The impact of realistic models of mass segregation on the event rate of extreme-mass ratio inspirals and cusp re-growth

One of the most interesting sources of gravitational waves (GWs) for LISA is the inspiral of compact objects on to a massive black hole (MBH), commonly referred to as an "extreme-mass ratio inspiral" (EMRI). The small object, typically a stellar black hole (bh), emits significant amounts of GW along each orbit in the detector bandwidth. The slowly, adiabatic inspiral of these sources will allow us to map space-time around MBHs in detail, as well as to test our current conception of gravitation in the strong regime. The event rate of this kind of source has been addressed many times in the literature and the numbers reported fluctuate by orders of magnitude. On the other hand, recent observations of the Galactic center revealed a dearth of giant stars inside the inner parsec relative to the numbers theoretically expected for a fully relaxed stellar cusp. The possibility of unrelaxed nuclei (or, equivalently, with no or only a very shallow cusp) adds substantial uncertainty to the estimates. Having this timely question in mind, we run a significant number of direct-summation $N-$body simulations with up to half a million particles to calibrate a much faster orbit-averaged Fokker-Planck code. We then investigate the regime of strong mass segregation (SMS) for models with two different stellar mass components. We show that, under quite generic initial conditions, the time required for the growth of a relaxed, mass segregated stellar cusp is shorter than a Hubble time for MBHs with $M_\bullet \lesssim 5 \times 10^6 M_\odot$ (i.e. nuclei in the range of LISA). SMS has a significant impact boosting the EMRI rates by a factor of $\sim 10$ for our fiducial models of Milky Way type galactic nuclei.Comment: Accepted by CQG, minor changes, a bit expande

Observação introspectiva de uma tarefa do voleibol em ambiente escolar

Parece ser já um lugar comum dizer-se que os professores de educação física e os treinadores desportivos tentam ajudar os praticantes (alunos e atletas) no sentido de melhorar as suas prestações e que, para atingirem tal objectivo, têm de observar criteriosamente as suas execuções motoras de modo a poderem fornecer "feedbacks" apropriados que as facilitem e melhorem. Por outro lado há uma constante necessidade de controlar o envolvimento onde estão inseridos de forma a permitir-lhes uma eficaz intervenção pedagógica. Esse controle é efectuado pela sua competência de observação. Estas são as razões primordiais que nos levam a dizer que a observação é uma tarefa inerente ao ensino e ao treino das habilidades físicas e desportivas, tendo em conta a sua necessidade para supervisionar os mais diversificados aspectos do comportamento dos seus alunos (atenção, disciplina, comportamentos apropriados e inapropriados, fora da tarefa, etc.), como também o desenvolvimento dos comportamentos técnicos, possibilitando corrigir erros de execução e, consequentemente, aperfeiçoá-los

Vombat: An Open Source Tool for Creating Stratigraphic Logs from Virtual Outcrops

An open source tool, Vombat , is presented that is designed to operate on Virtual Outcrop Models of sedimentary rocks, with the specific aim of assisting the stratigraphic analysis and interpretation. Vombat makes it possible to estimate the average attitude of the bedding and to create one or more attitude-aligned stratigraphic reference frames. This allows Vombat to extract continuous stratigraphic logs of any property associated with the point clouds (e.g. the lidar intensity or RGB color). Stratigraphic logs produced by Vombat can be compared and correlated to typical outcrop logs and petrophysical logs obtained from boreholes (e.g. gamma ray logs) and can provide information about the lithological variations in a stratigraphic succession. Furthermore, Vombat stratigraphic reference frames can be used to associate a stratigraphic position (a depth in the stratigraphic column) to any observation made on the outcrop, allowing visualization in 3D (on the virtual outcrop model) and 1D (on a stratigraphic column) for any collected data. All the geological objects created in the virtual environment can then be saved. The tool has been developed to be user-friendly and is constituted by a dynamically loaded plugin for the open source software CloudCompare

Total phallic construction techniques in transgender men: An updated narrative review

From 2012, the World Professional Association Transgender Health defined a structured therapeutic path and standards of care for transgender patients undergoing genital gender affirming surgery (GGAS). The main goal of GGAS in transgender males is to provide patients with an aesthetically appealing appearance of the neophallus that should allow standing micturition and enabling penetrative intercourse along with erogenous and tactile sensitivity. The optimal procedure should be safe, reproducible and performed in the fewest number of surgical stages. The ideal technique for total phallic construction (TPC) has not yet been demonstrated; TPC remains challenging and, from a functional point of view, it is also make more demanding as yet there are no perfect replacement materials for erectile and urethral tissues. Several procedures and different type of flaps (pedicled and free-flaps) have been proposed and investigated over time to address TPC with significant advances over the years especially after microsurgical procedures introduction. Due to its high complexity TPC is not free from complications. Local tissue ischaemic complications, complete and partial flap loss, donor site morbidity and urethral complications (fistulae and strictures) are reported. This narrative review aims to provide the readers with a contemporary overview of surgical procedures for TPC in transgender males focusing on key surgical steps, as well as surgical and functional outcomes

Using Pilot Systems to Execute Many Task Workloads on Supercomputers

High performance computing systems have historically been designed to support applications comprised of mostly monolithic, single-job workloads. Pilot systems decouple workload specification, resource selection, and task execution via job placeholders and late-binding. Pilot systems help to satisfy the resource requirements of workloads comprised of multiple tasks. RADICAL-Pilot (RP) is a modular and extensible Python-based pilot system. In this paper we describe RP's design, architecture and implementation, and characterize its performance. RP is capable of spawning more than 100 tasks/second and supports the steady-state execution of up to 16K concurrent tasks. RP can be used stand-alone, as well as integrated with other application-level tools as a runtime system

Exploitation of filamentous and picoplanktonic cyanobacteria for cosmetic applications: potential to improve skin structure and preserve dermal matrix components

The use of natural products in skin care formulations gained interest as a concern for modern societies. The undesirable side effects of synthetic compounds, as well as the associated environmental hazards, have driven investigation on photosynthetic organisms as sustainable sources of effective and environmentally friendly ingredients. The use of natural extracts in cosmetics has been highlighted and, along with plants and algae, cyanobacteria have come into focus. Due to their low culture demands, high grow rates and ability to produce a wide variability of bioactive metabolites, cyanobacteria emerged as an economic and sustainable base for the cosmetic industry. In this study, we evaluated the potential of ethanol extracts of picocyanobacteria strains of the genera Cyanobium and Synechocystis and filamentous strains of the genera Nodosilinea, Phormidium and Tychonema for skin applications, with focus in the field of anti-aging. The extracts were analyzed for their pigment profile, phenolic content, antioxidant potential, cytotoxicity against keratinocytes (HaCat), fibroblasts (3T3L1), endothelial cells (hCMEC/D3) and capacity to inhibit hyaluronidase (HAase). The total carotenoid content ranged from 118.69 to 383.89 μg g−1 of dry biomass, and the total phenolic content from 1.07 to 2.45 mg GAE g−1. Identified carotenoids consisted of zeaxanthin, lutein, canthaxanthin, echinenone and β-carotene, with zeaxanthin and lutein being the most representative (49.82 and 79.08 μg g−1, respectively). The highest antioxidant potential was found for Phormidium sp. LEGE 05292 and Tychonema sp. LEGE 07196 for superoxide anion radical (O2•−) scavenging (IC50 of 822.70 and 924 μg mL−1, respectively). Low or no cytotoxicity were registered. Regarding HAase inhibition, Tychonema sp. LEGE 07196 and Cyanobium sp. LEGE 07175 showed the best IC50 (182.74 and 208.36 μg mL−1, respectively). In addition, an increase in fibroblast proliferation was registered with these same strains. From this work, the ethanol extracts of the species Tychonema sp. and Cyanobium sp. are particularly interesting for their potential application in anti-aging formulations, once they stimulated fibroblast proliferation and inhibit hyaluronic acid digestion.This work was done in the framework of the projects: BLUEHUMAN-BLUE biotechnology as a road for innovation on HUMAN’s health aiming smart growth in Atlantic Area-EAPA_151/2016 of the Interreg Atlantic Area Programme funded by the European Regional Development Fund; EnhanceMicroAlgae - High added-value industrial opportunities for microalgae in the Atlantic Area (EAPA_338/2016) of the Interreg Atlantic Area Programme funded by the European Regional Development Fund; ALGAVALOR - MicroALGAs: integrated production and valorization of biomass and its various applications - SI I&DT no. 352234-supported by the PORTUGAL 2020 through the European Regional Development Fund; and supported by the FCT Projects UIDB/04423/2020 and UIDP/04423/2020. The authors acknowledge the support and the use of resources of EMBRC-ERIC, specifically of the Portuguese infrastructure node of the European Marine Biological Resource Centre (EMBRC-PT) CIIMAR–PINFRA/22121/2016–ALG-01-0145-FEDER-022121, financed by the European Regional Development Fund (ERDF) through COMPETE2020-Operational Programme for Competitiveness and Internationalisation (POCI) and national funds through FCT/MCTES

Antiproliferative effects of the natural oxadiazine nocuolin A are associated with impairment of mitochondrial oxidative phosphorylation

Natural products are interesting sources for drug discovery. The natural product oxadiazine Nocuolin A (NocA) was previously isolated from the cyanobacterial strain Nodularia sp. LEGE 06071 and here we examined its cytotoxic effects against different strains of the colon cancer cell line HCT116 and the immortalized epithelial cell line hTERT RPE-1. NocA was cytotoxic against colon cancer cells and immortalized cells under conditions of exponential growth but was only weakly active against non-proliferating immortalized cells. NocA induced apoptosis by mechanism(s) resistant to overexpression of BCL family members. Interestingly, NocA affected viability and induced apoptosis of HCT116 cells grown as multicellular spheroids. Analysis of transcriptome profiles did not match signatures to any known compounds in CMap but indicated stress responses and induction of cell starvation. Evidence for autophagy was observed, and a decrease in various mitochondrial respiration parameter within 1h of treatment. These results are consistent with previous findings showing that nutritionally compromised cells in spheroids are sensitive to impairment of mitochondrial energy production due to limited metabolic plasticity. We conclude that the antiproliferative effects of NocA are associated with effects on mitochondrial oxidative phosphorylation.This research was supported by the Structured Program of R&D&I INNOVMAR - Innovation and Sustainability in the Management and Exploitation of Marine Resources (reference NORTE-01-0145-FEDER-000035, Research Line NOVELMAR), funded by the Northern Regional Operational Program (NORTE2020) through the European Regional Development Fund (ERDF). The project was additionally supported the project CYANCAN - Uncovering the cyanobacterial chemical diversity: the search for novel anticancer compounds (reference PTDC/MEDQUI/30944/2017) co-financed by NORTE 2020, Portugal 2020, and the European Union through the ERDF, and by Foundation for Science and Technology through national funds. RU was supported by the FCT postdoc grant SFRH/BPD/112287/2015 and MS by the FCT PhD grant SFRH/BD/108314/2015