143 research outputs found
Development of sexual organs and fecundity in Octopus vulgaris Cuvier, 1797 from the Sardinian waters (Mediterranean Sea)
In this paper we report information about the sexual maturity process of 245 Octopus vulgaris specimens (75 females and 170 males) from the Mediterranean Sea. For both sexes, six stages of sexual maturity (immature, developing, maturing, mature, spawning, and spent) are identified on the basis of macroscopic and microscopic observations of the reproductive system and linked with some reproductive indices. A good correspondence between gonad appearance and its histological structure is observed, highlighting, in females, how oviducal gland morphology plays a crucial role in the macroscopic evaluation of maturity. The Gonadosomatic and Hayashi indices, in the two genders, and the Oviducal Gland index in females alone do not allow distinguishing all the stages in an irrefutable way. Data on the potential fecundity, oocyte and spermatophore size are reported and compared with literature. In addition, spermatophore components are also computed. The results reported in this paper lead to easy identification of the different phases of sexual maturation of O. vulgaris and could constitute an important tool for defining assessment models in view of sound management of this species
Balanced metrics on Cartan and Cartan-Hartogs domains
This paper consists of two results dealing with balanced metrics (in S.
Donaldson terminology) on nonconpact complex manifolds. In the first one we
describe all balanced metrics on Cartan domains. In the second one we show that
the only Cartan-Hartogs domain which admits a balanced metric is the complex
hyperbolic space. By combining these results with those obtained in [13]
(Kaehler-Einstein submanifolds of the infinite dimensional projective space, to
appear in Mathematische Annalen) we also provide the first example of complete,
Kaehler-Einstein and projectively induced metric g such that is not
balanced for all .Comment: 11 page
Motivation to donate, job crafting, and organizational citizenship behavior in blood collection volunteers in non-profit organizations
Motivation to donate, job crafting, and organizational citizenship behavior in blood collection volunteers in non-profit organizations
This study assesses the levels of and relationships between the Motivation to donate, Job crafting propensity, and the Organizational citizenship behavior of blood collection volunteers in a non-profit association. An Italian sample of AVIS (the Italian Association of Voluntary Blood donors) blood donors (N = 1215) actively involved in organizing blood collection, were asked to complete the Italian version of the Volunteer Function Index, the Job crafting scale, and the Organizational citizenship behavior scale. The tools were verified by Confirmatory factor analysis and their relationships were explored using Structural equation modeling for hidden variables. The three constructs have overall high scores. Motivation to donate and Job crafting show a clear correlation, with the latter influencing volunteer Organizational citizenship behavior. The study highlights the need to take into consideration the Motivation to donate, Job crafting and Organizational citizenship behavior of volunteers, particularly in countries such as Italy, where blood collection is almost exclusively carried out thanks to spontaneous, altruistic, and disinterested commitment
Reproduction in Heteroteuthis dispar (Rüppell, 1844) (Mollusca: Cephalopoda): a sepiolid reproductive adaptation to an oceanic lifestyle
Small cephalopods of the genus Heteroteuthis are the most pelagic members in the family Sepiolidae. This study examines the reproductive biology of Heteroteuthis dispar (Rüppell, 1844), the first such study on any member of the genus, based on 46 specimens (27 females and 19 males) collected during the Mar-Eco cruise in the North Atlantic in the region of the Mid-Atlantic Ridge in 2004, and compares it with reproductive features in the less pelagic members of the family. The unusually large spermatophores of the males have a very small ejaculatory apparatus and cement body, relative to the size of the sperm mass. Females first mate when they are still maturing: a large sperm mass (up to 3.4% of the female body mass), consisting of one to several spermatangia, was found in an internal seminal receptacle of the majority of the females examined regardless of their maturity state. The seminal receptacle has a unique form and position in this species. The receptacle is a thin-walled sac at the posterior end of the visceral mass that is an outpocketing of, and opens into, the visceropericardial coelom. Spermatangia and sperm from the spermatangia apparently enter into the visceropericardial coelom (which is mostly occupied by the ovary) from the seminal receptacle indicating that ova are fertilised internally, a strategy unknown for decapodiform cephalopods (squid and cuttlefish), but present in most octopods. Fecundity of Heteroteuthis dispar (1,100–1,300 oocytes) is much higher than in other sepiolids whereas the egg size (mean max. length ∼1.6 mm) is the smallest within the family. Spawning is continuous (sensu Rocha et al. in Biol Rev 76:291–304, 2001). These and other reproductive traits are discussed as being adaptations to an oceanic lifestyle
Burnout syndrome in reception systems for illegal immigrants in the Mediterranean. A quantitative and qualitative study of Italian practitioners
Burnout syndrome in reception systems for illegal immigrants in the Mediterranean. A quantitative and qualitative study of Italian practitioners
Illegal immigration throughout the Mediterranean Sea is an intense and epoch-making phenomenon. This quantitative and qualitative study, based on the framework of the JD-R Model of burnout, described and assessed the risk of burnout among practitioners working in the reception system for illegal immigrants. A sample of Italian practitioners completed the Link Burnout Questionnaire (N = 193) and a semistructured interview (N = 108). The analysis of the questionnaires was carried out via ANOVA and χ2 test. The content of the interviews was examined using T-LAB. Quantitative results showed that the sample was generally at risk of burnout, and about a quarter were at severe risk. Qualitative results highlighted aspects of burnout that are specific to this working context: large workload, mental fatigue, and lack of social support; inability to understand the language and cultural differences of the immigrants; having to deal with organisational problems that come up repeatedly. This study offers coping strategies that can improve organisational health and performance of practitioners working in illegal immigration. Italy's shape, geographical location, and geo-political role make it a case in point for the whole European continent regarding the sustainability of illegal immigration across the Mediterranean Sea
Health-related quality of life in patients with primary open-angle glaucoma. An italian multicentre observational study
PurposeAs a progressive condition, glaucoma may impair health-related quality of life (HRQoL), due to vision loss and other factors. This study evaluated HRQoL in a cohort of patients treated for primary open-angle glaucoma (POAG) and assessed its association with clinical features.
MethodsThis was an Italian, multicentre, cross-sectional, observational study with the subgroup of newly diagnosed patients with POAG prospectively followed up for one year. Patients with previous or new diagnosis (or strong clinical suspicion) of POAG aged >18years were considered eligible. Information was collected on demographic characteristics, medical history, clinical presentation and POAG treatments. HRQoL was measured using the 25-item National Eye Institute Visual Function Questionnaire (NEI-VFQ-25) and Glaucoma Symptom Scale (GSS). Subscale and total scores were obtained and a Pearson correlation coefficient between instruments' scores calculated.
ResultsA total of 3227 patients were enrolled from 2012 to 2013 and 3169 were analysed. Mean age was 66.9years. A total of 93.8% had a previous diagnosis (median duration: 8.0years). Median values for mean deviation and pattern standard deviation were 3.9 and 3.6 dB, respectively. Mean scores on most subscales of the NEI-VFQ-25 exceeded 75.0 and mean GSS subscale scores ranged between 70.8 and 79.7 (with a total mean score of 74.8). HRQoL scores on both scales were significantly inversely associated with POAG severity.
ConclusionIn this large sample of Italians treated for POAG, disease severity was limited and HRQoL scores were high. QoL decreased with advancing disease severity. These findings confirm the role of vision loss in impairing QoL in POAG, underlying the importance of timely detection and appropriate treatment
Analysis of Score-Level Fusion Rules for Deepfake Detection
Deepfake detection is of fundamental importance to preserve the reliability of multimedia communications. Modern deepfake detection systems are often specialized on one or more types of manipulation but are not able to generalize. On the other hand, when properly designed, ensemble learning and fusion techniques can reduce this issue. In this paper, we exploit the complementarity of different individual classifiers and evaluate which fusion rules are best suited to increase the generalization capacity of modern deepfake detection systems. We also give some insights to designers for selecting the most appropriate approach
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