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The Mexican Fold-and-Trust Belt is a winding belt that formed after a series of protracted tectonic events, which began with the onset of sedimentation in the basins formed during the break-up of Pangea and during the roll-back of the oceanic Kula plate in Jurassic times. Later, the continued subduction of Kula-Farallon constituent plates at the western margin of Mexico triggered arc formation, thrusting, basin inversion, and folding. The kinematics of the fold-and-thrust belt curvature at regional and local scales is still debated. Different hypotheses have been explored to explain the trace of the orogen: 1) curvature is mainly and primarily controlled by the basin architecture; 2) Curvature is progressive and was at least partially acquired during deformation being controlled by the basement geometry, lithologic heterogeneities, and/or the shortening direction, and 3) The curvature is, at least partially, postdating the main orogenic deformation structures being formed as the youngest of the deformation phases. Several regional-scale studies have been performed (Eguiluz et al., 2010; Fitz-Diaz et al., 2017). But most of the previous paleomagnetic studies were focused on studying the configuration of the desegregated fragments of Pangea (Molina-Garza et al., 1992). In this study, we investigate the nature of the curvature in the north and central-eastern part of the Mexican Fold and Trust Belt using paleomagnetic data obtained from the Jurassic rocks of the Nazas Formation, this formation is composed of a volcanic and volcano-sedimentary succession of andesites and dacite flows interbedded with tuff deposited in an intra-arc or back-arc setting. Our results show remagnetizations, some potential primary magnetizations, and significant counterclockwise rotations. This implies a potential oroclinal bending origin for at least part of the Mexican fold-and-thrust-belt curvature. This contribution will discuss the potential mechanisms causing the curvature and the implications for the kinematics, tectonic and geodynamic evolution of the central-western Pacific subduction during the Mesozoic-Paleogene in northeastern Mexico. This work is a posthumous contribution of Dr. Roberto Stanley Molina-Garza and a tribute to his huge contribution to the understanding of the tectonic history of Mexico.Keywords: Paleomagnetism; Mexican Fold and Trust Belt; Anticlockwise rotation; Remagnetization; Jurassic; Nazas Arc.

We surveyed a subsurface layer of saturated mobile mud and its microbial fingerprints below the desiccated bottom of a maar lake at Rincón de Parangueo (RP), Mexico. A multi-scale approach was followed using geological fieldwork, coring of the sediments, ground penetrating radar survey, physico-chemical characterization including X-ray diffraction and scanning electron microscope, and high-throughput DNA sequencing methods. The mobile mud is an organic-rich silty clay, with high values of alkalinity, volumetric water content and conductivity. Mud mobility has been attributed to overpressure caused by disequilibrium compaction of sediments related to active subsidence and pore overpressure produced by an input of groundwater and gas content in the sediments and resulted in a diverse set of structures related to mud tectonics such as injection domes and fluid seeps through fractures. Extraction and sequencing of sedimentary environmental DNA in the mud layer were performed for Bacteria and Archaea. Despite the small number of samples obtained, the microbial fingerprint from the sedimentary environmental DNA at subsurface shares similarities with the microbial communities identified on the crater surface. Additionally, we identify the DNA of specific methanogenic microorganisms in the mud, such as Bathyarchaeia, Methanomassiliicoccales, and Methanobacteriales, and we speculate on their probable role in gas production and pore overpressure in the mud layer. The underground mud at Rincón de Parangueo represents a geologically dynamic environment with conditions that are favorable for the thriving of microbial communities.

Plants exhibiting the water-conserving crassulacean acid metabolism (CAM) photosynthetic pathway provide some of the most intriguing examples of photosynthetic diversity and plasticity. Here, a largely unnoticed facet of CAM-plant photosynthesis is highlighted: the co-occurrence of ontogenetically controlled constitutive and environmentally controlled facultative CAM in a species. Both forms of CAM are displayed in leaves of Coleus amboinicus Lour. (Lamiaceae), a semi-succulent perennial plant with oregano-like flavour that is native to southern and eastern Africa and naturalised elsewhere in the tropics. Under well-watered conditions, leaves assimilate CO2 predominantly by the C3 pathway. They also display low levels of CO2 uptake at night accompanied by small nocturnal increases in leaf tissue acidity. This indicates the presence of weakly expressed constitutive CAM. CAM expression is strongly enhanced in response to drought stress. The drought-enhanced component of CAM is reversible upon rewatering and thus considered to be facultative. In contrast to C. amboinicus, the thin-leaved closely related Coleus scutellarioides (L.) Benth. exhibits net CO2 fixation solely in the light via the C3 pathway, both under well-watered and drought conditions. However, low levels of nocturnal acidification detected in leaves and stems indicate that the CAM cycle is present. The highly speciose mint family, which contains few known CAM-exhibiting species and is composed predominantly of C3 species, appears to be an excellent group of plants for studying the evolutionary origins of CAM and for determining the position of facultative CAM along the C3–full CAM trajectory.

In this work, we quantify the differential subsidence that occurred between 2015 and 2016 in a maar-lake that has been desiccating due to the large groundwater extraction rates of the aquifer that ...

SummarySucculence is found across the world as an adaptation to water-limited niches. The fleshy organs of succulent plants develop via enlarged photosynthetic chlorenchyma and/or achlorophyllous water storage hydrenchyma cells. The precise mechanism by which anatomical traits contribute to drought tolerance is unclear, as the effect of succulence is multifaceted. Large cells are believed to provide space for nocturnal storage of malic acid fixed by crassulacean acid metabolism (CAM), whilst also buffering water potentials by elevating hydraulic capacitance (CFT). Furthermore, the effect of CAM and elevated CFT on growth and water conservation have not been compared, despite the assumption that these adaptations often occur together.We assessed the relationship between succulent anatomical adaptations, CAM and CFT, across the genus Clusia. In addition, we simulated the effects of CAM and CFT on growth and water conservation during drought using the Photo3 model.Within Clusia leaves, CAM and CFT are independent traits: CAM requires large palisade chlorenchyma cells, whereas hydrenchyma tissue governs interspecific differences in CFT. In addition, our model suggests that CAM supersedes CFT as a means to maximise CO2 assimilation and minimise transpiration during drought.Our study challenges the assumption that CAM and CFT are mutually dependent traits within succulent leaves.

This article explores the concept of science diplomacy as a specific vector of foreign policy, its historical evolution, and its relevance in the present context for both the scientific and diplomatic communities, which have different but not necessarily diverging interests. By analysing the history of science diplomacy and its conceptual framework (including in light of some of the most relevant theories of International Relations, such as Realism, Liberalism, and Constructivism), it attempts to demonstrate how science constitutes not only one of the subjects of diplomacy, but also one of its actors; not only one of its ends but also one of its means. In the process of identifying those agents, goals, and tools as defining elements of science diplomacy as an autonomous field on its own, both in terms of theory and practice, this article interrelates the concept of science diplomacy with other current forms of external action, such as economic diplomacy, public diplomacy, people-to-people diplomacy, or cultural diplomacy.

In this paper we report U Pb zircon ages from a syn-tectonic magmatism related to a contractional thick-skinned deformation pulse in the Mexican Fold and Thrust Belt. The study area corresponds to the Concepcion del Oro Block (COB), which is located in northern Zacatecas, Mexico. The COB is a NW-SE trending elongated tectonic structure located south of the Parras Transversal Sector in the Mexican Fold Thrust Belt (MFTB) in north-central Mexico. In this area, regional thin-skinned folds were formed between the late Turonian and Campanian and they define the core of a major northeastward-convex orocline around Concepcion del Oro mining district, Zacatecas, Mexico. The regional folds were cut by four Eocene-early Oligocene plutons (43-32 Ma; U Pb zircon), which in places modified the older thin-skinned structures. Magma was emplaced along thrust faults and modified the attitude of inverted limbs of overturned folds, and the orientation or position of the fold axis at the core of anticlines, causing the formation of complex emplacement-related deformation. Two NW-SE trending lineaments bound the COB, and both cut the periclinal ends of the thin-skinned older folds, at different time. The eastern lineament is here interpreted as a high angle reverse fault, which tilted polymictic conglomeratic continental succession that includes cobbles derived from one of the intrusive bodies and an andesitic syn-tectonic lava flow (40.7 ± 0.6 Ma; U Pb zircon). The western lineament is a normal fault generated by later regional tectonic extension related to the Basin and Range province. Altogether suggests that a late Eocene-early Oligocene contractional thick-skinned deformation pulse affected the COB. This pulse was contemporaneous with the Eocene-Oligocene magmatism in the Concepcion del Oro, Zacatecas region, and is similar in style and age to some of the structures produced by the Laramide orogeny in the southern Rocky Mountains and in some isolated areas in northern Mexico.

Cellular therapies are creating a paradigm shift in the biomanufacturing industry. Particularly for autologous therapies, small-scale processing methods are better suited than the large-scale approaches that are traditionally employed in the industry. Current small-scale methods for manufacturing personalized cell therapies, however, are labour-intensive and involve a number of 'open events'. To overcome these challenges, new cell manufacturing platforms following a GMP-in-a-box concept have recently come on the market (GMP: Good Manufacturing Practice). These are closed automated systems with built-in pumps for fluid handling and sensors for in-process monitoring. At a much smaller scale, microfluidic devices exhibit many of the same features as current GMP-in-a-box systems. They are closed systems, fluids can be processed and manipulated, and sensors integrated for real-time detection of process variables. Fabricated from polymers, they can be made disposable, i.e. single-use. Furthermore, microfluidics offers exquisite spatiotemporal control over the cellular microenvironment, promising both reproducibility and control of outcomes. In this chapter, we consider the challenges in cell manufacturing, highlight recent advances of microfluidic devices for each of the main process steps, and summarize our findings on the current state of the art. As microfluidic cell culture devices have been reported for both adherent and suspension cell cultures, we report on devices for the key process steps, or unit operations, of both stem cell therapies and cell-based immunotherapies.

Exceeding thermal thresholds causes irreversible damage and ultimately loss of leaves. The lowland tropics are among the warmest forested biomes, but little is known about heat tolerance of tropical forest plants. We surveyed leaf heat tolerance of sun-exposed leaves from 147 tropical lowland and pre-montane forest species by determining the temperatures at which potential photosystem II efficiency based on chlorophyll a fluorescence started to decrease (TCrit ) and had decreased by 50% (T50 ). TCrit averaged 46.7°C (5th-95th percentile: 43.5°C-49.7°C) and T50 averaged 49.9°C (47.8°C-52.5°C). Heat tolerance partially adjusted to site temperature; TCrit and T50 decreased with elevation by 0.40°C and 0.26°C per 100 m, respectively, while mean annual temperature decreased by 0.63°C per 100 m. The phylogenetic signal in heat tolerance was weak, suggesting that heat tolerance is more strongly controlled by environment than by evolutionary legacies. TCrit increased with the estimated thermal time constant of the leaves, indicating that species with thermally buffered leaves maintain higher heat tolerance. Among lowland species, T50 increased with leaf mass per area, suggesting that in species with structurally more costly leaves the risk of leaf loss during hot spells is reduced. These results provide insight in variation in heat tolerance at local and regional scales.

Plants exhibiting the water-conserving crassulacean acid metabolism (CAM) photosynthetic pathway provide some of the most intriguing examples of photosynthetic diversity and plasticity. Here, a largely unnoticed facet of CAM-plant photosynthesis is highlighted: the co-occurrence of ontogenetically controlled constitutive and environmentally controlled facultative CAM in a species. Both forms of CAM are displayed in leaves of Coleus amboinicus Lour. (Lamiaceae), a semi-succulent perennial plant with oregano-like flavour that is native to southern and eastern Africa and naturalised elsewhere in the tropics. Under well-watered conditions, leaves assimilate CO2 predominantly by the C3 pathway. They also display low levels of CO2 uptake at night accompanied by small nocturnal increases in leaf tissue acidity. This indicates the presence of weakly expressed constitutive CAM. CAM expression is strongly enhanced in response to drought stress. The drought-enhanced component of CAM is reversible upon rewatering and thus considered to be facultative. In contrast to C. amboinicus, the thin-leaved closely related Coleus scutellarioides (L.) Benth. exhibits net CO2 fixation solely in the light via the C3 pathway, both under well-watered and drought conditions. However, low levels of nocturnal acidification detected in leaves and stems indicate that the CAM cycle is present. The highly speciose mint family, which contains few known CAM-exhibiting species and is composed predominantly of C3 species, appears to be an excellent group of plants for studying the evolutionary origins of CAM and for determining the position of facultative CAM along the C3-full CAM trajectory.

Mononuclear phagocytes (MNPs) are present in neovascular age-related macular degeneration (nv AMD) which is also called choroidal neovascularization (CNV). The number and phenotype of the MNPs depend upon the local environment in the CNV and effect of nv AMD therapy. We investigated ocular cell infiltration and conditions that modulate angiogenesis in a laser-induced mouse CNV model.We developed assays to quantify MNPs in our established mouse CNV model. One MNP assay quantified the number of subretinal cells peripheral to the CNV lesions. A second assay semiquantitatively assesses the number of MNPs localized to the CNV lesion. We used these assays to measure the effect of toll-like receptor-2 (TLR-2) activation, anti-vascular endothelial growth factor (VEGF) therapy, and chemokine (C-C motif) ligand 2 (Ccl2) genetic deletion on MNP infiltration after laser injury.Laser injury induced blood vessel growth and infiltration of MNPs. Systemic administration of a TLR-2 activating peptide increased laser-induced CNV area, MNP cell numbers, and MNP density over the CNV lesions. Systemic administration of a VEGF antibody reduced CNV area, while Ccl2 genetic deletion increased CNV area. Despite the change in amount of angiogenesis, MNP infiltration was, surprisingly, unchanged in these 2 conditions.MNP quantification provides biological insights for candidate AMD therapies. The number of infiltrating MNP cells does not correlate with the amount of laser-induced CNV area.

This work describes the distribution, macro and microstructures of modern microbialites deposited in the marginal facies of a Quaternary paleo-lake at Rincon de Parangueo, within the central trans-mexican volcanic belt. This paleo-lake formed after the volcanic eruption and maar formation that provided suitable conditions at its margins for substrate colonization and microbial proliferation. Vesicular thrombolites, grouped into domical and irregular clusters, were mapped, measured and analyzed. These microbialites are characterized by a 2 cm-thick stromatolitic crust and a thrombolitic matrix that accreted by carbonate precipitation. The stromatolitic crusts represent the last accretion stages at intertidal conditions before the complete evaporation of the paleo-lake. The asymmetrical distribution and preservation of these microbial deposits suggest that the rapid subsidence and tectonic deformation began before the lake completely dried out. The maar at Rincon de Parangeo represents not only an important record of recent geological processes in dynamic interaction with microbial processes under increasingly extreme alkaline conditions (pH between 10 and 10.6), but also a possible analogue for some Precambrian sequences. It provides an example of a rapidly transforming environment where macro and micro geobiological interactions directly influence biological succession.

Clusia guabalensis (Clusiaceae), a new species from wet forests on the Atlantic slope in northern Panama is described. Phylogenetic relationships and morphological affinities of this new species to other taxa in Clusia are discussed.

The recent discovery of a fossil of Enhydritherium terraenovae in upper Miocene fluvial deposits in Juchipila (Mexico), nearly 200 km away from the nearest coast, together with other known occurrences of the same species in Florida and California, made possible to envision an alternative to the Panamanian and Polar routes of migration through fluvial systems in Mexico. In order to cross from one ocean to the other, individuals of E. terraenovae must have passed the continental divide, which is a physiographic feature that separates surface waters that flow into the Atlantic and Pacific versants. Two vast endorheic regions, which together span more than 400,000 km2 in area, currently dominate drainage systems in northern and central Mexico. The endorheic regions are broadly bounded by two mountain ranges and coincide with the arid and semi-arid regions of the Chihuahuan desert. These closed basins are an additional obstacle for migration. However, drainage systems are constantly varying and adjusting to changing conditions imposed by climate, tectonic activity, volcanism, and pronounced asymmetries in topography and rainfall distribution. The migration route across Mexico for Enhydritherium terraenovae in the late Miocene (≥6 Ma) could have been facilitated by one or more river captures that inverted the flow direction near the headwaters of a drainage system that debouched either into the Gulf of Mexico or the Pacific coast. Biologists studying fresh water fish faunas in the southern part of the United States and in northern and central Mexico have documented several living species that occur in both the Rio Grande and in the Mezquital rivers, two drainages that are not presently connected, drain in opposite directions (i.e. towards the Gulf of Mexico and the Gulf of California, respectively) and are separated by the endorheic regions. Furthermore, systematic studies of fresh water fish faunas in the region has numerous examples of endemicity and allopatric speciations that are interpreted as evidence of several events of drainage system rearrangement either by stream capture, beheading, or river diversion or by fragmentation caused by formation of closed basins by faulting, volcanic activity or isostatic rebound in the footwall block of normal faults. The western boundaries of the extensive endorheic regions in Mexico are controlled mainly by a highland produced by intense felsic volcanism during the Sierra Madre Occidental activity (Eocene – Miocene), and the eastern hydrological divide coincides with mountains associated with the fold and thrust belt produced by the Hidalgoan orogeny in early Cenozoic time. Normal faulting associated with Basin and Range extension formed additional closed basins. Another major factor in the formation of the endorheic regions is the terminal Miocene climate change, which caused runoff reduction and lowered the rivers capacity of erosion. Opening of the Gulf of California changed the overall slope of rivers draining into the Pacific in northwestern Mexico triggering the capture of rivers formerly confined to the closed basins or draining to the Gulf of Mexico. Quaternary normal faults have been documented a few tens of kilometers from the hydrological divides of the endorheic regions, suggesting that in some regions there is an active tectonic component in their formation. The location of the crossing point for the otters is uncertain as the fossil record is scant and investigation on the evolution of drainage systems through time in Mexico is in the early stages. However, it is argued that there is a fair chance that the crossing occurred via the Mezquital river capture near Durango city. Isotopic age of the sediments where the Enhydritherium terraenovae fossil was collected, imply that the capture must have occurred in the late Miocene.