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Over the lifetime of an animal, metabolic processes in the body maintain bone tissues in a dynamic state of equilibrium. After the death of the organism, bone tissues undergo diagenesis, an intense transformation that affects its physicochemical constitution. Although many recent works have greatly contributed to the understanding of the processes surrounding diagenesis, there is still much yet to be understood about this multifaceted phenomena. In this work, XRF and microCT were used to characterize the specimen elemental configuration and investigate the fossilization process of a recovered Puma concolor (cranium, mandible and teeth elements), found submerged in a lake in the Impossível‐Ioiô Cave System (Bahia, Brazil). MicroCT enabled the identification of the density distribution throughout the specimens, which were used as reference to XRF analyses. The XRF spectra of the analyzed specimen showed the presence of 11 elements: P, Cl, Ca, Mn, Fe, Cu, Zn, Br, Sr, Y and Hg. Yttrium counts proved to be regular throughout the specimen surface and decreased in the interface between bone surface and interior, evidencing their correspondence to sample environmental exposure. Furthermore, a correlation between fossil surface coloration, element configuration and density is presented. The relatively low presence of Fe and Y in the enamel elicits its elementary and structural preservation. The combined results contribute to the understanding of the physicochemical process of paleomastozoological fossilization, further enriching the comprehension of the process of fossilization in a submerged environment. [ABSTRACT FROM AUTHOR]

Ionospheric scintillation and fading events over low‐latitude regions are often caused by severely depleted geomagnetic field‐aligned structures known as Equatorial Plasma Bubbles. These events are subject of interest to scientific investigations and concern to technological applications. Over the past several years, most of scintillation studies have focused on the dependence of these events on density gradients, location, local time, geomagnetic conditions, and so forth. This work presents a discussion about the role of the alignment between the signal propagation path and the depleted structures or, equivalently, the geomagnetic field lines, on the observed scintillation and deep fading characteristics. Data from three stations (dip latitudes: 16.13°S, 19.87°S, and 22.05°S) located around the Equatorial Ionization Anomaly (EIA) region were used to assess the amplitude scintillation severity and the deep fading events features under aligned and nonaligned conditions. The results show that the alignment condition plays a crucial role in the occurrence of strong scintillation. The study also revealed that, as stations far from the crests of the EIA are considered, the alignment influence seems to increase, and that a combination of strong plasma density fluctuation and increased aligned path is, presumably, the configuration under which the most severe scintillation and drastic deep fading events are observed. The results indicate that this conjunction is typically met in regions somewhat distinct from that with largest plasma density background over the Brazilian region, therefore, strongest scintillation and largest deep fading rates were observed by a station slightly off‐the EIA peak. Plain Language Summary: Several phenomena from space weather affect technological applications dependent on positioning systems relying on information from the Global Navigation Satellite System. Over low‐latitude regions the most prominent events are the Equatorial Plasma Bubbles. These plasma bubbles are depleted structures that may reach thousands of km and affect radio signals causing deep fading events and the so‐called ionospheric scintillation. Very often the studies regarding plasma bubbles and the ensuing ionospheric scintillation and deep fading events consider the plasma density deviation caused by the presence of these plasma bubbles over a region with enhanced background plasma density, as is the case of the Equatorial Ionization Anomaly, however, this work shows that other aspects must also be considered. In this work scintillation data from ground receivers deployed over the southern Brazilian region during a period of intense occurrence of scintillation were used to uncover new aspects responsible for severe scintillation and deep fading events. It was shown that the alignment between the transionospheric signals and the plasma bubbles is related to the severe scintillation and to the increase in the deep fading events rate. It was also found that the conjoint configuration of strong plasma density deviation and increased alignment is probably responsible for the more drastic events. Key Points: Space weather impacts on Global Navigation Satellite System communication over low‐latitude regionsEquatorial plasma bubbles field‐aligned nature and its influence on transionospheric signals aligned with these depleted plasma structuresIonospheric scintillation and deep fading characteristics according to the propagation path [ABSTRACT FROM AUTHOR]

Aim To investigate the cytotoxicity, osteogenic bioactivity and mRNA expression of osteogenic markers of bone morphogenetic protein 2 ( BMP-2), osteocalcin ( OC) and alkaline phosphatase ( ALP) induced by the extracts of set MTA Plus ( MTA P) (Avalon Biomed Inc. Bradenton, FL, USA) in comparison with MTA (Angelus, Londrina, PR, Brazil) on human dental pulp cells ( hDPCs). Methodology Cell viability was assessed by mitochondrial dehydrogenase enzymatic ( MTT) assay, and the mechanism of cell death was evaluated by flow cytometry. Bioactivity was evaluated by alkaline phosphatase ( ALP) assay and detection of calcium deposits with alizarin red staining ( ARS). The gene expression of BMP-2, OC and ALP was quantified with real-time PCR. Statistical analysis was performed with analysis of variance and Bonferroni or Tukey post-test (α = 0.05). Results MTA and MTA P were not cytotoxic and did not induce apoptosis. MTA P had significant higher ALP activity in relation to MTA and the control ( P < 0.05). MTA had a significantly higher percentage of mineralized area than MTA P ( P < 0.05). The expression of BMP2 and OC mRNA was significantly higher in cells exposed to MTA than MTA P after 1 day ( P < 0.05). At day 3, the mRNA expression of ALP was significantly higher in MTA P compared with MTA ( P < 0.05). Conclusions MTA and MTA Plus were noncytotoxic, increased mineralization processes in vitro and induced the expression of osteogenic markers. [ABSTRACT FROM AUTHOR]

Underplatform dampers (UPD) are commonly used in aircraft engines to mitigate the risk of high-cycle fatigue failure of turbine blades. The energy dissipated at the friction contact interface of the damper reduces the vibration amplitude significantly, and the couplings of the blades can also lead to significant shifts of the resonance frequencies of the bladed disk. The highly nonlinear behaviour of bladed discs constrained by UPDs requires an advanced modelling approach to ensure that the correct damper geometry is selected during the design of the turbine, and that no unexpected resonance frequencies and amplitudes will occur in operation. Approaches based on an explicit model of the damper in combination with multi-harmonic balance solvers have emerged as a promising way to predict the nonlinear behaviour of UPDs correctly, however rigorous experimental validations are required before approaches of this type can be used with confidence. In this study, a nonlinear analysis based on an updated explicit damper model having different levels of detail is performed, and the results are evaluated against a newly-developed UPD test rig. Detailed linear finite element models are used as input for the nonlinear analysis, allowing the inclusion of damper flexibility and inertia effects. The nonlinear friction interface between the blades and the damper is described with a dense grid of 3D friction contact elements which allow accurate capturing of the underlying nonlinear mechanism that drives the global nonlinear behaviour. The introduced explicit damper model showed a great dependence on the correct contact pressure distribution. The use of an accurate, measurement based, distribution, better matched the nonlinear dynamic behaviour of the test rig. Good agreement with the measured frequency response data could only be reached when the zero harmonic term (constant term) was included in the multi-harmonic expansion of the nonlinear problem, highlighting its importance when the contact interface experiences large normal load variation. The resulting numerical damper kinematics with strong translational and rotational motion, and the global blades frequency response were fully validated experimentally, showing the accuracy of the suggested high detailed explicit UPD modelling approach. [ABSTRACT FROM AUTHOR]

Correct interpretation of the urinary sodium concentration (NaU) and its relation to renal function in critically ill patients is lacking. Our aim was to evaluate the relationship between simultaneous NaU value and serum creatinine (sCr). The hypothesis is that a NaU value greater than 140 mmol/l (normal equivalent value in plasma) is only found in patients with normal sCr. We made a retrospective analysis of 1153 simultaneous samples of NaU and sCr, divided according to diuretic use in the previous 24 hours and grouped in five distinct NaU ranges (< 20, 20 to 39, 40 to 139, 140 to 169, ≥ 170 mmol/l). NaU values below 140 mmol/l were found simultaneously with both normal and increased sCr. NaU values above 140 mmol/l were almost always found in patients with normal sCr, even if diuretics were used. Median sCr values in the NaU ranges above 140 mmol/l were significantly lower than in the other NaU ranges. Estimated glomerular filtration rates were lower and intensive care unit and hospital mortalities were higher in patients with NaU values lower than 140 mmol/l compared to patients with a NaU higher than 140 mmol/l. We concluded that a high natriuretic capacity reflects significant residual renal function in the critically ill. NaU greater than normal plasma sodium is a possible biomarker of normal/improving renal function and also of better outcome. Sole NaU values below 140 mmol/l are difficult to interpret but it is possible that very low NaU values may signify some threat to normal kidney function and worse prognosis even in the presence of normal sCr. Our way to interpret NaU values in critically ill patients needs further careful evaluation. [ABSTRACT FROM AUTHOR]

Improvement of solar-cell efficiency at a minimum possible cost addition is constantly sought, and this is often achieved at incremental percentage steps. Among a number of alternatives, antireflective coatings and surface texturing are the most prominent. This paper presents an alternative texturing method of crystalline silicon in an attempt to improve the efficiency of photon transmission through the surface and collection in the bulk. The method relies on anisotropic etching of bulk silicon and requires only a single oxide mask and two etching steps with a KOH or TMAH aqueous solution. The surface texture consists of smooth hemispherical cavities, which do not demand a lithographic mask or intricate technology processes to obtain the hemispherical cavities. This method can be applied to increase the profile area of the originally flat frontal surface exposed to light and consequently increase the effective width of the depletion region. The latter implies a higher probability of photon collection, contributing to the improvement of the conversion efficiency of the device. The textured nontilted silicon solar-cell transmittance under small solar incidence angles at dawn and sunset is improved compared to a flat surface, increasing the photocurrent. [ABSTRACT FROM AUTHOR]

The Annot syncline is one of the synclinal remnants of the Tertiary Alpine foreland basin, which was mainly structured during the Paleocene and filled during the Eocene-Oligocene by a marine transgressive succession. The upper unit consists in the Annot Sandstone formation deposited in a fan delta-fed turbidite setting. New detailed structural data from the Annot depocentre indicate a progressive limb rotation during deposition of the Annot Sandstone. These data are used to build a 3D model of the syncline in Gocad software that documents turbidite depocentre evolution. Trishear modelling constrains the role and interaction of regional thrusts and fault propagation folds in depocentre development. [ABSTRACT FROM AUTHOR]

Introduction/Objective: Phosphodiesterase-5 inhibitors (PDE5i) are traditionally employed for the management of erectile dysfunction and lower urinary tract symptoms. However, their role in the healing of complex penile wounds remains scarcely discussed. This study aims to describe the case of a 27-year-old man who suffered from penile strangulation, treated with sildenafil. Additionally, a literature review concerning the use of PDE5i for the treatment of complex penile injuries will be conducted. Methods: A 27-year-old man presented to the emergency room after a self-induced penile strangulation using a ring placed at the base of the penis. Extensive necrosis of the corpus cavernosum was identified through magnetic resonance imaging. Considering the psychosocial implications of penile amputation, organ preservation was chosen, and conservative treatment with sildenafil and daily local dressings was initiated. Thirty days after admission, Doppler ultrasound revealed symmetrical corpus cavernosum with normal echogenicity and usual blood flow patterns. Subsequently, the patient underwent superficial necrotic tissue debridement followed by partial skin grafting in a second stage, leading to hospital discharge after 55 days of hospitalization. Results: PDE5 inhibitors enhance nitric oxide bioavailability, promoting vasodilation and improved tissue oxygenation, thereby facilitating various phases of the healing process. Evidence indicates their benefit in microvascular perfusion in skin and soft tissues. Reports suggest satisfactory outcomes of topical PDE5i application in radiation-induced lesions, implying their role in epidermal cell expansion, reduction of inflammatory infiltrates, enhanced vascularization, and decreased collagen deposition. Conclusion: This study presents a successful case of sildenafil use in treatment of a complex penile wound, shedding light on an unconventional application of PDE5i. Financing: No conflict. [ABSTRACT FROM AUTHOR]

Underplatform dampers (UPDs) are commonly used in aircraft engines to limit the risk of high-cycle fatigue of turbine blades. The latter is located in a groove between two consecutive blades. The dry friction contact interface between the damper and the blades dissipates energy and so reduces the vibration amplitudes. Two common geometries of dampers are used nowadays, namely wedge and cylindrical dampers, but their efficiency is limited when the blades have an in-phase motion (or a motion close to it), since the damper tends to have a pure rolling motion. The objective of this study is to analyze a new damper geometry, based on a conical shape, which prevents from this pure rolling motion of the damper and ensures a high kinematic slip. The objective of this study is to demonstrate the damping efficiency of this geometry. Hence, in a first part, the kinematic slip is approximated with analytical considerations. Then, a nonlinear dynamic analysis is performed, and the damping efficiency of this new geometry is compared to the wedge and the cylindrical geometries. The results demonstrate that the conical damper has a high damping capacity and is more efficient and more robust than the two others. [ABSTRACT FROM AUTHOR]

Accurate prediction of the vibration response of aircraft engine assemblies is of great importance when estimating both the performance and the lifetime of their individual components. In the case of underplatform dampers, for example, the motion at the frictional interfaces can lead to a highly nonlinear dynamic response and cause fretting wear at the contact. The latter will change the contact conditions of the interface and consequently impact the nonlinear dynamic response of the entire assembly. Accurate prediction of the nonlinear dynamic response over the lifetime of the assembly must include the impact of fretting wear. A multiscale approach that incorporates wear into the nonlinear dynamic analysis is proposed, and its viability is demonstrated for an underplatform damper system. The nonlinear dynamic response is calculated with a multiharmonic balance approach, and a newly developed semi-analytical contact solver is used to obtain the contact conditions at the blade-damper interface with high accuracy and low computational cost. The calculated contact conditions are used in combination with the energy wear approach to compute the fretting wear at the contact interface. The nonlinear dynamic model of the blade-damper system is then updated with the worn profile and its dynamic response is recomputed. A significant impact of fretting wear on the nonlinear dynamic behavior of the blade-damper system was observed, highlighting the sensitivity of the nonlinear dynamic response to changes at the contact interface. The computational speed and robustness of the adopted multiscale approach are demonstrated. [ABSTRACT FROM AUTHOR]

Granulosa cells (GC) and theca cells (TC) luteinize in culture because of the presence of serum in the medium and, as a consequence, the production of progesterone (P4) increases and that of 17β-estradiol (E2) decreases. The follicular phase of the bovine estrous cycle is characterized by the presence of E2, as well as aromatase activity, that is turned off in the atresia or in the luteal phase of the bovine estrous cycle. We propose to characterize 2 co-culture systems utilizing slices of follicular walls (explants) containing both GC and TC and to cultivate them in nondefined medium (NDM; TCM199+serum) or defined medium (DM; α MEM+polyvinyl alcohol). To prepare the explants, 80 follicles measuring 4 to 6 mm in diameter were selected. Concentrations of P4 and E2 were evaluated by RIA after 24, 48, and 72 h of culture and values were corrected by tissue weight (10 mg). Morphological analysis of the explants was stained with hematoxylin and eosin. The total mRNA from GC-TC explants was purified and the expression of the following genes was estimated by RT-PCR: bovine 3 beta-hydroxysteroid dehydrogenase (HSD3B1), cholesterol side-chain cleavage cytochrome P450 (CYP11A1), 17|3-hydroxylase (CYP17), aromatase cytochrome P450 (CYP19), steroidogenic acute regulatory protein (StAR), follicle-stimulating hormone receptor (FSHr), and the housekeeping gene glyceraldehyde-3-phosphate dehydrogenase (GAPD) as internal control. The results were analyzed by two-way ANOVA followedby Bonferroni least-significant tests. Microscopic analyses showed that cells cultured in NDM lost their polyhedral shape and acquired a fibroblast-like form. Defined medium maintained GC morphology with low cytoplasm:nucleus ratio and GC-GC contact, similar to in vivocells. In NDM, the concentration of P4 increased as opposed to that of E2, which decreased after 48 h of culture. In DM, the concentrations of P4 and E2 were maintained in the first 48 h of culture. The level of P4 in NDM was higher than in DM during all periods tested. Our data show that CYP11A1 expression remains absent in NDM for follicles explants that initially did not express CYP11A1, whereas in DM the expression of this gene appears after 24, 48, or 72 h of culture, evidence that indicates rescue from atresia. It is important to notice that gene expression of steroidogenic enzymes in DM were higher than in NDM. Very low levels of CYP11A1 and CYP19 were observed in the NDM group. On the other hand, in the DM group there was a progressive increase of all the steroidogenic enzymes and FSHr, which reached a peak at 48 h of culture. In conclusion, our results suggest that DM showed a stimulating effect on steroidogenic activity of GC-TC co-culture similar to that observed in vivofor functional growing follicle, whereas in NDM the explants seemed to mimic luteinizing follicles. Grants from FAP-DF, Finatec, CNPq, and Capes. [ABSTRACT FROM AUTHOR]

FSH at low concentrations affect embryo production. In vitroculture conditions also affect embryo production and embryonic expression of genes and alter oocyte competence to produce embryos. The search for better and less variable culture conditions simulating those in vivohas led to the development of several systems of oocyte in vitromaturation culture. To compare the efficiency of the systems of MIV we utilized 4 groups: (1) TCM-199 control; (2) α-minimal essential medium (MEM); 3) α-MEM + 1 ng of FSH; 4) α-MEM+ 10 ng of FSH. The medium of Group 1 is non-defined by the presence of fetal calf serum (10%). Groups 2, 3, and 4 are defined and polyvinyl alcohol (1%) was used as a macromolecule. Porcine FSH (1 IU mg-1) was used at 1 and 10 ng mL-1and at 100 ng in defined and non-defined medium, respectively. Bovine ovaries were collected at an abbatoir. Oocytes (n= 1718) with homogeneous cytoplasm and with more than 3 layers of granulosa cells were used. Mature oocytes from the 4 treatments (11 replicates of each treatment) were inseminated with frozen-thawed, motile sperm separated by Percoll, using Sperm TALP HEPES medium. Presumptive zygotes with up to 2 or 3 layers of cumulus cells were cultured in 50-mL drops of SOF medium, supplemented with 10% FCS and 1 mg mL-1BSA under mineral oil in a humid 5% CO2atmosphere at 38.5°C after. Cleavage rate was evaluated 72 h post-insemination (hpi), and blastocyst rate was evaluated 168-192 hpi. Cleavage and blastocyst rates were calculated on the basis of number of presumptive zygotes. The expression of the following genes (Bax, Bcl-2, and conexin 43) was evaluated in blastocysts by RT-PCR. One-way ANOVA was used to compare blastocyst number. There was no difference in the proportion of embryos with more than 8 blastomeres in all groups tested, indicating that the rate of development during the first 72 hpi was similar for oocytes matured in chemically defined medium and for oocytes matured in medium containing serum. Bax is a pro-apoptotic marker and Bcl-2 an antiapoptotic marker. Connexin 43 (Cx43) may be a marker of embryo competence. Glyceraldehyde 3-phosphate dehydrogenase was used as internal control. The Bax gene was not expressed in any group. The Bcl-2 and Cx43 genes were expressed, mainly in the α-MEM 10. Although no differences were observed in blastocyst rate among the groups (30% to 40%), the strong expression of Bcl-2 and of Cx43 on the group containing 10 ng mL-1of FSH may indicate that FSH could improve embryo quality under defined conditions. The authors thank FAP-DF, CNPq, FUNPE, FINATEC, CAPES, and Biovitro Tecnologia de Embrioes Ltda, for laboratory assistance and grants, and Frigorifico Ponte Alta, Brasília-DF, for supplying bovine ovaries. [ABSTRACT FROM AUTHOR]