1,035 research outputs found
Could payments for environmental services improve rangeland management in Central Asia, West Asia and North Africa?:
"Although several institutional and management approaches that address the degradation of the rangelands have been tested in the dry areas of Central and West Asia and North Africa (CWANA), impact has been limited. Nonetheless, the development of National Action Plans to combat desertification highlights the interest of governments to tackle this issue. Payment for Environmental Services (PES) may be a viable policy option, though, to date, most PES programs have focused on the management of different resources (forests, watersheds). The purpose of this paper is to examine whether PES could be a viable option to promote sustainable rangelands management in the dry rangelands of CWANA. Specifically, it focuses on the scientific gaps and knowledge related to the local and global environmental services produced by rangelands and addresses questions related to the beneficiaries of these services. Institutional conditions necessary for the implementation of such schemes are discussed." Authors' AbstractEnvironmental services, Environmental management, Land management, Rangelands, Collective action, Property rights,
Pseudo-attractors in Random Boolean Network Models and Single-Cell Data
In this extended abstract two novel concepts are defined in the
study of Random Boolean Networks, i.e. those of âpseudoattractorsâ
and âcommon seaâ, and it is shown how their
analogues can be measured in experimental data on gene
expression in single cells
Molecular Mechanism of the Piezoelectric Response in the ÎČ-Phase PVDF Crystals Interpreted by Periodic Boundary Conditions DFT Calculations
A theoretical approach based on Periodic Boundary Conditions (PBC) and a Linear Combination of Atomic Orbitals (LCAO) in the framework of the density functional theory (DFT) is used to investigate the molecular mechanism that rules the piezoelectric behavior of poly(vinylidene fluoride) (PVDF) polymer in the crystalline beta-phase. We present several computational tests highlighting the peculiar electrostatic potential energy landscape the polymer chains feel when they change their orientation by a rigid rotation in the lattice cell. We demonstrate that a rotation of the permanent dipole through chain rotation has a rather low energy cost and leads to a lattice relaxation. This justifies the macroscopic strain observed when the material is subjected to an electric field. Moreover, we investigate the effect on the molecular geometry of the expansion of the lattice parameters in the (a, b) plane, proving that the rotation of the dipole can take place spontaneously under mechanical deformation. By band deconvolution of the IR and Raman spectra of a PVDF film with a high content of beta-phase, we provide the experimental phonon wavenumbers and relative band intensities, which we compare against the predictions from DFT calculations. This analysis shows the reliability of the LCAO approach, as implemented in the CRYSTAL software, for calculating the vibrational spectra. Finally, we investigate how the IR/Raman spectra evolve as a function of inter-chain distance, moving towards the isolated chain limit and to the limit of a single crystal slab. The results show the relevance of the inter-molecular interactions on the vibrational dynamics and on the electro-optical features ruling the intensity pattern of the vibrational spectra
Response of captive seabass and seabream as behavioural indicator in aquaculture
Welfare of cultivate fish at high-density represents an important concern for modern aquaculture.
The behaviour of European seabass (Dicentrarchus labrax) and seabream (Sparus aurata) reared in cages was studied
in a fish farm of northern Sardinia (Italy) in autumn 2006 to test whether captive condition had an effect on
the movement patterns of these two species.Video images recorded before, during and after the manual feeding distribution
allowed us to collect data on different behaviours of captive fish. Thus, behaviours indicating the position
of fish in the water column, swimming direction and possible aggressive behaviours (aggression, direction change
and collision) showed juveniles and adults of seabass and seabream were overall affected by feeding rhythms and
captive overcrowding. Seabream had a major tendency to swim towards the bottom and higher frequency of horizontal
swimming and collisions than seabass. The overall behavioural difference between two species was explained
in terms of their differences in ecological features in the wild
A new system of authorship best assessment
Purpose:The standard bibliometric indexes ("m-quotient "H-," "H2-," "g-," "a-," "m-," and "r-" index) do not considered the research' position in the author list of the paper. We proposed a new methodology, System of Authorship Best Assessment (SABA), to characterize the scientific output based on authors' position. Material and Methods:Four classes S1A, S1B, S2A, and S2B include only papers where the researcher is in first, first/last, first/second/last, and first/second/second-last/last position respectively were used for the calculation of H-index and number of citations The system was tested with Noble prize winners controlled with researchers matched for H-index. The different in percentage between standard bibliometric index and S2B was calculated and compared. Results:The percentage differences in Noble prize winners between S2B-H-index versus Global H-index and number of citations is very lower comparing with control group (median 4.15% [adjusted 95% CI, 2.54-5.30] vs 9.00 [adjusted 95% CI, 7.16-11.84], p < 0.001; average difference 8.7% vs 20.3%). All different in percentage between standard bibliometric index and S2B except two (H2- and m-index) were significantly lower among Noble prize compared with control group. Conclusion:The SABA methodology better weight the research impact by showing that for excellent profiles the S2B is similar to global values whereas for other researchers there is a significant difference
Precision medicine and precision nursing. The era of biomarkers and precision health
Precision health, by means of the support of precision medicine and precision nursing, is able to support clinical decision making in order to tailor optimal health-care decisions, around the individual characteristics of patients. The operational arm of precision health is represented by the use of biomarkers that can give useful information about disease susceptibility, exposure, evolution and response to treatment. Omics, imaging and clinical biomarkers are actually studied for their ability to positively impact health-care management. In this article, we try to address the role of biomarkers in the context of modern medicine and nursing with the view of improving patients care
Pancreatic nodule positive for 68-Ga-DOTAPEPTIDE-PET: NET or ectopic spleen? The importance of a good differential diagnosis
Abstract
Background
Accessory spleen is a congenital defect in which splenic tissue is present outside the spleen. In 20% of cases, accessory spleen is localized within the pancreatic tail, a condition known as IPAS. The identification of this benign anomaly, which affects about 2% of general population, is not easy because it is often mistaken for a pNET which is more common, at around 5%. A 68-Ga-DOTAPEPTIDE-PET normally identifies pNETs with high rate of sensitivity and specificity, but in some conditions, it produces false positives, including IPAS.
Materials and tools
A clinical case we recently encountered, prompted us to review the available medical literature on the topic. Typing "intrapancreatic accessory spleen" into PubMed database and limiting research to the last 10 years yielded 121 results from which we selected the most relevant articles for decision-making, with a brief explanation of the reasons for selecting those. Our analysis focused on the most critical and least descriptive articles, those which clearly indicated the importance of differential diagnosis by promoting the use of advanced investigations in case of pancreatic nodule suspected for IPAS. Ultimately, our objective was to update the available guidelines recommendations.
Discussion and conclusions
Despite concern in the medical literature, a differential IPAS diagnosis is still subordinate to other clinical, radiological, nuclear medicine, and cytological criteria. After reviewing the literature, we recommend that IPAS should always be considered as a possibility before diagnosis of pNET is made. IPAS should be suspected in the presence of the following findings: asymptomatic pancreatic nodule found incidentally, absence of laboratory findings of NETs, localization in the pancreatic tail, between 1 and 3 cm in size with well-defined margins, homogeneous enhancement, and similar attenuation to the spleen on CT and MRI. In these cases, the use of advanced investigations beyond 68-Ga-DOTAPEPTIDE-PET must be systematic. The recognition of IPAS is not only a diagnostic refinement, but it also avoids unnecessary surgery for the patient
The hidden life of NAD+-consuming ectoenzymes in the endocrine system
Ectoenzymes are a family of cell surface molecules whose catalytic domain lies in the extracellular region. A subset of this family, nucleotide-metabolizing ectoenzymes, are key components in the regulation of the extracellular balance between nucleotides (e.g., NAD+ or ATP) and nucleosides (e.g., adenosine). Their substrates and products are signalling molecules that act by binding to specific receptors, triggering signals that regulate a variety of functions, ranging from the migration of immune cells, to synaptic transmission in the brain, to hormone/receptor interactions in the glands. Almost two decades of accumulated data indicate that these regulatory processes significantly affect the endocrine system, a tightly controlled information signal complex with clear evidence of fine regulation. Functional models discussed in this review include insulin secretion, bone modelling and the association between hormones and behaviour. The emerging pattern is one of a system operating as a scale-free network that hinges around hubs of key molecules, such as NAD+ or ATP. The underlying natural link between nucleotides, ectoenzymes and the endocrine system is far from being clearly demonstrated. However, the body of evidence supporting the existence of such connection is growing exponentially. This review will try to read the available evidence in a hypothesis-oriented perspective, starting from the description of NAD+ and of ecto- and endoenzymes involved in its metabolism
Accounting for the low survival of the Critically Endangered northern bald ibis Geronticus eremita on a major migratory flyway
AbstractThe poor survival rate of immature northern bald ibises Geronticus eremita during their first years spent outside the natal site is driving the last known wild colony of the migratory eastern population to extinction. To inform emergency conservation action for this Critically Endangered species we investigated the distribution range and behaviour of immature birds in passage and wintering areas, and the threats to which they are subject. We integrated recent satellite telemetry data with visual observations spanning 130 years. We assessed threats across the range, using satellite tracking and field surveys. Our results show that during the years before they return to the natal site in Syria, immature northern bald ibises reside away from the recently identified adult wintering site in the central Ethiopian highlands. They occur mainly across the northernmost 70â80% of the adult migratory range. Historical records suggest that immature birds spend more time along the western Arabian Peninsula now than in the past. This range shift exposes them for longer periods to threats, such as hunting and electrocution on power lines, which are absent from the wintering site used by adult birds. We suggest that other threatened and declining bird species sharing the same flyway probably face the same threats during migration
Recommended from our members
Persistent peri-Heptacene: Synthesis and In Situ Characterization
n-peri-Acenes (n-PAs) have gained interest as model systems of zigzag-edged graphene nanoribbons for potential applications in nanoelectronics and spintronics. However, the synthesis of n-PAs larger than peri-tetracene remains challenging because of their intrinsic open-shell character and high reactivity. Presented here is the synthesis of a hitherto unknown n-PA, that is, peri-heptacene (7-PA), in which the reactive zigzag edges are kinetically protected with eight 4-tBu-C6H4 groups. The formation of 7-PA is validated by high-resolution mass spectrometry and in situ FT-Raman spectroscopy. 7-PA displays a narrow optical energy gap of 1.01 eV and exhibits persistent stability (t1/2â25 min) under inert conditions. Moreover, electron-spin resonance measurements and theoretical studies reveal that 7-PA exhibits an open-shell feature and a significant tetraradical character. This strategy could be considered a modular approach for the construction of next-generation (3 N+1)-PAs (where Nâ„3). © 2021 The Authors. Angewandte Chemie International Edition published by Wiley-VCH Gmb
- âŠ