Bayesian estimate of Australian humpback whale calving interval under sparse resighting rates: 1987–2009

This study estimates a calving interval for humpback whales from a longterm photo-ID catalogue of 2,973 individuals resighted in Hervey Bay, East Australia. The study proposes a modification of two existing methods to handle partial identification of sex and age-classes of whales from visual surveys. One method truncates the data to just breeding females and discards all resighting events prior to the first observed breeding event. The second method utilises the multi-stage mark recapture (MSMR) framework and multi-event extension to include all resighted individuals and their entire encounter history. The performance of each method is assessed and the conditioning required to handle ambiguity of sex and age-classes is detailed, which is subtly different from most other mark-recapture methods. Both truncation and the multi-event methods led to similar estimates of calving intervals: 2.98 years (95% CI: 2.27–3.51) and 2.78 years (95% CI: 2.23–3.68) respectively. More importantly, estimates were more sensitive to the exact specification of resighting probabilities among age and sex classes than to the type of conditioning. However, the multi-event framework resulted in more precise estimates of other important life-history parameters such as apparent survival, and included a wider constituency of age and sex classes

Device and method for converting direct current into alternate current

The device for converting direct current into alternate current comprises a multilevel converter associated with at least a source of direct current and a modulation unit having piloting means for piloting the converter for the conversion of the direct current into an alternate output current, in which the modulation unit comprises comparison means for comparing the output current value with a preset positive threshold value and a preset negative threshold value, the piloting means being suitable for piloting the converter with a pulse modulation of the unipolar type in the event of the output current value being above the positive threshold value or below the negative threshold value and with a pulse modulation of the complementary type in the event of the output current value being below the positive threshold value and above the negative threshold value. The method for converting direct current into alternate current comprises a piloting phase of a multilevel converter for the conversion of a direct voltage into an alternate output voltage, a comparison phase of the output current value with a preset positive threshold value and a preset negative threshold value, the piloting phase being suitable for piloting the converter with a pulse modulation of the unipolar type in the event of the output current value being above the positive threshold value or below the negative threshold value and with a pulse modulation of the complementary type in the event of the output current value being below the positive threshold value and above the negative threshold value

Meccanismi di addolcimento ed incrudimento dovuti allo sviluppo di raft in una superlega monocristallina a base di nichel

Le curve di creep di superleghe a base nichel monocristalline rinforzate dalla precipitazione della fase ?’sono spesso dominate dallo stadio accelerante/terziario dovuto all’accumulazione di un danno interno nondirettamente relazionato a meccanismi di frattura, ma piuttosto a una variazione della densità e/o mobilitàdelle dislocazioni mobili che può essere correlata con la deformazione da creep accumulata.Un’attenta esamina dello stadio accelerante ottenuto sulla superlega SMP14 mostra differenti regimi diaccumulazione della deformazione in funzione dalla sollecitazione e temperatura applicate. Talecomportamento sperimentale può essere razionalizzato dall’evoluzione, durante il creep, della morfologiadella fase rinforzante ?’

Analisi del comportamento a creep della superlega Nimonic 263

Il comportamento a creep della superlega Nimonic 263 è stato studiato a carico e temperatura costantenell’intervallo 750-30MPa/600-950°C. I risultati sperimentali hanno mostrato che la forma della curva dicreep dipende fortemente dalle sollecitazioni applicate. Nelle prove eseguite a sollecitazioni superiori al caricodi snervamento, le curve di creep consistono essenzialmente nel solo stadio primario/decelerante, mentre persollecitazioni inferiori, ed in particolare ai più bassi carichi ed elevate temperature qui studiati, lo stadioprimario diventa molto piccolo e breve, ed altri stadi di deformazione dominano le curve di creep.In questo lavoro si dimostra che un’unica e semplice equazione costitutiva, basata sulla moltiplicazione eannichilazione delle dislocazioni mobili, è in grado di descrivere e interpolare correttamente le curve di creepin tutto l’intervallo di sollecitazioni/temperature esplorat

Microstructure evolution and creep behaviour of a new intermetallic alloy

The preliminary results of microstructural characterization and creep behaviour of an innovative TiAl 8% atomic Nb alloy are exposed in this paper. Two different batches of this material, with same nominal chemical composition, but produced through different solidification processes and heat treatments, have been studied. The production processes generated different ? + ?2 microstructures in the two batches, both analyzed through X ray diffractometry (XRD) and transmission electron microscopy (TEM). Constant load creep tests have been performed on both batches at the same temperatures (700?C and 850?C) and loads in order to compare the creep behaviours. XRD and TEM analyses have been carried out after creep tests in order to determine microstructural evolution of the materials and to establish correlation with creep behaviours

Analisi microchimica mediante SPEM di una superlega di Nichel dopo prove di creep

Lo scopo di questo lavoro è mostrare le potenzialità delle analisi micro-chimiche di superficie, in particolare laspettroscopia Scanning PhotoEmission Microscopy (SPEM) ad alta risoluzione, nello studio dei fenomeni diffusiviche hanno luogo fra le fasi g e g’ nelle superleghe di Ni a seguito del creep. Si riportano le analisi condotte su unasuperlega monocristallina, CM186LC, prima e dopo prove di creep alle temperature di 800 e 900 °C.Le misure di fotoemissione ai raggi X (XPS) ad elevata risoluzione spaziale sono state effettuate presso labeam-line ESCA-microscopy del sincrotrone Elettra di Trieste, in cui è stato utilizzato lo SPEM, che opera inmodalità sia di immagine che di spettroscopia puntuale, producendo una microsonda a raggi X di diametroinferiore a 50 nm. L’alta risoluzione permette di esaminare separatamente la composizione chimica della faserinforzante g’ e della matrice g caratterizzanti la superlega. In questo modo è possibile studiare la partizionedegli elementi di lega tra le fasi nel materiale vergine e la sua evoluzione dopo le prove di creep

Chemical composition and antimicrobial activity of essential oils from Cuminum cyminum L. collected in different areas of Morocco

Essential oils from 8 Cuminum cyminum local populations collected in Morocco were investigated for their chemical composition and antimicrobial activity. The chemical composition, investigated by gas chromatographic technique, revealed a common fingerprint in all Moroccan samples: twenty-five compounds were identified with γ-terpinen-7-al being the major component in all samples studied. The antimicrobial activity of cumin essential oils were tested against 10 bacterial strains, belonging to 8 different species, and 6 yeast strains, belonging to 4 species. Lactic acid bacteria showed a good resistance to all essential oil tested while overall the cumin essential oils showed a strong antifungal activity that affected both maximum specific growth rate and lag tim

Factors driving patterns and trends in strandings of small cetaceans

The incidence of cetacean strandings is expected to depend on a combination of factors, including the dis- tribution and abundance of the cetaceans, their prey, and causes of mortality (e.g. natural, fishery bycatch), as well as currents and winds which affect whether carcasses reach the shore. We investigated spatiotemporal patterns and trends in the numbers of strandings of three species of small cetacean in Galicia (NW Spain) and their relationships with meteoro- logical, oceanographic, prey abundance and fishing-related variables, aiming to disentangle the relationship that may exist between these factors, cetacean abundance and mor- tality off the coast. Strandings of 1166 common dolphins (Delphinus delphis), 118 bottlenose dolphins (Tursiops truncatus) and 90 harbour porpoises (Phocoena phocoena) during 2000–2013 were analysed. Generalised additive and generalised additive-mixed model results showed that the variables which best explained the pattern of strandings of the three cetacean species were those related with local ocean meteorology (strength and direction of the North– South component of the winds and the number of days with South-West winds) and the winter North Atlantic Oscil- lation Index. There were no significant relationships with indices of fishing effort or landings. Only bottlenose dolphin showed possible fluctuations in local abundance over the study period. There was no evidence of long-term trends in number of strandings in any of the species and their abun- dances were, therefore, considered to have been relatively stable during the study period.Versión del editor2,01

Skin Lesions on Common Bottlenose Dolphins (Tursiops truncatus) from Three Sites in the Northwest Atlantic, USA

Skin disease occurs frequently in many cetacean species across the globe; methods to categorize lesions have relied on photo-identification (photo-id), stranding, and by-catch data. The current study used photo-id data from four sampling months during 2009 to estimate skin lesion prevalence and type occurring on bottlenose dolphins (Tursiops truncatus) from three sites along the southeast United States coast [Sarasota Bay, FL (SSB); near Brunswick and Sapelo Island, GA (BSG); and near Charleston, SC (CHS)]. The prevalence of lesions was highest among BSG dolphins (P = 0.587) and lowest in SSB (P = 0.380), and the overall prevalence was significantly different among all sites (p<0.0167). Logistic regression modeling revealed a significant reduction in the odds of lesion occurrence for increasing water temperatures (OR = 0.92; 95%CI:0.906–0.938) and a significantly increased odds of lesion occurrence for BSG dolphins (OR = 1.39; 95%CI:1.203–1.614). Approximately one-third of the lesioned dolphins from each site presented with multiple types, and population differences in lesion type occurrence were observed (p<0.05). Lesions on stranded dolphins were sampled to determine the etiology of different lesion types, which included three visually distinct samples positive for herpesvirus. Although generally considered non-fatal, skin disease may be indicative of animal health or exposure to anthropogenic or environmental threats, and photo-id data provide an efficient and cost-effective approach to document the occurrence of skin lesions in free-ranging populations