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Neutron activation analysis is the reference method used for offline determination of the neutron flux density in defined positions. It can be used in the nuclear energy industry-as well as in medical- or space applications. For accurate neutron flux evaluation, well-known and reliable cross sections are needed. In the thermal and fast energy region, many reliable monitoring reactions exists, however, in case of the epithermal and intermediate energy region, there are practically no dosimetry nuclear reactions sensitive specifically in this energy range. Due to this fact, both new data are being measured and methodologies are under development to describe and test this energy region. It was found that various neutron filters can be used to cut parts of neutron spectra and thus methodology based on spectrum filtering could potentially be employed to survey cross sections of interest. It this paper, the use of 3 different filters - B4C, Cd, and In is studied, on the case of the 55Mn(n,γ) reaction. Measured values of that cross section in the given filtered reference spectra are reported.One of the commonly performed studies in nuclear medicine are bone scans with [99mTc]Tc-methylene diphosphonate (MDP) for detecting various bone lesions, including cancer metastasis. The recent emergence of commercially available 68Ge/68Ga radionuclide generators makes it possible to provide 68Ga-labelled bisphosphonates as positron emission tomography (PET) tracers for bone imaging. Preliminary human studies suggested that [68Ga]Ga-HBED-CC-BP ([68Ga]Ga-P15-041) in conjunction with PET/computed tomography (CT) showed accumulation in known bone lesions, fast clearance from blood and soft tissue, and an ability to provide high contrast images. A simple and efficient lyophilized P15-041 kit formulation for the rapid production of [68Ga]Ga-P15-041 with excellent radiochemical purity (RCP) under ambient temperature without the need for purification is described. It is demonstrated that clinical doses of [68Ga]Ga-P15-041 can be prepared manually within minutes with an excellent purity (> 90%) and readily meet the dose release criteria. When [68Ga]Ga-P15-041 was evaluated in a patient with cancer, the imaging agent clearly showed accumulations in multiple lesions. In conclusion, [68Ga]Ga-P15-041, prepared by a lyophilized kit, might be an excellent bone imaging agent for widespread clinical application.We report an unusual case of synchronous papillary carcinoma of thyroglossal duct cyst (TGDC) and thyroid gland. Here, the radiology findings, surgical approach and subsequent management, and pathology of an synchronous papillary carcinoma of TGDC and thyroid gland are described.Extraskeletal Ewing sarcoma (EES) is a rare soft tissue tumor, and EES of the head and neck is particularly rare. Radiographic imaging of these lesions is crucial given their anatomical complexity and infrequent incidence. Conventional EES imaging features include a large, hyperintense, heterogeneously enhancing lesion, with frequent invasion of local structures. In this case report, a 19-year old male presented with left facial swelling and pain. He underwent sclerotherapy and bleomycin treatment for a presumed lymphatic malformation. Initial imaging demonstrated a rim-enhancing lesion within the left buccal space with no muscle invasion or bony erosion present. Two years later, imaging identified an enlarging buccal mass with destruction of the zygomatic arch and inferolateral orbital wall. The patient underwent surgical resection of the mass. Pathology confirmed the mass to be a small round blue cell tumor and FISH testing confirmed the presence of the EWSR1 gene arrangement that is consistent with EES. The patient tolerated the procedure well and underwent chemoradiation therapy. At three years postoperatively, the patient remains disease free. The presented case demonstrates an unusual presentation of a buccal space EES as a rim-enhancing, centrally hypointense mass with no bony erosion or muscular invasion. The location and atypical imaging appearance of this case offer insight for future diagnosis of EES.SUMOylation is an important post-translational modification process involving covalent attachment of SUMO (Small Ubiquitin-like MOdifier) protein to target proteins. Here, we investigated the potential for SUMO-1 protein to modulate the function of the CaV2.2 (N-type) voltage-gated calcium channel (VGCC), a protein vital for presynaptic neurotransmitter release. Co-expression of SUMO-1, but not the conjugation-deficient mutant SUMO-1ΔGG, increased heterologously-expressed CaV2.2 Ca2+ current density, an effect potentiated by the conjugating enzyme Ubc9. Expression of sentrin-specific protease (SENP)-1 or Ubc9 alone, had no effect on recombinant CaV2.2 channels. Co-expression of SUMO-1 and Ubc9 caused an increase in whole-cell maximal conductance (Gmax) and a hyperpolarizing shift in the midpoint of activation (V1/2). Mutation of all five CaV2.2 lysine residues to arginine within the five highest probability (>65 %) SUMOylation consensus motifs (SCMs) (construct CaV2.2-Δ5KR), produced a loss-of-function mutant. Mutagenesis of selected individual lysine residues identified K394, but not K951, as a key residue for SUMO-1-mediated increase in CaV2.2 Ca2+ current density. In synaptically-coupled superior cervical ganglion (SCG) neurons, SUMO-1 protein was distributed throughout the cell body, axons and dendrites and presumptive presynaptic terminals, whilst SUMO-1ΔGG protein was largely confined to the cell body, in particular, the nucleus. SUMO-1 expression caused increases in paired excitatory postsynaptic potential (EPSP) ratio at short (20-120 ms) inter-stimuli intervals in comparison to SUMO-1ΔGG, consistent with an increase in residual presynaptic Ca2+ current and an increase in release probability of synaptic vesicles. Epigenetic inhibitors Together, these data provide evidence for CaV2.2 VGCCs as novel targets for SUMOylation pathways.Molecular plant-virus interactions provide an excellent model to understanding host antiviral immunity and viral counter-defense mechanisms. The primary antiviral defense is triggered inside the infected plant cell by virus-derived small-interfering RNAs, which guide homology-dependent RNA interference (RNAi) and/or RNA-directed DNA methylation (RdDM) to target RNA and DNA viruses. In counter-defense, plant viruses have independently evolved viral suppressors of RNAi (VSRs) to specifically antagonize antiviral RNAi. Recent studies have shown that plant antiviral responses are regulated by endogenous small silencing RNAs, RNA decay and autophagy and that some known VSRs of plant RNA and DNA viruses also target these newly recognized defense responses to promote infection. This review focuses on these recent advances that have revealed multilayered regulation of plant-virus interactions.

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