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Financiado para publicación en acceso aberto: Universidade da Coruña/CISUG [Abstract] Understanding the environmental response to the last glacial termination in regions located in transitional climate zones such as the Atlantic Iberian mountains is crucial to estimate potential changes in regions affected by current glacial melting. We present an 8.5 m-long, solid last deglaciation and Holocene chronostratigraphic record including detailed sediment analysis from Lake Peixão, a pro-glacial lake in the Serra da Estrela (Central Portugal). The age–depth model relies on a Bayesian approach that includes 16 AMS 14C dates and 210Pb–137CS measurements, robustly dating the lake formation at 14.7 ± 0.32 cal. ka BP. This chronological reconstruction shows an average sedimentation rate of ca. 0.07 cm yr−1 (15 yr cm−1), enabling proxy analyses at decadal timescales. The sediment sequence is composed of five lithological units: (U1) coarse and unsorted fluvioglacial lacustrine deposits; (U2) massive fluvioglacial lacustrine deposits (863–790 cm below surface [bsf]; 14.7 ± 0.32–13.8 ± 0.12 cal. ka BP); (U3) water current fluvioglacial lacustrine deposits (790–766 cm bsf; 13.8 ± 0.12–12.9 ± 0.29 cal. ka BP); (U4) laminated/banded lacustrine deposits characterized by terrigenous deposits from ice-covered lake periods and episodic events of ice and snow melting (766–752 cm bsf; 12.9 ± 0.29–11.7 ± 0.15 cal. ka BP); and (U5) massive muddy lacustrine deposits (752–0 cm bsf; 11.7 ± 0.15 cal. ka BP–present). The occurrence of U2 to U4 deposits defines the transition from glacial cold (U1) to net warm postglacial conditions (U5). These climate transitions are marked by changes in sediments and the presence of very low sedimentation rate periods, possibly related to the Intra-Allerød Cold Period and the coldest phase of the Younger Dryas. Our results support the previously proposed timing of the retreat of the Serra da Estrela glaciers ca. 13.8 ± 0.12 cal. ka BP. The robust chronology of Lake Peixão highlights the potential of Iberian pro-glacial lakes for dating deglaciation processes and will lead to unprecedented decadal-to-centennial timescale palaeoclimate reconstructions in this region since the last glacial–interglacial transition. This work was supported by the Portuguese Foundation for Science and Technology – FCT, through the HOLMODRIVE project (PTDC/CTA-GEO/29029/2017). A. Hernandez is funded by the Spanish Ministry of Science and Innovation through the Ramón y Cajal Scheme [RYC2020-029253-I]. C. Martin-Puertas is funded by UKRI-FLF MR/W009641/1. G. Gil-Romera is funded by the DFG project FOR2358 ‘The Mountain Exile Hypothesis’. Pedro M. Raposeiro was funded by the Portuguese Science Foundation through contract DL57/2016/ICETA/EEC2018/25. Alexandre M. Ramos is funded by the Helmholtz ‘Changing Earth’ programme. Funding for open access charge: Universidade da Coruña/CISUG. The Estrela UNESCO Global Geopark is thanked for their support with field activities and permissions. The Parque Natural da Serra da Estrela (ICNF) provided research permits. Deutsche Forschungsgemeinschaft; FOR2358 Portugal. Fundação para a Ciência e a Tecnologia; DL57/2016/ICETA/EEC2018/25 Portugal. Fundação para a Ciência e a Tecnologia; PTDC/CTA-GEO/29029/2017 UK Research and Innovation; UKRI-FLF MR/W009641/1

Caesarean section is one of the most common surgeries worldwide, even though there is no evidence supporting maternal and perinatal long-term benefits. Furthermore, the mechanical behavior of a caesarean scar during a vaginal birth after caesarean (VBAC) is not well understood since there are several questions regarding the uterine wound healing process. The aim of this study is to investigate the biomechanical Maylard fiber reorientation and stiffness influence during a VBAC through computational methods. A biomechanical model comprising a fetus and a uterus was developed, and a chemical-mechanical constitutive model that triggers uterine contractions was used, where some of the parameters were adjusted to account for the matrix and fiber stiffness increase in the caesarean scar. Several mechanical simulations were performed to analyze different scar fibers arrangements, considering different values for the respective matrix and fibers stiffness. The results revealed that a random fiber arrangement in the Maylard scar has a much higher impact on its mechanical behavior during a VBAC than the common fibers arrangement present in the uninjured uterine tissue. An increase of the matrix scar stiffness exhibits a lower impact, while an increase of the fiber's stiffness has no significant influence.

The Serra da Estrela range in Central Portugal is a key region to explore the Last Glacial termination in the Atlantic region of Iberia. We present the Late Glacial and Holocene record of Lake Peixão to reconstruct past environmental and climatic conditions at decadal timescales. We retrieved an 8.5m long core in the central and deepest zone of the lake. From the base to the top, the sediment core is composed of i) a thick layer (aprox. 0.5 m) of gravel-to-sand quartz clasts; ii) an alternation of one meter thick grey to pale-brown sandy deposits; and iii) homogeneous dark brown and pale-brown organic-rich muddy facies (ca. 7 meters). Using a Bayesian statistical model based on 16 radiocarbon dates using pollen concentrated samples and 210Pb measurements, we have developed an age-depth model covering the last ca. 14.6 ka, recording the onset of the lake at that time. Lake and mire records previously published in the area generally support this chronology for the formation of proglacial lakes. In addition, the proposed timing for the disappearance of the Serra da Estrela glaciers has been based on Cosmic-Ray Exposure dating (in situ cosmogenic 36Cl) of exposed moraine boulders and glacially polished bedrock surfaces. These results indicate that the end of the glacier’s presence in Serra da Estrela occurred at ca. 14.2 ka BP (during the Bølling-Allerød Interstadial). Therefore our results broadly suport the timing of the end of the deglaciation at the Serra da Estrela and highlight the value of lake sedimentary records. Moreover, the availability of last termination and Holocene highly-resolved sediments from Lake Peixão is likely to record very valuable evidence of climatic and environmental changes at decadal timescales extending from the last deglaciation, through the Holocene. This new multi-proxy data of the Lake Peixão sedimentary sequence will enable comparisons to other decadal-resolved records and support further investigations from the Mediterranean Iberian region.The financial support for this work was possible through the following FCT project: HOLMODRIVE—North Atlantic Atmospheric Patterns Influence on Western Iberia Climate: From the Late Glacial to the Present (PTDC/CTA-GEO/29029/2017).

Interglacials older than 450,000 years ago (ka) are still poorly documented at regional and global scale limiting our knowledge of the wide range of their potential variability and the understanding of the causes of such diversity. Here we present δ18O benthic foraminifera measurements along with sea surface temperature reconstructions and pollen data from IODP site U1385, collected during Expedition 339 « Mediterranean Outflow » on the southwestern Iberian margin, for the Early-Middle Pleistocene interglacials MIS 19, 17, 15 and 13 (~800 to 400 ka). The recorded vegetation and climate changes on land have been directly compared with changes in the eastern North Atlantic subtropical gyre and the global ice volume. This comparison reveals a different structure in the evolution of the Mediterranean forest during these interglacials. The highest forest development occurred during MIS 19e and 15e but in the middle part of MIS 13 (MIS 13c). In contrast with MIS 19, 15 and 13 marked by three more or less similar Mediterranean forest expansions, MIS 17 was characterised by one strong expansion in its middle part (MIS 17c), the strongest of the last 800,000 years, occurring just before the end of the Middle Pleistocene Transition, i.e. the establishment of the strong 100-kyr glacial cycles at ~700 ka. The duration of the first forested phase was also variable depending on the interglacial with a length of ~12,000 years during MIS 19e and 15e, ~9,000 years for MIS 13c and as long as 16,000 years for MIS 17c. Interestingly, two Mediterranean forest expansions are recorded during two phases of ice growth, MIS 19b and 15b, indicating once more the decoupling between the evolution of global ice volume and the southern European environments. The comparison of the U1385 pollen record, located below 40°N, with sequences above 40°N, for example the Lake Orhid pollen record, shows that the structure and magnitude of the interglacials are different below and above this latitude. At Montalbano Jonico, southern Italy at 40°N, the forest expansion is also very strong (80%) during MIS 17 contrasting with the limited development in Lake Orhid. At this site, MIS 19 is further marked by a strong forest development contrasting with the limited expansion of the Mediterranean forest in SW Iberia.

The compound-specific signal of leaf wax n-alkanes can be used for reconstructing climatic and environmental changes. This work assesses the carbon and hydrogen isotopic compositions of sedimentary n-alkanes from a high-mountain lake record (Lake Peixão) in Serra da Estrela (Western Iberia, Portugal) over the last 2000 years.Our interpretations are supported by the modern settings of the lake and the long-chain n-alkanes characterization of the modern vegetation in the lake’s watershed. The δ13C signal of long-chain n-alkanes (C29 – C33) suggests that terrestrial vegetation, dominated by C3 heathlands and grass mosaics, did not change significantly since the last 2000 years. In contrast, δ13C signatures of C25 and C27, associated with aquatic plants inputs, reveal a more enriched and variable signal, suggesting these compounds as indicators of water availability in the studied area. In this high-altitude setting, temperature significantly controls water availability and the δD signal of terrestrial plants (δDterr), which shows major changes across the last 2000 years. In contrast, aquatic-derived n-alkanes (δDaq) show a relatively constant and stable water source. These data enabled us to detect major climate shifts in the region and evaluate the role of the main drivers (solar activity and the North Atlantic Oscillation-NAO) in those long-term changes prior to intense human activities.The Roman Period (0 – 500 AD) was relatively dry but shifting from a warm to a cold phase, under a predominant positive mode of NAO and a Grand solar maxima. From the Dark Ages until the Medieval Climatic Anomaly (500 – 1300 AD), the climate was generally mild and wet under a nonstationary mode of NAO and a gradual decrease in solar irradiance. The LIA (ca. 1350 – 1850 AD) was composed by two main phases: the first cold and wet followed by an extreme cold episode; both under a predominantly negative NAO mode. The extreme cooling (centered at 1700 AD), coincident with the Maunder Minimum, was driven by the southward displacement of the polar front, causing extended periods of ice cover on the lake. The climate became warm and dry since 1880 AD, coinciding decrease in vegetation capability to buffer the runoff energy and promote the observed high sedimentation rate during this period, probably due to increased anthropogenic impact. This work also underlines the sensitive nature of the high-mountain lake ecosystems and contributes to the spatial coverage of paleoclimate studies in the Atlantic region of the Iberian Peninsula.AcknowledgmentsThe authors are grateful to FCT (Fundação para a Ciência e a Tecnologia) for the financial support of this work through the projects: HOLMODRIVE—North Atlantic Atmospheric Patterns Influence on Western Iberia Climate: From the Late Glacial to the Present (PTDC/CTA-GEO/29029/2017). WarmWorld—Features, and lessons from Past Interglacials “warm periods” during the last 1.5 Ma (PTDC/CTA-GEO/29897/2017). RNS´s grant supported by Ultimatum—Understanding past climatic instabilities in the North Atlantic Region (IF/01489/2015)

Regular intestinal motility is essential to guarantee complete digestive function. The coordinative action and integrity of the smooth muscle layers in the small intestine's wall are critical for mixing and propelling the luminal content. However, some patients present gastrointestinal limitations which may negatively impact the normal motility of the intestine. These patients have altered mechanical and muscle properties that likely impact chyme propulsion and may pose a daily scenario for long-term complications. To better understand how mechanics affect chyme propulsion, the propulsive capability of the small intestine was examined during a peristaltic wave along the distal direction of the tract. It was assumed that such a wave works as an activation signal, inducing peristaltic contractions in a transversely isotropic hyperelastic model. In this work, the effect on the propulsion mechanics, from an impairment on the muscle contractile ability, typical from patients with systemic sclerosis, and the presence of sores resultant from ulcers was evaluated. The passive properties of the constitutive model were obtained from uniaxial tensile tests from a porcine small intestine, along with both longitudinal and circumferential directions. Our experiments show decreased stiffness in the circumferential direction. Our simulations show decreased propulsion forces in patients in systemic sclerosis and ulcer patients. As these patients may likely need medical intervention, establishing action concerning the impaired propulsion can help to ease the evaluation and treatment of future complications.

Nowadays, primary productivity variations at the SW Iberian Margin (IbM) are primarily controlled by wind-driven upwelling. Thus, major changes in atmospheric circulation and wind regimes between the Marine Isotope Stages (MIS) 12 and 9 could have driven substantial changes in phytoplankton productivity which remains poorly understood. We present a high-resolution calcareous nannofossil record from the Shackleton Site Integrated Ocean Discovery Program Site U1385 that allow the assessment of primary productivity and changing surface conditions on orbital and suborbital timescales over the SW IbM. These records are directly compared and integrated with terrestrial – Mediterranean forest pollen – and marine – benthic and planktic oxygen stable isotopes (δ18O), alkenone concentration [C37], Uk´37-Sea Surface Temperature and % C37:4 – proxy records from Site U1385. Our results indicate intra-interglacial increase in primary productivity together with intensification of the Azores anticyclonic high-pressure cell beyond the summer that suggests a two-phase upwelling behavior during the full interglacial MIS 11c (420–397ka), potentially drived by atmospheric NAO-like variability. Primary productivity is largely enhanced during the inception of glacial MIS 10 and the early MIS 10 (392–356ka), linked to intensified upwelling and associated processes during a period of strengthened atmospheric circulation. In agreement with the conditions observed during Heinrich events of the last glacial cycle, primary productivity reductions during abrupt cold episodes, including the Heinrich-type (Ht) events 4 to 1 (436, 392, 384 and 339ka) and the Terminations V and IV, seems to be the result of halocline formation induced by meltwater arrival, reducing the regional upward nutrient transference FPU17/03349, PTDC/CTA-GEO/29897/2017, UIDB/04326/2020, UIDB/04326/2020, CEECIND/02208/2017 info:eu-repo/semantics/publishedVersion

Located between the temperate and arid climates of Europe and North Africa, Iberia is one of the most climatic vulnerable regions of Europe with more severe and longstanding extreme climate events being expected in this region. The Iberian climate, mainly in winter, is modulated by the North Atlantic Oscillation (NAO). Persistent positive (negative) NAO phases, can lead to significant changes in the North Atlantic westerly wind-belts, resulting in strengthened (weakened) winter precipitation in Western Iberia.The Iberian Central System mountain range constitutes one of the biggest physical barriers to the moist air masses coming from the Atlantic Ocean. Usually, under low anthropic influence, the high mountain lake ecosystems have sensitive responses to climate and environmental changes, which makes lake sediments a pristine record for paleo reconstructions.The increasing number of studies on Iberian high lakes depicted a wide spectrum of spatiotemporal variability in climate and environmental conditions for the last few millennia. However, the paucity of archives from the western region hampers the understanding of the effect of major climate forcings on different climate periods.In this sense, to assess the past hydroclimatic patterns over western Iberia, we study upper 120 cm sediments of a 5 m core retrieved from a high mountain lake in central Portugal (Lake Peixão, Serra da Estrela). The age and depth model provides a robust chronology of the last 3600 years based on four 14C AMS dating on pollen concentrates and 137Cs and 210Pb profiles.Here we present the preliminary results on sedimentary lipid biomarker (leaf wax n-alkane) and compound-specific hydrogen isotope (δDwax) analysis performed at centennial time scale resolution. n-Alkane characterization, based on diverse indices (e.g., ACL, CPI, Paq, relative percentages, etc.), shows a clear higher plant signal, with a strong odd-over-even carbon predominance of long-chain n-alkanes, and predominance of the C31 homologue. Principal component analysis (PCA) applied to the odd n-alkanes (C17 – C35) concentrations reduced the data dimensionality into two principal components (PC). The PC1 mostly represents total n-alkane concentrations. PC2 has a positive correlation with Paq, C27, and δD signals, while a high negative correlation with ACL. Another important feature of the PC2 signal is its parallelism with NAO index reconstructions.Our new data show a sensitive response from the lake catchment vegetation to hydroclimatic variability and allow the reconstruction of climatic phases occurring in this region based on plant waxes from Lake Peixão.AcknowledgmentsThe financial support for this work was possible through the following FCT project: HOLMODRIVE—North Atlantic Atmospheric Patterns Influence on Western Iberia Climate: From the Late Glacial to the Present (PTDC/CTA-GEO/29029/2017).

Marine Isotope Stage (MIS) 13, ~500 ky ago, represents a Quaternary interglacial of primary interest due to the unexpected enhancement of monsoon systems under a cool climate characterised by low atmospheric CO2 and larger ice volume than the present interglacial. Yet, key questions remain about its regional expression (intensity, climate variability, length) and underlying forcing factors. Here we examine the SW Iberian vegetation and terrestrial climate during MIS 13 directly compared with the sea surface temperatures using sediments from IODP Site U1385, and combine those terrestrial-marine profiles with climate-model experiments. We show for the first time that MIS 13 stands out for its large forest expansions with a reduced Mediterranean character alternating with muted forest contractions, indicating that this stage is marked by a cool-temperate climate regime with high levels of humidity. Results of our data-model approach reveal that that the dominant effect of MIS 13 insolation forcing on the regional vegetation and precipitation regime in SW Iberia is amplified by the relatively large extent of the ice-sheets in high northern latitudes. In qualitative agreement with the pollen-based evidence, model results show that ice-sheet forcing triggers an increase in the SW Iberian tree fraction along with both intensified winter and summer rainfall. We propose that the interactions between ice-sheets and major atmospheric circulation systems may have resulted in the persistent influence of the mid-latitude cells over the SW Iberian region, which led to intensified moisture availability and reduced seasonality, and, in turn, to a pronounced expansion of the temperate forest.

During vaginal delivery, the fetal head molds into an elongated shape to adapt to the birth canal, a process known as fetal head molding. However, excessive molding can occur due to prolonged labor or strong contractions, leading to several disorders on the fetal head. This work aims to perform a numerical study on the biomechanics of fetal head molding by measuring specific diameters and the corresponding molding index. A finite element model of the pelvic floor muscles and the fetal body was used. The fetal head is composed of the skin and soft tissues, the skull with sutures and fontanelles, and the brain. The sutures and fontanelles were modeled with membrane elements and characterized by a visco-hyperelastic constitutive model adapted to a plane stress state. Simulations were performed to replicate the second stage of labor in the vertex presentation and occipito-anterior position. With the introduction of viscoelasticity to assess a time-dependent response, a prolonged second stage of labor resulted in higher molding. The pressure exerted by the birth canal and surrounding structures, along with the presence of the pelvic floor muscles, led to a percentage of molding of 9.1%. Regarding the pelvic floor muscles, a 19.4% reduction on the reaction forces and a decrease of 2.58% in muscle stretching was reported, which indicates that sufficient molding may lead to fewer injuries. The present study demonstrates the importance of focusing on the fetus injuries with non-invasive methods that can allow to anticipate complications during labor.

Background and objective During vaginal delivery, several positions can be adopted by the mother to be more comfortable and to help the labor process. The positions chosen are very influenced by factors such as monitoring and intervention during the second stage of labor. However, there is limited evidence to support the most ideal birthing position. This work aims at contributing to a better knowledge associated with the widening of the pubic symphysis and the biomechanics of flexible and non-flexible sacrum positions that can be adopted during the second stage of labor, as well as their resulting pathophysiological consequences. Methods A validated computational model composed by the pelvic floor muscles attached to the bones, and a fetus head was used to simulate vaginal deliveries. This model was modified to mimic two birthing positions: one that allows the free movement of the coccyx as in flexible sacrum positions and other in which this movement is more restricted as in non-flexible sacrum positions. The widening of the pubic symphysis was also considered to facilitate the passage of the fetus head. Results The results obtained showed that, in non-flexible sacrum positions, where the coccyx movement is restricted, occur a rotation of 3.6° of the coccyx and a widening of 6 mm of the pubic symphysis. In contrast, in flexible sacrum positions, where the coccyx is free to move, occur a rotation of 15.7° of the coccyx and a widening of the pubic symphysis of 3 mm, appearing to be more beneficial for the mother's pelvis, but slightly higher stresses were detected in the pelvic floor muscles. Conclusions Globally, the results obtained allow to conclude that different birthing positions lead to changes in the female pelvic space, so certain positions can be adopted by the mother during the second stage of labor to reduce the risk of obstructed labor and the development of several dysfunctions. More specifically, flexible sacrum positions, such as kneeling, standing, squatting and sitting positions, are more beneficial for the bone structure of her pelvis as they allow a higher coccyx movement and lower widening of the pubic symphysis.

Understanding past variability and forcing mechanisms of the Asian monsoon system is of key importance for better forecasting its behaviour under future global warming scenarios and how this may affect modern societies and economies. So far, knowledge about long-term monsoon variability in mainland Asia is mainly based on proxy records from Chinese speleothems, primarily recording changes of the East Asian Summer Monsoon (EASM). These records have provided evidence for orbital-scale monsoon variability, driven by Northern Hemisphere summer insolation changes, but also for centennial- to millennial-scale reductions in monsoon precipitation. These so-called Weak Monsoon Intervals (WMIs) occurred synchronously to cold intervals in the North Atlantic realm, e.g. during Heinrich Events, pointing at a close hemisphere-scale climatic teleconnection between the North Atlantic and Asia. However, the exact mechanisms that control short-term monsoon variability are still elusive. Moreover, long-term palaeomonsoon proxy records from the core zone of the Indian Summer Monsoon (ISM) are still relatively scarce compared to those from the EASM realm. To identify possible short-term changes in ISM intensity and reconstruct related hydroclimate and vegetation changes on the Indian subcontinent during the interval ~6–74 ka BP, sediments from IODP Site U1446 in the NW Bay of Bengal have been analysed. This site, being located within the reach of the Mahanadi River, is characterized by high riverine input of terrestrial organic matter and thus ideal for high-resolution analyses of pollen content and the stable hydrogen (δD) and carbon (δ13C) isotope composition of n-alkanes from terrestrial plant leaf waxes. Here we present preliminary results of δD and δ13C analyses on odd-numbered long-chain n-alkanes (n-C27 to n-C33,) extracted from the IODP Site U1446 sediments. These indicate several reductions in ISM precipitation during the last glacial, which occurred parallel to cold events in the North Atlantic realm, e.g. during Heinrich events H1, H2, H4, H5 and H6. In combination with pollen and alkenone-based (UK’37) sea surface temperature data from the same sediments, we aim at (1) providing a comprehensive and high-resolution reconstruction of past ISM variability and associated vegetation changes on the Indian subcontinent and (2) understanding the trigger mechanisms of centennial- to millennial-scale WMIs, particularly in relation to changes in Indian Ocean oceanography.

Anthropogenic CO2 release into the atmosphere leads to temperature projections for 2100 only experienced on Earth since many million years. However, those periods are poorly known due to low temporal and spatial data and ill-defined climate forcings. However past warm periods (interglacials), occurring during the Quaternary, under variable boundary conditions (e.g. greenhouse gases concentration, sea level and ice sheets size, insolation and orbital forcing), can provide invaluable information on the dynamics and processes behind natural warm climates. Here we present records for the sea surface temperature based in Uk’37-SST at orbital and millennial-scale over the last 1.25 Ma, with special focus on the past interglacials of two SW Iberian margin sedimentary sequences recovered during IODP Expedition 339, Sites U1385 (37°34.285′N, 10°7.562′W; 2589m) and U1391 (37°21.5322′N, 9°24.6558′W; 991m). We also performed a data-model comparison to explore the dynamics related with the role of obliquity on the Atlantic Meridional Overturning Circulation (AMOC) changes. Our data show that Interglacials are characterized by an interval of maximum warmth followed by a temperature decline punctuated by millennial-scale SST oscillations. In most cases the first stadial marks the beginning of a glacial inception that is characterized by an abrupt SST decrease, followed by high frequency SST oscillations, and large amounts of freshwater input. This suggests a climatic change from interglacial to glacial conditions linked to the start of ice sheets growth (enrichment of d18O) and the AMOC slowdown resulting in an enhanced cooling of the mid-latitudes.

A high-resolution study of the MIS 12/MIS 11 transition and the MIS 11 (430–376 kyr) coccolithophore assemblages at Ocean Drilling Program Site 977 was conducted to reconstruct the palaeoceanographic and climatic changes in the Alboran Sea from the variability in surface water conditions. The nannofossil record was integrated with the planktonic oxygen and carbon stable isotopes, as well as the Uk'37 Sea Surface Temperature (SST) at the studied site during the investigated interval. The coccolithophore primary productivity, reconstructed from the PPP (primary productivity proxy = absolute values of Gephyrocapsa caribbeanica + small Gephyrocapsa group) revealed pronounced fluctuations, that were strongly associated with variations in the intensity of the regional Alboran Upwelling System. The comparison of the nannoplankton record with opal phytolith content for the studied site and the already available pollen record at the nearby Integrated Ocean Drilling Program Site U1385, suggests an association of the upwelling dynamics with the variability of the North Atlantic Oscillation-like (NAO-like) phase. High PPP during positive (+) NAO-like phases is the result of intensified upwelling, owing to the complete development of the surface hydrological structures at the Alboran Sea. This scenario was identified during the MIS 12/MIS 11 transition (428-422 kyr), the late MIS 11c (405-397 kyr), and MIS11 b to MIS 11a (397-376 kyr). Two short-term minima in the PPP and SST were observed during MIS 11 b and were coeval with the North Atlantic Heinrich-type (Ht) events Ht3 (∼390 kyr) and Ht2 (∼384 kyr). Increased abundance of the subpolar Coccolithus pelagicus subsp. pelagicus and Gephyrocapsa muellerae was consistent with the inflow of cold surface waters into the Mediterranean Sea during the Ht events. Lowered PPP during negative (−) NAO-like phases is the result of moderate upwelling by the incomplete development of surface hydrological structures at the Alboran Sea. This scenario is expressed during the early MIS 11c (422-405 kyr). Overall, the results of our study provide evidence of the important role of atmospheric circulation patterns in the North Atlantic region for controlling phytoplankton primary production and oceanographic circulation dynamics in the Western Mediterranean during MIS 11., This work was supported by the FPU contract of the Ministry of Education and Professional Formation of the Spanish government [FPU17/03349] awarded to A. González-Lanchas and by the financing infrastructure provided by the programs of the Ministry of Economy and Competitiveness [CGL 2015-68459-P] and the Ministry of Science, Innovation and Universities [RTI 2018-099489-B-100] granted to the GGO (Grupo de Geociencias Oceánicas) of the University of Salamanca. DO acknowledges funding from Portuguese Foundation for Science and Technology (FCT) through the CCMAR Research Unit - project UIDB/04326/2020 and contract (CEECIND/02208/2017). The authors thank Editor Antje Voelker and the two anonymous reviewers for their valuable comments and suggestions.

Marine Isotope Stage (MIS) 13, ∼533–478 ka, has received particular attention due to the unexpected enhancement of monsoon systems under a cool climate characterized by lower atmospheric CO2 and larger ice volume than many other interglacials. Key questions remain about its regional expression (intensity, climate variability, length), and underlying forcing factors, in particular at the mid-latitudes. Here we examine the SW Iberian vegetation, terrestrial climate and sea surface temperature (SST) variability during MIS 13 by combining pollen and biomarker data from IODP Site U1385 with climate-model experiments. We show, for the first time, that despite strong precessional forcing, MIS 13 stands out for its large forest expansions with a reduced Mediterranean character alternating with muted forest contractions, indicating that this stage is marked by a cool-temperate climate regime with high levels of humidity. Results of our data-model comparison reveal that MIS 13 orbitally driven SW Iberian climate and vegetation changes are modulated by the relatively strong ice-sheet forcing. We find that the Northern Hemisphere ice-sheets prescribed at the MIS 13 climate optimum reinforce the insolation effect by increasing the tree fraction and both winter and summer precipitation. We propose that the interactions between ice-sheets and major atmospheric circulation systems may have resulted in the persistent influence of the mid-latitude cells over the SW Iberian region, which led to intensified moisture availability and reduced seasonality, and, in turn, to a pronounced expansion of the temperate forest., Financial support was provided by the Portuguese Foundation for Science and Technology (FCT) through the project CLIMHOL (PTDC/AAC-CLI/100157/2008), ULTImATum (IF/01489/2015), SAICT-45-2017-02 projects (WARM WORLDS: 29897 and HOLMODRIVE: 29029), CCMAR FCT Research Unit - project UIDB/04326/2020, D. Oliveira’s contract (CEECIND/02208/2017), F. Naughton’s contract (IF/01489/2015), T. Rodrigues’s contract (WarmWorld- PTDC/CTA-GEO/29897/2017), Voelker’s contract (IF/01500/2014), and WarmClim, a LEFE-INSU IMAGO project. D. Oliveira acknowledges the fundng provided by the L’Oréal Portugal Medal of Honour for Women in Science 2018 from L’Oréal, FCT and UNESCO. M. Alonso-Garcia acknowledges funding from FCT through the CINNAMOW project (PTDC/MAR-PRO/3396/2014) and the Spanish Ministry of Science through the grant RTI2018-099489-B-I00. Q. Yin is a Research Associate of the Belgian National Fund for Scientific Research (FRS-FNRS). Computational resources have been provided by the supercomputing facilities of the Université catholique de Louvain (CISM/UCL) and the Consortium des Equipements de Calcul Intensif en Fédération Wallonie Bruxelles (CECI) funded by FRS-FNRS. We would like to thank the scientists and technicians of IODP Expedition 339, the Bremen Core Repository, L. Devaux for technical assistance, V. Hanquiez for drawing Fig. 1., and two anonymous reviewers for their constructive comments.

Injuries sustained by the pelvic floor muscles during childbirth are one of the major risk factors for the development of pelvic floor dysfunctions. The ability to predict the loss of the tissue integrity and the most affected regions prior to the childbirth would represent a compelling difference in choosing the appropriate management of labour. Previous biomechanical studies, using the finite element method, were able to simulate a vaginal delivery and analyse the mechanical effects on the pelvic floor muscles during the passage of the foetus. Complementing these studies, the aim of this work is to improve the characterization of the pelvic floor muscles, by using an anisotropic visco-hyperelastic constitutive model, including a continuum mechanics damage model. Viscoelasticity is a key feature to obtain more realistic results since biological tissues present relaxation effects that allow larger deformations without damage. This work analyses the reaction forces and the loss of tissue integrity sustained by the pelvic floor and evaluates the effects of different durations of labour. A delaying pushing technique of rest and descend is also studied in this work. The results obtained showed that the reaction forces vary with the duration of labour, with higher force levels associated with higher stretch rates. The pubovisceral muscle is the most affected of the levator ani, presenting an affected region of approximately 30%. The relaxation properties of the tissue contribute to diminish the damage levels, supporting the theory of delayed pushing applied in the second stage of labour.

This paper seeks to discuss the education of the physicians from the Medicine Schools of the urban Studia Generalia in 13th century. The Education methodology was the same at the four fields of knowledge, Arts, Teology, Roman and Canon Law and Medecine. This metodology includes lecture by the scholars and scholastics commentaires and questions by the masters. In three European National Libraries, there are the manuscripts sources and print editions written by the Portuguese physician Petrus Hispanus (?1220-1277), when he had taught at Siena (1246-1252). The three libraries are: France, Spain and Vatican. El artículo trata de investigar, em lo siglo XIII, la educación de los físicos em las Escuelas de Medicina en los Studia Generalia, localizados en los centros urbanos. La metodologia llamada escolástica era um razgo común a las quatro áreas del conocimiento, Artes, Teologia, Derecho Canonico y Romano. El método incluya la lectura (lectio), los comentários y las quaestiones de los textos de las autoridades antiguas y medievales por los maestros. Hay fuentes manuscritas de los comentários y quaestiones escolásticas del físico Pedro Hispano em tres bibliotecas europeas: Biblioteca Apostólica Vaticana, Biblioteca Nacional de España y Biblioteca Nacional de Francia. O presente texto busca problematizar a educação e a formação dos físicos nas faculdades de Medicina dos Estudos Gerais urbanos, no século XIII. A metodologia de ensino era comum à todas as quatro áreas do conhecimento universitário, Artes, Teologia, Direito Canônico e Romano e Medicina. Consistia em leitura pelos escolares e comentários e questões pelos mestres acerca dos textos das autoridades antigas e medievais. Em três bibliotecas nacionais europeias encontram-se as fontes manuscritas e edições impressas dos comentários e questões escritos pelo físico português Pedro Hispano (?1220-1277), quando atuou como mestre na Faculdade de Medicina de Siena entre 1246-1252. São elas: a da França, a de Espanha e a do Vaticano.

Childbirth-related trauma is a recurrent and widespread topic due to the disorders it can trigger, such as urinary and/or anal incontinence, and pelvic organ prolapse, affecting women at various levels. Pelvic floor dysfunction often results from weakening or direct damage to the pelvic floor muscles (PFM) or connective tissue, and vaginal delivery is considered the primary risk factor. Elucidating the normal labor mechanisms and the impact of vaginal delivery in PFM can lead to the development of preventive and therapeutic strategies to minimize the most common injuries. By providing some understanding of the function of the pelvic floor during childbirth, the existing biomechanical models attempt to respond to this problem. These models have been used to estimate the mechanical changes on PFM during delivery, to analyze fetal descent, the effect of the fetal head molding, and delivery techniques that potentially contribute to facilitating labor and reducing the risk of muscle injury.

The Iberian Peninsula, at North Atlantic mid-latitude and the western extreme of the European continent, is a key point for climate reconstructions. This work provides multi-proxy records measured in 8 inner-shelf sediment cores from 5 sites located between South Portugal (Algarve) and Northwest Spain (Galiza) (36 to 41º N) and target a regional reconstruction of climate variability during the Historic period (last 2 ky). The SST records reveal a long-term scale cooling (±1 ºC/2 ky) that ends at the beginning of the 20th century at all latitudes. This cooling is a follow up of the cooling process that started in the early Holocene driven by a decrease in summer insolation in the Northern Hemisphere. Within this long term SST variability multi-decadal/centennial scale variability is detected along Iberia. The different latitudinal SST reconstructions jointly with a determined regional SST stack were compared to on-land precipitation from higher plant n-alkanes and pollen data, to assess the relationship between hydroclimate (drought and/or precipitation) and SST. Regional variability is overall in consonance with NE Spain, and other European and north Hemisphere reconstructions. Warm conditions prevailed throughout 1300 yr, encompassing the Roman Period (RP), the Dark Ages (DA) and the Medieval Warm Period (MWP). The initial cooling at 1300 CE leads to 4 centuries of ±1 ºC colder mean SSTs contemporaneous with the Little Ice Age (LIA). The transition towards the Industrial Era starts by 1800 CE with a rise to pre-LIA SSTs. Climate specificities have been detected in western Iberian margin records and reveal the existence of two distinct phases within the MWP and a two-step SST increase towards the Industrial Era. The intense precipitation/flooding and warm winters but cooler intermediate seasons observed for the early MWP imply the interplay of internal oceanic variability with the three known atmospheric circulation modes, AMO, EA and SCAND in a positive phase. The late MWP, typified by drier and cooler winters and warmer intermediate seasons calls for a change in sign of the SCAND. A stronger mark of oceanic influences on western Iberian Peninsula (IP) starts with the transition to the Industrial Era.

The vaginal birth is the leading cause of pelvic floor muscle injuries compromising its function, which can lead to pelvic organ prolapse, urinary incontinence, and other pelvic disorders. These conditions affect many women’s quality of life. As such, biomechanical models emerge to analyze the impact of pregnancy and childbirth in the biomechanics of the pelvic floor, and determine features that potentially contribute to complications during vaginal delivery. Computer models allow structural hypotheses to be analyzed, such as the influence of the shape of the fetal head and its position at delivery, the consequence of specific obstetrical procedures, among others. Damage analysis is especially important to understand the pathophysiology of the associated dysfunctions. The continuous developments in imaging techniques, and the increased computing power, make possible for these frameworks to be clinically valuable, with customized computer models and subject-specific mechanical properties, both in useful time.

Current evidence points to a high prevalence of urinary incontinence among female athletes. In this context, this study aims to assess if structural and biomechanical characteristics of the pubovisceral muscles may lead to urine leakage. Clinical and demographic data were collected, as well as pelvic Magnetic Resonance Imaging. Furthermore, computational models were built to verify if they were able to reproduce similar biomechanical muscle response as the one measured by dynamic imaging during active contraction by means of the percent error. Compared to the continent ones (n=7), incontinent athletes (n=5) evidenced thicker pubovisceral muscles at the level of the midvagina (p=0.019 and p=0.028 for the right and left sides, respectively). However, there were no differences neither in the strength of contraction in the Oxford Scale or in the displacement of the pelvic floor muscles during simulation of voluntary contraction, which suggests that urine leakage may be related with alterations in the intrafusal fibers than just the result of thicker muscles. Additionally, we found similar values of displacement retrieved from dynamic images and numerical models (6.42 ± 0.36 mm vs. 6.10 ± 0.47 mm; p=0.130), with a percent error ranging from 1.47% to 17.20%. However, further refinements in the mechanical properties of the striated skeletal fibers of the pelvic floor muscles and the inclusion of pelvic organs, fascia and ligaments would reproduce more realistically the pelvic cavity.

CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais Objective: To translate the Early Clinical Assessment of Balance (ECAB), an assessment scale developed specifically for children and adolescents with cerebral palsy into Brazilian Portuguese, evaluate semantic, idiomatic, experiential and conceptual equivalences, and to examine the face validity and the reliability within and between examiners of the Brazilian version. Methods: The following steps were done: translation by two independent translators; synthesis of translations; back translation into English; analysis of back-ranslations by a multidisciplinary committee and the author of the test to develop the final version of the test; test application training; administration of the translated version of ECAB (videotaped) in 60 children and adolescents with cerebral palsy; intra and inter-examiner reliability assessment. Reability was assessed by intraclass correlation coefficient (CCI). Results: The discrepancies found were related mainly to semantic equivalence and, therefore, there was no need to make cultural adaptations in any of the 13 items on the scale. The rate of agreement was greater than 90% and the reliability of the ECABPortuguese total score was excellent both for the intra-rater test (CCI=1.00) and for the inter-rater test (CCI=0.998). Likewise, the reliability evaluation of each of the scale items was also excellent. Conclusions: The translated version of the ECAB into Portuguese provides a tool for the evaluation of the specific balance for children and adolescents with cerebral palsy with different levels of functioning. Objetivo: Traduzir a Early Clinical Assessment of Balance (ECAB), escala de avaliação do equilíbrio desenvolvida especificamente para crianças e adolescentes com paralisia cerebral (PC) para a língua portuguesa do Brasil; avaliar as equivalências semânticas, idiomáticas, experiencial e conceituais; e examinar a validade de face e a confiabilidade intra e interavaliadores da versão brasileira. Métodos: Estudo envolveu tradução do instrumento por dois tradutores independentes; síntese das traduções; retrotradução para o inglês; análise das retrotraduções por um comitê multidisciplinar; treinamento; administração da versão traduzida da ECAB (gravadas em vídeo) em 60 crianças e adolescentes com PC; e avaliação da confiabilidade intra e interexaminadores. A confiabilidade foi avaliada por meio do coeficiente de correlação intraclasse (CCI). Resultados: As discrepâncias encontradas foram referentes principalmente à equivalência semântica e, portanto, não houve necessidade da realização de adaptações culturais em nenhum dos 13 itens da escala. A taxa de concordância foi maior que 90%, e a confiabilidade do escore total da ECAB-português foi excelente tanto para o teste intra-avaliador (CCI=1,00) quanto para interavaliadores (CCI=0,998). Da mesma forma, a avaliação da confiabilidade de cada um dos itens da escala também foi excelente. Conclusões: A versão traduzida da ECAB para o português disponibiliza, para os profissionais da reabilitação infantil, um instrumento confiável de avaliação do equilíbrio específico para crianças e adolescentes com PC com diferentes níveis de funcionalidade.

Vaginal childbirth is the leading cause of pelvic floor muscles injury, which contributes to pelvic floor dysfunction, being enhanced by fetal malposition. Therefore, the aim of the present study is to verify the influence of mediolateral episiotomies in the mechanics of the pelvic floor with the fetus in occiput posterior position when compared to the occiput anterior position. Numerical simulations of vaginal deliveries, with and without episiotomy, are performed based on the Finite Element Method. The biomechanical model includes the pelvic floor muscles, a surface to delimit the anterior region of the birth canal and a fetus. Fetal malposition induces greater extension of the muscle compared to the normal position, leading to increases of stretch. The faster enlargement may be responsible for a prolonged second stage of labor. Regarding the force required to achieve delivery, the difference between the analyzed cases are 35 N, which might justify the increased need of surgical interventions. Furthermore, episiotomy is essential in reducing the damage to values near the ones obtained with normal position, making the fetal position irrelevant. These biomechanical models have become extremely useful tools to provide some understanding of pelvic floor function during delivery helping in the development of preventative strategies.

During vaginal delivery, women sustain stretching of their pelvic floor, risking tissue injury and adverse outcomes. Realistic numerical simulations of childbirth can help in the understanding of the pelvic floor mechanics and on the prevention of related disorders. In previous studies, biomechanical finite element simulations of a vaginal delivery have been performed disregarding the viscous effects present on all biological soft tissues. The inclusion of the viscoelastic behaviour is fundamental, since it allows to investigate rate-dependent responses. The present work uses a viscohyperelastic constitutive model to evaluate how the childbirth duration affects the efforts sustained by the pelvic floor during delivery. It was concluded that viscoelasticity adds a stiffness component that leads to higher forces comparing with the elastic response. Viscous solutions are rate dependent, and precipitous labours could be associated to higher efforts, while lower reaction forces were denoted for normal and prolonged labours, respectively. The existence of resting stages during labour demonstrated the capability of the tissue to relax and recover some of the initial properties, which helped to lower the forces and stresses involved. The present work represents a step further in achieving a robust non-invasive procedure, allowing to estimate how obstetrical factors influence labour and its outcomes.

Vaginal delivery is commonly accepted as a risk factor in pelvic floor dysfunction; however, other obstetric procedures (episiotomy) are still controversial. In this work, to analyze the relationship between episiotomy and pelvic floor function, a finite element model of the pelvic cavity is used considering the pelvic floor muscles (PFMs) with damaged regions from spontaneous vaginal delivery and from deliveries with episiotomy. Common features assessed at screening of pelvic floor dysfunction are evaluated during numerical simulations of both Valsalva maneuver and contraction. As stated in literature, a weakening of the PFM, represented by damaged regions in the finite element model, would lead to a bladder neck hypermobility measured as a variation between the α angle (angle between the bladder neck and the symphysis pubis line and the midline of the symphysis) during straining and withholding. However, the present work does not associate bladder neck hypermobility to a more damaged muscle, suggesting that other supportive structures also play an important role in the stabilization of the pelvic organs. Furthermore, considering passive behavior of the PFM, independently of the amount of damage considered, the resultant displacements of the pelvic structures are the same. Regarding the PFM contraction, the less the muscle is damaged, the greater the movements of the pelvic organs. Furthermore, the internal organs of the female genital system are the most affected by the unhealthy of the PFM. Additionally, the present study shows that the muscle damage affects more the active muscle component than the passive.