283 research outputs found
Sink or swim? Modernization of mussel farming methods may negatively impact established seabird communities
Marine aquaculture is the fastest growing sector of global food production and is projected to increase to meet future demand. Expansion and modernization of cultivation methods are needed to reach this target but a cost-benefit evaluation for biodiversity conservation is required to achieve sustainable aquaculture practices. We assess drivers of avian richness and abundance in a long-established seabird community present in a series of longline mussel farms in Italy and in response to a recent modernization process in the farming methodology. Over 2 years (24 surveys) we detected a remarkable diversity (15 species in 5 families) and abundance (n = 5858) of birds, of which 40% (n = 6) are regarded as species of international conservation importance. Our models highlighted that the strongest driver explaining variation in abundance and richness across sites was the type of buoy and the associated cultivation method applied. The older and fast-declining double headrope design, offered greater stability for birds to rest. Conversely, the newer and mechanizable single headrope design dominant method in our study site and projected to replace the older system, was unsuitable for birds. Our findings confirm the function of mussel farms as a sort of marine protected area where low anthropogenic disturbance, higher prey availability and suitable artificial structures promote the establishment of seabird communities with minimal impacts on harvest. However, we suggest that potential modernization of farming methods, important to meet future human demand, needs to be carefully assessed and compensated for, particularly where long-established seabird communities have formed in response to such practices
College Readiness in Mathematics of Senior High School Graduating Students in the Schools District of Paoay
This study primarily determined the college readiness of the Senior High School graduating students as measured by their performance in mathematics. Specifically, it assessed the level of performance in mathematics and level of performance in producing all forms of text, and determined the readiness index of Senior High School graduating students. This descriptive study used 167 randomly selected Senior High School graduating students from four schools in Paoay. The students answered a 50-item validated College Advanced Placement Examination in Algebra and Trigonometry (CAPEAT) and composed 10-15 sentences that describe how they understand mathematics, where it was being used, and the roles of mathematics in their world. Results showed that the majority of the students got low score in the CAPEAT. Most of the students got higher score in Algebra than in Trigonometry. The general mean score of the students is 30.90%. The students are generally low in the mathematics reflection composition (MRC) as evidenced by the modal score of 1 which means that the students are able to elicit the ideas and concepts of the guide questions but show erroneous understanding of these. In general, School B has surpassed the district mean in both CAPEAT and MRC. School D surpassed only the district mean in MRC but not in CAPEAT. Both Schools A and C were not able to exceed the district mean in both CAPEAT and MRC. The college readiness in mathematics of the Senior High School graduating students in the school district of Paoay got low scores and the students need to exert more effort in mathematics. They need to focus and understand the concepts in Algebra and Trigonometry to improve their performance. Moreover, the students must review the concepts learned to be ready in tertiary mathematics
Haplosporidium pinnae Detection from the Faeces of Pinna nobilis: A Quick and Noninvasive Tool to Monitor the Presence of Pathogen in Early-Stage or during Fan Mussel Mass Mortalities
Due to the increasing mass mortality of Pinna nobilis, mainly caused by the protozoan Haplosporidium pinnae along the Mediterranean Sea, it is necessary to develop rapid and effective methods to detect the pathogen. The present study describes the development and validation of a species-specific assay based on hydrolysis probe chemistry to detect H. pinnae DNA from faeces and pseudofaeces of P. nobilis. During a study campaign in the Gulf of Trieste (Italy) in the spring and summer of 2022, 18 samples (10 faeces and 8 pseudofaeces) were collected. DNA was isolated from all samples and the presence of H. pinnae was tested by amplifying a small portion of 18S rDNA using qPCR. The newly developed assay detected positive H. pinnae in the faeces of the fan mussel in the spring, while no evidence of an outbreak of H. pinnae was found in the summer. In addition, the method proved to be noninvasive and can be used to monitor suspected H. pinnae infections in the early stages when bivalves are still vital. Furthermore, fecal analysis allows the monitoring of P. nobilis without dissecting tissues. The presented assay can also be used to routinely monitor the progress of mass mortalities caused by H. pinnae and to screen for the pathogen in live fan mussels and other environmental matrices, such as water, sediment, and faeces from other species that can host the protozoan
A Convenient Model of Severe, High Incidence Autoimmune Gastritis Caused by Polyclonal Effector T Cells and without Perturbation of Regulatory T Cells
Autoimmune gastritis results from the breakdown of T cell tolerance to the gastric H+/K+ ATPase. The gastric H+/K+ ATPase is responsible for the acidification of gastric juice and consists of an α subunit (H/Kα) and a β subunit (H/Kβ). Here we show that CD4+ T cells from H/Kα-deficient mice (H/Kα−/−) are highly pathogenic and autoimmune gastritis can be induced in sublethally irradiated wildtype mice by adoptive transfer of unfractionated CD4+ T cells from H/Kα−/− mice. All recipient mice consistently developed the most severe form of autoimmune gastritis 8 weeks after the transfer, featuring hypertrophy of the gastric mucosa, complete depletion of the parietal and zymogenic cells, and presence of autoantibodies to H+/K+ ATPase in the serum. Furthermore, we demonstrated that the disease significantly affected stomach weight and stomach pH of recipient mice. Depletion of parietal cells in this disease model required the presence of both H/Kα and H/Kβ since transfer of H/Kα−/− CD4+ T cells did not result in depletion of parietal cells in H/Kα−/− or H/Kβ−/− recipient mice. The consistency of disease severity, the use of polyclonal T cells and a specific T cell response to the gastric autoantigen make this an ideal disease model for the study of many aspects of organ-specific autoimmunity including prevention and treatment of the disease
Trimethoxylated halogenated chalcones as dual inhibitors of mao-b and bace-1 for the treatment of neurodegenerative disorders
Six halogenated trimethoxy chalcone derivatives (CH1–CH6) were synthesized and spec-trally characterized. The compounds were further evaluated for their inhibitory potential against monoamine oxidases (MAOs) and β-secretase (BACE-1). Six compounds inhibited MAO-B more effectively than MAO-A, and the 2′,3′,4′-methoxy moiety in CH4–CH6 was more effective for MAO-B inhibition than the 2′,4′,6′-methoxy moiety in CH1–CH3. Compound CH5 most potently inhibited MAO-B, with an IC50 value of 0.46 µM, followed by CH4 (IC50 = 0.84 µM). In 2′,3′,4′-methoxy derivatives (CH4-CH6), the order of inhibition was –Br in CH5 >-Cl in CH4 >-F in CH6 at the para-position in ring B of chalcone. CH4 and CH5 were selective for MAO-B, with selectivity index (SI) values of 15.1 and 31.3, respectively, over MAO-A. CH4 and CH5 moderately inhibited BACE-1 with IC50 values of 13.6 and 19.8 µM, respectively. When CH4 and CH5 were assessed for their cell viability studies on the normal African Green Monkey kidney cell line (VERO) using MTT assays, it was noted that both compounds were found to be safe, and only a slightly toxic effect was observed in concentrations above 200 µg/mL. CH4 and CH5 decreased reactive oxygen species (ROS) levels of VERO cells treated with H2 O2, indicating both compounds retained protective effects on the cells by antioxidant activities. All compounds showed high blood brain barrier permeabilities analyzed by a parallel artificial membrane permeability assay (PAMPA). Molecular docking and ADME prediction of the lead compounds provided more insights into the rationale behind the binding and the CNS drug likeness. From non-test mutagenicity and cardiotoxicity studies, CH4 and CH5 were non-mutagenic and non-/weak-cardiotoxic. These results suggest that CH4 and CH5 could be considered candidates for the cure of neurological dysfunctions
Serum methylarginines and spirometry-measured lung function in older adults
Rationale: Methylarginines are endogenous nitric oxide synthase inhibitors that have been implicated in animal models of lung disease but have not previously been examined for their association with spirometric measures of lung function in humans.
Objectives: This study measured serum concentrations of asymmetric and symmetric dimethylarginine in a representative sample of older community-dwelling adults and determined their association with spirometric lung function measures.
Methods: Data on clinical, lifestyle, and demographic characteristics, methylated arginines, and L-arginine (measured using LC-MS/MS) were collected from a population-based sample of older Australian adults from the Hunter Community Study.
The five key lung function measures included as outcomes were Forced Expiratory Volume in 1 second, Forced Vital Capacity, Forced Expiratory Volume in 1 second to Forced Vital Capacity ratio, Percent Predicted Forced Expiratory Volume in 1 second, and Percent Predicted Forced Vital Capacity.
Measurements and Main Results: In adjusted analyses there were statistically significant independent associations between a) higher asymmetric dimethylarginine, lower Forced Expiratory Volume in 1 second and lower Forced Vital Capacity; and b) lower L-arginine/asymmetric dimethylarginine ratio, lower Forced Expiratory Volume in 1 second, lower Percent Predicted Forced Expiratory Volume in 1 second and lower Percent Predicted Forced Vital Capacity. By contrast, no significant associations were observed between symmetric dimethylarginine and lung function.
Conclusions: After adjusting for clinical, demographic, biochemical, and pharmacological confounders, higher serum asymmetric dimethylarginine was independently associated with a reduction in key measures of lung function. Further research is needed to determine if methylarginines predict the decline in lung function
TeraHertz Exploration and Zooming-in for Astrophysics (THEZA): ESA Voyage 2050 White Paper
This paper presents the ESA Voyage 2050 White Paper for a concept of
TeraHertz Exploration and Zooming-in for Astrophysics (THEZA). It addresses the
science case and some implementation issues of a space-borne radio
interferometric system for ultra-sharp imaging of celestial radio sources at
the level of angular resolution down to (sub-) microarcseconds. THEZA focuses
at millimetre and sub-millimetre wavelengths (frequencies above 300~GHz),
but allows for science operations at longer wavelengths too. The THEZA concept
science rationale is focused on the physics of spacetime in the vicinity of
supermassive black holes as the leading science driver. The main aim of the
concept is to facilitate a major leap by providing researchers with orders of
magnitude improvements in the resolution and dynamic range in direct imaging
studies of the most exotic objects in the Universe, black holes. The concept
will open up a sizeable range of hitherto unreachable parameters of
observational astrophysics. It unifies two major lines of development of
space-borne radio astronomy of the past decades: Space VLBI (Very Long Baseline
Interferometry) and mm- and sub-mm astrophysical studies with "single dish"
instruments. It also builds upon the recent success of the Earth-based Event
Horizon Telescope (EHT) -- the first-ever direct image of a shadow of the
super-massive black hole in the centre of the galaxy M87. As an amalgam of
these three major areas of modern observational astrophysics, THEZA aims at
facilitating a breakthrough in high-resolution high image quality studies in
the millimetre and sub-millimetre domain of the electromagnetic spectrum.Comment: White Paper submitted in response to the ESA Call Voyage 205
Intraepithelial and Interstitial Deposition of Pathological Prion Protein in Kidneys of Scrapie-Affected Sheep
Prions have been documented in extra-neuronal and extra-lymphatic tissues of humans and various ruminants affected by Transmissible Spongiform Encephalopathy (TSE). The presence of prion infectivity detected in cervid and ovine blood tempted us to reason that kidney, the organ filtrating blood derived proteins, may accumulate disease associated PrPSc. We collected and screened kidneys of experimentally, naturally scrapie-affected and control sheep for renal deposition of PrPSc from distinct, geographically separated flocks. By performing Western blot, PET blot analysis and immunohistochemistry we found intraepithelial (cortex, medulla and papilla) and occasional interstitial (papilla) deposition of PrPSc in kidneys of scrapie-affected sheep. Interestingly, glomerula lacked detectable signals indicative of PrPSc. PrPSc was also detected in kidneys of subclinical sheep, but to significantly lower degree. Depending on the stage of the disease the incidence of PrPSc in kidney varied from approximately 27% (subclinical) to 73.6% (clinical) in naturally scrapie-affected sheep. Kidneys from flocks without scrapie outbreak were devoid of PrPSc. Here we demonstrate unexpectedly frequent deposition of high levels of PrPSc in ovine kidneys of various flocks. Renal deposition of PrPSc is likely to be a pre-requisite enabling prionuria, a possible co-factor of horizontal prion-transmission in sheep
First M87 Event Horizon Telescope Results and the Role of ALMA
In April 2019, the Event Horizon Telescope (EHT) collaboration revealed the
first image of the candidate super-massive black hole (SMBH) at the centre of
the giant elliptical galaxy Messier 87 (M87). This event-horizon-scale image
shows a ring of glowing plasma with a dark patch at the centre, which is
interpreted as the shadow of the black hole. This breakthrough result, which
represents a powerful confirmation of Einstein's theory of gravity, or general
relativity, was made possible by assembling a global network of radio
telescopes operating at millimetre wavelengths that for the first time included
the Atacama Large Millimeter/ submillimeter Array (ALMA). The addition of ALMA
as an anchor station has enabled a giant leap forward by increasing the
sensitivity limits of the EHT by an order of magnitude, effectively turning it
into an imaging array. The published image demonstrates that it is now possible
to directly study the event horizon shadows of SMBHs via electromagnetic
radiation, thereby transforming this elusive frontier from a mathematical
concept into an astrophysical reality. The expansion of the array over the next
few years will include new stations on different continents - and eventually
satellites in space. This will provide progressively sharper and
higher-fidelity images of SMBH candidates, and potentially even movies of the
hot plasma orbiting around SMBHs. These improvements will shed light on the
processes of black hole accretion and jet formation on event-horizon scales,
thereby enabling more precise tests of general relativity in the truly strong
field regime.Comment: 11 pages + cover page, 6 figure
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