In the present paper, we review the progress of the project of the classification and construction of invariant differential operators for non-compact, semisimple Lie groups. Our starting point is ...the class of algebras which we called earlier ‘conformal Lie algebras’ (CLA), which have very similar properties to the conformal algebras of Minkowski space-time, though our aim is to go beyond this class in a natural way. For this purpose, we introduced recently the new notion of a parabolic relation between two non-compact, semi-simple Lie algebras G and G′ that have the same complexification and possess maximal parabolic subalgebras with the same complexification.
Supersymmetry Dobrev, Vladimir K
2018, 2018-09-24, Letnik:
49
eBook
With applications in quantum field theory, general relativity and elementary particle physics, this four-volume work studies the invariance of differential operators under Lie algebras, quantum ...groups and superalgebras. This third volume covers supersymmetry, including detailed coverage of conformal supersymmetry in four and some higher dimensions, furthermore quantum superalgebras are also considered. Contents Lie superalgebras Conformal supersymmetry in 4D Examples of conformal supersymmetry for D > 4 Quantum superalgebras
With applications in quantum field theory, general relativity and elementary particle physics, this three-volume work studies the invariance of differential operators under Lie algebras, quantum ...groups and superalgebras. This second volume covers quantum groups in their two main manifestations: quantum algebras and matrix quantum groups. The exposition covers both the general aspects of these and a great variety of concrete explicitly presented examples. The invariant q-difference operators are introduced mainly using representations of quantum algebras on their dual matrix quantum groups as carrier spaces. This is the first book that covers the title matter applied to quantum groups.
With applications in quantum field theory, elementary particle physics and general relativity, this two-volume work studies invariance of differential operators under Lie algebras, quantum groups, ...superalgebras including infinite-dimensional cases, Schrödinger algebras, applications to holography.
This first volume covers the general aspects of Lie algebras and group theory.
Migrant birds face a number of threats throughout their annual cycle, including persecution, collision with energy infrastructure, and habitat and climate change. A key challenge for the conservation ...of migrants is the identification of important habitat, including migratory concentration areas, because species survival rates may be determined by events in geographically very limited areas. Remote‐tracking technology is facilitating the identification of such critical habitat, although the strategic identification of important sites and incorporation of such knowledge in conservation planning remains limited. We tracked 45 individuals of an endangered, soaring migrant (Egyptian vulture Neophron percnopterus), over 75 complete migrations that traversed three continents along the Red Sea Flyway. We summarize and contextualize migration statistics by season and age class, including migration start, midpoint, and end dates, as well as linear and cumulative migration distance, migration duration and speed, and route straightness. Then, using dynamic Brownian bridge movement models, we quantified space use to identify the most important migratory bottlenecks and high‐use areas on the flyway. These areas each accounted for < 5% of the overall movement range of the tracked birds, yet > 20% of all tracks passed through bottlenecks, and > 50% of the overall vulture time spent on migration fell within high‐use areas. The most important sites were located at the southeastern Red Sea coast and Bab‐el‐Mandeb Strait (Saudi Arabia, Yemen, Djibouti), the Suez Canal zone (Egypt), and the Gulf of Iskenderun (Turkey). Discouragingly however, none of the area within the major migratory bottlenecks was protected and < 13% of the high‐use areas were protected. This demonstrates a very concerning gap in the protected area network for migratory soaring birds along the Red Sea Flyway. Because reducing threats at migratory concentrations can be a very efficient approach to protect populations, our work provides clear guidelines where conservation investment is urgently needed to benefit as many as 35 migratory soaring‐bird species that regularly use the Red Sea Flyway.
Quantum Groups Dobrev, Vladimir K
De Gruyter eBooks,
2017, 2017-07-10, Letnik:
39
eBook
Odprti dostop
With applications in quantum field theory, general relativity and elementary particle physics, this two-volume work studies the invariance of differential operators under Lie algebras, quantum groups ...and superalgebras. This second volume covers quantum groups and quantum algebras, supersymmetry and Virasoro algebras.
The Eastern Imperial Eagle (EIE) is a large-sized, globally threatened species with a wide distribution. The species is extremely vulnerable and sensitive to human disturbance and activities in the ...vicinities of its nests. We analyzed the effect of human disturbance in two territories of Eastern Imperial Eagles from Bulgaria in 2008–2009. We recorded 375 cases of different types of human activity in the vicinities of the two surveyed nests – 60 cases in nest A and 315 in nest B. The most common activity around the studied nests was the passing of light motor vehicles (n=100 cases). Our results highlight that the probability of EIE’s reaction is dependent on the type of activity, distance from the nest and the duration of the activity. However, eagles’ reaction is independent from the number of intruders. We found that with the decrease of the distance to the nest, the reaction progresses and is more acute. We found statistical differences between the distance belts and the majority of alert and flight reactions that were recorded at distances up to 300 m from the nests. We reported that humans walking around nests (mainly hunters, fishermen, tourists, people illegally extracting sand in the close vicinities of the nests) result in a large number of reactions of flight off by the eagles thus, leaving the nest unattended. More research on a large scale on this topic is needed including more accurate measures to address human disturbance in EIE territories. The findings will be applied to ensure higher breeding rates and species conservation.
Roosting behaviour during the pre-breeding season is an important part of the Eurasian Griffon Vulture Gyps fulvus life cycle. We demonstrate the importance of roost site selection and its relation ...to the breeding distribution of the Griffon Vulture.
To quantify the distribution, population size, age structure and roosting site selection of the Eurasian Griffon Vulture in the Eastern Rhodopes, Bulgaria during the pre-breeding season.
We used correlation analysis and generalized linear mixed models to examine the relationship between the vultures use of roost sites and their distribution in relation to topographic variables. We additionally used GPS telemetry data from 25 birds to study and compare the use of roosting cliffs.
During the 14-year survey period the number of roosting Eurasian Griffon Vultures gradually increased from 25 birds in 2005 to 201 in 2018. We recorded 16 cliffs used by 124 ± 51 (sd) vultures for roosting. The number of non-adult vultures increased by 25% and reached 41% of all the recorded birds in the last year of the survey. We found that the number of breeding pairs correlated positively with the number of roosting vultures (r
= 0.85) and that roosting cliff selection was determined by cliff length and height, distance to the nearest feeding site, and whether the cliff was used for breeding.
Cliffs regularly used by vultures in the pre-breeding season, were afterwards used for breeding. Thus, cliffs used in the pre-breeding season for roosting could be used as an index for the breeding distribution of the species, and should be protected to sustain the species in and out of the breeding season.
One approach to stabilise small and declining populations is to breed individuals in captivity and release them into the wild to reinforce existing populations while working to reduce threats. ...Population reinforcement programmes require long‐term commitments to be successful and can divert limited resources from other conservation measures. A rigorous evaluation whether reinforcement can stabilise a population is therefore essential to justify investments.
Many migratory species incur high mortality during their first migration, and releasing captive‐bred birds at an older age may therefore benefit reinforcement programmes for migratory birds. We examine whether a small and declining population of a long‐distance migratory raptor—the Egyptian Vulture Neophron percnopterus—can be stabilised using population reinforcement that reduces mortality during the first migration. We used an integrated population model to evaluate realistic reinforcement and survival improvement scenarios to estimate how many captive‐bred birds would need to be released to stabilise the population.
Survival probability of wild juveniles during their first year (0.296; 95% CI 0.234–0.384) was too low for a stable population (population growth rate 0.949; 95% CI 0.940–0.956), but captive‐bred juveniles released in their second calendar year had improved survival (0.566; 95% CI 0.265–0.862) during their first year in the wild.
Reinforcement of 15 birds per year for 30 years was insufficient to achieve a neutral or positive population growth rate. However, reinforcement reduced the probability of extinction by 2049 from 48% without reinforcement to <1% if 12 or more birds were released every year for 30 years. A 6% increase in annual survival probability would likely lead to a stable population without any reinforcement.
Synthesis and applications. Although releasing captive‐bred birds can reduce high juvenile mortality during first migration and assist in postponing local extinction, further improvements of survival in the wild are required to safeguard a migratory population where threats in the wild will persist for decades despite management.
Translated Περίληψη
Μία προσέγγιση που στοχεύει στη σταθεροποίηση μικρών και μειούμενων πληθυσμών είναι η αναπαραγωγή ατόμων σε αιχμαλωσία και στη συνέχεια η απελευθέρωσή τους στην φύση για την ενδυνάμωση των υπαρχόντων πληθυσμών, ενώ παράλληλα συνεχίζονται οι διαχειριστικές δράσεις που στοχεύουν στον περιορισμό των απειλών. Τέτοια προγράμματα ενδυνάμωσης πληθυσμών, για να είναι επιτυχημένα, απαιτούν μακροπρόθεσμη δέσμευση και μπορούν να εκτρέψουν τους ήδη περιορισμένους πόρους από άλλα μέτρα διατήρησης. Είναι επομένως απαραίτητη μια διεξοδική αξιολόγηση του κατά πόσον οι δράσεις ενδυνάμωσης μπορούν να οδηγήσουν έναν πληθυσμό σε σταθεροποίηση, έτσι ώστε πιθανές επενδύσεις σε τέτοιες δράσεις να είναι δικαιολογημένες.
Πολλά μεταναστευτικά είδη πουλιών υφίστανται υψηλή θνησιμότητα κατά το πρώτο τους ταξίδι οπότε η απελευθέρωση ατόμων που έχουν αναπαραχθεί σε αιχμαλωσία αφού έχουν φτάσει σε μεγαλύτερη ηλικία μπορεί να ωφελήσει προγράμματα ενδυνάμωσης που στοχεύουν πληθυσμούς μεταναστευτικών ειδών. Εδώ, εξετάζουμε εάν ένας μικρός και μειούμενος πληθυσμός ενός μεταναστευτικού είδους αρπακτικού ‐ του Ασπροπάρη (Neophron percnopterus) ‐ μπορεί να σταθεροποιηθεί μέσω δράσεων ενίσχυσης που μειώνουν τη θνησιμότητα κατά την πρώτη μετανάστευση. Χρησιμοποιήσαμε πληθυσμιακά μοντέλα για να αξιολογήσουμε ρεαλιστικά σενάρια ενδυνάμωσης και αύξησης της επιβίωσης ώστε να εκτιμήσουμε πόσα άτομα που έχουν αναπαραχθεί σε αιχμαλωσία θα πρέπει να απελευθερωθούν για να επιτευχθεί η σταθεροποίηση του πληθυσμού.
Η πιθανότητα επιβίωσης των άγριων νεαρών ατόμων κατά το πρώτο έτος της ζωής τους (0,296, 95% CI 0,234 – 0,384) ήταν πολύ χαμηλή για να οδηγήσει σε έναν σταθερό πληθυσμό (ρυθμός αύξησης πληθυσμού 0,949, 95% CI 0,940 –0,956), αλλά τα νεαρά άτομα που είχαν αναπαραχθεί σε αιχμαλωσία και απελευθερώθηκαν στον δεύτερο χρόνο της ζωής τους, έδειξαν αυξημένη επιβίωση (0,566, 95% CI 0,265 – 0,886) κατά τη διάρκεια του πρώτου έτους τους στη φύση.
Η ενδυνάμωση του πληθυσμού με την απελευθέρωση 15 πουλιών ετησίως για 30 χρόνια δεν επαρκεί για την επίτευξη είτε σταθερού είτε θετικού ρυθμού αύξησης του πληθυσμού. Ωστόσο, η δράση ενδυνάμωσης μπορεί να μειώσει την πιθανότητα εξαφάνισης από 48% σε λιγότερο από 1% έως το 2049, εάν 12 ή περισσότερα πουλιά απελευθερώνονταν κάθε χρόνο για 30 χρόνια. Επίσης, εάν η ετήσια πιθανότητα επιβίωσης αυξανόταν κατά 8% θα οδηγούσε σε έναν σταθερό πληθυσμό χωρίς να χρειάζεται καμία δράση ενίσχυσης.
Σύνθεση και εφαρμογές. Παρόλο που η ενδυνάμωση του πληθυσμού μπορεί να μειώσει την υψηλή θνησιμότητα των νεαρών ατόμων κατά την πρώτη τους μετανάστευση και να βοηθήσει στην αναστολή μιας τοπικής εξαφάνισης, απαιτείται περαιτέρω βελτίωση της επιβίωσης τους στην φύση για την διασφάλιση ενός μεταναστευτικού πληθυσμού ο οποίος θα συνεχίσει να αντιμετωπίζει απειλές για δεκαετίες παρά τη διαχείριση.
Although releasing captive‐bred birds can reduce high juvenile mortality during first migration and assist in postponing local extinction, further improvements of survival in the wild are required to safeguard a migratory population where threats in the wild will persist for decades despite management.