 wells were located in the fire footprint. Seventeen properties were visited, and a subset of wells were sampled for organic and inorganic contaminants. Property debris was also collected. Benzene, toluene, and 19 semi‐volatile organic compounds (SVOCs) were detected in water extracts of property debris. No wells contained volatile organic compound contamination. Two shallow wells (12 and 15 ft) had debris contamination; one well contained notable SVOC contamination. One multi‐home unregulated well system was extensively damaged, lost pressure, and had not been repressurized 11 months after the fire due to financial and technical challenges. Study results highlight the need for follow‐up work to understand well system damage and household response. [ABSTRACT FROM AUTHOR]

Prefabrication is often considered as a potential solution to address the challenges of building construction in remote communities. However, methods to find the best modularization for mechanical, electrical, and plumbing (MEP) systems are scarce. This prevents a proper assessment of cost reductions and local benefits, two key metrics for decision makers in remote communities. Therefore, in this study a computational framework is proposed for identifying the optimal modularity of piping to be assembled in residential buildings located in an isolated region, namely Nunavik (Quebec). The framework contributes to advancing existing modularity optimization approaches for MEP systems by integrating two objective functions, the impact of module characteristics on modularization, collision constraints during assembly, and the context of remote communities. The algorithm simultaneously minimizes system installation cost and maximizes local job creation, an important socioeconomical outcome of construction in remote areas. Fuzzy logic models and nondominated sorting genetic algorithm (NSGA-II) algorithm were used to evaluate configurations and identify nondominated solutions. Type of work, height of the assembly, direction changes, and stiffness of the modules were considered in estimating assembly time. The dimensions and weight of each module were used to estimate handling time. The optimization framework considers two possible prefabrication sites, outside and inside the remote region. By applying this approach to modularize an MEP system in typical Nunavik housing units, it was possible to demonstrate a reduction in installation cost and an increase in local job creation compared to the current situation (i.e., without MEP prefabrication). In particular, for a case study with 40 components, the proposed framework found a solution that can reduce installation cost by 81.9% and generate 23.4 h of local employment. [ABSTRACT FROM AUTHOR]

• Field studies comparing disinfectants rank the typical efficacy against Legionella as chloramine > chlorine dioxide > chlorine. • Disinfection concentration on its own is not the deciding factor for the disinfectant efficacy against Legionella. • A total of 16 different factors potentially influenced the antibacterial efficacy of the chlorine-based disinfectants. • A total of 21 factors were identified as influencing the rate of decay of disinfectants in premise plumbing systems. • Future research is needed to measure and model these factors in premise plumbing systems to improve Legionella control. Legionella is an opportunistic waterborne pathogen that causes Legionnaires' disease. It poses a significant public health risk, especially to vulnerable populations in health care facilities. It is ubiquitous in manufactured water systems and is transmitted via inhalation or aspiration of aerosols/water droplets generated from water fixtures (e.g., showers and hand basins). As such, the effective management of premise plumbing systems (building water systems) in health care facilities is essential for reducing the risk of Legionnaires' disease. Chemical disinfection is a commonly used control method and chlorine-based disinfectants, including chlorine, chloramine, and chlorine dioxide, have been used for over a century. However, the effectiveness of these disinfectants in premise plumbing systems is affected by various interconnected factors that can make it challenging to maintain effective disinfection. This systematic literature review identifies all studies that have examined the factors impacting the efficacy and decay of chlorine-based disinfectant within premise plumbing systems. A total of 117 field and laboratory-based studies were identified and included in this review. A total of 20 studies directly compared the effectiveness of the different chlorine-based disinfectants. The findings from these studies ranked the typical effectiveness as follows: chloramine > chlorine dioxide > chlorine. A total of 26 factors were identified across 117 studies as influencing the efficacy and decay of disinfectants in premise plumbing systems. These factors were sorted into categories of operational factors that are changed by the operation of water devices and fixtures (such as stagnation, temperature, water velocity), evolving factors which are changed in-directly (such as disinfectant concentration, Legionella disinfectant resistance, Legionella growth, season, biofilm and microbe, protozoa, nitrification, total organic carbon(TOC), pH, dissolved oxygen(DO), hardness, ammonia, and sediment and pipe deposit) and stable factors that are not often changed(such as disinfectant type, pipe material, pipe size, pipe age, water recirculating, softener, corrosion inhibitor, automatic sensor tap, building floor, and construction activity). A factor-effect map of each of these factors and whether they have a positive or negative association with disinfection efficacy against Legionella in premise plumbing systems is presented. It was also found that evaluating the effectiveness of chlorine disinfection as a water risk management strategy is further complicated by varying disinfection resistance of Legionella species and the form of Legionella (culturable/viable but non culturable, free living/biofilm associated, intracellular replication within amoeba hosts). Future research is needed that utilises sensors and other approaches to measure these key factors (such as pH, temperature, stagnation, water age and disinfection residual) in real time throughout premise plumbing systems. This information will support the development of improved models to predict disinfection within premise plumbing systems. The findings from this study will inform the use of chlorine-based disinfection within premise plumbing systems to reduce the risk of Legionnaires disease. [Display omitted] [ABSTRACT FROM AUTHOR]

An article (Gennaro et al., 2023, 456–457, 107325) recently published in Lithos proposes a model for the transcrustal magmatic plumbing system at the Marsili Seamount, a massive and still active volcanic centre at the Southern Tyrrhenian back-arc spreading ridge. Their model is based on a combination of geophysical and petrochemical data, the former confined to the axial zone of the Marsili volcano while the latter mostly refer to literature data dealing with samples collected from various sectors of the volcano. This comment questions the rationality of the proposed model, documenting that it is poorly constrained and, at places, incorrect. [ABSTRACT FROM AUTHOR]