A SAURON study of dwarf elliptical galaxies in the Virgo Cluster

Dwarf elliptical galaxies are the most common galaxy type in nearby galaxy clusters, yet they remain relatively poorly studied objects and many of their basic properties have yet to be quantified. In this contribution we present the preliminary results of a study of 4 Virgo and 1 field galaxy obtained with the SAURON integral field unit on the William Herschel Telescope (La Palma). While traditional long-slit observations are likely to miss more complicated kinematic features, with SAURON we are able to study both kinematics and stellar populations in two dimensions, obtaining a much more detailed view of the mass distribution and star formation histories.Comment: 2 pages, 1 figure; to appear in the proceedings of the conference "A Universe of dwarf galaxies" (Lyon, June 14-18, 2010

Analysis of Gear Wheel-shaft Joint Characterized by Comparable Pitch Diameter and Mounting Diameter

This paper presents the design procedure for a gear wheel-shaft direct frictional joint. The small difference between the operating pitch diameter of the gear and the mounting diameter of the frictional joint is the key feature of the connection. The contact surface of the frictional joint must be placed outside the bottom land of the gear, and the geometry of the joint is limited to the specific type of solutions.The strength analysis is based on the relation between the torque and statistical load intensity of the gear transmission. Several dimensionless parameters are introduced to simplify the calculations. Stress-strain verifying analysis with respect to combined loading, the condition of appropriate load-carrying capacity of the frictional joint and the fatigue strength of the shaft are applied to obtain the relations between the dimensions of the joint and other parameters. The final engineering solution may then be suggested. The approach is illustrated by a numerical example.The proposed procedure can be useful in design projects for small, high-powered modern reducers and new-generation geared motors, in particular when manufactured in various series of types

Hubble Space Telescope study of resolved red giant stars in the outer halos of nearby dwarf starburst galaxies

[abridged] Aims. We observed the outer parts of NGC 1569 and NGC 4449, two of the closest and strongest dwarf starburst galaxies in the local universe, to characterize their stellar density and populations, and obtain new insights into the structure, formation, and evolution of starburst galaxies and galaxy halos. Methods. We obtained HST/WFPC2 images between 5 and 8 scale radii from the center, along the intermediate and minor axes. We performed point-source photometry to determine color magnitude diagrams of I vs. V-I. We compared the results at different radii, including also our prior HST/ACS results for more centrally located fields. Results. We detect stars in the RGB and TP-AGB (carbon star) phases in all outer fields, but not younger stars such as those present at smaller radii. The RGB star density profile is well fit by either a de Vaucouleurs profile or a power-law profile, but has more stars at large radii than a single exponential. To within the uncertainties, there are no radial gradients in the RGB color or carbon-to-RGB-star ratio at large radii. Conclusions. The galaxies have faint outer stellar envelopes that are not tidally truncated within the range of radii addressed by our study. The density profiles suggest that these are not outward extensions of the inner disks, but are instead distinct stellar halos. This agrees with other work on galaxies of similar morphology. The presence of such halos is consistent with predictions of hierarchical galaxy formation scenarios. The halos consist of intermediate-age/old stars, confirming the results of other studies that have shown the starburst phenomenon to be very centrally concentrated. There is no evidence for stellar-population age/metallicity gradients within the halos themselves.Comment: 13 pages, 13 figures and 2 tables. Accepted for publication in A&

Diversity of vegetation dominated by selected grass species on coal-mine spoil heaps in terms of reclamation of post-industrial areas

Published by Polish Society of Ecological Engineering (PTIE). This is an open access article available under a Creative Commons licence. The published version can be accessed at the following link on the publisher’s website: https://doi.org/10.12911/22998993/93870© 2018, Polish Society of Ecological Engineering (PTIE). Grasses have a considerable potential for the adaptation to various, often extreme, habitat conditions. The aim of the work was to present the vegetation diversity of the coal-mine spoil heaps with the dominant share of grasses and to identify the main factors responsible for this diversity in the aspect of post-industrial land reclamation. The communities differ in reference to the species preferences to light, moisture, soil fertility and reaction, which is reflected in the wide variety of microhabitats in the area. It was shown that the increase in the abundance of certain grass species, including Calamagrostis epigejos, Festuca rubra, Festuca arundinacea, Phragmites australis, has a significant negative impact on the species richness, species diversity and the uniformity of distribution of species of the plant community. Preliminary analyses revealed that on post-mining waste, the biomass production of the dominant species is negatively correlated with biodiversity. The knowledge about the biology and ecology of grass species, as well as on the assembly rules may be used in the reclamation of degraded areas. Gaining the knowledge about the vegetation diversity of the coal-mine spoil heaps with the dominant share of grasses can be useful in planning the reclamation works, taking into account natural processes, which leads to the creation of a permanent vegetation cover at a given site, protecting it against water or wind erosion. In the future these areas may provide a number of important ecosystem services.Published versio

Antlia Dwarf Galaxy: Distance, quantitative morphology and recent formation history via statistical field correction

We apply a statistical field correction technique originally designed to determine membership of high redshift galaxy clusters to Hubble Space Telescope imaging of the Antlia Dwarf Galaxy; a galaxy at the very edge of the Local Group. Using the tip of the red giant branch standard candle method coupled with a simple Sobel edge detection filter we find a new distance to Antlia of 1.31 +/- 0.03 Mpc. For the first time for a Local Group Member, we compute the concentration, asymmetry and clumpiness (CAS) quantitative morphology parameters for Antlia from the distribution of resolved stars in the HST/ACS field, corrected with a new method for contaminants and complement these parameters with the Gini coefficient (G) and the second order moment of the brightest 20 per cent of the flux (M_20). We show that it is a classic dwarf elliptical (C = 2.0, A = 0.063, S = 0.077, G = 0.39 and M_20 = -1.17 in the F814W band), but has an appreciable blue stellar population at its core, confirming on-going star-formation. The values of asymmetry and clumpiness, as well as Gini and M_20 are consistent with an undisturbed galaxy. Although our analysis suggests that Antlia may not be tidally influenced by NGC 3109 it does not necessarily preclude such interaction.Comment: Accepted for publication in MNRA

A patient presenting with a perivascular epithelioid cell tumor in the broad ligament: a case report

<p>Abstract</p> <p>Introduction</p> <p>Perivascular epithelioid cell tumors are a family of rare mesenchymal tumors composed of histologically and immunohistochemically distinctive perivascular epithelioid cells. They can originate in any visceral organ or soft tissue and include a range of lesions such as angiomyolipoma, clear cell 'sugar' tumor of the lung, lymphangioleiomyomatosis and clear cell myomelanocytic tumors of the falciparum ligament/ligament teres. Due to their rarity and varied sites and presentation, management of these tumors remains highly challenging.</p> <p>Case Presentation</p> <p>A 46-year-old para 2 Caucasian woman initially presented to the general surgeons at our hospital in North West London with abdominal pain. Laparoscopy revealed a right broad ligament hematoma, which was thought to be iatrogenic in origin, from insertion of the Veress needle at the time of surgery, and was managed conservatively. Upon her re-presentation two months later with severe pain, ultrasound scanning revealed the hematoma had increased in size and she underwent a total abdominal hysterectomy and bilateral salpingo-oophorectomy. Histology results from necrotic tissue from the hematoma led to a diagnosis of perivascular epithelioid cell tumor. She was then referred to a tertiary oncology center, where she underwent several further operations in an attempt to debulk the tumor for symptomatic relief of her pain, with limited success. She is now taking the immunosuppressive drug sirolimus, which has produced a modest reduction in tumor size. She is now 47 months on from initial presentation.</p> <p>Conclusions</p> <p>A literature search has revealed only six other case reports of broad ligament perivascular epithelioid cell tumors, with varied presentations and management. The longest duration of follow-up was 21 months. Only five other cases of perivascular epithelioid cell tumor managed with sirolimus have been reported. We therefore feel that this report highlights some of the difficulties in diagnosing perivascular epithelioid cell tumors, and sheds light on management strategies for a very rare gynecological tumor in addition to sharing our experience in the use of sirolimus in its treatment.</p

Graphene on quartz modified with rhenium oxide as a semitransparent electrode for organic electronic

Our research shows that commercially available graphene on quartz modified with rhenium oxide meets the requirements for its use as a conductive and transparent anode in optoelectronic devices. The cluster growth of rhenium oxide enables an increase in the work function of graphene by 1.3 eV up to 5.2 eV, which guarantees an appropriate adjustment to the energy levels of the organic semiconductors used in OLED devices.Comment: 8 pages, 3 figure

Evolution of Microstructure and Texture during Warm Rolling Of a Duplex Steel

The effect of warm rolling on the evolution of microstructure and texture in a duplex stainless steel (DSS) was investigated. For this purpose, a DSS steel was warm rolled up to 90 pct reduction in thickness at 498 K, 698 K, and 898 K (225 °C, 425 °C, and 625 °C). The microstructure with an alternate arrangement of deformed ferrite and austenite bands was observed after warm rolling; however, the microstructure after 90 pct warm rolling at 498 K and 898 K (225 °C and 625 °C) was more lamellar and uniform as compared to the rather fragmented and inhomogeneous structure observed after 90 pct warm rolling at 698 K (425 °C). The texture of ferrite in warm-rolled DSS was characterized by the presence of the RD (〈011〉//RD) and ND (〈111〉//ND) fibers. However, the texture of ferrite in DSS warm rolled at 698 K (425 °C) was distinctly different having much higher fraction of the RD-fiber components than that of the ND-fiber components. The texture and microstructural differences in ferrite in DSS warm rolled at different temperatures could be explained by the interaction of carbon atoms with dislocations. In contrast, the austenite in DSS warm rolled at different temperatures consistently showed pure metal- or copper-type deformation texture which was attributed to the increase in stacking fault energy at the warm-rolling temperatures. It was concluded that the evolution of microstructure and texture of the two constituent phases in DSS was greatly affected by the temperature of warm rolling, but not significantly by the presence of the other phas

Soft tissue sarcoma - diagnosis and treatment

W ciągu ostatnich kilkunastu lat osiągnięto znaczący postęp w leczeniu mięsaków tkanek miękkich - nie tylko ogniska pierwotnego, ale również wznów miejscowych i przerzutów. Podstawową metodą jest leczenie chirurgiczne, a wprowadzenie zasady skojarzonego postępowania, czyli standardowego łączenia chirurgii z radioterapią i niekiedy chemioterapią oraz rehabilitacji w wyspecjalizowanych ośrodkach znamiennie zwiększyło szansę na ograniczenie zasięgu operacji, całkowite wyleczenie chorego lub uzyskanie długoletniego przeżycia. Współczesne leczenie skojarzone oraz stosowanie metod rekonstrukcyjnych pozwala u większości chorych na mięsaki tkanek miękkich o lokalizacji kończynowych na oszczędzenie kończyny. W porównaniu z latami 60.-70., kiedy amputację wykonywano u około 50% chorych, obecnie w ośrodkach referencyjnych odsetek ten nie przekracza 10%. Ogólnie obserwuje się powolny, ale stały wzrost odsetka chorych na mięsaki tkanek miękkich z wieloletnimi przeżyciami. Wskaźnik 5-letnich przeżyć całkowitych chorych na mięsaki tkanek miękkich zlokalizowane w obrębie kończyn wynosi obecnie 55-78%. W przypadku rozpoznania przerzutów długość okresu przeżycia jest jednak nadal zła i wynosi średnio około 1 roku. Korzystnych wyników miejscowych leczenia mięsaków można spodziewać się tylko w przypadku planowego (tzn. po wcześniejszej biopsji) całkowitego wycięcia mięsaka w mikroskopowo wolnych od nowotworu granicach (tzw. resekcja R0). Po przeprowadzeniu prawidłowego postępowania diagnostycznego u większości chorych poddawanych radykalnej operacji konieczne jest zastosowanie uzupełniającej radioterapii, wielotygodniowej rehabilitacji i kontynuowanie badań kontrolnych w tym samym ośrodku przez minimum 5 lat. Postęp wiąże się z wprowadzeniem do praktyki klinicznej leków o celowanym działaniu związanym z molekularnymi lub genetycznymi zaburzeniami w komórkach, które uczestniczą w etiopatogenezie tych nowotworów. Ze względu na rzadkie występowanie mięsaków oraz konieczność skojarzonego postępowania najważniejsze jest prowadzenie diagnostyki i terapii już od początku w ramach wielodyscyplinarnego zespołu w ośrodku onkologicznym o odpowiednim doświadczeniu i zapleczu diagnostycznym.Significant progress in the treatment of soft tissue sarcoma (STS), both primary tumor and local recurrences/ metastatic disease, has been achieved in recent years. Surgery is essential modality, but the use of combined treatment (standard combination of surgery with adjuvant radiotherapy, chemotherapy in selected cases and perioperative rehabilitation) in highly-experienced centers increased possibility of cure and limitations of extent of local surgery. Current combined therapy together with the use of reconstructive methods allows for limb-sparing surgery in majority of soft tissue sarcoma patients (amputation in 10% of cases as compared to approximately 50% in the 1960-70s). The slow, but constant, increase of rate of soft tissue sarcoma patients with long-term survival has been observed. Contemporary 5-year overall survival rate in patients with extremity soft tissue sarcomas is 55-78%. In case of diagnosis of metastatic disease the prognosis is still poor (survival of approximately 1 year). Good results of local therapy may be expected only after planned (e.g., after preoperative biopsy - tru-cut or incisional) radical surgical excision of primary tumor with pathologically negative margins (R0 resection). Following appropriate diagnostic check-up, adjuvant radiotherapy is necessary in the majority of patients treated with radical surgery need, as well as long-term rehabilitation and follow-up examinations in treating center are needed for at least 5 years. The progress is due to the introductionof targeted therapy acting on molecular or genetic cellular disturbances detected during studies on etiopathogenetic mechanisms of sarcoma subtypes. In view of rarity of sarcomas and necessity of multidisciplinary therapy, the crucial issue is that management of these tumors should be hold in experienced oncological sarcoma centers