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Mechanisms by which hydrochemical changes occur after earthquakes are not well documented. We use the 2016–2017 central Italy seismic sequence, which caused notable hydrochemical transient variations in groundwater springs to address this topic, with special reference to effects on fractured carbonate aquifers. Hydrochemistry measured before and after the earthquakes at four springs at varying distances from the epicenters all showed immediate postmainshock peaks in trace element concentrations but little change in major elements. Most parameters returned to preearthquake values before the last events of the seismic sequence. The source of solutes, particularly trace elements, is longer residence time pore water stored in slow‐moving fractures or abandoned karstic flow paths. These fluids were expelled into the main flow paths after an increase in pore pressure, hydraulic conductivity, and shaking from coseismic aquifer stress. The weak response to the later earthquakes is explained by progressive depletion of high solute fluids as earlier shocks flushed out the stored fluids in the fractures. Spring δ13CDICvalues closest to a deep magma source to the west became enriched relative to preearthquake values following the 24 August event. This enrichment indicates input from deeply sourced dissolved CO2gas after dilation of specific fault conduits. Differences in carbon isotopic responses between springs are attributed to proximity to the deep gaseous CO2source. Most of the transient chemical changes seen in the three fractured carbonate aquifers are attributed to local shaking and emptying of isolated pores and fractures and are not from rapid upward movement of deep fluids. Understanding the mechanisms of chemical and fluid transport to groundwater springs after earthquakes is poorly understood. Recent earthquakes in the Apennine mountains of central Italy provide a unique example of pre and post earthquake changes to groundwater chemistry in different carbonate aquifers. Our data show that changes were temporary for about 4 months after the earthquakes and that distance from the earthquake gave different responses. We show that the cause of these temporary changes was caused by shaking of long residence time local water into the fast moving flow. Once this long residence time water was flushed from the system the chemistry returned to background concentrations. We found little evidence of precursor chemical changes and no change in arsenic, which had been reported elsewhere. We did find changes in carbon dioxide gas in some springs that indicated that where a deep source of this gas existed, that it could quickly be released to the springs. These findings have implications for water supply delivery immediately after earthquakes and show that local shaking is likely more important than fluids derived from deep sources. Transient changes in trace elements after earthquakes in fractured carbonate aquifers are due to local ground shaking not deep fluid movementChanges in carbon isotopic ratio in some springs near a deep magma source indicate release of dissolved CO2gas after shakingShaking out long residence time water from isolated pores and fractures into the main flow path is the reason for the transient response

Here we present, for the first time in the Po Plain foredeep (Northern Italy), the middle to late Pleistocene growth history of an outcropping secondary fold and related faults, whose progressive deformation over an intermediate time window (105years) is driven by an underlying seismogenic blind thrust. We trenched and logged an outcropping decametric secondary anticline, related to a deeper blind compressional structure, which deforms fluvial sediments and an overlying loess‐paleosol sequence. Folded units were dated, using radiocarbon and optically stimulated luminescence methods, to the late Pleistocene–Holocene and tentatively correlated with glacial‐interglacial phases occurring during the time interval from marine isotope stage 6 to the present. A multistep retrodeformation of the fold allowed us to calculate uplift rates for this secondary and shallow anticline, varying between 0.02 and 0.1 mm/yr since circa 200 kyr. Trishear forward deformation modeling of the fold indicates that the amplification of the observed fold could be caused by two shallow thrusts formed through a break‐backward activation. This generated a decametric surface fold whose most recent growth was associated with bending‐moment normal faulting in the crestal and forelimb region. Our observations demonstrate that near‐surface compressive tectonics can be caused by blind thrusting, via a complex array of fault and folds: upward strain propagation and generation of shallow low‐angle thrust and related folding seem to be mainly due to secondary fold‐related faulting, according to an out‐of‐syncline thrusting mechanism. Progressive surface deformation induced by blind thrustingCalculated uplift rates constrain the movement of the underlying thrustSecondary fold‐related faults significantly affect fault displacement hazard

Intracellular acid phosphatase activity has been detected in the marine macroalga Ulva rigida. Cytochemical experiments conducted in vegetative cells evidenced the presence of the reaction product adjacent to or along the plasmalemma, within cytoplasmic vesicles and associated with different vacuolar inclusions such as vesicles and multivesicular bodies. This observation leads to infer that acid phosphatases are part of a system through which the orthophosphate anion is obtained from phosphate esters.

Asexual reproduction in Chaetophora elegans occurs through quadriflagellate zoospores. During the process of settlement, zoospores loose the flagella and become rounded. Attachment involves the fixation of zoospores by means of an adhesion disk made up of a mucilage containing neutral polysaccharides. Germlings acquire then a spindle-like shape. Zoospore germination is erect, i.e. the first system formed is the erect one. In an early stage of development, the first unilateral branches are formed, and almost simultaneously, rhizoids are also formed from the spherical basal cell, giving rise to the bipolar stage. The pluricellular prostrate filament develops then from the basal cell. After a month of development, an erect system made up of radially arranged filaments is observed. Zoospores may germinate in groups resulting in a compound thallus. Given that the germination type is related to the final degree of development of the prostrate and erect portions, the study of zoospore germination in the order Chaetophorales is relevant from a taxonomic point of view at generic level.

PROBLEM: Neither the integrin pattern nor the biological functions of integrins have been extensively documented in human cultured testicular peritubular myoid cells (TPMC). The integrin pattern and the presence of some proteins of the immunoglobulin superfamily on human TPMC as well as the role of integrins in TPMC contraction were examined.
 METHOD OF STUDY: Integrin expression was evaluated by immunofluorescence and FACS analysis. To assess the role of integrin in TPMC contraction, human and rat cells were added to a collagen gel system and exposed to contractile stimuli.
 RESULTS: The immunofluorescence and cytofluorimetric analysis showed that human cultured TPMC express α1, α2, α3, α5, α6, αv, β1, β3, and β4 integrin subunits, and significant amounts of intercellular adhesion molecule‐1 (ICAM‐1), whereas they do not present α4, β2, β7 subunits, nor intercellular adhesion molecule‐2 (ICAM‐2) and neural cell adhesion molecule (NCAM). The preincubation of human cells with an anti‐β1 mAb and of rat cells with a polyclonal anti‐β1 antibody inhibited TPMC contraction induced by different contractile stimuli.
 CONCLUSION: Our investigation documented a broad integrin pattern on human cultured TPMC as well as a role for integrins in human and rat TPMC contraction.

The Dead Sea Fault (DSF) is a plate‐boundary where large earthquakes are expected, but there is a lack of such events in the instrumental era. Sequences of earthquakes along the DSF are documented by historical evidence, one of the most devastating occurred in the mid‐eighth century CE. Here we describe site‐specific archaeoseismological observations at the ancient Tiberias city, on the western shore of the Sea of Galilee. We map Roman and Byzantine relics faulted in the mid‐eighth century CE by a pure normal fault. We use geophysical, geomorphological, and structural analyses integrated with published data, to assess the seismic hazard of the Jordan Valley Western Boundary Fault (JVWB). We propose that the normal JVWB can rupture the surface along its ~45 km trace running from Tiberias toward the S crossing Bet Shean, Tel Rehov, and Tel Teomim. The JVWB, parallel to the main strike‐slip Jordan Valley Fault segment, might be regarded as a major earthquake source in this region. We test the hypotheses of both single fault and multifaults rupture scenarios, which result in an expected range of Mw from 6.9 (single rupture of the JVWB) to 7.6 (multiple rupture of the JVWB and Jordan Valley Fault). Our results suggest that seismic source characterization in the Sea of Galilee region must include normal faults capable of surface rupturing, despite the absence of such events in the instrumental catalogue. Surface faulting affected the archeological relics at the ancient Tiberias (Dead Sea Fault, Israel)We attribute this faulting to a mid‐eighth century CE earthquakeOur findings highlight the need for revising the tectonic setting and seismic risk in the Sea of Galilee and nearby regions

Rates of plate motion are generally uniform over 10–102Myrs timescales. Faults between tectonic plates might, therefore, be expected to show temporally‐uniform slip‐rates if the same number of faults remain active. For an extending region of the Eurasia‐Africa plate boundary, Italy, finite throw values (vertical component of the slip) for seismogenic normal faults are less than that predicted when recent throw‐rates are extrapolated over the fault lifetimes. The effect correlates with distance from the fault system tips and demonstrates that the slip‐rates on centrally‐located faults have increased with time. Neighbouring normal faults were active in the Quaternary but show no signs of surface faulting during the latest Pleistocene to Holocene. Death of these faults has provided the extra strain per unit time to drive the increased slip‐rates measured on other faults. Thus, fault interaction and death modify slip‐rates and seismic hazards associated with plate tectonics.