We find that the formation of MWC 656 (the first Be binary containing a black hole) involves a common envelope phase and a supernova explosion. This result supports the idea that a rapidly rotating ...Be star can emerge out of a common envelope phase, which is very intriguing because this evolutionary stage is thought to be too fast to lead to significant accretion and spin up of the B star. We predict ∼10–100 of B-BH binaries to currently reside in the Galactic disc, among which around 1/3 contain a Be star, but there is only a small chance to observe a system with parameters resembling MWC 656. If MWC 656 is representative of intrinsic Galactic Be-BH binary population, it may indicate that standard evolutionary theory needs to be revised. This would pose another evolutionary problem in understanding black hole (BH) binaries, with BH X-ray novae formation issue being the prime example. Future evolution of MWC 656 with an ∼5 M⊙ BH and with an ∼13 M⊙ main-sequence companion on an ∼60 d orbit may lead to the formation of a coalescing BH–NS (neutron star) system. The estimated Advanced LIGO/Virgo detection rate of such systems is up to ∼0.2 yr−1. This empirical estimate is a lower limit as it is obtained with only one particular evolutionary scenario, the MWC 656 binary. This is only a third such estimate available (after Cyg X-1 and Cyg X-3), and it lends additional support to the existence of so far undetected BH–NS binaries.
Purpose:
To assess the thickness of the retinal nerve fiber layer (RNFL), ganglion cell and inner plexus layer (GCIPL) and blood flow parameters in retrobulbar vessels, and to analyze correlations ...between these parameters in myopes.
Methods:
The study included forty myopic and 20 healthy eyes. Standard eye examination was supplemented with OCT of the optic nerve and macula (GCIPL, RNFL, RNFL in each quadrant and rim area of the optic nerve) and color Doppler imaging of retrobulbar arteries peak systolic and end-diastolic velocities, pulsatile index and resistance index (RI) in the ophthalmic (OA), central retinal (CRA), nasal posterior ciliary and temporal posterior ciliary arteries.
Results:
Significant correlations were found between blood flow parameters in the CRA, RNFL and GCIPL thickness, and axial length (AL) and spherical equivalent (SE). There were significant positive correlations between RNFL with PSV and EDV in the CRA and negative correlations between RNFL and RI in the CRA. GCIPL was positively correlated with PSV and EDV in the CRA. The decrease in RA was associated with reduced blood flow velocities in the CRA, TPCA and NPCA.
Conclusion:
The reduced retrobulbar blood flow in healthy young myopes is correlated with increasing AL and refractive value, and thinning of the RNFL and GCIPL. Reduction of the rim-area of the optic disc is associated with vascular and retinal circulatory disorders. These phenomena indicate the vascular basis of the described changes. To the best of our knowledge, this is the first study which correlates ocular circulation with retinal structure.
Vascular progenitor cells contribute to repair of injured vasculature. In this study, we aimed to investigate the role of bone marrow–derived cells in the intimal formation after arterial injury.
...Balloon injury of the femoral artery of wild-type mice was followed by local delivery of bone marrow–derived cells from GFP transgenic mice. The arteries were collected 1, 4, 7, and 14 days after injury and studied for morphology, localization, and phenotypes of delivered cells. Bone marrow–derived cells were present in the intima only at the early stages of arterial injury and expressed endothelial progenitor cell markers (CD31, CD34, and VEGFR-2). In the areas where intima was thicker, bone marrow–derived cells differentiated to intimal smooth muscle cells but they did not fuse with intimal cells. Delivery of CD34+ cells contributed to a 1.5-fold inhibition of intimal hyperplasia.
Bone marrow–derived endothelial cells differentiated but did not fuse with vascular smooth muscle cells at the early stages of intimal formation and contributed to intimal hyperplasia.
The single-mirror small-size telescope (SST-1M) is one of the three proposed designs for the small-size telescopes (SSTs) of the Cherenkov Telescope Array (CTA) project. The SST-1M will be equipped ...with a 4 m-diameter segmented reflector dish and an innovative fully digital camera based on silicon photo-multipliers. Since the SST sub-array will consist of up to 70 telescopes, the challenge is not only to build telescopes with excellent performance, but also to design them so that their components can be commissioned, assembled and tested by industry. In this paper we review the basic steps that led to the design concepts for the SST-1M camera and the ongoing realization of the first prototype, with focus on the innovative solutions adopted for the photodetector plane and the readout and trigger parts of the camera. In addition, we report on results of laboratory measurements on real scale elements that validate the camera design and show that it is capable of matching the CTA requirements of operating up to high moonlight background conditions.
This study measured the changes in bioactive compounds L-ascorbic acid (AA) and total phenolic (TP) compounds and antioxidant activity (measured in Trolox equivalents, TE) in six potato (Solanum ...tuberosum L.) varieties with yellow, light-yellow, and cream-coloured flesh after several different treatments. The experimental materials included raw tubers and both peeled and unpeeled tubers that had been boiled. Analyses were conducted immediately after harvest and after 3 months of storage at 5degreesC and 8degreesC. Flesh colour significantly affected the AA and TP contents in tubers. The difference in AA content was 0.195 mg * g.sup.-1 DM between cream- and yellow-coloured tubers and 0.086 mg * g.sup.-1 DM between cream and light-yellow tubers. Differences in TP contents between tubers with different flesh colours did not exceed 33%. Significant losses in AA were detected in yellow- and light-yellow-fleshed tubers that had been peeled and cooked after harvest (44 and 46%, respectively). Cooking peeled tubers significantly decreased the antioxidant activity in potatoes regardless of flesh colour and storage treatment. Unpeeled cooked tubers had significantly higher antioxidant activity than raw tubers after harvest. Irrespective of flesh colour, high linear correlations were found between (AA) * (TE) for cooked peeled tubers. A significant determination coefficient (R.sup.2) was observed between (TPs) * (TE) for raw and cooked unpeeled light-yellow and yellow-coloured tubers. The linear relationship between TPs and TE after cooking was significant for unpeeled tubers. The greatest matching of the model characteristics of the interdependence of features (phi.sup.2) was 75% for (AA) * (TE) and 80% for (TPs) * (TE). Keywords: antioxidant activity, ascorbic acid, phenolics, boiling, potato, storage
Nowadays, Hepatitis B X interacting protein (HBXIP) is an object of scientists’ interest worldwide. It is a protein with significant involvement in the development of malignant tumors like breast or ...ovarian cancer. One of the most important functions of HBXIP is the regulation of cell proliferation, which is related to the progression of a cell cycle. Many studies provide the growing number of evidence that HBXIP plays various important roles, including the regulation of a cell cycle through complexes with survivin, belonging to the inhibitors of apoptosis and interactions with transcriptional factors like STAT4, SP1, TFIID or E2F1. It also has the influence on the promotion of tumor angiogenesis thanks to the association with VEGF and FGF8. Another important role of HBXIP is a reprogramming of glucose metabolism to conditions favorable to growing cancerous cells due to regulating the activation of SCO2 and PDHA1. Furthermore, it impacts on the complement-dependent cytotoxicity, also, HBXIP affects on lipid metabolism through disturbing of metabolic pathways of FAS. According to recent studies, HBXIP can be used as a prognostic biomarker in many tumors, including cervical cancer, ovarian cancer, and esophageal squamous cell carcinoma thanks to the high expression of this protein noted exclusively in these tumor tissues. What is even more interesting, it significantly correlates with clinical attributes like metastasis to lymph nodes or grading and in some cases can potentially be used as the indicator of prognosis of treatment effectiveness. The paper is review through main functions of HBXIP and its possible applications.
Introduction: Expression of Epo, a glycoprotein secreted by the fetal liver and the adult kidney in response to cellular hypoxia and its receptor have been described in human solid tumors, such as ...colon and breast cancer. Purpose: Since activation of Epo-EpoR signaling pathway in erythroid progenitor and precursor cells leads to promotion of proliferation and differentiation or prevention of programmed cell death through Bcl-xl and Bcl-2 it was of interest to investigate expression of Epo, EpoR, apoptosis regulator – Bax and marker of proliferating cells - Ki-67 and assess correlation between them, with regard to clinicopathological variables of colorectal cancer. Materials and methods: The correlations between expression of Epo, EpoR, Bax and Ki-67 in colorectal cancer were analyzed in regard to patient age, sex, primary localization, histopathological type, grading, staging and lymph node invasion. Statistical analyses were performed by using the Spearman rank correlation test applying a significance level of p<0,05. Results: Correlation between Bax and EpoR is positive and statistically significant at all groups of patients except group pT1+pT2. Positive correlation between Bax and Epo is statistically significant at following groups of patients: all patients, age 60, age >60, male, female , primary localization in rectum, primary localization in colon, adenocarcinoma, G2, G3. Statistical analysis revealed no significant correlations between expression of neither Ki-67 with Epo nor Ki-67 with EpoR in all groups of patients. Conclusions: Epo seems to be a pleiotropic cytokine, which can exert its biological effect on several cell types, including neoplastic cells. The effect of Epo-EpoR signaling can differ in various cells and conditions.
The single mirror Small Size Telescope (SST-1M) is one of the proposed designs for the smallest type of telescopes, SSTs that will compose the Cherenkov Telescope Array (CTA).
The SST-1M camera will ...use Silicon PhotoMultipliers (SiPM) which are nowadays commonly used in High Energy Physics experiments and many imaging applications. However the unique pixel shape and size have required a dedicated development by the University of Geneva and Hamamatsu. The resulting sensor has a surface of ∼94mm2 and a total capacitance of ∼3.4nF. These unique characteristics, combined with the stringent requirements of the CTA project on timing and charge resolution have led the University of Geneva to develop custom front-end electronics.
The preamplifier stage has been tailored in order to optimize the signal shape using measurement campaigns and electronic simulation of the sensor. A dedicated trans-impedance pre-amplifier topology is used resulting in a power consumption of 400mW per pixel and a pulse width <30ns. The measurements that have led to the choice of the different components and the resulting performance are detailed in this paper.
The slow control electronics was designed to provide the bias voltage with 6.7mV precision and to correct for temperature variation with a forward feedback compensation with 0.17°C resolution. It is fully configurable and can be monitored using CANbus interface. The architecture and the characterization of the various elements are presented.
The Cherenkov Telescope Array (CTA), the next generation very high energy gamma-rays observatory, will consist of three types of telescopes: large (LST), medium (MST) and small (SST) size telescopes. ...The SSTs are dedicated to the observation of gamma-rays with energy between a few TeV and a few hundreds of TeV. The SST array is expected to have 70 telescopes of different designs.
The single-mirror small size telescope (SST-1M) is one of the proposed telescope designs under consideration for the SST array. It will be equipped with a 4m diameter segmented mirror dish and with an innovative camera based on silicon photomultipliers (SiPMs).
The challenge is not only to build a telescope with exceptional performance but to do it foreseeing its mass production. To address both of these challenges, the camera adopts innovative solutions both for the optical system and readout.
The Photo-Detection Plane (PDP) of the camera is composed of 1296pixels, each made of a hollow, hexagonal light guide coupled to a hexagonal SiPM designed by the University of Geneva and Hamamatsu. As no commercial ASIC would satisfy the CTA requirements when coupled to such a large sensor, dedicated preamplifier electronics have been designed. The readout electronics also use an innovative approach in gamma-ray astronomy by adopting a fully digital approach. All signals coming from the PDP are digitized in a 250MHz Fast ADC and stored in ring buffers waiting for a trigger decision to send them to the pre-processing server where calibration and higher level triggers will decide whether the data are stored. The latest generation of FPGAs is used to achieve high data rates and also to exploit all the flexibility of the system. As an example each event can be flagged according to its trigger pattern. All of these features have been demonstrated in laboratory measurements on realistic elements and the results of these measurements will be presented in this contribution.
Understanding the full diet of natural enemies is necessary for evaluating their role as biocontrol agents, because many enemy species do not only feed on pests but also on other natural enemies. ...Such intraguild predation can compromise pest control if the consumed enemies are actually better for pest control than their predators. In this study, we used gut metabarcoding to quantify diets of all common arachnid species in Swedish and Spanish apple orchards. For this purpose, we designed new primers that reduce amplification of arachnid predators while retaining high amplification of all prey groups. Results suggest that most arachnids consume a large range of putative pest species on apple but also a high proportion of other natural enemies, where the latter constitute almost a third of all prey sequences. Intraguild predation also varied between regions, with a larger content of heteropteran bugs in arachnid guts from Spanish orchards, but not between orchard types. There was also a tendency for cursorial spiders to have more intraguild prey in the gut than web spiders. Two groups that may be overlooked as important biocontrol agents in apple orchards seem to be theridiid web spiders and opilionids, where the latter had several small-bodied pest species in the gut. These results thus provide important guidance for what arachnid groups should be targets of management actions, even though additional information is needed to quantify all direct and indirect interactions occurring in the complex arthropod food webs in fruit orchards.
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