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The Euglenophyta include four genera of Euglena-like cells enclosed in a lorica. Two of these genera, Trachelomonas and Strombomonas, are free swimming. These taxa have been differentiated and classified at the generic and species level based primarily on the morphology of their lorica. Numerous SEM studies have been conducted, yet few, if any, TEM descriptions exist, especially for Strombomonas. This study describes both the outer lorica and internal ultrastructure for Strombomonas sp. isolated from a fresh water pond in New Jersey. Additionally, we describe the release of daughter cells from the lorica following cell division. Two cells were observed within a single Strombomonas lorica following cytokinesis. When exposed to the light of the microscope, one or both of the cells emerged through the neck of the lorica. The released cells could easily be mistaken for Euglena species. [ABSTRACT FROM AUTHOR]

An 11-year-old castrated male Persian cat was admitted to the veterinary clinic showing signs of lethargy, lack of appetite, laboured breathing, dyspnoea, and cyanosis. The echocardiogram showed a large amount of pleural effusion, fibrin, and a mass measuring 1.89 cm in diameter adhered to the parietal pericardium. Upon necropsy, several nodules were observed on the pericardium sac and pleura. Histological evaluation of the nodules and mediastinal lymph node revealed the presence of neoplastic cells of epithelial and mesenchymal origin. Immunolabelling was positive for both cytokeratin AE1/AE3 and vimentin in the primary tumour and in the mediastinal lymph node. In the present report, immunohistochemical analysis supported the diagnosis that had been obtained based on clinical signs, histopathological examination, and echocardiogram. [ABSTRACT FROM AUTHOR]

Context. In the last decade, astronomers have found a new type of supernova called superluminous supernovae (SLSNe) due to their high peak luminosity and long light-curves. These hydrogen-free explosions (SLSNe-I) can be seen to z ∼ 4 and therefore, offer the possibility of probing the distant Universe. Aims. We aim to investigate the possibility of detecting SLSNe-I using ESA’s Euclid satellite, scheduled for launch in 2020. In particular, we study the Euclid Deep Survey (EDS) which will provide a unique combination of area, depth and cadence over the mission. Methods. We estimated the redshift distribution of Euclid SLSNe-I using the latest information on their rates and spectral energy distribution, as well as known Euclid instrument and survey parameters, including the cadence and depth of the EDS. To estimate the uncertainties, we calculated their distribution with two different set-ups, namely optimistic and pessimistic, adopting different star formation densities and rates. We also applied a standardization method to the peak magnitudes to create a simulated Hubble diagram to explore possible cosmological constraints. Results. We show that Euclid should detect approximately 140 high-quality SLSNe-I to z ∼ 3.5 over the first five years of the mission (with an additional 70 if we lower our photometric classification criteria). This sample could revolutionize the study of SLSNe-I at z > 1 and open up their use as probes of star-formation rates, galaxy populations, the interstellar and intergalactic medium. In addition, a sample of such SLSNe-I could improve constraints on a time-dependent dark energy equation-of-state, namely w(a), when combined with local SLSNe-I and the expected SN Ia sample from the Dark Energy Survey. Conclusions. We show that Euclid will observe hundreds of SLSNe-I for free. These luminous transients will be in the Euclid data-stream and we should prepare now to identify them as they offer a new probe of the high-redshift Universe for both astrophysics and cosmology. [ABSTRACT FROM AUTHOR]

Supernova remnants (SNRs) are among the most important targets for γ -ray observatories. Being prominent non-thermal sources, they are very likely responsible for the acceleration of the bulk of Galactic cosmic rays (CRs). To firmly establish the SNR paradigm for the origin of cosmic rays, it should be confirmed that protons are indeed accelerated in, and released from, SNRs with the appropriate flux and spectrum. This can be done by detailed theoretical models which account for microphysics of acceleration and various radiation processes of hadrons and leptons. The current generation of Cherenkov telescopes has insufficient sensitivity to constrain theoretical models. A new facility, the Cherenkov Telescope Array (CTA), will have superior capabilities and may finally resolve this long standing issue of high-energy astrophysics. We want to assess the capabilities of CTA to reveal the physics of various types of SNRs in the initial 2000 years of their evolution. During this time, the efficiency to accelerate cosmic rays is highest. We perform time-dependent simulations of the hydrodynamics, the magnetic fields, the cosmic-ray acceleration, and the non-thermal emission for type Ia, Ic and IIP SNRs. We calculate the CTA response to the γ -ray emission from these SNRs for various ages and distances, and we perform a realistic analysis of the simulated data. We derive distance limits for the detectability and resolvability of these SNR types at several ages. We test the ability of CTA to reconstruct their morphological and spectral parameters as a function of their distance. Finally, we estimate how well CTA data will constrain the theoretical models. [ABSTRACT FROM AUTHOR]

A 12-year-old male Maltese dog was presented with a history of shivering episodes. Radiographs revealed a mass in the left kidney that was histopathologically classified as a renal cell carcinoma. After nephrectomy, pelvic limbs became paralyzed. Spinal cord and lung metastases were detected via histopathological examination and confirmed by immunohistochemistry. Both pan-cytoketatin and Ki67 assays tested positive in the kidney, lung, and spinal cord. Interestingly, COX- 2 had mild immunoreactivity in the kidney, but its labeling was intense in the spinal cord and lung. Though seemingly rare, the spinal cord may possibly be a focus point for metastasis of renal cell carcinomas. Because symptoms can easily be misunderstood, late diagnoses would not be uncommon and may hinder clinical management of the disease. [ABSTRACT FROM AUTHOR]

Domestic cats are invaluable research models for the study of hereditary diseases that affect both cats and humans. By necessity, most cat models are maintained as living populations; however, semen and embryo cryopreservation could provide a cost-effective alternative for model conservation if viable offspring can be readily produced with assisted reproductive techniques such as IVF, embryo transfer (ET) and AI. In our earlier research, semen and IVF-derived embryos representing 24 cat models at 7 veterinary/medical schools were frozen for liquid nitrogen storage. Our objectives in this study were to (1) assess the application of assisted reproduction using frozen semen or embryos for producing pregnancies and viable kittens in several cat models and (2) provide our university collaborators with rederived model offspring. Five cat models (i.e. spinal muscular atrophy, SMA; porphyria, POR; Chediak-Higashi syndrome, CHS; progressive retinal atrophy, PRA; and hypertrophic cardiomyopathy, HCM) were selected for propagation based on investigator research needs. For 3 models (SMA, POR and CHS), semen from affected males, frozen as pellets in Test Egg Yolk medium (with 4% glycerol), was thawed and used to inseminate (5 × 105 motile sperm mL-1) oocytes from eCG/hCG-treated queens. Resulting embryos (2- to 8-cell stage) were transferred laparoscopically (3-5 embryos/recipient) into the oviducts of anestrual queens synchronized with eCG/pLH. For PRA, IVF embryos from affected cats were frozen in 1.5 M ethylene glycol and later thawed for transfer into eCG/pLH-synchronized queens and for HCM, frozen semen from a carrier male was used for laparoscopic oviducal insemination (1 × 106 to 4 × 106 motile sperm/AI) of eCG/pLH-treated females. Ultrasonography was conducted approximately 21 days post-ET or -AI for pregnancy diagnosis. Following IVF with frozen-thawed semen, embryos were produced in all 3 models but overall fertilization success was low (21%, 34/164). All (5/5) recipients became pregnant after ET, giving birth to a total of 11 offspring (6 viable, 5 stillborn). Following frozen ET (PRA), most (3/5) recipients became pregnant with 6 kittens carried to term (3 viable, 3 stillborn), whereas with frozen semen AI (HCM), most (4/7) females conceived with the subsequent birth of 22 kittens (all viable). All surviving offspring (n = 25) for the 5 disease models were distributed to collaborating veterinary schools to reestablish breeding colonies or for ongoing studies. These results indicate that assisted reproduction using frozen semen or embryos may be applied effectively with specific cat models to propagate desired lineages or reestablish research colonies, although some other models have proven more difficult to reproduce. These findings validate our contention that cryopreservation and assisted reproduction may be used to manage and conserve these irreplaceable cat disease models. Funded by NIH grants RR015338, RR02512, HL093603 and HD39888. [ABSTRACT FROM AUTHOR]

The general fine structure of P. splendens Pochman (Section Pleurapsis) is described. This Section comprises a series of species with very distinctive features unshared by the majority of the members of the genus. The cells are pear-shaped in frontal view, rounded at the anterior end, narrowed posteriorly tapering in a long twisted tail. In lateral view, the anterior margins are asymmetric, undulate to serrate. The pellicle is strongly striated, with ribs helically arranged, oriented to the left, concavely depressed between adajcent ribs. In transverse section, the pellicle outline shows a single microtubule in the middle of each rib, on the base of a central sulcus. The other two are located one at each side of the sulcus. Among other distinguishing characteristics, the most remarkable feature is the presence of a single chloroplast, a fact never reported in this genus before since the minimal observed number is two and most of the Phacus species have been described as having numerous, small and discoid chloroplasts. In longitudinal section, a large, leaf-like parietal chloroplast is observed. It extends along the entire cell, bearing three prominent cup-shaped paramylon caps on the external face. In transverse section is C-shaped. The unusual shape and localization of the chloroplast and paramylon in this species resemble descriptions of Cryptoglena pigra, suggesting a closer relationship to this organism than to other members of Phacus. [ABSTRACT FROM AUTHOR]