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Abstract In the rate‐state friction law framework, the transition from velocity weakening (V‐W) to velocity strengthening (V‐S) behavior marks the base of the seismogenic crust. Here we investigate the role of fault slip displacement under hydrothermal conditions in controlling the V‐W to V‐S transition. We shear simulated gabbro gouges at slip velocities ranging from 16 nm/s (∼50 cm/year) to 10 μm/s (∼8 cm/day) under hydrothermal conditions (300–400°C temperature; 30 MPa pore fluid pressure). We observe that cumulative fault slip increases the critical velocity for the V‐W to V‐S transition. The transition is accompanied by localized to distributed deformation mode, the formation of smectite‐type clays and occurrence of intergranular mass transfer. Our results provide insights into understanding the deepening and shallowing of V‐W/V‐S boundary (lower limit of the seismogenic zone) following a mainshock. Besides strain rate effects, slip‐enhanced chemical alteration and grain size‐sensitive deformation may temporarily contribute to the shallowing process.

Abstract Earthquakes often occur along faults in the presence of hot, pressurized water. Here we exploit a new experimental device to study friction in gabbro faults with water in vapor, liquid and supercritical states (water temperature and pressure up to 400 °C and 30 MPa, respectively). The experimental faults are sheared over slip velocities from 1 μm/s to 100 mm/s and slip distances up to 3 m (seismic deformation conditions). Here, we show with water in the vapor state, fault friction decreases with increasing slip distance and velocity. However, when water is in the liquid or supercritical state, friction decreases with slip distance, regardless of slip velocity. We propose that the formation of weak minerals, the chemical bonding properties of water and (elasto)hydrodynamic lubrication may explain the weakening behavior of the experimental faults. In nature, the transition of water from liquid or supercritical to vapor state can cause an abrupt increase in fault friction that can stop or delay the nucleation phase of an earthquake.

The use of lumpfish (Cyclopterus lumpus L.) as cleaner fish in Atlantic salmon aquaculture has emerged as a promising solution to combat the issue of sea lice infestation, as they have proven effective under the right conditions. The aquaculture industry, however, is facing challenges in ensuring the welfare and survival of lumpfish in salmon cages. Part of the welfare monitoring of lumpfish is the estimation of body condition. Previous research on standard length-weight relationships for lumpfish has primarily relied on the growth patterns of lumpfish in salmon cages, which might not align with the natural growth patterns of the fish. In this study, we argue for another perspective: using the standard weight of wild lumpfish to estimate the body condition of lumpfish in salmon cages. We assert that this approach aligns more closely with the natural growth pattern of the fish and may offer a more accurate representation of their condition. Our findings show significant differences in growth patterns between wild lumpfish, which show positive allometric growth, and those in salmon cages, which show slightly negative allometric growth. The findings underscore the importance of using appropriate length-weight relationships for lumpfish in aquaculture to ensure an accurate assessment of their body condition.

Abstract Seismic ruptures often propagate along fault zones cutting km‐thick sequences of carbonates (e.g., Wenchuan Mw 7.8, 2008, China; L’Aquila Mw 6.1, 2009, Italy). As a consequence, fault rock assemblages may record the seismic cycle under a wide range of loading conditions, temperatures (>1,000°C during co‐seismic slip), and fluid‐rock interactions. The Monte Camicia Thrust Zone in the Italian Central Apennines is exhumed from ∼3 km depth. We studied the seismic cycle recorded by a network of faults cutting bituminous dolostones in the footwall of the Monte Camicia Thrust. These faults accommodate up to several meters of displacement. Slip zones are mm‐ to cm‐thick and bounded by ultra‐polished (“mirror‐like”) surfaces independently of their displacement. At the microscale, deformation is accommodated by cataclasis and pressure‐solution in carbonates, and viscous flow in the foliated bitumen. Some of the faults with displacements >0.10 m have multiple slip zones, separated by “mirror‐like” surfaces, and include clasts of foliated bitumen and fragments of older slip zones sealed by calcite precipitation. We conclude that (a) slip zones record post‐ to inter‐seismic (foliated bitumen) and co‐seismic (fragments of bitumen) deformation in a fluid‐rich environment (calcite precipitation) and (b) mirror‐like surfaces formed during all phases of the seismic cycle.

This paper presents experimental evidence of thermal pressurization (TP) weakening of seismic faults, and suggests TP processes could be significantly promoted by wear-induced sealing during earthquakes even for relatively permeable faults.

Introduction Prevention of cardiovascular disease (CVD) is of key importance in reducing morbidity, disability and mortality worldwide. Observational studies suggest that digital health interventions can be an effective strategy to reduce cardiovascular (CV) risk. However, evidence from large randomised clinical trials is lacking.Methods and analysis The CV-PREVITAL study is a multicentre, prospective, randomised, controlled, open-label interventional trial designed to compare the effectiveness of an educational and motivational mobile health (mHealth) intervention versus usual care in reducing CV risk. The intervention aims at improving diet, physical activity, sleep quality, psycho-behavioural aspects, as well as promoting smoking cessation and adherence to pharmacological treatment for CV risk factors. The trial aims to enrol approximately 80 000 subjects without overt CVDs referring to general practitioners’ offices, community pharmacies or clinics of Scientific Institute for Research, Hospitalization and Health Care (Italian acronym IRCCS) affiliated with the Italian Cardiology Network. All participants are evaluated at baseline and after 12 months to assess the effectiveness of the intervention on short-term endpoints, namely improvement in CV risk score and reduction of major CV risk factors. Beyond the funded life of the study, a long-term (7 years) follow-up is also planned to assess the effectiveness of the intervention on the incidence of major adverse CV events. A series of ancillary studies designed to evaluate the effect of the mHealth intervention on additional risk biomarkers are also performed.Ethics and dissemination This study received ethics approval from the ethics committee of the coordinating centre (Monzino Cardiology Center; R1256/20-CCM 1319) and from all other relevant IRBs and ethics committees. Findings are disseminated through scientific meetings and peer-reviewed journals and via social media. Partners are informed about the study’s course and findings through regular meetings.Trial registration number NCT05339841.

The use of lumpfish (Cyclopterus lumpus L.) as cleaner fish in Atlantic salmon aquaculture has emerged as a promising solution to combat the issue of sea lice infestation, as they have proven effective under the right conditions. The aquaculture industry, however, is facing challenges in ensuring the welfare and survival of lumpfish in salmon cages. Part of the welfare monitoring of lumpfish is the estimation of body condition. Previous research on standard length-weight relationships for lumpfish has primarily relied on the growth patterns of lumpfish in salmon cages, which might not align with the natural growth patterns of the fish. In this study, we argue for another perspective: using the standard weight of wild lumpfish to estimate the body condition of lumpfish in salmon cages. We assert that this approach aligns more closely with the natural growth pattern of the fish and may offer a more accurate representation of their condition. Our findings show significant differences in growth patterns between wild lumpfish, which show positive allometric growth, and those in salmon cages, which show slightly negative allometric growth. The findings underscore the importance of using appropriate length-weight relationships for lumpfish in aquaculture to ensure an accurate assessment of their body condition. [ABSTRACT FROM AUTHOR]

Legacy brominated flame retardants, including polybrominated diphenyl ethers (PBDEs), have been classified as persistent organic pollutants and replaced with novel brominated flame retardants (NBFRs). The octanol–water partition coefficients (log KOW) of NBFRs have been computationally estimated, but the log KOW values provided by these methods can differ by 1 to 3 orders of magnitude. Given the importance of this parameter in fate and toxicity models, we indirectly measured the log KOW values of eight NBFRs by their capacity factor (k′) on a reversed‐phase high‐performance liquid chromatography (HPLC) C18 column by isocratic elution and compared these measured values with those estimated by nine computational models. Log KOW values were obtained for the NBFRs 1,2‐bis(2,4,6‐tribromophenoxy) ethane, pentabromobenzene, pentabromoethylbenzene, pentabromotoluene, 2‐ethylhexyl 2,3,4,5‐tetrabromobenzoate, allyl 2,4,6‐tribromophenylether, 2,3‐dibromopropyl‐2,4,6‐tribromophenyl ether, and bis(2‐ethylhexyl) tetrabromophthalate. A training set of phthalates, polychlorinated biphenyls, PBDEs, and halogenated benzenes were chosen to obtain the log k′–log KOW calibration for the NBFRs. The computational models KowWIN, XLogP3, EAS‐E Suite, COSMOtherm, DirectML, and Abraham polyparameter linear free energy relationships all predicted the log KOW values of the calibration compounds to within 1 order of magnitude without significant bias. The median of these models predicted log KOW values for the calibration compounds that were close to those known in the literature with root mean square error (RMSE) = 0.224 and for the NBFRs that were close to those measured by HPLC (RMSE = 0.334). Environ Toxicol Chem 2024;43:2105–2114. © 2024 SETAC [ABSTRACT FROM AUTHOR]

Earthquakes are frictional instabilities caused by the shear stress decrease, that is, dynamic weakening, of faults with slip and slip rate. During dynamic weakening, shear stress depends on slip, slip rate, and temperature, according to constitutive laws governing the earthquake rupture process. In the laboratory, technical limitations in measuring temperature during frictional instabilities inhibit the investigation and interpretation of shear stress evolution. Here we conduct high velocity friction experiments on calcite‐bearing simulated faults, both on bare‐rock and on gouge samples, at 20–30 MPa normal stress, 1–6 m/s slip rate and 1–20 m total slip. Seismic slip pulses are reproduced by imposing boxcar and regularized Yoffe slip rate functions. We measured, together with shear stress, slip, and slip rate, the temperature evolution on the fault by employing an innovative two‐color fiber optic pyrometer. The comparison between modeled and measured temperature reveals that for calcite‐bearing faults the heat sink caused by decarbonation reaction controls the temperature evolution. In bare‐rocks, energy is dissipated as frictional heat, and temperature increase is buffered by the heat sink of the calcite decarbonation reaction. In gouges, energy is dissipated as frictional heat and for plastic deformation processes, balanced by the heat sink caused by the decarbonation reaction enhanced by the mechanochemical effect. Our results suggest that in calcite‐bearing rocks, a common fault zone material for earthquake sources in the continental crust at shallow depth, the type of fault materials (bare‐rocks vs. gouges) controls the energy dissipation during seismic slip. Plain Language Summary: During earthquakes, faults rocks lose strength, and therefore the ability to sustain shear stress as a consequence of slip, slip rate, and temperature resulting in dynamic weakening. The mathematical relationships between the decreasing strength and slip, slip rate, and temperature and the energy balance describing the partition of energy are of fundamental importance to model the propagation of an earthquake rupture. These relationships can be defined thanks to laboratory experiments that simulate seismic slip. Here, we tested calcite‐bearing fault rocks simulated as bare‐rock and gouges. During the experiments, temperature was monitored thanks to an innovative measuring system. Numerical models were done assuming all mechanical energy was converted into heat. By comparing all results above, we discovered that the mechanical energy in both bare‐rocks and gouges is converted to heat but limited by the occurrence of endothermic decarbonation reaction. In gouges, also an energy contribution for plastic deformation processes is required. Our work implies significant changes in the commonly accepted energy budget for earthquake propagation and show the importance of slip rate and temperature in driving together the dynamic weakening during seismic slip. Key Points: We measure temperature, shear stress, and slip rate to assess energy dissipation during seismic slip in calcite‐bearing fault materialsCalcite decarbonation compensates frictional heat production in all tested fault materialsMechanical energy is dissipated for frictional heat in bare‐rocks and for frictional heat and plastic deformation processes in gouges [ABSTRACT FROM AUTHOR]

Objectives: This study aims to demonstrate the role of case-level American College of Medical Genetics (ACMG) criteria, such as familial segregation and pathology data, in providing conclusive evidence for the pathogenicity of ultrarare GLA variants causing Anderson–Fabry disease when gene-level and variant-level criteria provide ambiguous or discrepant results. Case/family description: A 52-year-old woman presented with new-onset shortness of breath, chest pain, and palpitations. Echocardiography revealed mild left ventricular wall thickening (14 mm) and mild diastolic dysfunction. She was the second of three siblings born to unrelated parents, both of whom died from malignancies. Family screening identified brothers, one affected 55-year-old with hypertension and asthma and one unaffected 47-year-old. The 15-year-old son of the proband complained of exercise-induced burning feet acral pain his electrocardiogram showed a short PR interval and signs of early hypertrophy. Results: Endomyocardial biopsies of the proband and the affected sibling demonstrated substrate accumulation (globotriaosylceramide). The anti-α-galactosidase-A immunostain showed a total loss of the enzyme in the hemizygous male and a mosaic pattern in the heterozygous female. The next-generation sequencing short-read multigene panel identified the c.547+3A>G variant in the GLA gene and excluded variants in other genes; Oxford-Nanopore long-read sequencing excluded known pathogenic deep intronic variants. A Multiplex-Ligation-dependent-Probe-Amplification assay excluded copy number variations. Based on the variant-level and gene-level ACMG criteria, the variant was classified as a Variant of Uncertain Significance or Likely Benign using different bioinformatic tools. By adding case-level functional data (endomyocardial biopsy, PS3_VeryStrong) and familial data (segregation of genotype with phenotype, PP2_Moderate), the variant was classified as Likely Pathogenic/Pathogenic. Conclusion: ACMG case-level data can unambiguously resolve uncertain interpretations of GLA variants. [ABSTRACT FROM AUTHOR]

Abstract Background A breastfeeding-friendly physician’s office that applies the 13 recommendations of the Academy of Breastfeeding Medicine can help increase the exclusivity and duration of breastfeeding. Having already published the results up to five months of age of this intervention in our pediatric practice, we now report on the follow up to 36 months. Methods A cohort of 252 newborn infants was enrolled with our pediatric office in Trieste, Italy, between 1 January 2016 and 31 December 2016. The office implemented baby-friendly pediatric practices and a biological nurturing approach to the support of breastfeeding. In addition to the services offered by two pediatricians, support was provided by a peer counselor. Data on breastfeeding were collected at periodic healthy child visits up to 36 months of age. The outcome of interest for this follow up was the rate of any breastfeeding, defined as the percentage of infants and children who had received breastmilk in the previous 24 h. Results The rates of any breastfeeding at discharge and at 1, 3 and 5 months (n = 252) were 95.2, 95.8, 89.3 and 86.5%, respectively. At 8, 12, 18, 24 and 36 months of age, the rates of breastfeeding were 70.6% (163/231), 59% (135/229), 35% (78/224), 24.6% (55/224) and 7.2% (16/224), respectively. Conclusions The rates of any breastfeeding recorded in our pediatric practice up to age 36 months, are much higher than those reported elsewhere in high income countries and are likely to be associated with our baby-friendly and biological nurturing approach.

Laboratory experiments reproducing earthquake slip in non cohesive fault rocks under fluid pressurised conditions are challenging. Thanks to these experiments, the authors show that earthquake slip occurring in tsunamigenic subduction zone faults is controlled by dilatancy and pressurisation processes.

Calcite and dolomite are the two most common minerals in carbonate-bearing faults and shear zones. Motivated by observations of exhumed seismogenic faults in the Italian Central Apennines, we used a rotary-shear apparatus to investigate the frictional and microstructural evolution of ca. 3 mm thick gouge layers consisting of 50 wt % calcite and 50 wt % dolomite. The gouges were sheared at a range of slip rates (30 µm s−1–1 m s−1), displacements (0.05–0.4 m), and a normal load of 17.5 MPa under both room-humidity and water-dampened conditions. The frictional behaviour and microstructural evolution of the gouges were strongly influenced by the presence of water. At room humidity, slip strengthening was observed up to slip rates of 0.01 m s−1, which was associated with gouge dilation and the development of a 500–900 µm wide slip zone cut by Y-, R-, and R1-shear bands. Above a slip rate of 0.1 m s−1, dynamic weakening accompanied the development of a localised < 100 µm thick principal slip zone preserving microstructural evidence for calcite recrystallisation and dolomite decarbonation, while the bulk gouges developed a well-defined foliation consisting of organised domains of heavily fractured calcite and dolomite. In water-dampened conditions, evidence of gouge fluidisation within a fine-grained principal slip zone was observed at a range of slip rates from 30 µm s−1 to 0.1 m s−1, suggesting that caution is needed when relating fluidisation textures to seismic slip in natural fault zones. Dynamic weakening in water-dampened conditions was observed at 1 m s−1, where the principal slip zone was characterised by patches of recrystallised calcite. However, local fragmentation and reworking of recrystallised calcite suggests a cyclic process involving formation and destruction of a heterogeneous slip zone. Our microstructural data show that development of well-defined gouge foliation under the tested experimental conditions is limited to high velocities (>0.1 m s−1) and room humidity, supporting the notion that some foliated gouges and cataclasites may form during seismic slip in natural carbonate-bearing faults.

In the rate‐state friction law framework, the transition from velocity weakening (V‐W) to velocity strengthening (V‐S) behavior marks the base of the seismogenic crust. Here we investigate the role of fault slip displacement under hydrothermal conditions in controlling the V‐W to V‐S transition. We shear simulated gabbro gouges at slip velocities ranging from 16 nm/s (∼50 cm/year) to 10 μm/s (∼8 cm/day) under hydrothermal conditions (300–400°C temperature; 30 MPa pore fluid pressure). We observe that cumulative fault slip increases the critical velocity for the V‐W to V‐S transition. The transition is accompanied by localized to distributed deformation mode, the formation of smectite‐type clays and occurrence of intergranular mass transfer. Our results provide insights into understanding the deepening and shallowing of V‐W/V‐S boundary (lower limit of the seismogenic zone) following a mainshock. Besides strain rate effects, slip‐enhanced chemical alteration and grain size‐sensitive deformation may temporarily contribute to the shallowing process. Plain Language Summary: According to the standard model of earthquake nucleation, earthquakes are the result of frictional instabilities along faults. The necessary condition for earthquake nucleation is that the frictional strength of a fault decreases with fault slip velocity ("velocity‐weakening" behavior) or slip distance ("slip‐weakening" behavior). Although extensive laboratory studies have been conducted to investigate the velocity‐dependence of friction in rocks, less attention was paid to the role of slip displacement on fault frictional stability, especially in the presence of hot and pressurized fluids. The latter, difficult to reproduce in the laboratory, is a common condition at seismogenic depths. In this study, we examine how the frictional stability evolves with slip velocity and displacement on simulated faults made of powders of gabbro (a common rock of the oceanic crust) under hydrothermal conditions up to 400°C. We find that the critical velocity for the transition from velocity‐weakening to velocity‐strengthening increases with cumulative slip displacement. In nature, the increase of this critical velocity may result in the uplift, during seismic sequences, of the base of the seismogenic crust (i.e., aftershock hypocenters will be shallower). Our findings suggest that, slip displacement, accompanied by fault mineralogical‐structural evolution, can influence fault frictional stability and earthquake nucleation. Key Points: The role of slip displacement in controlling fault stability under hydrothermal conditions is investigatedThe critical velocity for transition in friction from velocity‐weakening to velocity‐strengthening increases with slip displacementThis frictional transition, attributed to chemical alteration, is accompanied by the transition from localized to delocalized deformation [ABSTRACT FROM AUTHOR]

Natural fault zones are complex, spatially heterogeneous systems. Rock deformation experimental studies simplify the complexity of natural fault zones either as a surface discontinuity between intact rocks (bare‐rock surfaces) or as a few mm‐thick gouge layer. However, depending on the simplified fault type and its slip history, the response to applied deformation can vary. In this work, we conduct laboratory experiments for investigating the evolution of mechanical parameters of simulated faults made of calcite gouge subjected to multiple (four) identical seismic slip‐rate pulses. We observed that, as the number of applied slip‐rate pulses increased, (a) initial friction and steady‐state friction remained approximatively constant, (b) peak friction and normalized strength excess increased and, (c) the slip distances to achieve peak and steady‐state friction, Da and Dc, decreased. The greatest changes occurred between the first and the second slip‐rate pulse. From this pulse onward, the dissipated energy of the calcite gouge fault was similar to those obtained in bare‐rock surfaces experiments. Microstructural analysis showed that, strain is localized in up to two (recrystallized) principal slip zones (PSZ) with sub‐micrometric grain size, surrounded by low porosity sintered and non‐sintered comminuted gouge domains. We conclude that previous seismic slip episodes impact on both the structure and the strain localization processes within a fault, contributing to its shear fabric evolution. We highlight that the strain localization process identifies the PSZ, dissipating the least amount of energy within the entire experimental fault zone. Plain Language Summary: Earthquakes are caused by the propagation of seismic ruptures and sliding of rocks along geological structures called faults. Within the fault, seismic ruptures propagate in mm‐cm thick slip zones that cut cm‐ to meters‐thick fault cores. Both slip zones and fault cores typically exhibit microstructural assemblages different from those of nearby rocks. Laboratory experiments are used to investigate the processes that result in the decrease of fault strength with slip and slip‐rate and govern seismic rupture propagation. However, experiments are performed on simplified fault cores consisting of either a surface discontinuity between intact rocks (i.e., slip zone = "bare‐rock surfaces") or a mm‐thick layer of powdered rocks (i.e., slip zone in a "fault gouge"). In this work, we investigate how slip zones form and evolve in an experimental fault (gouge) core depending on seismic slip history. We apply repeated pulses of seismic slip and show that (a) in the first pulse a slip zone with similar microstructure and friction properties to bare‐rock is formed, (b) in subsequent pulses these slip zones are abandoned and new slip zones are formed in the fault core. Notably, these structural changes, occur to minimize the mechanical energy dissipated in the FC. Key Points: Friction experiments applying up to four consecutive seismic slip‐rate pulses (1 m/s), in fault gouge and bare‐rock surfacesThe greatest changes in dissipated energy occurred between the first and the second slip‐rate pulseStrain localization in the principal slip zones minimizes the energy dissipated within the whole experimental fault zone [ABSTRACT FROM AUTHOR]