1,747 research outputs found
Interactions between shorebirds and benthic invertebrates at Culbin Sands lagoon, NE Scotland: effects of avian predation on their prey community density and structure
In the North Sea, during autumn-winter, intertidal flats often receive a massive influx of migratory shorebirds (wildfowl, waders and seabirds), which utilise the high prey densities that are available. The present study was conducted at Culbin Sands lagoon, NE Scotland, in 1994-1996, to investigate benthic invertebrate standing stock, and the energy flow from benthic invertebrates to shorebirds. Benthic invertebrate standing stock was estimated to be 500 kJ m(-2) yr(-1), and shorebird consumption efficiency to be 18% of the available standing stock. A series of manipulative field experiments were then conducted to test the effects of shorebirds on benthic invertebrate densities and community structure. Birds were excluded from caged areas (exclosures), and benthic invertebrate densities (total and by class size) in caged and uncaged areas were compared for each season separately. During autumn-winter, especially the gastropod Hydrobia ulvae and larger-sized (> 15 mm) clams Macoma balthica were observed to be the roost impacted species, being significantly more abundant in bird-exclosures than in bird-accessed areas.info:eu-repo/semantics/publishedVersio
Cover crop introduction in a Mediterranean maize cropping system. Effects on soil variables and yield
Cover crops (CCs) are able to affect subsequent crop behaviour by acting on many soil
variables and affecting the dynamics of different ecological processes. This study aimed to investigate
the effects of introducing CC in continuous-maize cropping systems within Mediterranean areas. The
experimental site was located in Central Italy, on a sandy loam and the research activity was carried
out over two years (2019–2020). The two cropping systems in comparison differed from each other
in terms of the CC cultivation: TR (treated, with CC) and CO (control, without CC). In both years,
we observed a significant reduction (p < 0.05) of soil nitrate and water content for the TR system. In
the shallowest layer (0–30 cm), nitrate content was reduced by up 80% and 65% (July 2019 and
2020), whereas soil moisture showed decreases ranging from 13% (July 2019) to 34% (May 2019).
In 2019, the TR-maize (Zea mays L.) yield was statistically lower than CO (443 g dm m2), whereas
in 2020 the yields of the two systems resulted statistically equivalent. This different behaviour can
be explained with the serious delay in the CC sowing occurred in 2019 (12 December). Conversely,
an increase in the apparent remaining N in the soil (+140 and +133 kg N ha1 for 2019 and 2020,
respectively) and in the C (carbon) inputs (+4.78 and +7.39 t dm ha1 of biomass) were pointed out
for the TR system. The large use of inputs in Mediterranean maize cropping systems limited some of
the benefits from CCs, but their suitability has to be evaluated by considering all the involved effects,
some of which need a long time to become appreciable
Headache and pregnancy. a systematic review
This systematic review summarizes the existing data on headache and pregnancy with a scope on clinical headache phenotypes, treatment of headaches in pregnancy and effects of headache medications on the child during pregnancy and breastfeeding, headache related complications, and diagnostics of headache in pregnancy. Headache during pregnancy can be both primary and secondary, and in the last case can be a symptom of a life-threatening condition. The most common secondary headaches are stroke, cerebral venous thrombosis, subarachnoid hemorrhage, pituitary tumor, choriocarcinoma, eclampsia, preeclampsia, idiopathic intracranial hypertension, and reversible cerebral vasoconstriction syndrome. Migraine is a risk factor for pregnancy complications, particularly vascular events. Data regarding other primary headache conditions are still scarce. Early diagnostics of the disease manifested by headache is important for mother and fetus life. It is especially important to identify "red flag symptoms" suggesting that headache is a symptom of a serious disease. In order to exclude a secondary headache additional studies can be necessary: electroencephalography, ultrasound of the vessels of the head and neck, brain MRI and MR angiography with contrast ophthalmoscopy and lumbar puncture. During pregnancy and breastfeeding the preferred therapeutic strategy for the treatment of primary headaches should always be a non-pharmacological one. Treatment should not be postponed as an undermanaged headache can lead to stress, sleep deprivation, depression and poor nutritional intake that in turn can have negative consequences for both mother and baby. Therefore, if non-pharmacological interventions seem inadequate, a well-considered choice should be made concerning the use of medication, taking into account all the benefits and possible risks
Optical devices provide unprecedented insights into the laser cleaning of calcium oxalate layers
Abstract Calcium oxalates are insoluble colorless or whitish salts constituting noble patina, on both natural and artificial stone artworks' surfaces, the presence of which is extremely valued. The oxalates are not considered detrimental to the substrate, however, being often accompanied by other substances such as gypsum, silicates, and pigmented particles. They may form very adherent, relatively thick and colored layers creating disfiguring effects and hindering legibility of the pictorial surface. For this reason it may be appropriate to diminish their thickness, but patina's partial preservation is particularly required calling for extremely gradual and controllable cleaning approach. Thinning of calcium oxalate patina from a detached 16th century fresco (from Sansepolcro) was performed through the use of laser (Nd:YAG and Er:YAG) systems and chemical means (Carbogel loaded 5 wt.% of tetrasodium EDTA). Optical coherence tomography (OCT), providing a non-invasive stratigraphic cross-section of the examined surface, allowed to distinguish the oxalate from the underlying original layers and therefore to have an overview about its distribution, to numerically evaluate patina's thickness range and to provide the information on the amount of the material both removed and left on the artwork's surface. Laser scanning conoscopic microprofilometry allowed for a high-density sampling of the artwork's surface providing a three-dimensional model of the surface pattern. The obtained 3D models were used to estimate the amount of material removed and to compare them with those provided by OCT. The successful exploitation of the proposed exceptional cleaning monitoring methodology may be seen as an innovative and valid support for the restorers in the conservation of mural painting or other surfaces covered by oxalate layers and may pilot more targeted, cautious and respectful cleaning intervention
An update on treatment options for interstitial cystitis
Interstitial cystitis or bladder pain syndrome (IC/BPS) is a chronic pelvic pain syndrome related to the urinary bladder. The ideal treatment should match as much as possible with the pathophysiologic causes of the IC/BPS, but the scarcely available evidence limits this approach, with the majority of available treatments that are primarily targeted to the control of symptoms. The treatment strategies have traditionally focused on the bladder, which is considered the primary end-organ and source of pain. Nevertheless, the growing body of evidence suggests a multifaceted nature of the disease with systemic components. In general, guidelines recommend the personalized and progressive approach, that starts from the more conservative options and then advances toward more invasive and combined treatments. The behavioral changes represent the first and most conservative steps. They can be combined with oral medications or progressively with intravesical instillation of drugs, up to more invasive techniques in a combined way. Despite the multiple available options, the optimal treatment is not easy to be found. Only further investigation on the etiopathogenetic mechanisms, taking into account the differences among subgroups, and the interaction between central and peripherical factors may allow providing a real improvement in the treatment and management of these patients
How Do Brazilian Street Youth Experience ‘The Street’?: Analysis Of A Sentence Completion Task
This study investigated how homeless Brazilian youth experience the street and examined factors linked to positive and negative feelings about the street. An opportunity sample of 35 boys and 34 girls aged 10–18 completed a structured interview and sentence completion task aimed at eliciting open-ended responses in a standardized manner. Analyses revealed great diversity in youths’ views of the street; moreover, in analyses controlling for age and gender, youth reporting feeling positive on the street differed from those who felt negative in reasons for leaving home, family situation and daily survival. The findings support the value of the sentence completion task in exploring the subjective experiences of street youth
An autonomous ground mobile unit for the precision physical weed control.
In this paper the design, the main characteristics and the automation systems of innovative
autonomous ground mobile units (GMU) for physical weed control (PWC) in maize are
described. The machine will be created within the activities of the European Project RHEA
(Robot fleets for Highly Effective Agriculture and forestry management), that aims to produce
different prototypes of autonomous terrestrial and aerial robot able to perform several
activities related to the general crop protection in different agricultural scenarios. The first
autonomous ground unit machine was designed in order to perform a mechanical and
thermal treatment removing weeds from the inter-row crop space and applying in-row
selective and precision flaming by means of two crossed LPG rod burners. By means of
some modifications of the tools it will be possible to realize also an autonomous unit for the
precision broadcast flaming application. In this case the design involves a replacement of the
mechanical tools working in the inter-row space with 50 cm wide burners able to perform
flaming at different intensities according to weed cover detected by the perception system of
the robot. The working width of both the PWC machines will be of 4.5 m, thus covering five
entire maize inter-row spaces of 0.75 m each and 2 half inter-row space of 0.375 m each.
The correct position of the tools (mechanical and thermal) will be guaranteed by an
automatic precision guidance system connected and supervised to an image based row
detection system. Each working elements will be provided by two crossed 0.25 m wide rod
burners, hitting one side of each crop row. The flame should hit the weeds growing in the “inrow”
space (a 0.25 m wide strip of soil with the maize plant in the middle). Regarding the
control of the weed emerged in the “inter-row” space each working unit of the will be provided
with rigid tools (one central foot-goose and two side “L” shaped sweeps). The mechanical
treatment will be performed, independently from the weed presence, as hoeing is a very
important agronomical practice. On the contrary, broadcast flaming in the inter-row space will
be performed after weed detection, using three different LPG pressures and doses according
to weed cover (no weed cover-no treatment, weed cover between 0 and 25%-flaming at 0.3
MPa, weed cover higher than 25%-flaming at 0.4 MPa). This very innovative application of
precision PWC in maize could represent not only a good opportunity for farmers in term of
herbicide use reduction, but also an environmental friendly and energy saving application of
flaming in organic farming
Dynamical instabilities in a simple minority game with discounting
We explore the effect of discounting and experimentation in a simple model of
interacting adaptive agents. Agents belong to either of two types and each has
to decide whether to participate a game or not, the game being profitable when
there is an excess of players of the other type. We find the emergence of large
fluctuations as a result of the onset of a dynamical instability which may
arise discontinuously (increasing the discount factor) or continuously
(decreasing the experimentation rate). The phase diagram is characterized in
detail and noise amplification close to a bifurcation point is identified as
the physical mechanism behind the instability.Comment: 8 page
Design, status and perspective of the Mu2e crystal calorimeter
The Mu2e experiment at Fermilab will search for the charged lepton flavor
violating process of neutrino-less coherent conversion in the field
of an aluminum nucleus. Mu2e will reach a single event sensitivity of about
that corresponds to four orders of magnitude improvements
with respect to the current best limit. The detector system consists of a straw
tube tracker and a crystal calorimeter made of undoped CsI coupled with Silicon
Photomultipliers. The calorimeter was designed to be operable in a harsh
environment where about 10 krad/year will be delivered in the hottest region
and work in presence of 1 T magnetic field. The calorimeter role is to perform
/e separation to suppress cosmic muons mimiking the signal, while
providing a high level trigger and a seeding the track search in the tracker.
In this paper we present the calorimeter design and the latest RD results.Comment: 4 pages, conference proceeding for a presentation held at TIPP'2017.
To be published on Springer Proceedings in Physic
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