Looking for the key to preservation of fossil marine vertebrates in the Pisco Formation of Peru: new insights from a small dolphin skeleton

The upper Neogene Pisco Formation of Peru is known worldwide as one of the most significant Cenozoic marine vertebrate Konservatt-Lagerstätten, even featuring cetacean specimens that retain remains of soft tissues or stomach contents. Previous works showed that biomediated precipitation of dolomite concretions around large-sized decaying carcasses was one of the most relevant processes responsible for exceptional fossil preservation. In turn, little is known about the modes of fossilization of well-preserved small-sized vertebrates, which are rather common in the Pisco Formation, but mostly do not exhibit dolomite concretions. We report on a cetacean specimen, identified as belonging to the extinct short-snouted, small dolphin species Brachydelphis mazeasi (Pontoporiidae), preserved within a late Miocene sandy deposit at the site of Pampa Corre Viento. This specimen consists of a moderately disarticulated partial skeleton exhibiting well-mineralized bones; it is not enclosed within a dolomite concretion, being however delimited by an evident dark boundary in the host sediment. Scanning electron microscopy and microanalytical investigations identify Mn-oxides and apatite as early diagenetic minerals around the skeleton. We argue that a rapid burial of the specimen was pivotal for the preservation of the bones, and allowed the early establishment of anoxic processes for degradation of organic matter. Coupled with availability of P in porewater, the reducing conditions and the lowered pH allowed precipitation of Ca-phosphate while increasing Mn solubility close to the pontoporiid carcass. Mn-oxides precipitated at the redox boundary, the latter defining the outer edge of the volume of sediment affected by altered chemical conditions due to the decaying processes. The permeability of the sediment and the small size of the carcass were possible factors unfavorable to extensive sulfate reduction, thus preventing the formation of a dolomite concretion and allowing bone phosphatization. This record emphasizes the role of conditions favorable to bone mineralization in absence of an isolating carbonate concretion, in cases of high quality preservation of small-sized vertebrates observed in the Pisco Formation. The observation of patterns in the distribution of diagenetic minerals in the sediment enclosing vertebrate remains without, or with limited carbonate concretions provides insights into early taphonomic processes

Analysis of polycyclic aromatic hydrocarbons (PAHs) and their derivatives in biochar treated stormwater

Polycyclic aromatic hydrocarbons (PAHs), oxygenated PAHs (oxy-PAHs) and nitrogen heterocyclic polycyclic aromatic compounds (N-PACs) are persistent and semi-volatile organic compounds primarily formed due to incomplete combustion of organic material or, in the case of the derivatives, through transformation reactions of PAHs. Their presence in the environment is ubiquitous and many of them have been proven carcinogenic, teratogenic, and mutagenic. These toxic pollutants can therefore pose a threat to both ecosystem and human health and urges for remediation strategies for PAHs and derivatives from water bodies. Biochar is a carbon-rich material resulting from the pyrolysis of biomass resulting in a very porous matter with high surface area for an enhanced interaction with chemicals. This makes biochar a promising alternative for filtering micropollutants from contaminated aquatic bodies. In this work, a previously developed and validated methodology for the analysis of PAHs, oxy-PAHs and N-PACs in surface water samples was adapted for its utilization in biochar treated stormwater with special emphasis on scaling down the solid-phase extraction as well as including an additional filtering step for the removal of particulate matter in the media. & BULL; Optimized extraction method for PAHs, oxy-PAHs and N-PACs from stormwater treated with biochar. & BULL; Biochar strongly impacts the stormwater matrix and, therefore, additional steps are required in the extraction methodology. & BULL; Solid-phase extraction combined with GC-MS have been used to analyse PAHs, oxy-PAHs and N-PACs in stormwater treated with biochar

Seasonal ocean upwelling recorded by the late Miocene Pisco Formation diatomites of Peru

A 25-cm-thick sample of diatomaceous mudstone was collected in the whale fossil-bearing late Miocene Pisco Formation at Cerro Los Quesos in Peru. This macroscopically-laminated sample was divided into blocks and embedded in epoxy resin for light and scanning electron microscope (SEM) analysis. In only a few cases are laminae well preserved and, hence, useful for paleoenvironmental studies. In these few cases, a terrigenous lamina – Coscinodiscus ooze lamina – mixed lamina (Chaetoceros resting spores, Thalassionema, terrigenous material) sequence is observed. By comparison with Holocene sediment laminations from the Gulf of California, the late Miocene Peruvian triplet laminations are interpreted as an annual depositional cycle. The terrigenous lamina was deposited in the wet season (summer). Coscinodiscus ooze was the product of: (1) initial high summer primary production which took place at the thermocline during water column stratification; and (2) a subsequent ‘Fall dump’, or sedimentation, of the diatoms due to autumn storm-related mixing of the water column. Finally, the mixed lamina was deposited during/following the spring bloom. The frequent disruption or homogenisation of laminae observed in the slides was attributed to bioturbation by microbenthic organisms. This bioturbation was accompanied by a general absence of macrobenthos in the late Miocene diatomites of the Pisco Formation; such conditions are commonly interpreted as the consequence of a suboxic sea floor environment. In this presentation we will demonstrate the seasonal nature of the Late Miocene Pisco Formation diatomites and show novel SEM microelemental maps that help interpreting the paleonvironmental conditions at the sea floor at the time of diatomites deposition

Hedging in the ethanol and sugar production: integrating financial and production decisions

Abstract Agricultural producers face financial risk at the moment of final products selling. This imposes the use of instruments to reduce risks in order to assure prices and production process economic feasibility. This paper examines the problem of creating hedging strategies with production constraints and proposes a deterministic multi-period optimization model to solve it. Uncertainty was introduced in the model through scenario trees and risk was analyzed according to the traditional mean variance approach. The model was analyzed for the sugar and ethanol market in order to aid in the financial management of a sugar cane refinery

Inside baleen: Exceptional microstructure preservation in a late Miocene whale skeleton from Peru

Exceptionally preserved delicate baleen microstructures have been found in association with the skeleton of a late Miocene balaenopteroid whale in a dolomite concretion of the Pisco Formation, Peru. Microanalytical data (scanning electron microscopy, electron probe microanalysis, X-ray diffraction) on fossil baleen are provided and the results are discussed in terms of their taphonomic and paleoecological implications. Baleen fossilization modes at this site include molding of plates and tubules, and phosphatization. A rapid formation of the concretion was fundamental for fossilization. We suggest that the whale foundered in a soft sediment chemically favorable to rapid dolomite precipitation, allowing the preservation of delicate structures. Morphometric considerations on the baleen plates and bristles coupled with the reconstructed calcification of the latter permit speculation on the trophic preferences of this balaenopteroid whale: the densely spaced plates and the fine and calcified bristles provide evidence for feeding on small-sized plankton, as does the modern sei whale

Hedging in the ethanol and sugar production: integrating financial and production decisions

Abstract Agricultural producers face financial risk at the moment of final products selling. This imposes the use of instruments to reduce risks in order to assure prices and production process economic feasibility. This paper examines the problem of creating hedging strategies with production constraints and proposes a deterministic multi-period optimization model to solve it. Uncertainty was introduced in the model through scenario trees and risk was analyzed according to the traditional mean variance approach. The model was analyzed for the sugar and ethanol market in order to aid in the financial management of a sugar cane refinery

Role of Serum Cholesterol and Statin Use in the Risk of Prostate Cancer Detection and Tumor Aggressiveness

The aim of this study was to analyze the relationship between statin use along with serum cholesterol levels and prostate cancer (PCa) detection and aggressiveness. Statin users of three years or more and serum cholesterol levels (SC) were assessed in 2408 men scheduled for prostate biopsy. SC was classified as normal (NSC: 200 mg/dL). High-grade PCa (HGPCa) was considered if the Gleason score was greater than 7. Statin users comprised 30.9% of those studied. The PCa detection rate was 31.2% of men on statins and 37% of non-statin users (p < 0.006). The PCa detection rate was 26.3% in men with NSC and 40.6% in those with HSC (p < 0.001). In the subset of NSC men, the PCa rate was 26.5% for statin users and 26.2% for non-users (p = 0.939), while in men with HSC, the PCa rate was 36.4% for statin users and 42.0% for non-statin users (p = 0.063). The HGPCa rate was 41.8% for statin users and 32.5% for non-users (p = 0.012). NSC men had a 53.8% rate of HGPCa, while the rate was only 27.6% in HSC men (p < 0.001). NSC men on statins had an HGPCa rate of 70.2%, while non-statin users had a rate of 41.2% (p < 0.001). The HGPCa rate for HSC men on statins was 18.8%, while the rate was 30.0% (p = 0.011) for non-users. Logistic regression analysis suggested that serum cholesterol levels could serve as an independent predictor of PCa risk, OR 1.87 (95% CI 1.56-2.24) and HGPCa risk, OR 0.31 (95% CI 0.23-0.44), while statin usage could not. Statin treatment may prevent PCa detection through serum cholesterol-mediated mechanisms. A disturbing increase in the HGPCa rate was observed in statin users who normalized their serum cholesterol

Role of Serum Cholesterol and Statin Use in the Risk of Prostate Cancer Detection and Tumor Aggressiveness

The aim of this study was to analyze the relationship between statin use along with serum cholesterol levels and prostate cancer (PCa) detection and aggressiveness. Statin users of three years or more and serum cholesterol levels (SC) were assessed in 2408 men scheduled for prostate biopsy. SC was classified as normal (NSC: 200 mg/dL). High-grade PCa (HGPCa) was considered if the Gleason score was greater than 7. Statin users comprised 30.9% of those studied. The PCa detection rate was 31.2% of men on statins and 37% of non-statin users (p < 0.006). The PCa detection rate was 26.3% in men with NSC and 40.6% in those with HSC (p < 0.001). In the subset of NSC men, the PCa rate was 26.5% for statin users and 26.2% for non-users (p = 0.939), while in men with HSC, the PCa rate was 36.4% for statin users and 42.0% for non-statin users (p = 0.063). The HGPCa rate was 41.8% for statin users and 32.5% for non-users (p = 0.012). NSC men had a 53.8% rate of HGPCa, while the rate was only 27.6% in HSC men (p < 0.001). NSC men on statins had an HGPCa rate of 70.2%, while non-statin users had a rate of 41.2% (p < 0.001). The HGPCa rate for HSC men on statins was 18.8%, while the rate was 30.0% (p = 0.011) for non-users. Logistic regression analysis suggested that serum cholesterol levels could serve as an independent predictor of PCa risk, OR 1.87 (95% CI 1.56-2.24) and HGPCa risk, OR 0.31 (95% CI 0.23-0.44), while statin usage could not. Statin treatment may prevent PCa detection through serum cholesterol-mediated mechanisms. A disturbing increase in the HGPCa rate was observed in statin users who normalized their serum cholesterol

In situ Clinical Simulations in Primary Care applied to emergency training

[EN] A study with a mixed quantitative-qualitative methodology was designed to assess the use of on-site Clinical Simulations in Primary Care applied to training in Myocardial Infarction (MI) Code, Stroke Code, and cardio-pulmonary resuscitation. A total of 95 surveys were completed, and 2 focus groups were conducted with 19 healthcare workers from a health center, representing various professional profiles. Participants expressed the opinion that the training improved their self-confidence and long-term knowledge, and had been very useful and interesting, as it allowed them to practice aspects impossible to address through other types of training (e.g. material localization). They highlighted the importance of leadership in emergency care and enhanced teamwork. Professionals preferred this methodology for future training activities.Lacasta-Tintorer, D.; Esplugas-Muñoz, N.; Estafanell-Celma, A.; Tajada-Vitales, C.; Bielsa-Pascual, J.; Moreno-Gabriel, E.; Toran-Montserrat, P. (2024). In situ Clinical Simulations in Primary Care applied to emergency training. Editorial Universitat Politècnica de València. https://doi.org/10.4995/HEAd24.2024.1725