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Context. The nearby spiral galaxy NGC 3147 hosted three Type Ia supernovae (SNe Ia) in the past decades that have been the subjects of intense follow-up observations. Simultaneous analysis of their data provides a unique opportunity for testing different methods of light curve fitting and distance estimation. Aims. The detailed optical follow-up of SN 2021hpr allows us to revise the previous distance estimations to NGC 3147 and compare the widely used light curve fitting algorithms to each other. After the combination of the available and newly published data of SN 2021hpr, its physical properties can also be estimated with higher accuracy. Methods. We present and analyse new BV griz and Swift photometry of SN 2021hpr to constrain its general physical properties. Together with its siblings, SNe 1997bq and 2008fv, we cross-compared the individual distance estimates of these three SNe given by the Spectral Adaptive Lightcurve Template (SALT) code, and we also checked their consistency with the results from the Multi-Color Light Curve Shape (MLCS) code. The early spectral series of SN 2021hpr was also fit with the radiative spectral code TARDIS to verify the explosion properties and constrain the chemical distribution of the outer ejecta. Results. After combining the distance estimates for the three SNe, the mean distance to their host galaxy, NGC 3127, is 42.5 ± 1.0 Mpc, which matches with the distance inferred by the most up-to-date light curve fitters, SALT3 and BayeSN. We confirm that SN 2021hpr is a Branch-normal Type Ia SN that ejected ~1.12 ± 0.28 M⊙ from its progenitor white dwarf and synthesized ~0.44 ± 0.14 M⊙ of radioactive 56Ni. [ABSTRACT FROM AUTHOR]

The way supermassive black holes (SMBHs) in Galactic Centres (GCs) accumulate their mass is not completely determined. At large scales, it is governed by galactic encounters, mass inflows connected to spirals arms and bars, or due to expanding shells from supernova (SN) explosions in the central parts of galaxies. The investigation of the latter process requires an extensive set of gas dynamical simulations to explore the multidimensional parameter space needed to frame the phenomenon. The aims of this paper are to extend our investigation of the importance of SNe for inducing accretion on to an SMBH and carry out a comparison between the fully hydrodynamic code flash and the much less computationally intensive code ring , which uses the thin shell approximation. We simulate 3D expanding shells in a gravitational potential similar to that of the GC with a variety of homogeneous and turbulent environments. In homogeneous media, we find convincing agreement between flash and ring in the shapes of shells and their equivalent radii throughout their whole evolution until they become subsonic. In highly inhomogeneous, turbulent media, there is also a good agreement of shapes and sizes of shells, and of the times of their first contact with the central 1-pc sphere, where we assume that they join the accretion flow. The comparison supports the proposition that an SN occurring at a galactocentric distance of 5 pc typically drives 1–3 M⊙ into the central 1 pc around the GC. [ABSTRACT FROM AUTHOR]

One of the most important diseases of pea is caused by Pea seed-borne mosaic virus (PSbMV), which has a relatively wide host range. Since there are few varieties with resistance against the virus, and spraying insecticides is not very effective, the determination of the disease and the pathogen in the seeds is very important. Inoculum prepared from pea seeds showing typical virus symptoms caused very mild symptoms on Chenopodium amaranticolor and C. quinoa, but several chlorotic/necrotic lesions on bean (Phaseolus vulgaris) cv. Scarlet, and systemic symptoms with mosaic and curling of top leaves on bean cv. Maxidor. The detection of the virus was carried out by PCR using universal primers and virus sequence analysis. According to the phylogenetic analysis the PSbMV isolate identified in Hungary belongs to the pathotype P1 and associated with the cluster 2 isolates. [ABSTRACT FROM AUTHOR]

The aim of study was to gain a deeper knowledge about local and systemic changes in photosynthetic processes and sugar production of pepper infected by Obuda pepper virus (ObPV) and Pepper mild mottle virus (PMMoV). PSII efficiency, reflectance, and gas exchange were measured 48 and/or 72 h after inoculation (hpi). Sugar accumulation was checked 72 hpi and 20 d after inoculation (as a systemic response). Inoculation of leaves with ObPV led to appearance of hypersensitive necrotic lesions (incompatible interaction), while PMMoV caused no visible symptoms (compatible interaction). ObPV (but not PMMoV) lowered Fv/Fm (from 0.827 to 0.148 at 72 hpi). Net photosynthesis decreased in ObPV-infected leaves. In ObPV-inoculated leaves, the accumulation of glucose, fructose, and glucose-6-phosphate was accompanied with lowered sucrose, maltoheptose, nystose, and trehalose contents. PMMoV inoculation increased the contents of glucose, maltose, and raffinose in the inoculated leaves, while glucose-6-phosphate accummulated in upper leaves. [ABSTRACT FROM AUTHOR]

The thermal neutron cross-sections (σ) of the reactions 164Dy(n,γ) 165Dy, 165Ho(n,γ) 166Ho, 170Er(n, γ) 171Er, 123Sb(n, γ) 124Sb were measured by the activation method. The powder samples were irradiated in an isotropic neutron field obtained from the 241Am-Be and 239Pu-Be neutron sources, moderated with paraffin wax. The γ-ray spectra from the irradiated samples were measured by high resolution γ-ray spectrometry with a calibrated n-type Ge detector. The thermal neutron cross-sections for the reactions studied has been determined to be: for 164Dy(n,γ) 165Dy reaction 2400±200 barns, for 165Ho(n,γ) 166Ho reaction 55.3±12 barns, for 170Er(n, γ) 171Er reaction 1.3±2 barns and for 123Sb(n, γ) 124Sb reaction 3.5±0.5 barns. The thermal neutron cross sections for the reactions 164Dy(n,γ) 165Dy, 165Ho(n,γ) 166Ho and 123Sb(n, γ) 124Sb are in good agreement, within limits of uncertainty, with most of the values in the literature. The thermal neutron cross section for the reaction 170Er(n, γ) 171Er was not in good agreement with the values in the literature, but it is a measurement that has been made, and it can be evaluated again in the future. [ABSTRACT FROM AUTHOR]

Aim Recent evidence suggests that adenosine triphosfate ( ATP)-mediated purinergic signalling at the level of the rostral ventrolateral medulla contributes to both central and peripheral chemoreceptor control of breathing and blood pressure: neurones in the retrotrapezoid nucleus ( RTN) function as central chemoreceptors in part by responding to CO2-evoked ATP release by activation of yet unknown P2 receptors, and nearby catecholaminergic C1 neurones regulate blood pressure responses to peripheral chemoreceptor activation by a P2Y1 receptor-dependent mechanism. However, potential contributions of purinergic signalling in the RTN to cardiorespiratory function in conscious animals have not been tested. Methods Cardiorespiratory activity of unrestrained awake rats was measured in response to RTN injections of ATP, and during exposure to hypercapnia (7% CO2) or hypoxia (8% O2) under control conditions and after bilateral RTN injections of P2 receptor blockers ( PPADS or MRS2179). Results Unilateral injection of ATP into the RTN increased cardiorespiratory output by a P2-recepor-dependent mechanism. We also show that bilateral RTN injections of a non-specific P2 receptor blocker (pyridoxal-phosphate-6-azophenyl-2′,4′-disulfonate ( PPADS) reduced the ventilatory response to hypercapnia (7% CO2) and hypoxia (8% O2) in unanesthetized rats. Conversely, bilateral injections of a specific P2Y1 receptor blocker ( MRS2179) into the RTN had no measurable effect on ventilatory responses elicited by hypercapnia or hypoxia. Conclusion These data exclude P2Y1 receptor involvement in the chemosensory control of breathing at the level of the RTN and show that ATP-mediated purinergic signalling contributes to central and peripheral chemoreflex control of breathing and blood pressure in awake rats. [ABSTRACT FROM AUTHOR]

We present direct spectroscopic modelling of 11 high signal-to-noise ratio observed spectra of the Type Ia supernova (SN) 2010kg, taken between-10 and+5 d with respect to B-maximum. The synthetic spectra, calculated with the SYN++ code, span the range between 4100 and 8500 Å. Our results are in good agreement with previous findings for other Type Ia SNe. Most of the spectral features are formed at or close to the photosphere, but some ions, like Fe II and MgII, also form features at ~2000-5000 km s-1 above the photosphere. The well-known high-velocity features of the Ca II IR-triplet as well as Si II λ6355 are also detected. The single absorption feature at ~4400 Å, which usually has been identified as due to Si III, is poorly fit with Si III in SN 2010kg. We find that the fit can be improved by assuming that this feature is due to either C III or OII, located in the outermost part of the ejecta, ~4000-5000 km s-1 above the photosphere. Since the presence of CIII is unlikely, because of the lack of the necessary excitation/ionization conditions in the outer ejecta, we identify this feature as due to O II. The simultaneous presence of O I and O II is in good agreement with the optical depth calculations and the temperature distribution in the ejecta of SN 2010kg. This could be the first identification of singly ionized oxygen in a Type Ia SN atmosphere. [ABSTRACT FROM AUTHOR]

Brassinosteroids are known to protect plants against various abiotic and biotic stresses, however, very limited information is available about the role of progesterone. Therefore the effects of Pseudomonas syringae pv. syringae ( P.s.) wild type strain 61, its hrcC mutant, and the saprophytic P. fluorescens ( P.f.) strain 55 were investigated in wild type Arabidopsis thaliana cv. Columbia and its rbohF knock-out mutant, with and without progesterone pre-treatment. The reactions of wild type and rbohF mutant Arabidopsis to bacterial inoculations were similar, although 2 h after injection of P.s. a larger increase of electrolyte leakage was measured in wild type than in rbohF knockout mutant leaves. The hrcC mutant caused weak necrotic symptoms and increased leakage in both types of Arabidopsis, although to a much lesser extent than P.s. The P.f. did not induce any visible symptom, but slightly increased the electrolyte leakage in both types of Arabidopsis. Inoculation by all Pseudomonas bacteria led to significant alterations in photosystem 2 efficiency as compared to control plants. Pre-treatment of leaves with progesterone diminished the necrotic symptoms, the electrolyte leakage and improve the efficiency of photosystem 2 caused by Pseudomonas bacteria. [ABSTRACT FROM AUTHOR]

The effect of light on ethylene and ethane production in damaged leaf tissues was investigated. When whole leaves of tobacco cv. Samsun NN were damaged with liquid nitrogen, the ethylene formation was the highest, if 100 % of leaves were injured and were kept in the light, the lowest when leaves after 100 % injury were kept in darkness. Ethane production (lipid peroxidation) could be detected only in damaged, but not in control leaves, and was much higher in light than in darkness. In addition, there was a strong degradation of chlorophyll of damaged leaves kept in light. In light aminoethoxy-vinylglycine (AVG) inhibited ethylene formation in control, non-damaged whole leaves effectively, but in leaves with 100 % damage the inhibitory effect was much weaker and similar to the effect of propyl gallate (PG), a free radical scavenger. Both AVG and PG treatments decreased ethylene formation by control leaf discs and discs with 100 % damage. Ethane production was significantly inhibited by PG and slightly by AVG in the case of 100 % damage. Tiron, another free radical scavenger gave similar results on leaf discs as PG did. Paraquat (methylviologen, Pq), as a photosynthesis inhibiting and reactive oxygen species (ROS) producing herbicide produced a large amount of ethylene and ethane in light but very small amount in darkness. In accordance, tobacco mosaic virus (TMV) infection on the necrotic host resulted in significantly larger amount of ethylene and ethane formation in light than in darkness. We conclude that ethylene and ethane production of damaged plant tissues is strongly induced by light and ROS that are involved in this induction. [ABSTRACT FROM AUTHOR]

The clinical and implicitly medico-legal casuistry show that a number of deceases, having occurred during the hospitalization, enter the suspicious-death category; in this cause the medico-legal autopsy being required, at the prosecuting bodies' written solicitation. In order to prevent the dysfunctions, which might lead to the disappearance of important events in determining the juridical truth in the cause, a close collaboration between the clinical and medico-legal institutions is necessary, based on the legislation afferent to this set of issues. [ABSTRACT FROM AUTHOR]

Different forms and mechanisms of plant resistance are compared in this review, differentiating between innate and acquired resistance. Within innate resistance, general non-specific and specific host resistance are treated as regards the phenomena and mechanisms. Various forms of non-specific (e.g. non-host, basal, quantitative etc.) as well as specific resistance (extreme resistance, gene-for-gene resistance with the hypersensitive response, toxin resistance and gene silencing) are discussed. Within acquired resistance, the immune memory vs. stress memory of animal or plant hosts are compared. Furthermore, mechanisms of acquired resistance of plants are treated in relation to salicylate metabolism, systemic signalling, antioxidants and a recently discovered recombination signal inducing somatic mutations. It seems important for future research trends in plant pathology that several new resistance mechanisms have been discovered or at least re-evaluated, in addition to the specific HR-associated resistance, which has been the subject of the majority of previous research. [ABSTRACT FROM AUTHOR]

Inhibition of senescence of plants increases their resistance to necrotrophic pathogens and to many abiotic stresses. Tomato plants regenerated from tumors induced by Agrobacterium tumefaciens T37 strain showed higher degree of tolerance to Phytophthora infestans infection. As regards the mechanism of the enhanced resistance to necrosis, increased phospholipid and galactolipid contents, in addition to decreased free sterols in the transformed plants gave greater stability to their membranes as compared to membranes from control plants. In addition, the elevated activity of some antioxidant enzymes such as superoxide dismutase and catalase in transformed tissues can also play a significant role in the tolerance to pathogenic and abiotic stresses [ABSTRACT FROM AUTHOR]

Examines the effect of allopurinol in a host-pathogen combination of Triticum aestivum-Puccinia recondita. Wheat-rust interaction; Inhibition of leaf rust development by allopurinol; Electrolyte leakage and liquid peroxidation.

Changes in the activities of superoxide dismutase (SOD; EC 1.15.1.1), peroxidase (POD; EC 1.11.1.7) and catalase (CAT; EC 1.11.1.6) which regulate the persistence of active oxygen species (AOS) were examined in leaves of bean ( Phaseolus vulgaris L. cv. Tendergreen) undergoing compatible and incompatible interactions to race 6 and race 3 strains, respectively, of the halo-blight bacterium Pseudomonas syringae pv. phaseolicola. Resistance of cv. Tendergreen to race 3 is determined by the R3 gene and was expressed by a hypersensitive reaction (HR) which was associated with a rapid increase in lipid peroxidation between 8 and 12 h after inoculation. Five main isoforms of SOD were resolved by native polyacrylamidegel electrophoresis (PAGE). Major changes were found in the activities of the cytosolic Cu, Zn-SOD3 and Cu, ZnSOD5 isoforms, which increased by 6 h after inoculation with race 3, and the possibly peroxisomal MnSOD2 isoform, which decreased rapidly in tissue undergoing the HR. Three further minor isoforms of SOD showed a strong increase in activity during the HR. A low level of extracellular SOD activity was also resolved; two isoforms, one of which increased dramatically in activity during the HR, were detected within intercellular fluids recovered from inoculation sites. Fewer changes in SOD activities were found during the compatible interaction to race 6, and they did not occur until 16 h after inoculation. In tissue around infiltration sites, no decrease in the activity of Mn-SOD2 was observed but slight increases in some other isoforms were found. Four groups of POD isoforms were detected in both 3,3-diaminobenzidine/HO-and o-dianisidine/HO-stained PAGE gels. Significant changes in activity were again associated with development of the HR. In particular, by 2 h after inoculation, increases in POD3a, b and c isoforms were detected within total soluble extracts and also in POD3c within intercellular fluids (no other isoform was found in the apoplasm). By contrast, POD1 and POD2 activities generally declined following inoculation. The principal change in activity in tissues surrounding infiltration sites was an increase in POD3 isoforms following inoculation with race 3. Measurements of total activity showed a decrease in CAT activity as early as 2 h after inoculation, followed by a recovery after 8 h and a further decrease as infiltrated tissue collapsed during the HR. A more-gradual decline in CAT activity was observed at sites undergoing the compatible interaction and also in tissue surrounding inoculation sites. The spatial and temporal changes detected in activities of CAT and isoforms of SOD and POD clearly demonstrate the complexity and potential subtlety of control of the production and persistence of AOS in bean following microbial challenge. The generation of AOS through HR-specific, early increases in extra-cellular POD and SOD isoforms is discussed. [ABSTRACT FROM AUTHOR]

Objectives: To describe relative hazards in sectors of the beryllium industry, risk factors of beryllium disease and sensitisation related to work process were sought in a beryllium manufacturing plant producing pure metal, oxide, alloys, and ceramics.Methods: All 646 active employees were interviewed; beryllium sensitisation was ascertained with the beryllium lymphocyte proliferation blood test on 627 employees; clinical evaluation and bronchoscopy were offered to people with abnormal test results; and industrial hygiene measurements related to work processes taken in 1984-93 were reviewed.Results: 59 employees (9.4%) had abnormal blood tests, 47 of whom underwent bronchoscopy. 24 new cases of beryllium disease were identified, resulting in a beryllium disease prevalence of 4.6%, including five known cases (29/632). Employees who had worked in ceramics had the highest prevalence of beryllium disease (9.0%). Employees in the pebble plant (producing beryllium metal) who had been employed after 1983 also had increased risk, with a prevalence of beryllium disease of 6.4%, compared with 1.3% of other workers hired in the same period, and a prevalence of abnormal blood tests of 19.2%. Logistic regression modelling confirmed these two risk factors for beryllium disease related to work processes and the dependence on time of the risk at the pebble plant. The pebble plant was not associated with the highest gravimetric industrial hygiene measurements available since 1984.Conclusion: Further characterisation of exposures in beryllium metal production may be important to understanding how beryllium exposures confer high contemporary risk of beryllium disease. [ABSTRACT FROM AUTHOR]

Immune inner ear disease results in rapidly progressive, bilateral sensorineural hearing loss and is one of the few forms of sensorineural hearing loss that can be treated medically. The purpose of this study is to identify and preserve several populations of sensitized lymphocytes from patients with immune inner ear disease as a first step toward cloning autoreactive T cells, in order to study the pathogenesis of disease. Lymphocytes from four patients with high reactivity (stimulation index of 2.5 or greater) were placed in frozen storage. At 8 to 14 months they were thawed and restimulated. All four samples were viable. Two reacted again to inner ear homogenate, but with different intensities. Some lymphocytes sensitized to inner ear antigens can retain reactivity after frozen storage. This methodology may be useful to clone highly reactive T cells. [ABSTRACT FROM AUTHOR]

The purpose of this prospective, controlled study was to estimate the prevalence of immune-mediated (autoimmune) inner ear disease in a high-risk patient population, in order to determine the predictive value of a positive lymphocyte transformation test. The high-risk group was defined as any dizzy patient with unilateral or bilateral-asymmetric sensorineural hearing loss, who had not previously received immunotherapy. From more than 400 consecutive patients with a chief complaint of dizziness, 58 were entered into the study over an 8-month period. The control group consisted of 15 normal volunteers. Thirteen patients (22%) one control (7%) had positive lymphocyte transformation tests. The data suggest that positive results in "high-risk" patients are more common than previously believed. Assuming test sensitivity is 96%, specificity 93%, and disease prevalence 22% in high-risk patients, the predictive value of a positive lymphocyte transformation test using inner ear membranes is 79%. That is, approximately three fourths of all positive results are true positives. Positive results in suspected patients, therefore, should be considered true positives, and treatment recommended. Future research should attempt to refine the putative antigen(s), further define "high risk" patients, and prospectively verify these preliminary results. [ABSTRACT FROM AUTHOR]

Since 1981, 28 patients have been diagnosed with autoimmune inner ear disease. This preliminary, retrospective study reviews clinical and laboratory manifestations of autoimmune vestibular dysfunction. Sixteen of 28 patients presented with dizziness (7 vertigo, 8 lightheadedness, 1 ataxia). Twelve of these patients presented with Meniere's syndrome. Seven of 16 dizzy patients underwent formal vestibular testing. Five had reduced vestibular response in the involved ear(s); one patient had positional nystagmus only; and one had normal results. Of 17 patients with adequate follow-up, 11 presented with dizziness. Hearing improved and dizziness resolved in two patients following treatment. Hearing stabilized and dizziness resolved in two. Hearing stabilized but lightheadedness (without vertigo) persisted in five. Hearing was lost and oscillopsia resulted in two patients. Preliminary conclusions are vestibular dysfunction in autoimmune inner ear disease is nonspecific; bilateral vestibular dysfunction is more common; Meniere's syndrome is relatively common; medical management usually is helpful; surgery at this time does not seem appropriate; vestibular treatment results tend to parallel auditory treatment results. [ABSTRACT FROM AUTHOR]

Autoimmune inner ear disease is an uncommon but distinct clinical entity. Our ignorance of the immune mediating pathways, need of further animal model experimentation, variability of laboratory test results and of patient treatment responses illustrate how poorly we understand this disorder. The purpose of this review is to compare practical vs theoretical management of autoimmune inner ear disease, based upon our current knowledge of the disease process and upon a review of clinical experience at the Cleveland Clinic Foundation. Representative case histories are presented. The following preliminary conclusions are discussed: Autoimmune inner ear disease can present as a systemic or localized otologic immune disorder. Hearing loss can begin at any age, with unilateral or bilateral sudden onset, fluctuating or progressive symptoms, with or without associated dizziness. The pathogenesis of autoimmune inner ear disease is probably multifactorial (cellular and humoral). The sensitivity and specificity of different laboratory tests vary greatly, but even the most sensitive tests may be falsely normal when symptoms are not acute or when the patient is taking immunosuppressant medication. The mainstay of autoimmune inner ear treatment is steroids: however, cytotoxic drugs are recommended when there is no response to steroid treatment. Apheresis is reserved for selected cases. Hearing improvement can be dramatic even after 2 months of profound deafness. Flare-ups of autoimmune ear disease are best managed by increasing steroid dosage or adding cytotoxic medications. Unfortunately, some patients will develop progressive hearing loss despite vigorous treatment. [ABSTRACT FROM AUTHOR]

Autoimmune inner ear disease was first described by McCabe in 1979. The diagnosis is supported by cell mediated immune responses to inner ear membrane antigen stimulation. Meniere's disease consists of episodic vertigo, fluctuating sensorineural hearing loss, tinnitus and often aural pressure. Although most clinicians feel that Meniere's disease has no known cause, recently several researchers have suggested that some cases of Meniere's disease may be autoimmune in origin. In the present study, 10 patients with bilateral Meniere's disease were studied prospectively for autoimmune inner ear disease using both cellular and humoral immune tests. Results were compared with normal control subjects. One additional patient with Meniere's disease was identified retrospectively to have positive autoimmune test results. Preliminary conclusions suggest that at least some cases of presumed idiopathic Meniere's disease are autoimmune in origin. Therapeutic implications are significant: the addition of steroids, cytotoxic drugs and/or apheresis to conventional treatment may help prevent total deafness which otherwise might be inevitable. [ABSTRACT FROM AUTHOR]

Computer Automated Measurement and Control (CAMAC) is an instrumentation and interface standard that provides both hardware and software flexibility. Using standard CAMAC modules and a few custom designed routing and clock circuits we have developed a computer-controlled system for general purpose ultrasonic scanning and data acquisition. The CAMAC system provides a relatively easy way of interfacing to the motor controllers and a transient recorder for complete computer control. The main advantage is that the interface software can be written in a high-level language such as FORTRAN to send commands to individual modules in the system to move motors or to activate a transient or to readout the transient recorder data. The system has the capability of performing sequences of commands repeatedly so processes like signal averaging can be easily implemented. New, custom applications can easily be accommodated by changing modules and writing new interface routines in FORTRAN. For example, we have modified the basic system by replacing the transient recorder with a time-to-digital converter and we now have the capability to record time-of-flight ultrasonic data. Another example is the ease with which new scanning devices can be added to the system. The stepper-motor controllers can be reprogrammed to accommodate the characteristics of the new device, again using a high-level language such as FORTRAN. [ABSTRACT FROM AUTHOR]